Minimally invasive approach to management of pituitary adenomas.

Pituitary adenomas are the third most common benign intracranial tumor seen in neurosurgical practice. They represent >or= 15 % of all primary intracranial tumors with 25 % prevalence as reported in autopsy series. Advances in biomedical assays, imaging studies support their diagnosis and tailor their management. The direct endonasal transsphenoidal surgery is the recommended intervention for adenoma resection in more than 95 %. The safety and efficacy of this intervention was enhanced by microsurgery and more recently by the introduction of neuronavigation, assisted endoscopy and intraoperative MRI. Anticipation of clinical, biochemical, radiological and surgical pitfalls by a multidisciplinary team is of paramount importance in improving treatment and preventing potential complications.

Trans-eyebrow mini-orbitozygomatic pterional approach for minimally invasive skull base surgery.

Surgical treatment of skull base pathologies remains one of the most challenging tasks to neurosurgeons. Advances in neuroimaging as well as the evolution of modern techniques and neurosurgical equipment have paved the way for a more precise diagnosis, a better selection of the surgical approach and have prompted the adaptation of minimally invasive concepts to different aspects of modern neurosurgical practice. The trans-eyebrow mini orbitozygomatic pterional approach is a tailored approach that provides multiple avenues to the target, minimizing retraction of the brain and affords better exposure of the pathology. It was performed on 16 patients with frontobasal or suprasellar tumors. The post-operative clinical outcome was excellent with smooth and fast recovery as well as satisfactory cosmetic results. It should be considered as part of the armamentarium to manage skull base lesions when indicated and not to replace other well recognized skull base approaches.

Extra-axial cavernous hemangioma: two case reports.

Two patients with extra-axial cavernous hemangioma who presented with headache and oculovisual disturbances were investigated with computed tomography and magnetic resonance imaging. The lesions masqueraded as basal meningioma, but this diagnosis was not supported by magnetic resonance spectroscopy in one patient. Cerebral angiography with embolization was indicated in one patient, but embolization was not justified in the other. Both patients underwent a pterional craniotomy. The lesions were extradural and highly vascular, necessitating excessive transfusion in one patient in whom gross total resection was achieved, and precluding satisfactory removal in the other. There was no mortality. Transient ophthalmoplegia, the only complication in one patient, was due to surgical manipulation of the cavernous sinus; it resolved progressively over 3 months. Extra-axial skull base cavernous hemangiomas are distinct entities with clinical and radiological characteristics that differ from those of intraparenchymal cavernous malformations. They can mimic meningiomas or pituitary tumors. In some cases, magnetic resonance spectroscopy may narrow the differential diagnoses. Surgical resection remains the treatment of choice, facilitated by preoperative embolization to reduce intraoperative bleeding and by the application of the principles of skull base surgery. Fractionated radiotherapy is an alternative in partial or difficult resections and in high-risk and elderly patients.

ACTH-producing pituitary cancer: experience at the King Faisal Specialist Hospital & Research Centre.

Pituitary gland is an uncommon site of a primary cancer. Of more than 600 cases of pituitary tumors seen at the KFSH&RC between 1975 to 1998 only 3 patients had primary pituitary cancer. We have previously reported a case of pituitary fibrosarcoma arising as a rare complication of external radiotherapy (ERT) for GH-secreting pituitary adenoma (PA) [1]. We report now 2 cases of ACTH-producing primary pituitary carcinoma (ACTH-PPC); their follow-up data provide information on the natural history of this cancer. Patient #1; a 46 year old lady with Cushing's disease (CD) presented with an enlarged right cervical lymph node (LN) 2 years after having undergone a partial hypophysectomy through transsphenoidal surgery (PHYPX/TSS) and ERT for an invasive pituitary tumor. Patient #2; a 26 year old man presented with CD and underwent bilateral adrenalectomy (ADx) and pituitary ERT. Thirty-nine months later he developed Nelson's syndrome and a PHYPX/TSS was performed. Incidentally discovered hepatic metastases in this patient and an excisional biopsy of the LN in patient #1 showed histological features very similar to the pituitary tumor, and they stained strongly positive for ACTH. Perinuclear spherical hyalinized cytoplasmic inclusions were seen in the LN biopsy that corresponded to bundles of type 1 microfilaments (specific for pituitary ACTH-producing cells) seen by electron microscopy. A whole body 18-Fluoro-2-Deoxy-D-Glucose positron emission (FDG-PET) scanning, showed an intense uptake in the neck mass. A trial of octreotide did not change the exceedingly high levels of ACTH in patient #2, further supporting the diagnosis of ACTH-PPC. The clinical course of 102 months prior to his demise showed continued progression of the primary and the metastatic tumor. Patient #1, is alive at 15 months follow-up; hypercortisolemia is controlled using ketoconazole. ACTH-PPC should be entertained in a patient with CD presenting with persistent cervical lymphadenopathy. The clinical course in our patients suggests that the emergence of PC may involve a proliferative continuum from a pre-existing PA to an invasive tumor, culminating in a carcinoma. Adjunctive events such as ERT/ADx may predispose to the evolution of PC in genetically susceptible individuals. Because ERT is an effective treatment for PA its use will continue; it is important to be aware of the possible complication of primary pituitary carcinoma.

Osteoplastic laminotomy as a minimally invasive spinal procedure.

A minimally invasive surgical technique is demonstrated to perform osteoplastic laminotomy. It consists of protection of the dural sac and the nerve roots with a rubber or silicone tube, cutting of the laminae with an oscillating saw and bilateral refixation of the laminae. This simple and safe technique, which has been used by the authors for six years, provides good stability of the spine postoperatively and helps to avoid post-laminectomy membrane formation.

Non-neoplastic cystic lesions of the sellar region presentation, diagnosis and management of eight cases and review of the literature.

The differential diagnosis of a sellar lesion includes pituitary adenoma, cranio-pharyngioma, tumour cyst, benign cyst, and other less common lesions such as aneurysm, squamous cell carcinoma and metastases. Pure cystic lesions within the sella turcica are not uncommon and may appear clinically and radiologically as pituitary adenoma. Intrasellar cysts are broadly classified as neoplastic or non-neoplastic; the latter may be primary lesions of the pituitary fossa or they may arise from the parasellar region and invade into the sella. The lesions occupy space and may cause disturbance of pituitary function; if they extend into the suprasellar region they can affect visual fields and acuity. Non-neoplastic cystic lesions usually appear well defined radiologically and have distinct pathological features. Modern imaging modalities, such as computed axial tomography and magnetic resonance imaging, are important complementary tools of investigation for reaching a differential diagnosis, and for surgical planning. Most non-neoplastic sellar cysts can be approached through the trans-sphenoidal route, but large lesions with suprasellar extension may require transcranial surgery. We report the presentation and management of eight cases (four males, four females, all adult) of non-neoplastic cyst involving the sella turcica and the parasellar region. Investigations included computed tomography scan of the head for all and magnetic resonance imaging for six (75%) patients. Work-up included endocrinological and opthalmological evaluations. All presented with headache; six (75%) had visual acuity change, two (25%) had evidence of visual field defects, four (50%) had optic atrophy on fundoscopy, three (37.5%) had endocrine symptoms and hormone reduction was found in four (50%).

Craniocervical junction tuberculosis: a rare but dangerous disease.

BACKGROUND: Mycobacterium tuberculosis of the cervical spine is a rare but dangerous manifestation of extra-pulmonary tuberculosis. The clinical picture ranges from early, nonspecific, insidious symptoms to severe neurological complications and death, attributed to craniocervical junction instability and cervicomedullary compression. The different lines of management include antituberculous medication with traction and external fixation or adjunctive surgery (debridement and stabilization) in patients with severe or persistent neurological complications and/or vertebral instability. METHODS: We describe two patients with advanced craniocervical junction tuberculosis. The early clinical picture was nonspecific in Case 1 and obscured by psychiatric illness in Case 2. The detailed clinical and radiological findings, and the management, will be described. Involvement of the occipital condyles and foramen magnum, which has not been reported previously, will be demonstrated. RESULTS: Both cases underwent transoral biopsy, aspiration, and debridement of retropharyngeal abscess (granuloma). Histological and tissue culture studies proved the abscesses were tuberculous and anti-tuberculous medications were started. Case 1 showed complete resolution of the clinical and radiological findings. Case 2 developed cardiorespiratory arrest while in a halo jacket. He was resuscitated but remained quadriplegic and semiconscious; he developed nosocomial gram negative pneumonia. He was referred back to his local hospital where he died 1 year later. CONCLUSIONS: Tuberculosis is an infrequent but notable cause of cervicomedullary compression. It should be suspected in patients with infective spondylitis who are immunocompromised or reside in an area highly endemic for tuberculosis. Management strategies include antituberculosis medication, transoral biopsy and drainage of the abscess, traction and external fixation, posterior decompression, and internal fixation, according to the clinical and radiological findings.

Aneurysmal bone cyst involving the skull base: report of three cases.

Aneurysmal bone cyst is a bening, non-neoplastic lesion that present most frequently under the age of 20 years. The metaphysis of long bones is the usual site of origin. The involvement of the skull is rare. In the 2.5 to 6% of such cases reported in the literature, the skull vault is more often the site than the skull base. Three cases of aneurysmal bone cyst involving the skull base have been managed at King Faisal Specialist Hospital and Research Center. Two females and one male, all 10 years of age and younger, presented with a painless, progressive swelling. The preoperative radiological studies showed characteristic findings and were highly suggestive of the diagnosis. Angiography also gave characteristic findings. Preoperative endovascular embolization of the arterial feeders to the tumor was performed in two patients who had a significant decrease in intraoperative bleeding from the tumor. All cases underwent surgical excision with a good outcome.

Craniopharyngioma in children.

PURPOSE: The treatment regimens at presentation and recurrence, the related morbidity, and survival rates were studied for children with craniopharyngioma who were treated at King Faisal Specialist Hospital & Research Center (KFSH&RC). METHODS & MATERIALS: From 1975 to 1996, a total of 56 children younger than 18-years-old at diagnosis underwent treatment with surgery and/or radiotherapy for craniopharyngiomas at KFSH&RC. There was evidence that these patients had advanced disease at diagnosis; 36% of 51 patients whose visual status pretreatment was known were either blind or had major bilateral visual defects prior to treatment, and 36% of the 56 patients had diabetes insipidus. This report concentrates on 44 patients who had first definitive resection at KFSH&RC. Treatment policy was total resection if possible (17 patients), if not, subtotal resection (17 patients) or lesser procedures (10 patients). Five patients received postoperative irradiation after first definitive resection. RESULTS: Ten-year-survival, and progression-free and event-free survival rates were 65%, 39%, and 29%, respectively. There were 9 postoperative deaths; 7 following the first procedure and 2 following resection for relapse, and 3 early deaths at home prior to relapse, following the first resection. None of the 22 patients who underwent less than total resection without postoperative radiation treatment were progression-free at 5 years, whereas the 5 patients who were irradiated remain progression-free. CONCLUSION: A more selective approach to total resection, and the routine use of postoperative irradiation following lesser surgical procedures requires evaluation.

Human ARHGDIG, a GDP-dissociation inhibitor for Rho proteins: genomic structure, sequence, expression analysis, and mapping to chromosome 16p13.3.

GDP-dissociation inhibitors (GDIs) play a primary role in modulating the activity of GTPases. We recently reported the identification of a new GDI for the Rho-related GTPases named RhoGDIgamma. This gene is now designated ARHGDIG by HUGO. Here, in a detailed analysis of tissue expression of ARHGDIG, we observe high levels in the entire brain, with regional variations. The mRNA is also present at high levels in kidney and pancreas and at moderate levels in spinal cord, stomach, and pituitary gland. In other tissues examined, the mRNA levels are very low (lung, trachea, small intestine, colon, placenta) or undetectable. RT-PCR analysis of total RNA isolated from exocrine pancreas and islets shows that the gene is expressed in both tissues. We also report the genomic structure of ARHGDIG. The gene spans over 4 kb and is organized into six exons and five introns. The upstream region lacks a canonical TATA box and contains several putative binding sites for ubiquitous and tissue-specific factors active in central nervous system development. Using FISH, we have mapped the gene to chromosome band 16p13.3. This band is rich in deletion mutants of genes involved in several human diseases, notably polycystic kidney disease, alpha-thalassemia, tuberous sclerosis, mental retardation, and cancer. The promoter structure and the chromosomal location of RhoGDIgamma suggest its importance and underscore the need for further investigation into its biology.

Sphenoid sinus brown tumor of secondary hyperparathyroidism: case report.

OBJECTIVE AND IMPORTANCE: Brown tumor is a misnomer for a reparative cellular process caused by primary or, less commonly, secondary or tertiary hyperparathyroidism. Atypical involvement of the base of the cranium in the area of the sphenoid sinus and the orbit is exceedingly rare and may produce a neurological deficit as a primary clinical presentation. Those neurosurgeons dealing with cranial base and pituitary lesions should be aware of this disease entity, and it should be listed in the differential diagnosis. CLINICAL PRESENTATION: A 21-year-old woman with end-stage renal failure on chronic dialysis was referred to the Department of Neurosciences at King Faisal Specialist Hospital and Research Centre with a 4-month history of progressive impairment of vision, associated with headache and nausea. Computed tomography and magnetic resonance imaging demonstrated an expansive mass lesion in the sphenoid sinus with erosion of the sellar floor and posterior medial wall of the orbit causing compression of the optic nerves. The biochemical laboratory studies showed elevation of parathyroid hormone and confirmed the diagnosis of hyperparathyroidism. INTERVENTION: The transnasal-transsphenoidal approach was used for extensive microsurgical removal of the lesion. The postoperative course was uneventful, and the improvement in vision was dramatic. CONCLUSION: Brown tumor, although rare, should be listed in the differential diagnosis of expansive mass lesions in the area of the sphenoid sinus and cranial base. The management is multidisciplinary, and therapeutic options should target the underlying cause.

Neurosurgical aspects of sphenoid sinus mucocele.

The aetiological spectrum of sphenoid sinus mucocele includes congenital anomaly, trauma, infection, allergy and surgery of the sphenoid sinus. Enlargement of the mucocele, even with a short history, can result in progressive expansion of the sinus and extension of the lesion into the pituitary fossa, the suprasellar region, nasopharynx, orbits, clivus or ethmoid air cells. It is a benign cystic lesion with an excellent prognosis when treated appropriately. Generally, these lesions are managed by an ear, nose and throat surgeon, but when there is extension into the sellar and parasellar (especially suprasellar) regions they are managed by the neurological surgeon. Sphenoid sinus mucocele should be considered in the differential diagnosis when there is suspicion of a cystic lesion in these regions. Three cases of large sphenoid sinus mucocele are presented, with discussion on their neurosurgical management and a review of the literature.

Aneurysmal disease in children. Review of 20 cases with intracranial arterial localisations.

SUMMARY: Twenty children (13 males, 7 females), referred to our group with non traumatic intracranial aneurysms between 1978 and January 1997, were included in this study. Their angiograms were reviewed to assess number, location, type of aneurysms and evolution before and after treatment. Their ages ranged from 1 month to 15 years. Seven patients (35%) presented with subarachnoid haemorrhage (SAH). Eleven patients (55%) presented with focal neurological deficits or seizures: epileptic seizures occurred in five patients, neurologic deficits or focal symptoms due to mass effect occurred in six. Total number of diagnosed intracranial aneurysms was 24. The most common sites involved were internal carotid (37%) and vertebrobasilar (32%) systems. The aetiology of the aneurysms was infective in four patients and unknown in the remaining 16 patients (80%). Endovascular treatment was successful in seven patients (37%). Three patients (15%) were surgically treated. Seven patients (35%) were conservatively treated. Two patients (10%) had spontaneous thrombosis of the aneurysm. SAH was more frequent in males, and never occurred in children under five years old. Frequent presentations such as focal symptoms or mass effect and less prevalence of aneurysm rupture are probably due to the high prevalence of large or giant aneurysms (25%) in our series. In conclusion, radiological findings and the natural history of symptomatic arterial aneurysms in children are clearly different from those in adults. Probably pathogenetic factors and aetiology are also different. Shear stresses, haemodynamic and hormonal factors do not appear to be dominant to reveal such defects, though their correction favours repair. Since repair is frequent, conservative treatment has a major role in their aneurysm management.

Atypical course of carotid cavernous sinus fistula in a six-year-old child.

A case of post-traumatic carotid cavernous sinus fistula complicated by coma-producing intraventricular tamponade in a 6-year-old boy is reported. Urgent surgical treatment included external ventricular draining, trapping and muscle embolization by the Jaeger-Hamby procedure. Follow-up cerebral angiography showed complete obliteration of the fistula. The child made an excellent recovery and now leads a normal life.

Suprasellar meningioma and blindness: a unique experience in Saudi Arabia.

BACKGROUND: The natural history of intracranial meningioma is no different in the Arabian peninsula than in other countries. The extent of the total loss of vision in one or both eyes, however, is unique to this area. METHODS: A retrospective study was conducted at King Faisal Specialist Hospital and Research Centre, a tertiary care institution in Saudi Arabia, on all cases of intracranial meningioma seen over a period of 9 years. The following data were collated: clinical presentation, site and size of tumor, radiologic features, surgical methods, and preoperative and postoperative visual status. RESULTS: Seventy of 232 cases (30.1%) of intracranial meningioma presented in the suprasellar area; the majority of these were more than 5 cm in diameter. Because of the large size it was not always possible to identify the exact point of origin or to achieve complete tumor removal. Deteriorating vision was the cardinal presenting feature and the incidence of blindness in one or both eyes at presentation was high (42.2%); 12.8% were totally blind on admission. None of these patients showed improvement after surgery (complete or subtotal removal of tumor). CONCLUSION: Lack of understanding of the symptoms and cultural influences are direct contributing factors to this complication of a benign intracranial lesion. This represents a serious public health concern in the Arabian peninsula.

The spectrum of intracranial aneurysms in pediatrics.

Intracranial aneurysms are rare in children, accounting for merely 0.5-4.6% of all aneurysms. Several characteristics distinguish them from aneurysms in adults: male predominance; higher incidence of unusual location, such as peripheral or posterior circulation; and a greater number of large and giant aneurysms. These unique features can be attributed to the higher incidence of traumatic, infectious, developmental, and congenital lesions. Subarachnoid hemorrhage is not the exclusive mode of presentation; neuro-compressive signs and symptoms are also frequently seen. The treatment of intracranial aneurysms in pediatrics is dictated by their unusual pathology and liability to rehemorrhage. Although direct clipping has been the standard surgical technique, certain obsolete or innovative procedures should also be considered, such as entrapment, proximal occlusion, and endovascular embolisation, or even, in some cases, the non-invasive treatment of "watch and wait" for a spontaneous thrombosis. Six representative cases from King Faisal Specialist Hospital and Research Centre are reviewed. They reflect the diversity of the problem and the multi-disciplinary approach to the treatment.

Medulloblastoma in adults.

Seventeen adult patients (16 years of age and over) with medulloblastoma were managed at King Faisal Specialist Hospital and Research Centre between 1981 and 1992. Nine patients were males and eight were females. The average age at diagnosis was 26.7 years; the females were younger than the males. The average duration of history before diagnosis was 14.5 weeks, the females presenting earlier than the males. The tumors were located in the midline (9) and the hemispheres (8). Nine patients had the desmoplastic variant and eight had standard primitive neuroectodermal tumor. Hydrocephalus developed in 14 of the patients only seven of whom required a shunting procedure. All patients had either subtotal or gross total removal of the tumor. Sixteen patients had postoperative radiation therapy; one patient refused radiation therapy. Two patients had chemotherapy following recurrence of the tumor. The clinical presentation, radiological studies, histological variants, treatment and outcome are discussed in this report.

Brain tumors in the first 2 years of life in Saudi Arabia.

Thirty-four patients with brain tumors were diagnosed and treated during the first 2 years of life, representing 8% of the 273 children treated for primary brain tumors from 1981 to 1990 inclusive. Large head circumference, vomiting, and altered level of consciousness were the chief findings at the time of presentation. Overall, the tumors were located mainly supratentorially; in patients in the 1st year of life they were equally distributed above and below the tentorium, while two-thirds of the patients presenting in the 2nd year of life had supratentorial tumors. The most common histological types were astrocytomas and medulloblastomas. Treatment methods were ventricular peritoneal shunt, craniotomy with total or partial removal of the tumor, adjuvant radiotherapy, and in a few cases chemotherapy. The 2-month mortality rate was 5.9%. The follow-up period ranged from 3 to 50 months.