[Current controversies in the diagnosis and management of cerebral venous and dural sinus thrombosis]

Over the last few years, the results from clinical studies and innovative radiological approaches have significantly altered the management of patients with cerebral venous thrombosis. In contrast to previously held beliefs, cerebral venous thrombosis is considered to be a relatively benign disease with an overall favourable prognosis. Mortality is <10%, and the vast majority of patients recover completely. Although the efficacy of heparin has not been unequivocally proven, it is employed in most centres as the standard therapy. There are not sufficient data supporting long-term anticoagulation. In patients with a proven hypercoagulability syndrome, anticoagulation therapy is generally recommended for a period of 6 months. Whether patients with idiopathic thrombosis should also be treated remains controversial. Non-invasive MR and CT angiography techniques have largely replaced conventional angiography for initial evaluation and follow-up examinations. Both methods have a high sensitivity for cerebral venous thrombosis. Local fibrinolytic therapy or other aggressive recanalizing methods can not be generally recommended.

Angiographic follow-up of vertebrobasilar artery aneurysms treated with detachable coils

Endovascular treatment of ruptured vertebrobasilar artery aneurysms with Gugliemi detachable coils (GDC) has become an alternative to surgery. Mid-term angiographic follow-up can now be reported. Of 111 vertebrobasilar aneurysms in 110 patients we treated with GDC since 1992, 53 underwent angiography within 1 year and 59 after more than 18 months. We did not achieve complete occlusion on initial treatment of 23 aneurysms (21%). Complications were observed in 19 patients (17%), leading to permanent clinical disability in eight. Enlargement of the neck or reopening was seen in 12 (23%) of 53 aneurysms followed by angiography within 12 months. Documented recanalisation was treated in four (8%). Angiography was performed after 18-78 months in 59 patients, of whom nine, including three with initially incomplete occlusions, were retreated with GDC. Within the entire second observation period, three (5%) of the 59 patients had a further haemorrhage and were retreated with GDC. Rebleeding proved to be the only factor influencing the clinical outcome of retreated patients.

[Diagnostic and therapeutical considerations in the treatment of giant aneurysms]

The treatment of giant aneurysms requires a thorough surgical and endovascular planning as this entity is accompanied by complex vascular and blood flow particularities. Even in experienced neurovascular centers the clinical outcome varies considerably. Within a series of 1386 aneurysm patients 72 (5%) giant (>25 mm) aneurysms were treated in our institution. Their age ranged between 26 and 81 years (medium age 52 years). 22 patients were suffering of a subarachnoid hemorrhage (SAH). Additionally there were 50 patients with nerve palsies or unspecific symptoms due to unruptured giant aneurysms (UGA). Treatment modalities included surgical clipping (n = 35), balloon occlusion of the ICA (n = 12), endovascular coiling (n = 7) or a combined regimen of balloon occlusion, surgical clipping and EC-IC bypass (n = 8). 10 patients could not be treated on due to their high age or minor clinical status (H&H IV and V). 6 of 15 (40%) SAH-patients were discharged without any complaints compared to 26% (12 of 47 patients) in the group of unruptured aneurysms. 1 SAH-patients (7%) versus 13 UGA (28%) patients suffered persisting nerve palsies or minor neurological disorders. 32% (n = 15) of the UGA-patients were suffering of major neurological deficits and required further professional help. 5 patients remained in a vegetative state, 3 of these had been admitted with an incidental finding of an UGA. 6 of 15 (40%) SAH-patients died, 5 of them admitted with H&H grade IV or V. However only 3 of 47 (6%) UGA patients died. 2 of these had a fatal SAH before treatment, 1 underwent EC-IC bypass surgery with insufficient hemispheric vascularization followed by gross infarction. The clinical status and age of the patient are significant factors influencing treatment associated morbidity and mortality. The individual vascular situation may lead to a complex therapeutical regimen thereby predisposes higher complication rates. We believe that surgical clipping is the first choice of treatment allowing temporarily clipping and reconstruction of the normal anatomy by shrinking or/and reconstructive clipping while reducing the mass effect. Whereas endovascular coiling alone is less favorable due to the packing of the coils a combined endovascular and surgical approach have to be considered in selected cases.

Outcome after endovascular therapy of ruptured intracranial aneurysms: morbidity and impact of rebleeding

We evaluated midterm functional outcome after endovascular occlusion of aneurysms in patients with subarachnoid haemorrhage (SAH) and determined the incidence of late rebleeding as an additional prognostic parameter. We treated 79 consecutive patients with SAH from an intracranial aneurysm admitted from a neurological intensive care unit by the endovascular route between 1993 and 1997 and 52 survivors were followed up in 1999-2000. The mean interval between SAH and follow-up was 41 months (range 13-74 months). Outcome was determined by the Glasgow outcome (GOS) and Rankin (RS) scales and by questions concerning neuropsychological disorders. The patients were analysed according to Hunt and Hess (H & H) grades I-III or IV-V on admission. We observed two episodes of rebleeding (3%) with impact on outcome at 907 and 2010 days after SAH, respectively. A complete recovery (GOS 5) was achieved in 53% of H & H grade I-III and 17% of grade IV-V patients; with death rates 19% and 50%, and morbidity according to the RS (5-2) 18% and 29%, respectively. Midterm morbidity after endovascular therapy is thus low. Rebleeding with an impact on outcome can be observed up to 2010 days after SAH, suggesting that long-term angiographic follow-up is indispensable.

Three-dimensional pulsatile flow simulation before and after endovascular coil embolization of a terminal cerebral aneurysm

The effect of different percentages of coil mesh in a cerebral aneurysm on the pulsatile flow and pressure in the parent vessel and aneurysm lumen was evaluated. Geometric data on a basilar tip aneurysm and vertebrobasilar arteries after subarachnoid hemorrhage was obtained by computer tomographic angiography. Intraarterial pressure was measured at four vertebrobasilar points before and after treatment with detachable coils. Pulsatile flow was documented by transcranial ultrasonography. A three-dimensional computer simulation was created using a commercial fluid dynamics solver for four aneurysm conditions: (1) before intervention; (2) with a 20% filling showing a complete cessation of the inflow through the aneurysm neck; (3) with a 12% filling showing an incomplete deceleration of inflow through the aneurysm neck, with a remaining flow around the embedded platinum coils; and (4) with a 12% filling and simulation of clotted aneurysm dome, which did not inhibit persisting flow phenomena. The relative pressure amplitudes neither increased nor decreased under the different simulated aneurysm filling conditions. Inserted platinum coils can immediately and decisively relieve the influx of pulsating blood and allow for initial clotting. To reach this effect, a volume density of 20% platinum coil mesh in the aneurysm neck is needed.

Comparison of operative and endovascular treatment of anterior circulation aneurysms in patients in poor grades

We assessed the outcome of surgical and endovascular treatment in patients in poor (Hunt & Hess IV or V) grade following subarachnoid haemorrhage due to anterior circulation aneurysm (ACA). There were 41 patients, treated surgically (20), by the endovascular route (20) or both (1). The aneurysms were clipped in 20 patients, wrapped in one; 19 were treated with Guglielmi detachable coils (GDC), one by parent vessel occlusion using detachable balloons. One GDC treatment was interrupted and the aneurysm was surgically clipped instead. We treated five patients surgically to evacuate accompanying intracerebral clots. We treated 14 (66%) patients by the endovascular route and 15 (71%) surgically within 72 h of the haemorrhage. The frequency of delayed ischaemic neurological deficit and/or cerebral infarct due to vasospasm did not differ significantly between the endovascular and surgical groups. We had one surgical and three endovascular procedure-related complications with clinical manifestations. Outcome was evaluated after 6 months. After GDC treatment, angiographic follow-up was carried out between 8 and 26 months (mean 17 months). Good outcomes were achieved in six (29%) of the surgically treated patients (40% of the survivors) and six (30%) of the endovascular treatment patients (60% of the survivors). Outcome was similar after surgical and endovascular approaches. The decision as to which treatment to chosen is influenced mainly by clinical factors such as cerebral haematoma or age.

Operative or endovascular treatment of ruptured intracranial vertebral artery aneurysms?

Our purpose was to evaluate the surgical and endovascular treatment outcomes of ruptured intracranial vertebral artery aneurysms (RIVAA). The outcomes of 44 patients with RIVAA treated between 1983 and 1998 surgically (26), endovascularly (20) or both (2) were evaluated. The aneurysms were clipped in 24 patients, and clipped and wrapped in two. We treated 20 by the endovascular approach, 12 with Guglielmi detachable coils (GDC), and eight by parent-vessel occlusion using detachable balloons. Three patients had endovascular treatment after a failed or inadequate surgical attempt. Posttreatment follow-up was 17-183 months (mean 101 months) for surgically treated patients. For the GDC-treated group angiographic follow-up was carried at 8-49 months (mean 19 months). The condition of seven (27 %) of the surgically treated patients worsened due to procedure-related complications, compared with 10% in the endovascular treatment group. Of the patients initially presenting with Hunt and Hess grade IV or V, three of five (60%) died who were treated surgically and two of eight (25%) who were treated endovascularly. A good outcome was achieved in 17 surgically treated patients (85% of the survivors) and in 16 of the endovascular group (89% of the survivors). This present "same-site" report on treatment of a specific abnormality, RIVAA, treated surgically or by an endovascular approach indicates that especially in poorer Hunt and Hess grade patients, the latter may offer a clinical outcome as good as that of surgery, although long-term efficacy of GDC treatment is still to be determined.

Outcome after endovascular treatment of Hunt and Hess grade IV or V aneurysms: comparison of anterior versus posterior circulation

BACKGROUND AND PURPOSE

The most common cause of poor treatment outcome in patients suffering aneurysmal subarachnoid hemorrhage is cerebral vasospasm, especially in cases of poor Hunt and Hess grades (IV and V). A further prognostic factor in surgically treated patients is aneurysm localization. The aim of the present retrospective study is to compare the endovascular treatment outcome in such poor-grade patients according to aneurysm localization in either the anterior (AC) or posterior (PC) circulation.

METHODS

Forty poor-grade patients admitted between 1993 and July 1998 were treated by endovascular approach within 23 days after aneurysm rupture. Eighteen had aneurysms in the AC, 22 in the PC. Mean treatment delay was 4 days after rupture and median, 2 days. One patient showed multiple aneurysms. In 36 cases, aneurysms were occluded by Guglielmi detachable coils; in 4 cases, by parent vessel balloon occlusion.

RESULTS

The incidence of delayed ischemic neurological dysfunction or cerebral infarct due to vasospasm did not differ significantly between the AC and PC groups. Two procedure-related complications with clinical effect were observed in each group. At 6 months' follow-up, the result was good in 5 patients and poor in 13 in the AC group and good in 11 patients and poor in 11 in the PC group.

CONCLUSION

Given comparable incidence of vasospasm in poor-grade patients, a tendency toward better treatment outcome was found in patients with aneurysms in the posterior circulation (chi(2)=2.04; P=0.15) than in the anterior circulation. Endovascular therapy for poor-grade patients is recommended, as are further studies to determine treatment differences.

Two-step presurgical endovascular treatment of five arteriovenous malformations partially fed by single vessels en passage

PURPOSE

To describe a method for the preoperative embolization of arteriovenous malformations (AVM) containing vessels en passage (VeP). First, before embolization of the primary AVM, the distal portion of the VeP beyond the AVM, which supplies the parenchymal compartment, is blocked through placement of an endovascular ligature (fibered coils). This protects the post lesional parenchymal tissue and isolates malformational compartments before embolization. Thus the proximal AVM-supplying segment of the VeP can be safely embolized.

PATIENTS AND METHODS

Five of 204 AVM patients admitted for preoperative embolization between 1989 and 1997 fulfilled the following treatment criteria for the placement of an endovascular ligature in a VeP before embolization: 1. The diameter of the distal portion of the VeP behind the AVM was large whereas the parenchymal blush was poor; 2. The VeP fed a large portion of the AVM; 3. The VeP was judged to be accessible only late in the surgical procedure; 4. The VeP and its off branches were an integral part of the AVM periphery and thus not suitable for microdissection.

RESULTS

In all five cases the leptomeningeal collateral perfusion (the arterial supply to parenchymal brain areas) served to supply brain areas distal to the AVM after primary blockage of a VeP by endovascular ligature with fibered coils. Embolization and complete surgical dissection of the AVM was then achieved in all cases. No neurological deficits occurred.

CONCLUSION

Experience with our five cases indicates that a preparatory endovascular ligature of a VeP between parenchyma and the malformational compartment followed by embolization of the AVM can serve as an alternative to open surgical dissection of a vessel en passage and that it safely allows effective preoperative embolization.

[Removal of a cochlea implant with chronic granulation labyrinthitis and foreign body reaction]

BACKGROUND

Cochlea Implantation is an accepted treatment for children and adults with profound sensorineural deafness. In rare cases postoperative complications may occur so that removal of the implant is unavoidable.

CASE REPORT

In a particular case we present and discuss the case of a 69-year-old patient.

CONCLUSION

After removal of a cochlear implant, the electronic array is frequently left in the cochlea as a temporary replacement. This is a common practice, but whether it is advisable should be verified according to the specific intraoperative situation.

Subacute onset of oculogyric crises and generalized dystonia following intranasal administration of heroin

A case is reported of a patient who experienced sudden onset of severe respiratory failure, shock and coma after first-time intranasal heroin abuse. During the following days full consciousness was restored, revealing persistent oculogyric crises, axial retropulsive dystonia and ataxia. Initially computer tomography (CT) scans of the brain were normal and cerebral spinal fluid examination showed a slight elevation of lactate. Magnetic resonance imaging (MRI) scans of the brain demonstrated diffuse bilateral subcortical white matter hyperintensities, with sparing of the U-fibers, symmetric bilateral hyperintensities of the globus pallidum and very hyperintensive subcortical foci in the right hemisphere. Differential diagnostic assessment, treatment, clinical and MRI course of a 6-month follow-up are discussed.

Predicting hemodynamic ischemia by transcranial Doppler monitoring during therapeutic balloon occlusion of the internal carotid artery

PURPOSE

Our objective was to evaluate the sensitivity of transcranial Doppler (TCD) sonographic monitoring during permanent balloon occlusion of the internal carotid artery (ICA) in predicting hemodynamic ischemia.

METHODS

Thirty-two consecutive patients underwent controlled therapeutic balloon occlusion of the ICA. Selection criteria included assessment of the circle of Willis by compression angiography, clinical tolerance during a 20-minute test occlusion, and TCD monitoring of the ipsilateral middle cerebral artery. The mean blood flow velocity (MBFV) (n = 32) and pulsatility index (PI) (n = 28) were recorded. In 25 patients, MBFV changes upon motor stimulation were recorded before and after ICA occlusion.

RESULTS

Twenty-eight (88%) of the patients had no complications. Three patients suffered delayed symptoms 30 minutes to 20 hours after balloon detachment. Two of these patients recovered spontaneously within 1 day, the other improved after extracranial/intracranial (EC/IC) bypass surgery. One patient, who did not tolerate the test occlusion, suffered a hemodynamic stroke despite EC/IC bypass before permanent balloon occlusion. No embolic complications occurred. The mean MBFV reduction was 20% (range, 0% to 55%); the mean PI reduction was 20% (range, 0% to 56%). No complications occurred in patients who had mild MBFV and PI reduction (30% or less, n = 21). All three patients with severe MBFV or PI reduction (> 50%) had neurologic symptoms. Among those with moderate MBFV or PI reduction (30% to 50%, n = 8), symptoms developed in only one patient who had moderate reduction of both MBFV (33%) and PI (38%). Motor vasoreactivity showed wide variation and was markedly reduced in two symptomatic patients.

CONCLUSION

TCD monitoring reflects changes in cerebral hemodynamics after therapeutic balloon occlusion of the ICA. MBFV and PI reductions under 30% are highly predictive of clinical tolerance. A reduction of more than 50% may be a critical threshold for the occurrence of symptoms; in such cases, EC/IC bypass should be considered before proceeding with permanent balloon occlusion.