Ian B. Ross

Nocardia asteroides cerebral abscess in immunocompetent hosts: report of three cases and review of surgical recommendations

BACKGROUND Nocardia asteroides cerebral abscesses are rare intracranial lesions. They account for only 2% of brain abscesses. Existing literature takes the form of anecdotal reports, small case series, and retrospective studies. An optimal treatment approach has not been established. However, there is evidence that the size of the lesion and clinical and immune status of the patient are relevant to surgical decision making. METHODS Three recent cases are presented and the existing literature is reviewed. RESULTS The outcome in all three cases was satisfactory. Although the currently recommended neurosurgical management protocols were followed, one patient had a prolonged course, which may have been shortened had an earlier biopsy of the cerebral lesion been performed. CONCLUSIONS The surgical approach to suspected Nocardia spp. cerebral abscesses has recently become less aggressive. A more aggressive approach than that currently preferred for suspected Nocardia spp. cerebral abscesses may be appropriate. Earlier biopsy of lesions to achieve specific identification and anti-microbial sensitivity profiles is suggested even in cases where an extracranial focus of infection is found. Delays in obtaining a biopsy may lead to non-specific or unhelpful results that may prolong the course in hospital and jeopardize the outcome.

Periodontoid Synovial Cyst Causing Cervico-medullary Compression

BACKGROUND Periodontoid synovial cysts are rare lesions which may produce symptomatic cervico-medullary compression. METHOD We report such a patient, whose progressive neurological deterioration required surgical treatment by transoral odontoidectomy and decompression. RESULTS The diagnostic and theraputic interventions are described, including a lumbar puncture which precipitated a transient loss of consciousness and respiratory arrest. Surgery achieved clinical improvement, without complications or need for operative stablization. Detailed neuropathology is presented, as well as a literature review. CONCLUSION Appropriate neuroradiological assessment is required in patients with suspected cervico-medullary compression, and symptomatic periodontoid synovial cysts may respond well to transoral surgical decompression.

Carotid endarterectomy results in the early years of practice

BACKGROUND Newly qualified surgeons, as well as their referring physicians, are understandably anxious when dangerous surgery is contemplated. Carotid endarterectomy (CEA), which requires a low morbidity/mortality rate to be successful, is especially problematic in this realm. There is a paucity of literature indicating the results that can be expected when a less-experienced surgeon is asked to perform this procedure. As the volume of CEA surgery is expected to decrease in the future with improvements in endovascular techniques, there will be fewer highly experienced CEA surgeons around. METHODS We studied the first consecutive, prospectively recorded 100 CEAs performed by each of two newly qualified surgeons (200 total) between January 1993 and May 1998. Standard technique was used and all cases were done under general anesthesia. The only difference in technique was the more liberal use of shunting and protamine by one individual. RESULTS There were no significant differences in the patient demographics between the two surgeons. Seventy-five percent of the cases harbored symptomatic stenoses. An overall combined stroke/mortality rate of 5.5% was observed. The rate in those operated on for symptomatic stenosis (n = 150) was 6% while it was 4% for those with asymptomatic pathology. There were no significant differences in outcome between the two surgeons. The average stroke/mortality rate in the first 50 cases for each surgeon was 7%, as opposed to 4% for the second 50 cases. CONCLUSIONS These data indicate that less-experienced individuals can perform this procedure with good results.

Stereotactic radiosurgery for acoustic neuroma: a Canadian perspective.

Stereotactically delivered radiation is now an accepted treatment for patients with acoustic neuroma. In some cases, patient preference may be the reason for its selection, while in others neurosurgeons may select it for patients who are elderly or have significant risk factors for conventional surgery. The majority of patients with acoustic neuroma treatment with stereotactic radiosurgery have been treated with the Gamma Knife, with follow ups of over 25 years in some instances. Other radiosurgery modalities utilizing the linear accelerator have been developed and appear promising, but there is no long-term follow up. Canada does not possess a Gamma Knife facility, and its government-funded hospital and medical insurance agencies have made it difficult for patients to obtain reimbursement for Gamma Knife treatments in other countries. We review the literature to date on the various forms of radiation treatment for acoustic neuroma and discuss the current issues facing physicians and patients in Canada who wish to obtain their treatment of choice.

Delayed Neurologic Complications of Vertebral Bone Cement Injections

paradigms. In some instances, they have enabled surgeons to perform procedures that would otherwise be impossible. Elsewhere, they have minimized potential morbidity. In the field of neurological surgery, deep brain stimulation would fit in the former category and endovascular treatment of cerebral aneurysms the latter. Reinforcement of pathological fractures of the vertebral axis, usually with polymethyl methacrylate (PMMA) injection, provides instant fixation of unstable and painful fractures and is usually well tolerated by patients. This technique, performed either as vertebroplasty or kyphoplasty, affords both of the aforementioned advantages and has therefore been a welcome addition to the surgical armamentarium. Significant improvement in pain is reported in about 90% of patients after PMMA vertebral body embolization for osteoporotic compression fractures1. Benefit appears to be durable, as evidenced by a study with a mean follow-up of 48 months2. The potential for complications, however, is not negligible. These include pulmonary venous embolism and spinal cord or nerve root compression from aberrant PMMA. The literature suggests that these complications are rare1. Symptomatic pulmonary embolism typically manifests itself rapidly and, similarily, one would expect significant PMMA in the spinal canal to cause symptoms right after the injection. Neurological problems associated with PMMA vertebral injections may, however, manifest themselves at a later date3. It is important that practitioners of this technique recognize when a patient is having an adverse event. We report here two patients with delayed symptomatic lesions that were, eventually, treated surgically and improved clinically.