Modifying flow in the ICA bifurcation: Pipeline deployment from the supraclinoid ICA extending into the M1 segment-clinical and anatomic results.

BACKGROUND AND PURPOSE: Utility of the Pipeline Embolization Device extending to the M1 and its clinical and flow consequences at the ICA bifurcation have not been characterized. We analyzed flow modification in cases where a single Pipeline Embolization Device was deployed from the M1 to the distal supraclinoid ICA, covering the A1, for aneurysm treatment. MATERIALS AND METHODS: A1 flow modifications and size regression in postprocedure and follow-up angiography were analyzed. Vessel diameters and ratios of the proximal A1 and M1 segments and the distal ICA were assessed. Relationships between Pipeline Embolization Device nominal diameter and the vessel diameters at landing zones were obtained. Clinical assessments after flow modification were documented. RESULTS: Six of 7 patients demonstrated no change of flow in the anterior cerebral artery/anterior communicating artery complex at immediate postembolization angiography. All patients who underwent follow-up angiography demonstrated size regression of the ipsilateral A1. Midterm follow-up angiography revealed complete reversal of flow in the ipsilateral A1 in 4 of 5 patients. One patient did not demonstrate flow modification. This patient had a dominant ipsilateral A1. Vessel ratios in this case demonstrated a unique configuration in favor of maintaining patency of the ipsilateral A1. There were no clinical or radiographic signs of ischemia. One patient experienced asymptomatic angiographic in-stent stenosis at the M1. CONCLUSIONS: We found that deployment of a Pipeline Embolization Device from the distal supraclinoid ICA to the M1 may result in reversal of flow in the anterior cerebral artery/anterior communicating artery complex and regression of the ipsilateral A1. Preoperative anatomic quantitation and sizing of the Pipeline Embolization Device may predict flow modification results.

Bowel obstruction in recurrent gynecologic malignancies: defining who will benefit from surgical intervention.

AIM: To define factors that could help select, in a cohort of gynecologic cancer patients with malignant gastro-intestinal obstruction, those most likely to benefit from palliative surgery. METHODS: In this retrospective study of patients with malignant gastro-intestinal obstruction who underwent palliative surgery in our institute over 7 years, outcome measures were oral intake, chemotherapy, and 30-day, 60-day and overall survival. Based on Cox proportional-hazards regression models and Kaplan-Meier curves with log-rank tests, a prognostic score was developed to identify those most likely to benefit from surgery. RESULTS: Sixty-eight palliative surgeries were performed in 62 patients with ovarian (69.1%), primary-peritoneal (8.8%), cervical (11.8%) or uterine (10.3%) malignancies. Procedures were colostomy (26.5%), ileostomy (39.7%), colonic stent (1.5%), gastrostomy (7.3%), gastroenterostomy (5.9%) and bypass/resection and anastomosis (19.1%). Eighteen patients died prior to discharge, within 3-81 days (median 25 days). The 30-day and 60-day mortality rates were 14.7% and 29.4%, respectively. Postoperative oral-intake and chemotherapy rates were 65% and 53%, respectively, with albumin level identified on multivariate analysis as the only significant predictor of both. Median postoperative survival was 106 days (3-1342). Bypass/resection and anastomosis was associated with improved survival. Ascites below 2 L, younger age, ovarian primary tumor, and higher blood albumin correlated with longer postoperative survival. A prognostic index based on these factors was found to identify patients with increased 30-day and 60-day mortality. CONCLUSIONS: Our proposed prognostic index, based on age, primary tumor, albumin and ascites, might help select those gynecological cancer patients most likely to benefit from palliative surgery.

Intradural hemangiopericytoma of the lumbar spine: a rare entity.

We report a case of a patient with an intradural hemangiopericytoma of the lumbar spine and the unusual MR angiography (MRA) and spinal angiography findings of arteriovenous shunting with spinal venous congestion. We highlight the concordance of the unusual MRA and angiographic findings and their relationship to combined endovascular and surgical therapy.

Pseudoaneurysm of the anterior spinal artery in a patient with Moyamoya: an unusual cause of subarachnoid hemorrhage.

Subarachnoid hemorrhage (SAH) is a recognized presentation of Moyamoya disease in adults. Because there are extensive collateral networks and potential complications that develop, a thorough investigation of the intracranial and extracranial circulation is necessary to exclude a treatable cause when these patients present with SAH. We present a case of SAH due to a ruptured pseudoaneurysm of the anterior spinal artery arising from the supreme intercostal artery, which was the sole source of blood supply to the intracranial circulation.

Complications and Their Management During NBCA Embolization of Craniospinal Lesions.

SUMMARY: Technical complications during embolization of craniospinal lesions using NBCA may be classified as nonspecific catheterization-related or specific embolization-related. Catheterization- related complications include vessel injuries such as spasm, dissection or perforation, catheter injuries and thrombus formation. Embolization- related complications include occlusion of normal territories, migration of the embolic material to the venous side, and catheter gluing to the vessel wall. Causes, prevention and management of each complication are discussed with presentation of demonstrative cases.

Bilateral orbital signs predict cortical venous drainage in cavernous sinus dural AVMs.

BACKGROUND: Most cavernous sinus dural arteriovenous malformations (CSdAVM) have a benign clinical course. Those CSdAVM that drain into cortical veins have an increased risk for neurologic complications. OBJECTIVE: To find whether a specific clinical sign predicts cortical venous drainage (CVD) in CSdAVM. METHODS: The records of 118 patients with CSdAVM were evaluated for the clinical features of the disorder and tested for predictive value of CVD demonstrated angiographically or suggested by MRI using logistic regression and odds ratio (OR) analysis. RESULTS: Clinical signs that predicted the presence of CVD included bilateral orbital signs (p = 0.004, OR = 23.84) and presence of a postauricular bruit (p = 0.035, OR = 23.8). No other clinical sign predicted the presence of CVD, including extraocular muscle dysfunction, abducens or oculomotor dysfunction, increased intraocular pressure, venous stasis retinopathy, choroidal effusion, optic neuropathy, subjective bruit, and objective orbital bruit. CONCLUSION: Patients who present with or develop bilateral orbital congestion should be recognized as being at increased risk for CVD.

Surgical management of isolated hemangioblastomas of the spinal cord.

OBJECTIVE: Intramedullary hemangioblastomas are rare tumors, accounting for just 3% of all intraspinal neoplasms. The purpose of this study is to define the occurrence of isolated intramedullary hemangioblastomas and to analyze the role of the radiological studies and surgery for these lesions. METHODS: The charts of 19 consecutive patients operated on for isolated spinal intramedullary hemangioblastoma were reviewed. Preoperatively, all patients underwent magnetic resonance imaging and nine underwent spinal angiography. For all patients, the surgical approach was via posterior laminectomy. RESULTS: Our study sample comprised 6 women and 13 men, with an average age of 31.5 years (range, 16-75 yr). The mean prodrome was 20.8 months. Pain was the most common complaint. In all cases, the neoplasms were associated with a syrinx or edema. Gross total resection was achieved in all patients. At last follow-up examination (mean, 50.1 mo), 13 patients (68%) had improved and 6 patients (32%) had stabilized as compared with their preoperative clinical status. CONCLUSION: Isolated intramedullary hemangioblastomas typically have an indolent clinical course. These tumors have characteristic imaging properties on magnetic resonance imaging and angiography. Surgical removal of these lesions results in excellent long-term functional outcome.

Orbital arteriovenous malformation mimicking cavernous sinus dural arteriovenous malformation.

AIMS: Orbital arteriovenous malformations (OAVM) are rare, mostly described with high flow characteristics. Two cases are reported with an OAVM of distinct haemodynamic abnormality. The clinical, angiographic features, and the management considerations are discussed. METHODS: Case review of two patients with dural AVM (DAVM) who presented to referral neuro-ophthalmology and endovascular services because of clinical symptoms and signs consistent with a cavernous sinus dural AVM. RESULTS: In each patient, superselective angiography revealed a small slow flow intraorbital shunt supplied by the ophthalmic artery. The transarterial and transvenous endovascular approaches to treat the malformation were partially successful. Although, the abnormal flow was reduced, complete closure of the DAVM could not be accomplished without significant risk of iatrogenic injury. Neither patient's vision improved after intervention. CONCLUSION: A DAVM in the orbit can cause similar clinical symptoms and signs to those associated with a cavernous sinus DAVM. Even with high resolution magnetic resonance imaging, only superselective angiography can identify this small intraorbital slow flow shunt. The location in the orbital apex and the small size precludes a surgical option for treatment. The transarterial and transvenous embolisation options are limited.

Visual loss from arterial steal in patients with maxillofacial arteriovenous malformation.

OBJECTIVE: To determine whether an arterial "steal" from the ophthalmic artery accounts for the ocular manifestations associated with maxillofacial arteriovenous malformation (AVM) outside the orbit. DESIGN: Retrospective noncomparative case series. PARTICIPANTS: Seven patients with maxillofacial AVM who had been previously treated, unsuccessfully, with proximal ligation of the supplying external carotid artery branches were evaluated clinically and by superselective cerebral angiography. No cases had intraorbital arteriovenous shunting or abnormal venous drainage to the orbit. INTERVENTION: Endovascular embolization. MAIN OUTCOME MEASURES: Signs and symptoms of ocular ischemia were correlated with findings on cerebral/orbital angiography. RESULTS: Four of seven patients had signs of ocular ischemia. By selective angiography, these four patients were found to have a significant ophthalmic artery supply to the AVM. In contrast, the three patients without signs of ocular ischemia had minimal or no ophthalmic artery supply to the AVM. CONCLUSIONS: When the ophthalmic arterial blood supply is recruited, ophthalmic artery "steal" phenomenon occurs in patients with maxillofacial AVMs that do not directly involve the orbit. This mechanism appears to be the cause of ocular ischemia. It is possible that this "steal" is precipitated or worsened by previous surgical proximal ligation of external carotid arterial branches that are potential collaterals with the ophthalmic artery but fail to occlude the arteriovenous (AV) shunts.

The Accuracy of Plain Skull X-ray Examination as a Predictor of Recanalization Following Guglielmi Detachable Coil Embolisation in the Treatment of Cerebral Aneurysms.

SUMMARY: We evaluated the accuracy of plain skull x-ray series as an imaging modality for the follow-up of cerebral aneurysm recanalization after Guglielmi Detachable Coil (GDC) embolisation. We retrospectively reviewed of 100 consecutive follow-up angiograms and skull x-ray examinations in 78 patients harboring 82 aneurysms and in whom 85 procedures were performed. Angiography was performed between 1 and 54 months (mean: 10.8 months) after embolisation. The skull series (AP, lateral and Towne's projections) were taken at the time of follow-up angiography. Each follow-up angiogram and skull series were compared to the immediate post-coiling, correlating presence or absence of coil compaction on the skull series and recanalization of the aneurysm at angiography. In 97 (97%) examinations, skull x-ray findings correlated with the angiographic findings. In three cases, skull x-ray examination suggested compaction when no recanalization was seen angiographically; in these three cases, the aneurysms were small and found to be more thrombosed than baseline. In no case did angiographic recanalization occur in the absence of compaction on skull series. These findings yield 100% sensitivity, 95% specificity, 93% positive predictive value, 100% negative predictive value and 97% accuracy. The location, size, configuration and neck/dome ratio of the aneurysm were not related to the correlation between angiography and skull x-ray exam. Skull x-ray series is a safe, accurate, and costeffective mode of follow-up for patients with GDC-treated aneurysms. The possibility of it replacing angiography still requires a more comparative skull x-ray modality in follow-up studies.

Symptoms,Vascular anatomy and endovascular treatment of spinal cord arteriovenous malformations.

SUMMARY: The purpose of this study is to evaluate the symptoms, anatomy and efficacy of embolization of spinal cord AVMs (SCAVMs). We performed retrospective analysis of 108 SCAVMs consisting of 38 pediatric and 70 adult cases. They included 81 nidus (26 pediatric) and 27 fistulous (12 pediatric) AVMs. Hemorrhage occurred in 74% of pediatric and 62% of adult cases with multiple hemorrhages in 54% of pediatric and 42% of adult cases. Fistulous AVMs hemorrhaged more frequently in children than adults (75% vs. 13%). 75 cases were treated with embolization alone, 10 with surgery and embolization , 2 with embolization following radiation and 12 with surgery alone. 9 patients received no treatment. In 79 of 87 embolized patients, acrylic was utilized either alone (49) or in combination (30) with other materials. Embolization was attempted 156 times in 93 patients. Complete obliteration by embolization was obtained in 17 cases. If complete obliteration was not possible, partial targeted embolization was performed, aiming at dangerous anatomic structures such as aneurysms. During the follow-up period (mean: 34 months), hemorrhage was observed in only 2 cases. Although technical complications such as dissection or vasospasm occurred on 19 occasions, only 4 resulted in aggravation of neurological symptoms. Of the 21 sessions in which worsening of symptoms occurred after embolization, 10 resulted in permanent deficits and eight of these occurred prior to 1990. SCAVMs have a poor functional prognosis due to frequent hemorrhage if untreated. Embolization with acrylic is feasible as the first choice of treatment. Provocative test and electrophysiological monitoring have improved safety. Partial targeted embolization is effective in preventing hemorrhage.

Venous anomalies and associated lesions.

Developmental venous anomalies (DVAs) of the central nervous system are an exaggeration of the normal venous collector system, not a vascular lesion. They may be associated with many vascular and nonvascular processes with the nervous system including tumors, demyelinating lesions, arteriovenous malformations (AVMs), dural AVMs, cavernous malformations, and vascular lesions of the head, face, and eye. The instigating factors involved are not completely understood. The primary clinical significance of DVAs is that planned or inadvertent occlusion during treatment of associated lesions frequently leads to venous infarction of the surrounding normal brain.

Spinal dural arteriovenous fistulae draining to the anterior spinal vein: angiographic diagnosis.

OBJECTIVE: To describe and present atypical spinal dural arteriovenous fistulae (SDAVFs) that drain into the anterior spinal vein (ASV) and thus cause some degree of difficulty in differentiating the anterior spinal artery from the ASV. METHODS: A retrospective review of 80 selective spinal angiography procedures (with or without endovascular treatment) performed on SDAVFs since 1980 identified three cases in which the venous drainage was into a dilated ASV via a radicular vein. The patients included two men and one woman, ranging in age from 55 to 82 years (mean age, 71 yr), all of whom presented with mild to severe progressive paraparesis and sensory disturbance. RESULTS: The appearance of the venous drainage mimicked that of the usual hairpin configuration of the radiculomedullary artery and therefore caused diagnostic difficulty. There are no characteristic clinical features that differentiate this form of SDAVF from the usual type of SDAVF. The angiographic criteria for identification of the ASV draining an SDAVF include the demonstration of the branching of the ASV and its drainage into the epidural vein, opacification of other medullary veins connected with the ASV, recognition of distortion of the hairpin shape, and the identification of the anterior spinal artery at the segment where the ASV is opacified. Two patients were treated with embolization and one with surgery. All patients improved after the treatment. CONCLUSION: Before performing endovascular treatment, thorough spinal angiography with an appropriate field of view must be performed to identify this unusual type of SDAVF.

Visual symptoms with dural arteriovenous malformations draining into occipital veins.

OBJECTIVE: To determine the cause of the visual dysfunction and effect of treatment on dural arteriovenous malformations (DAVMs) that secondarily involve the occipital lobe. BACKGROUND: DAVMs are an infrequent cause of visual dysfunction that should be amenable to treatment if diagnosed before permanent visual field loss. METHODS: The records of seven patients with cerebral visual disturbances associated with DAVMs were analyzed with attention to visual symptoms, visual field testing, and vascular anatomy. RESULTS: Sudden visual loss occurred in five patients, two with a hemorrhage and one with a venous infarct in the occipital lobe. Fortification images occurred in three patients, two of whom had palinopsia (one with de novo formed visual hallucinations). Homonymous quadrantic or hemianoptic field defects, some fluctuating, were found in six patients. Angiography revealed each DAVM was supplied solely by dural arteries and drained into occipital pial veins due to retrograde blood flow through the sites near or in the wall or lumen of the dural venous channels that normally drain the occipital lobe. Unlike DAVMs in other locations, only two patients had occlusion of an adjacent venous sinus. These patients, particularly the two with posterior fossa DAVMs remote to the occipital lobe, clearly demonstrate the visual and neurologic dysfunction resulting from venous hypertension. In six patients, intra-arterial embolization of the arterial feeders and nidus (one patient required additional surgery) resulted in resumption of normal occipital venous emptying. No further visual episodes occurred in five of these six patients. The visual fields normalized in three patients and improved in one with venous infarct but were unchanged in both patients with a hemorrhage. CONCLUSIONS: DAVMs that drain into occipital veins cause field loss and other visual disturbances because of venous hypertension in the occipital lobe, which can be reversed by occluding the DAVM nidus. If a venous infarct or hemorrhage has not caused irreversible damage, visual recovery should be complete.

Shedding kinetics of soluble tumor necrosis factor (TNF) receptors after systemic TNF leaking during isolated limb perfusion. Relevance to the pathophysiology of septic shock.

We examined the kinetics of shedding of the soluble TNF receptors (TNF-Rs) in response to TNF leakage during isolated limb perfusion procedures and correlated them to the resulting hemodynamic effects. Shedding of the TNF-Rs started 7 min after TNF leakage into the systemic circulation. Three waves of shedding were observed peaking at 1, 8-12, and 48-72 h both in vivo and in cell cultures. The soluble receptors prolonged the half-life of TNF in the systemic circulation to 2.5-6 h. Excess shedding of the p75 compared with p55 TNF-Rs was noted during the first wave. The amount and speed of shedding of the p75 TNF-Rs were proportional to the serum TNF levels (P < 0.001). A maximal shedding capacity was attained only during the first wave of shedding, at TNF concentrations of approximately 1.5 ng/ml. Above this level, the linearity between TNF and its soluble receptors was lost. TNF-induced hypotension coincided with the initial imbalance between the concentrations of TNF and its soluble receptors. Despite the spontaneous correction of this imbalance at 8-12 h, the hemodynamic and biochemical alterations persisted and were further aggravated at 18 h, suggesting that other factors induced earlier by TNF are responsible for the perpetuation of the hemodynamic instability. This study may provide the basis for a more physiological therapeutic approach to TNF neutralization in septic shock patients.

Motor evoked potentials predicting early recovery from paraparesis after embolisation of a spinal dural arteriovenous fistula.

SUMMARY: Spinal dural arteriovenous malformation is an increasingly diagnosed cause of ischaemic myelopathy. Though routine intraoperative monitoring has been demonstrated to be of benefit in the endovascular treatment of these lesions, its predictive value has not been well documented. We present the case of an elderly woman with progressive spastic paraparesis who demonstrated marked improvement in limb muscle motor evoked potentials of the lower extremities immediately following endovascular occlusion of the lesion. The patient subsequently showed improvement in strength, sensation and sphincter control.

Transumbilical catheterization of cerebral arteries.

OBJECTIVE AND IMPORTANCE: For neonates requiring cerebral endovascular procedures, an alternative route of arterial access, the umbilical artery, is described. Transfemoral catheterization, with its attendant risks, can thus be avoided. CLINICAL PRESENTATION: Six neonates with severe cardiac failure secondary to aneurysmal malformations of the vein of Galen underwent transarterial embolization in an effort to reduce flow through the intracranial arteriovenous malformations and therefore improve control of the high output cardiac failure. TECHNIQUE: The transumbilical route was used in each case, with successful devascularization of some of the malformations in all patients. The femoral arteries were preserved for future staged embolizations. No complications related to the umbilical artery catheterization were encountered. CONCLUSION: Femoral artery cannulation in neonates is technically challenging and may result in stenosis or thrombosis of the vessel. The umbilical artery provides an alternative route of vascular access for cerebral artery catheterization and embolization in these patients, preserving the femoral arteries for future interventions.

Embolization of spinal dural arteriovenous fistulae: results and follow-up.

OBJECTIVE: To evaluate the efficacy of embolization for spinal dural arteriovenous fistulae (SDAVF). METHODS: We reviewed 49 cases of SDAVF treated by embolization. An acrylic material was used in all except two cases. Variable stiffness microcatheters were used in 38 cases. RESULTS: "Adequate" initial treatment was performed in 39 cases (80%). After the introduction of variable stiffness microcatheters, the initial success rate of embolization increased to 87% (33 of 38 cases). Eight patients underwent subsequent embolization for recurrence after "adequate" embolization. Causes of recurrence were collateralization in five cases, development of new fistulae in one, and unknown in two. Two additional patients developed subsequent aggravation of the symptoms, probably caused by progressive venous thrombosis, that responded to heparinization. Ten cases were initially "inadequately" embolized. Five of the 10 cases were treated before the introduction of variable stiffness microcatheters. Each of three of the remaining five cases had a common trunk from which the feeder and a spinal cord artery arose. CONCLUSION: Embolization with an acrylic material should be the first choice of treatment for SDAVF, unless a spinal cord artery shares the same pedicle as the feeder of SDAVF. Subsequent aggravation of the symptoms after embolization can occur by various mechanisms. Therefore, periodic and long-term follow-up examinations are important.

Vertebrospinal angiography in the evaluation of vertebral and spinal cord disease.

Spinal angiography is an infrequently performed radiologic procedure requiring much skill and knowledge for its proper application. Most commonly, spinal angiography is used in the diagnosis of spinal arteriovenous malformations and in the delineation of vascular tumors of the spinal cord. Less usual indications may include preoperative evaluation of the spinal cord vasculature prior to surgeries involving the descending thoracic aorta or ventrolateral approaches to the spine, particularly in patients undergoing repeat operations. Spinal angiography should address three crucial considerations for the surgeon or neurointerventionalist: (1) the exact location and anatomic configuration of the lesion, (2) the vascularity of a lesion and identification of all feeding and draining vessels, and (3) depiction of the regional vascular anatomy of the spinal cord in relation to the lesion. Considering the relatively longer length of the procedure, larger contrast volumes, and increased complexity (as measured by catheter exchanges required) of spinal angiography, however, certain angiographic techniques (e.g., digital subtraction angiography, the use of general anesthesia, or placement of a groin sheath to facilitate catheter exchanges) and the use of low osmolality contrast agents should be considered to improve the quality of the examination while reducing risk.

Angiography of cerebral aneurysms.

Magnetic resonance and computed tomographic angiography have been increasingly applied to the study of disease affecting the cerebral vasculature. Despite these advances, however, conventional cerebral angiography clearly remains the diagnostic gold standard and essential guide to any microneurosurgical or endovascular therapeutic decision concerning cerebral aneurysms. Detailed cerebral angiography is a dynamic study and is influenced by prior axial imaging. It should be tailored to the specific circumstance to obtain information required for selection of the most beneficial treatment.