Sequential outer table craniotomy a in hyperossified meningioma. Technical note

Thoracic psammomatous spinal meningioma with osseous metaplasia: A very rare case report

Thoracic spinal psammomatous meningioma is a rare subtype of meningioma. Among diverse types of mesenchymal differentiation, osseous metaplasia is found to be still rarer. We are presenting a new case of thoracic psammomatous spinal meningioma with osseous metaplasia in a middle aged female which that gives a sense of cancellous bone in the spinal canal. To conclude, meningiomas with osseous metaplasia are very rare tumors that complicate the surgical removal in certain cases. Ossification, if predicted prior to operation with computed tomography reconstruction, makes planning of removal easier. In our case, maintained cerebrospinal fluid spaces despite hard consistency of tumor made its removal easier once cerebrospinal fluid was drained. We have submitted this article because it is very rare and curable pathology and preoperative diagnosis helps in prevention of neurological injury during its excision.

Evaluation of drill-induced heat transmission in an orbital model

PURPOSE

To evaluate the influence of saline irrigation on temperature rise in orbit bones and the optic canal during high-speed drilling.

METHODS

An experimental study measuring temperature rise in an orbit during high-speed drilling was conducted. The orbital rims, sphenoid bone, and optic canals of 6 unpreserved caprine orbits were drilled with a 3.1-mm diamond drill bit at 35,000 rpm. Each orbit was divided into groups receiving no irrigation, continuous or intermittent external irrigation at 5-second intervals during the procedures. The temperature rise of each site was compared among the groups, along with the duration of drilling.

RESULTS

The mean (± SD) temperature elevation in the optic canal without irrigation was 2.38 °C (± 0.30 °C). This was significantly higher than in the canals receiving intermittent irrigation (0.90 °C ± 0.40 °C; p < 0.001) and continuous irrigation (0.66 °C ± 0.40 °C; p < 0.001). Mean temperature rise in the orbital rim without irrigation was significantly higher (3.51 °C ± 1.30 °C) than with intermittent (1.05 °C ± 0.31 °C; p < 0.001) and continuous (0.98 °C ± 0.61 °C; p < 0.001) irrigation. Mean temperature rise in the sphenoid was significantly higher (3.68 °C ± 1.66 °C) without irrigation than with intermittent (1.36 °C ± 1.17 °C; p = 0.005) and continuous (0.90 °C ± 0.33 °C; p < 0.001) irrigation. There were no statistically significant differences between any of the intermittent and continuous irrigation groups.

CONCLUSIONS

The presence of either continuous or intermittent irrigation during orbital drilling procedures significantly decreases the temperature rise in the region adjacent to the surgical site. This has important implications for surgical technique when operating near the optic canal. Further studies regarding potential effects on the optic nerve are warranted.