Anatomy of the occipital lobe using lateral and posterior approaches: a neuroanatomical study with a neurosurgical perspective on intraoperative brain mapping.

BACKGROUND: A major concern of occipital lobe surgery is the risk of visual field deficits. Extending anatomical occipital lobectomy to the functional requires awake conditions because the anterior resection border comprises language-, motor- and visuospatial function-related areas within the temporal and parietal lobes. This study investigated the lateral and posterior perspectives of the occipital lobe anatomy when approaching intraaxial occipital lobe lesions. MATERIALS AND METHODS: Ten adult cadaveric cerebral hemispheres were dissected after being prepared following the concept described by Klingler for the first time. RESULTS: The occipital lobe was located posteriorly to the parietotemporal line. Within the occipital lobe, the occipital horn of the lateral ventricle represented the only anatomical landmark. Laterally, optic radiation was identified as a part of the sagittal stratum. None of the intraoperatively identifiable tracts was found medial to the occipital horn. Language- and motor-related areas were identified anteriorly and should be actively identified when lobectomy based on function is planned. Subcortically, from a posterior perspective, the anterolateral border constituted the arcuate fascicle/superior longitudinal fascicle complex and was anteromedial to the thalamocortical tract. Remaining posterior to the line connecting the preoccipital notch with the superior Rolandic point avoided the cortical and white matter tracts related to language, motor and visuospatial function. CONCLUSIONS: Knowledge of occipital lobe anatomy and surrounding structures is essential to preoperatively assess the risk of the procedure and proper consultation of a patient in terms of the extent of resection, primarily concerning visual field deficits.

Surgical management of posterior petrous meningiomas.

BACKGROUND AND PURPOSE: The aim of the study is to present our experience in the surgical treatment of posterior petrous meningiomas in regard to clinical presentation, surgical anatomy, complications and long-term functional postoperative results. MATERIAL AND METHODS: A series of 48 consecutive patients operated on for posterior petrous meningiomas at the authors' institution between 2002 and 2011 is reported. The main symptom on first admission was hypoacusis, impairment of the fifth cranial nerve and cerebellar ataxia. The tumour was found to be attached to the premeatal dura in 46%, the inframeatal dura in 29% and the postmeatal dura in 25% of cases. Tumour resection was categorized as grade I in 16 patients, grade II in 29 patients, grade III in 1 patient and grade IV in 2 patients, according to the Simpson classification system. The petrosal approach and retrosigmoid approach were suitable for posterior petrous meningiomas. RESULTS: Postoperative facial nerve dysfunction appeared in 8 and further deteriorated in 2 patients. Hearing function deteriorated after surgery in 8 and improved in 2 cases. Perioperative death occurred in two patients. Tumour recurrence was observed in two patients, and both underwent a second operation and postoperative stereotactic radiotherapy. CONCLUSIONS: Surgical treatment of posterior petrous meningiomas has become increasingly safe but these tumours still remain a surgical challenge because of the relatively high incidence of permanent complications associated with their removal. The site of displacement of the cranial nerves depending on the dural origin of the tumour has the most influence on the related difficulties in its removal.

Necrotic rhabdoid meningiomas with aggressive clinical behavior.

Rhabdoid meningioma (RM) is a rare, aggressive variant of meningioma classified as a WHO Grade III malignancy. RM exhibits a striking histological resemblance to other rhabdoid tumors and strong tendency towards local recurrences, CSF dissemination, and/or remote metastasis. The majority of reported cases are of secondary rhabdoid transformation in recurrent meningiomas. We present two unusual cases of rhabdoid meningiomas diagnosed as a primary intracranial lesion in adults that were associated with extensive necrosis and an aggressive clinical course. On histological examination, the majority of the tumor mass was composed of necrotic tissue with focal clusters of neoplastic cells, often localized around blood vessels. Most tumor cells exhibited typical rhabdoid morphology with large, vesicular, often eccentrically located nuclei with distinct nucleoli and abundant cytoplasm containing eosinophilic hyaline inclusions. Classical meningothelial features with focal whorl formation were scarce and seen only in one case; in the second case the tumor was entirely rhabdoid. The differential diagnosis with atypical teratoid/rhabdoid tumors (AT/RTs) and other neoplasms, particularly metastatic carcinoma, was considered. Immunohistochemical and electron microscopic study were critical for the accurate diagnosis of the rhabdoid subtype of meningiomas. Rhabdoid cells stained diffusely positive for vimentin and S-100 protein and showed focal but strong expression of epithelial membrane antigen and cytokeratins. The rhabdoid areas of the tumors exhibited high mitotic activity with a MIB-1 labeling index of 80 - 90%. The diagnosis of rhabdoid meningioma was supported by evidence of SNF5 (INI1) protein expression. Ultrastructural examination demonstrated the presence of interdigitating cell processes joined by numerous desmosomes and paranuclear whorls of intermediate filaments typical of the rhabdoid phenotype. Our two cases of rhabdoid meningiomas were associated with lethal outcome within a few months of initial diagnosis. Extensive necrosis in rhabdoid meningioma might be considered an additional predictor of aggressive clinical behavior.

Heavily lipidized, calcified giant cell glioblastoma in an 8-year-old patient, associated with neurofibromatosis type 1 (NF1): report of a case with long-term survival.

Giant cell glioblastoma (GCG-BM) with predominance of bizarre, multinucleated giant cells is a rare subtype of glioblastoma, however, its clinical behavior and histological features are still not fully understood. We report an unusual case of a heavily lipidized form of giant cell glioma corresponding mostly to GCGBM in a young patient with neurofibromatosis 1 (NF1). Histologically, the tumor revealed numerous characteristic histopathological features of giant cell glioblastoma including cellular pleomorphism with numerous giant tumor cells, pseudopalisades around necrotic foci and mitotic activity, accompanied by additional unique morphological elements such as massive lipidization of the neoplastic cells, abundant microcalcifications and angiomatous pattern of vascularization. Such aberrant morphology might be associated with the unusually long survival period of 12 years without clinical evidence of tumor recurrence. The coexistence of intracerebral heavily lipidized, calcified giant cell glioblastoma with NF1 has not been previously reported in literature.

Pedunculated subependymomas of lateral ventricle.

The authors describe two cases of extremely rare, pedunculated subependymomas of lateral ventricle. One patient presented with symptoms of intracranial hypertension (case 2); CT scan revealed evidence of intraventricular mass, but in second patient (case 1) coexisting symptomatic anaplastic astrocytoma masked on CT-scan the presence of asymptomatic intraventricular tumour, which was found no earlier than at autopsy. The cellular origin of this rare intracranial neoplasm is discussed.

[Primary brain lymphomas]. / Pierwotne chloniaki mózgowia.

In the Department of Neurosurgery of the Medical University of Warsaw 11 patients with primary central nervous system lymphomas were diagnosed and treated between 1990 and 1999. The patients comprised of 6 females and 5 males, aged 23 to 86 years, with most patients presenting in the sixth decade. The time from first symptoms to the diagnosis ranged from a few days to 5 months. In the majority of patients, the leading symptoms were: headaches, motor weakness, aphasia and memory disturbance. Initial diagnosis was based on MR in 3 patients, CT in 7 and on both CT and MR in 1 patient. The frontal lobe was the most common site of involvement. All the patients underwent surgery. The histological diagnosis was confirmed by immunohistochemical analysis using monoclonal antibodies: CD 20, CD3, CKMNF 116. In all cases, a B-cell type lymphoma was diagnosed. Radiotherapy was administered to 4 patients, 2 received chemotherapy and 1 received combined treatment. The median survival time so far is 17.6 months.

Epithelioid schwannomas of the acoustic nerve.

Epithelioid schwannomas occur predominantly in relation to peripheral nerves and are associated with histological and clinical malignancy. However, a variant of the epithelioid schwannoma involving cranial nerves is extremely rare. In this study we report three cases of epithelioid schwannomas originating from the acoustic nerves and located in the cerebello-pontine angles. In the first case, the tumor was histopathologically entirely solid and demonstrated biphasic pattern with both spindle-shaped cells and a population of round or polygonal epithelioid cells. The second one consisted of the smaller part exhibiting typical Antoni B and A tissue and large areas containing clusters and bundles of epithelioid cells. Purely epithelioid schwannoma composed predominantly of cords or nests of round and polygonal epithelioid cells were observed in the third case. All schwannomas revealed marked polymorphism and nuclear hyperchromasia. Immunohistochemical studies showed a diffuse, strong positivity for S-100 protein in the cytoplasm of the spindle and epithelioid tumor cells. These two populations of cells were positively stained for vimentin, but were negative for EMA, cytokeratin and HMB45. Patchy GFAP-immunoreactivity was also noticed at the peripheral parts of the tumors. The authors discuss differential diagnosis of this unusual variant of schwannoma in relation to malignant transformation of the epithelioid component.

Intrasellar neuronal hamartoma associated with pituitary adenoma. Case report.

46-year-old acromegalic women presenting high level of growth hormone (32 ng/ml) in the serum underwent surgery. The intrasellar tumor, 16 mm in diameter, has been removed. The biopsy material consisted of two types of closely adjacent and intermingled tissues, one of which was growth hormone positive acidophilic adenoma, the second component were haphazardly oriented ganglion cells of various size and shape, also multinuclear, with bundles of unmyelinated fibers. The cytoplasm and processes of ganglion cells were immunopositive for neurofilaments and for synaptophysin on cellular membranes and processes. There were none glial fibrillary acidic protein positive cellular elements. The authors discuss commonly used name of choristoma for this type of tumor and the problem of possible neurosecretory stimulation of pituitary adenoma by neuronal hamartoma.

[Surgical outcome of temporal lobe epilepsy]. / Wyniki operacyjnego leczenia padaczki skroniowej.

Results of the surgical treatment of temporal lobe epilepsy--Authors present their own experience in the surgical treatment of temporal lobe epilepsy. 403 patients were operated upon. The age of the patients was not limited. The beginning of the epilepsy was in most cases in early childhood, however the conservative treatment was continued for a very long time, usually over 10 years. The modern diagnostic tools, especially MRI, make it possible to diagnose the temporal epileptic focus more often, than previously, especially in cases with morphological substrate. Temporal lobectomy with amygdalo-hippocampectomy was performed. The follow-up was at least 3 years after surgery. Outs of 343 patients examined in this period 175 were cured, without seizures after surgery. Next 61 patients had no more than 2 small attacks a year. So in 69% of patients the result was very good or satisfactory. The neuropsychological investigation revealed that in most patients the IQ improved. Their quality of life improved markedly according to their own opinion.

[A case of congenital fissure of C2 and C3 arches with compression of cervical spinal cord]. / Opis przypadku wady wrodzonej niespojenia luków kregu C2 i C3 z uciskiem na rdzen kregowy w odcinku szyjnym.

A 41-years old male patient is reported who had spastic paresis of all extremities, and evidence of peripheral motor neuron damage. He had been treated with steroids for 10 years after erroneous diagnosis of multiple sclerosis. The final diagnosis was a congenital fissure of C2 and C3 arches with spinal cord compression in cervical part. After operation some improvement of the neurological status was obtained.

[Surgical treatment of comatose patients after aneurysmal subarachnoid hemorrhage]. / Leczenie operacyjne chorych w stanie spiaczki po krwotoku z tetniaka wewnatrzczaskowego.

The author presents a series of 40 patients in coma after aneurysmal SAH treated between 1984 and 1994. The level of consciousness of those patients ranged between 3 and 9 points, graded according Glasgow Coma Scale. Eighteen patients were admitted within 72 hours after initial bleeding, five between 4-7 days after hemorrhage and in seventeen coma occurred due to rebleeding. Computerized tomography revealed only subarachnoid bleeding in 7 patients; eleven patients had massive intraventricular bleeding with consecutive enlargement of ventricles in 5. In 22 patients, subarachnoid hemorrhage with large intracerebral hematoma was found. In 5 patients with haematocephalus and in 4 with intraventricular bleeding, ventricular drainage was performed after admission. Post-drainage improvement of the comatose state occurred in 3 patients only and aneurysm was clipped later; two of them were cured and one died due to infectious complication. Six patients with intraventricular bleeding remained unchanged despite drainage and died in the early period after operation. Nineteen patients with intracerebral haematoma were operated on. In 10 of them surgery was limited to evacuation of the haematoma only and in 9 removing of haematoma and clipping of aneurysm were performed. Thirteen, operated on patients with intracerebral haematoma died and six survived. Twelve patients were not operated on. All of them died, most often due to rebleeding. Among 28 patients admitted in coma after aneurysmal haemorrhage and who were operated on as "the last chance for the patient" 20 died and 8 (28.6%) survived; 3 of them recovered completely or nearly completely, 4 were severed disabled and one remained in vegetative state.

[Non-traumatic nasal cerebrospinal rhinorrhea]. / Nieurazowe plynotoki nosowe.

Non-traumatic rhinorrhoea of CSF occurs much less frequently than traumatic ones. The most frequent causes of this rhinorrhoea are congenital abnormalities of the cranial bass. Non-traumatic rhinorrhoea with normal cerebrospinal fluid pressure and those with raised CSF pressure are known. In the latter rhinorrhoea is one of the signs of a disease causing CSF pressure rise. In view of the rare occurrence of nontraumatic rhinorrhoea 6 cases are reported which were treated in the years 1986-1993 in the Neurosurgery Department, Medical Academy in Warsaw.

[Antigravity suit used for neurosurgical operations in sitting position]. / Zastosowanie lotniczego ubioru przeciwprzeciazeniowego w operacjach neurochirurgicznych w pozycji siedzacej.

The aviator's antigravity suit (G-suit) was used for 40 operations on neurosurgical patients operated on in sitting position. The G-suit was filled with air to 0.2 atmosphere (20 kPa) pressure in 26 cases, and 0.3 atm. (30 kPa) in 14 cases. In all cases G-suit filling was followed by central venous pressure rise and mean arterial pressure rise. Venous air embolism was found in 5 (12.5%) patients. No other complications connected with the use of G-suit were observed.

[Surgical treatment of meningiomas of medial part of sphenoid ala and en-plaque meningiomas of perisellar area]. / Operacyjne leczenie oponiaków przysrodkowej czesci skrzydla kosci klinowej i oponiaków en-plaque okolicy okolosiodlowej.

The authors present some clinical aspects of their own experience in the operative treatment of clinoidal and en-plaque suprasellar meningiomas which account for 5.6% of all intracranial meningiomas in Department of Neurosurgery treated in the years 1987-93. Visual loss was the first symptom of disease. In conclusion, the authors stress the still unacceptably long period between the onset of symptoms and correct diagnosis. Possibilities of total removal are limited by the size of tumour and compression of adjacent structures, and the chance for visual improvement is low for that reasons. Visual improvement was observed in only one case after surgery, however in 5 cases worsening of visual acuity was noted in postoperative period. Mortality rate was 6.2%. Adjuvant radiotherapy was performed in non patient. Long term results in ophthalmological and neurological aspects are discussed.

[Meningiomas of sella turcica: some clinical aspects]. / Oponiaki guzka siodla tureckiego--wybrane aspekty kliniczne.

The authors present their own experience in the treatment of tuberculum sellae meningiomas. The presented series includes 14 patients operated on during past 7 years. Visual loss was the first symptom in 78% of patients. The period between the onset of symptom and surgical treatment was long and in the majority of patients exceeded 2 years. Monocular blindness was found in 71% of cases prior to surgery. The authors present the results of surgical treatment with special attention directed to visual function after surgery. In conclusion, the authors stress the still unacceptably long period between the onset of symptoms and correct diagnosis. When the size of tumour exceeds 4 cm and compressing of adjacent important neurovascular structures is evident, possibilities of total removal are limited and the chance for visual improvement is low.

[Surgical treatment of brain tumors and intracarnial aneurysms in patients over 70 years]. / Operacje guzów mózgu i tetniaków u chorych powyzej 70 roku zycia.

Problem of surgical treatment in the elderly is still discussed in the literature. This group of patients needs especially clear criteria of qualification for extensive intracranial procedures. The authors present their own experience with 35 patients over 70 years old with intracranial tumours and intracranial aneurysms treated in Department of Neurosurgery, Warsaw Medical School between 1992-1993. Among 11 patients treated conservatively, only 3 patients were in poor physical state with functional limitation which was a contraindication for surgery. Postoperative mortality was 4.2%. On the basis of our experience we think that patients over 70 years can be safely operated on intracranial lesions and the age is not a contraindication for neurosurgical procedures.