Guus Beute - Academia.edu (original) (raw)

Papers by Guus Beute

Research paper thumbnail of Endovascular Treatment of Posterior Cerebral Artery Aneurysms

RESULTS: All aneurysms were successfully treated, 17 with selective occlusion of the aneurysm wit... more RESULTS: All aneurysms were successfully treated, 17 with selective occlusion of the aneurysm with coils and 5 with simultaneous occlusion of the aneurysm and parent PCA with coils. There were no complications of treatment. Two patients died of sequelae of SAH shortly after treatment. One patient died 2 months after coiling of an unruptured P1 aneurysm with intramural thrombus of

Research paper thumbnail of Rooij WJ, Sluzewski M, Beute GN, et al.. Procedural complications of coiling of ruptured intracranial aneurysms: incidence and risk factors in a consecutive series of 681 patients

American Journal of Neuroradiology

To report the incidence of procedural complications of coiling of ruptured intracranial aneurysms... more To report the incidence of procedural complications of coiling of ruptured intracranial aneurysms leading to permanent disability or death in a consecutive series of 681 patients and to identify risk factors for these events.

Research paper thumbnail of Complications of balloon-assisted coil embolization of intracranial aneurysms - Response

Research paper thumbnail of Brain AVM embolization with Onyx

American Journal of Neuroradiology

To report the initial experience by using a new liquid embolic agent (Onyx) for embolization of b... more To report the initial experience by using a new liquid embolic agent (Onyx) for embolization of brain arteriovenous malformations (AVMs).

Research paper thumbnail of Dural arteriovenous fistulas with cortical venous drainage: Incidence, clinical presentation, and treatment

American Journal of Neuroradiology

BACKGROUND AND PURPOSE: Our purpose was to report our experience with intracranial dural arteriov... more BACKGROUND AND PURPOSE: Our purpose was to report our experience with intracranial dural arteriovenous fistulas (DAVFs) with cortical venous drainage during a 12-year period. PATIENTS AND METHODS: Between January 1994 and January 2006, 91 patients with intracranial DAVFs presented at our institution, and 29 (32%) had cortical venous drainage. There were 5 women and 24 men (mean age, 53.9 years; range, 24 -77). Clinical presentation was intraparenchymal or subarachnoid hemorrhage in 18 patients (62%), seizures in 4 patients (14%), visual symptoms in 2 patients (7%), pulsatile bruit in 1 patient (3%), and the DAVF (14%) was incidentally discovered in 4 patients.

Research paper thumbnail of Late rebleeding of ruptured intracranial aneurysms treated with detachable coils

American Journal of Neuroradiology

The purpose of this study was to assess the incidence of late rebleeding of ruptured intracranial... more The purpose of this study was to assess the incidence of late rebleeding of ruptured intracranial aneurysms treated with detachable coils. A clinical follow-up study was conducted in 393 consecutive patients with a ruptured aneurysm treated with detachable coils between January 1995 and January 2003. Late rebleeding was defined as recurrent hemorrhage from a coiled aneurysm >1 month after coiling. One patient was lost to follow-up. Total clinical follow-up of the 392 patients who were coiled for ruptured cerebral aneurysms was 18,708 months (1559 patient years; median, 48 months; mean, 47.7 months; range, 0-120 months). Four patients suffered late rebleeding from the coiled aneurysm at 8, 12, 30, and 40 months after coiling, respectively. Two of these patients died. Another patient died of probable rebleeding 4 months after coiling. The incidence of late rebleeding was 1.27% (5/393) and mortality of late rebleeding was 0.76% (3/393). The annual late rebleeding rate was 0.32%, and...

Research paper thumbnail of Coiling of truly incidental intracranial aneurysms

American Journal of Neuroradiology

The purpose of this study is to report the morbidity, mortality, and angiographic results of coil... more The purpose of this study is to report the morbidity, mortality, and angiographic results of coiling of asymptomatic incidental aneurysms and compare the characteristics of these aneurysms with other asymptomatic incidental aneurysms that were not treated. During a 10-year period, 97 patients without previous subarachnoid hemorrhage, presented with incidentally found intracranial aneurysms. In 48 patients, 58 aneurysms were coiled. The mean size of the 58 coiled incidental aneurysms was 10.9 mm (median, 9 mm; range, 3-40 mm). Twenty-six of 58 coiled aneurysms (44.8%) were > or = 10 mm. Permanent morbidity of coiling was 2.1% (1 of 48), mortality was 0%. Compared with untreated patients with incidental aneurysms, coiled patients were younger and more often had multiple aneurysms. Aneurysms of coiled patients more often had a small neck, were more often located on the carotid artery, and were less often located on the middle cerebral artery. Of 46 aneurysms with angiographic follow...

Research paper thumbnail of Radiotherapy for partially resected spinal ependymomas: A retrospective study of 60 cases

Oncology Reports, 2003

Ependymomas (Es) and myxopapillary ependymomas (mpEs) are the most common primary tumours of the ... more Ependymomas (Es) and myxopapillary ependymomas (mpEs) are the most common primary tumours of the spinal cord. Recurrence-free survival depends on local control of the tumour. The value of additional radiotherapy (RT) is still a matter of debate. The aim of this retrospective study was to analyse radiotherapy, surgery and the preoperative state with regard to recurrence rate and long-term neurological outcome. Sixty patients with spinal Es (40) and spinal mpEs (20) were included. According to local policy, 14 patients who underwent total resection and 20 patients with incomplete resection were irradiated postoperatively. Total resection was achieved in 34 of the 60 tumours. Preoperative state and long-term outcome was assessed according to a previously published scale. When postoperative RT was applied after partial resection, only 3 of 11 Es and 1 of 9 mpEs recurred. All partially resected non-radiated Es (n=3) and 2 of the 3 partially resected non-radiated mpEs recurred. There was no recurrence after total resection. Only one of 6 patients with disseminated mpEs had clinical symptoms caused by the disseminated tumour. Long-term neurological outcome was related to preoperative conditions with no difference between partially and totally resected tumours. Our study shows that RT is only beneficial for partially resected Es and mpEs. Local recurrence-free survival of spinal Es and mpEs is obtained by total resection. Long-term neurological outcome is related to preoperative conditions. Seeding is seen in mpEs and does not cause clinical symptoms in most of the patients.

Research paper thumbnail of How long does it take to coil an intracranial aneurysm?

Neuroradiology, 2008

Introduction The change in the treatment of choice for intracranial aneurysms from clipping to co... more Introduction The change in the treatment of choice for intracranial aneurysms from clipping to coiling has been associated with an important change in logistics. The time needed for coiling is variable and depends on many factors. In this study, we assessed the procedural time for the coiling of 642 aneurysms and tried to identify predictors of a long procedural time. Methods The procedural time for coiling was defined as the number of minutes between the first diagnostic angiographic run and the last angiographic run after embolization. Thus, induction of general anesthesia and catheterization of the first vessel were not included in the procedural time. A long procedural time was defined as the upper quartile of procedural times (70-158 min). Logistic regression analysis was performed for several variables. Results The mean procedural time was 57.3 min (median 52 min, range 15-158 min). More than half of the coiling procedures lasted between 30 and 60 min. Multiple logistic regression analysis identified the use of a supportive device (OR 5.4), procedural morbidity (OR 4.5) and large aneurysm size (OR 3.0) as independent predictors of a long procedural time. A poor clinical condition of the patient, the rupture status of the aneurysm, gender, the occurrence of procedural rupture, and aneurysm location were not related to a long procedural time. The mean time for the first 321 coiling procedures was not statistically significantly different from mean time for the last 321 procedures. Conclusion With optimal logistics, coiling of most intracranial aneurysms can be performed in one to two hours, including patient handling before and after the actual coiling procedure.

Research paper thumbnail of Tentorial artery embolization in tentorial dural arteriovenous fistulas

Neuroradiology, 2006

Introduction The tentorial artery is often involved in arterial supply to tentorial dural fistula... more Introduction The tentorial artery is often involved in arterial supply to tentorial dural fistulas. The hypertrophied tentorial artery is accessible to embolization, either with glue or with particles. Methods Six patients are presented with tentorial dural fistulas, mainly supplied by the tentorial artery. Two patients presented with intracranial hemorrhage, two with pulsatile tinnitus and one with progressive tetraparesis, and in one patient the tentorial dural fistula was an incidental finding. Different endovascular techniques were used to embolize the tentorial artery in the process of endovascular occlusion of the fistulas. Results All six tentorial dural fistulas were completely occluded by endovascular techniques, confirmed at followup angiography. There were no complications. When direct catheterization of the tentorial artery was possible, glue injection with temporary balloon occlusion of the internal carotid artery at the level of the tentorial artery origin was effective and safe. Conclusion Different endovascular techniques may be successfully applied to embolize the tentorial artery in the treatment of tentorial dural fistulas.

Research paper thumbnail of Superior cerebellar artery aneurysms: incidence, clinical presentation and midterm outcome of endovascular treatment

Neuroradiology, 2007

Introduction The aim of this retrospective study was to determine the incidence, clinical present... more Introduction The aim of this retrospective study was to determine the incidence, clinical presentation and midterm clinical and imaging outcome of endovascular treatment of 34 superior cerebellar artery (SCA) aneurysms in 33 patients. aneurysms were treated in our institution, and 36 aneurysms in 35 patients were located on the SCA (incidence 1.7%). Two of three distal SCA aneurysms were excluded. All the remaining 34 SCA aneurysms, of which 22 (65%) were ruptured and 12 (35%) were unruptured, in 33 patients were treated by endovascular techniques. There were 6 men and 27 women ranging from 29-72 years. In 14 patients (42%) multiple aneurysms were present. Results Initial angiographic occlusion was (near) complete in 32 aneurysms (94%) and incomplete in 2 aneurysms (6%). Complications leading to permanent morbidity or death occurred in two patients (6.1%, 95% CI 0.6 to 20.60%). Outcome at 6 months follow-up in 31 surviving patients was GOS5 in 26 (84%), GOS4 in 4 (13%) and GOS3 in 1 patient (3%). There were no episodes of (re) bleeding during 118 patient-years of follow-up. The 6month angiographic follow up in 28 SCA aneurysms and extended angiographic follow-up in 19 showed stable occlusion in 27 aneurysms. No additional treatments were performed.

Research paper thumbnail of Intracranial aneurysms that repeatedly reopen over time after coiling: imaging characteristics and treatment outcome

Neuroradiology, 2007

Background and Purpose: To report incidence, imaging-and clinical characteristics of patients wit... more Background and Purpose: To report incidence, imaging-and clinical characteristics of patients with aneurysms that repeatedly reopened over time and were coiled three times or more during follow up of 2-11 years.

Research paper thumbnail of Reversibility of lumbar epidural lipomatosis in obese patients after weight-reduction diet

Neuroradiology, 1995

We present three obese patients with symptomatic lumbar epidural lipomatosis. All three were trea... more We present three obese patients with symptomatic lumbar epidural lipomatosis. All three were treated with a calorie-controlled diet and considerable weight reduction was achieved. MRI demonstrated a reduction in the epidural fat and relief of thecal sac compression in all three; two also improved clinically.

Research paper thumbnail of Intramedullary lipoma

Neuroradiology, 1996

We present a unique case of intramedullary lipoma, diagnosed on MRI and confirmed at surgery.

Research paper thumbnail of Internal carotid bifurcation aneurysms: frequency, angiographic anatomy and results of coiling in 50 aneurysms

Neuroradiology, 2008

Introduction Internal carotid artery (ICA) bifurcation aneurysms are uncommon. Little is known ab... more Introduction Internal carotid artery (ICA) bifurcation aneurysms are uncommon. Little is known about incidence, anatomical characteristics and results of endovascular treatment. We report our experience with endovascular treatment of 50 ICA bifurcation aneurysms in 46 patients. Methods There were 13 men (28%) and 33 women (72%) with a mean age of 49.3 years (range 23-76 years). Of 50 aneurysms, 26 (52%) were ruptured and 24 (48%) were unruptured. Of the 46 patients, 23 (50%) had one to five additional aneurysms. Results The frequency of ICA bifurcation aneurysms was 2.4% (53 of 2,249, 95% CI 1.8-3.1%). Their mean size was 9.6 mm (median 6 mm, range 2-55 mm). Aneurysm neck was symmetrically on A1 and M1 in 30 aneurysms (60%), dominant on A1 in 14 (28%), on M1 in 2 (4%) and on the ICA in 4 (8%). Aneurysm fundus projection was superior in 28 aneurysms (56%), posterior in 9 (18%), anterior in 10 (20%) and lateral in 3 (6%). Four aneurysms were coiled with balloon assistance. Procedural morbidity and mortality of coiling was 2% each. During follow-up, 7 of 50 aneurysms (all 10 mm or larger) were additionally treated (retreatment rate 14%). Conclusion ICA bifurcation aneurysms are rare with a frequency of 2.4% of treated aneurysms in our institution. They are often associated with additional aneurysms. Most aneurysm necks are located symmetrically on A1 and M1 and fundus projection is mostly superior. Coiling is safe and effective for the management of these aneurysms. The aneurysms that needed retreatment were ≥10 mm.

Research paper thumbnail of Cognitive and radiological effects of radiotherapy in patients with low-grade glioma: long-term follow-up

The Lancet Neurology, 2009

Background Our previous study on cognitive functioning among 195 patients with low-grade glioma (... more Background Our previous study on cognitive functioning among 195 patients with low-grade glioma (LGG) a mean of 6 years after diagnosis suggested that the tumour itself, rather than the radiotherapy used to treat it, has the most deleterious eff ect on cognitive functioning; only high fraction dose radiotherapy (>2 Gy) resulted in signifi cant added cognitive deterioration. The present study assesses the radiological and cognitive abnormalities in survivors of LGG at a mean of 12 years after fi rst diagnosis.

Research paper thumbnail of Unilateral pallidotomy in Parkinson's disease: a randomised, single-blind, multicentre trial

The Lancet, 1999

The results of several cohort studies suggest that patients with advanced Parkinson&#... more The results of several cohort studies suggest that patients with advanced Parkinson's disease would benefit from unilateral pallidotomy. We have assessed the efficacy of unilateral pallidotomy in a randomised, single-blind, multicentre trial. We enrolled 37 patients with advanced Parkinson's disease who had, despite optimum pharmacological treatment, at least one of the following symptoms: severe response fluctuations, dyskinesias, painful dystonias, or bradykinesia. Patients were randomly assigned to unilateral pallidotomy within 1 month or to pallidotomy after the primary outcome assessment (6 months later). The primary outcome was the difference between the groups in median changes on the motor examination section of the unified Parkinson's disease rating scale (UPDRS 3) score done in the off phase. Secondary outcome measures included levodopa-induced dyskinesias (dyskinesia rating scale [DRS]) and extent of disability (UPDRS 2). The median UPDRS 3 off score of the pallidotomy patients improved from 47 to 32.5, whereas that of control patients slightly worsened from 52.5 to 56.5 (p<0.001). In the on phase the median DRS score improved 50% in pallidotomy patients compared with no change in controls. The UPDRS 2 off score improved with a median of 7 in the pallidotomy group. Two treated patients had major adverse effects. Unilateral pallidotomy is an effective treatment in patients with advanced Parkinson's disease, who have an unsatisfactory response to pharmacological treatment.

Research paper thumbnail of A young woman with a first-time seizure and a huge intracranial vascular structure

The Lancet, 2013

A 27-year-old woman presented with a fi rst-time seizure. MRI of the head showed a large, 7 cm, r... more A 27-year-old woman presented with a fi rst-time seizure. MRI of the head showed a large, 7 cm, round vascular structure inside the right lateral ventricle with mass-eff ect (fi gure A). Simultaneous right carotid and vertebral angi ography (fi gure B and video 1) showed a direct high-fl ow arteriovenous shunt (fi gure B, arrow) between the right posterior cerebral artery and a grossly dilated sub ependymal ventricular vein. An aneurysm on the supra clinoid internal carotid artery was also seen (fi gure B, arrowhead). A microballoon catheter was fl ow directed to the aff erent artery and a second microcatheter positioned just distal to the balloon (fi gure C, arrow points to tip of catheter). With the balloon infl ated, the fl ow stopped and ethyl-vinylalcohol-copolymer glue (EVOH, Onyx, ev3, Raynham, MA, USA) could be slowly injected distal to the balloon just proximal to the shunt (fi gure D, arrow). The shunt Figure: Pial arteriovenous fi stula (A) MRI of the head showing a large, round vascular structure inside the right lateral ventricle. (B) Simultaneous right carotid and vertebral angiography showing a direct high-fl ow arteriovenous shunt (arrow) between the right posterior cerebral artery, a grossly dilated subependymal ventricular vein, and an aneurysm on the supraclinoid internal carotid artery (arrowhead). (C) A microballoon catheter being fl ow directed to the aff erent artery and a second microcatheter positioned distal to the balloon (arrow points to tip of catheter). (D) Ethyl-vinyl-alcohol-copolymer glue injected distal to the balloon just proximal to the shunt (arrow). The carotid aneurysm was occluded with coils (arrowhead). (E) Control angiography showing closure of the shunt and the aneurysm. (F) MRI of the head the next day showing the decreased size of the dilated vein.

Research paper thumbnail of Effect of radiotherapy and other treatment-related factors on mid-term to long-term cognitive sequelae in low-grade gliomas: a comparative study

Research paper thumbnail of Embolization of spinal dural arteriovenous fistulas: importance of occlusion of the draining vein

Journal of Neurosurgery: Spine, 2005

spinal dural arteriovenous fistula is an acquired, abnormal arteriovenous shunt between a dural b... more spinal dural arteriovenous fistula is an acquired, abnormal arteriovenous shunt between a dural branch of a segmental spinal artery and a radicular vein that drains the perimedullary venous system. 5 The fistula leads to increased venous pressure and venous congestion of the spinal cord, resulting in progressive myelopathy. Surgical and endovascular interventions are aimed at closure of the fistula, thereby disconnecting the draining vein and restoring normal venous spinal cord drainage.

Research paper thumbnail of Endovascular Treatment of Posterior Cerebral Artery Aneurysms

RESULTS: All aneurysms were successfully treated, 17 with selective occlusion of the aneurysm wit... more RESULTS: All aneurysms were successfully treated, 17 with selective occlusion of the aneurysm with coils and 5 with simultaneous occlusion of the aneurysm and parent PCA with coils. There were no complications of treatment. Two patients died of sequelae of SAH shortly after treatment. One patient died 2 months after coiling of an unruptured P1 aneurysm with intramural thrombus of

Research paper thumbnail of Rooij WJ, Sluzewski M, Beute GN, et al.. Procedural complications of coiling of ruptured intracranial aneurysms: incidence and risk factors in a consecutive series of 681 patients

American Journal of Neuroradiology

To report the incidence of procedural complications of coiling of ruptured intracranial aneurysms... more To report the incidence of procedural complications of coiling of ruptured intracranial aneurysms leading to permanent disability or death in a consecutive series of 681 patients and to identify risk factors for these events.

Research paper thumbnail of Complications of balloon-assisted coil embolization of intracranial aneurysms - Response

Research paper thumbnail of Brain AVM embolization with Onyx

American Journal of Neuroradiology

To report the initial experience by using a new liquid embolic agent (Onyx) for embolization of b... more To report the initial experience by using a new liquid embolic agent (Onyx) for embolization of brain arteriovenous malformations (AVMs).

Research paper thumbnail of Dural arteriovenous fistulas with cortical venous drainage: Incidence, clinical presentation, and treatment

American Journal of Neuroradiology

BACKGROUND AND PURPOSE: Our purpose was to report our experience with intracranial dural arteriov... more BACKGROUND AND PURPOSE: Our purpose was to report our experience with intracranial dural arteriovenous fistulas (DAVFs) with cortical venous drainage during a 12-year period. PATIENTS AND METHODS: Between January 1994 and January 2006, 91 patients with intracranial DAVFs presented at our institution, and 29 (32%) had cortical venous drainage. There were 5 women and 24 men (mean age, 53.9 years; range, 24 -77). Clinical presentation was intraparenchymal or subarachnoid hemorrhage in 18 patients (62%), seizures in 4 patients (14%), visual symptoms in 2 patients (7%), pulsatile bruit in 1 patient (3%), and the DAVF (14%) was incidentally discovered in 4 patients.

Research paper thumbnail of Late rebleeding of ruptured intracranial aneurysms treated with detachable coils

American Journal of Neuroradiology

The purpose of this study was to assess the incidence of late rebleeding of ruptured intracranial... more The purpose of this study was to assess the incidence of late rebleeding of ruptured intracranial aneurysms treated with detachable coils. A clinical follow-up study was conducted in 393 consecutive patients with a ruptured aneurysm treated with detachable coils between January 1995 and January 2003. Late rebleeding was defined as recurrent hemorrhage from a coiled aneurysm >1 month after coiling. One patient was lost to follow-up. Total clinical follow-up of the 392 patients who were coiled for ruptured cerebral aneurysms was 18,708 months (1559 patient years; median, 48 months; mean, 47.7 months; range, 0-120 months). Four patients suffered late rebleeding from the coiled aneurysm at 8, 12, 30, and 40 months after coiling, respectively. Two of these patients died. Another patient died of probable rebleeding 4 months after coiling. The incidence of late rebleeding was 1.27% (5/393) and mortality of late rebleeding was 0.76% (3/393). The annual late rebleeding rate was 0.32%, and...

Research paper thumbnail of Coiling of truly incidental intracranial aneurysms

American Journal of Neuroradiology

The purpose of this study is to report the morbidity, mortality, and angiographic results of coil... more The purpose of this study is to report the morbidity, mortality, and angiographic results of coiling of asymptomatic incidental aneurysms and compare the characteristics of these aneurysms with other asymptomatic incidental aneurysms that were not treated. During a 10-year period, 97 patients without previous subarachnoid hemorrhage, presented with incidentally found intracranial aneurysms. In 48 patients, 58 aneurysms were coiled. The mean size of the 58 coiled incidental aneurysms was 10.9 mm (median, 9 mm; range, 3-40 mm). Twenty-six of 58 coiled aneurysms (44.8%) were > or = 10 mm. Permanent morbidity of coiling was 2.1% (1 of 48), mortality was 0%. Compared with untreated patients with incidental aneurysms, coiled patients were younger and more often had multiple aneurysms. Aneurysms of coiled patients more often had a small neck, were more often located on the carotid artery, and were less often located on the middle cerebral artery. Of 46 aneurysms with angiographic follow...

Research paper thumbnail of Radiotherapy for partially resected spinal ependymomas: A retrospective study of 60 cases

Oncology Reports, 2003

Ependymomas (Es) and myxopapillary ependymomas (mpEs) are the most common primary tumours of the ... more Ependymomas (Es) and myxopapillary ependymomas (mpEs) are the most common primary tumours of the spinal cord. Recurrence-free survival depends on local control of the tumour. The value of additional radiotherapy (RT) is still a matter of debate. The aim of this retrospective study was to analyse radiotherapy, surgery and the preoperative state with regard to recurrence rate and long-term neurological outcome. Sixty patients with spinal Es (40) and spinal mpEs (20) were included. According to local policy, 14 patients who underwent total resection and 20 patients with incomplete resection were irradiated postoperatively. Total resection was achieved in 34 of the 60 tumours. Preoperative state and long-term outcome was assessed according to a previously published scale. When postoperative RT was applied after partial resection, only 3 of 11 Es and 1 of 9 mpEs recurred. All partially resected non-radiated Es (n=3) and 2 of the 3 partially resected non-radiated mpEs recurred. There was no recurrence after total resection. Only one of 6 patients with disseminated mpEs had clinical symptoms caused by the disseminated tumour. Long-term neurological outcome was related to preoperative conditions with no difference between partially and totally resected tumours. Our study shows that RT is only beneficial for partially resected Es and mpEs. Local recurrence-free survival of spinal Es and mpEs is obtained by total resection. Long-term neurological outcome is related to preoperative conditions. Seeding is seen in mpEs and does not cause clinical symptoms in most of the patients.

Research paper thumbnail of How long does it take to coil an intracranial aneurysm?

Neuroradiology, 2008

Introduction The change in the treatment of choice for intracranial aneurysms from clipping to co... more Introduction The change in the treatment of choice for intracranial aneurysms from clipping to coiling has been associated with an important change in logistics. The time needed for coiling is variable and depends on many factors. In this study, we assessed the procedural time for the coiling of 642 aneurysms and tried to identify predictors of a long procedural time. Methods The procedural time for coiling was defined as the number of minutes between the first diagnostic angiographic run and the last angiographic run after embolization. Thus, induction of general anesthesia and catheterization of the first vessel were not included in the procedural time. A long procedural time was defined as the upper quartile of procedural times (70-158 min). Logistic regression analysis was performed for several variables. Results The mean procedural time was 57.3 min (median 52 min, range 15-158 min). More than half of the coiling procedures lasted between 30 and 60 min. Multiple logistic regression analysis identified the use of a supportive device (OR 5.4), procedural morbidity (OR 4.5) and large aneurysm size (OR 3.0) as independent predictors of a long procedural time. A poor clinical condition of the patient, the rupture status of the aneurysm, gender, the occurrence of procedural rupture, and aneurysm location were not related to a long procedural time. The mean time for the first 321 coiling procedures was not statistically significantly different from mean time for the last 321 procedures. Conclusion With optimal logistics, coiling of most intracranial aneurysms can be performed in one to two hours, including patient handling before and after the actual coiling procedure.

Research paper thumbnail of Tentorial artery embolization in tentorial dural arteriovenous fistulas

Neuroradiology, 2006

Introduction The tentorial artery is often involved in arterial supply to tentorial dural fistula... more Introduction The tentorial artery is often involved in arterial supply to tentorial dural fistulas. The hypertrophied tentorial artery is accessible to embolization, either with glue or with particles. Methods Six patients are presented with tentorial dural fistulas, mainly supplied by the tentorial artery. Two patients presented with intracranial hemorrhage, two with pulsatile tinnitus and one with progressive tetraparesis, and in one patient the tentorial dural fistula was an incidental finding. Different endovascular techniques were used to embolize the tentorial artery in the process of endovascular occlusion of the fistulas. Results All six tentorial dural fistulas were completely occluded by endovascular techniques, confirmed at followup angiography. There were no complications. When direct catheterization of the tentorial artery was possible, glue injection with temporary balloon occlusion of the internal carotid artery at the level of the tentorial artery origin was effective and safe. Conclusion Different endovascular techniques may be successfully applied to embolize the tentorial artery in the treatment of tentorial dural fistulas.

Research paper thumbnail of Superior cerebellar artery aneurysms: incidence, clinical presentation and midterm outcome of endovascular treatment

Neuroradiology, 2007

Introduction The aim of this retrospective study was to determine the incidence, clinical present... more Introduction The aim of this retrospective study was to determine the incidence, clinical presentation and midterm clinical and imaging outcome of endovascular treatment of 34 superior cerebellar artery (SCA) aneurysms in 33 patients. aneurysms were treated in our institution, and 36 aneurysms in 35 patients were located on the SCA (incidence 1.7%). Two of three distal SCA aneurysms were excluded. All the remaining 34 SCA aneurysms, of which 22 (65%) were ruptured and 12 (35%) were unruptured, in 33 patients were treated by endovascular techniques. There were 6 men and 27 women ranging from 29-72 years. In 14 patients (42%) multiple aneurysms were present. Results Initial angiographic occlusion was (near) complete in 32 aneurysms (94%) and incomplete in 2 aneurysms (6%). Complications leading to permanent morbidity or death occurred in two patients (6.1%, 95% CI 0.6 to 20.60%). Outcome at 6 months follow-up in 31 surviving patients was GOS5 in 26 (84%), GOS4 in 4 (13%) and GOS3 in 1 patient (3%). There were no episodes of (re) bleeding during 118 patient-years of follow-up. The 6month angiographic follow up in 28 SCA aneurysms and extended angiographic follow-up in 19 showed stable occlusion in 27 aneurysms. No additional treatments were performed.

Research paper thumbnail of Intracranial aneurysms that repeatedly reopen over time after coiling: imaging characteristics and treatment outcome

Neuroradiology, 2007

Background and Purpose: To report incidence, imaging-and clinical characteristics of patients wit... more Background and Purpose: To report incidence, imaging-and clinical characteristics of patients with aneurysms that repeatedly reopened over time and were coiled three times or more during follow up of 2-11 years.

Research paper thumbnail of Reversibility of lumbar epidural lipomatosis in obese patients after weight-reduction diet

Neuroradiology, 1995

We present three obese patients with symptomatic lumbar epidural lipomatosis. All three were trea... more We present three obese patients with symptomatic lumbar epidural lipomatosis. All three were treated with a calorie-controlled diet and considerable weight reduction was achieved. MRI demonstrated a reduction in the epidural fat and relief of thecal sac compression in all three; two also improved clinically.

Research paper thumbnail of Intramedullary lipoma

Neuroradiology, 1996

We present a unique case of intramedullary lipoma, diagnosed on MRI and confirmed at surgery.

Research paper thumbnail of Internal carotid bifurcation aneurysms: frequency, angiographic anatomy and results of coiling in 50 aneurysms

Neuroradiology, 2008

Introduction Internal carotid artery (ICA) bifurcation aneurysms are uncommon. Little is known ab... more Introduction Internal carotid artery (ICA) bifurcation aneurysms are uncommon. Little is known about incidence, anatomical characteristics and results of endovascular treatment. We report our experience with endovascular treatment of 50 ICA bifurcation aneurysms in 46 patients. Methods There were 13 men (28%) and 33 women (72%) with a mean age of 49.3 years (range 23-76 years). Of 50 aneurysms, 26 (52%) were ruptured and 24 (48%) were unruptured. Of the 46 patients, 23 (50%) had one to five additional aneurysms. Results The frequency of ICA bifurcation aneurysms was 2.4% (53 of 2,249, 95% CI 1.8-3.1%). Their mean size was 9.6 mm (median 6 mm, range 2-55 mm). Aneurysm neck was symmetrically on A1 and M1 in 30 aneurysms (60%), dominant on A1 in 14 (28%), on M1 in 2 (4%) and on the ICA in 4 (8%). Aneurysm fundus projection was superior in 28 aneurysms (56%), posterior in 9 (18%), anterior in 10 (20%) and lateral in 3 (6%). Four aneurysms were coiled with balloon assistance. Procedural morbidity and mortality of coiling was 2% each. During follow-up, 7 of 50 aneurysms (all 10 mm or larger) were additionally treated (retreatment rate 14%). Conclusion ICA bifurcation aneurysms are rare with a frequency of 2.4% of treated aneurysms in our institution. They are often associated with additional aneurysms. Most aneurysm necks are located symmetrically on A1 and M1 and fundus projection is mostly superior. Coiling is safe and effective for the management of these aneurysms. The aneurysms that needed retreatment were ≥10 mm.

Research paper thumbnail of Cognitive and radiological effects of radiotherapy in patients with low-grade glioma: long-term follow-up

The Lancet Neurology, 2009

Background Our previous study on cognitive functioning among 195 patients with low-grade glioma (... more Background Our previous study on cognitive functioning among 195 patients with low-grade glioma (LGG) a mean of 6 years after diagnosis suggested that the tumour itself, rather than the radiotherapy used to treat it, has the most deleterious eff ect on cognitive functioning; only high fraction dose radiotherapy (>2 Gy) resulted in signifi cant added cognitive deterioration. The present study assesses the radiological and cognitive abnormalities in survivors of LGG at a mean of 12 years after fi rst diagnosis.

Research paper thumbnail of Unilateral pallidotomy in Parkinson's disease: a randomised, single-blind, multicentre trial

The Lancet, 1999

The results of several cohort studies suggest that patients with advanced Parkinson&#... more The results of several cohort studies suggest that patients with advanced Parkinson's disease would benefit from unilateral pallidotomy. We have assessed the efficacy of unilateral pallidotomy in a randomised, single-blind, multicentre trial. We enrolled 37 patients with advanced Parkinson's disease who had, despite optimum pharmacological treatment, at least one of the following symptoms: severe response fluctuations, dyskinesias, painful dystonias, or bradykinesia. Patients were randomly assigned to unilateral pallidotomy within 1 month or to pallidotomy after the primary outcome assessment (6 months later). The primary outcome was the difference between the groups in median changes on the motor examination section of the unified Parkinson's disease rating scale (UPDRS 3) score done in the off phase. Secondary outcome measures included levodopa-induced dyskinesias (dyskinesia rating scale [DRS]) and extent of disability (UPDRS 2). The median UPDRS 3 off score of the pallidotomy patients improved from 47 to 32.5, whereas that of control patients slightly worsened from 52.5 to 56.5 (p<0.001). In the on phase the median DRS score improved 50% in pallidotomy patients compared with no change in controls. The UPDRS 2 off score improved with a median of 7 in the pallidotomy group. Two treated patients had major adverse effects. Unilateral pallidotomy is an effective treatment in patients with advanced Parkinson's disease, who have an unsatisfactory response to pharmacological treatment.

Research paper thumbnail of A young woman with a first-time seizure and a huge intracranial vascular structure

The Lancet, 2013

A 27-year-old woman presented with a fi rst-time seizure. MRI of the head showed a large, 7 cm, r... more A 27-year-old woman presented with a fi rst-time seizure. MRI of the head showed a large, 7 cm, round vascular structure inside the right lateral ventricle with mass-eff ect (fi gure A). Simultaneous right carotid and vertebral angi ography (fi gure B and video 1) showed a direct high-fl ow arteriovenous shunt (fi gure B, arrow) between the right posterior cerebral artery and a grossly dilated sub ependymal ventricular vein. An aneurysm on the supra clinoid internal carotid artery was also seen (fi gure B, arrowhead). A microballoon catheter was fl ow directed to the aff erent artery and a second microcatheter positioned just distal to the balloon (fi gure C, arrow points to tip of catheter). With the balloon infl ated, the fl ow stopped and ethyl-vinylalcohol-copolymer glue (EVOH, Onyx, ev3, Raynham, MA, USA) could be slowly injected distal to the balloon just proximal to the shunt (fi gure D, arrow). The shunt Figure: Pial arteriovenous fi stula (A) MRI of the head showing a large, round vascular structure inside the right lateral ventricle. (B) Simultaneous right carotid and vertebral angiography showing a direct high-fl ow arteriovenous shunt (arrow) between the right posterior cerebral artery, a grossly dilated subependymal ventricular vein, and an aneurysm on the supraclinoid internal carotid artery (arrowhead). (C) A microballoon catheter being fl ow directed to the aff erent artery and a second microcatheter positioned distal to the balloon (arrow points to tip of catheter). (D) Ethyl-vinyl-alcohol-copolymer glue injected distal to the balloon just proximal to the shunt (arrow). The carotid aneurysm was occluded with coils (arrowhead). (E) Control angiography showing closure of the shunt and the aneurysm. (F) MRI of the head the next day showing the decreased size of the dilated vein.

Research paper thumbnail of Effect of radiotherapy and other treatment-related factors on mid-term to long-term cognitive sequelae in low-grade gliomas: a comparative study

Research paper thumbnail of Embolization of spinal dural arteriovenous fistulas: importance of occlusion of the draining vein

Journal of Neurosurgery: Spine, 2005

spinal dural arteriovenous fistula is an acquired, abnormal arteriovenous shunt between a dural b... more spinal dural arteriovenous fistula is an acquired, abnormal arteriovenous shunt between a dural branch of a segmental spinal artery and a radicular vein that drains the perimedullary venous system. 5 The fistula leads to increased venous pressure and venous congestion of the spinal cord, resulting in progressive myelopathy. Surgical and endovascular interventions are aimed at closure of the fistula, thereby disconnecting the draining vein and restoring normal venous spinal cord drainage.