Epilepsy surgery for dominant-side mesial temporal lobe epilepsy without hippocampal sclerosis.

Although anterior temporal lobectomy (ATL) is an established surgery for medically intractable mesial temporal lobe epilepsy (MTLE), it can harm memory function, especially in dominant-side MTLE patients without hippocampal sclerosis (HS). To avoid this complication, multiple hippocampal transection (MHT) was developed, but its efficacy has not been fully elucidated. We report the detailed treatment results of MHT compared with that of ATL. We retrospectively analysed the records of 30 patients who underwent surgery for dominant-side MTLE. ATL was completed for 23 patients with HS, and MHT was completed for 7 patients without HS. The seizure control status, number of anti-seizure medicines, neurocognitive function, and psychiatric disorders of each patient were reviewed. The mean follow-up period was 70 months. Seizure control of Engel class I was achieved in 16 patients (70%) in the ALT group versus 5 patients (71%) in the MHT group. The mean number of anti-seizure medicines administered in the ATL group changed significantly from 2.4 to 1.9 (p = 0.01), while that in the MHT group was unchanged (from 2.1 to 2.0, p = 0.77). Eleven patients (48%) in the ATL group developed psychiatric disorders during the postoperative follow-up period, whereas no psychological complications were observed in the MHT group. Neither group showed neurocognitive decline after the surgery in any of the WAIS-III or WMS-R subtests. In conclusion, MHT may achieve reasonable postoperative seizure reduction, preserve neurocognitive function, and reduce postoperative psychiatric complications. Therefore, it can be considered as a therapeutic option for dominant-side MTLE without HS.

A New Technique for the Endoscopic Reconstruction of Skull Base Defects Using Multiple-balloon Catheters.

Cerebrospinal fluid (CSF) leakage is a major complication following endoscopic endonasal skull base surgery. Various skull base reconstruction methods are available, and the use of a vascularized nasoseptal flap (NSF) in skull base reconstruction has greatly contributed to a decrease in the CSF leak rate. A balloon catheter such as a sinus balloon or a Foley catheter is often used to support an NSF; however, in cases wherein nasal and/or paranasal structures supporting the balloon are lacking following the surgery, the NSF is not properly fixed and postoperative CSF leak may occur. Here we introduce a new technique of using multiple-balloon catheters to fix an NSF in such cases and provide the results of our analysis of the new technique's efficacy. Eight patients who underwent endonasal endoscopic surgery for the following cases were included: olfactory neuroblastoma (n = 6), recurrent craniofacial meningioma (n = 1), and recurrent chordoma (n = 1). After tumor resection, multilayered reconstruction with vascularized NSF was performed. Given that the Foley catheter was not stable to fix the flap in each case, we used an additional nasal catheter to support the Foley catheter. No complications such as postoperative CSF leak and necrosis of the vascularized flap were observed. These results suggest that the multiple-balloon catheter technique is a useful method for fixing the NSF to the skull base even when nasal cavity structures are missing due to surgical removal.

A Prehospital Triage System to Detect Traumatic Intracranial Hemorrhage Using Machine Learning Algorithms.

Importance: An adequate system for triaging patients with head trauma in prehospital settings and choosing optimal medical institutions is essential for improving the prognosis of these patients. To our knowledge, there has been no established way to stratify these patients based on their head trauma severity that can be used by ambulance crews at an injury site. Objectives: To develop a prehospital triage system to stratify patients with head trauma according to trauma severity by using several machine learning techniques and to evaluate the predictive accuracy of these techniques. Design, Setting, and Participants: This single-center retrospective cohort study was conducted by reviewing the electronic medical records of consecutive patients who were transported to Tokyo Medical and Dental University Hospital in Japan from April 1, 2018, to March 31, 2021. Patients younger than 16 years with cardiopulmonary arrest on arrival or with a significant amount of missing data were excluded. Main Outcomes and Measures: Machine learning-based prediction models to detect the presence of traumatic intracranial hemorrhage were constructed. The predictive accuracy of the models was evaluated with the area under the receiver operating curve (ROC-AUC), area under the precision recall curve (PR-AUC), sensitivity, specificity, and other representative statistics. Results: A total of 2123 patients (1527 male patients [71.9%]; mean [SD] age, 57.6 [19.8] years) with head trauma were enrolled in this study. Traumatic intracranial hemorrhage was detected in 258 patients (12.2%). Among several machine learning algorithms, extreme gradient boosting (XGBoost) achieved the mean (SD) highest ROC-AUC (0.78 [0.02]) and PR-AUC (0.46 [0.01]) in cross-validation studies. In the testing set, the ROC-AUC was 0.80, the sensitivity was 74.0% (95% CI, 59.7%-85.4%), and the specificity was 74.9% (95% CI, 70.2%-79.3%). The prediction model using the National Institute for Health and Care Excellence (NICE) guidelines, which was calculated after consultation with physicians, had a sensitivity of 72.0% (95% CI, 57.5%-83.8%) and a specificity of 73.3% (95% CI, 68.7%-77.7%). The McNemar test revealed no statistically significant differences between the XGBoost algorithm and the NICE guidelines for sensitivity or specificity (P = .80 and P = .55, respectively). Conclusions and Relevance: In this cohort study, the prediction model achieved a comparatively accurate performance in detecting traumatic intracranial hemorrhage using only the simple pretransportation information from the patient. Further validation with a prospective multicenter data set is needed.

Microsurgical Resection of a Large Dumbbell-Shaped Jugular Foramen Schwannoma via Infralabyrinthine, Retrofacial, and Transjugular Approach.

Surgical removal of large jugular foramen schwannomas with intra- and extracranial extension is challenging. The treatment goal is a gross total resection of the tumor without causing surgical complications, including facial nerve paresis, hearing disturbance, dysphagia, hoarseness, and cerebrospinal fluid (CSF) leakage, in addition to the brain stem injury. We present a surgical video in a patient with a dumbbell-shaped glossopharyngeal schwannoma. The combination of posterior fossa craniotomy, mastoidectomy, and unroofing of the jugular foramen with high cervical exposure was selected. Although transposition of the mastoid segment of the facial nerve provides an excellent surgical corridor, it may affect normal facial nerve function. Sufficient drilling of the infralabyrinthine, retrofacial area of the mastoid without facial nerve transposition is important for the safe gross total removal of the tumor. Subcapsular removal behind the jugular vein is also important for preservation of the lower cranial nerve functions. The patient underwent a gross total removal of the tumor ( Figs. 1 and 2 ). Facial nerve function was preserved and hearing disturbance improved. Although dysphagia and hoarseness complicated postoperatively, he became able to take foods orally 16 days after the surgery. In summary, successful removal of a large dumbbell-shaped jugular foramen tumor can be completed via infralabyrinthine, retrofacial, and transjugular approach without facial nerve transposition. The link to the video can be found at: https://youtu.be/U4CwOW78id4 .

Detection of hemodynamic impairment on 15O gas PET using visual assessment of arterial spin-labeling MR imaging in patients with moyamoya disease.

It is unclear whether the visual assessment of noninvasive arterial spin labeling magnetic resonance imaging (ASL) can identify instances of hemodynamic compromise including an elevated oxygen extraction fraction (OEF) measured by 15O-gas positron emission tomography (PET). Here we evaluated the relationship between a four-point visual assessment system referred to as 'ASL scores' using ASL with two postlabeling delays (PLDs; 1525 ms and 2525 ms) and some quantitative hemodynamic parameters measured by PET. We retrospectively evaluated the cases of 18 Japanese patients with moyamoya disease who underwent ASL and PET. We compared the patients' regional ASL scores on two ASL images to the regional values of PET parameters, and we observed a significant trend in accord with the presumed clinical severity among all PET parameters and ASL scores (p < .003). The ASL score of the long PLD (2525 ms) showed the highest specificity (98.5%) for elevated OEF. Our results suggest that hemodynamic impairment (including elevated OEF) in patients with moyamoya disease may be grossly assessed by a visual assessment of noninvasive ASL images, which can be easily obtained in clinical settings.