Petroclival Meningioma: Management Strategy and Results in 21st Century

Background

Petroclival meningioma (PCM) is considered among the most difficult tumors to be treated by microneurosurgery because of its location and its relation to critical structures. The authors report on the outcome in a series of patients with PCM treated in the new millennium with a tailored approach of gross total excision or subtotal removal and adjuvant Gamma Knife Radiosurgery (GKR) depending on the particular case.

Methods

Between 2001 and 2017, 72 consecutive PCMs were operated in a single center by the senior surgeon. Clinical presentation, operative approaches, intraoperative findings, complications, and imaging findings were retrospectively analyzed. Postoperative outcome, adjuvant Gamma knife, and follow-up findings were reviewed.

Results

The average age was 47.95 years, and female-to-male ratio was 52:20. Cavernous sinus extension was present in 21 patients. The mean duration of follow-up was 66.65 months. Gross-total resection, near-total resection (NTR), and subtotal resection (STR) resection was achieved in 30, 24, and 18 (42.8%, 34.28%, and 25%) patients, respectively, with recurrences of 10%, 33%, and 50%, respectively. Twenty-two patients (18 STR and 4 NTR) had received postoperative GKR. Only four patients had recurrences following GKR. New cranial nerve deficits were more common in patients in whom a total resection was performed. There was no mortality.

Conclusions

Gross total excision had the best recurrence free rate though with a higher morbidity. Upfront GKR is advisable in patients with residual tumor, if the preoperative temporal course had a rapid symptomatology, to reduce recurrence. Wait and watch for a small intracavernous residue and radiosurgery on growth is also a valid option as long as follow-up is not suspect. A flexible approach of individualizing the treatment protocol for a given patient goes a long way toward optimal outcome.

Protocol-Based Early Decompressive Craniectomy in a Resource-Constrained Environment: A Tertiary Care Hospital Experience

Objectives:

Decompressive craniectomy (DC) is an emergency life-saving procedure used to treat refractory intracranial hypertension (RICH). The authors aim to analyze their experience with protocol-based early DC (<24 h) in RICH cases diagnosed based on clinical and radiological evidence, without preoperative intracranial pressure monitoring done over 10 years.

Materials and Methods:

This is a retrospective, observational study which includes 58 consecutive patients who underwent protocol-based early DC by the senior author at a single institution between 2007 and 2017. Background variables and outcome in the form of Glasgow Outcome Score-Extended (GOS-E) at 6 months and 1 year were analyzed.

Results:

Fourteen patients had traumatic brain injury (TBI), 17 had intracranial hemorrhage (ICH), 14 had malignant cerebral infarcts (MCI), and the reminder 13 patients had other causes. At 6 months, the mortality rate was 22.4%. Good recovery, moderate disability, and severe disability were seen in 13.8%, 17.2%, and 43.1% of patients, respectively. Two patients were in vegetative state. The cutoff for favorable/unfavorable outcome was defined as GOS-E 4–8/1–3. By this application, 63.8% of patients had favorable outcome at 6 months. The favorable outcome in patients of TBI, ICH, and MCI was 57.1%, 58.8%, and 85.7%, respectively.

Conclusions:

DC helps in obtaining a favorable outcome in selected patients with a defined pathology. The diagnosis of RICH based on clinical and radiological parameters, and protocol-based early DC, is reasonably justified as the way forward for resource-constrained environments. The risk of vegetative state is small.

Microsurgery of Vestibular Schwannoma Post-radiosurgery

Objectives

Microsurgery of vestibular schwannoma (VS) after radiosurgery is not common. In this study, we analyze nerve functional outcomes and technical challenges associated with the microsurgery following radiosurgery of VS.

Materials and Methods

Sixteen patients underwent microsurgery at an average of 37 months (range 3-96 months) after radiosurgery. Indications of surgery included tumour progression or clinical worsening. Twelve of them had never undergone microsurgery before radiosurgery, and three had partial excision before radiosurgery. Maximum tumour diameter of all patients ranged from 23 to 51 mm, of which four were giant tumours. Operative findings and post-microsurgery clinical course, imaging and outcome were analysed.

Results

The tumours found at surgery were firmer, with an avascular core but increased vascularity near the surface. There were thickened arachnoid and often adhesions with surrounding structures making total excision difficult. Near total excision was employed in such cases. Eleven patients underwent gross total/near total resection. No major morbidity or death was reported. Post-surgery, eight patients had grade I/II HB facial function, four had grades III and three had grades IV/V. Of the last three, two had the same deficit preoperatively. At the last follow-up (average 50 months), all patients had a stable facial function. None of the patients have undergone any further radiosurgery/microsurgery since the last intervention.

Conclusion

For the few patients who require microsurgery after radiosurgery, excellent tumour resection with an acceptable outcome can be achieved with proper techniques and neuromonitoring. Leaving tiny residue attached to critical structures is the key to an optimal outcome.

Nonvestibular Schwannoma Tumors in the Cerebellopontine Angle: A Single-Surgeon Experience

Background:

The most common cerebellopontine angle (CPA) tumor is a vestibular schwannoma. Schwannomas account for 8.5% of all intracranial tumors and more than 90% of the tumors originate from the eighth cranial nerve, but one in five CPA tumors are not vestibular schwannoma. These tumors may have different manifestations and require different management strategies.

Methods:

We report 224 consecutive NVCPAT operated in the Department of Neurosurgery, P.D. Hinduja National Hospital and Medical Research Centre, Mumbai, by the senior author between 2001 and 2014 and discuss the different approaches and outcomes in NVCPAT.

Results:

The age range was 20–60 years and there were 129 females and 95 male patients. The clinical material consisted of 81 cases of meningioma (36.1%), 44 cases of epidermoid (19.64%), 34 cases of trigeminal schwannoma (15.17%), 26 cases of jugular foramen schwannoma (11.60%), and 39 cases of other tumors (17.41%). In nonvestibular schwannoma (NVS), symptoms and signs from cranial nerve VIII are less frequent and other cranial nerves and cerebellar symptoms and signs predominate.

Conclusion:

Symptoms and signs are different in NVCPAT from those found in patients with vestibular schwannoma. Hearing loss is not the predominant symptoms. Cerebellar signs and trigeminal dysfunction are more common. The most common approach used in the current series was retrosigmoid craniotomy. Gamma knife radiosurgery was a useful adjunct in a subset of these patients.

Pineal region cavernoma--case report

A 45-year-old male presented with a rare pineal region cavernoma. Magnetic resonance (MR) imaging confirmed the preoperative diagnosis. The tumor was totally excised. The patient was subsequently cured. Analysis of 15 reported cases found a slight female preponderance. The second and third decades were the most common age group. The course of pineal cavernomas can be complicated by hemorrhage, occlusion of cerebrospinal fluid pathways, and focal neurological and neuroendocrine symptoms but no specific clinical features. However, MR imaging has high sensitivity and the specificity for the diagnosis of pineal cavernoma. Total microneurosurgical excision is the treatment of choice, and patients had an excellent outcome. Stereotactic biopsy can be potentially dangerous because of the risk of hemorrhage. The use of radiosurgery requires evaluation of long-term risks and safe dose levels. Total excision of the pineal cavernoma using microsurgical techniques is the choice of treatment in young and healthy patients since there is an increased risk of recurrent hemorrhage and progressive neurological decline. A conservative approach is preferred in older patients.

Gamma-knife radiosurgery for trigeminal neuralgia

Gamma knife was installed at the PD Hinduja National Hospital and Medical Research Centre, Mumbai, India, in January 1997. In the first year of gamma-knife radiosurgery to January 1998, we treated 110 patients, of whom six had medically refractory trigeminal neuralgia. Seven treatments were administered to this group of six patients (one had bilateral neuralgia). This report evaluates the effectiveness of radiosurgery treatment in these patients. The median age of the patients was 56 years and there were five males and one female. Following Leksell stereotactic frame fixation, a magnetic resonance imaging scan was done in all. The Leksell gamma plan was used for planning. A radiosurgery dose of 70-80 Gy was delivered to the trigeminal root entry zone, 2-4 mm anterior to the junction of the pons and trigeminal nerve with a single 4 mm collimator helmet. Complete pain relief was achieved in four patients. Two had partial relief. No patient developed any radiosurgery related morbidity during the follow-up period of 5-16 months. Radiosurgery seems to be an effective approach for medically or surgically refractory trigeminal neuralgia.

Granular cell tumour (choristoma) of the neurohypophysis--a report of two cases

Granular cell tumours of the neurohypophysis are uncommon and only 30 cases are documented in the literature till 1994. In this communication, the salient clinical and histomorphological features in two patients with granular-cell tumour of the neurohypophysis are described.

Dysembryoplastic neuroepithelial tumour of the central nervous system--a case report

Dysembryoplastic neuroepithelial tumour (DNT) of the central nervous system is a recently recognized entity. We describe the clinical and characteristic histomorphological features in a patient with DNT. As this lesion carries a favourable prognosis, it becomes essential to make an accurate histopathological diagnosis.

Gliomatosis cerebri--a case report

Gliomatosis cerebri is a vary rare neoplastic lesion of the central nervous system. An intra-vitam diagnosis of gliomatosis cerebri can be suggested with a steleolactic biopsy of the lesion in conjunction with Magnetic Resonance Imaging (MRI) findings in the brain.

Central nervous system ganglioglioma. A clinicopathologic study

Gangliogliomas are one of the uncommon tumours of central nervous system. Since these tumours have been associated with an indolent clinical course and benign biological behaviour, it is essential to make an accurate histopathological diagnosis of ganglioglioma. In this study the salient clinical and histopathological features in six patients with intracranial ganglioglioma are described.

Craniospinal and spinal enterogenous cysts--report of three cases

We report three cases of enterogenous cyst, one craniospinal and two spinal manifesting with features of spinal cord compression. In one the cyst was intramedullary in location and in the other two it was intradural, extramedullary. The unusual clinical presentation, location and magnetic resonance imaging (MRI) characteristics are discussed. None of the three patients had any vertebral anomaly or other congenital malformation. All patients had excellent outcome following surgery.

Spontaneous haemorrhage in acoustic neurinomas

Gross intratumoural haemorrhage in acoustic neurinoma is rare. The authors describe seven patients, out of a consecutive 99 cases of acoustic neurinoma operated by the first author, who presented with haemorrhage. Risk factors for haemorrhage appear to be large size, mixed Antoni type and secondary vascular changes.

Nucleolar organizer regions in pituitary adenomas

In this study, thirty-two non-functional and eighteen functional pituitary adenomas were analysed for the presence of argyrophilic nucleolar organizer regions (Ag-NORs) in paraffin sections, using an one-step silver-colloidal staining method. Differences in the mean Ag-NOR numbers of functional pituitary adenomas were statistically significant than those of non-functional pituitary adenomas. It is being emphasised that evaluation of Ag-NOR count is a more reliable index than the presence of mitotic figures in predicting the proliferative activity as well as possibility of recurrence in a patient with pituitary adenoma.

Intraventricular neurocytoma: a report of two cases

Central neurocytomas are uncommon intracranial neoplasms. More than one hundred cases are documentated in the literature. In this report we describe the clinical and histopathological features in two patients with intraventricular neurocytoma. As the light microscopic features of neurocytoma resemble with that of an oligodendroglioma, it is essential to differentiate these two tumours, using either ultrastructural or immunohistochemical techniques.

Nodular inflammatory mass of the dura mimicking a meningioma--a report of two cases

Histopathological examination of surgical specimens in two patients with an operative diagnosis of meningioma, revealed the presence of dense nodular aggregation of lymphocytes, plasma cells and conspicious absence of meningothelial components. Possibilities of lymphoreticular malignancy, myeloproliferative disorders and other causes for various inflammatory diseases were excluded by appropriate investigation in these two patients. Pathogenesis of this localised lymphocyte-plasma cell aggreation in the dura manifesting as a space-occupying lesion could not be defined in these two patients. It is emphasised that this benign lesion should be recognised as well as distinguished from secondary lymphomatous deposits and solitary plasmacytoma of the dura.

Primary Ewing's sarcoma of the base of skull: a case report

Primary cranial Ewing's sarcoma is an exceptionally rare lesion and only eleven cases have so far been reported. In this report we describe a case of primary Ewing's sarcoma arising from the floor of middle cranial fossa. Salient clinical, neuroradiological and light microscopic features in this case are described. A brief review of earlier published cases of primary cranial Ewing's sarcoma are also presented.

Transcallosal approach to anterior and mid-third ventricular tumors--a review of 62 cases

Sixty-two consecutive patients with anterior and mid-third ventricular lesions were operated on by a limited anterior transcallosal approach from 1987 to 1992. Fifty-six cases were operated on by B K M. Following lateral ventricular entry, transforaminal route to the third ventricle was preferred and utilised in 44 cases. An interfornicial or subchoroidal approach was employed only if transforminal entry was not adequate and was the route in 16 and two cases respectively. Enlargement of the foramen of Monro by incising its margins was not resorted to in any case. The age of the patients ranged from six to 64 years, (mean 29 years). Males were twice as often affected as females. There were 50 benign lesions: 43 colloid cysts, two craniopharyngiomas, one arachnoid cyst and four cysts of uncertain histology, and 12 malignant tumours: eight intrinsic astrocytomas, two oligodendrogliomas, one ependymoma and one primary lymphoma. The outcome in the benign cases was excellent in 42, good in six and poor in one. There was one post-operative death due to meningitis.

Primary lymphoma of the brain

In this study, clinical and histopathological features of primary lymphomas of the brain have been described in eight patients. The primary nature of lymphoma in these patients was confirmed by extensive clinical as well as radiological investigations and supported by a detailed histopathological examination. Computerised tomography (CT) scan showed multiple intra-cerebral lesion in two patients and in six patients the lesion was solitary. Although primary lymphoma of the brain carries poor prognosis, it is essential that these tumours should be accurately diagnosed as well as should be distinguished from secondary tumours.

Pleomorphic xanthoastrocytoma. Report of four cases

Four cases of pleomorphic xanthoastrocytoma (PXA), a low-grade leptomeningeal glioma with a reported favorable prognosis affecting young patients, are reported together with a discussion and review of management and prognosis. A literature review has confirmed a favorable prognosis in at least 50% of patients with this disorder. Seventeen of 35 reported patients are still alive and often seizure-free for a mean period of 7.4 years (range 2 to 18 years) after diagnosis. Five patients have died within 2 years and four between 9 and 25 years after diagnosis of PXA. In some cases in which death followed shortly after diagnosis, there may have been histological confusion between PXA and a malignant glioma with heavily lipidized tumor cells. Nonetheless, transformation of PXA into a malignant astrocytoma or glioblastoma with eventual death may occur many years after initial diagnosis. From the currently reported cases it does not appear possible on clinicopathological grounds to predict which patients will have a favorable prognosis. Optimal management of PXA seems to be primary surgical resection with later surgery for residual or recurrent tumor. The role of radiotherapy in the management of PXA is at this time uncertain.

De novo saccular aneurysms

The authors report two patients with aneurysmal subarachnoid hemorrhage in whom carotid arteriography revealed aneurysms that had developed at previously normal locations and from infundibula during the years since initial angiography. Neither of these patients had congenital anomalies of the cerebral circulation and, apart from smoking in excess of 30 cigarettes a day, there were no common clinical features. The role of congenital and environmental factors in the formation of aneurysms and the enlargement of infundibula are reviewed.

Multicentric glioma presenting with hemorrhage

We report a case of multicentric malignant astrocytoma occurring simultaneously in both cerebrum and cerebellum, presenting with hemorrhage into the cerebellar tumor. Hemorrhage into a cerebellar glioma in an adult is very rare. None of the cases of multicentric glioma described in the literature presented with intratumoral hemorrhage. This combination in our patient has prompted us to report this case and to reaffirm the need to consider the diagnosis of malignant glioma in patients with multiple intracranial tumors.

Tension pneumocephalus following nasal polypectomy

Subdural tension pneumocephalus in a 80-year-old man following nasal polypectomy, presenting clinically with progressive weakness of both legs, is reported and the pathogenesis is discussed. The diagnosis of tension pneumocephalus and the options of management are considered.

Extracerebral hematoma in association with dural substitute

The authors present a patient who developed an acute hemorrhage around a Silastic dural substitute 13 weeks after excision of a meningioma and implantation of the graft. The relevant literature is reviewed.

Heterotopic brain cyst from middle cranial fossa to submandibular region

The case of a newborn boy with a congenital cystic neck mass causing respiratory distress is reported. This lesion extended from the submandibular region through a bone defect to the middle cranial fossa but remained totally extradural. There was no underlying brain abnormality. The cyst was composed mainly of mature neuroglial tissue, with some ependymal and choroid plexus elements, and was diagnosed as heterotopic brain. After 8 years' follow-up, the child still has no deficits.

Haematemesis from distal extracranial carotid aneurysms. Case report and literature review

A 5-year-old white boy presented with life-threatening haematemesis from spontaneous rupture of an aneurysm of the high cervical internal carotid artery (ICA). The haemorrhage was controlled by emergency trap ligation of the distal ICA in the neck. The child made an excellent recovery and 7 years later has no neurologic deficit other than an Horner's syndrome. The diagnosis of an extracranial carotid artery aneurysm without a pulsatile lump may be very deceptive.