Collagen matrix as an inlay in endoscopic skull base reconstruction.

BACKGROUND: Multi-layer reconstruction has become standard in endoscopic skull base surgery. The inlay component used can vary among autografts, allografts, xenografts and synthetics, primarily based on surgeon preference. The short- and long-term outcomes of collagen matrix in skull base reconstruction are described. METHODS: A case series of patients who underwent endoscopic skull base reconstruction with collagen matrix inlay were assessed. Immediate peri-operative outcomes (cerebrospinal fluid leak, meningitis, ventriculitis, intracranial bleeding, epistaxis, seizures) and delayed complications (delayed healing, meningoencephalocele, prolapse of reconstruction, delayed cerebrospinal fluid leak, ascending meningitis) were examined. RESULTS: Of 120 patients (51.0 ± 17.5 years, 41.7 per cent female), peri-operative complications totalled 12.7 per cent (cerebrospinal fluid leak, 3.3 per cent; meningitis, 3.3 per cent; other intracranial infections, 2.5 per cent; intracranial bleeding, 1.7 per cent; epistaxis, 1.7 per cent; and seizures, 0 per cent). Delayed complications did not occur in any patients. CONCLUSION: Collagen matrix is an effective inlay material. It provides robust long-term separation between sinus and cranial cavities, and avoids donor site morbidity, but carries additional cost.

Migration of lumbar disc herniation: an unusual case.

We illustrate a patient with a migrating lumbar disc fragment that caused a change in radicular symptoms from the L3 nerve root on one side to the L5 nerve root on the contralateral side, documented by magnetic resonance imaging (MRI). Our patient presented with 3 months of L3 pain on the right side with sensory and motor changes. Over a 24-hour time period, the right leg pain disappeared and he developed left leg pain attributable to left L5 nerve root compression. Investigation with MRI revealed an epidural mass, which was hypointense on Tl-weighted and T2-weighted images that had migrated, initially compressing the right L3 nerve root, to now compress the left L5 nerve root. The patient did not wish to pursue surgery. Disc fragment migration patterns are discussed. We conclude that extruded disc fragments may migrate distant from their initial origin.

CT guided aspiration of a cervical spinal epidural abscess.

The management of spinal epidural abscess has changed over the last few years. Originally treatment was thought to be urgent surgical evacuation. In the more recent literature less invasive techniques have been suggested. We present a case, where a cervical epidural abscess at the C2 level was treated with CT guided aspiration and antibiotic therapy. This has not been previously reported.

Paragangliomas of the sellar region: report of two cases.

Two cases of paraganglioma arising from the parasellar region are presented. Both occurred in middle-aged women who sought treatment of headaches but who had no endocrinological dysfunction; one case was associated with ophthalmoplegia from cavernous sinus involvement. Diagnosis in both cases was confirmed by typical histological appearance and cytochemical demonstration of immunoreactive chromogranin in tumor cells. The pathological features and possible pathogenesis of parasellar paragangliomas are discussed.

Anchoring of deep brain stimulation electrodes using a microplate. Technical note.

The authors report a new technique to anchor deep brain stimulation electrodes using a titanium microplate. This technique has been safely used to secure 20 quadripolar deep brain stimulation electrodes implanted for movement disorders (18 electrodes) and pain (two electrodes). Twelve electrodes were implanted in the thalamus, four in the subthalamic nucleus, and four in the pallidum. No electrode migration or rupture occurred, and all electrodes have been shown to work properly after internalization of the system.

Spinal epidural leiomyoma occurring in an HIV-infected man. Case report.

A case of spinal epidural leiomyoma is reported in a 52-year-old man infected with the human immunodeficiency virus (HIV). The tumor arose in the epidural region at the T-3 vertebral level, and the patient presented with radicular pain in the right T-3 dermatome. While soft-tissue tumors such as Kaposi's sarcoma and lymphomas have been well documented in association with HIV infection, this is the first reported case of primary spinal leiomyoma. Isolated cases of leiomyomas and leiomyosarcomas in unusual locations have been reported, notably in pediatric HIV-positive patients, perhaps indicating a causal relationship. This case may represent further evidence of such an association.

Intradural neurotropic spread of malignant mesothelioma. Case report and review of the literature.

This 54-year-old man with a history of right-sided malignant mesothelioma presented with signs of a partial spinal cord syndrome. The tumor had invaded the lower trunk of the brachial plexus and spread along the T-1 nerve root beneath the arachnoid onto the spinal cord itself. Mesothelioma, despite its known predilection for local spread, is rarely encountered within the spinal canal. Neurotropism is commonly encountered in facial malignancies; however, it has never been reported to affect the brachial plexus and spinal cord.

A multidisciplinary team approach to skull base chordomas.

OBJECT: A multidisciplinary team devised a protocol for long-term care of patients with skull base chordomas. In this study they describe their approach. METHODS: Forty-two patients presented between 1986 and 1998 and were treated by maximum surgical cytoreduction and photon radiation therapy. Tumor volume-doubling time determined on the basis of magnetic resonance imaging, immunostaining, and cell proliferation (Ki67 labeling index [LI]) studies indicated growth rates of individual chordomas. The best outlook was associated with the greatest extent of tumor removal achieved during the first operation. There were no deaths associated with patients who underwent first-time surgery, but there was a 7.1% mortality rate associated with those who underwent subsequent operations. Cerebrospinal fluid leaks, additional cranial nerve palsies, and pharyngeal wound problems were the most difficult management problems encountered after second and subsequent surgeries. The time interval between operations was usually between 2 years and 3 years after the first surgery; very few patients required a second surgery, with a quiescent period in excess of 5 years. Life-table 5- and 10-year survival rates were 77% and 69%, respectively. CONCLUSIONS: The authors believe that this series of skull base chordomas provides new insights into the management of these lesions, particularly with regard to techniques that increase survival times and studies that aid in formulating prognoses.

A multidisciplinary team approach to skull base chondrosarcomas.

OBJECT: The authors review their experience with treating skull base chondrosarcomas, which are much rarer than skull base chordomas and differ from them in prognosis and treatment. METHODS: Seventeen patients (12 male and five female patients) with histologically verified chondrosarcomas were followed up prospectively over a 12-year period. The mean age at presentation was 35.9 years. Most patients presented with cranial nerve palsies. Seven had undergone surgery prior to referral to the authors' unit. All underwent maximum surgical cytoreduction by the most direct surgical approach; only the two patients harboring the mesenchymal variant underwent radiotherapy. CONCLUSIONS: One patient died of a pulmonary embolus; the patients harboring mesenchymal chondrosarcomas died at 20 and 36 months, respectively, after treatment. Of the remaining patients, 93% were alive 5 years postsurgery and had a projected 10-year survival rate of 84% (mean survival time 9.3 years). These data emphasize the very slow progression of this tumor compared with skull base chordoma.

Paraganglioma of the cauda equina with associated syringomyelia: case report.

We present an association not previously described in which the rare entity of paraganglioma of the cauda equina was found in association with syringomyelia of the cervico-thoracic cord. The patient, a 50-year-old woman presented with a long history of lower back pain with recent onset of sciatic pain and altered sensation in the right leg. Surgical resection of the tumor with intraoperative syringostomy of the syrinx has led to eradication of all symptoms and at 5 months shows no evidence of residual pathology.

Demonstration of membranous aqueduct occlusion by fast multiphase magnetic resonance imaging.

Membranous aqueduct occlusion is one of the few causes of obstructive hydrocephalus that is amenable to direct surgical treatment. Conventional diagnostic methods may not delineate this entity. The advent of dynamic fast multiphase magnetic resonance imaging has improved the definition of the aqueductal membrane by enabling visualization of the obstructed cerebrospinal fluid flow within the ventricular system. We report a case of a 10-year-old boy in whom the diagnosis of membranous aqueduct occlusion was only achieved utilizing this new technique.

Intraoperative wound infiltration with bupivacaine in patients undergoing lumbar spine surgery.

We conducted a randomized double-blind trial to evaluate the effect of intraoperative wound infiltration with bupivacaine 0.25% (1 ml/kg) compared to placebo (NaCl 0.9% 1 ml/kg) in patients undergoing lumbar spine surgery. Fifty-two patients were entered in the trial and 50 completed it. Two methods of wound infiltration were assessed: (a) infiltration after partial wound closure and (b) infiltration prior to wound closure. Postoperatively patients received morphine sulfate on demand. Visual analog pain scores were recorded every 2 h for 12 h after the operation. Analgesia requirements were recorded over the duration of the study for each patient. The patients who received bupivacaine infiltration prior to wound closure had significantly reduced pain scores in the recovery room and used significantly less morphine in the first 2 h following the procedure. They also had reduced pain scores and reduced morphine demand in the first 10 h but this did not reach statistical significance. No difference was noted between the placebo group and those receiving infiltration after partial wound closure. It is concluded that infiltration of bupivacaine is a simple and safe aid in obtaining analgesia in patients undergoing lumbar spine surgery provided that it is infiltrated prior to wound closure.

Endoscopic treatment of spinal epidural hematoma.

We report the use of a spinal endoscope via a limited cervical laminotomy to evacuate a spinal epidural hematoma. The patient was a 75-year-old male with a 32-year history of ankylosing spondylitis. Following a low speed motor vehicle accident he developed a cervicothoracic epidural hematoma without an associated fracture. Despite a rapidly improving neurological state, his rapidly deteriorating cardiorespiratory state required systemic anticoagulation necessitating decompression of the hematoma. The hematoma was successfully removed via a limited C6 and C7 laminotomy using the endoscope and a malleable disposable aspirator. We conclude that epidural hematomas can be readily evacuated via endoscopic techniques without extensive laminectomy. This technique may be used for approaching intraspinal pathology in high risk patients where extensive exposure may be contraindicated.

Recurrent nocardial brain abscesses treated by repeated stereotactic aspirations.

A case of a 61-year-old diabetic patient who had a new onset simple partial seizure is presented. Past medical history was remarkable for pulmonary sarcoidosis for which the patient was on chronic steroid therapy. Computed tomography scan demonstrated a postcentral abscess which was aspirated under stereotactic guidance. Nocardia asteroides was identified. The patient was placed on intravenous trimethoprim and sulfamethoxazole. He required two further stereotactic aspirations of recrudescences until symptoms resolved. The use of repeated stereotactic aspiration in place of an open surgical procedure is advocated for the treatment of nocardial abscesses.

An anterior expandable titanium cage in Mycobacterium avium vertebral osteomyelitis.

Mycobacterial infection is most commonly caused by Mycobacterium tuberculosis. M. avium and M. intracellulare are two other organisms within the Mycobacteria group often classified together as the mycobacterium avium-intracellulare complex (MAC). MAC is of low virulence and usually causes disease in immunocompromised patients such as those with the human immunodeficiency virus. Isolated vertebral osteomyelitis secondary to MAC infection is rare with only 18 previous reports, only one of which required surgical intervention. There is increasing evidence that vertebral body osteomyelitis with other pathogens can be treated with decompression, debridement and reconstruction with titanium vertebral body cages in the setting of active infection. We present a 70-year-old Caucasian male with a pathological fracture of T6 vertebral body and a kyphosis of 60° and MRI findings consistent with granulomatous osteomyelitis. Vertebrectomies of T5 and T6 were performed and an expandable titanium cage was inserted with supplementary lateral fixation using plate and screws. This is the first report of a single-stage decompression and fusion with a titanium vertebral body cage for active MAC vertebral osteomyelitis.

A rosette-forming glioneuronal tumour of the pineal gland.

A rosette-forming glioneuronal tumour (RGNT) is a rare tumour with new information emerging. We review the literature and describe the second patient with a RGNT arising from the pineal gland. This is also the fifth report of a RGNT arising from outside the fourth ventricle. The prognosis of RGNT remains guarded, as long-term follow-up is not yet available for most patients reported. With only one of 35 patients having a documented recurrence at 10 years, the prognosis seems favourable with appropriate, but not necessarily total, surgical resection.

Spinal epidural lipomatosis due to a bronchial ACTH-secreting carcinoid tumour.

Spinal epidural lipomatosis (SEL) is a rare condition characterized by abnormal deposits of fat in the epidural space. In a severe form this may cause compression of neural elements. This is the second report of SEL secondary to a carcinoid tumour. Our patient was a 34-year-old Caucasian male farm worker presenting with acute spinal cord compression. He had gained 11kg, and had developed Type II diabetes mellitus in the preceding 12months. On examination he displayed characteristic features of Cushing's syndrome. MRI demonstrated posterior epidural lipomatosis, with cord compression from T3 to T8. Urgent spinal cord decompression was performed. Further investigation confirmed a biochemical Cushing's syndrome secondary to an ACTH-producing pulmonary carcinoid tumour.

Vascular neurofibromatosis affecting the internal carotid artery: a case report.

A patient with von Recklinghausen's disease presented with a right sixth nerve palsy. Investigations demonstrated unilateral dolichoectasia of the intracranial carotid artery and sphenoid wing dysplasia. This case demonstrates an association not previously documented, that of unilateral fusiform dilatation of the carotid artery with sphenoid wing dysplasia in the presence of classical neurofibromatosis.

Skull base chordomas: correlation of tumour doubling time with age, mitosis and Ki67 proliferation index.

The aim of the study was to assess the relationship between the rate of clinical tumour growth and various histological features, including Ki67 labelling index, in skull base chordoma. Cases of skull base chordoma from 19 patients (six female, 13 male; age range 8-63 years) were reviewed and the diagnosis confirmed based on histological and immunohistochemical features. In each biopsy cellularity, pleomorphism, mitotic activity, apoptotic bodies, necrosis and inflammatory cell infiltrate were graded and Ki67 labelling index (LI) calculated as a measure of proliferation. Tumour doubling time was assessed by quantitative analysis of tumour volumes in post-operative magnetic resonance images and correlated with age, sex, histological parameters and Ki67 LI. It was shown that increasing patient age, the presence of mitotic figures or a Ki67 LI in excess of 6% were associated with faster growing tumours.