Multiple HAPS-based space-air-ground network with FSO communication: a performance analysis.

Due to the fact that the existing generation of wireless communication cannot possibly keep up with the current traffic explosion and emerging applications, research and development on next-generation (i.e., sixth generation, 6G) wireless technologies is being carried out worldwide. In this regard, it is anticipated that the space-air-ground (SAG) network with free space optics (FSO) communication can provide the terabits per second throughput necessary to sustain various potential 6G applications. However, FSO communications are susceptible to atmospheric turbulence, pointing errors, and beam scintillation effects. To remedy the severe atmospheric effects, we propose a multiple high-altitude platform station (HAPS)-based SAG network with a HAPS selection scheme. For the proposed system, we have derived the closed-form expressions for outage probability, average symbol error rate (SER), ergodic capacity, and outage capacity over Málaga distribution with pointing errors. Further, the asymptotic expressions for outage probability, average SER, and outage capacity were derived to enhance the comprehension of the system from a practical standpoint. It is observed from the numerical results that the multiple HAPS-based FSO system performs better than the existing HAPS-based FSO systems.

Multihop IRS-assisted free space optics communication with DF relaying: a performance analysis.

Free space optics communication (FSO) offers several advantages over its counterpart radio frequency (RF) systems in terms of bandwidth, data rates, and cost efficiency. However, FSO, being a line-of-sight (LoS) communication system, is hindered by various environmental factors. In this paper, we propose a multihop decode-and-forward (DF) relaying-based intelligent reflecting surface (IRS)-assisted FSO system with an aim to deal with the impediments in FSO communication, and it is assumed that each IRS consists of multiple reflecting elements. Specifically, we derive end-to-end expressions for cumulative distribution function (CDF) of output instantaneous signal-to-noise ratio (SNR). Furthermore, with the aid of the CDF statistics, we study the performance of the proposed system by obtaining the expressions for outage probability (OP) and average symbol error rate (ASER) in terms of multivariate Fox's H-function. Moreover, we have quantified the system performance by numerical results. The numerical results show that the multihop IRS-assisted FSO system provides better performance when compared to a single-hop IRS-assisted FSO system and multihop FSO system without IRS. Finally, the derived expressions of OP and ASER are validated using Monte-Carlo simulations.

Intelligent-reflecting-surfaces-assisted hybrid FSO/RF communication with diversity combining: a performance analysis.

Free space optics (FSO) and radio frequency (RF) communication systems exhibit complementary characteristics, with FSO being susceptible to fog, turbulence, and pointing errors, whereas RF is susceptible to rain and small scale fading. These inherent complementary characteristics between FSO and RF communication systems enable the hybrid configuration to effectively alleviate the impact of environmental impediments. This paper presents the performance analysis of an intelligent reflecting surfaces (IRSs)-assisted hybrid FSO/RF system under atmospheric turbulence (AT), pointing errors (PE), small scale fading effects, and attenuation due to climatic conditions such as fog, rain, etc. To characterize the AT, gamma-gamma distribution is used, and the multipath fading in the RF link is modeled using Nakagami-m distribution. At the receiver, signals from both the FSO and RF links are combined using either the selection combining (SC) or maximal-ratio combining (MRC) technique. We derive the exact closed-form expressions for outage probability and average symbol error rate (ASER) for both diversity combining schemes. The proposed system is compared with the direct link (DL) FSO system, IRSs-assisted FSO system, and hybrid FSO/RF system with diversity combining schemes. Further, the performance comparison between the SC and MRC schemes is also reported. Finally, the accuracy of the analytical expressions is verified by utilizing Monte Carlo simulations.

MeCP2-regulated miRNAs control early human neurogenesis through differential effects on ERK and AKT signaling.

Rett syndrome (RTT) is an X-linked, neurodevelopmental disorder caused primarily by mutations in the methyl-CpG-binding protein 2 (MECP2) gene, which encodes a multifunctional epigenetic regulator with known links to a wide spectrum of neuropsychiatric disorders. Although postnatal functions of MeCP2 have been thoroughly investigated, its role in prenatal brain development remains poorly understood. Given the well-established importance of microRNAs (miRNAs) in neurogenesis, we employed isogenic human RTT patient-derived induced pluripotent stem cell (iPSC) and MeCP2 short hairpin RNA knockdown approaches to identify novel MeCP2-regulated miRNAs enriched during early human neuronal development. Focusing on the most dysregulated miRNAs, we found miR-199 and miR-214 to be increased during early brain development and to differentially regulate extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase and protein kinase B (PKB/AKT) signaling. In parallel, we characterized the effects on human neurogenesis and neuronal differentiation brought about by MeCP2 deficiency using both monolayer and three-dimensional (cerebral organoid) patient-derived and MeCP2-deficient neuronal culture models. Inhibiting miR-199 or miR-214 expression in iPSC-derived neural progenitors deficient in MeCP2 restored AKT and ERK activation, respectively, and ameliorated the observed alterations in neuronal differentiation. Moreover, overexpression of miR-199 or miR-214 in the wild-type mouse embryonic brains was sufficient to disturb neurogenesis and neuronal migration in a similar manner to Mecp2 knockdown. Taken together, our data support a novel miRNA-mediated pathway downstream of MeCP2 that influences neurogenesis via interactions with central molecular hubs linked to autism spectrum disorders.

Comparison of nested-multiplex, Taqman & SYBR Green real-time PCR in diagnosis of amoebic liver abscess in a tertiary health care institute in India.

BACKGROUND & OBJECTIVES: Amoebiasis is a common parasitic infection caused by Entamoeba histolytica and amoebic liver abscess (ALA) is the most common extraintestinal manifestation of amoebiasis. The aim of this study was to standardise real-time PCR assays (Taqman and SYBR Green) to detect E. histolytica from liver abscess pus and stool samples and compare its results with nested-multiplex PCR. METHODS: Liver abscess pus specimens were subjected to DNA extraction. The extracted DNA samples were subjected to amplification by nested-multiplex PCR, Taqman (18S rRNA) and SYBR Green real-time PCR (16S-like rRNA assays to detect E. histolytica/E. dispar/E. moshkovskii). The amplification products were further confirmed by DNA sequence analysis. Receiver operator characteristic (ROC) curve analysis was done for nested-multiplex and SYBR Green real-time PCR and the area under the curve was calculated for evaluating the accuracy of the tests to dignose ALA. RESULTS: In all, 17, 19 and 25 liver abscess samples were positive for E. histolytica by nested-multiplex PCR, SYBR Green and Taqman real-time PCR assays, respectively. Significant differences in detection of E. histolytica were noted in the real-time PCR assays evaluated ( P<0.0001). The nested-multiplex PCR, SYBR Green real-time PCR and Taqman real-time PCR evaluated showed a positivity rate of 34, 38 and 50 per cent, respectively. Based on ROC curve analysis (considering Taqman real-time PCR as the gold standard), it was observed that SYBR Green real-time PCR was better than conventional nested-multiplex PCR for the diagnosis of ALA. INTERPRETATION & CONCLUSIONS: Taqman real-time PCR targeting the 18S rRNA had the highest positivity rate evaluated in this study. Both nested multiplex and SYBR Green real-time PCR assays utilized were evaluated to give accurate results. Real-time PCR assays can be used as the gold standard in rapid and reliable diagnosis, and appropriate management of amoebiasis, replacing the conventional molecular methods.

Cancer Incidence in Five Continents: Inclusion criteria, highlights from Volume X and the global status of cancer registration.

Cancer Incidence in Five Continents (CI5), a longstanding collaboration between the International Agency for Research on Cancer and the International Association of Cancer Registries, serves as a unique source of cancer incidence data from high-quality population-based cancer registries around the world. The recent publication of Volume X comprises cancer incidence data from 290 registries covering 424 populations in 68 countries for the registration period 2003-2007. In this article, we assess the status of population-based cancer registries worldwide, describe the techniques used in CI5 to evaluate their quality and highlight the notable variation in the incidence rates of selected cancers contained within Volume X of CI5. We also discuss the Global Initiative for Cancer Registry Development as an international partnership that aims to reduce the disparities in availability of cancer incidence data for cancer control action, particularly in economically transitioning countries, already experiencing a rapid rise in the number of cancer patients annually.

Efficacy of Turmeric as Adjuvant Therapy in Type 2 Diabetic Patients.

It is known that there is a significant interplay of insulin resistance, oxidative stress, dyslipidemia, and inflammation in type 2 diabetes mellitus (T2DM). The study was undertaken to investigate the effect of turmeric as an adjuvant to anti-diabetic therapy. Sixty diabetic subjects on metformin therapy were recruited and randomized into two groups (30 each). Group I received standard metformin treatment while group II was on standard metformin therapy with turmeric (2 g) supplements for 4 weeks. The biochemical parameters were assessed at the time of recruitment for study and after 4 weeks of treatment. Turmeric supplementation in metformin treated type 2 diabetic patient significantly decreased fasting glucose (95 ± 11.4 mg/dl, P < 0.001) and HbA1c levels (7.4 ± 0.9 %, P < 0.05). Turmeric administered group showed reduction in lipid peroxidation, MDA (0.51 ± 0.11 µmol/l, P < 0.05) and enhanced total antioxidant status (511 ± 70 µmol/l, P < 0.05). Turmeric also exhibited beneficial effects on dyslipidemia LDL cholesterol (113.2 ± 15.3 mg/dl, P < 0.01), non HDL cholesterol (138.3 ± 12.1 mg/dl, P < 0.05) and LDL/HDL ratio (3.01 ± 0.61, P < 0.01) and reduced inflammatory marker, hsCRP (3.4 ± 2.0 mg/dl, P < 0.05). Turmeric supplementation as an adjuvant to T2DM on metformin treatment had a beneficial effect on blood glucose, oxidative stress and inflammation.

C-H Oxidation of Ingenanes Enables Potent and Selective Protein Kinase C Isoform Activation.

Ingenol derivatives with varying degrees of oxidation were prepared by two-phase terpene synthesis. This strategy has allowed access to analogues that cannot be prepared by semisynthesis from natural ingenol. Complex ingenanes resulting from divergent C-H oxidation of a common intermediate were found to interact with protein kinase C in a manner that correlates well with the oxidation state of the ingenane core. Even though previous work on ingenanes has suggested a strong correlation between potential to activate PKCδ and induction of neutrophil oxidative burst, the current study shows that the potential to activate PKCßII is of key importance while interaction with PKCδ is dispensable. Thus, key modifications of the ingenane core allowed PKC isoform selectivity wherein PKCδ-driven activation of keratinocytes is strongly reduced or even absent while PKCßII-driven activation of neutrophils is retained.

Laparoscopic kidney transplant by extra peritoneal approach: the safe transition from laboratory to the clinic.

The aim of this study is to develop a novel laparoscopic surgery by extra-peritoneal approach for kidney transplant and pave the way of safe transition from laboratory to the clinic. The study was established to explore the feasibility and safety of human laparoscopic kidney transplant. The experiment was first conducted on the deceased animals, then live animals and human cavader before human kidney transplant was approved. The study patient was a 49-year-old male who received the kidney for laparoscopic kidney transplant by extra-peritoneal approach. The control patient received the contralateral kidney for open kidney transplant. The estimated blood loss was minimal during surgery. Both kidneys experienced delayed graft function but the kidneys started function on Day 6 postoperation. The analgesia consumption was significantly less in the study patient. There is no surgical complication during 6-month follow-up. This study has developed a new technique for laparoscopic kidney transplant by extra-peritoneal approach. It has retained the advantages of open kidney transplant, which allows the graft located in the extra-peritoneal space without violating peritoneum. This study has also paved the way of safe transition for a novel laparoscopic surgery from laboratory to the clinic.

Record of Natula matsuurai Sugimoto (Orthoptera: Gryllidae: Trigonidiinae) and other sword-tailed crickets from India.

The genus Natula is a new record from the state of Rajasthan, India. Description of the species has been supported with photographs and line drawings leading to its identification. The other common sword-tailed crickets of the sub-family Trigonidiinae have also been described.

A systematic review on efficacy, safety and cost-effectiveness of office-based laryngeal biopsy.

OBJECTIVE: Laryngeal cancer is the second most prevalent head and neck malignancy in the USA. With recent advances in technology, this procedure is increasingly performed under local anaesthesia. This study aimed to identify the efficacy, safety and cost-effectiveness of laryngeal biopsy in out-patients by conducting a systematic review. METHOD: A literature search was conducted using PubMed, Medline, Google Scholar and Embase over a 20-year period. Inclusion criteria were: studies performed on out-patient diagnostic biopsy procedures of the larynx. Exclusion criteria included all therapeutic procedures. The outcome measures were sensitivity and specificity, complication rate and cost-savings. RESULTS: Thirty-five studies were included in the analysis. The sensitivity and specificity varied from 60 to 100 per cent with a low complication rate and cost savings. CONCLUSION: Office-based laryngeal biopsies are increasingly used in the diagnosis of laryngeal cancers, resulting in earlier diagnosis and commencement of treatment. The barrier to undertaking this procedure is low sensitivity.

Dynamics of oral human papillomavirus infection in healthy population and head and neck cancer.

The recent increase in high-risk human papillomavirus (HR-HPV)-associated oral and oropharyngeal cancers has gained considerable importance due to their distinct clinical and molecular characteristics. However, the natural history of oral HPV from acquisition to persistence and malignant transformation is still unclear. The global prevalence of oral HPV infection in healthy individuals ranges from 0.67% to 35%, while 31%-38.5% in head and neck cancer (HNC). The persistence rate of oral HR-HPV infection is 5.5% -12.8% globally. India has the highest HNC burden due to apparent differences in predisposing factors compared with the West. The prevalence of oral HPV in healthy individuals and its contribution to HNC is less evident in Indian studies. HR-HPV-associated HNC in this region accounts for 26%, with an active infection in 8%-15% of these tumors. There is a lack of concordance in the expression of p16 as a surrogate marker for HPV detection in HNC because of differences in behavioral risk factors. Due to a lack of evidence, treatment de-escalation cannot be implemented despite the improved outcome of HPV-associated oropharyngeal cancers. This review critically analyzes the existing literature on the dynamics of oral HPV infection and HPV-associated HNC, identifying potential avenues for future research. A better understanding of the oncogenic role of HR-HPV in HNC will help to formulate novel therapeutic approaches and is expected to have a significant public health impact as preventive strategies can be implemented.

Assessment of Registry-Based Surveillance Statistics Used for Cancer Control in the Dindigul District in South India.

Background: Cancer incidence rates from the Dindigul district were lower by 50% than Chennai in Tamil Nadu for most cancers. This study describes the cancer surveillance statistics and provides an assessment of missing cases from routine registration in the Dindigul Ambilikkai Cancer Registry (DACR), covering a predominantly rural population in the Dindigul district. Method: A total of 21,214 incident cancers in the DACR during 2003-2017 were examined for this study. Cancer registration was carried out by active case-finding following standard international norms. A total of 12,541 incident cancers registered during 2003-2012 and followed through 2014 were used to estimate survival. Data on follow-up were obtained through a mixture of active and passive methods. Survival probability was estimated by actuarial methods. A random survey carried out independently was used to assess the quality of case ascertainment. Results: The age-standardized rate (ASR) per 100,000 population was higher among women (76.2) than men (61) in 2013-2017, with both sexes reporting a 17% increase compared to 2003-2007. The most common cancers were cervix (ASR,18.5) and female breast (ASR,17.1), with percentage changes of -19% and +46.1%, respectively. Lung cancer (ASR, 5.5) was top among men with an increasing trend (+57.1%). The percent change in ASR of mouth cancer showed opposite trends among men (+24.3%) and women (- 21.4%). The ASR of colorectal cancers almost doubled among men between 2003-2007 and 2013-2017 (3.9; +94.7%). The 5- and 10-year absolute survival for all cancers were 31% and 20%, respectively. Out of 365 incident cancers that occurred during 2003-2010 in the surveyed areas, 310 (84.9%) were already registered in the DACR, while 55 were newly identified from the survey (15.1%). Inadequate coverage of sources outside the Dindigul district was significant (P = .002), with the highest number of missed cases from hospitals under nongovernment sectors (58.3%). Underascertainment was higher among cancer patients living in hilly regions (60%) and border areas (47.4%) than in core regions (P = .05). Conclusion: Because of an enacted government order making cancer a notifiable disease, the registry-based cancer surveillance could be extended, covering a population of 80 million in a cost-effective manner with enhanced coverage and systematic evaluation of cancer-screening programs.

An assessment of childhood cancer care services in India - gaps, challenges and the way forward.

Background: Childhood cancers are emerging as an essential concern in India where there is lack of a specific programme component or policy to address childhood cancer control. There is limited information on the status and quality of childhood cancer care services in India. This paper describes the childhood cancer care services available at secondary and tertiary-level hospitals in India through a cross sectional study design. Methods: The survey was conducted in 137 tertiary-level and 92 secondary-level hospitals in 26 states and 4 Union Territories (UTs), ensuring a uniform representation of public and private care hospitals. The study tool collected data on the organisational infrastructure, type of oncology services, health workforce, equipment, treatment and referral protocols, and treatment guidelines. Descriptive statistics was used to primarily present the health service status and data on childhood cancer care services in proportions and mean. Findings: A dedicated pediatric oncology department was available in 41.6% of the public, 48.6% of private, and 64% Non Government Organization (NGO) managed tertiary-level hospitals. In 36 (39%) of the 92 hospitals providing secondary care, childhood cancer care was provided. The availability of bone (41.5%) and positron emission tomography (PET) scans (25.9%) was lower in public tertiary hospitals, whereas histopathology, computerised tomography (CT scan), and magnetic resonance imaging (MRI) were lower in public secondary hospitals than private and NGO managed hospitals for the corresponding level of care. Most tertiary hospitals had the required supportive care facilities except for play therapy and hospice care. Less than 50% of the public tertiary hospitals had stocks of the four categories of cancer-treating drugs and essential infrastructure for radiotherapy and chemotherapy. Most secondary-level hospitals not treating childhood cancer had referral linkages with tertiary hospitals. Interpretation: The situational analysis of childhood cancer care services in India showed the concentration of availability of childhood cancer care services at the tertiary level of health care. There were gaps in the availability of specialised pediatric oncology care in all the tertiary hospitals. The availability of childhood cancer care services was higher in private and NGO-managed hospitals than in public hospitals. Integration of childhood cancer as a part of the national cancer control response should be taken up as a matter of priority. The need of the hour is to formulate a childhood cancer policy that will enable timely access to care universally. Funding: World Health Organization, India provided funding and technical support.

Weight in infancy and adult calcium absorption as determinants of bone mineral density in adult men: the Hertfordshire cohort study.

Adult bone mass is modified by early life environmental influences, but the mechanism of this association is uncertain. Data support an inverse relationship between intestinal calcium absorption (αCa) and birth weight in women. However, little is known regarding determinants in men. This study examines the association between weight in infancy and adult αCa in healthy men and whether this could be a mechanism by which the early life environment may influence bone mass. Men were recruited from the MRC Hertfordshire Cohort Study, for whom detailed early life records were available. Areal bone mineral density (aBMD) was measured using a Hologic QDR 4500 at the femoral neck (FN) and lumbar spine. We randomly selected 123 men stratified by birth weight and assessed αCa using the stable strontium absorption test. The mean age was 63.6 (SD 2.5) years. αCa was not associated with birth weight or weight at 1 year. FN aBMD was associated with both weight at 1 year (r = 0.20, p = 0.03) and αCa (r = 0.20, p = 0.03). Both of these associations remained statistically significant in a mutually adjusted, multivariable model but would account for only ~4 % variance in BMD. We demonstrated a positive association between weight at 1 year and aBMD and between αCa and FN BMD, but no association was found between birth weight and αCa. This suggests that in men, although αCa is a contributing factor in FN bone density, it is not the main mechanism whereby the early environment modifies adult BMD.

Synthesis and biological activity of pyridopyridazin-6-one p38α MAP kinase inhibitors. Part 2.

This manuscript concludes the Structure Activity Relationship (SAR) on the pyridazinone scaffold and identifies a compound with subnanomolar p38α activity and 24h coverage in the rat arthritis efficacy model.

Visual improvement following continuous positive airway pressure therapy in diabetic subjects with clinically significant macular oedema and obstructive sleep apnoea: proof of principle study.

BACKGROUND: Diabetic retinopathy and diabetic macular oedema are more prevalent in patients with coexistent obstructive sleep apnoea (OSA). OBJECTIVES: We assessed if treatment of OSA with continuous positive airway pressure (CPAP) might improve visual acuity (VA). METHODS: A total of 35 patients with clinically significant macular oedema (CSMO) and OSA [oxygen desaturation index (ODI) ≥10 or apnoea-hypopnoea index (AHI) ≥15] were identified and agreed to be studied. VA (expressed as the logarithm of the minimum angle of resolution, logMAR), macular thickness, fundal photographs, glycosylated haemoglobin (HbA1c) and rhodopsin mRNA were measured twice at baseline and at 3 and 6 months post-CPAP. Fluorescein angiography and the Epworth Sleepiness Scale (ESS) were obtained once at baseline and at 6 months. RESULTS: Three patients withdrew before the first trial visit. Thus, a total of 32 patients (17 males) entered the study, and 4 subsequently withdrew; thus 28 completed 6 months of follow-up. Baseline characteristics of the subjects were as follows [mean (SD or inter-quartile range)]: age 66.2 (7.1) years, body mass index 31.7 (6.3), HbA1c 7.4% (1.44) [57.1 (15.7) mmol/mol], AHI 16.5 (11-25), ODI 16.0 (12-25), ESS 6.5 (4.0-12.0) and duration of diabetes 9.5 years (5.0-16.5). Participants were divided into 13 high and 15 low CPAP compliers (≥ and <2.5 h/night over the 6 months, respectively). At 6 months, the adjusted treatment effect on VA of high compliance versus low compliance was 0.11 (95% confidence interval 0.21 to -0.002; p = 0.047), equivalent to a one-line improvement on the logMAR chart. There was no significant improvement in macular oedema or fundal photographs. CONCLUSIONS: This hypothesis-generating, uncontrolled study suggests that ≥2.5 h/night CPAP usage over 6 months in individuals with CSMO and OSA may be associated with improvement in VA. This provides justification for a randomised controlled trial of CPAP therapy in such patients.

Reperfusion therapy in ST-elevation myocardial infarction: guidelines, strategies, pharmacology, and stent selection.

Treatment of acute ST-elevation myocardial infarction (STEMI) has rapidly evolved with many advances made in the past decade. Percutaneous coronary intervention is the preferred strategy when available, although there remains a role for thrombolytic therapy, with prompt reperfusion as the primary goal. With regards to antithrombotic therapy, bivalirudin now has a significant role in STEMI care with improved outcomes over unfractionated heparin plus GP IIb/IIIa inhibitors. Dual antiplatelet therapy has become a mainstay of treatment with combination of aspirin and clopidogrel, as well as an expanding role of more potent novel agents, prasugrel and ticagrelor. In primary PCI in STEMI, coronary stents are now being used routinely, although short-term and long-term outcomes of drug-eluting stents (DES) versus bare metal stents (BMS) continue to be studied. Recent meta-analyses have examined the trade-off of lower rates of in-stent restenosis and need for target vessel revascularization with DES versus the potential increase in the risk of stent thrombosis and need for longer course of dual antiplatelet therapy. This review will discuss the current STEMI guidelines and strategies, recent advances in pharmacotherapy, and data on stent selection.

Retrospective analysis of the risk of neoplasia associated with unilateral maxillary sinus opacification on computed tomography.

BACKGROUND: Unilateral maxillary sinus opacification on computed tomography may reflect an inflammatory or neoplastic process. The neoplasia risk is not clear in the literature. METHODS: In this retrospective study, computed tomography sinus scans performed over 12 months were screened for unilateral maxillary sinus opacification, and the rates of inflammatory and neoplastic diagnoses were calculated. RESULTS: Of 641 computed tomography sinus scans, the rate of unilateral maxillary sinus opacification was 9 per cent. Fifty-two cases were analysed. The risk of neoplasia was 2 per cent (inverted papilloma, n = 1). No cases of unilateral maxillary sinus opacification represented malignancy, but one case of lymphoma had an incidental finding of unilateral maxillary sinus opacification on the contralateral side. Patients with an antrochoanal polyp (n = 3), fungal disease (n = 1), inverted papilloma and lymphoma all had a unilateral nasal mass. CONCLUSION: Our neoplasia rate of 2 per cent was lower than previously reported. A unilateral mass was predictive of pathology that required operative management. Clinical findings, rather than simple findings of opacification on computed tomography, should drive the decision to perform biopsy.

Magnetic resonance imaging of the internal auditory meatus for vestibular schwannoma in ENT practice: a retrospective analysis with literature and guidelines review.

OBJECTIVES: Magnetic resonance imaging scans of the internal acoustic meatus are commonly requested in the investigation of audio-vestibular symptoms for potential vestibular schwannoma. There have been multiple studies into protocols for requesting magnetic resonance imaging for vestibular schwannoma, but none have been reported based on UK National Institute for Health and Care Excellence guidelines for investigating audio-vestibular symptoms. This study intended to identify the local magnetic resonance imaging detection rates and patterns of vestibular schwannoma, and to audit the conformity of scan requests with the National Institute for Health and Care Excellence guidelines, with a review of relevant literature. METHOD: A retrospective analysis of 1300 magnetic resonance imaging scans of the internal acoustic meatus, compared against National Institute for Health and Care Excellence guidelines, was conducted over two years. RESULTS AND CONCLUSION: Sixteen scans were positive for vestibular schwannoma, with a detection rate of 1.23 per cent. All positive cases fit the guidelines; three of these could have been missed using other criteria. A total of 281 requests did not meet the guideline criteria but revealed no positive results, supporting the use of National Institute for Health and Care Excellence guidelines in planning magnetic resonance imaging scans for audio-vestibular symptoms.