Bifrontal-Parietal Ratio: A Novel Risk Factor for Cerebrospinal Fluid Overdrainage after Ventriculoperitoneal Shunting.

Objective This study aimed to examine potential risk factors associated with cerebrospinal fluid overdrainage after ventriculoperitoneal (VP) shunting. Materials and Methods We retrospectively examined the medical records of hydrocephalus patients who underwent VP shunting at a single institution between January 2011 and December 2017 and had a minimum 3-year follow-up. Variables studied included age, gender, hydrocephalus etiology, symptoms, shunt valve, ventricular catheter entry point, and neurosurgical history, including history of external ventricular drainage. Radiographic variables included Evans index, bicaudate index, callosal angle, measurements of frontal lobe thickness, and bifrontal-parietal ratio. Results Among the 182 study patients, 11 experienced overdrainage. Age, gender, etiology, symptoms, and surgical history did not significantly differ between patients who experienced overdrainage and those who did not. Evans index, bicaudate index, and callosal angle did not significantly differ between the groups. Measurements of frontal lobe thickness and bifrontal--parietal ratio were significantly lower in the overdrainage group. Conclusion Bifrontal-parietal ratio may be useful to predict overdrainage after VP shunt surgery.

Independent Factors Associated with 30-Day In-Hospital Mortality from Acute Spontaneous Intracerebral Hemorrhage.

OBJECTIVE: This study aims to investigate independent factors associated with 30-day mortality in patients with acute spontaneous intracerebral hemorrhage (SICH) before treatment. METHODS: A retrospective analysis was performed on medical records of patients hospitalized with acute SICH between 2019 and 2021. Data included personal history, hospital stay duration, symptom onset, chief complaint, underlying diseases, medication, and alcohol/smoking habits. Physical examination records comprised baseline blood pressure, Glasgow Coma Scale assessment, and pupil reaction evaluation. Diagnostic imaging, specifically computed tomography brain scans, was examined for hemorrhage details. Multivariable logistic analysis was utilized for data analysis. RESULTS: Among 663 cases, 185 (27.9%) experienced mortality. Risk factors for mortality included chronic kidney disease, ischemic heart disease, loss of follow-up in hypertension clinic, and pontine hemorrhage. Conversely, motor response (m), reactive pupils, and basal cistern persistence significantly decreased the risk of mortality in multivariable analysis. Receiver operating characteristic analysis identified a m score of 5 as the cutoff for predicting survival. CONCLUSIONS: Chronic kidney disease, ischemic heart disease, loss of hypertension follow-up, m, reactive pupils, pontine hemorrhage, and basal cistern persistence were independent variables associated with the 30-day mortality rate in SICH patients before treatment initiation. A m, pupil reaction, and basal cistern persistence serve as predictive tools for assessing mortality in SICH before treatment.

Long-term clinical outcomes of stereotactic radiotherapy for bilateral vestibular schwannomas in neurofibromatosis type 2 patients.

PURPOSE: The evidence for treating patients with neurofibromatosis 2-related vestibular schwannoma (VS-NF2) using hypofractionated stereotactic radiation therapy (HSRT) is limited. This study aimed to investigate clinical outcomes in patients with VS-NF2 treated with Robotic HSRT. METHODS: We retrospectively analyzed 25 NF2 patients with 48 VSs who were treated using Robotic HSRT at Ramathibodi Hospital from January 2009 to January 2020. RESULTS: Median follow-up was 98 months (range, 24-155 months). Median tumor volume was 2.3 cm3 (range, 0.4-28.3 cm3). Median prescribed dose was 18 Gy (range, 18-25 Gy) in three fractions (range, 3-5). The 5- and 10-year local control rates were 87% and 80%, respectively. The 5- and 10-year hearing preservation rates were 59% and 35%, respectively. Three patients developed new symptoms associated with transient volume expansion after treatment: hydrocephalus in one, facial weakness in one, and ataxia in one. No patient developed worsening of trigeminal nerve function. No histologically confirmed of radiation induced malignancy was reported in the study. CONCLUSIONS: Robotic HSRT demonstrated excellent long-term tumor control with a low non-auditory complication rate in patients with VS-NF2. However, preservation of hearing remains a major concern.

Clinical Outcomes of Intracranial Nonvestibular Schwannomas Treated with LinacBased Stereotactic Radiosurgery and Radiotherapy.

BACKGROUND: Intracranial nonvestibular schwannomas arising from various cranial nerves excluding CN VIII are uncommon. Recently, stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (SRT) have been widely reported as effective treatment modalities for nonvestibular schwannomas. The purpose of this study was to study the long term clinical outcome for nonvestibular schwannomas treated with both XKnife and CyberKnife (CK) radiosurgery at one institution. MATERIALS AND METHODS: From 2004 to 2013, fiftytwo nonvestibular schwannoma patients were included in this study, 33 patients (63%) were treated with CK, and 19 (37%) were treated with XKnife. The majority of the tumors were jugular foramen schwannomas (38%) and trigeminal schwannomas (27%). HSRT was given for 45 patients (86%), whereas CSRT was for 6 (12%) and SRS for 1 (2%). RESULTS: The median pretreatment volume was 9.4 cm3 (range, 0.5752 cm3). With the median follow up time of 36 months (range, 3135), the 3 and 5 year progression free survival was 94 % and 88%, respectively. Tumor size was decreased in 13 (25%), stable in 29 (56%), and increased in 10 (19%). Among the latter, 3 (30%) required additional treatment because of neurologic deterioration. No patient was found to develop any new cranial nerve deficit after SRS/SRT. CONCLUSIONS: These data confirmed that SRS/ SRT provide high tumor control rates with low complications. Large volume tumors and cystic expansion after radiation should be carefully followed up with neurological examination and MRI, because it may frequently cause neurological deterioration requiring further surgery.

Central Spinal Canal Decompression for Lumbar Spondylosis with Uniportal Full-Endoscopic Interlaminar Approach: Technical Note and Preliminary Results in Thailand.

Objective: To describe surgical techniques for central spinal canal decompression with uniportal full-endoscopic interlaminar approach and report preliminary results of the first three cases. Material and Method: Surgical technique for uniportal full-endoscopic interlaminar approach for central spinal canal decompression was described step by step. Three consecutive cases that were operated by this new technique were illustrated by retrospective chart review. Results: All three illustrative cases achieved excellent clinical outcomes in terms of leg pain and claudication without postoperative complications. A follow-up period was two to eight months. Intra-operative blood loss varied from 20 to 50 milliliter. All cases were discharged from the hospital within two days after surgery. Conclusion: Uniportal full-endoscopic interlaminar approach is a viable alternative procedure for central spinal canal decompression with the advantages of smaller skin incision and less tissue trauma. However, studies with larger number of cases and longer follow-up periods are needed in order to make a clear conclusion of the superiority of this new technique comparing to conventional microsurgical laminectomy.

C2 anatomy for translaminar screw placement based on computerized tomographic measurements.

STUDY DESIGN: Anatomical study. PURPOSE: To evaluate the anatomy of the C2 lamina for translaminar screw placement based on computerized tomographic measurements. OVERVIEW OF LITERATURE: C2 translaminar screw insertion is a novel technique for atlanto-axial fixation. The risk of vertebral artery injury can be decreased by this technique. However, a large series of anatomical studies on C2 anatomy in Asian populations is still lacking. METHODS: Two hundred adult C2 vertebrae were evaluated by computerized tomographic imaging. The measured parameters included inner and outer transverse diameters of C2 lamina, C2 laminar length and spino-laminar angle. C2 vertebrae with lamina screw placement feasibility were defined as those with inner transverse diameter larger than 3.5 mm. RESULTS: The mean inner transverse diameter of the C2 lamina was 4.23±1.22 mm. It was significantly larger in males than in females (4.44±1.29 mm vs. 3.96±1.06 mm, p=0.005). The mean outer transverse diameter of C2 lamina was 6.64±1.36 mm. The mean C2 laminar length was 37.26±4.42 mm. The mean C2 spino-laminar angle was 56.42±6.42 degrees. Seventy-nine percents of patients had inner transverse diameter larger than 3.5 mm. CONCLUSIONS: C2 translaminar screw fixation was feasible in the majority of the adult population. However, there were some people who had small C2 lamina. We recommend preoperative computed tomography evaluation to confirm the feasibility of screw placement.

Comparison between minimally invasive and open transforaminal lumbar interbody fusion.

OBJECTIVE: To compare the clinical and radiographic outcomes between minimally invasive and open transforaminal lumbar interbody fusion (TLIF) for treatment of lumbar spondylolisthesis MATERIAL AND METHOD: A retrospective clinical study of24 consecutive cases of lumbar spondylolisthesis treated by minimally invasive TLIF (n = 12) or open TLIF (n = 12) was done at Ramathibodi Hospital between June 2008 and December 2009. The following parameters were compared between the two groups, clinical and radiographic outcomes, blood loss, operative time, length of hospital stay, and complications. RESULTS: The average duration of follow-up was 28 months (range, 24 months to 38 months). There was significantly less intra-operative blood loss in minimally invasive TLIF group comparing to open TLIF group (317 cc vs. 645.83 cc: p-value = 0.04). No significant difference was observed in clinical outcomes (VAS or ODI at 2years), radiographic outcome (91.67% fusion rate in both groups), operative time (340 minutes vs. 324 minutes: p-value = 0.96) length of hospital stay (8.42 days vs. 8.33 days: p-value = 0.09) and major complication (8.33% in both groups) between the two groups. CONCLUSION: Minimally invasive TLIF has similar clinical outcomes and fusion rate compared to open TLIF with additional benefit of less intra-operative blood loss. However the operative field of this technique is limited so thorough knowledge of anatomy in this region is required

Axillary nerve injury associated with sports.

OBJECT: The aim of this retrospective study was to present and investigate axillary nerve injuries associated with sports. METHODS: This study retrospectively reviewed 26 axillary nerve injuries associated with sports between the years 1985 and 2010. Preoperative status of the axillary nerve was evaluated by using the Louisiana State University Health Science Center (LSUHSC) grading system published by the senior authors. Intraoperative nerve action potential recordings were performed to check nerve conduction and assess the possibility of resection. Neurolysis, suture, and nerve grafts were used for the surgical repair of the injured nerves. In 9 patients with partial loss of function and 3 with complete loss, neurolysis based on nerve action potential recordings was the primary treatment. Two patients with complete loss of function were treated with resection and suturing and 12 with resection and nerve grafting. The minimum follow-up period was 16 months (mean 20 months). RESULTS: The injuries were associated with the following sports: skiing (12 cases), football (5), rugby (2), baseball (2), ice hockey (2), soccer (1), weightlifting (1), and wrestling (1). Functional recovery was excellent. Neurolysis was performed in 9 cases, resulting in an average functional recovery of LSUHSC Grade 4.2. Recovery with graft repairs averaged LSUHSC Grade 3 or better in 11 of 12 cases CONCLUSIONS: Surgical repair can restore useful deltoid function in patients with sports-associated axillary nerve injuries, even in cases of severe stretch-contusion injury.

Peroneal nerve injury associated with sports-related knee injury.

OBJECT: This study analyzes 84 cases of peroneal nerve injuries associated with sports-related knee injuries and their surgical outcome and management. METHODS: The authors retrospectively reviewed the cases of peroneal nerve injury associated with sports between the years 1970 and 2010. Each patient was evaluated for injury mechanism, preoperative neurological status, electrophysiological studies, lesion type, and operative technique (neurolysis and graft repair). Preoperative status of injury was evaluated by using a grading system published by the senior authors. All lesions in continuity had intraoperative nerve action potential recordings. RESULTS: Eighty-four (approximately 18%) of 448 cases of peroneal nerve injury were found to be sports related, which included skiing (42 cases), football (23 cases), soccer (8 cases), basketball (6 cases), ice hockey (2 cases), track (2 cases) and volleyball (1 case). Of these 84 cases, 48 were identified as not having fracture/dislocation and 36 cases were identified with fracture/dislocation for surgical interventions. Good functional outcomes from graft repair of graft length < 6 cm (70%) and neurolysis (85%) in low-intensity peroneal nerve injuries associated with sports were obtained. Recovery from graft repair of graft length between 6 and 12 cm (43%) was good and measured between Grades 3 and 4. However, recovery from graft repair of graft length between 13 and 24 cm was obtained in only 25% of patients. CONCLUSIONS: Traumatic knee-level peroneal nerve injury due to sports is usually associated with stretch/contusion, which more often requires graft repair. Graft length is the factor to be considered for the prognosis of nerve repair.

Oculomotor nerve schwannoma: a case report and review of the literature.

BACKGROUND: Oculomotor nerve schwannomas are extremely rare tumors. There are only 40 cases reported in the literature. There is no standard treatment for these rare tumors. CASE REPORT: The authors have reported a case of a 41-year-old Thai man presenting with progressive visual loss of the left eye for 6 months without diplopia. Visual acuity was 20/70 in the right and 20/400 in the left. There was no limitation of eye movement. MRI showed a 42.5 ml mass in the suprasellar region compatible with a schwannoma. The patient underwent a leftpterional craniotomy with partial tumor removal. The pathological section confirmed a diagnosis of schwannoma and the patient received postoperative stereotactic radiotherapy CONCLUSION: Options for treating these rare tumors include clinical observation, surgical resection or stereotactic radiation. High incidence of complete third nerve palsy following surgery has been reported in the literature. Therefore, a subtotal removal of large oculomotor schwannoma followed by stereotactic radiotherapy could provide a safer alternative compared to radical surgery.

Ossification of the posterior longitudinal ligament: a review.

Ossification of the posterior longitudinal ligament (OPLL) is most commonly found in men, the elderly, and Asian patients. There are many diseases associated with OPLL, such as diffuse idiopathic skeletal hyperostosis, ankylosing spondylitis, and other spondyloarthropathies. Several factors have been reported to be associated with OPLL formation and progression, including genetic, hormonal, environmental, and lifestyle factors. However, the pathogenesis of OPLL is still unclear. Most symptomatic patients with OPLL present with neurological deficits such as myelopathy, radiculopathy, and/or bowel and bladder symptoms. There are some reports of asymptomatic OPLL. Both static and dynamic factors are related to the development of myelopathy. Plain radiography, CT, and MR imaging are used to evaluate OPLL extension and the area of spinal cord compression. Management of OPLL continues to be controversial. Each surgical technique has some advantages and disadvantages, and the choice of operation should be made case by case, depending on the patient's condition, level of pathology, type of OPLL, and the surgeon's experience. In this paper, the authors attempt to review the incidence, pathology, pathogenesis, natural history, clinical presentation, classification, radiological evaluation, and management of OPLL.