Thesis (MScMedSc (Medical Imaging and Clinical Oncology. Nuclear Medicine))--University of Stellenbosch, 2010. / Thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Nuclear Medicine at Stellenbosch University. / ENGLISH ABSTRACT: Introduction: There is conflicting data on the value of single photon emission tomography (SPECT) for the diagnosis of neuropsychiatric SLE (NPSLE). Visual assessment of brain SPECT scans is the standard approach in clinical practice. However the definition and identification of significant changes may be limited by a high interobserver variability, especially in centres with limited experience. This may be reduced by a more objective semi-quantitative assessment. The objectives of this study were to determine the sensitivity and specificity of SPECT for the detection of NPSLE at our institution using visual assesment, to determine the additional value of using an objective semi-quantitative diagnostic criterion, and to investigate the correlation between abnormal perfusion pattern and clinical NPSLE classification in patients with active NPSLE. Material and methods: Nineteen patients with NPSLE and 19 normal controls were studied with brain SPECT. Scans were interpreted blindly by two nuclear medicine physicians using two methods; visual and semi-quantitative assessments. In the visual method, overall visual impression was recorded for each scan using a four point scale, where A=normal, B=probably normal, C=probably abnormal, and D=abnormal. In addition, each brain region was assigned a severity score from 0=normal perfusion to 3=severe hypoperfusion. In the semi-quantitative assessment, ten-band color scale was used, and perfusion deficit was quantified on the side with the lower color intensity comparing to the contralateral side. A score was given to the region with perfusion deficit according to the difference (in color bands) between the two hemispheres. Analysis was performed for the visual assessment method (overall impression and severity scores) and the semi-quantitative assessment method using a receiver operator characteristic (ROC) curve. Optimal cut-off points were determined and the accuracy of the different techniques was also compared statistically. Finally, the correlation was determined between the SPECT perfusion pattern and the clinical pattern of disease. Results: An ROC curve analysis for the overall visual impression resulted in an area under the curve of 0.76. At a cut-off point of C (probably abnormal), brain SPECT had 89% sensitivity and 57% specificity for the diagnosis of NPSLE. The severity score which include the total severity score and the modified total severity score resulted in areas under the curve of 0.75 and 0.79 respectively. The semi-quantitative assessment resulted in areas under the ROC curve of 0.80. Statistically, there was no difference between the overall visual impression, visual severity scores, and the semi-quantitative assessment. Agreement analysis between the SPECT pattern and clinical pattern of disease showed agreement in 91.6% in the diffuse pattern, whereas agreement in the focal pattern was seen in only 42.8%. Discussion and Conclusion: In this study, we found that brain SPECT is able to diagnose active NPSLE with a high sensitivity and moderate specificity. The overall visual impression, visual severity scores, and the semi-quantitative assessment showed no significant differences between the techniques. The use of the semi-quantitative assessment described may be useful in centers with limited experience in the interpretation of brain SPECT. The correlation between the SPECT pattern and clinical disease pattern may provide some insights into the pathophysiology of NPSLE. / AFRIKAANSE OPSOMMING: Inleiding: Daar is teenstrydige inligting oor die waarde van brein enkelfoton emissie tomografie (EFET) vir die diagnose van neuropsigiatriese SLE (NPSLE). Visuele beoordeling van brein EFET flikkergramme is die standaard benadering in kliniese praktyk. Die definisie en identifisering van betekenisvolle veranderinge mag egter beperk word deur 'n hoë inte-waarnemer wisseling, veral in sentra met beperkte ondervinding. Dit mag verminder word deur 'n meer objektiewe semi-kwantitatiewe beoordeling. Die doel van hierdie studie was om 1. Die sensitiwiteit en spesifisiteit van EFET vir die opspoor van NPSLE in ons instelling te bepaal, 2. Die bykomende waarde van 'n objektiewe semi-kwantitatiewe diagnostiese kriterium vas te stel, en 3. Die korrelasie tussen 'n abnormale perfusiepatroon en 'n kliniese NPSLE klassifikasie in pasiënte met aktiewe NPSLE te ondersoek. Materiaal en Metodes: Negentien pasiënte met NPSLE en 19 normale kontroles is met brein EFET bestudeer. Flikkergramme is blind deur twee kerngeneeskundiges geïnterpreteer, deur gebruik te maak van twee metodes, 'n visuele en semi-kwantitatiewe beoordeling. Vir elke flikkergram is 'n globale visuele indruk genoteer deur gebruik te maak van 'n 4-punt skaal, waar A=normaal, B=waarskynlik normaal, C= waarskynlik abnormaal, en D=abnormaal. Bykomend is 'n ernstigheidsgraad waarde van 0=normale perfusie tot 3=erge hipoperfusie vir elke breinstreek toegeken. Vir die semi-kwantitatiewe beoordeling is 'n telling vir streke met laer intensiteit vergeleke met die kontralaterale kant toegeken, volgens die verskille in kleurbande deur gebruik te maak van 'n tienbandskaal. Die visuele metodes vir die globale indruk, visuele ernstigheidsgraad waarde, en die semi-kwantitatiewe beoordeling is geanaliseer deur 'n relatiewe funksioneringskenmerk (receiver operator characteristic (ROC)) kurwe te gebruik en optimale afsnypunte te bepaal. Die akkuraatheid van die verskillende tegnieke is ook statisties vergelyk. Laastens is die korrelasie tussen die EFET perfusiepatroon en die kliniese siektepatroon bepaal. Resultate: 'n ROC kurwe analise vir die globale visuele indruk het gelei tot 'n area onder die kurwe van 0.77. By 'n afsnypunt van (C) het brein EFET 'n sensitiwiteit van 89% en 'n spesifisiteit van 57% vir die diagnose van NPSLE gehad. Die visuele ernstigheidsgraad telling, en die semi-kwantitatiewe beoordeling het onderskeidelik tot areas onder die ROC kurwe van 0.75 en 0.79 vir die visuele ernstigheidsgraad waarde, en 0.8 vir die semi-kwantitatiewe beoordeling gelei. Statisties was daar geen verskil tussen die globale visuele indruk, die visuele ernstigheidsgraad waarde, en die semi-kwantitatiewe beoordeling nie. Ooreenstemmingsanalise tussen die EFET patroon en kliniese siektepatrone het 'n ooreenstemming van 91.6% in die diffuse patroon getoon, terwyl die fokale patroon ooreenstemming van slegs 42.8% getoon het. Bespreking en Gevolgtrekkig: In hierdie studie is gevind dat brein EFET 'n diagnose van NPSLE kan maak met 'n hoë sensitiwiteit en gemiddelde spesifisiteit. Die globale visuele indruk, visuele ernstigheidsgraad waarde, en die semi-kwantitatiewe beoordeling wat beskryf is, het geen betekenisvolle verskille tussen die tegnieke getoon nie. Die gebruik van die semi-kwantitatiewe beoordeling wat beskryf is, mag van waarde wees in sentra met beperkte ondervinding in the interpretasie van brein EFET. Die korrelasie tussen die EFET patroon en kliniese siektepatrone mag insig gee in die patofisiologie van NPSLE.

Thesis (MScMedSc (Medical Imaging and Clinical Oncology. Nuclear Medicine))--University of Stellenbosch, 2007. / Introduction: Whole body bone scintigraphy with Tc-99m MDP is able to provide a survey of the entire skeleton. The question arises if it is mandatory to perform a whole body bone scan in all patients, irrespective of the clinical indication. The aim of this study is to determine the implications of performing limited imaging in patients who had whole body bone scan for various clinical patholgy with Tc-99m MDP, in order to determine if limited imaging would be acceptable in selected pathologies. This may enable gamma camera time to be optimally utilized in units with limited facilities. Materials and Methods: Reports of 3015 patients with various clinical pathologies who had whole body bone scans with Tc-99m MDP in our department from January 2002 to December 2004 were retrospectively reviewed. The presence of pathologic radiotracer uptake was analyzed in order to establish the pattern of distribution. Clinically significant skeletal lesions were classified according to the anatomical regions where they were located viz; skull (including the neck), axial skeleton (including the pelvis and shoulders) and limbs. Results: Our results showed that in patients with lung cancer, soft tissue sarcoma, and myeloma, there was an error in more than 25% of patients when limited imaging was performed. In patients with cancer of the breast, prostate, kidney, gastrointestinal system, and reproductive system and lymphoma there is an error in less than 5% of patients when limited imaging is employed. For iv patients with more localized musculoskeletal disorders such as suspected stress fractures, complicated joint prosthesis and avascular necrosis of the femur head, regional imaging of the area of pathology showed a percentage error of less than 6%.

Thesis (MSc (Medical Imaging and Clinical Oncology. Nuclear Medicine))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: Radioiodine therapy is reputed to yield poorer results in male patients than in females. We retrospectively reviewed the records of 308 patients treated with radioiodine-131 (RAI) for Graves’ disease (n=266, 86.4%), toxic multinodular goitres (n=35, 11.4%) and toxic solitary nodules (n=7, 2.3%). The mean age of the men was 44 ±13.6 years (range 14-77 years). Patients with GD were predominantly in the younger age groups, while those with toxic nodular goitres were in the older range. Two hundred and fifty-nine patients (84.1%) were treated with a single dose of RAI, while 49 (15.9%) required further doses. A second dose had to be administered to 38 patients, while 8 received 3 doses, 2 got 4 doses and 1 patient had 5 doses in all (these included a first dose received prior to referral to our Thyroid Clinic). Cure was determined as euthyroidism or hypothyroidism at the 3-month follow-up visit. The average pre-treatment T4 value was 68.9 ± 31.8 pmol/L (range 5.7 – 155 pmol/L); while the mean Tc-99m pertechnetate uptake value was 15.8 ± 10.9% (range 0.88 - 62.9). Patients with GD presented with more severe hyperthyroidism than the other patients; mean free T4 of 71.9 ± 31.1 pmol/L compared to 51.4 ± 29.9 pmol/L for the TMG group of patients, and 39.6 ± 26.8 pmol/L for the TSN group (ANOVA p<0.0001, confirmed by the Kruskal-Wallis test). Patients with TMG and TSN were treated with higher doses than patients with GD; mean first doses of 349.3 ± 88.5 MBq and 428.1 ± 28.6 MBq respectively, compared to a mean dose of 325.1 ± 69.3 MBq for patients with GD. Treatment with multiple doses of RAI correlated with higher values of T4 and T3 at presentation (p<0.0001). However, none of the baseline variables of age, T4 and T3, and first dose of RAI was significant predictors of free T4 outcome at 3 months. A consistently higher dose was administered to the male patients, compared to female patients of similar age, diagnosis and level of thyrotoxicosis (Tc-99m pertechnetate uptake). Despite this, male patients had similar outcomes as the female patients 3 months after therapy. Our findings lend weight to the theory that male patients are more difficult to treat than their female counterparts, seeing that the former had similar outcomes despite the significantly higher doses of RAI administered to the males. / AFRIKAANSE OPSOMMING: Radiojodium terapie lewer na bewering swakker resultate in mans as in vroulike pasiënte. Die inligting van 308 pasiënte met Grave se siekte (n=266, 86.4%), toksiese multinodulêre tiroïed (n=35, 11.4%) en enkel toksiese nodules (n=7, 2.3%) wat met radiojodium (I-131) behandel is, is retrospektief nagegaan. Die gemiddelde ouderdom van die mans was 44 ±13.6 jaar (reikwydte 14-77 jaar). Die meeste pasiënte met Grave se siekte was in die jonger ouderdomsgroep, terwyl dié met toksiese multinodulêre tiroïed, ouer was. Tweehonderd nege-en-vyftig pasiënte (84.1%) is met ‘n enkel dosis radiojodium behandel, terwyl 49 (15.9%) meer as een dosis benodig het. ‘n Tweede dosis is aan 38 pasiënte gegee, terwyl agt 3 dosisse, twee 4 dosisse en 1 pasiënt 5 dosisse in totaal ontvang het (wat ‘n eerste dosis voor verwysing na die tiroïedkliniek, ingesluit het). Herstel is gedefinieer as eutiroïdisme of hipotiroidisme tydens die drie maande opvolgbesoek. Die gemiddelde T4-waarde voor behandeling was 68.9 ± 31.8 pmol/L (reikwydte 5.7–155 pmol/L); terwyl die gemiddelde Tc-99m pertegnetaatopname 15.8 ± 10.9% (reikwydte 0.88–62.9) was. Pasiënte met Grave se siekte het met erger hipertiroidisme as die ander pasiënte gepresenteer; met ‘n gemiddelde vry T4 van 71.9 ± 31.1 pmol/L vergeleke met 51.4 ± 29.9 pmol/L vir die toksiese multinodulêre tiroïedgroep en 39.6 ± 26.8 pmol/L vir die enkel toksiese nodule groep (ANOVA p<0.0001, bevestig met die Kruskal-Wallistoets). Pasiënte met toksiese multinodulêre tiroïed en enkel toksiese nodule, is met hoër dosisse as dié met Grave se siekte behandel; met ‘n gemiddelde eerste dosis van 349.3 ± 88.5 MBq en 428.1 ± 28.6 MBq onderskeidelik, vergeleke met ‘n gemiddelde dosis van 325.1 ± 69.3 MBq vir pasiënte met Grave se siekte. Behandeling met meer as een dosis radiojodium het gekorreleer met hoër T4- en T3- waardes by (p<0.0001). Geen van die basislyn veranderlikes (ouderdom, T4 en T3, en die eerste dosis radiojodium) was egter ‘n betekenisvolle voorspeller van die vry T4 uitkoms op 3 maande nie. Die dosis wat aan manlike pasiënte toegedien is, was konstant hoër, vergeleke met die vroulike pasiënte van dieselfde ouderdom, diagnose en vlak van tirotoksikose. (Tc-99m pertegnetaatopname). Ongeag hiervan, was die uitkoms by manlike en vroulike pasiënte 3 maande na terapie dieselfde. Ons bevindinge dra by tot die teorie dat manlike pasiënte moeiliker is om te behandel as hul vroulike eweknieë, aangesien mans soortgelyke uitkomste gehad het ten spyte van betekenisvol hoër dosisse radiojodium.

Thesis (MScMedSC (Medical Imaging and Clinical Oncology. Nuclear Medicine))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Single photon emission computed tomography (SPECT) with a superior contrast resolution has been shown to be more sensitive and specific with a lower nondiagnostic rate than planar imaging in many nuclear medicine studies but it is still not being routinely implemented in V/Q studies at many centres including Tygerberg Hospital. There are many studies on V/Q SPECT using Technegas as a ventilation agent but very limited studies available on 81m Kr gas. Aim: To clinically compare conventional planar and SPECT V/Q imaging using 81mKr gas in the diagnosis of pulmonary embolism, with CTPA as the gold standard. Patients and Methods: All patients referred with clinical suspicion of pulmonary embolism were assessed. The inclusion criteria were normal chest radiograph, normal renal function and no contrast allergy. Exclusion criteria were age below 18 years old, pregnancy, abnormal chest radiograph, abnormal serum creatinine/urea levels and unstable patients. A Well’s score was assigned to each enrolled patient. Perfusion scintigraphy was performed after intravenous injection 125 MBq of 99mTc MAA. Ventilation scintigraphy was performed with 81mKr gas. On a dual head camera, SPECT was done before planar acquisition, while perfusion was done before ventilation imaging in the same position. Planar V/Q images consisted of 6 standard views. All V/Q SPECT images were reconstructed using ordered-subset expectation-maximization (OSEM) algorithm and a post-reconstruction 3D Butterworth filters were applied. V/Q Planar and V/Q SPECT images were later evaluated and reviewed separately and reported based on recent EANM guidelines blinded to the CTPA results. All patients underwent multi-slice CTPA examinations on a 40-detector row scanner. The images were later assessed and reported blinded to the V/Q results. Statistical analysis was done using the Fisher exact test for comparison of categorical variables and the one-way ANOVA for continuous variables (p<0.05 was significant). Results: A total of 104 consecutive patients were referred with clinical suspicion of pulmonary embolism. Seventy-nine patients were excluded from this study mostly due to abnormal serum creatinine/urea levels. Only 25 patients were included in this study, with a mean age of 48 ± 19 years, and 64% being females. When compared to CTPA as gold standard, the prevalence of PE was 16% [5% – 37% at 95% CI], sensitivity 75% [21% – 99% at 95% CI], specificity 90% [68% – 98% at 95% CI], positive predictive value 60% [17% – 93% at 95% CI], negative predictive value 95% [73% – 100% at 95% CI] and diagnostic accuracy 88% [69% – 97%at 95% CI] for both V/Q Planar and SPECT. V/Q Planar showed a lower reader confidence i.e. could only clearly resolve 72% of cases compared to V/Q SPECT, which could precisely interpret all cases, showed more and better delineated mismatch vs match and segmental vs non-segmental defects. All patients who were scored as PE unlikely on Wells’ score (4) had PE ruled out on CTPA (p=0.04581) as well as 89% of patients on V/Q SPECT and V/Q Planar. Conclusion: Based on this study, V/Q Planar and V/Q SPECT have a similar diagnostic performance in patients with a normal or near normal chest X-rays. / AFRIKAANSE OPSOMMING: Enkelfoton emissie rekenaartomografie (EFERT) met beter kontrasresolusie is bewys om meer sensitief en spesifiek met ‘n laer nie-diagnostiese opbrengs as planare beelding in verskeie kerngeneeskunde ondersoeke te wees. In Tygerberg Hospitaal, soos in verskeie ander sentra, word dit egter steeds nie roetineweg vir ventilasie-perfusiestudies (V/Q) geïmplementeer nie. Daar is verskeie EFERT V/Q studies met Technegas as ventilasie agens, maar beperkte studies met 81m Kr gas beskikbaar. Doel: Om konvensionele planare en EFERT V/Q beelding vir die diagnose van pulmonale embolisme met mekaar te vergelyk, met rekenaartomografie pulmonale angiografie (RTPA) as goue standaard. Pasiënte en Metodes: Alle pasiënte wat met ‘n kliniese vermoede van pulmonale embolisme verwys is, is geevalueer. Die insluitingskriteria was ’n normale borskas Xstraal, normale nierfunksie en geen kontrasallergie nie. Uitsluitingskriteria was pasiënte jonger as 18 jaar, swanger pasiënte, abnormale borskas X-straal, abnormale serum kreatinien / ureumvlakke en onstabiele pasiënte. ’n Wells telling is vir elke pasiënt wat in die studie ingesluit is, bepaal. Perfusiebeelding is uitgevoer na die intraveneuse toediening van 125 MBq 99mTc MAA. Ventilasiestudies is gedoen met 81mKr gas. Die V/Q EFERT studies is voor die planare beelding met ’n dubbelkop gammakamera uitgevoer. Perfusiebeelding is voor die ventilasie in dieselfde posisie verkry. V/Q planare beelding het bestaan uit 6 standaard beelde. Alle V/Q EFERT is met “ordered-subset expectationmaximization” (OSEM) algoritmes verwerk, en post-rekonstruksie 3D Butterworth filters is toegepas. V/Q planare en V/Q EFERT beelding is later afsonderlik en sonder RTPA inligting volgens onlangse EANM riglyne evalueer en gerapporteer. ‘n Veelsnit RTPA met ‘n 40 snit skandeerder is op alle pasiënte uitgevoer. Die beelde is later beoordeel en gerapporteer sonder inagneming van die V/Q beeldingsresultate Statistiese verwerking is gedoen met die Fisher presisietoets vir vergelyking van kategoriese veranderlikes en die eenrigting ANOVA vir kontinue veranderlikes (p<0.05 is statisties betekenisvol). Resultate: ‘n Totaal van 104 opeenvolgende pasiënte met ‘n kliniese vermoede van pulmonale embolisme is verwys. Nege-en-sewentig pasiënte is uitgesluit, in die meeste gevalle as gevolg van abnormale serum kreatinienvlakke. Slegs 25 pasiënte is ingesluit, met ’n gemiddelde ouderdom van 48 ± 19 jaar, en 64% vroue. In vergelyking met RTPA as goudstandaard, was die prevalensie van PE 16% [5% – 37% met 95% VI], sensitiwiteit 75% [21% – 99% met 95% VI], spesifisiteit 90% [68% – 98% met 95% VI], positiewe voorspellingswaarde 60% [17% – 93% met 95% VI], negatiewe voorspellingswaarde 95% [73% – 100% met 95% VI] en diagnostiese akkuraatheid van 88% [69% – 97% met 95% VI] vir beide planare en EFERT V/Q beelde. V/Q planare beelde het ‘n laer lesersvertroue getoon, nl. dat slegs 72% van gevalle opgelos kon word relatief tot V/Q EFERT beelde, wat in alle gevalle presies geïnterpreteer kon word, met meer en beter omskrewe nie-ooreenstemmende teenoor ooreenstemmende en segmentele teenoor nie-segmentele defekte. In alle pasiënte met ‘n Wells puntetelling van 4 is PE met die RTPA uitgeskakel (p=0.04581), terwyl dit in 89% van pasiënte met V/Q EFERT en planare beelde uitgeskakel is. Gevolgtrekking: Gebaseer op hierdie studie het V/Q planare en EFERT beelding ‘n ooreenstemmende diagnostiese prestasie in pasiënte met ’n normale of naby normale borskas X-straal.

Thesis (MSc)--Stellenbosch University, 2005. / ENGLISH ABSTRACT: Introduction: Quality assurance in Nuclear Medicine is of utmost importance in order to ensure optimal scintigraphic results and correct patient management. A customised Quality Management System (QMS) should be documented and implemented by following the international guidelines set by the International Standardisation Organization (ISO). Materials & Methods: A Quality Control Manual (QCM), defining the departmental quality policy, mission, vision and objectives was customised following the framework of a tried and tested design. As ISO focuses on client satisfaction and staff harmony, the following departmental objectives were audited in working towards the accreditation of the Nuclear Medicine Department of Tygerberg Hospital: referring physician satisfaction, patient satisfaction as well as staff satisfaction and harmony. Information was collected by means of questionnaires completed by referring physicians and staff members. One-on-one interviews were executed on patients. An international ISO accredited Nuclear Medicine department was visited to establish the suggested path to follow en route to successful ISO accreditation and certification. Results: Referring physicians indicated overall satisfaction with service provision, but a need for electronic report and image transfers seemed too dominant. The patient satisfaction survey resulted into overall satisfaction with personal service providing, but the provision of written and understandable information, long waiting times and t equipment must receive attention. Staff questionnaires indicated a general lack of communication between different professional groups and the need for interpersonal loyalty and team building. Improvement measures were identified to ensure the continuous improvement of the QMS by focusing on these quality parameters. Conclusion: The department has QA procedures in place, but does not meet all criteria for external accreditation. In order to ensure departmental harmony and sustainability of client and staff satisfaction, the departmental objectives in measured and improved where needed. The successful implementation and continuous improvement of a customised QMS, following the guidelines outlined in the QCM will lead to successful accreditation. / AFRIKAANSE OPSOMMING: Inleiding: Die belangrikheid van kwaliteit versekering in Kerngeneeskunde vir die versekering van optimale flikkergrafiese resultate en korrekte pasient handtering kan nie onderskat word me. 'n Klantgerigte Kwaliteitsbeheersisteem (KBS) moet gedokumenteer en geimplimenteer word vir die Kerngeneeskunde Departement deur die riglyne te volg soos uiteengesit deur die Internationale Standardiserings Organisasie (ISO). Materiale & Metodes: 'n Kwaliteitskontrol handleiding (KB), wat die departementele kwaliteitsbeleid, die missie en visie asook die departementele doelwitte definieer is ontwerp en saamgestel vir die Kerngeneeskunde departement van Tygerberg Hospitaal. Hierdie ontwerp is gebaseer op die raamwerk van 'n aanvaarde kwalteitsbeheersisteem. ISO fokus op klante tevredenheid asook personeel harmonie en tevredenheid. Vir hierdie rede is daar 'n tevredenheidpeiling uitgevoer op die klante en personeel in die strewe na ISO akkreditasie en sertifikasie. Inligting was versamel deur vraelyste wat ingevul was deur die verwysende geneeshere, pasiente en personeel. Resultate: 'n Kwaliteitskontrole handleiding was saamgestel VIr gebruik in die Kerngeneeskunde department. Die interne audit resultate het aangedui dat die verwysende geneeshere tevrede is met die algehele dienslewering. Die behoefde aan elektronies versende verlae en beelde was dominerend. Die pasient tevredenheidspeiling het bevestig dat die pasiente tevrede is met persoonlike dienslewering, maar 'n tekort aan verstaanbare en geskrewe inligting was geidentifiseer. Die lang wagtye en stukkende apparaat is ook gebiede wat verbertering benodig. Algemene gebrek aan komminukasie tussen die verskillende beroepsgroepe, die behoefte aan interpersoonlike lojaliteit en span werk was die hoof bevindinge van die personeel tevredenheidspeiling. Verbeterings maatreels, gefokus op hierdie departementele doelwitte, was geidentifiseer ten eide te verseker dat die KBS voordurend verbeter en in stand gehou word. Samevatting: Alhoewel die departement wel KB prosedures in plek het, voldoen dit nie aan al die criteria vir eksterne akkreditasie nie. Ten einde departementele harmonie en kliente tevredenheid te verseker, met die oog op ISO sertifikasie, moet die departmenteIe doelwitte deurlopend gemeet en verbeter word.

Thesis (MSc)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Planar bone scintigraphy is highly sensitive but it may not be sensitive enough to detect subtle lesions in complex bony structures such as the spine. The accurate anatomic localisation of lesions in regions such as this is also limited using planar images. Single Photon Emission Computed Tomography (SPECT) results in a higher lesion contrast resulting in an improved sensitivity for the detection of subtle lesions. SPECT also enables improved lesion localisation, often valuable in distinguishing benign from malignant disease in the spine. A number of previous studies have demonstrated that the addition of SPECT of the spine significantly enhances the value of bone scintigraphy for the detection of bone metastases compared to planar imaging alone. These studies were however not done in the African context where patients typically present with more advanced disease. In a retrospective study of 576 patients with known primary tumors sent to our institution for bone scintigraphy for the diagnosis of bone metastases, we evaluated 119 patients in whom both planar imaging and SPECT were obtained. The studies were graded for the probability of metastatic disease, and the number of spinal lesions was determined with and without SPECT. The influence of adding SPECT on the interpretation of the study was determined in terms of the reported probability of metastatic disease, the exclusion and confirmation of metastatic disease, the decisiveness of interpretation, and the number of spinal lesions. The addition of SPEeT resulted in a statistically significant change in the interpretation of studies, although the actual numbers of patients affected were relatively small. SPEeT resulted in a more decisive interpretation of bone scintigraphy. There was a significant increase in the number of spinal lesions detected after the addition of SPEeT. It was concluded that although the use of SPEeT is ideal, acceptable results could be achieved using planar imaging alone in this patient population. This is particularly relevant in the African context, where SPEeT is often unavailable or scarce and in great demand. / AFRIKAANSE OPSOMMING: Planare beenflikkergrafie is hoogs sensitief, maar moontlik nie sensitief genoeg om subtiele letsels in ingewikkelde beenstrukture soos die werwelkolom aan te toon nie. Akkurate anatomiese lokalisasie van letsels in die genoemde strukture is beperk wanneer slegs planare beelde gebruik word. Enkelfoton-uitstraling Rekenaartomografie (EFERT) lewer 'n hoër letsel kontras, wat 'n verbeterde sensitiwiteit vir die opsporing van subtiele letsels tot gevolg het. EFERT lei ook tot verbeterde letsel lokalisasie, wat dikwels van waarde is om onderskeid tussen benigne en maligne siekte in die werwelkolom te tref. Reeds met 'n aantal vorige studies is aangetoon dat die toevoeging van EFERT van die werwelkolom die waarde van beenflikkergrafie in die opsporing van beenmetastases beduidend verhoog bo dié van planare beelding alleenlik. Hierdie studies is egter nie in omstandighede eie aan Afrika gedoen nie, waar pasiënte kenmerkend met gevorderde siekte voordoen. In In terugskouende studie van 576 pasiënte met bekende primêre tumore, wat na ons instelling verwys is vir beenflikkergrafie om beenmetastases op te spoor, het ons 119 pasiënte, wat beide planare beelding en EFERT ondergaan het, ge-evalueer. Die studies is gegradeer volgens die waarskynlikheid vir metastatiese siekte, en die hoeveelheid werwelkolom letsels, met en sonder EFERT, is bepaal. Die invloed van EFERT op die vertolking van die studie is bepaal in terme van die waarskynlikheid van metastatiese siekte, die bevestiging en uitskakeling daarvan, die beslistheid van vertolking, en die hoeveelheid werwelkolom letsels. Die toevoeging van EFERT het tot 'n statisties beduidende verandering in die vertolking van studies gelei, alhoewel die werklike getal pasiënte wat hierdeur geraak is, relatief min was. EFERT het 'n meer besliste vertolking van beenflikkergrafie tot gevolg gehad. Daar was 'n beduidende toename in die hoeveelheid werwelkolom letsels wat opgespoor is na die toevoeging van EFERT. Daar is tot die slotsom gekom dat, alhoewel die gebruik van EFERT wenslik is, aanvaarbare resultate met slegs die gebruik van planare beelding in hierdie pasiënt bevolkingsgroep verkry kan word. Dit is veral van belang in Afrikaomstandighede, waar EFERT dikwels onbeskikbaar of skaars is, en ook in groot aanvraag is.

ENGLISH ABSTRACT: Background: The detection of bone infection can be very difficult especially in bone with altered structure due to prior trauma or surgical procedures. Complicated osteomyelitis (COM) is becoming a public health problem especially with the difficult choice between, high cost surgery and prolonged courses of intravenous or oral antibiotic therapy, as well as the social and psychological effect of longterm disease and disability of the patient. The correct localisation of especially bone infection is still a challenge for the clinician. The single photon emission computed tomography/low dose computed tomography (SPECT/CT), by fusing the functional information with the anatomical parts, is a wellestablished tool used in many nuclear medicine studies. This improves the overall quality of the study with more clear answers. The aim of the study was to determine the added value of SPECT/CT in the management of complicated osteomyelitis (COM) in patients with endo-prosthesis, post traumatic osteomyelitis with and without metal implants and diabetic foot. Methods: This was a prospective study, between February 2010 and February 2012. Patients with suspected COM who fulfilled the selection and inclusion criteria were included. All had abnormal three phase bone scan followed by infection imaging with 99mTc labelled white blood cells and 99mTc -colloid if the99mTc labelled white blood cell study was abnormal. 67Ga citrate was used in vertebral involvement. Planar and SPECT/CT images were reviewed for presence of abnormal uptake and for its localization in bone and soft tissue. Scan results were defined as positive or negative. Both planar and SPECT/CT images were compared regarding diagnosis and precise localization of infection. The final diagnosis was obtained from surgical specimen or microbiological culture as well as clinical follow-up of all patients. Results: There were 72 patients, 29 male and 43 female with mean age of 57 yrs [range 27-88].There were 24 patients with prosthesis, 16 with hip prosthesis (PH=16), and 8 with knee prosthesis (PK=8). There were 44 patients with post traumatic osteomyelitis, 26 with metal implants (TOM=26) and 18 without metal implants (TOWM= 18). Four patients had diabetic foot (DF= 4). Infection was diagnosed in 19/72 patients on planar images and in 21/72 on SPECT/CT. Infection was diagnosed in 4 patients with prosthesis, 16 patients with post traumatic injury and one diabetic foot patient. The four patients with prosthesis, SPECT /CT added diagnostic value by excluding osteomyelitis in 3 patients and by defining the exact extent and localizing soft tissue and bone infection (STI/OM) in one patient. In 16 patients with post traumatic OM on planar images, SPECT /CT added diagnostic value, by excluding OM in 4 patients and confirming only STI, better localisation of the uptake in bone and soft tissue in 5 patients, of them 2 patient was negative on planar, and in 7 patients, confirmed and defined the exact extent of both OM and STI. One diabetic foot was positive for STI on the planar, the SPECT/CT added diagnostic value by defining the extent of the infection. In summary the added value of SPECT/CT was: a. Overall infection: 1. Exclusion of osteomyelitis by confirming only soft tissue involvement: 7 patients (10%) 2. Better localization in bone and soft tissue: 6 patients (8%) 3. Better delineation of extent of infection: 9 patients (12%) 4. None: 50 patients (70%) b. In positive cases only: 1. Exclusion of osteomyelitis by confirming only soft tissue involvement: 7 patients (33%) 2. Better localization in bone and soft tissue: 5 patients (24%) 3. Better delineation of extent of infection: 9 patients (43%) 4. None: 0 patients The overall sensitivity, specificity, positive predictive value, negative predictive value and accuracy for infection, on planar was 90%, 100%, 100%, 97%, 97%, respectively and for SPECT/CT 100%, 100%, 100%, 100%, 100%. For OM on planar, the sensitivity, specificity , positive predictive value, negative predictive value and accuracy was 100%, 89%, 53%, 100%, 90%, respectively and for SPECT/CT 100%, 100%, 100%, 100%, 100%. Conclusion: In complicated osteomyelitis, SPECT/CT is useful in localizing, defining the exact extent of infection where the planar images are abnormal, with no added value if the planar images are negative. We recommend in clinical practice the routine use of hybrid SPECT/CT imaging in complicated osteomyelitis when planar images are abnormal. / AFRIKAANSE OPSOMMING: Agtergrond: Die opspoor van beeninfeksie is veral moeilik in been wat as gevolg van vorige trauma of chirurgiese prosedures misvorm is. Gekompliseerde osteomiëlitis word ‘n gesondheidsprobleem veral as gevolg van die moeilike keuse tussen hoë koste chirurgie en langdurige kursusse binneaarse of orale antibiotika, asook die sosiale en sielkundige gevolge van langstaande siekte en die gestremdheid van die pasiënt. Die korrekte lokalisering van veral beeninfeksie is steeds ‘n uitdaging vir die geneesheer. Enkel foton emissie rekenaartomografie / lae dosis rekenaartomografie (SPECT/CT), die kombinasie van funksionele en anatomiese inligting, is ‘n goed gevestigde metode in baie kerngeneeskunde ondersoeke. Dit verbeter die algemene kwaliteit van die studie met ‘n meer spesifieke antwoord. Die doel van hierdie studie was om die bykomende waarde van SPECT/CT in die hantering van gekompliseerde osteomiëlitis in pasiënte met endo-protese, post traumatise osteomiëlitis met en sonder metaal prosteses asook diabetiese voet te bepaal. Metode: ‘n Prospektiewe studie is tussen Februarie 2010 en Februarie 2012 gedoen. Pasiënte met vermoedelik gekompliseerde osteomiëlitis wat aan die keuse en insluitingskriteria voldoen het, is ingesluit. Almal het abnormale drie-fase beenflikkergramme gehad, gevolg deur infeksiebeelding met 99mTc gemerkte witselle en 99mTc kolloïed indien die 99mTc gemerkte witselstudie abnormaal was. 67Ga sitraat is gebruik wanneer daar werwelaantasting teenwoordig was. Die planare en SPECT/CT beelde is vergelyk ten opsigte van diagnose en presiese lokalisering van die infeksie. Die finale diagnose is met behulp van chirurgiese monsters en mikrobiologiese kweking asook die kliniese opvolg van alle pasiënte bepaal. Resultate: Die studie het 72 pasiënte, 29 mans en 43 vroue, met gemiddelde ouderdom van 57 jaar [27 – 88 ingesluit]. Daar was 24 pasiënte met prosteses, waarvan 16 met heupprosteses (PH= 16) en 8 met knieprosteses (PK= 8). Van die 44 pasiënte met post traumatiese osteomiëlitis, het 26 metaal prosteses (TOM= 26) en 18 geen metaalprosteses gehad nie (TOWM= 18). Vier pasiënte het diabetiese voet gehad (DF= 4). By 19/72 van die pasiënte is infeksie op die planare beelde gediagnoseer en in 21/72 op die SPECT/CT beelde. Die bykomende twee gevalle was 1 met TOM en 1 met TOWM. Infeksie is by 4 pasiënte met prosteses, 16 pasiënte met post traumatiese besering en 1 met diabetiese voet gediagnoseer. In die vier pasiënte met prosteses, het SPECT/CT ‘n diagnostiese bydrae gelewer om osteomiëlitis by 3 van die pasiënte uit te skakel en die presiese omvang en lokalisering van sagte weefsel en beeninfeksie (STI/OM) in een pasiënt te bepaal. In 16 pasiënte met post traumatise osteomiëlitis op die planare beelde, was SPECT/CT van diagnostiese waarde, waar osteomiëlitis in 4 pasiënte uitgesluit is, en slegs STI bevestig is. Beter lokalisering van die opname in been en sagte weefsel was in 5 pasiënte moontlik, van wie 2 op die planare beelde negatief was, en in 7 pasiënte bevestig en die presiese omvang met beide OM en STI gedefinieer is. Een diabetiese voet was positief vir STI op die planare beelde, maar die SPECT/CT het diagnostiese waarde verbeter deur die omvang van die infeksie beter te toon. Ter opsomming, was die waarde van die SPECT/CT: 1. Uitsluiting van osteomiëlitis deur slegs van sagte weefsel aantasting te bevestig: 7 pasiënte 10% 2. Beter lokalisering in been en sagte weefsel: 5 pasiënte 7% 3. Beter definisie van omvang van infeksie: 9 pasiënte 12% 4. Geen bykomende waarde: 51 pasiënte 71% Die algehele sensitiwiteit, spesifisiteit, positiewe voorspellingswaarde, negatiewe voorspellingswaarde en akkuraatheid vir die opspoor van infeksie vir die planare beelde was 90%, 100%, 100%, 97%, 97%, onderskeidelik en vir die SPECT/CT 100%, 100%, 100%, 100% en 100%. Vir osteomiëlitis was sensitiwiteit, spesifisiteit, positiewe voorspellingswaarde, negatiewe voorspellingswaarde en akkuraatheid van planare beelde 100%, 89%, 53%, 100%, 90%, onderskeidelik en die van SPECT/CT 100%, 100%, 100%, 100% , 100%. Gevolgtrekking: SPECT/CT is nuttig in die lokalisering en definiëring van die presiese omvang van die infeksie in gekompliseerde osteomiëlitis in gevalle waar die planare beelde abnormaal is, met geen bykomende waarde wanneer planare beelde negatief is nie. Ons beveel SPECT/CT beelding as roetine in kliniese praktyk aan wanneer planare beelde in gekompliseerde osteomiëlitis abnormaal is.

Thesis (MSc (Medical Imaging and Clinical Oncology. Nuclear Medicine))--University of Stellenbosch, 2010. / ENGLISH SUMMARY: Introduction: Bone scintigraphy is used extensively in evaluating metastatic disease. There are currently no clear recommendations for the use of SPECT/CT in metastatic bone disease. Existing procedural guidelines from the Society of Nuclear Medicine (SNM) for SPECT/CT do not provide specific indications for use of SPECT/CT in bone scintigraphy, and there are currently no other guidelines for the use of SPECT/CT in bone scintigraphy that the author is aware of. The aim of this study was to investigate the additional value of SPECT/CT, and to identify the clinical indications for which SPECT/CT is most useful in patients with suspected bone metastases. Subjects and Methods: Forty-two patients with equivocal lesions on planar scintigraphy were prospectively recruited and planar imaging, SPECT, and SPECT/CT done on all patients. On reading of SPECT and then SPECT/CT, patients and individual lesions were classified as malignant, benign or equivocal. Radiological studies and available clinical information were also used during reading of scans. Review of clinical information, radiological studies and/or follow-up bone scans were used as gold standard. The results of the SPECT and SPECT/CT were compared in terms of proportion of equivocal findings and accuracy. Results: Forty-two patients with 189 skeletal lesions were examined. There was a diverse variety of primary tumours, although the majority had breast (n=22) or prostate cancer (n=8). Overall, SPECT/CT resulted in a significant reduction in the proportion of equivocal findings on both a patient-wise (p=0.0015) and lesion-wise basis (p<0.0001). The overall accuracy of SPECT/CT was significantly higher than that of SPECT on both a patient-wise (p=0.0026) and lesion-wise basis (p<0.0001). Generally SPECT/CT decreased the proportion of equivocal findings and increased the accuracy independent of the presence of bone pain, type of primary tumour, or skeletal region involved. SPECT/CT did not significantly improve the diagnostic confidence of readers in equivocal lumbar lesions although accuracy was significantly improved in this region. Conclusion: SPECT/CT performs significantly better than SPECT alone for the interpretation of equivocal planar lesions. There is no evidence that the benefit of SPECT/CT is dependent on the type of primary tumour or the presence of bone pain. Where resources are limited, SPECT/CT is indicated only in those patients in whom correct classification of the lesions in question is expected to alter the patient’s management. SPECT/CT images should be interpreted with the aid of a diagnostic radiologist or nuclear medicine physicians should acquire sufficient experience in Computed Tomographic image interpretation in order to optimise diagnostic benefit from SPECT/CT. / AFRIKAANSE OPSOMMING: Inleiding: Beenflikkergrafie word wyd vir die evaluering van metastatiese siekte gebruik. Daar bestaan tans geen duidelike aanbevelings vir die gebruik van Enkelfotonemissie rekenaartomografie gekombineer met rekenaartomografie (EFERT/RT, Engels SPECT/CT) in metastatiese beensiekte nie. Bestaande riglyne van die Amerikaanse Society of Nuclear Medicine (SNM) vir EFERT/RT gee nie spesifieke indikasies vir die gebruik van EFERT/RT in beenflikkergrafie nie, en daar is tans geen ander riglyne waarvan die outeur bewus is nie. Die doel van hierdie studie was om die bykomende waarde van EFERT/RT te ondersoek, en om dié kliniese indikasies waar EFERT/RT in pasiënte met vermoedelike beenmetastases mees nuttig sal wees, te identifiseer. Pasiënte en Metodes: Twee en veertig pasiënte met twyfelagtige letsels op planare skeletflikkergrafie is prospektief geselekteer en planare beelding, EFERT en EFERT/RT is op alle pasiënte gedoen. Tydens beoordeling van EFERT en daarna EFERT/RT beelde is pasiënte en individuele letsels as maligne, benigne of twyfelagtig geklassifiseer. Radiologiese studies en beskikbare kliniese inligting is ook tydens interpretasie van flikkergramme gebruik. Kliniese inligting, radiologiese studies en/of opvolg beenflikkergramme is as goue standaard gebruik. Die resultate van EFERT en EFERT/RT is ten opsigte van die aantal twyfelagtige bevindings en akkuraatheid vergelyk. Resultate: Twee en veertig pasiënte met 189 skeletale letsels is ondersoek. Daar was ‘n verskeidenheid van primêre tumore, maar die meerderheid van pasiënte het borsvi (n=22) of prostaatkanker (n=8) gehad. Die gebruik van EFERT/RT het gelei tot ‘n betekenisvolle afname in die aantal twyfelagtige bevindings, beide op ‘n pasiënt- en ‘n letselbasis (p=0.0015 en p<0.0001 onderskeidelik). Die algehele akkuraatheid van EFERT/RT was betekenisvol hoër as die van EFERT alleen, beide op pasiënt- en op letselbasis (p=0.0026 en p<0.0001 onderskeidelik). Oor die algemeen het EFERT/RT die aantal twyfelagtige letsels verminder en die akkuraatheid verhoog, ongeag die teenwoordigheid van beenpyn, die tipe primêre tumor of die area van die skelet wat betrokke was. In twyfelagtige lumbale letsels het EFERT/RT nie die diagnostiese vertroue van beoordelaars van flikkergramme verhoog nie, alhoewel die akkuraatheid vir hierdie gebied wel betekenisvol toegeneem het. Gevolgtrekking: EFERT/RT vaar betekenisvol beter as EFERT in die beoordeling van twyfelagtige letsels op planare beenflikkergramme. Daar is geen bewys dat die voordeel van EFERT/RT afhanklik is van die tipe primêre tumor of die teenwoordigheid van beenpyn nie. Waar hulpbronne beperk is, is EFERT/RT slegs aangedui in dié pasiënte waar verwag word dat korrekte klassifikasie van die betrokke letsel behandeling sal beïnvloed. EFERT/RT beelde behoort met die hulp van ‘n diagnostiese radioloog beoordeel te word, of kerngeneeskundiges moet genoegsame ondervinding in die interpretasie van rekenaartomografiebeelde hê om die diagnostiese voordeel van EFERT/RT optimaal te kan benut.

Thesis (MScMed)--Stellenbosch University, 2004. / Copy not signed by author. / ENGLISH ABSTRACT: This study involved 33 patients, 19 men and 14 women. The age range was wide (20-90 years) and median age was 57 years. These patients had a single pulmonary nodule (SPN) defined radiologically as a well defined, round or oval intrapulmonary lung lesion not associated with atelectasis or adenopathy on chest radiography or computed tomography. Patients were investigated with Tc-99m MIBI and TI-201 (25 patients) and with Tc-99m MIBI alone (8 patients). Single photon emission computed tomography images were reconstructed using both iterative reconstruction (Ordered Subsets - Expectation Maximisation: aSEM) and filtered backprojection (FBP), on the Hermes system. Transverse, coronal and sagittal slices were displayed on the screen using a grey scale. The aSEM and FBP images for each study were co-registered semi-automatically using the multimodality programme on the Hermes. The best slice for the lesion was chosen according to the best view used to locate the SPN on chest radiograph. Regions of interest (Ral) were drawn manually outside the outer margin of the detected lesion, first on the aSEM image. This was automatically mirrored on the co-registered FBP image. For most patients, the background was automatically mirrored horizontally on the contralateral side, again, first on the OSEM then automatically on the FBP image. Automatic vertical mirroring or manual horizontal mirroring was used when background was found to be in a visually 'hot' area like the heart or vertebrae. The average counts and standard deviation of the Ral and background were generated automatically. Semi-quantitative image analysis was done by calculating the signal-to-noise ratio (SNR) and tumour-to-background (TIB) ratio using the following formulae: SNR = Mean counts ROI(lesion) - Mean counts background Standard deviation background TIB rati.o = -M---e-a-n-'--c-o--u-n-'t-s- ROI(lesion) Mean counts background Detection was found to be the same for the two reconstruction algorithms, that is, every lesion detected by using OSEM could also be detected by using FBP. However lesion detection did differ between Tl-201 and Tc-99m-MIBI. Sensitivity and specificity were calculated for different thresholds of SNR and TIB ratios. Receiver operating characteristics (ROC) curves were drawn to represent the different sensitivities and specificities at each threshold. Tuberculosis (TB) was not included in this analysis as uptake of Tl-20l was found to be significantly high and comparable to that of malignant nodules. However the effect of OSEM and FBP on the 'positive' TB nodules was assessed separately. By calculating the area under the ROC curves, TI-201 using OSEM was shown to be more accurate at differentiating malignant nodules from benign ones than FBP. Although this difference was not statistically significant (p=0.1 0), there was a clear tendency. The two reconstruction algorithms were found to be almost equally accurate, when using Tc-99m-MIBI, the difference between them being considerably insignificant. In conclusion, it was shown that there is a tendency that OSEM outperforms FBP for studies using Tl-201 but not for Tc-99m-MIBI. / AFRIKAANSE OPSOMMING: Hierdie studie sluit 33 pasiënte in, 19 mans en 14 vroue. Die ouderdomme wissel tussen 20 en 90 jaar met 'n gemiddelde ouderdom van 57 jaar. Elkeen van die pasiënte het 'n enkel longnodule (SPN) op borskas X-straal en/of rekenaar tomografie getoon, wat radiologies gedefinieer word as 'n goed omskrewe, ronde of ovaal intrapulmonale longletsel wat nie met atelektase of adenopatie geassosieer is nie. Pasiënte is met Tc-99m MIDI en TI-201 (25 pasiënte) of slegs met Tc-99m MIBI (8 pasiënte) ondersoek. Enkelfoton emissie rekenaar tomografiese (EFERT) beelde is met beide iteratiewe rekonstruksie (Ordered Subsets - Expectation Maximisation: OSEM) en gefilterde terugprojeksie (FBP) met die Hermes sisteem gerekonstrueer. Transvers, koronale en sagittale snitte is in grysskaal op die sisteem vertoon. Die OSEM en FBP beelde vir elke studie is semi-outomaties gekoregistreer met behulp van die multimodaliteitsprogram op die Hermes. Die optimale snit vir elke letsel is gekies volgens die beste aansig op die borskas X-straalom die SPN te lokaliseer. Gebiede van belang (ROl) is met die hand buite-om die buitenste rand van die letsel getrek op die OSEM beeld en daarna outomaties in die ooreenstemmende area op die gekoregistreerde FPB beeld geplaas. Vir die meeste pasiënte is die agtergrond outomaties as horisontale spieëlbeeld op die kontralaterale kant geplaas, eers op die OSEM en dan outomaties op die FBP beeld. 'n Outomatiese vertikale spieëlbeeld of manuele horisontale verskuiwing van die agtergrondsarea is gedoen indien die agtergrond oorvleuel het met 'n 'warm' area soos die hart of werwels. Die gemiddelde tellings en standaardafwyking van die ROl en agtergrond is outomaties gegenereer. Semi-kwantitatiewe beeldanalise is gedoen deur berekening van die sein-tot-agtergrond verhouding (signal-to-noise ratio - SNR) en tumor-tot-agtergrond (TIB) verhouding met behulp van die volgende formules: SNR = gemiddelde tellings ROI(letsel) - gemiddelde tellings agtergrond Standaard afwyking van agtergrond TIB rati.o = -g=em--id-d-e-l-d-e--te=ll-in-g-s__R:_O-I(-le-t-s'e-l) gemiddelde tellings agtergrond Opsporing is soortgelyk bevind vir die twee rekonstruksie algoritmes, dit wil sê elke letselopgespoor met behulp van OSEM kon ook met FBP opgespoor word. Letselwaameming het egter verskil tussen TI-201 en Tc-99m-MIBI. Sensitiwiteit en spesifisiteit is vir verskillende drempels van SNR en TIB verhoudings bereken. 'Receiver operating characteristics' (ROC) kurwes is getrek om die verskillende sensitiwiteite en spesifisiteite by elke drempel te verteenwoordig. Tuberkulose (TB) is nie in hierdie analise ingesluit nie aangesien opname van Tl-201 beduidend hoog en vergelykbaar met die van maligne nodules was. Die effek van OSEM en FBP op die 'positiewe' TB nodules is egter apart beoordeel. Deur berekening van die area onder die ROC kurwes, is getoon dat OSEM van Tl-201 tomografiese data meer akkuraat as FBP was om maligne van benigne nodules te onderskei. Alhoewel hierdie verskil nie statisties betekenisvol was nie (p=0.10), is daar wel 'n duidelike neiging gevind. Die twee rekonstruksie algoritmes was byna ewe akkuraat wanneer Tc-99m-MIBI gebruik is, met duidelik geen betekenisvolle verskil tussen die algoritmes nie. Gevo lgtrekking In hierdie studie is dit getoon dat daar 'n neiging is dat OSEM beter vaar as FBP vir studies met tallium-201 maar nie vir Tc-99m-MIBI nie.

Thesis (MMed)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Background: Hybrid imaging using single photon emission computed tomography/low dose (x-ray) computed tomography (SPECT/LDCT) is of benefit in preoperative scintigraphy of primary hyperparathyroidism. The role of SPECT/LDCT in preoperative assessment of renal hyperparathyroidism has not yet been examined. The aim of the study was to determine whether SPECT/LDCT conferred any benefit over SPECT alone in terms of detection and/or localization of hyperfunctioning parathyroid tissue in this patient group. Methods: A retrospective study of patients with renal hyperparathyroidism and positive planar and SPECT scintigraphy was undertaken. All patients underwent planar scintigraphy using 99mTc-pertechnetate immediately followed by 99mTc-sestamibi as well as SPECT/LDCT 60 min after sestamibi injection and a delayed static image to assess for differential washout at 2-3 hours. Planar subtraction images were generated. For each patient, two nuclear physicians reported on planar+ SPECT images followed by planar + SPECT/LDCT images (assisted by a radiologist). Confidence for the presence of hyperfunctioning parathyroid tissue as well as confidence of location was scored on a Likert-type scale. Interpretation of planar + SPECT was compared with interpretation of planar + SPECT/LDCT. The impact of LDCT on equivocal lesions and number of ectopic lesions detected was also assessed. Results: Twenty patients (M:13; F:7) imaged between February 2008 and June 2011 were included [mean age: 40 years (24 – 55)]. Mean creatinine was 687 μmol/l (169-1213), mean corrected calcium: 2.55 mmol/l (1.95-3.33) and median PTH 167 pmol/l (2.4 - >201). Thirty-five lesions were detected on planar and SPECT and this was unchanged after assessment of the LDCT data. Confidence for the presence of parathyroid pathology changed in 5 patients (5 lesions) with the addition of LDCT. LDCT changed the mean confidence of parathyroid pathology from 3.17 to 3.29 (p=0.16). Addition of LDCT reduced the number of equivocal lesions from 18 (14 patients) to 14 (10 patients) (p=0.13). The addition of LDCT changed localization in 4 lesions (3 patients). Confidence in localization of pathology changed in 9 lesions (7 patients) and the mean localization confidence score was improved from 4.2 to 4.46 (p=0.002) with LDCT. The number of lesions classified as ectopic increased from 5 (on planar+SPECT) to 8 (with addition of LDCT) (p=0.25). Conclusion: In renal hyperparathyroidism SPECT/LDCT altered localization of lesions detected on planar and SPECT alone and improved reader confidence of localization accuracy. SPECT/LDCT conferred no additional benefit over SPECT in terms of detection, confidence of parathyroid pathology or ability to distinguish equivocal from non-equivocal parathyroid lesions. The addition of LDCT did not detect significantly more ectopic lesions. Whereas the minor improvement in reader confidence of localization (with addition of LDCT) was of questionable clinical significance, we speculate that the changed and presumably improved localization of lesions on SPECT/LDCT had potential clinical impact in a significant proportion of patients. On this basis we recommend the use of hybrid SPECT/LDCT in imaging of renal hyperparathyroidism when surgery is considered. / AFRIKAANSE OPSOMMING: Agtergrond: Hibriedbeelding met enkelfoton emissie rekenaartomografie / lae dosis rekenaartomografie (EFERT/LDRT) is voordelig in pre-operatiewe beelding van primêre hiperparatiroïedisme. Die rol van EFERT/RT in pre-operatiewe evaluering van renale hiperparatiroïedisme is nog nie ondersoek nie. Die doel van hierdie studie was om in hierdie pasiëntgroep te bepaal of EFERT/RT 'n voordeel bo EFERT alleen verleen. Metode: 'n Retrospektiewe studie van pasiënte met renale hiperparatiroïedisme en positiewe planare en EFERT flikkergrafie is onderneem. Na die toediening van 99mTc-pertegnetaat is planare beelding op alle pasiënte gedoen, onmiddellik gevolg deur 99mTc-sestamibi sowel as EFERT/RT beelding 60 min na sestamibi inspuiting en 'n laat statiese beeld vir differensiële uitwas op 2-3 uur. Planare subtraksiebeelde is verkry. Twee kerngeneeskundiges het die planare + EFERT beelde van elke pasiënt gerapporteer, waarna die planare + EFERT/RT beelde met die hulp van 'n radioloog gerapporteer is. Sekerheid oor die teenwoordigheid van hiperfunksionerende paratiroïedweefsel sowel as die sekerheid oor die lokalisering daarvan, is op 'n Likert-tipe skaal verkry. Interpretasie van planare + EFERT is vergelyk met die interpretasie van planare + EFERT/RT. Die impak van LDRT op twyfelagtige letsels en die aantal ektopiese letsels waargeneem, is ook bepaal. Resultate: Twintig pasiënte (M:13; F:7) met beelding tussen Februarie 2008 en Junie 2011 is ingesluit [gemiddelde ouderdom: 40 jaar (24-55)] . Die gemiddelde kreatinien was 687 μmol/l (169-1213), gemiddelde gekorrigeerde kalsium 2.55 mmol/l (1.95-3.33) en mediaan PTH 167 pmol/l (2.4->201). Vyf en dertig letsels is op planare en EFERT beelde waargeneem en was onveranderd na assessering van die LDRT-data. Sekerheid oor die teenwoordigheid van paratiroïedpatologie het verander in 5 pasiënte (5 letsels) met die toevoeging van LDRT. LDRT het die gemiddelde sekerheid van paratiroïedpatologie van 3.17 tot 3.29 verander (p = 0.16). Toevoeging van LDRT het die aantal twyfelagtige letsels van 18 (14 pasiënte) tot 14 (10 pasiënte) verminder (p = 0.13). Die byvoeging van LDRT het die lokalisering in 4 letsels (3 pasiënte) verander. Sekerheid oor die lokalisering van patologie is in 9 letsels (7 pasiënte) verander en die gemiddelde lokalisering betroubaarheidswaarde is verbeter van 4.2 tot 4.46 (p = 0.002) met LDRT. Met die byvoeging van LDRT het die aantal letsels geklassifiseer as ektopies van 5 tot 8 (p = 0.25) toegeneem. Gevolgtrekking: In renale hiperparatiroïedisme het EFERT/RT die lokalisering van letsels wat op planare + EFERT beelding alleen waargeneem is, verander en die leser se vertroue om akkuraat te lokaliseer verbeter. EFERT/LDRT het geen bykomende voordeel bo EFERT in terme van die opsporing, sekerheid van paratiroïedpatologie of onderskeidingsvermoë tussen twyfelagtige teenoor nie-twyfelagtige paratiroïedletsels verleen nie. Met die byvoeging van LDRT is nie beduidend meer ektopiese letsels gevind nie. Terwyl die geringe verbetering in die sekerheid van lokalisering (met die byvoeging van LDRT) van twyfelagtige kliniese betekenis was, spekuleer ons dat die verandering en vermoedelik verbeterde lokalisering van letsels op EFERT/LDRT ʼn potensiële kliniese impak het in 'n beduidende aantal pasiënte. Die gebruik van EFERT/LDRT in die beelding van renale hiperparatiroïedisme wanneer chirurgie oorweeg word, word dus vir bogenoemde rede aanbeveel.