Intraoperative Imaging and Optical Visualization Techniques for Brain Tumor Resection: A Narrative Review.

Advancements in intraoperative visualization and imaging techniques are increasingly central to the success and safety of brain tumor surgery, leading to transformative improvements in patient outcomes. This comprehensive review intricately describes the evolution of conventional and emerging technologies for intraoperative imaging, encompassing the surgical microscope, exoscope, Raman spectroscopy, confocal microscopy, fluorescence-guided surgery, intraoperative ultrasound, magnetic resonance imaging, and computed tomography. We detail how each of these imaging modalities contributes uniquely to the precision, safety, and efficacy of neurosurgical procedures. Despite their substantial benefits, these technologies share common challenges, including difficulties in image interpretation and steep learning curves. Looking forward, innovations in this field are poised to incorporate artificial intelligence, integrated multimodal imaging approaches, and augmented and virtual reality technologies. This rapidly evolving landscape represents fertile ground for future research and technological development, aiming to further elevate surgical precision, safety, and, most critically, patient outcomes in the management of brain tumors.

Vestibular Schwannoma Stereotactic Radiosurgery in Octogenarians: Case Series.

BACKGROUND AND OBJECTIVES: The management of octogenarians with vestibular schwannomas (VS) has received little attention. However, with the increase in octogenarian population, more effort is needed to clarify the value of stereotactic radiosurgery (SRS) in this population. The aim of this study was to evaluate the safety and efficacy of SRS in this patient age group. METHODS: A retrospective study of 62 patients aged 80 years or older who underwent single-session SRS for symptomatic VS during a 35-year interval was performed. The median patient age was 82 years, and 61.3% were male. SRS was performed as planned adjuvant management or for delayed progression after prior partial resection in 5 patients. RESULTS: SRS resulted in a 5-year tumor control rate of 95.6% with a 4.8% risk of adverse radiation effects (ARE). Tumor control was unrelated to patient age, tumor volume, Koos grade, sex, SRS margin dose, or prior surgical management. Four patients underwent additional management including 1 patient with symptomatic progression requiring surgical resection, 2 patients with symptomatic hydrocephalus requiring cerebrospinal fluid diversion, and 1 patient whose tumor-related cyst required delayed cyst aspiration. Three patients developed ARE, including 1 patient with permanent facial weakness (House-Brackmann grade II), 1 who developed trigeminal neuropathy, and 1 who had worsening gait disorder. Six patients had serviceable hearing preservation before SRS, and 2 maintained serviceable hearing preservation after 4 years. A total of 44 (71%) patients died at an interval ranging from 6 to 244 months after SRS. CONCLUSION: SRS resulted in tumor and symptom control in most octogenarian patients with VS.

Delayed hardware complication after lateral retroperitoneal lumbar surgery: an unusual case of painless hematuria.

Lateral approaches to the spine are becoming increasingly popular methods for decompression, restoration of alignment, and arthrodesis. Although individual cases of intraoperative injuries to the renal vasculature and the ureters have been documented as rare complications of lateral approaches to the spine, the authors report the first known case of postoperative renal injury due to the delayed extrusion of the screw of a lateral plate/screw construct directly into the renal parenchyma. The migration of the screw from the L1 vertebra into the superior pole of the left kidney occurred nearly 5 years after the index procedure, and presented as painless hematuria. A traditional left-sided retroperitoneal approach had been used at the time of the initial surgery, and the same exposure was used to remove the hardware, which was done in conjunction with general surgery and urology.

Activation of canonical Wnt/ß-catenin signaling stimulates proliferation in neuromasts in the zebrafish posterior lateral line.

BACKGROUND: The posterior lateral line in zebrafish develops from a migrating primordium that deposits clusters of cells that differentiate into neuromasts at regular intervals along the trunk. The deposition of these neuromasts is known to be coordinated by Wnt and FGF signals that control the proliferation, migration, and organization of the primordium. However, little is known about the control of proliferation in the neuromasts following their deposition. RESULTS: We show that pharmacological activation of the Wnt/ß-catenin signaling pathway with 1-azakenpaullone upregulates proliferation in neuromasts post-deposition. This results in increased size of the neuromasts and overproduction of sensory hair cells. We also show that activation of Wnt signaling returns already quiescent supporting cells to a proliferative state in mature neuromasts. Additionally, activation of Wnt signaling increases the number of supporting cells that return to the cell cycle in response to hair cell damage and the number of regenerated hair cells. Finally, we show that inhibition of Wnt signaling by overexpression of dkk1b suppresses proliferation during both differentiation and regeneration. CONCLUSIONS: These data suggest that Wnt/ß-catenin signaling is both necessary and sufficient for the control of proliferation of lateral line progenitors during development, ongoing growth of the neuromasts, and hair cell regeneration.