A novel cognitive neurosurgery approach for supramaximal resection of non-dominant precuneal gliomas: a case report.

Despite mounting evidence pointing to the contrary, classical neurosurgery presumes many cerebral regions are non-eloquent, and therefore, their excision is possible and safe. This is the case of the precuneus and posterior cingulate, two interacting hubs engaged during various cognitive functions, including reflective self-awareness; visuospatial and sensorimotor processing; and processing social cues. This inseparable duo ensures the cortico-subcortical connectivity that underlies these processes. An adult presenting a right precuneal low-grade glioma invading the posterior cingulum underwent awake craniotomy with direct electrical stimulation (DES). A supramaximal resection was achieved after locating the superior longitudinal fasciculus II. During surgery, we found sites of positive stimulation for line bisection and mentalizing tests that enabled the identification of surgical corridors and boundaries for lesion resection. When post-processing the intraoperative recordings, we further identified areas that positively responded to DES during the trail-making and mentalizing tests. In addition, a clear worsening of the patient's self-assessment ability was observed throughout the surgery. An awake cognitive neurosurgery approach allowed supramaximal resection by reaching the cortico-subcortical functional limits. The mapping of complex functions such as social cognition and self-awareness is key to preserving patients' postoperative cognitive health by maximizing the ability to resect the lesion and surrounding areas.

Surgical results and complications in a series of 71 consecutive cervical spondylotic corpectomies.

BACKGROUND: Cervical corpectomy is a common procedure in spondylosis. It is normally a well-tolerated surgery and clinical improvement is widely described. However, it is associated with potential risky complications (subsidence, clinical deterioration, vertebral artery injury...); thus, a judicious surgical indication and a good technique are required. METHODS: We revised retrospectively the clinical evolution and complications of 71 spondylotic corpectomies in a series of 100 consecutive patients operated on due to different ethiological causes from January 2001 to September 2007 at our hospital. RESULTS: Among the 71 cases, a single-level corpectomy was performed in 46 cases and a two level in 25. The graft we used was a titanium mesh filled with bone from the removed vertebra in 69 cases and a telescopic cage in two additional cases. We stabilized the construction with a locking plate. The presurgical clinical status of patients, according to the Nurick grading scale was as follows: 30 patients were grade 0, 12 were grade 1, eight were grade 2, 14 were grade 3, five were grade 4 and two were grade 5. After decompression, 41 patients were considered cured, three were grade 1, seven were grade 2, 11 were grade 3, seven were grade 4 and one was grade 5. One patient died in the postoperative period. Globally, 44 (62%) patients achieved good or excellent results (grades 0-1), 15 (21%) remained as previously (grade >1), six (8%) improved partially and five (7%) worsened. Forty (95%) grades 0 and 1 patients became cured, and four (50%), four (31%) and two (28%) grades 2, 3 and 4-5, respectively, experienced a postsurgical improvement. Significant complications occurred in 18 (25%) patients. The most significant were: hardware failure (n = 7), subsidence in five cases (one required intervention) and incorrect screw placement in two (one required intervention); permanent dysphagia (n = 4) and dysphonia (n = 1); postsurgical neurological worsening in three cases (two improved and one remained grade 4); vertebral artery injury in one case; and an urgent evacuation of a prevertebral hematoma. One patient died due to respiratory disturbances. CONCLUSIONS: Cervical corpectomy is efficient for spinal cord decompression, especially when anterior components (disk osteophyte, OPLL...) bulge in the spinal cord. A three or more level corpectomy was not considered in this series since they may be associated to high rate morbidity. We found that this decompression led to better clinical results in patient grades 0 and 1 and to poorer results as myelopathy progressed. Among complications, subsidence was the most frequent specific one, but since it was rarely associated with symptoms, the majority of patients were successfully treated conservatively.