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.

Comparison of Three Surgical Approaches for Frontobasal Meningiomas: Purely Endoscopic Endonasal, Purely Microscopic Bifrontal Transcranial, and Combined Endoscopic and Microscopic Supraorbital Transciliary Approaches.

ABSTRACT: Surgical removal of frontobasal meningiomas (FBMs) can be achieved using different techniques, including endoscopic, transcranial, and combined approaches. The advantages and disadvantages of the outcomes of these approaches should be compared to provide the most convenient surgical treatment to the patient. This study aimed to compare 3 surgical approaches for FBMsin terms of outcomes and determine the superiority of each on the basis of anatomical, surgical, and clinical efficacy. Systematic review was performed to identify studies comparing techniques for the surgical removal of FBMs. Each group included 13 patients; 39 patients with FBMshad undergone surgery. These groups were endoscopic endonasal approach (EEA), microscopic bifrontal transcranial approach (MTA), and endoscopic plus microscopic combined supraorbital transciliary approach (STA) groups. Data on the demographics of patient population, pre- and post-operative neurological examination, tumor properties, imaging studies, and surgical complications were extracted. The mean age at the time of surgery for the patient population was 53.2 years. Among the groups, no statistically significant differences were observed with regard to sex (P = 0.582). The mean follow-up time was 56.7 months. A statistically significant difference was observed in the mean tumor volume among the groups; the MTA group showed the highest mean tumor volume. However, no significant difference was found in the mean tumor volume between EEA and STA groups. Regarding operation duration, the STA group had the shortest operation time (mean = 281.5 minutes), whereas the average surgical duration in MTA group was the longest (mean = 443.8 minutes). The average bleeding volume was highest in the MTA group (mean = 746.2 ml) and lowest in the EEA group (mean = 320.8 ml). Tumor removal was incomplete in three patients (two in the EEA group and one in the MTA group). Recurrence was detected in two cases. One patient with recurrence was operated using the endoscopic surgical approach, whereas the other patient underwent the microscopic bifrontal approach. Post-operative hyposmia/anosmia or decreased olfactory function was the most common complication observed in 5 patients, 2 patients each in the EEA and MTA groups and one in the STA group. The second most common complication was wound infection in one patient in the MTA group and two patients in the STA group (7.7%). Both cerebrospinal fluid (CSF) leakage and meningitis were present in two patients (5.1%), one patient each from the EEA and STA groups. Pre-operative visual disturbances were reported in 13 patients (33.3%), all of which resolved post-operatively No statistical differences were found among the groups. Mortality occurred in a patient in the MTA group (2.6%) caused by cardiac arrest on post-operative day 1. This is the first study comparing the surgical outcomes of three surgical approaches for FBMs. Although recent literature suggests that both endoscopic and transcranial approaches have their own advantages and disadvantages, the authors showed that none of the surgical approaches have obvious superiority over the others with regard to outcomes. Thus, the selection of the ideal surgical approach should be based on surgical experience and tumor characteristics.

Anterior Subcutaneous Transposition With Expanded Polytetrafluoroethylene (ASTEP) for Cubital Tunnel Syndrome: Technical Note.

BACKGROUND: Ulnar nerve entrapment neuropathy at the elbow is the most common upper-extremity entrapment neuropathy after carpal tunnel syndrome. Surgical treatment can be complicated by perineural scarring and fibrosis, which may lead to recurrent symptoms. Expanded polytetrafluoroethylene (ePTFE) is a synthetic polymer with antiadhesive properties. OBJECTIVE: To introduce the operative technique and outcomes of anterior subcutaneous transposition with ePTFE (ASTEP) in primary and recurrent cubital tunnel neuropathy. METHODS: We studied 14 adult patients (11 men, 3 women; mean age, 45 yr) with cubital tunnel neuropathy (10 primary, 4 revision) who underwent surgery with the ASTEP technique between January 2008 and May 2018. Pain, numbness in the fourth/fifth fingers, and weakness of the intrinsic hand muscles were the most common presenting symptoms. Surgical outcomes were assessed using the modified McGowan and Wilson-Krout criteria. RESULTS: The average (± standard deviation) preoperative symptom duration was 12.1 ± 5.2 mo (McGowan Grade 1, n = 5; Grade 2, n = 6; Grade 3, n = 3). No intraoperative or postoperative complications were observed with the ASTEP technique. Postoperative follow-up ranged from 9 mo to 7 yr (mean, 4.3 yr). All 14 patients experienced improvement in or complete resolution of their symptoms after this unique intervention. CONCLUSION: Our novel technique of anterior transposition of the ulnar nerve with ePTFE was safe and highly effective in treating primary and recurrent ulnar nerve entrapment neuropathy at the elbow and represents an alternative to the current techniques.

Modified Inside-outside Occipito-Cervical Plate System: Preliminary Results.

CONTEXT: Internal rigid fixation provides immediate stability of the occipito-cervical (OC) junction for treatment of instability; however, in current practice, the optimal OC junction stabilization method is debatable. AIMS: The aim of this study to test the safety and efficacy of a newly designed modified inside-outside occipito-cervical (MIOOC) plate system for the treatment of instability. SETTINGS AND DESIGN: This was a feasibility study of MIOCC plate system. SUBJECTS AND METHODS: Five male and four female patients with OC instability were treated using MIOOC plate system. Stabilization rate, safety, and efficacy were evaluated radiologically and clinically. RESULTS: Mean age of the patients was 35 ± 11 (range: 22-58) years. Etiology of OC instability included trauma, neoplasm, congenital abnormalities, and iatrogenic. The fusion levels ranged from occiput-C3 to occiput-C6. Mean follow-up duration was 22 ± 10 (range: 6-46) months. There were neither complication nor was there any need for plate revision or screw pullout. Mortality occurred in one patient due to primary malignancy at 6 months; otherwise, no morbidity was observed. During the follow-up, no recurrent subluxation or newly developed instability at adjacent levels occurred. All patients showed a satisfactory union at the most recent follow-up examination. CONCLUSIONS: These preliminary results suggest that the MIOCC plate system is a useful and safe method for providing immediate internal stability of the OC junction. Using a multi-piece plate design in this plate system provided easy implantation and a better interface between plate and OC bones. Further, clinical studies and long-term results are needed to determine the reliability of the MIOOC plate system.

Supraorbital Keyhole Approach: Lessons Learned from 106 Operative Cases.

OBJECTIVE: The supraorbital keyhole approach through an eyebrow incision has been a potentially less invasive approach as an alternative to the standard pterional craniotomy. We aimed to review procedures for anterior and middle cranial fossa lesions and identify lessons learned from addressing various pathologies through this approach. METHODS: We retrospectively reviewed 106 consecutive patients who underwent this approach. We documented patients' age, sex, pathology, clinical results, extent of tumor resection, complications, use of endoscope, and cosmetic results. RESULTS: Our series addressed a variety of pathologies. Male patients accounted for 55% of the cohort and mean age was 51.7 (2-79) years. Notably, 52% of patients underwent resection of extra-axial masses. Gross total resection was achieved in 74.4% of intra-axial lesions according to postoperative imaging. Two (1.9%) patients developed transient ptosis. One (0.9%) patient developed an allergic reaction to titanium. No cerebrospinal fluid fistula or rhinorrhea occurred. Three patients developed temporary diabetes insipidus after resection of parasellar lesions (2 craniopharyngiomas and 1 pituitary adenoma). In 14 patients with olfactory groove meningiomas, 6 (42.8%) suffered from absence or diminished olfaction postoperatively, and 2 (14.2%) developed postoperative anosmia. Five (38.5%) patients underwent a subsequent resection of recurrent glial tumors. Four weeks postoperatively, 95% of patients demonstrated acceptable cosmetic results. Cosmetic results for 6 (5%) patients were unavailable. CONCLUSIONS: The supraorbital keyhole approach may be safely used for various lesions within the anterior and middle cranial fossa. The effectiveness and limitations of this approach and possible complications are discussed. This is a valuable approach for selected patients.

Pure Robotic Surgery for Odontoid Tumor: First Case.

BACKGROUND: Transoral robotic surgery has been used successfully to assist many surgical procedures. Here, we report its first use as pure robotic surgery, applied to excise an odontoid metastatic mass. CASE DESCRIPTION: A 48-year-old woman was hospitalized due to a lesion consistent with metastasis that extended to the pharyngeal constrictor muscles and that had completely destroyed the odontoid bone. Occipitocervical fixation was performed initially, and transoral surgery took place 5 days later. The da Vinci Surgical System Robot was used to resect the tumor. The patient was discharged with a very good general condition. CONCLUSIONS: This article presents the first pure robotic surgery for odontoid. The increasing number of robot-assisted cases will demonstrate the necessity of this evolution in neurosurgery and should accelerate the process.

Comparative analysis of vertebroplasty and kyphoplasty for osteoporotic vertebral compression fractures.

STUDY DESIGN: A retrospective study. PURPOSE: The aim of this study is to compare the efficacy and outcome of vertebroplasty compared with unipedicular and bipedicular kyphoplasty for the treatment of osteoporotic vertebral compression fractures in terms of pain, functional capacity and height restoration rates. OVERVIEW OF LITERATURE: The vertebroplasty procedure was first performed in 1984 for the treatment of a hemangioma at the C2 vertebra. Kyphoplasty was first performed in 1998 and includes vertebral height restoration in addition to using inflation balloons and high-viscosity cement. Both are efficacious, safe and long-lasting procedures. However, controversy still exists about pain relief, improvement in functional capacity, quality of life and height restoration the superiority of these procedures and assessment of appropriate and specific indications of one over the other remains undefined. METHODS: Between 2004 and 2011, 296 patients suffering from osteoporotic vertebral compression fracture underwent 433 vertebroplasty and kyphoplasty procedures. Visual analogue scale (VAS), the Oswestry Disability Index (ODI) and height restoration rates were used to evaluate the results. RESULTS: Mean height restoration rate was 24.16%±1.27% in the vertebroplasty group, 24.25%±1.28% in the unipedicular kyphoplasty group and 37.05%±1.21% in the bipedicular kyphoplasty group. VAS and ODI scores improved all of the groups. CONCLUSIONS: Vertebroplasty and kyphoplasty are both effective in providing pain relief and improvement in functional capacity and quality of life after the procedure, but the bipedicular kyphoplasty procedure has a further advantage in terms of height restoration when compared to unipedicular kyphoplasty and vertebroplasty procedures.

Correlation of matrix metalloproteinase-3 expression with patient age, magnetic resonance imaging and histopathological grade in lumbar disc degeneration.

AIM: The purpose of the present study is to analyze the expression of matrix metalloproteinase-3 (MMP-3), magnetic resonance imaging (MRI) grading and histopathological alterations of the intervertebral disc (IVD) for correlations with each other and with the age, gender and low back pain duration of the patients who had undergone operations for lumbar disc herniation (LDH). MATERIAL AND METHODS: Forty-two patients were admitted to our clinic with signs of LDH and underwent surgery for LDH at 48 IVD levels. In all cases, specimens for histological and immunohistochemical analyses were removed from the IVD space. Lumbar IVD degeneration on MRI of the 48 IVDs from which surgical specimens had been obtained was classified into five grades using the Pfirrmann classification. RESULTS: In the degenerated IVD, the expression of MMP-3, MRI grading and histopathological alterations of the IVD displayed significant correlation. Increased age is closely related with aforementioned alterations. There was no correlation between MMP-3 expression and age, gender and duration of the pain. CONCLUSION: For evaluating and treating IVD degeneration, MRI is a good and non-invasive diagnostic tool to determine the severity of degeneration. MMP-3 may be a therapeutic target of the degenerated IVD.

An unusual sacral osteomyelitis due to an occult anterior sacral meningocele.

OBJECTIVE: We present the extremely rare case of sacral osteomyelitis due to an anterior sacral meningocele (ASM) with fistula to the skin. We also discuss the case's clinical significance and the importance of imaging in diagnosis. METHODS: A 28-year-old female patient was referred to our clinic due to back and hip pain, erythema, and purulent discharge from the right gluteal region. Neurological examination was normal except for pain in the gluteal region. Physical examination revealed a porus lateral to the right gluteal region. Lumbar magnetic resonance imaging (MRI)showed osteomyelitis and a minimal occult sacral meningocele in the anterior sacral region. Contrast-enhanced radiographic imaging clearly showed the fistula tract. The patient underwent surgery via the posterior approach; debridement of the sacral osteomyelitis was performed and the fistula tract toward the skin was closed. RESULTS: She was pain free after surgery. There were no postoperative complications. CONCLUSION: Although vertebral osteomyelitis due to ASMs is extremely rare, the risk of infection increases in cases of a fistula to the skin. When investigating the etiology of treatment-resistant infections, especially of the skin, sacral osteomyelitis and an underlying anomaly must be kept in mind.

Schwannoma of the conus medullaris: a rare case.

Intradural schwannoma of the conus medullaris is a rare form of spinal neoplasm, which commonly occurs in the lumbar region. Conus medullaris level is unusual for schwannomas. A 49-year-old woman presented with chronic sciatica, mild bladder dysfunction, and paresthesia in the buttocks. Magnetic resonance imaging of the spine showed a mass lesion in the conus medullaris region with nerve compression. The tumor was completely resected and diagnosed histologically as schwannoma. The patient recovered after surgery. Clinical and radiologic features of this rare tumor are reviewed and are accompanied by literature findings.

The lumbar roots and pedicles: a morphometric analysis and anatomical features.

The objective of this study was to conduct a morphometric analysis of the lumbar nerve roots and surrounding structures. In this investigation, the lumbar roots were studied in 14 cadavers (70 lumbar vertebrae). Lumbar pedicle heights and widths were measured at every level of the lumbar vertebrae. The largest mean root diameter was 5.6 mm (L5 root) and the smallest 3.5 mm (L1 root). With regard to the root-dura exit angle, the widest was measured at L1 as 26.2+/-1.6 degrees and the narrowest at L5 as 16.3+/-2.4 degrees. The widest lumbar pedicle was measured at L5 as 17.1+/-4.2 mm and the narrowest at L1 as 8.4+/-1.8 mm. The longest lumbar pedicle was measured at L2 as 15.3+/-2.2 mm and the shortest at L4 as 13.8+/-2.3 mm. Quantitative measurements of lumbar root diameters, their exit angles from the dura, and lumbar pedicle heights and widths in anatomical dissection models may help us to gain a deeper understanding of the pathologies of this region and positively influence the success of surgical interventions.

Effect of iloprost on adrenal medullary grafts in central nervous system transplantation and apoptosis.

OBJECTIVE: To investigate whether iloprost, a stable analog of prostacyclin, is useful for the preservation of neural grafts in transplantation surgery. METHODS: This study was conducted at the Microsurgery Laboratory of the Department of Neurosurgery, Faculty of Medicine, Ankara University, Ankara, Turkey in 2003. The animals (rabbits) were divided into 3 groups. In group I, autografts taken from the adrenal medulla were stored in 0.9% sodium chloride (NaCl) solution for 45 minutes before transplantation. In group II, autografts taken from the adrenal medulla were stored in iloprost solution (50 ng/ml) for 45 minutes before transplantation. Graft transplantation was not performed in the third group. RESULTS: In group I, the grafts partially preserved their viability. In group II, the large adrenal medullary cells had evident euchromatin nuclei fused with neurons, and there was an increase in vascularization. CONCLUSION: Three weeks after transplantation surgery, it was determined that iloprost maintained the viability of the graft tissue and probably prevented apoptosis, and facilitated the integration of the graft tissue into the host brain.

Neuronavigation-assisted transoral-transpharyngeal approach for basilar invagination--two case reports.

Two patients presented with congenital basilar invagination manifesting as progressive myelopathy. Both patients underwent surgery using a neuronavigation-assisted transoral-transpharyngeal approach. The Brain-LAB Vector Vision navigation system was used for image guidance. The registration accuracies were 0.9 and 1.3 mm. After decompression, posterior stabilization was performed. Both patients had an uneventful postoperative course. The transoral-transpharyngeal approach with the neuronavigation system provides safe exposure and decompression for basilar invagination.

Spinal intradural-intramedullary cavernous malformation. Case report and literature review.

Cavernous angiomas or cavernomas are uncommon vascular malformations of the central nervous system and spinal involvement is much rarer especially in pediatric patients. We report a case of spinal intradural-intramedullary cavernous angioma in a 14-year-old male child. The cavernoma was located at the level of C6-C7 at the dorsal part of the spinal cord. The diagnosis was made with MRI and the patient underwent surgical treatment. The cavernoma was totally removed with laminotomy and microsurgical techniques. Somatosensory evoked potential monitoring was also used peroperatively. The clinical, radiological and surgical features of this rare case were presented and discussed with reference to the literature.

Bilateral traumatic neuroma of the anterior cervical nerve root: case report.

STUDY DESIGN: Case report. OBJECTIVES: A rare case of anterior cervical second root traumatic neuroma with no history of trauma is reported, and possible etiology is discussed. SUMMARY OF BACKGROUND DATA: Traumatic neuroma is the reactive, nonneoplastic proliferation in the injured nerve. Several atypical locations of traumatic neuroma have been reported. To date, only 4 cervical traumatic neuroma cases with no history of trauma have been reported, and, to our knowledge, there is no case of bilateral cervical traumatic neuroma published in the literature. METHODS: A patient with a history of neck and left upper extremity pain, who had hypoesthesia in left C2 dermatome on neurologic examination is presented. A left C2-C3 hemilaminectomy and tumor extirpation were performed. RESULTS: A histopathologic study revealed features of a typical traumatic neuroma. The patient had no deficits on her postoperative neurologic examination, and her neck and left arm pain improved. The unusual location of this lesion and possible etiology of such a traumatic neuroma are discussed. CONCLUSIONS: A rare case of anterior bilateral cervical second root traumatic neuroma with no history of trauma is reported. An unnoticed history of trauma may play an etiologic role in the development of these lesions.

Suprasellar germ cell tumor with subarachnoid seeding MRI and MR spectroscopy findings.

A case of suprasellar germinoma with subarachnoid seeding is presented. Patient had a history of depression unresponsive to drug therapy and recently developed diabetes insipidus. MR imaging revealed a huge suprasellar mass, heterogenous in signal intensity due to cystic components. MR spectroscopy of the mass showed prominent lipid peak suggesting high malignant potential.

Extraforaminal lumbar arterial anatomy.

BACKGROUND: There are few studies carried out to reveal lumbar arterial anatomy. The studies of vascular anatomy of the lumbar zone are usually based on the angiographic imaging methods and barium injected radiographic sections of human specimens. METHODS: Upon the recent breakthroughs in the microscopic anatomic dissections, the vascular structure of this zone is examined in 16 cadavers. Arterial anatomies of the extraforaminal zones of 80 lumbar vertebral objects were studied. RESULTS: In each segment, lumbar artery, extraforaminal branches of the lumbar artery and the spinal (foraminal) branch were described. The spinal branch is originated from lumbar artery and extends as the dorsal branch. The dorsal branch is divided into 4 branches: ganglionic, transverse, ascending, and descending. Diameters of the lumbar artery, spinal, dorsal, and ganglionic branches were measured at each stage. The mean diameter of the lumbar artery was 2.7 mm, the dorsal branch was 2.0 mm, the foraminal branch was 1.9 mm, and the ganglionic branch was 1.0 mm, respectively. CONCLUSION: Knowledge of lumbar arterial anatomy is needed for carrying out a successful surgical operation and reducing complications.