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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The added value of SPECT/CT in complicated osteomyelitis

Tag, Naima 12 1900 (has links)
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.
12

A retrospective analysis of the utility of myocardial perfusion imaging using single photon emission computed tomography (SPECT) for differentiating ischaemic from non-ischaemic left ventricular dysfunction

Singh, Alosha January 2017 (has links)
A research report submitted to the Faculty of Health Sciences in fulfilment of the requirements for the degree of Master of Medicine, in Internal Medicine at the University of Witwatersrand, Johannesburg. September 2017 / Differentiating ischaemic left ventricular dysfunction (ILVD) from non-ischaemic left ventricular dysfunction (NILVD) is crucial since appropriately selected patients may benefit from coronary revascularisation. The aim of this study was to evaluate the diagnostic utility of myocardial perfusion imaging (MPI) in patients presenting with left ventricular dysfunction using coronary angiography (CA) as the gold standard. Methods This single centre retrospective study was conducted in 52 patients with heart failure with a reduced ejection fraction (EF< 40%) who had both MPI as well as CA at CHBAH between January 2005 and December 2012. ILVD was diagnosed when the distribution and severity of coronary disease on CA was sufficient to account for the degree of left ventricular dysfunction. Results From a total of 52 patients, 33 (63%) had ILVD and 19 (37%) had NILVD. As compared to patients with NILVD, those with ILVD were more likely to be Indian and White (p=0.0014), have more coronary risk factors (5(2) vs 3(2), p < 0.0001) and more commonly have q waves on the ECG (0% vs 55%, p < 0.0001). MPI had a sensitivity of 100% (95% CI 66-100%) and specificity of 52.63% (95% CI 30.18 - 75.08) for the diagnosis of ILVD. The presence of fixed perfusion defects on MPI was the best predictor of ILVD. Conclusion MPI has high sensitivity but low specificity for the diagnosis of ILVD. This makes it a useful screening test for the exclusion of coronary artery disease in patients presenting with heart failure. / MT2018
13

Splitting Frames Based on Hypothesis Testing for Patient Motion Compensation in SPECT

MA, LINNA 30 August 2006 (has links)
"Patient motion is a significant cause of artifacts in SPECT imaging. It is important to be able to detect when a patient undergoing SPECT imaging is stationary, and when significant motion has occurred, in order to selectively apply motion compensation. In our system, optical cameras observe reflective markers on the patient. Subsequent image processing determines the marker positions relative to the SPECT system, calculating patient motion. We use this information to decide how to aggregate detected gamma rays (events) into projection images (frames) for tomographic reconstruction. For the most part, patients are stationary, and all events acquired at a single detector angle are treated as a single frame. When a patient moves, it becomes necessary to split a frame into subframes during each of which the patient is stationary. This thesis presents a method for splitting frames based on hypothesis testing. Two competing hypotheses and probability model are designed. Whether to split frames is based on a Bayesian recursive estimation of the likelihood function. The estimation procedure lends itself to an efficient iterative implementation. We show that the frame splitting algorithm performance is good for a sample SNR. Different motion simulation cases are presented to verify the algorithm performance. This work is expected to improve the accuracy of motion compensation in clinical diagnoses."
14

Interactive, quantitative 3D stress echocardiography and myocardial perfusion spect for improved diagnosis of coronary artery disease

Walimbe, Vivek S., January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 143-150).
15

Observational signatures of the first stars : from the near infrared background to Lyman-[alpha] emitters

Fernandez, Elizabeth Rose 11 September 2012 (has links)
Not available / text
16

Premenstrüel disforik bozukluk tanısı alan kadınlarda bölgesel beyin kan akımı değişikliklerinin Tc-99m HMPAO Beyin Perfüzyon SPECT ile değerlendirilmesi /

Özbek, Feride Meltem. Çerçi, Sevim Süreyya. January 2007 (has links) (PDF)
Tez (Tıpta Uzmanlık) - Süleyman Demirel Üniversitesi, Tıp Fakültesi, Nükleer Tıp Anabilim Dalı, 2007. / Bibliyografya var.
17

Observational signatures of the first stars from the near infrared background to Lyman-[alpha] emitters /

Fernandez, Elizabeth Rose. January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.
18

Splitting frames based on hypothesis testing for patient motion compensation in SPECT

Ma, Linna. January 2006 (has links)
Thesis (M.S.) -- Worcester Polytechnic Institute. / Keywords: Hypothesis testing; motion compensation; SPECT. Includes bibliographical references (leaves 30-31).
19

Prediction of neurosensory disability in very low birth weight preterm infants:structural and functional brain imaging and hearing screening at term age and follow-up of infants to a corrected age of 18 months

Valkama, M. (Marita) 06 March 2001 (has links)
Abstract The objectives were to study ultrasound (US), magnetic resonance imaging (MRI), single photon emission tomography (SPET) and brainstem auditory evoked potentials (BAEP) as structural and functional imaging methods for the prediction of later neuromotor outcome and to assess the reliability of auditory brainstem responses (ABR), transient evoked otoacoustic emissions (TEOAE) and free-field auditory behavioural responses (FF) for the prediction of permanent hearing loss. The series comprised 51 surviving very low birth weight preterm infants born at &lt; 34 gestational weeks with a birth weight &lt; 1500 grams, taking 52 full-term infants as controls with respect to hearing screening and 21 with respect to brainstem function. The imaging examinations and hearing screening were performed at term age and follow-up continued to a corrected age of 18 months for the evaluation of neurodevelopment and hearing. MRI images were analysed with regard to the degree of myelination, parenchymal lesions, ventricular-brain ratios and widths of the extracerebral spaces, and the predictive value of the findings for later neuromotor development was assessed by comparison with US. In the SPET examinations (on 34 infants) relative regional perfusion levels and hemispheric asymmetries were evaluated in slices. The predictive value of perfusion defects in SPET was similarly assessed relative to US abnormalities. Brainstem size was measured by MRI, and brainstem function evaluated by BAEP, and results being used to predict neurosensory disability. Hearing was screened by means of TEOAE, ABR and FF, and the results used to predict permanent hearing loss. Parenchymal lesions in MRI predicted cerebral palsy (CP) with a sensitivity of 82% and a specificity of 97%, the corresponding figures for US being 58% and 100%. Delayed myelination, ventricular-brain ratios and widths of the extracerebral spaces failed to predict CP. The sensitivity of perfusion defects in SPET for predicting CP was 82% and the specificity 70%, and correspondingly US attained a sensitivity of 73% and a specificity of 83%. The best brainstem dimensions for predicting neurosensory disability reached at sensitivity of 23-31% and a specificity of 97-100%. The best predictors in BAEP gave the sensitivity of 93% with a specificity of 57-59%. Bilateral failure in TEOAE predicted hearing loss with a sensitivity of 50% and with a specificity of 84%, and that in ABR with a sensitivity of 100% and a specificity of 98%. The FF examination showed a sensitivity of 50% and a specificity of 98%. In conclusion, out of the brain imaging methods used here MRI was the best for predicting abnormal neuromotor outcome. Brainstem dimensions in MRI appear to predict neurosensory disability poorly, however, whereas BAEP shows a better prediction value, but is limited by a low specificity. ABR seems to be the best hearing screening method because it includes retrocochlear involvements in preterm infants.
20

Noninvasive longitudinal quantification of β-cell mass with [111In]-labeled exendin-4 / 111In標識exendin-4を用いた、非侵襲的かつ縦断的なベータ細胞量の定量

Fujita, Naotaka 23 January 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22149号 / 医博第4540号 / 新制||医||1039(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 川口 義弥, 教授 上本 伸二, 教授 富樫 かおり / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

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