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Joachim M Gilsbach

Publications and source records attributed to Joachim M Gilsbach.

At least 19 recordsLinked to original sources
PubMed2006

Low-dose aspirin before spinal surgery: results of a survey among neurosurgeons in Germany.

The main problem faced by the increasing numbers of patients presenting for spinal surgery are receiving concurrent medication with low-dose aspirin, leading to dysfunctional circulating platelets. The contribution of low-dose aspirin to increased peri-operative risk of bleeding and blood loss is a contentious issue with conflicting published results from different surgical groups. Data from neurosurgical spine patients is sparse, but aspirin has been identified as an important risk factor in the development of post-operative hematoma following intracranial surgery. We surveyed the opinions and working practices of the neurosurgical facilities performing spinal operations in Germany regarding patients who present for elective spinal surgery. Identical questionnaires were sent to 210 neurosurgical facilities and proffered five main questions: (1) the adherence of any policy of stopping aspirin pre-operatively, (2) the personal risk assessment for patients with spinal surgery under low-dose aspirin medication, (3) the preferred method of treatment for excessive bleeding in this context, (4) personal knowledge of hemorrhagic complications in this group of patients, and (5) the characteristics of the neurosurgical units concerned. There were 145 (69.1%) responses of which 142 (67.6%) were valid. Of the respondents, 114 (80.3%) had a (written) departmental policy for the discontinuation of pre-operative aspirin treatment, 28 (19.7%) were unaware of such a policy. The mean time suggested for discontinuation of aspirin pre-operatively was 6.9 days (range: 0-21 days), with seven respondents who perform the operations despite the ongoing aspirin medication. Ninety-four respondents (66.2%) considered that patients taking low-dose aspirin were at increased risk for excessive peri-operative hemorrhage or were indetermined (8.6%), and 73 (51.4%) reported having personal experience of such problems. Ninety-two respondents (65.5%) would use special medical therapy, preferably Desmopressin alone or in combination with other blood products or prohemostatic agents (46.1%), if hemorrhagic complications developed intra- or post-operatively. The average number of spinal operations per year in each service was 607.9 (range: 40-1,500). Despite the existence of distinct departmental policies concerning the discontinuation of low-dose aspirin pre-operatively in the majority of neurosurgical facilities performing spinal operations, there is a wide range of the moment of this interruption with an average of 7 days. Two-thirds of the respondents felt that aspirin was a risk factor for hemorrhagic complications associated with spinal procedures, and more than half of the interviewees reported having personal experience of such problems. Finally, various medicamentous methods of counteracting aspirin-induced platelet dysfunction and excessive bleeding in this context are elicited, discussed and evaluated.

Aspirin↗
PubMed2006

Pathogenesis, diagnosis and management of pneumorrhachis.

Pneumorrhachis (PR), the presence of intraspinal air, is an exceptional but eminent radiographic finding, accompanied by different aetiologies and possible pathways of air entry into the spinal canal. By reviewing the literature and analysing a personal case of traumatic cervical PR after head injury, we present current data regarding the pathoanatomy, clinical and radiological presentation, diagnosis and differential diagnosis and treatment modalities of patients with PR and associated pathologies to highlight this uncommon phenomenon and outline aetiology-based guidelines for the practical management of PR. Air within the spinal canal can be divided into primary and secondary PR, descriptively classified into extra- or intradural PR and aetiologically subsumed into iatrogenic, traumatic and nontraumatic PR. Intraspinal air is usually found isolated not only in the cervical, thoracic and, less frequently, the lumbosacral regions but can also be located in the entire spinal canal. PR is almost exceptional associated with further air distributions in the body. The pathogenesis and aetiologies of PR are multifold and can be a diagnostic challenge. The diagnostic procedure should include spinal CT, the imaging tool of choice. PR has to be differentiated from free intraspinal gas collections and the coexistence of air and gas within the spinal canal has to be considered differential diagnostically. PR usually represents an asymptomatic epiphenomenon but can also be symptomatic by itself as well as by its underlying pathology. The latter, although often severe, might be concealed and has to be examined carefully to enable adequate patient treatment. The management of PR has to be individualized and frequently requires a multidisciplinary regime.

Craniocerebral Trauma↗
PubMed2006

Posterior foraminotomy or anterior discectomy with polymethyl methacrylate interbody stabilization for cervical soft disc disease: results in 292 patients with monoradiculopathy.

STUDY DESIGN: Retrospective study of patients who underwent either ventral microdiscectomy and polymethyl methacrylate (PMMA) interbody stabilization or posterior foraminotomy for the treatment of cervical monoradiculopathy caused by soft disc disease. OBJECTIVES: To evaluate the long-term outcome after 2 different surgical procedures in the treatment of cervical radiculopathy, compare them with each other and with previous data from other surgical techniques, and outline the indications, advantages, and disadvantages of each procedure. SUMMARY OF BACKGROUND DATA: Cervical disc disease can lead to morphologic different disc lesions, which again may differ in clinical presentation, operative treatment, and outcome. This study provides a clinical long-term follow-up of ventral and dorsal approaches. METHODS: Follow-up evaluation (mean 72.1 +/- 25.9 months) after surgery of monoradicular symptoms was performed in 292 patients. Patients with hard disc disease, myelopathy, neoplasms, or traumatic or recurrent cervical disc disease were excluded. A total of 124 patients (42.5%) underwent ventral microdiscectomy and PMMA stabilization (group A), and in 168 patients (57.5%), a posterior foraminotomy was performed (group B). The outcome was determined according to Odom criteria based on a questionnaire or a telephone interview and was related to the following variables: morphologic findings, neurologic findings, duration of symptoms, operation technique applied, age, sex, and cervical level involved. RESULTS: The success rate (Odom I + II) without consideration of morphologic findings was higher after anterior microdiscectomy with PMMA stabilization (93.6%) than after posterior foraminotomy (85.1%) (P < 0.05). The success rate was higher in cases with pure soft discs in both groups (A: 96.6%; B: 85.8%) than in cases with a mixture of soft and hard discs (A: 90.6%; B: 80%), without gaining statistical significance. Complications related to surgery occurred in 6.5% (group A) and 1.8% (group B) of patients (P < 0.05). CONCLUSION: The findings show that apparently a higher success rate results after anterior microdiscectomy with PMMA interbody stabilization for treatment of degenerative cervical monoradiculopathy than after posterior foraminotomy. Considering the type of morphology of the pathology that causes the radiculopathy, pure soft discs have a better outcome than mixtures of soft and hard discs, independent of the chosen approach. Although statistically significant differences in clinical data were found in both groups, both approaches seem to have equivalent value in individual indications.

Adult↗
PubMed2006

Lumbar foraminal and far lateral juxtafacet cyst of intraspinal origin.

BACKGROUND: Symptomatic lumbar juxtafacet cysts (JFC) arise from the facet joint and almost exclusively are located in the posterolateral spinal canal. A foraminal and far lateral JFC of intraspinal origin is an exceptional finding. We report the unique case of a lumbar intra-, trans-, and extraforaminal JFC to illustrate the rare location and unusual presentation and discuss its anatomical variants, diagnostic difficulties, and therapeutic consequences. CASE DESCRIPTION: A patient presented with a left L3 radiculopathy. Computed tomography revealed an intraspinal cystic posterolateral mass at level L3-L4, accompanied by an intra- and extraforaminal lesion compressing the upper nerve root. Based on these findings, a JFC and an additional extraforaminal disc herniation were suspected. Magnetic resonance imaging showed that the intraforaminal and extraspinal mass communicated with the intraspinal lesion and was cystic as well. The patient was treated successfully by combining an interlaminar and paraisthmic access. Microsurgery disclosed a JFC, which had a small intraspinal, panforaminal, and large extraspinal part. CONCLUSION: An unusual case of a JFC originating intraspinally and extending through the neuroforamen to become a symptomatic extraspinal lesion with compression of the upper nerve root is reported. The patient's excellent response to operative treatment confirmed the effectiveness of the combined microsurgical approach applied. The occurrence of JFC should be kept in mind in differential diagnosis of both intra- and extraspinal and foraminal lumbar lesions.

Female↗
PubMed2006

Long-term histological and scanning electron microscopy results of endovascular and operative treatments of experimentally induced aneurysms in the rabbit.

OBJECTIVE: Treatment strategies of cerebral aneurysms include surgical clipping and endovascular therapies. To determine the long-term results of these therapeutic strategies, the vessel wall reaction close to the former aneurysm was studied according to the assumption that an intact endothelial layer over the former aneurysm neck constitutes complete vessel wall reconstruction and stable aneurysm obliteration. METHODS: Aneurysms were created in 40 rabbits by intraluminal elastase incubation of the common carotid artery. Five animals each were assigned to the following groups: untreated, porous stents, polyurethane covered stentgrafts, porous stents with subsequent coiling. Ten animals were treated with coils alone, 10 with clips. After 6 months, angiography, histology, and scanning electron microscopy was performed. RESULTS: Porous stents did not obliterate the aneurysm, whereas stentgrafts did; in-stent stenosis of up to 60% was present because of neointimal multilayer proliferation. After coiling, the aneurysm dome was occluded with fibrinous and collagenous material, whereas the aneurysm neck was not covered by an endothelial lining. Coil loops lay bare within the vessel, with fresh thrombus material on their surface. After clipping, a thin layer of endothelial lining bridging the two attached vessel walls was present, thereby completely obliterating the aneurysm and reconstructing the vessel wall. CONCLUSION: This study demonstrates complete and stable aneurysm obliteration with vessel wall reconstruction after clipping, a sufficient obliteration of the aneurysm dome using endovascular techniques, but a failed healing response of the aneurysm neck that might correlate to its associated higher risk of rebleed. Whether or not this is counterbalanced by the better immediate outcome after endovascular treatment remains a matter of debate.

Animals↗
PubMed2005

White matter fiber tracts of the human brain: three-dimensional mapping at microscopic resolution, topography and intersubject variability.

The position and extent of individual fiber tracts within the white matter of human brains can be identified in vivo using diffusion tensor imaging (DTI) and fiber tracking methods. Previous to this study, however, the lack of three-dimensional (3-D) probability maps precluded comparing the anatomical precision of MRI studies with microscopically defined fiber tracts in human postmortem brains. The present study provides 3-D registered maps of the topography, course and intersubject variability of major fiber tracts, which were identified at microscopic resolution. The analyzed tracts include the corticospinal tract, optic and acoustic radiations, fornix, cingulum, corpus callosum, superior longitudinal, superior and inferior occipito-frontal and uncinate fascicles; sources and targets of fiber tracts include the lateral and medial geniculate nuclei and mamillary bodies. Tracts and nuclei were identified in serial myelin-stained histological sections of ten postmortem brains. The sections were 3-D reconstructed and registered to a standardized stereotaxic space of an in vivo MR reference brain by means of linear and non-linear, elastic transformations. The individual fiber tracts and nuclei were superimposed in the reference space, and probability maps were generated as a quantitative measure of intersubject variability for each voxel of the stereotaxic space. This study presents the first stereotaxic atlas of the course, location and extent of fiber tracts and related nuclei based on microscopically defined localization and topographic data taken at multiple levels on each of the three orthogonal planes. The maps are useful for evaluating and identifying fiber bundles in DTI, for localizing subcortical lesions visible in anatomical MR images and for studying neuronal connectivity.

Adult↗
PubMed2005

Prospective demonstration of short-term motor plasticity following acquired central pareses.

The effect of newly acquired central pareses on functional MRI (fMRI) signal pattern is not known, since up to now all investigated patients were examined while they already experienced the motor weakness. We describe the first prospective and controlled study demonstrating the impact of new, acquired central pareses on fMRI motor activation pattern. Six patients suffering from a new central paresis after resection of a brain tumor infiltrating the central region were prospectively compared with a control group of five patients without postoperative paresis and a group of six healthy, age-matched controls who were investigated at two time points. fMRI signal was postoperatively analyzed during the performance of hand motor tasks and compared to the preoperative fMRI results. The relative signal change between rest and activation was evaluated for five cortical regions: the primary motor cortex (M1) and the ipsilateral primary motor cortex (M1i), the supplementary motor area (SMA), the premotor area (PMA), and the superior parietal lobule (SPL). In the patients with new postoperative central pareses, significant (P = 0.0313) decreases in fMRI activation were found in M1, whereas significant (P = 0.0313) increases were found in SMA and PMA. For M1i and SPL, there was a signal increase on average as well, but it failed to reach significance (P = 0.1250). In both control groups, no significant changes between both examinations were seen. Even though the number of investigated patients is too small to draw definite conclusions, our results support the concept of short-term motor plasticity being mediated by redundant systems that may take over function after damage of the primary motor cortex. The findings potentially also reflect increased functional demands imposed upon the motor network subsequent to a loss of dexterity.

Adult↗
PubMed2005

Minor inflammation after surgical evacuation compared with fibrinolytic therapy of experimental intracerebral hemorrhages.

OBJECTIVES: Toxic components released from the intracerebral blood clot, such as thrombin and hemoglobin, potentially trigger brain edema formation and therefore favor an early evacuation of the clot. Despite a significant reduction in hematoma size in our porcine model of hematoma induction by injecting autologous blood ICP-controlled into the right frontal white matter with subsequent fibrinolysis using recombinant tissue-plasminogen activator (rt-PA) and aspiration of the liquefied clot (n = 9), local rt-PA promoted delayed perihematomatous edema formation and invoked a substantial inflammatory reaction compared with controls (n = 11). METHODS: We therefore modified our formerly developed porcine model of intracerebral hemorrhage in removing the hematoma by open craniotomy and suction of the clot in seven animals. The residual hematoma size and extent of perifocal edema were evaluated over 10 days on planimetry of the MRI data, and correlated to the histopathological changes of edema and inflammation found at autopsy. RESULTS: The edema volume on day 4 was significantly less in the surgical group compared with the lysis group (p < 0.03). On day 10, however, the difference in edema size was not statistically significant compared with the lysis group (p < 0.07) and the control group (p < 0.09). The inflammatory response was minor compared with the lysis and control group. DISCUSSION: In conclusion, despite a significant reduction in hematoma size by surgical removal of the clot, only the inflammatory response, but not the extent of delayed edema can be positively influenced.

Analysis of Variance↗
PubMed2005

Sequential visualization of brain and fiber tract deformation during intracranial surgery with three-dimensional ultrasound: an approach to evaluate the effect of brain shift.

OBJECTIVE: We present a technique that allows intraoperative display of brain shift and its effects on fiber tracts. METHODS: Three patients had intracranial lesions (one malignant glioma, one metastasis, and one cavernoma) in contact with either the corticospinal or the geniculostriate tract that were removed microneurosurgically. Preoperatively, magnetic resonance diffusion-weighted imaging (DWI) was performed to visualize the fiber tract at risk. DWI data were fused with those obtained from anatomic T1-weighted magnetic resonance imaging. A single-rack three-dimensional ultrasound neuronavigation system, which simultaneously displays the MRI scan and the corresponding ultrasound image, was used intraoperatively for 1) navigation; 2) definition of fixed and potentially shifting ultrasound landmarks near the fiber tract; and 3) sequential image updating at different steps of resection. The result was time-dependent brain deformation data. With a standard personal computer equipped with standard image software, the brain shift-associated fiber tract deformation was assessed by use of sequential landmark registration. After surgery, DWI was performed to confirm the predicted fiber tract deformation. RESULTS: The lesions were removed without morbidity. Comparison of three-dimensional ultrasound with DWI and T1-weighted magnetic resonance imaging data allowed us to define fixed and potentially shifting landmarks close to the respective fiber tract. Postoperative DWI confirmed that the actual fiber tract position at the conclusion of surgery corresponded to the sonographically predicted fiber tract position. CONCLUSION: By definition and sequential intraoperative registration of ultrasound landmarks near the fiber tract, brain shift-associated deformation of a tract that is not visible sonographically can be assessed correctly. This approach seems to help identify and avoid eloquent brain areas during intracranial surgery.

Adolescent↗
PubMed2005

Gamma knife surgery for atypical meningiomas.

OBJECT: Complete resection is the optimal treatment for atypical meningiomas (AMs) but its feasibility depends on the tumor site. The object of this study was to assess the effect of gamma knife surgery (GKS) on AM. METHODS: In 15 patients 21 AMs were treated by GKS. Four patients had residual lesions and 10 patients had recurrent tumors after one or more microsurgical interventions. Three patients were treated twice with GKS because of tumor tissue outside the treatment volume, either at the margin or at a distant location. The median clinical and neuroimaging follow-up period was 35 months (range 21-67 months). Ten tumors shrank 6 to 12 months after GKS, 10 remained stable, and one grew. Between 18 and 36 months after GKS, four patients had a distant recurrence, and two had a margin recurrence. In one of these cases, an additional local recurrence was demonstrated 1 year later, and the patient underwent standard radiotherapy. No patient suffered persistent adverse effects after radiosurgery. CONCLUSIONS: After early tumor shrinkage, high recurrence rates were demonstrated both at the treatment margin and at distant locations in cases treated for AM. There was only one recurrence within the GKS radiation field. For small- and medium-sized AMs GKS may be a safe adjunct to other treatment modalities.

Adult↗
PubMed2005

Functional outcome after surgical treatment of spontaneous and nonspontaneous spinal subdural hematomas.

OBJECT: Because of the rarity of spinal subdural hematomas (SDHs), the literature offers scarce estimates of the outcome and predictive factors in patients suffering from these lesions. In addition, single-institution surgical series are still lacking. Therefore, the authors retrospectively evaluated the early and long-term functional outcomes measured in eight patients with spontaneous and nonspontaneous spinal SDHs in whom the clot had been evacuated. METHODS: The patients' charts were evaluated for origin of the lesion, risk factors, and neurological deficits at symptom onset and at 28 days after extirpation of the spinal SDH. Long-term clinical outcome (Barthel Index [BI]) was evaluated by administering a telephone questionnaire to the patient or a relative. Only one patient with a spontaneous spinal SDH was identified. Four patients were undergoing anticoagulant therapy, and three patients had undergone a previous anesthetic/diagnostic spinal procedure. Twenty-eight days postoperatively, neurological deficits improved in six of eight patients; however, in two of the six patients, the improvement did not allow the patients to become independent again. In two patients, surgery did not affect the complete sensorimotor deficits. In the long-term survivors (median 45 months) a median BI of 55 was achieved. The latency between symptom onset and surgery did not correlate with functional outcome in this series. The preoperative neurological condition and location of the hematoma correlated positively with early and long-term functional outcome. CONCLUSIONS: To the best of their knowledge, the present study is the largest single-institutional study of patients with surgically treated spinal SDHs. Despite some postoperative improvement of sensorimotor deficits in most patients, the prognosis is poor because 50% of the patients remain dependent. Their outcome was determined by the preoperative sensorimotor function and spinal level of the spinal SDH.

Adult↗
PubMed2004

Spinal vascular malformations.

Spinal vascular malformations are rare diseases that consist of true inborn cavernomas and arteriovenous malformations (including perimedullary fistulae, glomerular and juvenile AVMs) and presumably acquired dural arteriovenous fistulae. This review article gives an overview of the imaging features both on MRI and angiography, the differential diagnoses, the clinical symptomatology and the potential therapeutic approaches to these diseases. It is concluded that MRI is the diagnostic modality of first choice in suspected spinal vascular malformation and should be complemented by selective spinal angiography. Treatment in symptomatic patients offers an improvement in the prognosis, but should be performed in specialized centers. Patients with spinal cord cavernomas and perimedullary fistulae type I are surgical candidates. Dural arteriovenous fistulae can either be operated upon or can be treated by an endovascular approach, the former being a simple, quick and secure approach to obliterate the fistula, while the latter is technically demanding. In spinal arteriovenous malformations, the endovascular approach is the method of first choice; in selected cases, a combined therapy might be sensible.

Angiography↗
PubMed2004

Frame-based and frameless stereotactic hematoma puncture and subsequent fibrinolytic therapy for the treatment of spontaneous intracerebral hemorrhage.

OBJECTIVES: Comparison of two minimally invasive procedures for the treatment of intracerebral hemorrhage and subsequent lysis with regard to technical implications and clinical outcome of the patients. METHODS: Retrospective analysis of 126 patients with spontaneous supratentorial intracerebral hemorrhage treated by frame-based (n=53) or frameless (n=75) hematoma aspiration and subsequent fibrinolysis with recombinant tissue plasminogen activator (rt-PA). Data were analysed for the whole group as well as for the two subsets of patients with regard to hematoma reduction, procedure-related complications, and the early and long term clinical outcome of the patients. Functional outcome was rated using the Glasgow Outcome Scale (GOS) and Barthel-Index (median follow-up 178 weeks). The prognostic impact of patient related covariates on the GOS was analysed using logistic regression analysis. RESULTS: 49 out of 126 patients (38.9 %) died, 25 of them in the early postoperative period. Only 22/126 (17.5 %) had a favorable long term outcome (GOS >3). Age > 65 years was significantly (p<0.03, OR 3.6) associated with a higher risk for an unfavorable long term outcome (GOS < or = 3). Treatment had no impact on outcome. Both techniques were highly effective in reducing the intracerebral blood volume by 75.8+/-21.4% of the initial hematoma volume in frame-based and 64.8+/-25.4 % in frameless stereotaxy within 2 days of rt-PA-therapy. Malpositioning of the catheter occurred more often in the frameless group (21.3% vs. 9.4 % in the frame-based procedure) without gaining statistical significance. CONCLUSIONS: Frame-based and frameless stereotactic hematoma aspirations with subsequent fibrinolysis are effective in volume reduction of intracerebral hemorrhage with comparable clinical outcome. The frameless procedure is associated with a higher risk for malpositioning of the catheter. Despite effective hematoma reduction with both techniques, the percentage of patients with a good clinical outcome remained limited especially in the elder subpopulation.

Aged↗
PubMed2004

Preoperative mapping of cortical motor function: prospective comparison of functional magnetic resonance imaging and [15O]-H2O-positron emission tomography in the same co-ordinate system.

BACKGROUND: Two of the most widely accepted approaches to map eloquent cortical areas preoperatively are positron emission tomography (PET) and functional magnetic resonance imaging (fMRI). As yet, no study has compared these two modalities within the same frame of reference in tumour patients. AIM: We employed [15O]-H2O-PET and fMRI in patients undergoing presurgical evaluation and compared the results with those obtained by direct electrical cortical stimulation (DECS). METHODS: Twenty-five patients with tumours of different aetiology near the central region were investigated. fMRI and PET were processed using the same methods, i.e. statistical parametric mapping (SPM) without anatomical normalization, and transformed into the same frame of reference. RESULTS: fMRI activity was found in more cranial and lateral sections, i.e. closer to the brain surface, in comparison with PET, which demonstrated parenchymal activation. The mean localization difference between fMRI and PET was 8.1 +/- 4.6 mm (range, 2-18 mm). fMRI and [15O]-H2O-PET could reliably identify the central sulcus, as demonstrated by DECS. CONCLUSIONS: fMRI and [15O]-H2O-PET demonstrate comparable results and are sensitive and reliable tools to map the central region, especially in cases of infiltrating brain tumours. However, fMRI is more prone to artefacts, such as the visualization of draining veins, which may explain the more cranial and lateral activation visualized by fMRI, whereas PET depicts capillary perfusion changes and therefore shows activation closer to the parenchyma.

Adult↗
PubMed2004

Prevalence of pituitary deficiency in patients after aneurysmal subarachnoid hemorrhage.

After aneurysmal subarachnoid hemorrhage (SAH), patients frequently present with persistent bodily, psychosocial, and cognitive impairments that resemble those of patients with untreated partial or complete pituitary insufficiency. Because of these similarities, the authors hypothesized that aneurysmal SAH may cause pituitary dysfunction. Pituitary function testing was performed in 40 aneurysmal SAH patients between 12 and 72 months after the SAH. A combined TRH-LHRH-arginine test and the insulin tolerance test were performed on two separate days. Only 18 of 40 (45%) of the tested patients had normal pituitary function. Five of 40 exhibited isolated severe GH deficiency (GHD), and an additional three of 40 had severe GHD plus corticotroph deficiency. Isolated corticotroph deficiency was seen in 13 of 40 patients, and one patient showed isolated thyrotroph deficiency. All but one patient with corticotroph insufficiency were female. Patients with severe GHD had gained significantly more weight since their SAH than patients without GHD and exhibited a significantly higher body mass index. None of the clinical parameters indicative of a poor neurological outcome in aneurysmal SAH were related to pituitary insufficiency. In summary, neuroendocrine dysfunction was identified in a substantial portion of patients with previous aneurysmal SAH and should be borne in mind as a potential long-term sequel of the illness.

Adrenal Glands↗
PubMed2003

A refined method for creating saccular aneurysms in the rabbit.

We describe a refined animal model of human intracerebral aneurysms for testing endovascular devices for interventional neuroradiological procedures. Saccular aneurysms resulting from a stump of the right common carotid artery (CCA) were created in 15 New Zealand White rabbits by intraluminal incubation of elastase that was applied to the CCA after distal ligation of the CCA and proximal occlusion of the vessel using a pliable balloon. Subsequently a microcatheter was advanced to a position cranial to the balloon and the elastase was infused under fluoroscopic guidance to avoid retrograde flow to the trachea via aberrant vessels. Contrast-enhanced (CE) MRA at 1.5 T and conventional digital subtraction angiography was performed to test for aneurysm size, morphology and neck anatomy. In all 15 animals aneurysms resulted from the stump of the right CCA, ranging in size from 2.0 to 9.9 mm (mean 6.3 mm) in craniocaudal direction, 1.0 to 5.5 mm (mean 3.8 mm) in mediolateral direction and 1.0 to 3.8 mm (mean 2.4 mm) in neck diameter. Aneurysm morphology could be adequately demonstrated using CE MRA. On histological evaluation a loss of the internal elastic lamina was noted. The described method represents an easy, reliable, and reproducible method of aneurysm creation in the rabbit in an area of high shear stress. These aneurysms can be used for testing new endovascular devices for embolization of intracranial aneurysms.

Angiography, Digital Subtraction↗