Elective stenting of symptomatic basilar artery stenosis.

BACKGROUND AND PURPOSE: Percutaneous angioplasty of the intracranial arteries still carries the risk of dissection, with acute closure and embolization. Stenting has been shown to improve the safety and durability of angioplasty in every circulatory bed in which it has been applied. However, stenting of the intracranial arteries has been limited by the availability of stents that can be reliably deployed intracranially. METHODS: Twelve patients underwent elective stenting of the basilar artery after episodes of vertebrobasilar ischemia. In all patients, either medical therapy had failed or the patient had a contraindication for long-term anticoagulation. Information from independent neurological examinations, quantitative angiography, and clinical follow-up was collected. Differences between pretreatment and posttreatment degree of stenoses were subjected to 1-way ANOVA for repeated measures. RESULTS: There were 10 men and 2 women, all white, aged 40 to 82 years (mean age, 62.6 years). Stent placement was successful in all patients, leading to statistically significant changes in the degree of stenosis, from 71. 4% (range, 53% to 90%) to 10.3% (range, 0% to 36%) (P<0.0001). There were no deaths, stent thromboses, perforations, ruptures, or myocardial infarctions. Clinical follow-up was available for 0.5 to 16 months (mean, 5.9 months). One patient had nonspecific symptoms, and another had a transient ischemic attack. All other patients remained asymptomatic. CONCLUSIONS: Elective stenting of the basilar artery is feasible, with minimal risk to the patient. Its impact on long-term stroke prevention and its durability are unknown and will require further study.

Neuroendovascular rescue. Nonthrombolytic approach to acute brain ischemia.

The field of neuroendovascular therapy is rapidly growing. New technology and operators' expertise is developing at a pace that will make this discipline progressively more available and successful. For the intensive care of patients who have acute brain ischemia, new techniques of recanalizing occluded arteries are progressively being introduced. Thus, the concept of neuroendovascular rescue has gone beyond the use of thrombolytic drugs, expanding our capability to restore flow to ischemic brain tissue after prolonged therapeutic windows. It is important for the interventionalist and the intensivist to work closely together to guarantee the most favorable outcome possible.

Endovascular therapy of traumatic carotid-cavernous fistulas.

Traumatic carotid-cavernous fistulas (CCF) are capable of causing a large variety of signs and symptoms, including visual loss, glaucoma, chemosis, exophthalmos, and orbital cranial nerve palsies. The high pressure in the veins that normally drain the globe can cause them to engorge and produce local compression of adjacent structures. At present, endovascular closure of the fistula is the treatment of choice, particularly in patients with progressive neurologic deterioration. Endovascular repair of CCF most commonly involves the use of detachable balloons, although coils are also used. Effective closure of the fistula leads to rapid resolution of the symptoms.

The safety of OP-1 for lumbar fusion with decompression-- a canine study.

OBJECTIVE: Bone morphogenetic proteins can serve as adjuncts to autologous bone to achieve bony fusion, and recombinant BMPs such as osteogenic protein-1 (OP-1) have the potential to replace autologous bone altogether as fusion substrate. However, relatively little is known about the safety of OP-1 for spinal fusion procedures. This study examined the effects of OP-1 intentionally placed in the subarachnoid space following thecal sac decompression, and used as graft substrate in a canine dorsolateral lumbar spine fusion model. METHODS: Lumbar decompression with dorsolateral fusion was performed on 30 canines. The dura was opened to simulate an intraoperative rent and OP-1 was placed in the subarachnoid space and in the fusion bed. Animals were sacrificed after 16 weeks and the spines were examined manually, radiographically and pathologically. RESULTS: All animals treated with OP-1 developed new bone in the subarachnoid space. This bone compressed the spinal cord, but no clinical or pathological features of neurotoxicity were noted. Mild spinal stenosis was noted at the site of dural decompression in the OP-1 treated animals. Over 80% of animals treated with OP-1 developed fusion as assessed by palpation (52% by CT criteria), while only 25% of control animals fused. CONCLUSIONS: Recombinant human OP-1 is effective at promoting fusion in a canine dorsolateral lumbar spine fusion model. However, bone growth can occur over exposed, decompressed dura, and it can form in the subdural and subarachnoid spaces. The use of OP-1 as an adjunct to spinal fusion appears to have merit, but its use must be carefully controlled to avoid unwanted bone formation and subsequent neural compression.

Neurological monitoring during carotid artery stenting: the Duck Squeezing Test.

PURPOSE: To examine the usefulness of a novel method for neurological monitoring during carotid artery stenting (CAS). METHODS: The records of patients who underwent elective CAS between June 1996 and October 1998 were reviewed to identify those who had neurological changes during the procedure. We examined whether the neurological change had been detected by a change in the ability of the patient to respond to predetermined commands involving a small rubber duck placed in the contralateral hand. RESULTS: hundred seventy patients (320 vessels) underwent monitoring using the Duck Squeezing Test; 10 suffered neurological events during the procedure. Four of these were transient and temporally related to balloon inflation. Another 6 were tentatively ascribed to distal embolism. All instances were accompanied by a change in the patient's ability to perform the Duck Squeezing Test, which allowed the identification of the abnormal clinical situation. In addition, there were 4 false-positive tests secondary to the patient accidentally dropping the rubber duck. CONCLUSIONS: The Duck Squeezing Test is a sensitive and specific method for monitoring patients during elective CAS. Its practical applicability is based on sound neurophysiological concepts, which underscore the clinical importance of the test.

Cerebrospinal fluid fistula: detection with MR cisternography.

PURPOSE: Our goal was to assess the role of MR cisternography in the examination of patients with suspected CSF rhinorrhea. METHODS: MR cisternography was performed as a heavily T2-weighted fast spin-echo study with fat suppression and video reversal of the images in 37 patients over a 3-year interval. Twenty-four of the patients subsequently had exploratory surgery for fistula. Statistical analysis of the surgical results was compared with the findings at MR cisternography. RESULTS: MR cisternography showed significant correlation with surgical findings, with sensitivity, specificity, and accuracy of 0.87, 0.57, and 0.78, respectively. CONCLUSION: MR cisternography proved to be an accurate diagnostic imaging technique in the evaluation of suspected CSF rhinorrhea.

Computed tomography of posterior fracture-dislocations of the shoulder: case reports.

Computed tomographic (CT) evaluation of seven posterior shoulder dislocations in five patients is reported. Computed tomography provided better visualization of the trough fracture in the humeral head than did conventional x-ray films or tomography. It also demonstrated fracture fragments not seen on conventional roentgenograms. The two cases of bilateral dislocation and one case of unilateral dislocation were caused by seizures. The two other cases of unilateral dislocation were caused by trauma.