Archives of Neuroscience
Volume:10 Issue: 4, Oct 2023

 Giant vestibular schwannoma (VS) represents one of the most challenging interventions in skull base surgery. Preserving facial and cochlear nerves requires effective surgical planning and nuanced techniques.

 The present study evaluates the role of intraoperative neuromonitoring (IONM) in predicting the outcome of facial and cochlear nerves.

 This retrospective cohort comprised 34 patients with a giant (Samii IV/IVb grade) VS during 2016 - 2019. The retrosigmoid approach was used for tumor resection. Pre- and postoperative facial exams were graded according to the House-Brackmann Scale. Hearing ability was also classified according to the Hannover Hearing Classification. Intraoperative findings included the location of the nerve complex, tumor consistency, the surgical plane of the tumor from the facial nerve/ brainstem, and the level of internal auditory canal (IAC) decompression. Intraoperative neuromonitoring was used for all surgeries. The amplitude required for a positive response was recorded during the facial nerve's direct electrical stimulation (DES). All patients were followed 6 and 12 months postoperative.

 The preoperative facial nerve function was normal in 91.2% of patients, and 8.8% had slight facial nerve impairment (FNI). Considering preoperative hearing status, 9 cases (26.5%) had moderate hearing loss or impairment, while 25 patients (73.5%) complained of severe hearing impairment. The mean intraoperative direct facial nerve stimulation threshold was 1.38 ± 0.89. Hearing impairment was moderately severe in 7 (20.6%) and severe in 25 patients (73.5%) postoperation. In addition, postoperative assessment revealed 13 (38.2%) cases with moderate FNI and 12 (35.2%) with moderately severe FNI. The tumor size did not affect the postoperative hearing loss, and the postoperative hearing loss did not improve significantly (P = 0.32). There was no statistically significant correlation between the intensity of intraoperative DES and postoperative facial nerve function (P > 0.05). No significant correlation was observed between tumor consistency and postoperative hearing status (P > 0.05).

 The retrosigmoid approach combined with IONM appears to be associated with favorable facial and cochlear nerve outcomes in giant VS. The postoperative facial nerve function may improve, but sensorineural hearing status may not improve significantly. Moreover, the intensity of intraoperative DES may not predict the postoperative facial function. Therefore, the findings of IONM should be interpreted carefully.

During pregnancy, SARS-CoV-2 infection (COVID-19) can be complicated, and the mother and neonate's prognosis is not fully documented. We are presenting the case of a 33-week pregnant patient with confirmed COVID-19 who developed encephalopathy. During the disease and hospitalization in a critical care setting, an emergency C-section was performed with general anesthesia in the ICU due to acidosis and maternal-fetal instability. The baby boy was delivered with an APGAR score of 8, showing no obvious anomalies, and was subsequently intubated. Eight days later, brain imaging revealed posterior reversible encephalopathy syndrome. The mother received treatment and was discharged without further complications. At the final follow-up six months after discharge, the patient's MRI showed laminar necrosis in the two occipitoparietal cortex areas. However, she remained symptom-free and did not report any complications. We also discussed the possible reasons for these findings and their relationship to the infection.

 Delirium is a common concern among elderly intensive care unit (ICU) patients. Ketamine’s effectiveness in preventing delirium remains controversial despite its demonstrated neuroprotective properties and cognitive benefits in previous studies.

 This study aimed to compare the safety and efficacy of ketamine and haloperidol in preventing delirium in elderly ICU patients.

 This randomized clinical trial involved 44 non-intubated patients aged over 65 years in a general ICU. The patients received low-dose intravenous ketamine (20 mg) or intramuscular haloperidol (2.5 mg). Delirium was assessed using the Richmond Agitation Sedation Scale (RASS) at 5, 10, and 15 minutes. The primary outcome was the percentage of patients achieving adequate sedation (RASS ≤ +1). The secondary outcome was time to reach adequate sedation. Adverse effects and physician satisfaction were evaluated after 60 minutes.

 No significant difference in delirium was observed between the groups after interventions or within each group over time. However, the ketamine group had significantly lower delirium incidence at 5 minutes. The percentage of patients achieving adequate sedation was higher in the ketamine group (86.4%) than in the haloperidol group (36.4%) (P = 0.002). There was a delirium difference between groups at 10 minutes (P = 0.31) or 15 minutes (P = 0.082). Physician satisfaction did not differ significantly (P = 0.144).

 The present study suggests that the administration of low-dose ketamine to elderly ICU patients might reduce delirium incidence, supporting its beneficial effect for delirium control.

 Coronavirus disease 2019 (COVID-19), as a global crisis, has impacted all aspects of human life, even long after its universal containment. Among these impacts, COVID-related cognitive disorders (CDs) are significant, particularly when they persist over the long term. Cognitive disorders are characterized by the brain’s inability to process, store, and utilize information for reasoning, judgment, perception, attention, comprehension, and memory.

 Given the persistence of COVID-related CDs even long after recovery, this study aimed to determine the prevalence and predictive factors of CDs among individuals who had recovered from COVID-19 in Iran, using Bayesian analysis.

 In this regional cross-sectional analytical study, 300 individuals were randomly selected from three hospitals in Tehran, Iran. The subjects were evaluated using the Clinical Demographic Information Questionnaire, Montreal Cognitive Assessment (MoCA), the Pittsburgh Sleep Quality Index (PSQI), the Obsessive-Compulsive Inventory-Revised (OCI-R), the Depression, Anxiety, and Stress Scale 21 (DASS-21), and the Posttraumatic Stress Disorder (PTSD) Checklist for DSM-5 (PCL-5). The obtained data were analyzed using SPSS software (version 26) to determine the prevalence of CDs, identify predictive factors, and examine the interrelationship between CDs and other COVID-related disorders.

 Among the 300 participants, only 81 individuals (27%) exhibited CDs. The majority of the aforementioned subjects were patients at hospital A (46.91%), and their recovery occurred between 12-18 months ago (39.51%). Among these variables, only the difference in the hospital variable was statistically significant (P = 0.001). Furthermore, there were correlations between CDs and obsessive-compulsive disorder (OCD), anxiety, and stress, although they were not statistically significant. Ultimately, PTSD (BF = 0.58, P = 0.02), older age (BF = 0.0001, P = 0.0001), hospitalization at hospital A (BF = 0.35, P = 0.001), lower arterial oxygen saturation (SaO2) (BF = 0.01, P = 0.0001), and longer hospitalization (BF = 0.001, P = 0.0001) were identified as the most robust predictors for the presence of CDs among individuals recovering from COVID-19.

 In conclusion, CDs were observed in less than half (27%) of individuals who had recovered from COVID-19. Sociodemographic and health disparities contributed to variations in the prevalence, severity, and significance of these disorders.

 Chronic stress causes a deleterious impact on older adults and accelerates the aging process through different mechanisms, such as increased oxidative stress. Metformin, a drug with pleiotropic effects, exhibited neuroprotective and antioxidant properties.

 Our study aimed to investigate the metformin effects on aging under stress conditions.

 Old male rats (18 months) were divided into 6 experimental groups (N = 8): 1 = control; 2 and 3 = metformin (1 or 10 mg/kg, orally, 40 days); 4 = stress (40 days); 5 and 6 = stress + metformin (1 or 10 mg/kg, orally, 40 days). Chronic variable stress was induced with 7 types of stressors for 40 days. Neurobehavioral functions were evaluated using the Morris water maze, Y-maze, elevated plus maze, open field, forced swimming test, rotarod, and exhausting swimming test. In addition, BDNF level and SOD activity were measured.

 Stress induction increased memory deficits, anxiety, depression, and muscle fatigue in old rats. Metformin (10 mg/kg) enhanced memory performance and muscle strength and diminished anxiety and depression in stressed animals (P < 0.05). Treatment with metformin increased the BDNF brain level and SOD activity (P < 0.05).

 Metformin restored neurobehavioral disruptive changes induced by chronic stress in old rats. The underlying mechanisms could be related to the prevention of oxidative stress and neuronal damage and elevation of BDNF levels in the brain.

The sphenopalatine ganglion nerve block (SPGB) in endoscopic sinus surgeries has beenshownto reduce postsurgery narcotic consumption.

This study aimed to investigate the effect of SPGB on bleeding and pain during and after rhinoplasty and septoplasty.

This study was conducted as a double-blind, randomized clinical trial and included 30 patients who were scheduled for elective rhinoplasty and septoplasty. All the participants received propofol/remifentanil anesthesia and similar intraoperative care. The patients were divided into 2 groups: the SPGB group, which received 0.5% bupivacaine, and the placebo group, which received normal saline. The study compared the amount of narcotics used during and after the operation, pain levels during and after the operation (at 2, 4, 6, and 24 hours after the operation), and bleeding during the operation between the 2 groups. The surgeon’s satisfaction with bleeding control was also recorded at 30, 60, and 90 minutes.

In the SPGB group, 86% of the participants had ASA (American Society of Anesthesiologists) class I, while in the placebo group, 80% had ASA class I. There was no significant difference in postoperative pain between the control and intervention groups (P> 0.05). However, the SPGB group showed a significant decrease in intraoperative pain based on the amount of narcotics received (P < 0.05). According to the Boezaart criterion, the control group had significantly higher rates of severe and moderate bleeding (P < 0.05), whereas the bupivacaine group had a lower total bleeding rate (P < 0.05).

The administration of bupivacainewaseffective in reducing pain, bleeding, andthe need for narcotics during surgery. The SPGB has the potential to decrease bleeding and drug utilization, making it a preferable option for anesthesiologists aiming to minimize the use of anesthetics.

Postoperative cognitive dysfunction (POCD) is a significant complication, especially prevalent among elderly individuals following major surgical procedures.

This study aims to compare the impact of isoflurane and propofol on the occurrence of POCD in patients undergoing elective laminectomy surgery under general anesthesia.

This randomized, double-blind clinical trial took place at Shariati Hospital in Tehran. Patients scheduled for elective laminectomy between December 2020 and November 2021 were enrolled in the study and randomized into 2 groups. Patients in Group P received a Propofol infusion, while patients in Group I were administered isoflurane. Cognitive function assessments were conducted using the Mini-Mental State Examination (MMSE) at 3-time points: Twelve hours before surgery and 6 and 24 hours after surgery.

TheMMSEscores demonstrated a significant increase in the Propofol group compared to the Isoflurane group at the 6-hour and24-hour post-surgery time points. However, nosignificant differencewasobserved at baseline before surgery (P=0.04, P=0.005, and P = 0.2, respectively).

These findings suggest that the use of propofol for general anesthesia may be a favorable choice for surgical procedures in elderly patients.

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019 led to the global coronavirus disease 2019 (COVID-19) pandemic with a wide range of clinical symptoms. Neurological complications have been a significant concern, with diverse symptoms and potential neuroinvasive mechanisms. The pandemic has also impacted individuals with mental health conditions, such as migraines, bipolar disorder (BD), and schizophrenia, highlighting the complex interconnections between physical and mental health during these challenging times.

This retrospective report from the Iranian Network for Research in Viral Diseases (INRVD) study aimed to investigate the multifaceted interactions between COVID-19, neurological complications, and mental health disorders (e.g., migraines, BD, and schizophrenia) to better understand their collective impact on individuals’ health and well-being.

This study involved 63 individuals who tested positive for COVID-19, including 32 females (50.8%) and 31 males (49.2%). The participants were categorized into different groups based on their underlying conditions: 7 individuals with schizophrenia, 8 with BD, 6 with migraines, 12 with Alzheimer’s disease, and 30 with COVID-19 without any underlying neurologic disorder. This investigation was carried out in 12 hospitals supervised by the INRVD between March 2020 and May 2021. The study used frequencies and percentages to describe the data and employed chi-square tests, including the contingency coefficient, to explore associations between COVID-19 symptoms and disease groups.

The analysis of clinical manifestations revealed distinctive patterns. Cough was the most prevalent symptom across the entire sample, affecting over 79% of participants. Fever followed as the second most common symptom, with approximately 62% of individuals reporting it. Fatigue ranked third, impacting 57% of the subjects. In contrast, vomiting was the least frequently reported symptom, with an incidence of only 14.3%. In terms of specific conditions, a notable discrepancy was observed in the prevalence of headaches. Although present in 71.4% of individuals with schizophrenia, this symptom was reported by only 50% of those with BD, followed by 66.7% with migraines and 83.3% with Alzheimer’s. The patients without neurologic disorders exhibited a lower incidence of neurological manifestations, with only 23.3% reporting headaches.

This study provides insights into the clinical manifestations of COVID-19 in individuals with distinct underlying conditions. The prevalence and presentation of symptoms varied significantly across the different groups, and neurological symptoms exhibited a higher prevalence in this patient group than those without any underlying neurologic disorders. This study aimed for a more comprehensive understanding of the probable intricate interplay between COVID-19, underlying health conditions, and clinical manifestations. Understanding these differences is crucial for tailoring effective clinical interventions.