Nontraumatic Subdural Hematoma and Intracystic Hemorrhage Associated with a Middle Fossa Arachnoid Cyst.

Intracranial arachnoid cysts (ACs) are relatively common findings that can be seen in up to 2% of patients. They are generally found incidentally with a benign clinical course and can be usually managed by observation. We report an unusual case of a middle fossa AC presenting with spontaneous intracystic hemorrhage along with subdural hematoma (SDH) causing significant mass effect and midline shift requiring surgical treatment. Even though the risk of hemorrhage in patients with AC is very low, the presence of AC is a known risk factor for SDH. Fortunately, the clinical outcome of patients who present with hemorrhage associated with AC is generally favorable with early recognition and prompt surgical treatment. Our case highlights the fact that both intracystic hemorrhage and SDH can occur in association with AC even in the absence of trauma and should be kept in mind when counseling patients with incidental AC about the natural history of these lesions.

Hypertrophic posterior arch of atlas causing cervical myelopathy.

Cervical stenosis, especially of the upper cervical spine, is quite rare which can be developmental or acquired. Clefts or aplasias of anterior and posterior arches of atlas, ossification of the transverse atlantal ligament, hypertrophy of the dens and os odontoideum are rare conditions causing cervical myelopathy reported either singly or in combination. Hypertrophy of the posterior arch of atlas in the absence of any ring hypoplasia as a cause of cervical myelopathy has not been reported earlier. The authors report a case of cervical myelopathy in a 26-year-old female due to hypertrophied posterior arch of atlas which was preoperatively diagnosed as a bony tumor. Being aware of such an entity may avoid diagnostic surprises and facilitate patient prognostication and management.

Factors affecting the development of hypothalamus and pituitary lesions in fatal closed head injury: a prospective study.

OBJECTIVES: To determine the factors affecting the development of pituitary and hypothalamic lesions after fatal closed head injury. MATERIALS: Thirty-four patients with severe closed head injury succumbing to the effects of brain trauma before or during admission, whether managed conservatively or surgically, formed the study group. Clinical parameters, injury to death interval, radiologic data, and management details were taken into consideration. Autopsy was performed within 48 hours of death; hypothalamus and pituitary were carefully removed and evaluated for the presence of lesions on hematoxylin and eosin and immunohistochemical staining. RESULTS: Patients were categorized into early death group (n = 11, those succumbing before/on admission) and late death group (n = 23, those succumbing after admission). Histopathologic evaluation of pituitary revealed capsular hemorrhages in 50%, posterior pituitary hemorrhage in 25%, anterior pituitary infarct in 21.8%, and anterior pituitary hemorrhage in 6.2% patients. Hypothalamic hemorrhage was observed in 65.2% patients and infarcts in 17.3%. Lesions in hypothalamus and pituitary were significantly related to the presence of ventricular compression on computed tomography scan and survival of >24 hours after injury (p < 0.05). Capsular hemorrhage, anterior pituitary hemorrhage, and posterior pituitary hemorrhage were present in 40%, 10%, and 30% of the patients in the early death group when compared with 54.5%, 4.5%, and 22.7% of the patients in the late death group. Anterior pituitary infarcts were present in 10% of the patients with early deaths and 27.3% patients in the late death group. Hypothalamic hemorrhages were present in 44.4% of patients in early death and 78.6% in late death groups. Hypothalamic infarcts (40%) were present in the late death group only. Two patients (25%) in the early death group and 11 (84.6%) in the late death group had lesions in pituitary as well as hypothalamus (p < 0.05). CONCLUSIONS: Presence of ventricular compression on computed tomography scan and survival >24 hours after severe head injury has a significant correlation with the development of hypothalamic and pituitary lesions. Secondary insults account for a proportion of pituitary and hypothalamic lesions after trauma, which may be amenable to prevention by early intervention to treat raised intracranial pressure (ICP)/herniation.

Assessment of endocrine abnormalities in severe traumatic brain injury: a prospective study.

OBJECTIVE: The frequency and pattern of endocrine abnormalities among patients with traumatic brain injury have been the subject matter of very few studies. This study was intended to assess the pattern of endocrine dysfunction following severe head injury. METHODS: Severe head injury patients admitted to the Department of Neurosurgery, All India Institute of Medical Sciences, New Delhi, from January to December in 1 year formed the study group. Apart from clinical assessment, NCCT of the head was performed on all patients on admission. A complete anterior pituitary hormone analysis was performed within 24 h of injury and was repeated at 2 weeks, 3 months and 6 months amongst patients who survived. RESULTS: A total of 99 patients were included in the study. Forty of our patients succumbed in the hospital. Rest of the patients were followed up for 6 months. Elevations of cortisol followed by prolactin were the most common hormonal derangements at admission. Midline shift on CT scans was inversely related to cortisol elevation and directly related to GH elevation. Infarct on CT scans was inversely related to cortisol and LH elevation. A significant alteration was found in the decreasing trend of the mean T4 values and normalisation or a decreasing trend from initially elevated mean cortisol and GH levels during follow-up (p < 0.05). CONCLUSIONS: This study reveals that abnormalities in hormonal profiles appear to be relatively common in severe traumatic brain injury and fluctuate significantly over at least 6 months; there is a correlation with age and radiological findings. Performance of hormonal analysis evaluation should be considered in patients with severe brain injury so that appropriate hormonal replacement can be done to optimise the clinical outcome.

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.

Totally cystic intradural extramedullary schwannoma.

Totally cystic intradural extramedullary lesions are uncommon and form a different spectrum of conditions as compared to the commonly seen intradural extramedullary tumors. Spinal schwannomas are benign tumors arising from spinal nerve root sheaths and are the most common intradural extramedullary spinal tumors. Though cystic changes in schwannomas are well described, most spinal schwannomas are solid or heterogeneous solid tumors and a totally cystic schwannoma is uncommon. The authors describes a case of totally cystic intradural extramedullary schwannoma and stress the importance of complete contrast imaging to differentiate this rare but almost completely curable tumor from other common intradural cystic lesions of the spine.

MR imaging in aneurysmal bone cyst of the orbit.

Aneurysmal bone cyst is a benign fibro-osseous lesion usually described in the long bones. Intraorbital aneurysmal bone cyst is a rare clinical entity with an entirely different outcome and prognosis as compared to the usual pediatric orbital tumors. The authors report magnetic resonance imaging (MRI) features of an orbital mass lesion in a 4-year-old child who presented with painless proptosis of right eye. Characteristic MRI findings led to a suspicion of an aneurysmal bone cyst that was totally excised via a right frontotemporal craniotomy. Appreciation of characteristic MRI features can be of extreme help for appropriate diagnosis and management of this rare entity.

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.

Spontaneous thrombosis of giant cavernous internal carotid artery aneurysm in a neonate. Case report and review of the literature.

Neonatal intracranial aneurysms are rare, with only 20 cases being reported in the literature. No case of spontaneous resolution of a giant intracranial cavernous segment aneurysm in a neonate is reported till date. The authors describe a 3-week-old male child who presented with a left-sided tonic seizure episode and was diagnosed as having a right-sided giant cavernous internal carotid artery aneurysm. The aneurysm was found to be totally thrombosed on angiography done before planning definitive treatment. The child is doing well at 2 years of follow-up. Spontaneous thrombosis, an exceptionally rare but fortunate outcome in a rare case of giant neonatal internal carotid artery aneurysm, has led the authors to report this case. The need of repeat imaging or angiography should be considered to rule out this rare outcome, more so if there is any delay between the ictus and treatment.

Vasospasm after transsphenoidal pituitary surgery: a case report and review of the literature.

Vasospasm, so commonly described after aneurysmal rupture, is very rare after surgery for brain tumors. Its occurrence after transsphenoidal surgery is extremely uncommon with only three cases reported as per the authors' review of the literature. The authors report a case of pituitary macroadenoma in a 34-year-old female who underwent transsphenoidal tumor decompression and developed angiographically documented vasospasm during the course of her illness. The rarity of the occurrence of vasospasm after transsphenoidal surgery makes its management very challenging, frequently leading to a delay in diagnosis and a poor outcome. The key to successful management is a high index of suspicion and early proactive management.

Giant cervical pseudomeningocoele following brachial plexus trauma.

We report an unusual case of a young man with a traumatic brachial plexus injury who presented with a large right-sided neck swelling 1 month after trauma. Clinical and diagnostic evaluations revealed a giant cervical pseudomeningocoele with meningitis and hydrocephalus. Following treatment for meningitis, the patient underwent ventriculoperitoneal shunt, which produced total resolution of the pseudomeningocoele. The management is discussed.

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.