Navigating the calvaria with mobile mixed reality-based neurosurgical planning: how feasible are smartphone applications as a craniotomy guide?

OBJECTIVE: Virtual simulation and imaging systems have evolved as advanced products of computing technology over the years. With advancements in mobile technology, smartphones, and tablets, the quality of display and processing speed have gradually improved, thanks to faster central processing units with higher capacity. Integrating these two technologies into the fields of healthcare and medical education has had a positive impact on surgical training. However, contemporary neurosurgical planning units are expensive and integrated neuronavigation systems in operating rooms require additional accessories. The aim of this study was to investigate the compatibility of smartphone applications in augmented reality (AR)-based craniotomy planning, which can be available even in disadvantaged workplaces with insufficient facilities. METHODS: Thirty patients diagnosed with supratentorial glial tumor and who underwent operations between January 2022 and March 2023 were included in the study. The entire stages of the surgical procedures and the surgical plans were executed with neuronavigation systems. The patient CT scans were reconstructed using software and exported as a 3D figure to an AR-enhanced smartphone application. The evaluation of the application's success was based on the spatial relationship of the AR-based artificial craniotomy to the neuronavigation-based craniotomy, with each AR-based craniotomy scaled from 0 to 3. RESULTS: In the comparison between neuronavigation-based and AR fusion-based craniotomies, 8 of 30 (26.6%) patients scored 0 and were considered failed, 6 (20%) scored 1 and were considered ineffective, 7 (23.3%) scored 2 and were considered acceptable, and 9 (30%) scored 3 and were considered favorable. CONCLUSIONS: AR technology has great potential to be a revolutionary milestone of neurosurgical planning, training, and education in the near future. In the authors' opinion, with the necessary legal permissions, there is no obstacle to the integration of surgical technological systems with mobile technology devices such as smartphones and tablets that benefit from their low-budget requirements, wide-range availability, and built-in operating systems.

Evaluation of the Utility of Indocyanine Green Video Angiography in Cerebral Arteriovenous Malformation Surgery.

OBJECTIVE: To assess the utility of intraoperative indocyanine green video angiography (ICG-VA) during microsurgical resection of arteriovenous malformations (AVMs). METHODS: Data of the 24 patients, who were surgically treated for AVM using intraoperative ICG-VA, were reviewed retrospectively. Postoperative digital subtraction angiography (DSA) was performed in all patients before they regained consciousness and became fully awake, and the results were compared with those obtained with intraoperative ICG-VA. A scheduled DSA was performed in all patients in the third, sixth, and 12th postoperative months as well. RESULTS: Authors retrospectively analyzed the records of intraoperative ICG-VA application of all 24 patients. Though the exposures were limited and the image qualities were poor at higher magnification on the surgical microscope within deep surgical fields, the AVM niduses, feeding arteries, draining veins, and their relations to normal vasculature were observed precisely with ICG-VA in all the procedures. Furthermore, the visualization was not qualified enough to identify these pathological vascular structures accurately before evacuating and irrigating the layer of blood clots that obscure the view in patients who presented with hemorrhage. In a patient in our series, a residual nidus in the tail of the caudate nucleus was detected with immediate postoperative DSA which was not revealed by terminal assessment with final intraoperative ICG-VA. CONCLUSIONS: Intraoperative ICG-VA is particularly effective in the identification of the feeder, nidus, and drainer and in the assessment of the flow dynamics of the nidus in cerebral AVM surgery. It may be a quick and safe technique for intraoperative imaging of the angioarchitecture of superficial AVMs, but it may be less helpful for deep-seated lesions. Furthermore, this method alone may not be useful in the identification of residual disease or improvement of the clinical outcomes. DSA has remained the gold standard for confirming AVM obliteration. Despite the technical limitations associated with ICG-VA, a combination of intraoperative ICG-VA and immediate postoperative DSA may advance the safety and efficacy of AVM surgery.

Posterior midline approach to odontoidectomy: A novel method to treat basilar invagination.

Background: Basilar invagination (BI) is a common malformation of the craniocervical region where the odontoid process protrudes into the foramen magnum. Surgery in this region is difficult because of the complex anatomy of the craniocervical junction. Serious life-threatening complications have been observed with previously described approaches. Therefore, we conceived a novel surgical approach that can be implemented by neurosurgeons with different skill levels to facilitate better outcomes. Methods: We describe a new surgical technique for the treatment of BI that we used in two patients in whom cervical myelopathy and direct ventral compression of the cervicomedullary junction were confirmed through clinical and radiological findings. We present the technique of posterior odontoidectomy in a step-by-step, didactic, and practical manner with surgical tips and tricks. Results: The resection was completed without intraoperative or postoperative complications in both cases. The patients experienced substantial neurological improvements, and full recovery was observed during the 9-month and 12-month follow-up visits after discharge. Compared with the transoral approach, our technique provides a larger decompression area. Conclusions: We describe a novel method for the treatment of BI that was applied in two patients and suggest that the posterior approach might be a safe and effective method for ventral decompression of the craniocervical junction. Posterior odontoidectomy followed by craniocervical fixation helped achieve complete cervicomedullary decompression.

Intraventricular Hematoma Removal with Combined Drainage Techniques in Patients with High-Grade Subarachnoid Hemorrhage: A Surgical Technique.

AIM: To describe a surgical technique for removal of hematomas in the third ventricle in patients with high-grade aneurysmal subarachnoid hemorrhage (SAH) and report our intraoperative observations and surgical and clinical outcomes. MATERIAL AND METHODS: Ninety-four patients with high-grade aneurysmal subarachnoid hemorrhagic were included in the study. Prior to Sylvian dissection, a ventricular catheter was inserted as soon as possible. After surgical corridor opening and aneurysm clipping, the lamina terminalis (LT) was fenestrated. The free flow of isotonic solution from the back-side open syringe to the distal end of the catheter inside the third ventricle was allowed under gravitational force. The blood clot trapped in the third ventricle was removed through the aperture of the LT by propulsion of blood through the anterior movement of the solution. The procedure was continued until the clearance of solution was observed. RESULTS: The study population consisted of two groups, the combined surgical technique group and the control group, which included patients who underwent operation before the planned study, with 47 patients in each group. The Glasgow Coma, Hunt and Hess, and Fisher scales were used to determine the clinical and radiological severities of the cases. The Modified Rankin Scale was used to evaluate the surgical outcomes at presentation and the 6 < sup > th < /sup > and 12 < sup > th < /sup > postoperative months. CONCLUSION: Our reported surgical technique, which combines ventricular drainage and opening of the LT, will be useful for removing blood clots and blood breakdown products, and recirculating cerebrospinal fluid as much and as soon as possible in high-grade SAH patients with ventricular hemorrhage. Although combining these two well-known procedures as a novel technique does not have any reducing effect on mortality, it may have a significant reducing effect on hydrocephalus and shunt dependency.

Acute hydrocephalus caused by a gelatin-sponge material: a case report.

Third ventricle lesions, especially those located proximally to the foramen of Monro, generally present with obstructive hydrocephalus symptoms. In this report, we present a case with acute obstructive hydrocephalus secondary to a gel-foam material. The patient has previously underwent an endoscopic cystectomy. At postoperative third month, she admitted to our hospital with the complain of headache. Neuroradiological imaging revealed triventricular hydrocephalus. A second endoscopic operation was performed, and a piece of gelatin-sponge material was detected at the level of cerebral aqueduct, which obstructed the flow of cerebrospinal fluid (CSF). The CSF flow was immediately restored after removing this material, and an additional third ventriculostomy was performed.

Is Placing Prophylactic Dural Tenting Sutures a Dogma?

OBJECTIVE: In this study, we investigated if and when dural tenting sutures are necessary during craniotomy. METHODS: Results from 437 patients 18-91 years of age (average, 43.5 years) who underwent supratentorial craniotomy between 2014 and 2019 were evaluated. The patients were categorized into 1 of 3 groups: patients who had at least 3 prophylactic dural tenting sutures placed before opening of the dura (group 1); patients who had at least 3 dural tenting sutures placed after surgery was completed, during closure (group 2); or patients who had no dural tenting sutures (group 3 [control]). All such sutures in groups 1 and 2 were placed in the circumference of the craniotomy and dural junction. No central dural tenting sutures were placed in any of the patients. RESULTS: Among the 437 patients, 344 underwent surgery for the first time and 93 were undergoing a second surgery. Cranial computed tomography imaging was performed for each patient 1 hour, 3 days, and 1 month after surgery. In group 1, 3 patients had a cerebral cortex contusion and 2 patients had acute subdural hematoma after the sutures were placed. In groups 2 and 3, none of the patients had a cerebral cortex contusion or acute subdural hematoma. Fewer complications were observed when dural tenting sutures were placed during postsurgical closure. CONCLUSIONS: Placing dural tenting sutures is an important technique for ensuring hemostasis. However, when not needed, they seem to cause inadvertent complications. As our results suggest, knowing when and where to use them is equally important.