Management of Persistent Syringomyelia in Patients Operated for Chiari Malformation Type 1.

BACKGROUND: The treatment of persistent syringomyelia associated with Chiari malformation type 1 (CM1) is unclear. This study aims to evaluate the clinical and radiologic outcomes of syringo-subarachnoid shunt (SSS) as a treatment for persistent syringomyelia following posterior fossa decompression (PFD) for CM1. METHODS: Forty-nine cases treated for CM1 associated syringomyelia at a single center were analyzed, 17 of them undergoing reoperation due to persistent syrinx formation. The patients' demographic data, neurologic presentations, and radiologic results were analyzed, including cerebellar herniation, posterior fossa volume, the level at which the syrinx started and finished, the size and diameter of the syrinx. RESULTS: Seventeen patients underwent SSS placement, with 1 minor surgical complication (a cerebrospinal fluid leak) occurring and requiring revision. No morbidity or mortality was observed. Among these 17 reoperated patients, partial or complete resorption of the syrinx was observed in all cases. The results suggest that if the syrinx diameter is >10 mm at its thickest point, extends for more than 10 vertebrae, and starts from the upper cervical region and extends to the upper thoracic region, the syrinx may not regress after the first surgery and potentially predicting the need for a second operation before PFD. CONCLUSIONS: SSS placement for persistent syrinx following PFD for CM1 is a safe and effective surgical treatment method. These criteria may also help predict the need for a second surgery and the overall disease outcome for both the surgeon and patient.

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.

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.

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.

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.

New experimental finding of dangerous autonomic ganglia changes in cardiac injury following subarachnoid hemorrhage; a reciprocal culprit-victim relationship between the brain and heart.

OBJECTIVE: The vagal, stellate, and cardiac ganglia cells changes following subarachnoid hemorrhage (SAH) may occur. This study aimed to investigate if there is any relation between vagal network/stellate ganglion and intrinsic cardiac ganglia insult following SAH. MATERIALS AND METHODS: Twenty-six rabbits were used in this study. Animals were randomly divided as control (GI, n = 5); SHAM 0.75 cc of saline-injected (n = 5) and study with autologous 1.5 cc blood injection into their cisterna magna(GIII, n = 15). All animals were followed for three weeks and then decapitated. Their motor vagal nucleus, nodose, stellate, and intracardiac ganglion cells were estimated by stereological methods and compared statistically. RESULTS: Numerical documents of heart-respiratory rates, vagal nerve- ICG, and stellate neuron densities as follows: 276 ± 32/min-22 ± 3/min-10.643 ± 1.129/mm3-4 ± 1/mm3-12 ± 3/mm3 and 2 ± 1/cm3 in the control group; 221 ± 22/min-16 ± 4/min-8.699 ± 976/mm3-24 ± 9/mm3-103 ± 32/mm3 and 11 ± 3/cm3 in the SHAM group; and 191 ± 23/min-17 ± 4/min-9.719 ± 932/mm3-124 ± 31/mm3-1.542 ± 162/mm3 and 32 ± 9/cm3 in the SAH (study) group. The animals with burned neuro-cardiac web had more neurons of stellate ganglia and a less normal neuron density of nodose ganglia (p < 0.005). CONCLUSION: Sypathico-parasympathetic imbalance induced vagal nerve-ICG disruption following SAH could be named as Burned Neurocardiac Web syndrome in contrast to broken heart because ICG/parasympathetic network degeneration could not be detected in classic broken heart syndrome. It was noted that cardiac ganglion degeneration is more prominent in animals' severe degenerated neuron density of nodose ganglia. We concluded that the cardiac ganglia network knitted with vagal-sympathetic-somatosensitive fibers has an important in heart function following SAH. The neurodegeneration of the cardiac may occur in SAH, and cause sudden death.

Protective Felix Culpa Effect of Superior Sympathetic Cervical Ganglion Degenerations on Prevention of Basilar Artery Spasm After Subarachnoid Hemorrhage: A Preliminary Experimental Study.

BACKGROUND: Posterior cerebral blood flow is regulated by the basilar arteries (BAs). Vasospasm of BAs can occur after subarachnoid hemorrhage (SAH). Superior cervical sympathetic ganglia (SCG) fibers have a vasoconstrictor effect on the BA. We aimed to investigate the relationship between the degenerated neuron density of the SCG and the severity of BA vasospasm after experimental SAH. METHODS: Twenty-four rabbits were used. Five were used as the control group, and 5 were used as the sham group. Experimental SAHs were performed in the remaining 14 animals (study group) by injecting homologous blood into the cisterna magna. After 3 weeks of injection, neuron densities of SCG and the severity of BA vasospasm index values (VSI) were examined histopathologically and compared statistically. RESULTS: The mean VSI was 0.669 ± 0.1129 in the control group, 0.981 ± 0.159 in the sham group, and 1.512 ± 0.298 in the study group. The mean degenerated neuronal density of SCG was 436 ± 79/mm3 in severe vasospasm (n = 3), 841 ± 101/mm3 in moderate vasospasm (n = 4), and 1.921 ± 849/mm3 in the less vasospasm detected animals (n = 6). CONCLUSIONS: This study shows an inverse relationship between the degenerated neuronal density in the SCG and VSI values. This finding indicates a diminished sympathetic input from the SCG, resulting in a beneficial effect (the felix culpa) by dilating the lumen diameter of the BA, so SCG degeneration after SAH protects the BA spasm.

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.

Modic changes and its association with other MRI phenotypes in east Anatolian low back pain patients.

OBJECTIVE: Modic changes (MCs) are known to be associated with low back pain (LBP). Literature contains conflicting reports about the prevalence of MCs and other spinal phenotypes among different populations with LBP patients. We aimed to evaluate the prevalence of MCs in the lumbar spine and associated features in Eastern Anatolian chronic LBP patients. METHODS: The study sample comprised of 786 consecutive patients [(490 female, 296 male), (mean age 39.7; range 20-78)] with a history of low back pain for at least 3 months. Data about MCs involvement, Schmorl's nodes (SN), disc degeneration (DD), disc displacement, disc height and osteophytes were obtained via MRI. Patients' demographic characteristics, Oswestry disability index (ODI) and visual analog scale (VAS) scores were assessed using a questionnaire. RESULTS: MCs were present in 67.2% (528/786) of the patients. Of all evaluated lumbar-level changes, 86 (6.2%) were Type I, 991 (76.8%) were Type II, 11 (0.8%) were Type III, 47 (6.5%) were Type II/III, 89 (8.5%) were Type I/II, and 29 (1.2%) were Type I/II/III MCs. MCs were significantly associated with severe DD (p < 0.001), disc displacement (p < 0.001), SN (p < 0.001), and osteophytes (p < 0.001). In the multivariate regression analysis, BMI (for both ODI and VAS) and age (only for ODI) were the only independent predictors of clinical severity. CONCLUSIONS: The present study is the largest cross-sectional study of adult members of the Eastern Anatolian population with chronic LBP. Modic changes were detected in 67.2% of patients with chronic LBP and the prevalence of other phenotypic features differed significantly between MCs and non-MCs disc levels. Nevertheless, the results of the current study do not support a causal relationship of MCs or any MRI changes with clinical symptom severity.

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.

The Continuing Impact of Coronavirus Disease 2019 on Neurosurgical Training at the 1-Year Mark: Results of a Nationwide Survey of Neurosurgery Residents in Turkey.

OBJECTIVE: The impact of the coronavirus disease 2019 (COVID-19) pandemic has led to a significant transformation in medical practice and training. This nationwide survey study aims to evaluate the 1-year impact of the pandemic on training of neurosurgical residents. METHODS: A 38-question Web-based survey was sent to 356 neurosurgery residents. Two hundred and thirty-five participated in the study (66% response rate), representing more than half of all neurosurgical residents in the country. RESULTS: Assignment to direct COVID-19 medical care was common (85.5%). Many of the neurosurgery residents (37.9%) were tested positive for COVID-19. Almost half of the respondents reported a decrease in work hours. Most participants (84.3%) reported a decline in total operative case volume (mean change, -29.1% ± 1.6%), largely as a result of a decrease in elective (-33.2% ± 1.6%) as opposed to emergency cases (-5.1% ± 1.8%). For theoretic education, most respondents (54.9%) indicated a negative impact, whereas 25.1% reported a positive impact. For practical training, most respondents (78.7%) reported an adverse effect. A decrease in elective surgical case volume predicted a positive impact on theoretic training but a negative impact on practical training. Research productivity was reported by 33.2% to have decreased and by 23% to have increased. Forty-two percent indicated an increase in concerns about their training and career, with a negative impact on practical training being the most important predictor. Most (57.4%) had considered extending residency training to overcome negative effects of the pandemic. CONCLUSIONS: COVID-19 has had a significant impact on neurosurgical practice and training. Effective measures should be used to mitigate these effects and better prepare for the future challenges.

Analysis and Differences of the Neurosurgical Complications During COVID-19 Pandemic.

Objectives: The objective of the study was to analyze the complications of neurosurgical operations during the COVID-19 pandemic by comparing them with the complications observed in the pre-pandemic period. Methods: Two groups were formed: (1) Patients who were operated in the 5-month period of the pandemic (March-July 2020) and (2) those who were operated the same operations in the same period 1 year before (March-July 2019). Demographics, characteristics, medical follow-up data, complications, and outcome compared between the groups. Results: Similar demographics were observed between the groups. The number of all neurosurgical cases and neurotrauma cases decreased by 79% and 68% in pandemic period, respectively. The rate of emergency surgeries was significantly higher in pandemic group (p<0.001). The operation time was significantly longer in pandemic group (p=0.014). Total complication rate was significantly higher in pandemic group (p=0.002). Specifically, the rate of pulmonary complications was significantly higher during pandemic period (p<0.001). The infection rate (p<0.001), antibiotic use (p<0.001), and intensive care unit stay (p=0.023) were significantly higher in pandemic group. Conclusion: During pandemic period complication rates increased and a higher risk than expected was encountered. Treatment should be performed by taking the precautions and informing the patients about additional risks.

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.

Academic performance after neurosurgery residency training in Turkey: a national survey.

OBJECTIVE: Neurosurgery training programs aim to train specialists. In addition, they are expected to equip the residents with necessary knowledge and skills for academic development. This study aims to gain insights into academic productivity after neurosurgeons graduated from residency training in Turkey. METHODS: An electronic survey was sent to all Turkish Neurosurgical Society members (n = 1662 neurosurgeons) between September and November 2019. The number of participants was 289 (17.4%). Participants were divided into subgroups based on three main factors: training institution type (university hospital [UH] vs training and research hospital [TRH]), training institution annual case volume (low [< 1000 or inadequate cranial/spinal case numbers] vs high [> 1000 and adequate cranial/spinal case numbers]), and training program accreditation status (accredited vs nonaccredited). RESULTS: The majority of the participants (64.7%) graduated from the UHs. Those trained at UHs (vs TRHs) and high- (vs low-) volume centers had their dissertations more frequently published in Science Citation Index/Science Citation Index-Expanded journals, gave more oral presentations after residency, had higher h-indices, had higher rates of reviewership for academic journals, and had greater participation in projects with grant support. In addition, graduates of accredited programs reported more PhD degrees than those of nonaccredited programs. CONCLUSIONS: Neurosurgeons trained in higher-case-volume, accredited programs, mostly in the UHs, performed better in terms of scientific activities and productivity in Turkey. Strong research emphasis and supportive measures should be instituted to increase academic performance during and after residency training.

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.

Morphometric Assesment of the External Anatomy of Fourth Ventricle and Dorsal Brainstem in Fresh Cadavers.

AIM: To investigate the external anatomy of the fourth ventricle and dorsal brainstem using morphometric data, which could be useful for preoperative surgical planning. MATERIAL AND METHODS: Between January 2017 and December 2017, 42 fresh adult cadavers were investigated for the measurements of the cadaver brainstems and fourth ventricle, and they were recorded by photography. Measurements were evaluated according to body mass indexes (BMIs) of the patients. We also investigate the visualization of facial colliculus and stria medullaris on brainstem. RESULTS: A total of 42 fresh cadavers with a mean age of 45.38 ± 16.41 years old were included in this research. We found no statistically significant difference between measurements and BMIs. Facial colliculus was visualized in 92.9% (n=39), but it could not visualized in 7.1% (n=3) of the subjects. When the right side of the stria medullaris was examined, one bundle was seen in 59.5% (n=25) of the subjects, two bundles were seen in 31% (n=13) of the subjects, and 3 bundles were seen in 9.5% (n=4) of the subjects. When the left side of the stria medullaris was examined, one bundle was seen in 57.1% (n=24) of the subjects, two bundles were seen in 33.3% (n=14) of the subjects, and three bundles were seen in 9.5% (n=4) of the subjects. CONCLUSION: Knowledge of the normal morphometry of the dorsal brainstem as it has been reported in this study will help one to assess distortions in any preoperative imaging studies and surgical planning.

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.