Intracerebral abscess is a life-threatening condition for which there are no current, widely accepted neurosurgical management guidelines. The purpose of this study was to investigate Canadian practice patterns for the medical and surgical management of primary, recurrent, and multiple intracerebral abscesses.

A self-administered, cross-sectional, electronic survey was distributed to active staff and resident members of the Canadian Neurosurgical Society and Canadian Neurosurgery Research Collaborative. Responses between subgroups were analyzed using the Chi-square test.

In total, 101 respondents (57.7%) completed the survey. The majority (60.0%) were staff neurosurgeons working in an academic, adult care setting (80%). We identified a consensus that abscesses >2.5 cm in diameter should be considered for surgical intervention. The majority of respondents were in favor of excising an intracerebral abscess over performing aspiration if located superficially in non-eloquent cortex (60.4%), located in the posterior fossa (65.4%), or causing mass effect leading to herniation (75.3%). The majority of respondents were in favor of reoperation for recurrent abscesses if measuring greater than 2.5 cm, associated with progressive neurological deterioration, the index operation was an aspiration and did not include resection of the abscess capsule, and if the recurrence occurred despite prior surgery combined with maximal antibiotic therapy. There was no consensus on the use of topical intraoperative antibiotics.

This survey demonstrated heterogeneity in the medical and surgical management of primary, recurrent, and multiple brain abscesses among Canadian neurosurgery attending staff and residents.1

Calcifying pseudoneoplasm of the neuraxis (CAPNON) is a rare tumor-like lesion with unknown pathogenesis. It is likely under-reported due to diagnostic challenges including the nonspecific radiographic features, lack of diagnostic markers, and often asymptomatic nature of the lesions.

We performed detailed examination of 11 CAPNON specimens diagnosed by histopathology, with the help of electron microscopy and immunohistochemistry.

Electron microscopy revealed the presence of fibrillary materials consistent with neurofilaments. In addition to some entrapped axons at the periphery of CAPNONs, we discovered that all specimens stained positive for neurofilament-light (NF-L) within the granular amorphous cores, but not neurofilament-phosphorylated (NF-p). CAPNONs also showed variable infiltration of CD8+ T-cells and a decreased ratio of CD4/CD8+ T-cells, suggesting an immune-mediated process in the pathogenesis of CAPNON.

NF-L and CD4/CD8 immunostains may serve as diagnostic markers for CAPNON and shed light on its pathogenesis.

Calcifying pseudoneoplasm of the neuraxis (CAPNON) is a rare tumefactive lesion. CAPNONs can mimic calcified meningiomas at the skull base.

Here, we report two cases of CAPNON and present a systematic review of the literature on skull base CAPNONs, to compare CAPNONs with calcified meningiomas.

Case 1: A 57-year-old man presented with right-sided lower cranial neuropathies and gait ataxia. He underwent a subtotal resection of a right cerebellopontine angle lesion, with significant improvement of his gait ataxia. However, his cranial neuropathies persisted. Pathological examination of the lesion was diagnostic of CAPNON, with the entrapped nerve fibers identified at the periphery of the lesion, correlating with the patient’s cranial neuropathy. Case 2: A 70-year-old man presented with progressive headache, gait difficulty, and cognitive impairment. He underwent a frontotemporal craniotomy for a near-total resection of his right basal frontal CAPNON. He remained neurologically stable 7 years after the initial resection without evidence of disease recurrence. We analyzed 24 reported CAPNONs at the skull base in our systematic review of the literature. Cranial neuropathies were present in 11 (45.8%) patients. Outcomes regarding cranial neuropathies were documented in six patients: two had sacrifice of the nerve function with surgical approaches and four had persistent cranial neuropathies.

While CAPNON can radiologically and grossly mimic calcified meningiomas, they are two distinctly different pathologies. CAPNONs located at the skull base are commonly associated with cranial neuropathies, which may be difficult to reverse despite surgical intervention.

The objective of this study was to assess the adverse health symptoms experienced by adult subjects who were exposed to benzene after a flaring disaster at the BP refinery in Texas City, Texas.

A total of 2162 adults aged 18 years or older and exposed to benzene were included. Using the patients’ medical charts, we collected and analyzed data on health complaints as well as the patients’ serum levels of beta-2-microglobulin and urinary excretion of phenol.

A total of 11,368 health symptom complaints were reported in 2162 adults exposed to benzene. Neurological symptoms occurred most frequently (174%), followed upper respiratory symptoms (115%), cough (31%), painful joints (30%), cardiac symptoms (28%), dermatological symptoms (28%), gastrointestinal symptoms (27%), diarrhea (25%), vision symptoms (21%), and nausea/vomiting (19%). Logistic regression analysis indicated that urinary symptoms (R2=0.65) and painful joints (R2=0.44) were positively associated with increasing age in benzene-exposed subjects.

Adult subjects exposed to benzene experience a range of adverse health symptoms and an altered profile of urinary phenol, thus indicating they are at high risk of developing serious future health complications. (Disaster Med Public Health Preparedness. 2018;12:232–240)

To examine the adverse effects of benzene exposure in adults from a prolonged flaring disaster at the BP refinery in Texas City, Texas.

Adults aged 18 years and older who had been exposed and unexposed to benzene were included. We reviewed medical charts and compared measures of white blood cells (WBCs), platelets, hemoglobin, hematocrit, blood urea nitrogen (BUN), creatinine, alkaline phosphatase (ALP), aspartate amino transferase (AST), and alanine amino transferase (ALT) in exposed and unexposed adults.

Records from 2213 adults (benzene exposed, n=1826; unexposed, n=387) were reviewed. Benzene-exposed subjects had significantly higher WBC counts (7.9±2.3 vs 6.8±1.6×103 per µL, P=0.0000) and platelet counts (270.8±60.9 vs 242.5±53.7×103 per µL, P=0.0000) than did the unexposed subjects. Serum creatinine levels were also significantly higher in the exposed group than in the unexposed group (1.0±0.2 vs 0.8±0.2 mg/dL, P=0.000). Serum levels of ALP were significantly higher in the exposed subjects than in the unexposed subjects (82.1±15.6 vs 71.8±8.2 IU/L, P=0.000). Similarly, benzene-exposed subjects had significantly higher levels of AST (26.2±6.4 vs 19.7±5.3 IU/L, P=0.000) and ALT (30.6±10.8 vs 20.9±9.6 IU/L, P=0.000) than in those unexposed to benzene.

Benzene exposure resulted in significant alterations in hematologic and liver profiles in adults. (Disaster Med Public Health Preparedness. 2016;10:233–239)

Despite the growing recognition for analgesic needs in post-craniotomy patients, this remains a poorly studied area in neurological surgery. The class and regimen of analgesia that is most suitable for these patients remains controversial. The objective of this study is to examine the current beliefs and practices of Canadian neurosurgeons when managing post-craniotomy pain.

A survey was sent to all practicing Canadian neurosurgeons to examine the following aspects of analgesia in craniotomy patients: type of analgesics used, common side effects encountered, satisfaction with current regimen and the rationale for their practice.

Of 156 potential respondents, 103 neurosurgeons (66%) completed the survey. Codeine (59%) was the most prescribed firstline analgesic followed by morphine (38%). The use of a second-line opioid was significantly higher among codeine prescribers compared to morphine, 53% compared to 28% (p < 0.001). Nausea, constipation and neurologic depression were reported as common side effects by 76%, 66% and 27% of respondents respectively. Of the respondents, 90% reported a high level of satisfaction with their current choice of analgesia; nonetheless, they predominantly described their practice as personal preference or protocol driven rather than evidence-based.

Codeine - a weak opioid - is the most common first-line analgesic prescribed to craniotomy patients. This practice is associated with substantially increased reliance on potent opioids for rescue analgesia. Whether novel regimens can provide optimal pain control while minimizing neurologic and gastrointestinal side effects remains to be addressed by future trials.

To survey neurosurgical practices in the treatment of chronic and subacute subdural hematoma in the Canadian adult population.

We developed and administered a questionnaire to Canadian Neurosurgeons with questions relating to the management of chronic and subacute subdural hematoma. Our sampling frame included all neurosurgery members of the Canadian Neurosurgical Society.

Of 158 questionnaires, 120 were returned (response rate = 76%). The respondents were neurosurgeons with primarily adult clinical practices (108/120). Surgeons preferred one and two burr-hole craniostomy to craniotomy or twist-drill craniostomy as the procedure of choice for initial treatment of subdural hematoma (35.5% vs 49.5% vs 4.7% vs 9.3%, respectively). Craniotomy and two burr-holes were preferred for recurrent subdural hematomas (43.3% and 35.1%, respectively). Surgeons preferred irrigation of the subdural cavity (79.6%), use of a subdural drain (80.6%), and no use of anti-convulsants or corticosteroids (82.1% and 86.6%, respectively). We identified a lack of consensus with keeping patients supine following surgery and post-operative antibiotic use.

Our survey has identified variations in practice patterns among Canadian Neurosurgeons with respect to treatment of subacute or chronic subdural hematoma (SDH). Our findings support the need for further prospective studies and clinical trials to resolve areas of discrepancies in clinical management and hence, standardize treatment regimens.

Evaluate the incidence, neurologic morbidity, and mortality of patients with Terson syndrome.

Consecutive patients admitted to the Hamilton General Hospital from May 2012 to May 2013 with a diagnosis of spontaneous subarachnoid hemorrhage (SAH) were recruited. Funduscopic examinations were performed under pharmacological mydriasis. Outcome measures included: (1) the presence or absence of Terson syndrome; (2) The Glasgow Coma Scale (GCS), Hunt and Hess scale (H&H), and SAH Fisher score upon admission to the hospital; (3) the modified Rankin score upon discharge; and (4) and all-cause mortality.

Forty-six patients were included and 10 had Terson syndrome (21%). The median H&H, GCS, and Fisher scores were 4, 6.5, and 4.0 for patients with Terson syndrome vs. 2, 14, and 3 for patients without Terson syndrome (p=0.0032, 0.0052, and 0.031), respectively. The median Rankin score was 6 for patients with Terson syndrome vs. 3.5 for patients without Terson syndrome (p=0.0019). The odds of all-cause mortality with Terson syndrome vs. no Terson syndrome was 12: 1 (95% confidence interval 2.33-61.7), p =0.003. Only four of the 10 patients with Terson syndrome survived.

Based on this study, approximately one-fifth of patients admitted to the hospital with a spontaneous SAH could have Terson syndrome. Patients with Terson syndrome have significantly worse GCS and H&H scores upon admission to the hospital, lower modified Rankin scores upon discharge, and greater mortality. Thus, Terson syndrome is not rare among patients with SAH and carries a worse prognosis.

Cauda equina syndrome (CES) is a feared complication of lumbar disc herniation. It is generally accepted that CES requires decompression within 6 hours of symptom onset, but this time goal is rarely met, and the relative benefit of delayed decompression on functional status and quality of life (QOL) remains unknown. The study objective was to describe the functional status and quality of life outcomes for patients who undergo delayed surgical decompression for CES.

Patients with CES who underwent decompression of a herniated lumbar disc during a 10-year period were assessed at hospital discharge and at least 4 months after the procedure. Evaluation of functional outcomes was based on a previously validated scale and QOL outcomes on the Medical Outcomes Study 36-item Short-Form Health Survey (SF-36) questionnaire.

During the study period, 1100 patients with herniated discs were identified, and 14 underwent surgical decompression for CES. All 14 had had symptoms for more than 38 hours before surgery. Ten patients were available for long-term follow-up. There was a strong correlation between long CES symptom duration and poor functional outcome: of 8 patients with symptoms for less than 10 days before decompression (range, 1.6–7.5 d), all had good functional outcomes. The 2 patients with more prolonged symptoms (10.6 and 14.2 d) had poor outcomes. SF-36 scores demonstrated declines in physical roles (p = 0.03), social function (p = 0.03) and increased pain (p = 0.003) compared with population norms. Correlation between SF-36 domain scores and CES symptom duration failed to achieve statistical significance, perhaps because of small sample size.

Patients who undergo delayed decompression for CES have increased pain and impaired social and physical function. Longer delays correlate with worse functional outcomes. Beyond 24 hours, decompression delay may be associated with a poorer quality of life but, because of the rarity of CES, the sample size in this study was too small to provide definitive conclusions. Since no patients underwent surgery within 38.4 hours of symptoms, it is not possible to comment on the importance of emergent decompression in early presenters.