A prospective study on the usefulness of high-resolution intraoperative infrared thermography in intracranial tumors.

Introduction: Infrared thermography (IT) is a non-invasive real-time imaging technique with potential application in different areas of neurosurgery. Despite technological advances in the field, intraoperative IT (IIT) has been an underestimated tool with scarce reports on its usefulness during intracranial tumor resection. We aimed to evaluate the usefulness of high-resolution IIT with static and dynamic thermographic maps for transdural lesion localization, and diagnosis, to assess the extent of resection, and the occurrence of perioperative acute ischemia. Methods: In a prospective study, 15 patients affected by intracranial tumors (six gliomas, four meningiomas, and five brain metastases) were examined with a high-resolution thermographic camera after craniotomy, after dural opening, and at the end of tumor resection. Results: Tumors were transdurally located with 93.3% sensitivity and 100% specificity (p < 0.00001), as well as cortical arteries and veins. Gliomas were consistently hypothermic, while metastases and meningiomas exhibited highly variable thermographic maps on static (p = 0.055) and dynamic (p = 0.015) imaging. Residual tumors revealed non-specific static but characteristic dynamic thermographic maps. Ischemic injuries were significantly hypothermic (p < 0.001). Conclusions: High-resolution IIT is a non-invasive alternative intraoperative imaging method for lesion localization, diagnosis, assessing the extent of tumor resection, and identifying acute ischemia changes with static and dynamic thermographic maps.

Endoscopic Endonasal Approach to Foramen Magnum Meningioma: Two-Dimensional Surgical Video.

Even for the most experienced neurosurgeons, foramen magnum meningiomas represent a surgical challenge owing to their delicate position surrounded by the brainstem, lower cranial nerves, and vertebral arteries. The treatment goal is gross total resection, but choosing the most appropriate approach is crucial. Basically, 3 surgical approaches are commonly used: posterolateral approach (far-lateral), anterolateral approach (extreme-lateral), and posterior midline approach. However, over the years, skull base surgery has evolved from standard open craniotomies to the use of microscopes and, more recently, to the development of endoscopic techniques. The endoscopic endonasal approach (EEA) permits a direct extradural route without brain retraction and shorter postoperative recovery. In contrast to the oral route, the soft palate and retropharyngeal soft tissues are preserved, allowing patients to resume a regular diet on the first postoperative day. Despite the advantages, the EEA is yet not widely used for treating foramen magnum meningiomas, even in cases where EEA use is possible. The EEA is feasible especially in cases with no vascular encasements and with a limited inferior extension allowing minimal manipulation of lower cranial nerves. Care must be taken with tumors with a more lateral and caudal extension (below the tip of the odontoid process), when a far lateral approach may be the best approach. In this surgical Video 1, we present the surgical details with a stepwise narrative of the EEA for ventrolateral foramen magnum meningiomas through an illustrative case of a 48-year-old woman. Institutional informed consent was obtained for surgery and publication of this video.

Predictive Factors for Muscle Injury After Posterior Lumbar Spinal Surgery.

OBJECTIVE: The aims of this study were to evaluate the risk factors for muscle injury in patients undergoing posterior lumbar spinal surgery and the clearance of postoperative biochemical changes following lumbar fusion and secondarily to evaluate the timing for monitoring postoperative biochemical serum levels and potential clinical correlation. METHODS: The study prospectively enrolled 39 patients with degenerative disease of the lumbar spine. Biochemical markers (creatine phosphokinase [CPK], creatinine, and hemoglobin) were analyzed in 5 predefined stages. All relevant clinical data were collected. Rhabdomyolysis (RML) was defined as a postoperative 5-fold increase of the baseline CPK value. RESULTS: Patients from the lumbar fusion group had the highest postoperative CPK ratio. Overall, the rate of RML was 43.6%. CPK and creatinine activity reached their maximum on the first postoperative day in 69.2% and 87.5% of patients, respectively. Lumbar fusion (P = 0.005), surgical time >270 minutes (P = 0.028), and fall in hemoglobin levels >3 g/dL (P = 0.034) were identified as independent factors associated with higher risk of RML. CONCLUSIONS: The risk of RML increases with prolonged and invasive surgery with higher bleeding potential. Knowing the clearance of postoperative biochemical changes permits a standardized strategy with measurements in precise intervals, thereby avoiding unnecessary costs. The clinical significance is still undetermined.