Postoperative vasospasm of unruptured paraclinoid carotid aneurysms: analysis of 30 cases.

This study was conducted to determine the incidence, severity, and causes of delayed vasospasm after clipping of unruptured paraclinoid aneurysms of the internal carotid artery (ICA). A retrospective analysis was made of 30 patients, who underwent clipping of unruptured paraclinoid aneurysms in our institution between 1991 and 1998. We compared angiograms before and after operation and classified them into two groups: vasospasm group and non-vasospasm group. Eleven variables were assessed as to their relationship to delayed vasospasm. There were 9 patients (30%) in the vasospasm group, of which 3 patients (10%) were clinically symptomatic. For all symptomatic patients, aggressive treatment, including triple-H therapy, was conducted with good outcome. The number of clips used (p<0.04) and temporary occlusion of the ICA (p<0.005) were statistically significant factors associated with the incidence of vasospasm. It is suggested that mechanical stimulation to the vascular wall of the ICA is responsible for causing spasm in addition to intraoperative bleeding around the dural ring.

Immunohistochemical determination of the sympathetic pathway in the orbit via the cranial nerves in humans.

OBJECT: The present study was undertaken to elucidate the extent and precise distribution of the postganglionic sympathetic fibers in the cranial nerves projecting to the orbit and to reconstruct sympathetic routes in the orbit in humans. For this purpose, the authors made an immunohistochemical determination of the sympathetic fibers by using an antibody against norepinephrine-synthetic enzyme, tyrosine hydroxylase (TH). METHODS: Specimens containing the orbit and the cavernous sinus were obtained from formalin-fixed human cadavers. First, it was confirmed that the superior cervical ganglion contained strongly immunostained TH-positive neuronal cell bodies and fibers. After careful dissection of the cranial nerves projecting to the orbit, different segments of each cranial nerve were processed for immunohistochemical analysis for TH. All of the intraorbital cranial nerves contained TH-positive sympathetic fibers, although the amounts were very different in each cranial nerve. At the proximal site of the common tendinous ring, TH-positive fibers were found mainly in the abducent and trochlear nerves. At the distal site of this ring, TH-positive fibers were lost or markedly reduced in number in the abducent and trochlear nerves and were distributed mostly in the ophthalmic and oculomotor nerves. Among the cranial nerves projecting to the orbit, the ophthalmic nerve and its bifurcated nerves--frontal, lacrimal, and nasociliary--contained numerous TH-positive fibers. CONCLUSIONS: The authors conclude that the postganglionic sympathetic fibers are distributed to all cranial nerves projecting to the orbit and that the ophthalmic nerve provides a major sympathetic route in the orbital cavity in humans.

Surgical experience with resection en bloc of intramedullary astrocytomas and ependymomas in the cervical and cervicothoracic region.

We performed 8 operations on 7 patients with benign intramedullary astrocytomas and ependymomas in the cervical and cervicothoracic region. All patients initially underwent gross total tumor resection en bloc. One patient with an astrocytoma showed tumor recurrence postoperatively, and underwent a second operation resulting in subtotal removal. The follow-up after the initial surgery ranged from 2.7 to 19.7 years (mean 8.5 years). Symptomatic improvement was observed in 6 patients after the initial operation. Two patients showed postoperative neurological deterioration, one with an ependymoma and the other after the second operation. No operative complications or deaths, nor postoperative respiratory dysfunction occurred. Benign intramedullary astrocytomas and ependymomas of the cervical and cervicothoracic spinal cord can be treated by radical resection en bloc with a low morbidity and recurrence, as well as acceptable outcomes. We describe here the surgical technique for en bloc tumor removal.

Symmetric dumbbell ganglioneuromas of bilateral C2 and C3 roots with intradural extension associated with von Recklinghausen's disease: case report.

BACKGROUND: Ganglioneuromas are rare benign tumors arising most commonly from the sympathetic nervous system. They occasionally grow in a dumbbell fashion extending into the spinal canal extradurally. However, ganglioneuromas of the cervical spine with intradural extension or multiple locations or in association with von Recklinghausen's disease are rare. CASE DESCRIPTION: A 35-year-old man with von Recklinghausen's disease presented with tetraparesis and respiratory dysfunction. Preoperative neuroimaging revealed an intradural mass extending from the foramen magnum to the C4 vertebral level, as well as bilateral extravertebral extension connecting it with bilateral paraspinal lesions in a dumbbell fashion. Four intradural tumors associated with the bilateral C2 and C3 nerves and located ventrally were removed, leaving the intraforaminal and extradural portion intact. The procedure resulted in postoperative symptomatic improvement. Second, extravertebral tumors of the left neck, which were not related to the cervical sympathetic nerve, were removed. The pathologic diagnosis of the tumors of both the intradural space and cervical neck was ganglioneuroma. CONCLUSION: We present an extremely rare case in an adult with von Recklinghausen's disease who had bilateral, symmetric and multiple dumbbell ganglioneuromas with intradural extension, and also multiple bilateral ganglioneuromas at the neck. The intradural ganglioneuromas were suspected to have originated from the posterior root ganglions of the bilateral C2 and C3 nerves and to have extended ventrally to the spinal cord involving not only sensory but also motor rootlets; the ganglioneuroma of the neck was suspected to have originated from the cervical nerve itself.

Surgical experience of syringomyelia with reference to the findings of magnetic resonance imaging.

We present our surgical experience of 20 patients with syringomyelia, who were divided into two groups based on the findings of magnetic resonance (MR) imaging: a "non-visible cisterna magna" group, in which MR imaging did not reveal cerebrospinal fluid (CSF) in the cisterna magna, and a "visible cisterna magna" group. Patients with non-visible cisterna magna were associated with Chiari malformation (14 patients) or tight cisterna magna (4 patients) and underwent craniocervical decompression. Intradural exploration was performed when CSF movement in the cisterna magna or CSF outflow from the fourth ventricle appeared to be insufficient. It is important to confirm CSF outflow from the foramen of Magendie. Patients with visible cisterna magna were associated with tuberculous meningitis (2 patients) and underwent shunting procedures. Postoperatively, improvement in symptoms and a reduction in syrinx size were demonstrated in all patients except one. Two patients experienced recurrence of symptoms and syrinx dilatation.

Repeat operations in the management of clival chordomas: palliative surgery.

Some chordomas have a very poor prognosis because of their aggressive growth nature, but the efficacy of repeat operations for these cases has not been well documented. This report concerns 3 patients with aggressive chordoma of the clivus, who underwent operations 6 to 12 times over a period of 8 to 17 years because of symptomatic regrowth. Overall mean interval between repeat operations was 18 months with a range from 5 to 57 months and survival times were 9 to19 years after the first surgery. Main symptoms before each operation were diplopia and visual disturbance. Repeat palliative operations by intentional extradural debulking of the tumour to decompress offending neural structures, as well as maximal removal of the tumour, using appropriate skull base approaches, can mitigate progressive symptoms, and may result in better quality and some prolongation of life, although our patients gradually deteriorated neurologically throughout the clinical course.

Degloving transfacial approach with Le Fort I and nasomaxillary osteotomies: alternative transfacial approach.

OBJECTIVE: We present surgical results obtained with the use of an alternative transfacial approach to the central cranial base. METHODS: A degloving transfacial approach, which is a combination of the midface degloving procedure, the Le Fort I osteotomy with a pediculated cartilaginous septum, and a nasomaxillary osteotomy, was used in 13 procedures for 8 patients. The lower clivus and upper cervical spine were approached via a submucosal route, without opening of the oropharyngeal mucosa. The wall of the nasopharynx was closed with the mucosa of the bony septum. Several patients had previously undergone other surgical procedures and received radiotherapy. RESULTS: The follow-up periods ranged from 4 months to 6.4 years. The same procedure was repeated three times for one patient, with intervals of 5.5 and 1.5 months, and twice for three patients, with intervals of 8.2, 6.3, and 1.3 years. A maxillary antrotomy or bifrontal craniotomy with removal of the orbital bar was combined with this technique. No significant or insurmountable technical problems were encountered, even among patients who had undergone previous surgery or radiotherapy. CONCLUSION: Our technique is relatively simple, with good cosmetic results, and affords sufficient access to the central cranial base from the frontal base down to the upper cervical spine, especially for epidural lesions located in the midline between the carotid arteries. It offers much lower risks of damage to vital neurovascular structures, as well as of meningeal or pharyngeal infectious problems, wound dehiscence, and cerebrospinal fluid leakage. This procedure can be repeated without any increase in difficulty.