Abstract Subarachnoid haemorrhage (SAH) is a life-threatened disease with poor outcome. It is usually caused by an intracranial aneurysm (IA) rupture and rapid diagnosis and treatment are of great importance. Computed tomography (CT) is a reliable method to detect the blood in the subarachnoid (SA) spaces. Digital subtraction angiography (DSA) offers dynamic and morphological information of a ruptured IA. The treatment options for excluding an aneurysm from the main circulation are neurosurgical clipping and endovascular procedures. The purpose of the present study was to evaluate the risk factors of acute hydrocephalus (HC) and the reliability to localize the ruptured aneurysm based on non-contrast CT. The aim was also to compare the effect of neurosurgical and endovascular treatment on the development of chronic HC, and evaluate the incidence and the risk factors of early rebleeding (<  30 days) after coiling. The data of 180 operated patients with a ruptured IA were checked. Two neuroradiologists separately located the IAs based on non-contrast CT. The analyses of blood amount and distribution was a reliable method for estimating the location of ruptured middle cerebral artery (MCA) aneurysms and anterior communicate artery (ACoA) aneurysms. Intracerebral haemorrhage (ICH) was a predictor for detecting the precise site. The results confirmed that intraventricular haemorrhage (IVH) was the most consistent single risk factor for the development of acute HC. Haemorrhage in the basal region and the large total blood amount in the SA spaces were strong predictors. The effect of early treatment modality for ruptured IAs on the development of chronic HC with 102 clipped and 107 coiled patients was compared. The treatment method used was not significantly associated with the occurrence of chronic HC or the need for shunt operation. The incidence and risk factors of early rebleeding after coiling were investigated in 194 consecutive acutely (within 3 days) coiled patients with ruptured IAs. The incidence of early rehaemorrhage was 3.6%. The presence of ICH at admission and poor clinical condition were significant predictors for rebleeding. An early rehaemorrhage appeared as an enlargement of the ICH in all of these patients. In conclusion, the non-contrast CT is a reliable method to detect the location of ruptured IA in patients with MCA and ACoA aneurysms. The risk factor for the development of acute HC is IVH. Other predictors are the total SA blood amount and blood in the basal regions. The treatment method used for acutely ruptured IA has no significant effect on the occurrence of chronic HC. The incidence of early rebleeding after coiling is low. The risk factors of rebleeding are the presence of ICH and poor clinical condition. Rehaemorrhage appears often as an enlargement of the ICH.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22339号 / 医博第4580号 / 新制||医||1042(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 木村 剛, 教授 髙橋 良輔, 教授 小池 薫 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

abstract: Cerebral aneurysms are pathological balloonings of blood vessels in the brain, commonly found in the arterial network at the base of the brain. Cerebral aneurysm rupture can lead to a dangerous medical condition, subarachnoid hemorrhage, that is associated with high rates of morbidity and mortality. Effective evaluation and management of cerebral aneurysms is therefore essential to public health. The goal of treating an aneurysm is to isolate the aneurysm from its surrounding circulation, thereby preventing further growth and rupture. Endovascular treatment for cerebral aneurysms has gained popularity over traditional surgical techniques due to its minimally invasive nature and shorter associated recovery time. The hemodynamic modifications that the treatment effects can promote thrombus formation within the aneurysm leading to eventual isolation. However, different treatment devices can effect very different hemodynamic outcomes in aneurysms with different geometries. Currently, cerebral aneurysm risk evaluation and treatment planning in clinical practice is largely based on geometric features of the aneurysm including the dome size, dome-to-neck ratio, and parent vessel geometry. Hemodynamics, on the other hand, although known to be deeply involved in cerebral aneurysm initiation and progression, are considered to a lesser degree. Previous work in the field of biofluid mechanics has demonstrated that geometry is a driving factor behind aneurysmal hemodynamics. The goal of this research is to develop a more combined geometric/hemodynamic basis for informing clinical decisions. Geometric main effects were analyzed to quantify contributions made by geometric factors that describe cerebral aneurysms (i.e., dome size, dome-to-neck ratio, and inflow angle) to clinically relevant hemodynamic responses (i.e., wall shear stress, root mean square velocity magnitude and cross-neck flow). Computational templates of idealized bifurcation and sidewall aneurysms were created to satisfy a two-level full factorial design, and examined using computational fluid dynamics. A subset of the computational bifurcation templates was also translated into physical models for experimental validation using particle image velocimetry. The effects of geometry on treatment were analyzed by virtually treating the aneurysm templates with endovascular devices. The statistical relationships between geometry, treatment, and flow that emerged have the potential to play a valuable role in clinical practice. / Dissertation/Thesis / Doctoral Dissertation Bioengineering 2016

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22037号 / 医博第4522号 / 新制||医||1038(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 髙橋 良輔, 教授 湊谷 謙司, 教授 井上 治久 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DGAM

The aneurysma of abdominal aorta is a pathological amplification of the diameter of this artery. It is a serious illness which affects 2 -- 6 % men and 1 -- 2 % women over 60. In the case of a rupture there is the mortality of 80 -- 90 %. If the aneurysma is diagnosed in time it is necessary to solve this state with an adequate treatment. The surgical treatment consists in substitution of the afflected part with a vessel replacement. Thanks to the development of medicinal technologies the aorta aneurysma is more and more often treated by the help of stentgrapth by which the afflicted part of the aorta is set aside from the circulation. The theoretical (the first) part of this work deals with the issues of the aneurysma of abdominal aorta, and it also describes the methods of its treatment. Then the work describes costs analyses used in the medical service. The practical part of the work is dedicated to the cost analysis of the treatment by means of a cost minimalization method. The work processes data of a group of patients being treated during a certain period of time in the Olomouc University Hospital in the Department of Vessel Surgery and in the Department of Interventional Radiology. The aim of this work is to evaluate and compare objectively the costs of abdominal aorta aneurysma treatment by individual methods, and to compare the results with foreign studies.

Aspectos morfológicos do nido e embolização parcial neoadjuvante sem intenção de cura de malformações arteriovenosas encefálicas, precedendo a radiocirurgia, podem ter influência no resultado final do tratamento. Métodos: série consecutiva de 47 pacientes submetidos à radiocirurgia (1 a 5 sessões), precedida ou não por embolização com cianoacrilato. Acompanhamento clínico e radiológico mínimo de 36 meses. Resultados: a apresentação hemorrágica ocorreu em 68,1% dos pacientes tratados; destes, 62,5% portavam fístula arteriovenosa dentro da malformação arteriovenosa; 83,3% ectasia venosa e 90% restrição à drenagem venosa. A taxa de oclusão de embolização seguida de radiocirurgia foi de 46,1% e da radiocirurgia isolada foi de 52,4% (p=0,671). Foram identificados como fatores favoráveis à oclusão: baixo volume nidal, ausência de fístula arteriovenosa intranidal, maior dose de radiação e baixo grau na classificação das malformações arteriovenosas encefálicas baseadas na radiocirurgia (RBAS). Conclusões: o menor volume nidal (p < 0,001), o menor grau na escala RBAS (p=0,047), a ausência de fístula arteriovenosa intranidal (p=0,001) e a maior dose prescrita (p=0,001) tiveram correlação com resultado favorável no tratamento. Embolização seguida de radiocirurgia não foi superior à radiocirurgia isolada (p=0,772). A eliminação de fístulas arteriovenosas intranidais pela embolização pode aumentar a eficácia da radiocirurgia / Partial nidal embolization preceding radiosurgery of brain arteriovenous malformations (AVM) and some morphological nidal features may be related to final results. Methods: Analysis of a longitudinal cohort of 47 consecutive patients who underwent radiosurgery preceded or not by embolization. Embolizations were performed exclusively with n-butyl cyanoacrylate. Radiosurgery was delivered either as a single or divided up to 5 equal fractions. Clinical and radiological follow up of at least 36 months was obtained. Results: Hemorrhagic presentation was seen in 68.1% of the cases; 62.5% harbored intranidal arteriovenous fistulas (AVF), 83.3% had venous ectasias and 90% had venous outflow stenosis. The occlusion rate of embolization plus radiosurgery was 46.1% and radiosurgery alone was 52.4% (p = 0.671). Variables significantly associated with obliteration were lower nidus volume, lack of intranidal arteriovenous fistula, higher radiosurgical dose and lower grades in radiosurgical-based AVM scale (RBAS). Conclusions: a small nidus (p < 0.001), a lower RBAS grade (p = 0.047), no intranidal AVF (p = 0.001) and greater radiosurgical dose (p = 0.001) were associated to better results. Embolization followed by radiosurgery was not superior to radiosurgery alone (p = 0.772). Endovascular elimination of intranidal AVF\'s may help to promote radiosurgical occlusion

Aspectos morfológicos do nido e embolização parcial neoadjuvante sem intenção de cura de malformações arteriovenosas encefálicas, precedendo a radiocirurgia, podem ter influência no resultado final do tratamento. Métodos: série consecutiva de 47 pacientes submetidos à radiocirurgia (1 a 5 sessões), precedida ou não por embolização com cianoacrilato. Acompanhamento clínico e radiológico mínimo de 36 meses. Resultados: a apresentação hemorrágica ocorreu em 68,1% dos pacientes tratados; destes, 62,5% portavam fístula arteriovenosa dentro da malformação arteriovenosa; 83,3% ectasia venosa e 90% restrição à drenagem venosa. A taxa de oclusão de embolização seguida de radiocirurgia foi de 46,1% e da radiocirurgia isolada foi de 52,4% (p=0,671). Foram identificados como fatores favoráveis à oclusão: baixo volume nidal, ausência de fístula arteriovenosa intranidal, maior dose de radiação e baixo grau na classificação das malformações arteriovenosas encefálicas baseadas na radiocirurgia (RBAS). Conclusões: o menor volume nidal (p < 0,001), o menor grau na escala RBAS (p=0,047), a ausência de fístula arteriovenosa intranidal (p=0,001) e a maior dose prescrita (p=0,001) tiveram correlação com resultado favorável no tratamento. Embolização seguida de radiocirurgia não foi superior à radiocirurgia isolada (p=0,772). A eliminação de fístulas arteriovenosas intranidais pela embolização pode aumentar a eficácia da radiocirurgia / Partial nidal embolization preceding radiosurgery of brain arteriovenous malformations (AVM) and some morphological nidal features may be related to final results. Methods: Analysis of a longitudinal cohort of 47 consecutive patients who underwent radiosurgery preceded or not by embolization. Embolizations were performed exclusively with n-butyl cyanoacrylate. Radiosurgery was delivered either as a single or divided up to 5 equal fractions. Clinical and radiological follow up of at least 36 months was obtained. Results: Hemorrhagic presentation was seen in 68.1% of the cases; 62.5% harbored intranidal arteriovenous fistulas (AVF), 83.3% had venous ectasias and 90% had venous outflow stenosis. The occlusion rate of embolization plus radiosurgery was 46.1% and radiosurgery alone was 52.4% (p = 0.671). Variables significantly associated with obliteration were lower nidus volume, lack of intranidal arteriovenous fistula, higher radiosurgical dose and lower grades in radiosurgical-based AVM scale (RBAS). Conclusions: a small nidus (p < 0.001), a lower RBAS grade (p = 0.047), no intranidal AVF (p = 0.001) and greater radiosurgical dose (p = 0.001) were associated to better results. Embolization followed by radiosurgery was not superior to radiosurgery alone (p = 0.772). Endovascular elimination of intranidal AVF\'s may help to promote radiosurgical occlusion

BACKGROUND: Posterior inferior cerebellar artery (PICA) aneurysms are an uncommon, heterogeneous group of aneurysms with poorer neurological outcomes compared to other intracranial aneurysms. At first, as part A, we conducted a systematic review of the literature to evaluate the safety and efficacy of treatment strategies for PICA-aneurysms. Subsequently, as part B, we performed a multicenter retrospective study to analyze the outcome in a large series of patients treated with contemporary microsurgical and endovascular techniques. METHODS: For the meta-analysis, a systematic search of Medline, EMBASE, Scopus and Web of Science was done for studies published through November 2015. We included studies that described treatment of PICA-aneurysms with ≥10 patients. Random-effects meta-analysis was used to pool the following outcomes: complete occlusion, technical success, periprocedural morbidity/mortality, stroke rates, aneurysm recurrence/rebleed, CN-palsies rates, and long-term neurological morbidity/mortality. As the second part, aiming to report the current trends and results in treatment strategies for PICA-aneurysms, records of 94 patients treated for PICA-aneurysms between 2000 and 2015 at 3 large referral neurovascular centers were retrospectively reviewed. RESULTS: In the meta-analysis, we...

1 Abstract Aim: To evaluate the diagnostic performance of FDG PET/CT in the detection of stent graft infection (SGI) with the use of visual and semiquantitative interpretation, to compare it with standalone CT analysis, to verify the transferability of the experience with FDG PET/CT in surgical prosthesis infection and to define the role of the method in the diagnostic algorithm of SGI. Subjects and Methods: In this retrospective study, two nuclear medicine physicians have independently analyzed 21 FDG PET/CT examinations performed in 20 subjects (16 men, 66 ± 8 years) between 2010 and 2019 for clinical suspicion of SGI. Six subjects examined from other reasons without signs of infection constituted a control group. The images were evaluated for the uptake pattern and intensity, and by the maximum standard uptake value (SUVmax), the target-to-background ratio with blood pool (TBRBP) and liver uptake (TBRhep) as a reference. The SGI was defined as the presence of focal hyperactivity with an intensity exceeding hepatic uptake. CT images were independently assessed for signs of SGI. Clinical review of all further patients' data served as the standard of reference. Results: Twelve cases were established as SGI by the clinical review. PET/CT correctly diagnosed SGI in eight and yielded a sensitivity of 92 % and...

BACKGROUND: Posterior inferior cerebellar artery (PICA) aneurysms are an uncommon, heterogeneous group of aneurysms with poorer neurological outcomes compared to other intracranial aneurysms. At first, as part A, we conducted a systematic review of the literature to evaluate the safety and efficacy of treatment strategies for PICA-aneurysms. Subsequently, as part B, we performed a multicenter retrospective study to analyze the outcome in a large series of patients treated with contemporary microsurgical and endovascular techniques. METHODS: For the meta-analysis, a systematic search of Medline, EMBASE, Scopus and Web of Science was done for studies published through November 2015. We included studies that described treatment of PICA-aneurysms with ≥10 patients. Random-effects meta-analysis was used to pool the following outcomes: complete occlusion, technical success, periprocedural morbidity/mortality, stroke rates, aneurysm recurrence/rebleed, CN-palsies rates, and long-term neurological morbidity/mortality. As the second part, aiming to report the current trends and results in treatment strategies for PICA-aneurysms, records of 94 patients treated for PICA-aneurysms between 2000 and 2015 at 3 large referral neurovascular centers were retrospectively reviewed. RESULTS: In the meta-analysis, we...