Microsurgical anatomy and approaches to thalamic gliomas. Part 2: Maximal safe resection of thalamic gliomas improves outcomes. A single-center experience.

OBJECTIVE: As presented in Part 1 of this series, thalamic gliomas (TGs) are deep-seated, difficult-to-access tumors surrounded by vital neurovascular structures. Given their high operative morbidity, TGs have historically been considered inoperable lesions. Although maximal safe resection (MSR) has become the treatment standard for lobar and even deep-seated mediobasal temporal and insular gliomas, the eloquent location of TGs has precluded this management strategy, with biopsy and adjuvant treatment being the mainstay. The authors hypothesized that MSR can be achieved with low morbidity and mortality for TGs, thus resulting in improved outcomes. METHODS: A retrospective single-center study was performed on all TG patients from 2006 to 2020. Clinical, imaging, and pathology reports were obtained. Univariate and multivariate analyses were performed to determine prognostic variables. Case examples illustrate various approaches and the rationale for staging resections of more complex TGs. RESULTS: A total of 42 patients (26 males, 16 females), among them 12 pediatric (29%) cases, were included. Their mean age was 36.0 ± 21.4 (median 30, range 3-73) years. The median maximal tumor diameter was 45 (range 19-70) mm. Eighteen patients (43%) had a prior stereotactic needle tumor biopsy, with the ultimate diagnosis changed for 7 patients (39%) following microsurgical resection. The most common surgical approaches were transtemporal (29%), anterior interhemispheric transcallosal (29%), and superior parietal lobule (25%). Overall, the combined subtotal and gross-total resection rate was 95% (n = 40). Low-grade gliomas (LGGs; grades I and II) comprised one-third of the group, whereas half of the patients had glioblastoma multiforme. There were no operative mortalities. Although temporary postoperative motor deficits were observed in 12 patients (28.6%), all improved during the early postoperative period except 1 (2.4%), who had mild residual hemiparesis. Two patients required CSF diversion for hydrocephalus. The 2-year overall survival rate was 90% for LGG patients and 15% for high-grade glioma (HGG) patients. Multivariate analysis revealed that histological grade, age, and extent of resection were independent prognostic factors associated with survival. CONCLUSIONS: Management of TGs is challenging, with resection avoided by many, if not most, neurosurgeons, especially for HGGs. The results reported here demonstrate improved outcomes with resection, particularly in younger LGG patients. The authors therefore advocate for MSR for a select cohort of TG patients using carefully planned surgical approaches, contemporary intraoperative adjuncts, and meticulous microsurgical techniques.

Clinical Significance of Pneumocephalus in Pediatric Mild Traumatic Brain Injury.

OBJECTIVES: Mild traumatic brain injury (mTBI) comprises most (70%-90%) of all pediatric head trauma cases seeking emergency care. Although most mTBI cases have normal initial head computed tomography scan, a considerable portion of the cases have intracranial imaging abnormalities on computed tomography scan. Whereas other intracranial pathological findings have been extensively studied, little is known about the clinical significance of pneumocephalus in pediatric mTBI. METHODS: We retrospectively identified pediatric mTBI patients with pneumocephalus using the institutional database of a large regional trauma referral center. Outcome measures were defined as clinically important TBI (ciTBI), hospitalization, intensive care unit (ICU) admission, and neurosurgical intervention. Comparisons were made between pneumocephalus and control (isolated linear fracture) groups as well as between isolated (only linear fracture and pneumocephalus) and nonisolated pneumocephalus (pneumocephalus and TBI) groups. RESULTS: Among 3524 pediatric mTBI cases, 43 cases had pneumocephalus (1.2%). Twenty-one cases (48.8%) had isolated pneumocephalus. The pneumocephalus group had higher rates of ciTBI, hospital admission, ICU admission, and neurosurgery when compared with the isolated linear fracture (control) group. The isolated pneumocephalus group had fewer ciTBI (21.1% vs 70%, P = 0.002), fewer hospitalization (23.8% vs 81.8%, P < 0.001), but similar ICU admission rates (4.8% vs 22.7%, P = 0.089) and length of hospital stay (4.0 ± 2.7 vs 3.6 ± 2.4 days, P = 0.798) in comparison to the nonisolated pneumocephalus group. None of the patients in the isolated group had neurosurgery whereas 2 patients in the nonisolated pneumocephalus group underwent surgery. Multivariable analysis revealed pneumocephalus as an independent predictor of ciTBI and hospital admission, but not ICU admission or neurosurgical intervention. CONCLUSION: Pneumocephalus is associated with increased rates of hospitalization and ciTBI, but not ICU admission, unfavorable outcome, or neurosurgical intervention in pediatric mTBI. Although usually spontaneously resolving pathology, it may occasionally be linked with complications such as cerebrospinal fluid leakage, meningitis, and tension pneumocephalus. Therefore, careful evaluation, close observation, and early detection of complications may prevent adverse outcomes.

Use of 3-Dimensional Modeling and Augmented/Virtual Reality Applications in Microsurgical Neuroanatomy Training.

BACKGROUND: Understanding the microsurgical neuroanatomy of the brain is challenging yet crucial for safe and effective surgery. Training on human cadavers provides an opportunity to practice approaches and learn about the brain's complex organization from a surgical view. Innovations in visual technology, such as virtual reality (VR) and augmented reality (AR), have immensely added a new dimension to neuroanatomy education. In this regard, a 3-dimensional (3D) model and AR/VR application may facilitate the understanding of the microsurgical neuroanatomy of the brain and improve spatial recognition during neurosurgical procedures by generating a better comprehension of interrelated neuroanatomic structures. OBJECTIVE: To investigate the results of 3D volumetric modeling and AR/VR applications in showing the brain's complex organization during fiber dissection. METHODS: Fiber dissection was applied to the specimen, and the 3D model was created with a new photogrammetry method. After photogrammetry, the 3D model was edited using 3D editing programs and viewed in AR. The 3D model was also viewed in VR using a head-mounted display device. RESULTS: The 3D model was viewed in internet-based sites and AR/VR platforms with high resolution. The fibers could be panned, rotated, and moved freely on different planes and viewed from different angles on AR and VR platforms. CONCLUSION: This study demonstrated that fiber dissections can be transformed and viewed digitally on AR/VR platforms. These models can be considered a powerful teaching tool for improving the surgical spatial recognition of interrelated neuroanatomic structures. Neurosurgeons worldwide can easily avail of these models on digital platforms.

Important Finding for COVID-19 Pandemic: Hydrocephalus-producing effect of Vaporized Alcohol Disinfectant.

BACKGROUND: Alcohol exposure may cause hydrocephalus, but the effect of vaporized nasal alcohol exposure on the choroid plexus, and ependymal cells, and the relationship between alcohol exposure and developing hydrocephalus are not well known. This subject was investigated. METHODS: Twenty-four male (∼380 g) Wistar rats were used in this study. The animals were divided into three groups, as the control, sham and study groups. The study group was further divided into two groups as the group exposed to low or high dose of alcohol. The choroid plexuses and intraventricular ependymal cells and ventricle volumes were assessed and compared statistically. RESULTS: Degenerated epithelial cell density of 22 ± 5, 56 ± 11, 175 ± 37, and 356 ± 85/mm3 was found in the control, sham, low alcohol exposure, and high alcohol exposure groups, respectively. The Evans index was <34% in the control group, >36% in the sham group, >40% in the group exposed to low alcohol dose (low-dose alcohol group), and >50% in the group exposed to high dose of alcohol (high-dose alcohol group). CONCLUSIONS: It was found that alcohol exposure caused choroid plexus and ependymal cell degeneration with ciliopathy and enlarged lateral ventricles or hydrocephalus. In the COVID-19 pandemic era, our findings are functionally important, because alcohol has often been used for hygiene and prevention of transmission of the Sars-Cov-2-virus.

Development and Validation of a Novel Methodological Pipeline to Integrate Neuroimaging and Photogrammetry for Immersive 3D Cadaveric Neurosurgical Simulation.

Background: Visualizing and comprehending 3-dimensional (3D) neuroanatomy is challenging. Cadaver dissection is limited by low availability, high cost, and the need for specialized facilities. New technologies, including 3D rendering of neuroimaging, 3D pictures, and 3D videos, are filling this gap and facilitating learning, but they also have limitations. This proof-of-concept study explored the feasibility of combining the spatial accuracy of 3D reconstructed neuroimaging data with realistic texture and fine anatomical details from 3D photogrammetry to create high-fidelity cadaveric neurosurgical simulations. Methods: Four fixed and injected cadaver heads underwent neuroimaging. To create 3D virtual models, surfaces were rendered using magnetic resonance imaging (MRI) and computed tomography (CT) scans, and segmented anatomical structures were created. A stepwise pterional craniotomy procedure was performed with synchronous neuronavigation and photogrammetry data collection. All points acquired in 3D navigational space were imported and registered in a 3D virtual model space. A novel machine learning-assisted monocular-depth estimation tool was used to create 3D reconstructions of 2-dimensional (2D) photographs. Depth maps were converted into 3D mesh geometry, which was merged with the 3D virtual model's brain surface anatomy to test its accuracy. Quantitative measurements were used to validate the spatial accuracy of 3D reconstructions of different techniques. Results: Successful multilayered 3D virtual models were created using volumetric neuroimaging data. The monocular-depth estimation technique created qualitatively accurate 3D representations of photographs. When 2 models were merged, 63% of surface maps were perfectly matched (mean [SD] deviation 0.7 ± 1.9 mm; range -7 to 7 mm). Maximal distortions were observed at the epicenter and toward the edges of the imaged surfaces. Virtual 3D models provided accurate virtual measurements (margin of error <1.5 mm) as validated by cross-measurements performed in a real-world setting. Conclusion: The novel technique of co-registering neuroimaging and photogrammetry-based 3D models can (1) substantially supplement anatomical knowledge by adding detail and texture to 3D virtual models, (2) meaningfully improve the spatial accuracy of 3D photogrammetry, (3) allow for accurate quantitative measurements without the need for actual dissection, (4) digitalize the complete surface anatomy of a cadaver, and (5) be used in realistic surgical simulations to improve neurosurgical education.

A Novel Decision-Support Tool (IniCT Score) for Repeat Head Computed Tomography in Pediatric Mild Traumatic Brain Injury.

BACKGROUND: The necessity of computed tomography (CT) has been questioned in pediatric mild traumatic brain injury (mTBI) because of concerns related to radiation exposure. Distinguishing patients with lower and higher risk of clinically important TBI (ciTBI) is paramount to the optimal management of these patients. OBJECTIVE: This study aimed to analyze the imaging predictors of ciTBI and develop an algorithm to identify patients at low and high risk for ciTBI to inform clinical decision making using a large single-center cohort of pediatric patients with mTBI. METHODS: We retrospectively identified pediatric patients with mTBI with repeat CT within 48 hours of injury using an institutional database. RESULTS: Among 3867 pediatric patients, 219 patients with mTBI with repeat CT were included. Thirty-eight had ciTBI (17%), 16 (7%) required intensive care unit admission, and 6 (3%) underwent surgery. Median time interval between initial and repeat CT was 7 hours (range, 4-10). Clinical worsening and radiologic progression were evident in 36 (16%) and 24 (11%) patients, respectively. Multivariate analysis showed that 5 pathologic findings (depressed skull fracture, pneumocephalus, epidural hematoma, subdural hematoma, and contusion) on initial CT and radiologic progression on repeat CT were independent predictors of ciTBI. A new scoring system based on these 5 factors on initial CT (IniCT [Initial CT scoring system] score) had excellent discrimination for ciTBI, need for intensive care unit admission, and neurosurgery (area under the curve >0.8). CONCLUSIONS: The IniCT scoring system can successfully differentiate low-risk and high-risk patients based on initial CT scan. Zero score can eliminate the need for a routine repeat CT, whereas scores ≥2 should prompt serial neurologic examinations and/or repeat CT depending on the clinical situation.

Contralateral vs. Ipsilateral Approach to Superior Hypophyseal Artery Aneurysms: An Anatomical Study and Morphometric Analysis.

Introduction: Surgical clipping of superior hypophyseal artery (SHA) aneurysms is a challenging task for neurosurgeons due to their close anatomical relationships. The development of endovascular techniques and the difficulty in surgery have led to a decrease in the number of surgical procedures and thus the experience of neurosurgeons in this region. In this study, we aimed to reveal the microsurgical anatomy of the ipsilateral and contralateral approaches to SHA aneurysms and define their limitations via morphometric analyses of radiological anatomy, three-dimensional (3D) modeling, and surgical illustrations. Method: Five fixed and injected cadaver heads underwent dissections. In order to make morphometric measurements, 75 cranial MRI scans were reviewed. Cranial scans were rendered with a module and used to produce 3D models of different anatomical structures. In addition, a medical illustration was drawn that shows different sizes of aneurysms and surgical clipping approaches. Results: For the contralateral approach, pterional craniotomy and sylvian dissection were performed. The contralateral SHA was reached from the prechiasmatic area. The dissected SHA was approached with an aneurysm clip, and maneuverability was evaluated. For the ipsilateral approach, pterional craniotomy and sylvian dissection were performed. The ipsilateral SHA was reached by mobilizing the left optic nerve with left optic nerve unroofing and left anterior clinoidectomy. MRI measurements showed that the area of the prechiasm was 90.4 ± 36.6 mm2 (prefixed: 46.9 ± 10.4 mm2, normofixed: 84.8 ± 15.7 mm2, postfixed: 137.2 ± 19.5 mm2, p < 0.001), the distance between the anterior aspect of the optic chiasm and the limbus sphenoidale was 10.0 ± 3.5 mm (prefixed: 5.7 ± 0.8 mm, normofixed: 9.6 ± 1.6 mm, postfixed:14.4 ± 1.6 mm, p < 0.001), and optic nerves' interneural angle was 65.2° ± 10.0° (prefixed: 77.1° ± 7.3, normofixed: 63.6° ± 7.7°, postfixed: 57.7° ± 5.7°, p: 0.010). Conclusion: Anatomic dissections along with 3D virtual model simulations and illustrations demonstrated that the contralateral approach would potentially allow for proximal control and neck control/clipping in smaller SHA aneurysm with relatively minimal retraction of the contralateral optic nerve in the setting of pre- or normofixed chiasm, and ipsilateral approach requires anterior clinodectomy and optic unroofing with considerable optic nerve mobilization to control proximal ICA and clip the aneurysm neck effectively.

The role of microsurgery for poor-grade aneurysmal subarachnoid hemorrhages in the endovascular era.

BACKGROUND: Poor-grade aneurysmal subarachnoid hemorrhage (PGASAH) is associated with high mortality and morbidity regardless of treatment. Herein, we re-evaluate the safety and efficacy of microsurgical treatment for managing PGASAH patients in the current endovascular era. METHODS: We retrospectively reviewed 141 consecutive patient records in a single institution who underwent microsurgical (n = 80) or endovascular (n = 61) treatment for PGASAH. RESULTS: Baseline characteristics were similar, except for more intracerebral hematomas (46.3% vs 24.6%, p = 0.009), fewer intraventricular hemorrhages (26.3% vs 59%, p < 0.001), and fewer posterior circulation aneurysms (5.1% vs 44.3%, p < 0.001) in the microsurgery group. Decompressive craniectomy (58.5% vs 24.6%, p < 0.001) and shunt-dependent hydrocephalus (63.7% vs 41%, p = 0.01) were more common for microsurgery, while procedural ischemic complications were less common (5% vs 24.6%, p = 0.001). Both early (12.5% vs 32.8%, p = 0.006) and late mortality rates (22.5% vs 39.3%, p = 0.041) were lower for microsurgery, and favorable 12-month outcomes (modified Rankin scale = 0-2) were better (62.5% vs 42.6%, p = 0.026). Multivariate analysis revealed that advanced age, neurological grade, modified Fisher grade, larger aneurysm size, rebleeding, and cerebral infarctions were independent predictors of poor outcome. Microsurgery fared marginally better than endovascular treatment (OR: 2.630, 95% CI: [0.991-6.981], p = 0.052). CONCLUSIONS: Timely and efficient treatment, either via open microsurgery or endovascular surgery, provided favorable outcomes for over half of PGASAH patients in this series. Therefore, early treatment should be offered to all PGASAH patients regardless of clinical and/or radiological factors. Microsurgery remains an effective treatment modality for selected PGASAH patients in the endovascular era.

Lumbar Intradiscal Ozone Chemonucleolysis Applied Together with the Epidural Steroid Treatment.

OBJECTIVES: Intradiscal ozone treatment is a minimally-invasive method that can be applied to patients who have low back pain and do not respond to conservative treatment. This retrospectively designed study aimed to evaluate its clinical efficacy, adverse effects, or complication rates. METHODS: Patients with lumbar degenerative disc disease (LDDD) who underwent intradiscal O2-O3 treatment between January 2016 and April 2018 were included in the study. Pain and disability levels were assessed at pre-injection, 1-month and 1-year post-injection periods using visual analog scale (VAS) and Oswestry Disability Index (ODI), respectively. RESULTS: A total of 520 patients (270 males and 250 females) with the mean age of 38.9±5.7 years included in the study. First-month and 1st-year post-injection VAS and ODI scores were significantly lower than pre-injection scores (p<0.001). Remarkable VAS score reduction (more than 50%) was found in 60.2% of patients at 1st month and in 52.9% of patients at the 1st year. No important side effects recorded. CONCLUSION: Intradiscal ozone therapy applied together with the epidural steroid treatment, one of the percutaneous application techniques for the treatment of low back pain related to LDDD, has successful outcomes, clinical efficacy, and low rate of side effects, and thus, is one of the methods that should be considered before surgery when appropriate patients.

Influence of Human Telomerase Reverse Transcriptase Mutation on the Aggressiveness and Recurrence in Meningiomas.

BACKGROUND:  Over 200 human telomerase reverse transcriptase (hTERT) polymorphism combinations have been implicated in the development of cancer. This study aimed to evaluate hTERT mutations in meningioma tissue and its association with meningioma. MATERIAL AND METHODS: A total of 90 patients who underwent surgery between 2006 and 2015 and were histopathologically diagnosed with meningioma (WHO 2016) were included. RESULTS: Among the 90 participants included herein, 50 (55.5%) and 40 (44.5%) were female and male, respectively, with an average age of 56.2 ± 14 years. Mean Ki-67 values were 10.56% (SD 12.41, range 0-60), while the mean follow-up duration was 39.1 months (SD 26.3). Low- and high-grade patients had a mean Ki-67 score of 4.31% (SD 3.58, range 0-16) and 19.92% (SD 14.91, range 2-60) (p = 0.0001). Our results showed a moderate positive correlation between Ki-67 score and the presence of hTERT mutation (Pearson correlation test, r = 0.5161; p = 0.0001). Patients with an hTERT mutation > 30% had significantly higher risk for reoperation than those with lower levels of mutation (p = 0.016, chi square test). None of the patients requiring reoperation had an hTERT mutation < 10%. Moreover, high-grade patients had a 7.2 times higher risk of reoperation than those with an hTERT mutation > 30%. CONCLUSION: The presence of hTERT mutation, in addition to high Ki-67, indicated a more aggressive meningioma disease course and potentially increased risk of recurrence.

Surgical Strategies for Cerebral Revascularization in Patients with Limited Bypass Conduit Options and Unexpected Intraoperative Difficulties.

BACKGROUND: Cerebral bypass procedures are complex and require substantial experience and skills and thorough preoperative planning. Cerebrovascular surgeons face increasingly complex bypass cases because most routine cases are managed by endovascular means, and because increasing numbers of patients have complex medical problems that affect available and suitable bypass conduit options. We report the cases of several patients undergoing cerebral bypass with limited bypass conduit alternatives, in whom there were unexpected intraoperative difficulties requiring complex solutions. METHODS: The neurological surgery department database was reviewed to identify patients who had undergone cerebral bypass procedures during a 13-year period in whom there were limited available bypass conduits, and in whom unexpected intraoperative difficulties were encountered during cerebral bypass. RESULTS: Patient outcomes and graft patency were evaluated for 13 patients including 6 with ischemia, 3 with giant aneurysms, 2 with mycotic aneurysms, 1 with dissecting aneurysm, and 1 with gunshot-induced pseudoaneurysm. Median duration of follow-up was 43 months. In 12 of 13 patients, bypass graft/grafts were patent on the last computed tomography angiogram. In 1 patient, a prophylactic bypass procedure, the graft was not filling, probably because of lack of demand. Two patients died during follow-up of unrelated causes. CONCLUSIONS: Cerebrovascular surgeons should be versatile in dealing with patients with complex bypass. When there are limited available conduit options, we find that collaboration with other surgical specialties (e.g., plastics and vascular) is helpful. In patients in whom extreme intraoperative difficulties are expected, thorough preoperative planning with multiple backup plans should be exercised, as described in this report.

Effect of perioperative aspirin use on hemorrhagic complications in elective craniotomy for brain tumors: results of a single-center, retrospective cohort study.

OBJECTIVE: In daily practice, neurosurgeons face increasing numbers of patients using aspirin (acetylsalicylic acid, ASA). While many of these patients discontinue ASA 7-10 days prior to elective intracranial surgery, there are limited data to support whether or not perioperative ASA use heightens the risk of hemorrhagic complications. In this study the authors retrospectively evaluated the safety of perioperative ASA use in patients undergoing craniotomy for brain tumors in the largest elective cranial surgery cohort reported to date. METHODS: The authors retrospectively analyzed the medical records of 1291 patients who underwent elective intracranial tumor surgery by a single surgeon from 2007 to 2017. The patients were divided into three groups based on their perioperative ASA status: 1) group 1, no ASA; 2) group 2, stopped ASA (low cardiovascular risk); and 3) group 3, continued ASA (high cardiovascular risk). Data collected included demographic information, perioperative ASA status, tumor characteristics, extent of resection (EOR), operative blood loss, any hemorrhagic and thromboembolic complications, and any other complications. RESULTS: A total of 1291 patients underwent 1346 operations. The no-ASA group included 1068 patients (1112 operations), the stopped-ASA group had 104 patients (108 operations), and the continued-ASA group had 119 patients (126 operations). The no-ASA patients were significantly younger (mean age 53.3 years) than those in the stopped- and continued-ASA groups (mean 64.8 and 64.0 years, respectively; p < 0.001). Sex distribution was similar across all groups (p = 0.272). Tumor locations and pathologies were also similar across the groups, except for deep tumors and schwannomas that were relatively less frequent in the continued-ASA group. There were no differences in the EOR between groups. Operative blood loss was not significantly different between the stopped- (186 ml) and continued- (220 ml) ASA groups (p = 0.183). Most importantly, neither hemorrhagic (0.6%, 0.9%, and 0.8%, respectively; p = 0.921) nor thromboembolic (1.3%, 1.9%, and 0.8%; p = 0.779) complication rates were significantly different between the groups, respectively. In addition, the multivariate model revealed no statistically significant predictor of hemorrhagic complications, whereas male sex (odds ratio [OR] 5.9, 95% confidence interval [CI] 1.7-20.5, p = 0.005) and deep-extraaxial-benign ("skull base") tumors (OR 3.6, 95% CI 1.3-9.7, p = 0.011) were found to be independent predictors of thromboembolic complications. CONCLUSIONS: In this cohort, perioperative ASA use was not associated with the increased rate of hemorrhagic complications following intracranial tumor surgery. In patients at high cardiovascular risk, ASA can safely be continued during elective brain tumor surgery to prevent potential life-threatening thromboembolic complications. Randomized clinical trials with larger sample sizes are warranted to achieve a greater statistical power.

A novel, low-cost, reusable, high-fidelity neurosurgical training simulator for cerebrovascular bypass surgery.

OBJECTIVECerebrovascular bypass surgery is a challenging yet important neurosurgical procedure that is performed to restore circulation in the treatment of carotid occlusive diseases, giant/complex aneurysms, and skull base tumors. It requires advanced microsurgical skills and dedicated training in microsurgical techniques. Most available training tools, however, either lack the realism of the actual bypass surgery (e.g., artificial vessel, chicken wing models) or require special facilities and regulations (e.g., cadaver, live animal, placenta models). The aim of the present study was to design a readily accessible, realistic, easy-to-build, reusable, and high-fidelity simulator to train neurosurgeons or trainees on vascular anastomosis techniques even in the operating room.METHODSThe authors used an anatomical skull and brain model, artificial vessels, and a water pump to simulate both extracranial and intracranial circulations. They demonstrated the step-by-step preparation of the bypass simulator using readily available and affordable equipment and consumables.RESULTSAll necessary steps of a superficial temporal artery-middle cerebral artery bypass surgery (from skin opening to skin closure) were performed on the simulator under a surgical microscope. The simulator was used by both experienced neurosurgeons and trainees. Feedback survey results from the participants of the microsurgery course suggested that the model is superior to existing microanastomosis training kits in simulating real surgery conditions (e.g., depth, blood flow, anatomical constraints) and holds promise for widespread use in neurosurgical training.CONCLUSIONSWith no requirement for specialized laboratory facilities and regulations, this novel, low-cost, reusable, high-fidelity simulator can be readily constructed and used for neurosurgical training with various scenarios and modifications.

Chronic subdural hematoma associated with arachnoid cyst of the middle fossa : Surgical treatment and mid-term results in fifteen patients.

AIM: We report the neurological and radiological features, surgical management and Mid-term outcome in a series of patients with chronic subdural hematoma (CSDH) and associated ipsilateral arachnoid cyst (AC) of the middle fossa. MATERIAL AND METHODS: Between August 2004 and August 2012, 453 patients were treated with diagnosis of CSDH in our clinic. Of those, 15 patients had ipsilateral arachnoid cyst in the middle fossa. A single burr hole craniostomy was performed to drain the hematoma and the AC left intact at first in 14 patients, one patient had no surgical intervention. Follow-up period ranged from 13 months to 88 months (mean 43.07 ± 23.23 months). RESULTS: The patients having CSDH with AC were found to be younger than the patients with CSDH alone, the mean age was 13.93 ±12.37 years Eleven patients had head trauma 21 to 50 days before admission. Hematoma evacuation through a single burr hole and closed system subdural drainage 2 to 4 days after surgery improved the symptoms in all patients. Two patients developed subdural fluid collection which is treated by subduroperitoneal shunt placement. CONCLUSION: Greater prevalence of ACs in patients with CSDHs has been reported in the literature. We recommend the drainage of the hematoma via a single craniostomy and to leave the AC intact as the first choice of treatment if the associated AC is a Galassi type I or II. Additional subduroperitoneal shunting may be performed in patients with Galassi type III cyst.