Fabio Roberti

Posterior fossa meningiomas: surgical experience in 161 cases.

BACKGROUNDnWe report the clinical, radiological, and surgical findings of patients with posterior fossa meningiomas surgically treated at our institution over the last 6 years.nnnMETHODSnWe reviewed 161 consecutive cases of posterior fossa meningiomas operated on between April 1993 and April 1999 at The George Washington University Medical Center.nnnRESULTSnThere were 128 female and 33 male patients (mean age 47 years, range of 10-81 years). Meningiomas were classified as petroclival (110 cases), foramen magnum (21 cases), cerebellar hemispheric, lateral tentorial (14 cases), cerebellopontine angle (9 cases), and jugular foramen (7 cases). Mean tumor equivalent diameter (TED) = (D1xD2xDE)(1/3) was 3.1 cm (range of 0.53-8.95). Head pain (50% of cases) and disturbance of gait (44%) were the most common presenting symptoms, and cranial neuropathies the most common neurological signs on admission. Mean preoperative performance status (Karnofsky scale) was 80.2 (range 40-100). Surgical approaches to these tumors included partial labyrinthectomy petrous apicectomy, fronto-temporal/fronto-temporal orbitozygomatic osteotomy, retrosigmoidal, extreme lateral, transpetrosal, and combined. In 38 cases a staged procedure was performed. Gross-total resection was achieved in 57% of patients, and subtotal/partial in 43%. Surgical mortality was 2.5% and complications were encountered in 41% of patients. Postoperative CSF leak occurred in 22 cases (13.6%). The mean follow-up was 19 months, ranging from 0.2 to 63.6, and the mean performance status of patients with a follow-up of at least 12 months was 77 (range of 40-100). Recurrence or progression of disease was found in 13.7% of cases (follow-up 2 years or more).nnnCONCLUSIONnOur experience suggests that although posterior fossa meningiomas represent a continuing challenge for contemporary neurosurgeons, such tumors may be completely or subtotally removed with low rate of mortality and acceptable morbidity, allowing most of these patients to achieve a good outcome in a long-term follow-up.

Spontaneous encephaloceles of the temporal lobe

Encephaloceles are pathological herniations of brain parenchyma through congenital or acquired osseus-dural defects of the skull base or cranial vault. Although encephaloceles are known as rare conditions, several surgical reports and clinical series focusing on spontaneous encephaloceles of the temporal lobe may be found in the otological, maxillofacial, radiological, and neurosurgical literature. A variety of symptoms such as occult or symptomatic CSF fistulas, recurrent meningitis, middle ear effusions or infections, conductive hearing loss, and medically intractable epilepsy have been described in patients harboring spontaneous encephaloceles of middle cranial fossa origin. Both open procedures and endoscopic techniques have been advocated for the treatment of such conditions. The authors discuss the pathogenesis, diagnostic assessment, and therapeutic management of spontaneous temporal lobe encephaloceles. Although diagnosis and treatment may differ on a case-by-case basis, review of the available literature suggests that spontaneous encephaloceles of middle cranial fossa origin are a more common pathology than previously believed. In particular, spontaneous cases of posteroinferior encephaloceles involving the tegmen tympani and the middle ear have been very well described in the medical literature.

The pterygopalatine fossa: an anatomic report.

The pterygopalatine fossa (PPF) is a small anatomic region of particular interest in cranial base surgery. Infectious diseases and malignancy may spread through the PPF to contiguous areas as a result of the low resistance offered by the numerous foramina and fissures that surrounds the fossa. We present an anatomic report on the PPF. Twelve sides of six fixed cadaveric heads were dissected through a LeFort I maxillary osteotomy with transantral exposure of the neurovascular content of the PPF. Arterial vascular patterns of the maxillary artery were observed. The pterygopalatine fossa is a deeply located small anatomic region with a rich neurovascular content. The third portion of the maxillary artery in the PPF may demonstrate a variable vascular morphology. A correct understanding and knowledge of the anatomic structures lodged into the PPF, as well as their relationships and functions, remain crucial to minimizing postsurgical morbidity and intraoperative complications.

Tailored anteromedial lobectomy in the treatment of refractory epilepsy of the temporal lobe: long term surgical outcome and predictive factors.

OBJECTIVEnTo analyze long-term results and to determine prognostic factors on seizure outcome in a series of patients with temporal lobe epilepsy (TLE) who underwent anteromedial temporal lobectomy (AMTL).nnnMATERIALS AND METHODSnFrom 1995 to 1998 forty-two patients suffering from non-lesional TLE underwent tailored AMTL at our Institution. We retrospectively reviewed surgical results and calculated predictive factors of good outcome in the long term.nnnRESULTSnSixty-four percent of patients were rendered seizure free (median follow up 60 months). Eleven cases (26.2%) had a significant reduction of disabling epileptic episodes. Poor seizure control was observed in four patients (9.5%). Overall surgical morbidity was 4.7%. Medial temporal sclerosis (MTS) was the most common histopathological finding (69% of cases). The presence of unilateral hippocampal abnormalities on qualitative MRI was significantly associated with excellent postoperative outcome (p<0.011). Qualitative preoperative MRI had a positive predictive value of 83% in detecting both MTS at pathological examination and excellent outcome.nnnCONCLUSIONSnTailored AMTL is a safe and effective procedure in the treatment of selected patients with medically refractory TLE. Data from preoperative qualitative MRI well correlated with histopathological findings. The presence of unilateral hippocampal atrophy on qualitative MRI was predictive of excellent outcome in the long-term follow up.

Fourth ventricular chordoid meningioma

The chordoid variant of meningioma is a histological subtype which carries with it a more aggressive clinical course and a propensity for recurrence. Similar to other meningioma subtypes, this lesion is encountered typically in the supratentorial compartment, often along the cerebral convexities. The chordoid meningioma subtype is found primarily in the adult population, and may occasionally be associated with the systemic manifestations of Castlemans disease. We present an adult patient with a rare chordoid meningioma located within the fourth ventricle. This lesion was treated with gross total resection. Chordoid meningioma must be considered within the differential diagnosis of intraventricular tumors. This histological subtype of meningioma warrants close follow-up. The patient must also be evaluated for systemic manifestations of Castlemans disease.

Rapid Improvement of Cranial Neuropathies after Endoscopic Resection of Sphenoid Sinus Mucocele

Sinus mucoceles are benign, slowly enlarging, mucous-secreting, cystic lesions whose expansile growth may lead to compressive neuropathies. We present the case of a 70-year-old woman with a long-standing history of headaches and progressive ocular neuropathy who underwent an endoscopic resection of a large sphenoid sinus mucocele resulting in immediate improvement of her neurological symptoms. The endoscopic endonasal transsphenoidal approach offers a minimally invasive method to manage and treat symptomatic sinus mucoceles.