Search

Background Surgical treatment of ventral and ventrolateral lesions of the craniocervical junction are among the most challenging neurosurgical pathologies to treat. Three surgical techniques, the far lateral approach (and its variations), the anterolateral approach, and the endoscopic far medial approach can be used to approach and resect lesions in this area. Objective The aim of the study is to examine the surgical anatomy of three skull base approaches to the craniocervical junction and review surgical cases to better understand the indications and possible complications for each of these approaches. Methods Cadaveric dissections with standard microsurgical and endoscopic instruments were performed for each of the three surgical approaches, and key steps and surgically relevant anatomy were documented. Six patients with appropriate pre-, post-, and intraoperative imaging and video documentation are presented and discussed accordingly. Results Based on our institutional experience, all three approaches can be utilized to safely and effectively approach a wide variety of neoplastic and vascular pathology. Unique anatomical characteristics, lesion morphology and size, and tumor biology should all be considered when determining the optimal approach. Conclusion Preoperative assessment of surgical corridors with 3D illustrations helps to define the best surgical corridor. 360 degree knowledge of the anatomy of craniovertebral junction allows safe surgical approach and treatment of ventral and ventrolateral located lesions using one of the three approaches. [ABSTRACT FROM AUTHOR]

Background Endoscopic endonasal skull base reconstructions have been associated with postoperative cerebrospinal fluid (CSF) leaks. Objective A repair protocol for endoscopic endonasal skull base reconstruction is presented with the objective of decreasing the overall leak rate. Methods A total of 180 endoscopic endonasal skull base reconstructions were reviewed. Reconstructions were classified I to IV according to the reconstruction method, determined by severity of intraoperatively encountered CSF leaks for types I to III, and planned preoperatively for type IVs, which required nasoseptal flap. Results A total of 11 patients(6%) had postoperative leaks: 0 in type I (0%), 2 in type II (5%), 7 in type III (18%), and 2 (4%) in type IV reconstruction. Type III leak rate was higher than all other reconstructions. Total 31 intraoperative and 16 postoperative lumbar drains were placed. More patients had lumbar drains placed postoperatively for type III and intraoperatively for type IV than all other groups. There were significant overall differences in postoperative CSF leaks and lumbar drain placement between the four reconstruction types. No patient with type III reconstruction and intraoperative lumbar drain had postoperative CSF leak. Conclusions A repair protocol for endoscopic endonasal reconstructions determined by intraoperative CSF leak and preoperative planning minimizes unnecessary repair materials and additional morbidity. Our experience leads to a routine prophylactic lumbar drain placement in all type III leak and reconstructions. We also favor the type III reconstruction for minor intraoperative leaks, and a more generous use of type IV reconstructions in expectation of significant intraoperative CSF leak. The option of rescue flap technique in type III leaks should be strongly considered. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Intraoperative neuromonitoring for intracranial vascular surgery is primarily aimed at detecting early ischemic changes to prevent subsequent infarction. Despite various neurophysiological approaches detection of early and focal ischemic changes remains difficult. This study explores the feasibility and sensitivity of intraoperative monitoring using surface EEG (scalp EEG) and multilobar Electrocorticography (mEcoG) recording during intracranial vascular procedures. Methods: About 21 recordings were acquired in 20 patients undergoing craniotomies for intracranial aneurysms (17), superficial temporal-middle cerebral artery bypass (twice in the same patient) and arteriovenous malformation (2). The recording of scalp EEG (needle electrodes) and EcoG was performed (cupules electrodes) during all of the surgery. Signal was visually analyzed online and using spectral analysis software offline. Results: Good recordings were obtained in all cases, without adding any procedural morbidity. The most common abnormalities on mEcoG were high frequency waves (23–37Hz; HF-β3), which appeared just after vascular occlusion and were occasionally followed by slow waves or burst suppression pattern. This focal pattern was seen in a majority of cases (20/21) on the mEcoG, but only in 4 out of 21 cases on the EEG. Conclusions: Multi-lobe (mEcoG) recording is feasible during craniotomies and detects earlier and more EEG pattern variation than surface EEG monitoring during intracranial vascular manipulations. The authors discuss the high sensitivity of this technique to ischemic changes. Significance: By detecting earlier and more focal changes than scalp EEG, mEcoG may favor during surgery an increase in interactive strategies and reduction of deleterious event. [Copyright &y& Elsevier]

Background Diffusion tensor imaging (DTI) estimates the course and connectivity patterns of white matter tracts. The objective of this study is to evaluate whether findings in the brain stem modify the preoperative surgical trajectory planning or postoperative outcome in patients with brain stem cavernous malformations. Methods Ten patients with symptomatic brainstem cavernous malformation underwent surgical resection. Five patients received preoperative DTI evaluation and the remaining 5 did not. Reconstructed DTI tracts consisted of corticospinal, medial lemnisci, and cerebellar peduncles. The surgical planning and postoperative outcome were evaluated. Results In 5 patients with no preoperative DTI evaluation, surgical planning was based on anatomic landmark and the 2-point technique. The other 5 patients underwent preoperative DTI, and findings were factored into the selection of the surgical approach. In 3 of the 5 cases with DTI evaluation, the 2-point technique suggested a similar trajectory. In the other 2, the DTI findings suggested a different approach to avoid damage to the white matter tract. Two patients in the group with no DTI had immediate postoperative new or worsened deficit, which improved at long-term follow-up. No patient in the DTI group had a new neurologic deficit. Conclusions Compared with the standard magnetic resonance imaging, DTI provided improved visualization of cavernous malformation involvement in eloquent fiber tracts of the brainstem. This additional information might help in selecting a more appropriate surgical trajectory in selected lesions. Larger patient cohorts are needed to assess the effect of this modality in patients’ outcome. [ABSTRACT FROM AUTHOR]