Establishment of a risk prediction model for olfactory disorders in patients with transnasal pituitary tumors by machine learning.

To construct a prediction model of olfactory dysfunction after transnasal sellar pituitary tumor resection based on machine learning algorithms. A cross-sectional study was conducted. From January to December 2022, 158 patients underwent transnasal sellar pituitary tumor resection in three tertiary hospitals in Sichuan Province were selected as the research objects. The olfactory status was evaluated one week after surgery. They were randomly divided into a training set and a test set according to the ratio of 8:2. The training set was used to construct the prediction model, and the test set was used to evaluate the effect of the model. Based on different machine learning algorithms, BP neural network, logistic regression, decision tree, support vector machine, random forest, LightGBM, XGBoost, and AdaBoost were established to construct olfactory dysfunction risk prediction models. The accuracy, precision, recall, F1 score, and area under the ROC curve (AUC) were used to evaluate the model's prediction performance, the optimal prediction model algorithm was selected, and the model was verified in the test set of patients. Of the 158 patients, 116 (73.42%) had postoperative olfactory dysfunction. After missing value processing and feature screening, an essential order of influencing factors of olfactory dysfunction was obtained. Among them, the duration of operation, gender, type of pituitary tumor, pituitary tumor apoplexy, nasal adhesion, age, cerebrospinal fluid leakage, blood scar formation, and smoking history became the risk factors of olfactory dysfunction, which were the key indicators of the construction of the model. Among them, the random forest model had the highest AUC of 0.846, and the accuracy, precision, recall, and F1 score were 0.750, 0.870, 0.947, and 0.833, respectively. Compared with the BP neural network, logistic regression, decision tree, support vector machine, LightGBM, XGBoost, and AdaBoost, the random forest model has more advantages in predicting olfactory dysfunction in patients after transnasal sellar pituitary tumor resection, which is helpful for early identification and intervention of high-risk clinical population, and has good clinical application prospects.

Improving the accuracy of pre-operative evaluation of neurovascular conflict in trigeminal neuralgia using magnetic resonance subtraction.

PURPOSE: To investigate the ability of magnetic resonance (MR) subtraction to evaluate neurovascular conflict (NVC) and to compare it with conventional MR protocols. METHODS: This prospective study included 82 patients with trigeminal neuralgia who underwent microvascular decompression for NVC. All patients had a pre-operative examination using 3T MRI. The MRI protocols used comprised 3D balanced (B)-fast field echo (FFE), 3D steady-state magnetic resonance angiography (MRA), and 3D T1-FFE sequences. MR subtraction images were obtained by subtracting native images from B-FFE and steady-state MRA. NVC evaluation was performed using subtraction images (MR subtraction) and combination images (conventional MR protocols using B-FFE and T1-FFE in combination). Clinical assessment of the degree of compression, the type of compressing vessel, and the location of conflict were undertaken by two independent observers. The two methods were then compared using surgical criteria. RESULTS: MR subtraction exhibited greater accuracy than the conventional method in terms of the estimated severity of conflict (87.80% vs. 57.32%, p < 0.05), and demonstrated better consistency with surgical findings (k = 0.794 vs. k = 0.365, p < 0.05). For the type of compressing vessel and the location of conflict, both methods were highly accurate and agreed to a similar extent with surgical findings (p = 0.987, compressing vessel; p = 0.665, location of conflict). CONCLUSION: MR subtraction proved reliable in NVC pre-operative evaluation, with increased accuracy when estimating severity. This result strongly supports the wider use of MR subtraction as the preferred choice in clinical application.

Clinical characteristics and treatment outcomes of pigmented tumors in central nervous system: Focusing on melanocytic tumors.

Pigmented tumors are rare neoplasm of central nervous system. Melanocytic tumor, including primary and metastatic lesions, is the most common type. Owing to the rarity, the differential diagnosis of pigmented tumors and clinical management of melanocytic tumor remain challenge. Therefore, focusing on melanocytic tumors, the clinical, radiological, histopathological features and treatment outcomes were presented and analyzed in this study. We identified 22 melanocytic tumors, 2 melanotic medulloblastomas, 2 melanotic ependymomas and 1 melanotic schwannoma. Compared with metastatic melanocytic tumors (MMTs), primary melanocytic tumors (PMTs) were characterized by younger age (36.11 ± 17.96 vs. 51.69 ± 12.58 years, p = 0.0262), lower possibility to be multiple lesions (11.1%vs. 61.5%, p = 0.0306), higher proportion of hypointensity on T2-weighted images (66.7% vs. 15.4%, p = 0.0260) and higher frequency in black appearance (77.8% vs. 23.1%, p = 0.0247). During the follow-up, 4 PMTs and 11 MMTs (71.4%) experienced tumor progression. PMTs had better prognosis than MMTs that progression-free survival (PFS) rate of PMT was 50.0% but decreased to 23.1% for MMTs at 12 months (p = 0.0123). Cox proportional hazards regression revealed that multiplicity of tumor was an independent predictor for PFS. None of patient with multiple tumors was in PFS after 12 months' follow-up whereas PFS rate was 40.5% for single tumor (p = 0.0002). In conclusion, radiological appearances, especially hypointensity on T2-weighted images, might be an indication for PMT. MMTs are more likely to be multiple intraparenchymal masses in elder patients located in supratentorial region. Current treatments included operation, radiotherapy and chemotherapy are not competent to control tumor progression and other therapeutic modalities are urgently needed.

Ultra-Early Treatment for Poor-Grade Aneurysmal Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis.

BACKGROUND: It remains unknown if ultra-early (within 24 hours after onset) treatment can improve the prognosis in patients with poor-grade aneurysmal subarachnoid hemorrhage (aSAH). We aimed to evaluate the effect of ultra-early treatment on functional outcomes and mortality in patients with poor-grade aSAH via a systematic review and meta-analysis. METHODS: We performed a literature search in the PubMed, MEDLINE, and Web of Science databases. Primary outcomes were death and functional outcome assessed at any time period. Secondary outcomes were the rebleeding rate before an aneurysm occlusion procedure and the incidence of intraoperative technique difficulty (ITD). The results are reported as odds ratio (OR) with 95% confidence interval (CI). RESULTS: A total of 14 articles containing 1111 patients met our inclusion criteria and were included in our analysis. The pooled incidence was 47% (95% CI, 40%-54%) for favorable outcome across 13 studies, 26% (95% CI, 19%-32%) for mortality in 11 studies, 10% (95% CI, 3%-16%) for rebleeding in 5 studies, and 20% (95% CI, 10%-31%) for ITD in 5 studies after ultra-early treatment of poor-grade aSAH. Compared with delayed treatment (>24 hours), the ultra-early treatment failed to improve outcomes (OR, 1.23; 95% CI, 0.75-2.01; P = 0.40) or reduce mortality (OR, 0.84; 95% CI, 0.58-1.22; P = 0.45), but tended to prevent preoperative rebleeding (OR, 0.59; 95% CI, 0.32 to 1.07; P = 0.08) in 6, 4, and 4 case-control studies, respectively. CONCLUSIONS: Our findings show no significant change both in functional outcome and mortality between ultra-early and delayed treatment although ultra-early treatment may be associated with lower rebleeding rate.

A colorimetric and absorption ratiometric anion sensor based on indole & hydrazide binding units.

A colorimetric and absorption ratiometric anion sensor (L) based on indole and hydrazide binding units was designed and synthesized, and its recognition & sensing properties towards different anions were studied by naked-eye observations, UV-vis and (1)H NMR titration spectra. Sensor L could selectively recognize biologically important F(-), AcO(-) and H2PO4(-) in DMSO over other anions, along with a significant change in its color and absorption spectrum, resulting from the formation of corresponding 1:2 (L/F(-)) and 1:1 (L/AcO(-) and L/H2PO4(-)) complexes. The (1)H NMR titration experiments proved that sensor L experienced deprotonation of NH fragment and produced [HF2](-) species, whereas a stable H-bonding complex was formed in the presence of AcO(-) and H2PO4(-).

Aquaporin 4 expression and ultrastructure of the blood-brain barrier following cerebral contusion injury.

This study aimed to investigate aquaporin 4 expression and the ultrastructure of the blood-brain barrier at 2-72 hours following cerebral contusion injury, and correlate these changes to the formation of brain edema. Results revealed that at 2 hours after cerebral contusion and laceration injury, aquaporin 4 expression significantly increased, brain water content and blood-brain barrier permeability increased, and the number of pinocytotic vesicles in cerebral microvascular endothelial cells increased. In addition, the mitochondrial accumulation was observed. As contusion and laceration injury became aggravated, aquaporin 4 expression continued to increase, brain water content and blood-brain barrier permeability gradually increased, brain capillary endothelial cells and astrocytes swelled, and capillary basement membrane injury gradually increased. The above changes were most apparent at 12 hours after injury, after which they gradually attenuated. Aquaporin 4 expression positively correlated with brain water content and the blood-brain barrier index. Our experimental findings indicate that increasing aquaporin 4 expression and blood-brain barrier permeability after cerebral contusion and laceration injury in humans is involved in the formation of brain edema.

Microsurgery via modified far-lateral approach for giant dumbbell-shaped jugular foramen tumors.

BACKGROUND AND OBJECTIVE: During the resection of jugular foramen tumors via the basic far lateral approach, the jugular foramen tumor area as well as its adjacent structures, especially the intracranial part, can be better exposed, which avoids stripping of the petrous part of temporal bone and displacement of facial nerve, and protects the patient's hearing from damage. However, when applied in tumors developed from ventral to the brain stem and middle fossa, with extracranial tumors, this surgical approach seems to be inadequate and limited. This study was to explore the microsurgical technique and clinical value for treating giant dumbbell-shaped tumors at jugular foramen (JF) via a modified far lateral approach. METHODS: A retrospective analysis was performed in 16 patients with huge dumbbell-shaped tumors at JF which were removed through the modified far lateral approach (suboccipital transjugular-jugular tubercle-jugular process) between January 2001 and December 2008. The process of operation, and pre-and postoperative clinical data were included in the analysis. RESULTS: Gross total tumor removal was achieved in 14 cases, subtotal removal in 1 case, and partial removal in 1 case. Follow-up examinations in most patients demonstrated that the patient with an obvious preoperative deficit had a good recovery. During the follow-up from three months to seven years, 10 (76.9%) cases with lower cranial nerve involvement showed obvious improvement of symptom after operation, 8 (80.0%) cases with facial palsy obtained various degrees of alleviation, and 7 (77.8%) cases with hearing impairment at different levels restored hearing. Two patients developed new lower cranial nerve palsies after operation, and underwent functional rehabilitation in the three-month follow-up. CONCLUSIONS: Modified far lateral approach is helpful for removing the huge tumors at JF, especially for tumors extending to the petroclival region ventral part of pontomedullary junction. It has a higher rate of total resection, preoperative cranial nerve function impairment is expected to restore, and also has the advantage of protecting the facial nerve, labyrinth and vertebral artery structure from unnecessary damage.