Hemifacial spasm due to aneurysmal compression of the facial nerve.

Hemifacial spasm developed in a woman as the only symptom of an aneurysm of the posterior inferior cerebellar artery. Using microdissecting techniques, the aneurysm was clipped and moved from its distorting position at the brain stem exit zone of the seventh nerve. After surgery, she experienced immediate relief of her facial spasm of six years' duration. This case supports the finding that hemifacial spasm may be caused by vascular lesions of the seventh nerve at the brain stem junction. Recent surgical experience indicates that the majority of the hemifacial spasm cases may be due to normal but ectatic blood vessels that cross-compress the most proximal portion of the seventh nerve. Relief may be affected without facial paralysis by a retromastoid microvascular decompressive procedure.

Extra- to intracranial arterial anastomoses in therapeutic embolization: recognition and role.

Anastomoses from extra- to intracranial vessels have been shown in normal patients and, more commonly, in patients with arteriosclerotic occlusive disease, arteriovenous malformation, and postligation of the carotid artery. These channels may be of clinical importance during therapeutic embolization and probably account for two cases of complication, posterior fossa strokes that occurred after blockage of occipital arteries. By identifying these channels and then monitoring the ever-decreasing vessel acceptance of contrast agent and emboli, patient safety may be enhanced.

Callosomarginal infarction secondary to transfalcial herniation.

To evaluate the prevalence of anterior cerebral artery infarcts in the context of transfalcial herniation, 1100 cerebral CT scans were reviewed. Three patients had acute intracranial hemorrhages resulting in transfalcial herniation and subsequent focal ipsilateral paracentral lobule or superior frontal gyrus infarcts. The infarcts are presumed to have resulted from compression and compromise of the terminal portions of the callosomarginal artery against the falx. Callosomarginal infarcts are reflective of severe, acute hemispheric insult. As such, they seem to portend a declining clinical condition, and thus may provide another CT indication of a poor clinical outcome.

Computed tomography and myelography of the postoperative lumbar spine.

Postoperative myelographic changes in the thecal sac, epidural tissues, and bony canal, as well as nerve roots, may be difficult to interpret. A series of 32 postoperative patients, all of whom had a metrizamide myelogram and subsequent lumbar computed tomogram, was reviewed to examine the ability of computed tomography to recognize abnormalities when the myelogram is equivocal or uninterpretable. Criteria to distinguish recurrent herniated disk from postoperative changes are presented, including the demonstration of mass densities similar to and in continuity with the intervertebral disk. In 12 reoperated cases, five recurrent herniated disks and two new herniated disks were diagnosed and confirmed. In 20 nonreoperated cases, no recurrent herniated disks were identified, although two new herniated disks were found at levels not believed clinically significant. Computed tomography after metrizamide myelography appears to be a reliable technique for distinguishing abnormalities in the postoperative spine.

Intrasellar mucocele simulating pituitary adenoma: case report.

Mucoceles occupying the sella turcica with suprasellar extension are quite rare. A case of intrasellar mucocele is reported. The preoperative clinical and computed tomographic appearance could not be differentiated from that of pituitary adenoma.

Intraoperative angiography and temporary balloon occlusion of the basilar artery as an adjunct to surgical clipping: technical note.

The direct surgical treatment of intracranial aneurysms is not always possible, especially in posterior circulation aneurysms. This is usually because of their complex anatomy and location next to the skull base and brain stem, where proximal vascular control is usually not attainable. Four patients at our institution underwent intraoperative transfemoral catheterization of the basilar artery with a nondetectable endovascular balloon for proximal control of the basilar artery. The flow control in the basilar artery was excellent and facilitated the surgery. Before surgery, each patient underwent the placement of a 10-cm 8-French femoral introducer sheath and were taken to the operating room where they were placed in a supine position and a subtemporal or pterional craniotomy was performed. After the initial exposure and before aneurysm manipulation, a nondetachable silicone balloon catheter was passed through an introducer catheter and was placed into the rostral basilar artery, using flow direction, microguidewires, and angiographic "road-mapping" techniques. In two patients, temporary basilar occlusion was used to collapse the aneurysm and to facilitate clip placement. In the third patient, intraoperative aneurysm rupture occurred and was controlled by temporary basilar artery occlusion. Using intraoperative angiography, complete aneurysm obliteration and vessel patency was confirmed in all four patients. All patients made a complete recovery except for initial postoperative third nerve palsies in three patients. This technique achieves intraoperative control of the basilar artery proximal to an aneurysm by the use of a nondetachable occlusive balloon in the basilar artery. An added benefit is the ease with which intraoperative angiography can be obtained in this context.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute tissue tear hemorrhages of the brain: computed tomography and clinicopathological correlations.

Tissue tear hemorrhages (TTHs) are often seen on high-resolution computed tomographic scans after closed head injury. Generally, TTHs have been thought to be visible manifestations of more severe forms of diffuse axonal injury and thus portend a poor prognosis. Computed tomographic scans from 600 patients with head injuries were reviewed; 48 (8%) were found to have TTHs. The clinical spectrum of TTHs was characterized. No direct relationship could be established between either the presence or the number of TTHs and the severity and/or outcome from the head injury in this group, except that patients with TTHs in both the brain stem and the corpus callosum uniformly had a poor outcome. Magnetic resonance imaging provided more sensitive information than computed tomography in evaluating TTHs.

Fibrosis surrounding a silicone implant simulating recurrent orbital meningioma. Case report.

A patient with the preoperative diagnosis of recurrent orbital apical meningioma was found to have a fibrotic capsule surrounding a silicone plate implanted 3 years previously to reconstruct the orbital roof. Caution is urged in using alloplastic orbital implants for reconstructive purposes in patients undergoing orbital surgery, because associated fibrous capsule formation may mimic tumor recurrence.

Radiographic temporal bone template as an aid in vestibular nerve section.

We have used a temporal bone middle fossa X-ray template for vestibular nerve localization during surgery. This has proved helpful and it is recommended on all patients undergoing middle fossa approach for vestibular nerve section.

Opacification of the lumbar epidural venous plexus during myelography.

Opacification of the regional epidural venous plexus is an untoward circumstance of myelography. The following case reports demonstrate the epidural veins and the transient pulmonary symptoms that resulted.

Degenerative disease of the lumbar spine. Role of CT-myelography in the MR era.

One hundred patients with degenerative disease of the lumbar spine on whom both magnetic resonance (MR) and computed tomography (CT)-myelography were performed were reviewed. In one-third of the cases, the CT-myelogram provided additional useful information. This included definition of the extent of large disc herniations, demonstration of focal neural compression by small herniations, and clarifying abnormalities of the facets, including synovial cysts. These results should help to refine the indications for CT-myelography, which continues to be requested extensively.

Absent cord sign in acute spinal trauma.

Review of magnetic resonance imaging (MRI) findings in 100 patients suffering acute spinal trauma from 1985 to 1987 revealed four patients who had suffered thoracic spine fractures and acute subarachnoid hematomas. The spinal cord was not demonstrated on the T1-weighted sagittal MRI due to the similarities in signal intensity between the spinal cord and acute hemorrhage. Nonvisualization of the thoracic cord should not be presumed to be artifactual until subarachnoid hematoma is excluded.

Coaxial needle technique for lumbar puncture in the morbidly obese patient.

The authors describe a method of enhancing the ease of lumbar puncture in the morbidly obese patient. In their experience, the coaxial needle technique shortens fluoroscopic and total procedure times when obtaining cerebrospinal fluid for laboratory analysis or when performing myelography.

Diagnosis of sacral perineural cysts by computed tomography.

Three cases of sacral perineural cysts associated with chronic low-back pain are described with their myelography, computed tomography, and plain film findings. Significant findings include multiple cystic dilatations of lumbosacral nerve root sheaths, enlargement of the sacral foramina by masses isodense with cerebrospinal fluid, and asymmetric epidural fat distribution. Recognition of these findings on unenhanced computed tomography scans should preclude further evaluation by myelography and intrathecal metrizamide (Amipaque) computed tomography. These cysts are usually not the primary cause of back and leg pain.

Case report: computed tomography findings in spinal arachnoiditis ossificans.

Spinal arachnoiditis ossificans is rarely diagnosed radiologically. We present such a case with its spinal computed tomography findings, the second such case reported in the radiology literature.