Hypoxic Bone Mesenchymal Stem Cell-Derived Exosomes Direct Schwann Cells Proliferation, Migration, and Paracrine to Accelerate Facial Nerve Regeneration via circRNA_Nkd2/miR-214-3p/MED19 Axis

Background

Facial nerves have the potential for regeneration following injury, but this process is often challenging and slow. Schwann cells (SCs) are pivotal in this process. Bone mesenchymal stem cells (BMSC)-derived exosomes promote tissue repair through paracrine action, with hypoxic preconditioning enhancing their effects. The main purpose of this study was to determine whether hypoxia-preconditioned BMSC-derived exosomes (Hypo-Exos) exhibit a greater therapeutic effect on facial nerve repair/regeneration and reveal the mechanism.

Methods

CCK-8, EdU, Transwell, and ELISA assays were used to evaluate the functions of Hypo-Exos in SCs. Histological analysis and Vibrissae Movements (VMs) recovery were used to evaluate the therapeutic effects of Hypo-Exos in rat model. circRNA array was used to identify the significantly differentially expressed exosomal circRNAs between normoxia-preconditioned BMSC-derived exosomes (Nor-Exos) and Hypo-Exos. miRDB, TargetScan, double luciferase assay, qRT-PCR and WB were used to predict and identify potential exosomal cirRNA_Nkd2-complementary miRNAs and its target gene. The function of exosomal circRNA_Nkd2 in facial nerve repair/regeneration was evaluated by cell and animal experiments.

Results

This study confirmed that Hypo-Exos more effectively promote SCs proliferation, migration, and paracrine function, accelerating facial nerve repair following facial nerve injury (FNI) compared with Nor-Exos. Furthermore, circRNA analysis identified significant enrichment of circRNA_Nkd2 in Hypo-Exos compared with Nor-Exos. Exosomal circRNA_Nkd2 positively regulates mediator complex subunit 19 (MED19) expression by sponging rno-miR-214-3p.

Conclusion

Our results demonstrated a mechanism by which Hypo-Exos enhanced SCs proliferation, migration, and paracrine function and facial nerve repair and regeneration following FNI through the circRNA_Nkd2/miR-214-3p/Med19 axis. Hypoxic preconditioning is an effective and promising method for optimizing the therapeutic action of BMSC-derived exosomes in FNI.

[Epidemiological investigation of constipation in urban areas of Hangzhou, China]

Objective: To determine the prevalence and risk factors of constipation in Hangzhou urban areas by analyzing data from a recent epidemiological survey. Methods: From August 2022 to June 2023, a cross-sectional survey was conducted on 43 communities on eight streets in suburbs of Hangzhou, including Wangjiang, Sijiqing, Puyan, Changhe, Ziyang, Xiaoshanchengxiang, Zhuantang, and Banshan. Written questionnaires were filled out face to face by community doctors. The prevalence of constipation was investigated using a combination of the Bristol stool typing method and the Rome IV criteria. The risk factors for constipation were analyzed using multivariate logistic regression analysis. Results: The study cohort comprised 10,479 participants, 5551 of whom were male (53.0%) and 4928 female (47.0%). The overall prevalence of constipation was 10.6% (1107/10,479). The prevalence was 11.0% (613/5551) for male and 10.0% (494/4928) for female participants; this difference is not statistically significant (P>0.05).There were no significant differences in the prevalence of constipation between different categories of body mass index (P>0.05). The prevalence of constipation was highest in individuals aged 70 years and above, accounting for 15.4% (264/1717) of all cases. There were significant differences in the prevalence of constipation between different occupations, marital statuses, and educational levels (P<0.001). Patients with hypertension or diabetes mellitus had a higher prevalence of constipation than those without these conditions, those who had been taking long-term medication had a higher prevalence of constipation than those who did not, parents of children with constipation had a higher prevalence of constipation than those with children who did not have constipation, and there were other significant differences in various variables (P<0.001). Multivariate logistic regression analysis of modifiable factors revealed that eating less fruit (OR=1.284, 95%CI: 1.061-1.553, P=0.010), liking spicy and salty food (OR=1.234, 95%CI: 1.039-1.466, P=0.016), sleeping for too long (OR=1.644, 95%CI: 1.260-2.144, P<0.001), irregular sleep patterns (OR=1.370, 95%CI: 1.127-1.665, P=0.002) and minimal exercise (OR=1.388, 95% CI: 1.168-1.649, P<0.001) were all risk factors for constipation; whereas mix diets (OR=0.709,95%CI:0.608-0.826, P<0.001), meat diets (OR=0.604,95%CI: 0.495-0.736, P<0.001), moderate alcohol consumption (OR=0.659, 95% CI: 0.534-0.812, P<0.001), less or no drinking (OR=0.523, 95% CI: 0.428-0.638, P<0.001), and non-smoking (OR=0.819, 95%CI:0.674-0.995, P<0.001) protected against constipation. We found no association between dietary preferences and the risk of constipation (refined grains: OR=1.147, 95%CI:0.944-1.393, P=0.167; no specific preference: OR=0.935, 95%CI:0.783-1.117, P=0.459). The rate of agreement between self-evaluation of constipation by the respondents and objective criteria was higher for negatives (95.8%) than for positives (38.0%). Conclusion: The prevalence of constipation is relatively high in the urban population of Hangzhou. A good lifestyle and diet can significantly reduce its incidence. There should be more emphasis on preventive education, promotion of prevention of constipation, and advocacy for a healthy lifestyle.

Knockdown of protein interacting with C α kinase 1 aggravates sepsis-induced acute liver injury by regulating the TLR4/NF-κB pathway

Acute liver injury (ALI) may manifest at any phase of sepsis, yet an explicit therapeutic approach remains elusive. In this study, LPS and cecum ligation and puncture (CLP) were utilized to establish an inflammatory cell model and a murine model of sepsis-induced liver injury, respectively, aiming to explore the potential protective effect of protein interacting with C α kinase 1 (PICK1) on sepsis-induced ALI and its underlying mechanisms. In both the cell supernatant and the murine whole blood, the concentrations of inflammatory factors were quantified by ELISA, while the protein and mRNA expressions of PICK1, cleaved-PARP-1, caspase1, TLR4, IκBα, and NF-κB were assessed via western blot and qRT-PCR. The outcomes revealed that the knockdown of PICK1 increased the levels of inflammatory factors and apoptosis, alongside activation of TLR4/NF-κB signaling pathway-related factors in both in vivo and in vitro models. Moreover, the murine liver samples were subjected to Hematoxylin-Eosin (HE) staining for assessment of histopathological morphology. The HE staining and liver injury scoring results manifested a markedly exacerbated hepatic damage in PICK1 knockout mice as compared to WT mice following CLP. Furthermore, the liver macrophages were isolated from murine livers, and the expression and activity of the factors associated with the TLR4/NF-κB signaling pathway were verified through RT-qPCR and western blot, and EMSA assay demonstrated an augmented NF-κB activity subsequent to PICK1 knockout. Finally, the expression and localization of PICK1 in macrophages were further scrutinized via immunofluorescence, and the interaction between PICK1 and TLR4 was identified through co-immunoprecipitation. In conclusion, the knockdown of PICK1 appeared to modulate inflammatory factors by activating the TLR4/NF-κB signaling pathway, thereby exacerbating hepatic damage induced by sepsis.

Modified hypoglossal-facial nerve anastomosis for peripheral-type facial palsy caused by pontine infarction: A case report and literature review

Background

Peripheral-type facial palsy could be caused by a lesion in the tegmentum of the pons, such as infarction, with a rare occurrence. We herein described a case of unilateral peripheral-type facial palsy induced by dorsolateral pontine infarction and treated this patient using modified hypoglossal-facial nerve anastomosis.

Case presentation

A 60-year-old female presented with dizziness, hearing drop, diplopia, and peripheral-type facial palsy. Brain Magnetic Resonance Imaging showed a dorsolateral pontine infarction on the right side which exactly refers to the location of the ipsilateral facial nucleus or facial nerve fascicles at the pons. Subsequent electrophysiological examinations confirmed poor facial nerve function of this patient and modified hypoglossal-facial nerve anastomosis was then performed.

Conclusions

This case reminded medical practitioners not to ignore the possibility of involvement of a central cause in peripheral-type facial palsy patients. In addition, modified hypoglossal-facial nerve anastomosis served as a useful skill improvement that may help reduce hemiglossal dysfunction while restoring facial muscle function.

Ultrasound-Guided Oblique Sagittal Anterior Quadratus Lumborum Block in Total Hip Arthroplasty: A Randomized Controlled Trial

BACKGROUND

The anterior quadratus lumborum block (QLB) is gaining popularity in total hip arthroplasty (THA) surgeries for postoperative pain management and this technique rarely results in lower limb muscle weakness. However, no studies have described the range of its blockade.

OBJECTIVES

The aim of the study was to confirm the range of cold temperature sensory blockades, observe the opioid consumption after THA surgery, assess the pain of the patients, and assess the safety of this technique.

STUDY DESIGN

Randomized controlled study.

SETTING

Taizhou Hospital of Zhejiang Province.

METHODS

Patients who underwent primary THAs were randomized to take an oblique sagittal anterior QLB with 30 mL of 0.375% ropivacaine (QLB+G group) or with 30 mL of 0.9% saline (G group). The main purpose of the study was to confirm the range of cold hypoesthesia. The other aim included the average blood pressure, heart rate, surgical pleth index, and bispectral index values fluctuation during the intraoperative period of expanding the medullary cavity, the sufentanil, and remifentanil consumption during the operation, the amount of time the patients stayed in the Postanesthesia Care Unit, the 8 hours, 16 hours, and 24 hours total dosage of oxycodone, the resting and exercise Visual Analog Scale (VAS) pain scores at 8 hours, 16 hours, and 24 hours after surgery, postoperative adverse events, and safety.

RESULTS

The QLB+G group identified areas  of cold hypoesthesia after the block, but there were no areas of cold hypoesthesia in the G group. The consumption of oxycodone in the 8 hours, 16 hours, and 24 hours after the surgery and the consumption of sufentanil during the surgery were significantly smaller in the QLB+G group (P < 0.05). The QLB+G group have lower pain scores at the resting 8 hours and exercise 8 hours, 16 hours, and 24 hours after the surgery (P < 0.05). The 2 groups have comparable safety in the study.

LIMITATIONS

This study only tested the areas of cold hypoesthesia after the QLB, but not tested the area of sensory loss. Using ice to test for hypoesthesia is subjective, and may not reflect the actual area of the block.

CONCLUSIONS

Ultrasound-guided oblique sagittal anterior QLB can reduce the analgesics required after and during THA and the postoperative VAS pain scores, but it rarely affects muscle strength.

Semi-conductive, Switchable Dielectric and Photoluminescent Properties of Two High-Temperature Phase Transition Hybrids

Bistable switches (electrical switching between "ON" and "OFF" bistable states) have gradually developed into an ideal category of highly intelligent materials, due to their significant applications in optical technology, signal processors, data storage and other switchable media applications in the field of electrical devices. Here, we successfully designed and synthesized [(FC₆ H₄ C₂ H₄ NH₃ )₂ MCl₄ ]_n (FC₆ H₄ C₂ H₄ NH₃ ⁺ )=deprotonated 4-fluoro- phenethylamine; M=Cd (1), Mn (2)), which realized the coupling of thermo-dielectric switching characteristics, semi-conductor characteristics and photo-luminescent properties. DSC (differential scanning calorimetry) and dielectric measurements show that 1 is a sensitive dielectric bistable switch between the high dielectric (ON) and low dielectric (OFF) states. The temperature-variable single crystal structure shows that the both 1 and 2 undergo a high-temperature reversible phase transition around 383 K/380 K, which is caused by the order-disordered transformation of organic cations and the slight distortion of the inorganic framework. In particular, 1 shows outstanding switchable dielectric behavior and semiconducting properties. Further, 1 and 2 emit strong green and yellow luminescence at 527 and 595 nm, respectively.

Blink reflex monitoring in microvascular decompression for trigeminal neuralgia

Aim: To determine the value of the blink reflex in evaluating trigeminal sensory function during microvascular decompression for trigeminal neuralgia.Methods: The blink reflex (BR) in 103 patients with primary typical trigeminal neuralgia treated by microvascular decompression (MVD) was tested pre- and intraoperatively. The changes in BR were recorded. All patients underwent general anesthesia with intravenous propofol and fentanyl. Surgical efficacy and complications were evaluated after surgery. The relationship between intraoperative changes in the BR and postoperative trigeminal sensory function was analyzed.Results: The BR was elicited in all patients before surgery, and no significant difference was found between the affected side and the contralateral side. In 93 of the 103 cases, the BR was successfully elicited during MVD surgery. Therefore, the recordability of the BR was 90.29%. R1 latency on the affected side and the contralateral side were 11.62 ± 4.96 ms and 11.66 ± 4.37 ms, respectively. During MVD surgery, R1 of the BR disappeared on the affected side in 7 cases and remained in 86 cases. After the operation, 98 of the 103 patients had immediate and complete remission of trigeminal neuralgia symptoms, and 5 cases had partial remission. The 7 patients whose R1 disappeared during the surgery all experienced facial numbness postoperatively. Of the 86 patients whose R1 remained, only 2 patients had postoperative facial numbness. Of the 10 patients whose R1 was not recordable during the operation, one complained of postoperative facial numbness. No patients had complications such as facial paralysis, cerebrospinal fluid leakage, and death.Conclusions: Conclusion: The blink reflex may allow monitoring of trigeminal sensory function during microvascular decompression under general anesthesia.

Multifunctional rare earth molecular ferroelectrics with a piezoelectric response: ((nBu)4N)3[Ce(NO3)4(SCN)2]((CH3CH2CH2CH2)4N = tetrabutylammonium)

A new type of multipolar rare earth molecular ferroelectric: ((nBu)4N)3[Ce(NO3)4(SCN)2] (BuCH3CH2CH2CH2)4N), undergoes a high-temperature ferroelectric phase transition, possesses flexible switchable SHG effect, moderate spontaneous polarization and a narrow band gap.

Protective effect of dexmedetomidine against diabetic hyperglycemia-exacerbated cerebral ischemia/reperfusion injury: An in vivo and in vitro study

AIMS

Dexmedetomidine (Dex) has been noted to have neuroprotective effect against cerebral ischemia-reperfusion (I/R) injury. However, the effect of Dex in diabetic hyperglycemia-exacerbated cerebral I/R injury and its underlying mechanism remain unclear.

MAIN METHODS

The infarct volume and brain edema were evaluated by 2,3,5-triphenyltetrazolium chloride staining and standard wet-dry method. Modified neurological severity score was utilized to assess the neurological deficits. The oxidative stress and inflammation were evaluated by detecting reactive oxygen species (ROS), malondialdehyde (MDA), tumor necrosis factor (TNF)-α and interleukin (IL)-1β. Terminal deoxynucleotidyl transferase dUTP nick end labeling assay and cell count kit-8 were applied to measure cell apoptosis and viability.

KEY FINDINGS

Dex treatment reduced infarct volume, decreased brain water content and improved neurological deficit in middle cerebral artery occlusion/reperfusion (MCAO/R) mice. Dex treatment reduced the levels of ROS, MDA, TNF-α and IL-1β in the entire middle cerebral artery territory of diabetic mice subjected to MCAO/R, as well as in primary culture of mouse hippocampal neurons stimulated with 50 mM glucose and oxygen glucose deprivation/reperfusion. Dex treatment inhibited neuronal apoptosis induced by diabetic hyperglycemia-exacerbated cerebral I/R injury. Dex upregulated nuclear factor of activated T-cells 5 (NFAT5) and Sirtuin 1 (SIRT1) expression, induced NF-E2-related factor 2 (Nrf2) translocation from cytoplasm to nucleus and inhibited the acetylation of Nrf2. However, these changes triggered by Dex treatment were abrogated by NFAT5 knockdown.

SIGNIFICANCE

Dex protects against diabetic hyperglycemia-exacerbated cerebral I/R injury through attenuation of oxidative stress, inflammation and apoptosis. The underlying mechanism is at least the NFAT5/SIRT1/Nrf2 signaling pathway dependent.

Higgs Mode of Planar Coupled Spin Ladders and its Observation in C_{9}H_{18}N_{2}CuBr_{4}

Polarized inelastic neutron scattering experiments recently identified the amplitude (Higgs) mode in C_{9}H_{18}N_{2}CuBr_{4}, a two-dimensional near-quantum-critical spin-1/2 two-leg ladder compound, which exhibits a weak easy-axis exchange anisotropy. Here, we theoretically examine the dynamic spin structure factor of such planar coupled spin-ladder systems using large-scale quantum Monte Carlo simulations. This allows us to provide a quantitative account of the experimental neutron scattering data within a consistent quantum spin model. Moreover, we trace the details of the continuous evolution of the amplitude mode from a two-particle bound state of coupled ladders in the classical Ising limit all the way to the quantum spin-1/2 Heisenberg limit with fully restored SU(2) symmetry, where it gets overdamped by the two-magnon continuum in neutron scattering.

Improvement of quality of life and mental health in patients with spasmodic torticollis after microvascular decompression

OBJECTIVE

Although not life threatening, spasmodic torticollis (ST) impairs patients' daily activity, socialization and work. The aim of this study was to evaluate the quality of life (QOL) and mental health in patients with ST after microvascular decompression (MVD).

PATIENTS AND METHODS

From June 2014 to June 2017, patients with ST who underwent MVD in our department were included in this study. Toronto Western Sparse Torticollis Rating Scale (TWSTRS) were used to evaluate the ST symptoms. Quality of life was assessed by the craniocervical dystonia questionnaire (CDQ-24). Beck Depression Inventory (BDI-II) and Beck Anxiety Inventory (BAI) were used to evaluate the mental health. Intraoperative findings and follow-up results were analyzed.

RESULTS

A total of 104 consecutive patients were enrolled in this study. At the 12 months follow-up, the total effective rate was 81.73%. After MVD surgery, 88(84.62%) ST patients experienced QOL improvement. The severity of ST symptoms was positively correlated with the CDQ-24 score(r = 0.31, P = 0.02). Forty-eight patients (46.16%) with ST have moderate to severe depression and nine (8.65%) have depression preoperatively. Pain and disability domains of TWSTRS were found have high relation with BDI-II score(r = 0.27, P = 0.02; r = 0.33, P = 0.03). There was a positive correlation of educational levels with the BDI-II scores(r = 0.45, P = 0.02).

CONCLUSION

ST affects patients' QOL both physically and mentally. MVD for ST not only provides high spasm-relief rate but also leads to significantly higher QOL after surgery. Not only ST symptoms, but also psychiatric status of patients should be routinely followed. Psychological care and psychopharmaceuticals should also be considered for these patients.

Occurrences of online fraud complaints: 2002 through 2015

Purpose

The purpose of this paper is to report on the findings and lessons that were learned from the many cases of internet fraud complaints that are gathered by the Federal Trade Commission in the USA. The implications that are contained in the behavior of the complaints and trends identified are critical for addressing all types of online criminal activities in the increasing world of cybercrimes.

Design/methodology/approach

Data for this paper are extracted from the Consumer Sentinel Network Data Handbook covering a period of 13 years. Using the raw data, the occurrences were plotted and trends (number of cycles, time between cycles, and leading state and lagging states) were identified. Descriptive statistics covering the 13 years were examined and discussed. Using 20002 as the base year, the rate of growth of each of the states were ranked annually and were tested for stability and predictability using non-parametric approaches.

Findings

The key findings are indigenous to the occurrences of online fraud complaints in the USA. However, as the leading nation with the best database on fraud complaints, the findings are mission critical to fraud prevention across the globe. Specifically, this study found that since 2002, there have been four distinct cycles. Each cycle is clearly noticeable because there is a rapid growth in the number of crime complaints in the beginning half of the period followed by a slowing down period. However, the speed of change from one cycle to the next is steeper and the time gap is faster. While it is true that from the perspective of all the 50 states, the ranks appear to change every year and thus are not stable. However, the majority of the changes are relatively small so their relative positions by rank are still predictable.

Originality/value

The paper extends existing understanding of online fraud occurrences in the USA. The findings are timely and based on longitudinal data that span over a decade. The four new cycles identified are critical to the body of knowledge. The observed change in time from one cycle to another and its changes from a mathematic to a geometric one are also new. The findings are invaluable to persons working in law enforcement related occupations (auditors, lawyers, forensic experts, among others) and who must deal with the increasing problem of online fraud and cybercrimes.

MicroRNA-137 and its downstream target LSD1 inversely regulate anesthetics-induced neurotoxicity in dorsal root ganglion neurons

PURPOSE

Anesthetic reagents, such as bupivacaine (Bv), induce significant neurotoxicity in dorsal root ganglion neurons (DRGNs). In this study, we investigated the expression, function and cross-association of microRNA-137-3p (miR-137-3p) and lysine (K)-specific demethylase 1A (LSD1) in a murine model of Bv-induced neural injury in DRGNs.

METHODS

Murine DRGNs were culture in vitro and treated with Bv. QPCR was used to evaluate miR-137-3p expression in Bv-injured DRGNs. MiR-137-3p was genetically downregulated to evaluate its rescuing effect on Bv-induced DRGN apoptosis and neurite retraction. The association of miR-137-3p on its downstream target, LSD1 coding gene KDM1A, was evaluated by dual-luciferase activity assay and qPCR. In miR-137-3p-downregulated DRGNs, KDM1A was inhibited to evaluate its involvement in miR-137-3p-mediated modulation on Bv-induced DRGN neurotoxicity. Furthermore, KDM1A expression in Bv-injured DRGN was evaluated by qPCR, and LSD1 was overexpressed in DRGN to evaluate its direct effect on Bv-induced neurotoxicity.

RESULTS

MiR-137-3p was upregulated in Bv-injured DRGNs. MiR-137-3p downregulation rescued Bv-induced DRGN apoptosis and neurite retraction. LSD1 was demonstrated to be downstream to, and inversely modulated by miR-137-3p in DRGN. In Bv-injured DRGNs, LSD1 downregulation reversed miR-137-3p-downregualtion-induced neural protection. Furthermore, LSD1 upregulation directly rescued Bv-induced apoptosis and neurite retraction in DRGNs.

CONCLUSIONS

MiR-137-3p and its downstream target LSD1 are inversely associated to regulate anesthetics-induced neurotoxicity in DRGN. This signaling pathway may be a therapeutic candidate to reduce anesthetics-induced neurological damage in human patients.

Management of different kinds of veins during microvascular decompression for trigeminal neuralgia: technique notes

OBJECTIVE

During microvascular decompression surgery for trigeminal neuralgia, surgeons will encounter various kinds of veins that block the approach to or compress the trigeminal nerve. The aim of this study was to present our experience in managing different kinds of veins.

METHODS

This was a retrospective study of 21 patients with trigeminal neuralgia, in whom one or more veins were encountered during surgery. The techniques used in treating 4 types of veins during microvascular decompression were assessed, and the surgical outcomes and operative complications were analysed.

RESULTS

For the first type, large veins blocking the approach towards the root entry zone (REZ) of the trigeminal nerve were bypassed via cerebellar fissure approach. Second, veins lying on the brainstem surface and compressing the REZ were detached using a gelatin-assisted dissecting technique and then interposed. Third, veins rising from the surface of the brainstem and crossing the cisternal portion of the trigeminal nerve were interposed. Fourth, intraneural veins, which were generally small, were coagulated and cut. In this series, there was no intentional sacrifice or unintentional rupture of large veins, and the sacrifice rate of medium and small veins was only 19.0%. Thirteen patients (61.9%) gained complete pain relief immediately after surgery (i.e. "excellent" result), while the remaining eight patients (38.1%) achieved "good" pain relief.

CONCLUSION

Different surgical techniques were used based on the different kinds of veins encountered. This allowed preservation of almost all the large veins. There were no serious complications postoperatively.

The Incidence of Early Postoperative Conductive Hearing Loss after Microvascular Decompression of Hemifacial Spasm

Objectives To evaluate the incidence and discuss the pathogenesis of early postoperative conductive hearing loss (CHL) after microvascular decompression (MVD) for hemifacial spasm (HFS). Design Pre- and postoperative audiogram data and brainstem auditory evoked potentials (BAEPs) from patients who had underwent MVD for HFS were analyzed. Setting The study was conducted at the University of Pittsburgh Medical Center. Participants MVD for HFS patients who had pre- and postoperative audiogram data, BAEP data, and normal structure of the external and middle ear were included in the study. Main Outcome Measures CHL was diagnosed if there was an air-bone gap in pure tone audiometry of at least 10 dB at 0.5, 1, 2, or 4 kHz. Results The incidence of early postoperative CHL in the ipsilateral ear was 18.7% postoperatively. No CHL was observed in the contralateral side. No significant relationship between CHL and intraoperative BAEP changes was found. Demographic parameters were not significantly different between groups with and without CHL. Conclusions Early postoperative CHL is a significant complication after MVD. Fluid entering the mastoid air cells and/or bone-dust deposition during craniotomy may result in CHL. Long-term audiograms will be needed to evaluate the risk factors that lead to permanent CHL.

Combined intraoperative monitoring of abnormal muscle response and Z-L response for hemifacial spasm with tandem compression type

BACKGROUND

Multiple neurovascular compression is present in about 38 % cases of hemifacial spasm (HFS). In these cases, the vertebral artery (VA) compresses another vessel, which in turn compresses the nerve. This type was named as "the tandem type". In the tandem type, the real offending vessel is often concealed by the VA. It is sometimes neglected by the surgeons. In this study, we report our experience in using abnormal muscle response (AMR) and ZL-Response (ZLR) simultaneously as intraoperative monitoring for MVD surgery of HFS with "the tandem type" vascular compression involving VA.

METHODS

Fourteen "tandem type" patients treated with microvascular decompression surgery (MVD) surgery were included. ZLR and AMR were recorded simultaneously to identify the offending vessels in operation.

RESULTS

After MVD surgery, 13 patients achieved excellent resolution of spasm. In one case, the patient failed to attain resolution in the first operation, underwent early reoperation and had good resolution. There were no operative deaths or serious operative complications. In all 14 cases, we found that VA compressed the anterior inferior cerebellar artery (AICA) or posterior inferior cerebellar artery (PICA), which in turn compressed the root exit zone (REZ). A typical ZLR was identified from the AICA or PICA but not from the VA. AMR was absent in one case and persisted in one case. After the VA was transposed, the typical AMR was unchanged, unstable or disappeared, and ZLR from the AICA/PICA also existed. AMR and ZLR did not disappear until AICA/PICA was sufficiently decompressed.

CONCLUSIONS

The combination of AMR and ZLR provides more useful information than does the AMR alone, and ZLR may be the only useful intraoperative monitoring for MVD surgery in times when AMR is absent or persists. ZLR played a crucial role in finding the real offending vessel, which was often concealed by the VA in tandem type.

Emprical factors associated with Brainstem auditory evoked potential monitoring during microvascular decompression for hemifacial spasm and its correlation to hearing loss

BACKGROUND

Cranial nerve VIII is at risk during microvascular decompression (MVD) for hemifacial spasm (HFS). The primary aim of this study is to evaluate the empirical factors associated with brainstem auditory evoked potential monitoring and its correlation to post operative hearing loss (HL) after MVD for HFS.

METHODS

Pre-operative and post-operative audiogram data and BAEP from ninety-four patients who underwent MVD for HFS were analyzed. Pure tone audiometry (PTA) and Speech Discrimination Score (SDS) were performed on all patients before and after surgery. Intraoperative neurophysiological data were reviewed independently. HL was assessed using the AAO-HNS classification system for non-serviceable hearing loss (Class C/D), defined as PTA >50 dB and/or SDS <50% within the speech range of frequencies.

RESULTS

Patients with HL had higher rates of loss in the amplitude of wave V and prolongation in the interpeak latency of peak I-V latency during MVD. Gender, age, side, and MVD duration did not increase the risk of HL. There was no correlation between successive number of BAEP changes (reflective of the number of surgical attempts) and HL. There was no association between the speed of recovery of BAEPs and HL.

CONCLUSIONS

Patients with new post-operative HL have a faster rate of change in the amplitude of wave V and the interpeak I-V latency during intraoperative BAEP monitoring for HFS. Our alarm criteria to inform the surgeon about impending nerve injury might have to be modified and prospectively tested to prevent rapid change in BAEPs.

Surgical treatment of hemifacial spasm with zone-4 offending vessel

BACKGROUND

Increasing evidence shows that vascular compression on any of the four zones of facial nerve may cause hemifacial spasms. Vascular compression on zone 4 (the cisternal portion) of the nerve is quite common, but only a very small percentage of such compression will elicit hemifacial spasm, because zone 4 is less susceptible than zone 3 (the root exit zone). Therefore, it seems difficult for the neurosurgeons to distinguish the real culprit vessels in zone 4. Here, our experience in treating vascular compression located in zone 4 of the facial nerve is reported.

METHODS

Twelve patients of HFS due to compression of zone 4 were treated with microvascular decompression (MVD) surgery with the aid of combined monitoring of abnormal muscle response (AMR) and Z-L response (ZLR).

RESULTS

All of the 12 patients had a zone 4 compression. In addition, there were vascular compressions on zone 3 (the root exit zone) and/or zone 2 (the attached segment) in six cases. AMR was absent in two cases, unstable in one case, and persisted after vascular decompression in another one case. ZLR was stable before decompression of zone 4 and disappeared after decompression in all cases. After MVD surgery, 11 patients were cured and one patient achieved good resolution of spasm. One patient had postoperative transient tinnitus.

CONCLUSIONS

The neurosurgeon should not ignore vascular compression at zone 4, especially when compressions at zones 2 and 3 co-exist. With the aid of AMR and ZLR, we are able to judge whether offending vessels exist at zone 4.

Incidence of high-frequency hearing loss after microvascular decompression for hemifacial spasm

OBJECT

The primary aim of this study was to evaluate the incidence and discuss the pathogenesis of high-frequency hearing loss (HFHL) after microvascular decompression (MVD) for hemifacial spasm (HFS).

METHODS

Preoperative and postoperative audiogram data and brainstem auditory evoked potentials (BAEPs) from 94 patients who underwent MVD for HFS were analyzed. Pure tone audiometry at 0.25-2 kHz, 4 kHz, and 8 kHz was calculated for all individuals pre- and postoperatively ipsilateral and contralaterally. Intraoperative neurophysiological data were reviewed independently. An HFHL was defined as a change in pure tone audiometry of more than 10 dB at frequencies of 4 and 8 kHz.

RESULTS

The incidence of HFHL was 50.00% and 25.53% ipsilateral and contralateral to the side of surgery, respectively. The incidence of HFHL adjusted for conductive and nonserviceable hearing loss was 26.6% ipsilaterally. The incidence of HFHL at 4 and 8 kHz on the ipsilateral side was 37.23% and 45.74%, respectively, and it was 10.64% and 25.53%, respectively, on the contralateral side. Maximal change in interpeak latency Waves I-V compared with baseline was the only variable significantly different between groups (p < 0.05). Sex, age, and side did not increase the risk of HFHL. Stepwise logistic regression analysis did not find any changes in intraoperative BAEPs to increase the risk of HFHL.

CONCLUSIONS

High-frequency hearing loss occurs in a significant number of patients following MVD surgery for HFS. Drill-induced noise and transient loss of CSF during surgery may impair hearing in the high-frequency ranges on both the ipsilateral and contralateral sides, with the ipsilateral side being more affected. Changes in intraoperative BAEPs during MVD for HFS were not useful in predicting HFHL. Follow-up studies and repeat audiological examinations may be helpful in evaluating the time course and prognosis of HFHL. Prospective studies focusing on decreasing intraoperative noise exposure, as well as auditory shielding devices, will establish causation and allow the team to intervene appropriately to decrease the risk of HFHL.

Surgical treatment of pediatric hemifacial spasm patients

PURPOSE

To study the clinical features and outcomes of pediatric primary hemifacial spasm patients who underwent microvascular decompression procedures.

METHODS

In this retrospective study, five pediatric (<18 years old) primary hemifacial spasm patients underwent microvascular decompression. After surgery, resolution of spasms and surgical complications were observed. Their social adaptability was evaluated using a social adaptation scale, which was designed specially for Chinese middle-school students.

RESULTS

Four typical hemifacial spasm patients had immediate excellent or good relief. However, the microvascular decompression procedure did not help the atypical patient much (50% relief of spasm). The score of social adaptation of the pediatric hemifacial spasm patients was 111.6  ±  8.2. Compared with the ordinary healthy Chinese middle-school students, whose score is 170.8  ±  25.4, the patients experienced great difficulty in social adaptation (P  <  0.01). After surgery, the scores of two patients increased to a normal level; however, the other three patients remained unchanged.

CONCLUSIONS

Microvascular decompression is effective and safe to typical primary hemifacial spasm patients younger than 18 years old. Hemifacial spasm is harmful to the children's social adaptation. However, only some of the patients recovered to the normal social adaptation level even when the spasms were cured.

Analysis of the ethylene response in the epinastic mutant of tomato

Ethylene can alter plant morphology due to its effect on cell expansion. The most widely documented example of ethylene-mediated cell expansion is promotion of the "triple response" of seedlings grown in the dark in ethylene. Roots and hypocotyls become shorter and thickened compared with controls due to a reorientation of cell expansion, and curvature of the apical hook is more pronounced. The epinastic (epi) mutant of tomato (Lycopersicon esculentum) has a dark-grown seedling phenotype similar to the triple response even in the absence of ethylene. In addition, in adult plants both the leaves and the petioles display epinastic curvature and there is constitutive expression of an ethylene-inducible chitinase gene. However, petal senescence and abscission and fruit ripening are all normal in epi. A double mutant (epi/epi;Nr/Nr) homozygous for both the recessive epi and dominant ethylene-insensitive Never-ripe loci has the same dark-grown seedling and vegetative phenotypes as epi but possesses the senescence and ripening characteristics of Never-ripe. These data suggest that a subset of ethylene responses controlling vegetative growth and development may be constitutively activated in epi. In addition, the epi locus has been placed on the tomato RFLP map on the long arm of chromosome 4 and does not demonstrate linkage to reported tomato CTR1 homologs.