Double-clip technique for the microneurosurgical management of very small (< 3 mm) intracranial aneurysms.

BACKGROUND: The treatment of very small (≤ 3 mm) aneurysms is technically challenging. Mini-clips used for clipping these small aneurysms have a smaller closing force compared with standard clips. OBJECTIVE: To describe the double-clip technique for very small aneurysms. METHODS: The double-clip technique, a parallel duplication clipping technique of booster clipping, is used by the senior author for clipping very small aneurysms with morphology suitable for the application of 2 clips. The aneurysm is clipped after application of temporary clip(s), administration of adenosine, or both. An initial mini-clip is applied, leaving a small residual neck sufficient for application of the second mini-clip. A second mini-clip of the same size and shape is applied on the residual neck parallel to the initial clip. The initially applied mini-clip, which is in close contact with the second clip, supports the second clip and prevents its slippage. This technique was retrospectively reviewed over a 13-year period (1997-2009). There were 3246 patients with 4757 aneurysms treated in the same period. RESULTS: The outcomes of 39 patients with 40 very small aneurysms clipped with the double-clip technique were analyzed. None of the patients had technique-related complications. Postoperative angiograms revealed complete aneurysm occlusion of 39 aneurysms and a small residual neck in 1 aneurysm. No parent artery obstruction was observed in the postoperative angiogram. CONCLUSION: The double-clip technique is a safe and effective variation of booster clipping in the treatment of very small aneurysms with suitable morphology.

Subgaleo-peritoneal shunt: An effective and safer alternative to lumboperitoneal shunt in the management of persistent or recurrent iatrogenic cranial pseudomeningoceles.

Subgaleo-peritoneal (SP) shunting for pseudomeningoceles (PMCs) is an effective and safer alternative as compared to the lumboperitoneal (LP) shunt. SP shunting was done in six patients (14-60 years) with persistent or recurrent PMCs using the cranial (ventricular part) and the distal parts of a Chhabra shunt connected by a rigid connector without any intervening chamber or valve. Two patients had undergone a prior LP shunt that had failed. One patient was unsuitable for a LP shunt placement. The PMC subsided completely in all the patients following the SP shunt. In one patient, the shunt got displaced and required repositioning. None of the patients developed symptoms of over-drainage or any other complication. All patients were asymptomatic at a mean follow-up of 15 months. These results suggest that SP shunting is a safe, simple, and effective alternative to the traditional LP shunt in the management of persistent or recurrent cranial PMCs.

A sacral arachnoid cyst causing holocord syringomyelia.

Spinal extradural arachnoid cysts (ACs) have an infrequent predilection for the sacrum. As with their counterparts in other regions of the spine, cysts in this location are mostly asymptomatic. Common presentations in symptomatic cases include pain in the low back or perineum, radiculopathy, and sphincteric dysfunction. The authors report a hitherto undescribed presentation in which the predominant symptoms are those related to an associated holocord syrinx. This 15-year-old boy presented with fluctuating, spastic paraparesis and a dissociated sensory loss in the trunk. Admission MR imaging of the spine showed an extradural AC from S-2 to S-4 and a holocord, nonenhancing syrinx. The patient underwent S-2 laminectomy, fenestration of the cyst, and partial excision of its wall. Intradural exploration revealed a normal-looking filum terminale and the absence of any dural communication with the cyst. At a follow-up visit 6 months after surgery, his motor and sensory deficits had resolved. Follow-up MR imaging showed complete resolution of the syrinx in the absence of the sacral AC. This is the first report of a sacral extradural AC causing holocord syringomyelia. Because conventional theories of syrinx formation were not helpful in elucidating this case, a hypothesis is postulated to explain the clinicoradiological oddity.

Two children with traumatic thoracic spinal epidural hematoma.

Traumatic spinal epidural hematomas in children are uncommon. Early diagnosis and prompt surgical evacuation is critical in these patients. We report two children with traumatic thoracic spine epidural hematomas with remarkable neurological recovery after surgical evacuation. Epidural hematoma with significant cord compression requires early diagnosis and emergency evacuation. This is crucial to expedite neurological recovery.

Gamma knife radiosurgery for arteriovenous malformations of basal ganglia, thalamus and brainstem--a retrospective study comparing the results with that for AVMs at other intracranial locations.

OBJECTIVE: The objective of this retrospective study was to study the outcome in patients with basal ganglia, thalamus and brainstem (central/deep) arteriovenous malformations (AVMs) treated with gamma knife radiosurgery (GKS) and to compare the results with that for AVMs at other intracranial locations. METHODS AND RESULTS: The results of 53 patients with central AVMs and 255 patients with AVMs at other locations treated with GKS at our center between April 1997 and March 2005 with minimum follow-up of 1 year were analyzed. CENTRAL AVMS: Forty of these 53 AVMs were Spetzler-Martin grade III, 11 were grade IV, and 2 were grade V. The mean AVM volume was 4.3 cm(3) (range 0.1-36.6 cm(3)). The mean marginal dose given was 23.3 Gy (range 16-25 Gy). The mean follow-up was 28 months (range 12-96 months). Check angiograms were advised at 2 years after GKS and yearly thereafter in the presence of residual AVM till 4 years. Presence of a residual AVM on an angiogram at 4 years after radiosurgery was considered as radiosurgical failure. Complete obliteration of the AVM was documented in 14 (74%) of the 19 patients with complete angiographic follow-up. Significantly lower obliteration rates (37% vs. 100%) were seen in larger AVMs (>3 cm(3)) and AVMs of higher (IV and V) Spetzler-Martin grades (28% vs. 100%). The 3- and 4-year actuarial rates of nidus obliteration were 68% and 74%, respectively. Eight patients (15%) developed radiation edema with a statistically significantly higher incidence in patients with AVM volume >3 cm(3) and in patients with Spetzler-Martin grade IV and V AVMs. Five patients (9.4%) had hemorrhage in the period of latency. COMPARISON OF RESULTS WITH AVMS AT OTHER LOCATIONS: Patients with central AVMs presented at a younger age (mean age 22.7 years vs. 29 years), with a very high proportion (81% vs. 63%) presenting with hemorrhage. Significantly higher incidence of radiation edema (15% vs. 5%) and lower obliteration rates (74% vs. 93%) were seen in patients with central AVMs. CONCLUSIONS: GKS is an effective modality of treatment for central AVMs, though relatively lower obliteration rates and higher complication rates are seen compared to AVMs at other locations.

Outcome after hemorrhage following Gamma Knife surgery for cerebral arteriovenous malformations.

OBJECT: Although the effects of Gamma Knife surgery (GKS) on the risk of hemorrhage are poorly understood, a certain subset of patients does suffer bleeding after GKS. This study was undertaken to analyze the outcome of patients sustaining hemorrhage after GKS; it is the most feared complication of radiosurgical management of cerebral arteriovenous malformations (AVMs). METHODS: Between May 1997 and June 2006, 494 cerebral AVMs in 489 patients were treated using a Leksell Gamma Knife Model B, and follow-up evaluations were conducted until June 2007 at the All India Institute of Medical Sciences in New Delhi. Fourteen patients who sustained a hemorrhage after GKS formed the study group. In most of these patients conservative management was chosen. RESULTS: The mortality rate was 0% and there was a 7% risk of sustaining a severe deficit following rebleeding after GKS. None of the patients sustained rebleeding after complete obliteration. Patients with Spetzler-Martin Grade III or less had increased chances of hemorrhage after GKS (p < 0.002). The presence of deep venous drainage, aneurysm, venous hypertension, or periventricular location on angiography was common in patients with hemorrhage after GKS. CONCLUSIONS: The risk of hemorrhage that remains following GKS for cerebral AVMs is highest in the 1st year after treatment. The present study showed a relatively good outcome even in cases with hemorrhage following GKS, with no deaths and minimal morbidity, further substantiating the safety and efficacy of the procedure.

Does hemorrhagic presentation in cerebral arteriovenous malformations affect obliteration rate after gamma knife radiosurgery?

OBJECTIVES: Radiosurgery has been widely adopted for the treatment of cerebral AVMs. However radiosurgical treatment of patients with hemorrhagic presentation is fraught with risk of rebleed during latency period. The present study intends to analyze the obliteration rate, time to obliteration and chances of rebleed in patients with hemorrhagic versus non-hemorrhagic clinical presentation in cerebral arteriovenous malformations (AVMs) treated with gamma knife radiosurgery (GKS). PATIENTS AND METHODS: Of all the patients with cerebral AVMs treated from May 1997 to June 2006, 157 patients with neuroimaging follow up with digital subtraction angiography harboring 160 AVM nidii formed the study group. The mean age of presentation was 28 years (range, 6-58 years); mean nidus volume being 3.64 cm3 (range, 0.011-36.6 cm3). The mean follow up period was 70 months (range, 13-121 months). All the patients were treated predominantly by primary GKS with use of adjunctive pre-GKS embolization in selected patients. RESULTS: A total of 103 (64%) patients presented with hemorrhage. There was no difference in the obliteration rate (69% versus 67%, p=0.672), mean latency period to obliteration (30 months versus 32 months, p=0.1989) and chances of hemorrhage (4.8% versus 3.5%, p=0.690) in patients with hemorrhagic as compared to non-hemorrhagic presentation. CONCLUSION: Prior hemorrhage does not affect the outcome after GKS in terms of obliteration rate, latency to obliteration as well as chances of hemorrhage during latency period. Gamma knife appears equally efficacious irrespective of the mode of clinical presentation in the management of cerebral AVMs; a concomitant use of pre-GKS embolization/surgery may be needed in patients with hemorrhagic presentation in selected cases, however.

Gross total excision of pediatric giant cystic craniopharyngioma with huge retroclival extension to the level of foramen magnum by anterior trans petrous approach: report of two cases and review of literature.

PURPOSE: Craniopharyngiomas with a large posterior fossa extension beyond the level of the foramen magnum are very rare and usually removed in two stages. The objective of this paper is to report that such rare cases of giant cystic predominantly retrochiasmatic retroclival craniopharyngiomas can be completely excised by an anterior transpetrous approach in a single stage. MATERIALS AND METHODS: The first case was a 6-year-old boy who presented with a 1-year history of recurrent episodes of seizures, headache, and vomiting. The second case was a 10-year-old girl who presented with history of headache, visual deterioration, and left-side hemiparesis for one and half years. Preoperative computed tomography (CT) and magnetic resonance imaging (MRI) in both these patients revealed a giant sellar suprasellar cystic lesion with areas of calcification and the lesion was predominantly retrochiasmatic with a huge retroclival posterior fossa extension down to the level of the C1 vertebra and laterally to the cerebellopontine angle. Gross total excision of both suprasellar and posterior fossa extensions could be done in both the patients through an anterior transpetrous transtentorial approach (Kawase's approach). RESULTS: Postoperative imaging (MRI/CT) revealed no obvious evidence of residual tumor. The first patient had right hemiparesis from which he recovered completely. The second patient died suddenly on postoperative day 4 after initial uneventful postoperative period, and the exact cause of death is not known. CONCLUSION: Giant cystic craniopharyngiomas, which are predominantly retrochiasmatic and associated with huge retroclival posterior fossa extensions, can be removed in single stage by Kawase's approach.

Gamma Knife surgery for intracranial arteriovenous malformations in children: a retrospective study in 103 patients.

OBJECT: This retrospective study was designed to study the outcome in children with intracranial arteriovenous malformations (AVMs) treated with Gamma Knife surgery (GKS). METHODS: One hundred and forty-two children were treated with GKS at the authors' institution between April 1997 and March 2006; of these, 103 patients with a mean follow-up of 26.4 months (range 6-96 months) were included. The mean age at presentation was 13.9 years (range 3-18 years). Eighty-six (83%) patients presented with hemorrhage. In 57 children the AVMs were Spetzler-Martin Grade I or II, and in 46 the AVMs were Grades III, IV, or V. The mean volume of the AVMs was 2.4 ml (range 0.04-23.3 ml). The mean marginal dose administered was 24.4 Gy (range 15-27 Gy). Follow-up angiography was advised at 2 years after GKS and yearly thereafter. In patients with residual AVMs, follow-up angiography was advised yearly until 4 years after GKS. If residual AVM was present, even on a follow-up angiogram obtained 4 years postsurgery, the GKS was considered a failure. RESULTS: Complete obliteration of the AVM was documented in 34 (87%) of the 39 patients with complete angiographic follow-up. The 3- and 4-year actuarial rates of nidus obliteration were 66 and 86% respectively. Three patients (2.9%) experienced bleeding during the latency period, and symptomatic radiation-induced edema was noted in four patients (3.8%). A significantly higher incidence of radiation edema was noted in patients with AVM volumes greater than 3 ml and in patients with Spetzler-Martin Grade IV and V AVMs. CONCLUSIONS: Gamma Knife radiosurgery is an effective modality for the treatment of intracranial AVMs in children, yielding high obliteration rates and low complication rates.

Surgical results in patients with tuberculosis of the spine and severe lower-extremity motor deficits: a retrospective study of 48 patients.

OBJECT: Significant numbers of patients with spinal tuberculosis (TB), especially in developing countries, still present late after disease onset with severe neurological deficits. The authors conducted a study to assess the outcome in these patients. METHODS: Fifty-nine patients with spinal TB and severe motor deficits underwent surgery at the authors' center during the past 10 years. Data obtained in 48 patients with a minimum of 3 months of follow up (mean follow-up period 12.8 months) were analyzed. The disease in 34 patients was characterized by Frankel Grade A/B (Medical Research Council Grade 0/5) and in 14 patients by Frankel Grade C (unable to walk even with support) at admission. Thirty (88%) of the 34 patients with Frankel Grade A/B status and 13 (92.8%) of the 14 patients with Frankel Grade C status at admission experienced improvement to Frankel Grade D/E (walking with or without support) at the last follow-up examination 3 or more months after surgery. The degree of improvement exhibited by patients with a Frankel Grade A/B spinal cord injury was comparable to that shown by patients with Frankel Grade C status. Even patients with flaccid paraplegia, gross sensory deficit, prolonged weakness, spinal cord signal changes demonstrated on magnetic resonance imaging, and bladder involvement have experienced dramatic improvement in motor function since surgery. A significant number of the patients have shown remarkable improvement in other symptoms such as pain (91.6%), spasticity (88%), and bladder symptoms (88%). CONCLUSIONS: A significant proportion of patients with spinal TB and severe motor deficits experience remarkable improvement after surgical decompression and hence should undergo surgery even though they may be suffering from paraplegia of considerable duration.