Solitary sclerotic fibroma of the palpebral conjunctiva: a unique presentation of a rare entity.

Sclerotic fibroma (SF) is an uncommon yet benign tumor that may occasionally be associated with Cowden's disease that presents as an asymptomatic, well-circumscribed lesion. We present a rare case of a patient with a solitary SF of the palpebral conjunctiva. The patient was an 85-year-old male who presented with a right lower lid nodule that was initially treated as a chalazion. Excision yielded a dense mass that was sent to pathology for evaluation. Histologically, the lesion showed a bland storiform spindle cell proliferation embedded in a sclerotic stroma with prominent clefting.

Artificial Intelligence Automation of Proptosis Measurement: An Indicator for Pediatric Orbital Abscess Surgery.

INTRODUCTION: To evaluate the ability of artificial intelligence (AI) software to quantify proptosis for identifying patients who need surgical drainage. METHODS: We pursued a retrospective study including 56 subjects with a clinical diagnosis of subperiosteal orbital abscess (SPOA) secondary to sinusitis at a tertiary pediatric hospital from 2002 to 2016. AI computer software was developed to perform 3D visualization and quantitative assessment of proptosis from computed tomography (CT) images acquired at the time of hospital admission. The AI software automatically computed linear and volume metrics of proptosis to provide more practice-consistent and informative measures. Two experienced physicians independently measured proptosis using the interzygomatic line method on axial CT images. The AI software and physician proptosis assessments were evaluated for association with eventual treatment procedures as standalone markers and in combination with the standard predictors. RESULTS: To treat the SPOA, 31 of 56 (55%) children underwent surgical intervention, including 18 early surgeries (performed within 24 h of admission), and 25 (45%) were managed medically. The physician measurements of proptosis were strongly correlated (Spearman r = 0.89, 95% CI 0.82-0.93) with 95% limits of agreement of ± 1.8 mm. The AI linear measurement was on average 1.2 mm larger (p = 0.007) and only moderately correlated with the average physicians' measurements (r = 0.53, 95% CI 0.31-0.69). Increased proptosis of both AI volumetric and linear measurements were moderately predictive of surgery (AUCs of 0.79, 95% CI 0.68-0.91, and 0.78, 95% CI 0.65-0.90, respectively) with the average physician measurement being poorly to fairly predictive (AUC of 0.70, 95% CI 0.56-0.84). The AI proptosis measures were also significantly greater in the early as compared to the late surgery groups (p = 0.02, and p = 0.04, respectively). The surgical and medical groups showed a substantial difference in the abscess volume (p < 0.001). CONCLUSION: AI proptosis measures significantly differed from physician assessments and showed a good overall ability to predict the eventual treatment. The volumetric AI proptosis measurement significantly improved the ability to predict the likelihood of surgery compared to abscess volume alone. Further studies are needed to better characterize and incorporate the AI proptosis measurements for assisting in clinical decision-making.

OCT Angiography in Noninfectious Uveitis: A Description of Five Cases and Clinical Applications.

BACKGROUND: Optical coherence tomography angiography (OCTA) is a noninvasive imaging modality used to analyze the retinochoroidal vasculature and detect vascular flow. The resulting images can be segmented to view each vascular plexus individually. While fluorescein angiography is still the gold standard for the diagnosis of posterior uveitis, it has limitations, and can be replaced by OCTA in some cases. METHODS: This case series describes five patients with posterior noninfectious uveitis and their description by OCTA. RESULTS: Cases included lupus retinopathy (n = 1) for which OCTA showed ischemic maculopathy as areas of flow deficit at the superficial and deep capillary plexus; choroidal granulomas (n = 1) with a non-detectable flow signal in the choroid; active punctate inner choroiditis and multifocal choroiditis (n = 1) with OCTA that showed active inflammatory chorioretinal lesions as non-detectable flow signals in choriocapillaris and choroid; dense type 2 inflammatory secondary neovascularization (n = 1) associated with active choroiditis; and acute posterior multifocal placoid pigment epitheliopathy (APMPPE) (n = 1) without flow abnormalities at the superficial and deep retinal plexuses but non-detectable flow at the levels of the choriocapillaris and choroid. CONCLUSIONS: Ophthalmologists can use OCTA to identify inflammatory changes in retinal and choroidal vasculature, aiding in the diagnosis, management, and monitoring of posterior uveitis.

More than just a stye: identifying seasonal patterns using google trends, and a review of infodemiological literature in ophthalmology.

PURPOSE: We aim to evaluate the utility of internet search query data in ophthalmology by: (1) Evaluating trends in searches for styes in the United States and worldwide, and (2) Performing a review of literature of infodemiological data in ophthalmology. METHODS: Google Trends search data for "stye" was analyzed from January 2004 to January 2020 in the United States and worldwide. Spearman's correlation coefficient and sinusoidal modeling were performed to assess the significance and seasonality of trends. Review of literature included searches for "ophthalmology Google trends," "ophthalmology twitter trends," "ophthalmology infodemiology," "eye google trends," and "social media ophthalmology." RESULTS: Searches for styes were cyclical in the United States and globally with a steady increase from 2004 to 2020 (sum-of-squares F-test for sinusoidal model: p < .0001, r2 = 0.96). Peak search volume index (SVI) months were 7.9 months in the United States and 6.8 months worldwide. U.S. temperature and SVI for stye were correlated in the United States at the state, divisional, and country-wide levels (p < .005; p < .005; p < .01 respectively). Seven articles met our literature review inclusion criteria. CONCLUSIONS: We present a novel finding of seasonality with global and U.S. searches for stye, and association of searches with temperature in the United States. Within ophthalmology, infodemiological literature has been used to track trends and identify seasonal disease patterns, perform disease surveillance, improve resource optimization by identifying regional hotspots, tailor marketing, and monitor institutional reputation. Future research into this domain may help identify further trends, improve prevention efforts, and reduce medical costs.

Utility of diffusion-weighted imaging to differentiate benign and malignant solid orbital tumours.

OBJECTIVE: We assessed the utility of apparent diffusion coefficients (ADCs) derived from diffusion-weighted imaging to differentiate benign and malignant orbital tumours by oculoplastic surgeons in the clinical setting and sought to validate observed ADC cut-off values. DESIGN AND PARTICIPANTS: Retrospective review of patients with benign or malignant biopsy-confirmed orbital tumours. METHODS: Blinded graders including 2 oculoplastic surgeons, 1 neuroradiologist, and 1 medical student located and measured orbital tumour ADCs (10-6 mm2/s) using the Region of Interest tool. OUTCOME MEASURES: Nonradiologist measurements were compared with each other to assess reliability and with an expert neuroradiologist measurement and final pathology to assess accuracy. RESULTS: Twenty-nine orbital tumours met inclusion criteria, consisting of 6 benign tumours and 23 malignant tumours. Mean ADC values for benign orbital tumours were 1430.59 ± 254.81 and 798.68 ± 309.12 mm2/s for malignant tumours. Our calculated optimized ADC cut-off to differentiate benign from malignant orbital tumours was 1120.84 × 10-6 mm2/s (sensitivity 1, specificity 0.9). Inter-rater reliability was excellent (intraclass correlation coefficient = 0.92; 95% CI, 0.86-0.96). Our 3 graders had a combined accuracy of 84.5% (92.3%, 92.3%, and 65.4%). CONCLUSIONS: Our ADC cut-off of 1120.84 × 10-6 mm2/s for benign and malignant orbital tumours agrees with previously established values in literature. Without priming with instructions, training, or access to patient characteristics, most tumours were correctly classified using rapid ADC measurements. Surgeons without radiologic expertise can use the ADC tool to quickly risk stratify orbital tumours during clinic visits to guide patient expectations and further work-up.

Contralateral Forced Eyelid Closure Increases Intraocular Pressure.

OBJECTIVES: The purpose of the study was to describe the influence of contralateral forced eyelid closure on intraocular pressure (IOP). METHODS: Twenty-one healthy volunteers with no ophthalmic history had their IOP measured in the supine position to simulate the intraoperative environment. Intraocular pressure was measured with a handheld tonometer over three scenarios: (1) both eyes in a relaxed state, (2) eyelid speculum in the right eye with both eyes open and relaxed, (3) eyelid speculum in the right eye with the fellow eye squeezing tightly. RESULTS: Intraocular pressure significantly increased with forced contralateral eyelid squeezing compared with the relaxed state by a mean of 7.71±5.08 mm Hg (95% Confidence Interval of 5.40-7.37), P<0.001. CONCLUSIONS: Contralateral eyelid squeezing can significantly increase intraoperative IOP measurements.

The clinical presentation and magnetic resonance imaging characteristics of an infant with idiopathic orbital inflammation.

Idiopathic orbital inflammation is rare in the pediatric population, particularly infants. It can be mistaken either for orbital infection or malignant tumors. We report the case of a 9-month-old previously healthy white boy who presented with right upper eyelid swelling. Magnetic resonance imaging revealed an abnormal T2-hypointense enhancing lesion within the extraconal superior right orbit.

The impact of cochlear implantation on speech and language outcomes in children with asymmetric sensorineural hearing loss.

INTRODUCTION: Cochlear implantation (CI) is considered in children with asymmetric sensorineural hearing loss (ASHL), or severe to profound sensorineural hearing loss in one ear, and better hearing contralaterally. The benefits of a CI in these children are not well established. This study investigated the impact of unilateral CI on speech and language outcomes in pediatric patients with ASHL. METHODS: The retrospective chart review identified pediatric patients who underwent cochlear implantation for ASHL at a tertiary single center institution between 2014 and 2017. Children who underwent cochlear implantation in the poorer ear and maintained a hearing aid in the better ear were included, while children with cognitive impairment or prior cochlear nerve deficiency and auditory neuropathy were excluded. Speech and language measures were evaluated prior to implantation and at regular six-month intervals postoperatively. Ear specific Audiometry was evaluated at every visit and varied developmentally appropriate speech recognition tasks, including questionnaires, closed-set, and open-set measures, accounted for advancing childhood milestones. Specific measures of speech articulation, expressive and receptive language, and vocabulary were assessed including: Goldman Fristoe Test of Articulation (GFTA-3), Clinical Evaluation of Language Fundamentals (CELF-P2 or CELF-5), Receptive One-Word Picture Vocabulary Test (ROWPVT) and Expressive One Word Picture Vocabulary Test (EOWPVT). The mean difference and standard deviation of speech and language outcomes at preoperative and postoperative evaluations were calculated. The change in outcomes were further assessed over each post-operative time point. RESULTS: Twenty-six children with asymmetric sensorineural hearing loss were included in the analysis, with 11 (42%) having bilateral enlarged vestibular aqueducts (EVA). At time of CI, unaided mean Pure Tone Average (PTA-4) for the better ear was 62Db HL, and worse ear was 92Db HL. There was an improvement in speech recognition in the implanted ear as expected. All preoperative speech and language evaluations were conducted within 7 months of cochlear implantation. Twenty-three patients had at least 1 postoperative re-evaluation. Fourteen children had preoperative and postoperative assessments with the same tool, with 13 patients (93%) showing improvement in at least 1 domain. For patients with repeated assessment within 12 months of surgery, we observed an average improvement in standard scores of: GFTA-3 (+11.2), CELF-P2 Core Language (+10.3), CELF-5 Core Language (+7.0), ROWPVT (+2.8) and EOWPVT (+4.5). Individual results are described. CONCLUSION: Improvement in speech and language measures can be demonstrated in children undergoing unilateral cochlear implantation for asymmetric sensorineural hearing losses. These children, who are not typical CI candidates, can benefit from a CI in the poorer ear.

The incidence of stroke post neck dissection surgery and perioperative management.

BACKGROUND: Head and neck surgery encompasses major vessels, raising the concern of life-threatening complications such as stroke. METHODS: Databases at UPMC were queried to identify patients with both neck dissections and stroke from January 1st, 2004, to October 1st, 2020. A retrospective chart review was performed to identify patients who experienced a stroke within 30 days of a neck dissection. RESULTS: Search of a UPMC database for carotid artery stenosis (CAS), transient ischemic attack (TIA), and stroke identified 20,527 patients. After matching with the Head and Neck Tumor Registry patients, 41 of 4230 patients with a neck dissection also had a stroke, TIA, or CAS in their lifetime. One patient, with multiple risk factors, despite pre-operative precautions, had a stroke 2 days post neck dissection in the setting of carotid occlusion from hypercoagulability of malignancy and intraoperative vessel injury. The patient subsequently underwent a carotid thrombectomy and vein patch repair and has had no additional cerebrovascular accidents. CONCLUSION: Although the incidence of stroke post neck dissection is minimal, patients with multiple risk factors for stroke should be managed carefully to prevent deleterious outcomes.

Optimal "Low" Pedicle Screw Stimulation Threshold to Predict New Postoperative Lower-Extremity Neurologic Deficits During Lumbar Spinal Fusions.

OBJECTIVE: Previous studies have shown that pedicle screw stimulation thresholds ≤6-8 mA yield a high diagnostic accuracy of detecting misplaced screws. Our objective was to determine the optimal "low" stimulation threshold to predict new postoperative neurologic deficits and identify additional risk factors associated with deficits. METHODS: We included patients with complete pedicle screw stimulation testing who underwent posterior lumbar spinal fusion surgeries from 2010-2012. We calculated the diagnostic accuracy of pedicle screw responses of ≤4 mA, ≤6 mA, ≤8 mA, ≤10 mA, ≤12 mA, and ≤20 mA to predict new postoperative lower-extremity (LE) neurologic deficits. We used multivariate modeling to determine the best logistic regression model to predict LE deficits and identify additional risk factors. Statistics software packages used were Python3.8.5, NumPy 1.19.1, Pandas 1.1.1, and SPSS26. RESULTS: We studied 1179 patients who underwent 8584 pedicle screw stimulations with somatosensory evoked potential and free-run electromyographic monitoring for posterior lumbar spinal fusion. Twenty-five (2.1%) patients had new LE neurologic deficits. A stimulation threshold of ≤8 mA had a sensitivity/specificity of 32%/90% and a diagnostic odds ratio/area under the curve of 4.34 [95% confidence interval: 1.83, 10.27]/0.61 [0.49, 0.74] in predicting postoperative deficit. Multivariate analysis showed that patients who had pedicle screws with stimulation thresholds ≤8 mA are 3.15 [1.26, 7.83]× more likely to have postoperative LE deficits while patients who have undergone a revision lumbar spinal fusion surgery are 3.64 [1.38, 9.61]× more likely. CONCLUSIONS: Our results show that low thresholds are indicative of not only screw proximity to the nerve but also an increased likelihood of postoperative neurologic deficit. Thresholds ≤8 mA prove to be the optimal "low" threshold to help guide a correctly positioned pedicle screw placement and detect postoperative deficits.

Trends in Anti-VEGF Injection Medicare Part B Claims among Male and Female Ophthalmologists from 2012-2016.

Background: Compared to male ophthalmologists, female ophthalmologists have significantly reduced salaries, fewer faculty roles and authored publications, garnered less federal research funding, and achieved less editorial advancement. We aimed to use the most recently available Centers for Medicare and Medicaid Services data to characterize trends and differences in anti-VEGF reimbursements coded for by male and female ophthalmologists.Methods: We used Medicare Fee-For Service Provider Utilization and Payment Data: Part B Provider public use files for 2012-2016 to quantify service and reimbursement patterns for anti-VEGF injections between male and female ophthalmologists. Five outcome variables were studied: number of providers, average Medicare payment amount, total payment, number of services, and number of Medicare beneficiaries.Results: Number of services performed per female provider was 71.2% that of a male ophthalmologist in 2012, and this percentage did not change from 2012 to 2016 (95%CI [0.63, 0.804], [0.984, 1.04], respectively). Female providers had 76.1% of beneficiaries as males in 2012, and this percentage stayed constant throughout the years (95%CI [0.69, 0.84] and [0.99, 1.03], respectively). The total payment difference between female and males was $102,175 per provider in 2012, and this gap widened by $18,292 yearly (95% CI [-162599.17, -41760.47], [-33060.35, -3524.38], respectively).Conclusion: While male and female providers saw considerable increases in aflibercept services and payments in the 5-year period, the gap between male and female reimbursements widened significantly. Moving forward, analysis of large-scale Medicare datasets provides a tangible report card on how effective our attitudes and policies are in cultivating equal opportunity.

Diagnostic Accuracy of Thresholds Less Than or Equal to 8 mA in Pedicle Screw Testing During Lumbar Spine Procedures to Predict New Postoperative Lower Extremity Neurological Deficits.

STUDY DESIGN: Retrospective observational study. OBJECTIVE: It has been shown that pedicle screw stimulation thresholds less than or equal to 8 mA yield a very high diagnostic accuracy of detecting misplaced screws in spinal surgery. In our study, we determined clinical implications of low stimulation thresholds. SUMMARY OF BACKGROUND DATA: Posterior lumbar spinal fusions (PSF), using pedicle screws, are performed to treat many spinal pathologies, but misplaced pedicle screws can result in new postoperative neurological deficits. METHODS: Patients with pedicle screw stimulation testing who underwent PSF between 2010 and 2012 at the University of Pittsburgh Medical Center (UPMC) were included in the study. We evaluated the sensitivity, specificity, and diagnostic odds ratio (DOR) to determine how effectively low pedicle screw responses predict new postoperative lower extremity neurological deficits. RESULTS: One thousand one hundred seventy nine eligible patients underwent 8584 pedicle screw stimulations with lower extremity somatosensory evoked potentials (LE SSEP) monitoring for lumbar fusion surgery. One hundred twenty one of these patients had 187 pedicle screws with a stimulation response at a threshold less than or equal to 8 mA. Smoking had a significant correlation to pedicle screw stimulation less than or equal to 8 mA (P = 0.012). A threshold of less than or equal to 8 mA had a sensitivity/specificity of 0.32/0.90 with DOR of 4.34 [1.83, 10.27] and an area under the ROC curve (AUC) of 0.61 [0.49, 0.74]. Patients with screw thresholds less than or equal to 8 mA and abnormal baselines had a DOR of 9.8 [95% CI: 2.13-45.17] and an AUC of 0.73 [95% CI: 0.50-0.95]. CONCLUSION: Patients with pedicle screw stimulation thresholds less than or equal to 8 mA are 4.34 times more likely to have neurological clinical manifestations. Smoking and LE deficits were shown to be significantly correlated with pedicle screw stimulation thresholds less than or equal to 8 mA. Low stimulation thresholds result in a high specificity of 90%. Pedicle screw stimulation less than or equal to 8 mA can serve as an accurate rule in test for postoperative neurological deficit, warranting reevaluation of screw placement and/or replacement intraoperatively.Level of Evidence: 3.

Variations in Surgical Outcomes of Carotid Body Tumors by Surgical Specialty.

OBJECTIVES/HYPOTHESIS: A carotid body tumor (CBT) is a rare type of tumor that is divided among multiple surgical specialties. Individual surgeons may have limited experience in treating these tumors. We aim to compare different surgical specialties within a single healthcare system to detect variations in management and outcome. STUDY DESIGN: Retrospective chart review. METHODS: A chart review of all patients who underwent surgery for CBT at the University of Pittsburgh Medical Center (UPMC) from 2000 to 2019 was carried out. Univariate and multivariate analysis was used for descriptive statistics, comparison of outcomes, and identification of risk factors. RESULTS: Fifty-eight CBT resection surgeries were performed at UPMC. Patients with advanced tumor were 6.7 (95% confidence interval [CI]: 1.36-32.7) times more likely to undergo preoperative embolization and 8.53 (95% CI: 2.011-36.19) times more likely to sustain carotid artery injury. Advanced-stage tumor resections were associated with greater blood loss (P = .03) and longer hospitalization (P = .02). Collaborative surgeries were associated with higher rates of carotid artery injury (P = .003), residual tumor (P < .001), and longer hospitalization (P = .003), as these combined cases were generally reserved for advanced-stage tumors (P = .02). There were no differences in outcomes between specialties. Of 22 surgeons, the median number of surgeries per surgeon was one (range = 1-12, 54.5%). CONCLUSIONS: Surgeons who completed only one surgery for CBT had a greater rate of hospital readmission and greater length of hospital stay. Collaborative surgeries had worse outcomes due to more advanced tumors requiring more complex surgeries. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E190-E195, 2021.

The efficacy of somatosensory evoked potentials in evaluating new neurological deficits after spinal thoracic fusion and decompression.

OBJECTIVE: Posterior thoracic fusion (PTF) is used as a surgical treatment for a wide range of pathologies. The monitoring of somatosensory evoked potentials (SSEPs) is used to detect and prevent injury during many neurological surgeries. The authors conducted a study to evaluate the efficacy of SSEPs in predicting perioperative lower-extremity (LE) neurological deficits during spinal thoracic fusion surgery. METHODS: The authors included patients who underwent PTF with SSEP monitoring performed throughout the entire surgery from 2010 to 2015 at the University of Pittsburgh Medical Center (UPMC). The sensitivity, specificity, odds ratio, and receiver operating characteristic curve were calculated to evaluate the diagnostic accuracy of SSEP changes in predicting postoperative deficits. Univariate analysis was completed to determine the impact of age exceeding 65 years, sex, obesity, abnormal baseline testing, surgery type, and neurological deficits on the development of intraoperative changes. RESULTS: From 2010 to 2015, 771 eligible patients underwent SSEP monitoring during PTF at UPMC. Univariate and linear regression analyses showed that LE SSEP changes significantly predicted LE neurological deficits. Significant changes in LE SSEPs had a sensitivity and specificity of 19% and 96%, respectively, in predicting LE neurological deficits. The diagnostic odds ratio for patients with new LE neurological deficits who had significant changes in LE SSEPs was 5.86 (95% CI 2.74-12.5). However, the results showed that a loss of LE waveforms had a poor predictive value for perioperative LE deficits (diagnostic OR 1.58 [95% CI 0.19-12.83]). CONCLUSIONS: Patients with new postoperative LE neurological deficits are 5.9 times more likely to have significant changes in LE SSEPs during PTF. Surgeon awareness of an LE SSEP loss may alter surgical strategy and positively impact rates of postoperative LE neurological deficit status. The relatively poor sensitivity of LE SSEP monitoring may indicate a need for multimodal neurophysiological monitoring, including motor evoked potentials, in thoracic fusion surgery.

The diagnostic accuracy of somatosensory evoked potentials in evaluating neurological deficits during 1057 lumbar interbody fusions.

BACKGROUND: Lumbar interbody spinal fusion (LIF) surgeries are performed to treat or prevent back pain in patients with degenerated intervertebral discs and a variety of spinal diseases. However, post-operative neurological complications may ensue. Intraoperative monitoring techniques have been used to predict and potentially reduce the risk of complications. METHODS: This study examined the diagnostic accuracy of significant changes of somatosensory evoked potentials (SSEPs) to evaluate and predict post-operative neurological deficits after LIF. All patients underwent LIF at UPMC from 2010 to 2012. One thousand fifty-seven patients had pre-operative baseline and continuous intraoperative SSEP monitoring. Statistical analysis was completed using SPSS version 22. No relevant disclosure. RESULTS: Patient outcomes were not significantly affected by age over 65, gender, obesity, and abnormal baselines. Lower extremity (LE) significant changes in SSEPs and LE loss of responses resulted in a sensitivity/specificity of 0.03/0.99 and 0.03/0.99; they had an AUC of 0.54/0.73 with a 95% confidence interval (CI) of [0.34, 0.74]/[0.29, 1.00]. CONCLUSIONS: Significant SSEP changes during LIF are a very specific but poorly sensitive indicator of perioperative neurological deficits. The odds ratio for LE loss of responses was 29.14 with a 95% CI of 1.79-475.5, so LE SSEP loss of responses can serve as a biomarker of perioperative neurological deficits after LIF.

Risk factors for positioning-related somatosensory evoked potential changes in 3946 spinal surgeries.

The goal of this study was to evaluate the risk factors associated with positioning-related SSEP changes (PRSC). The study investigated the association between 18 plausible risk factors and the occurrence of intraoperative PRSC. Risk factors investigated included demographic variables, comorbidities, and procedure related variables. All patients were treated by the University of Pittsburgh Medical Center from 2010 to 2012. We used univariate and multivariate statistical methods. 69 out of the 3946 (1.75%) spinal surgeries resulted in PRSC changes. The risk of PRSC was increased for women (p < 0.001), patients older than 65 years of age (p = 0.01), higher BMI (p < 0.001) patients, smokers (p < 0.001), and patients with hypertension (p < 0.001). No associations were found between PRSC and age greater than 80 years, diabetes mellitus, cardiovascular disease, and peripheral vascular disease. Three surgical situations were associated with PRSC including abnormal baselines (p < 0.001), patients in the "superman" position (p < 0.001), and patients in surgical procedures that extended over 200 min (p = 0.03). Patients with higher BMIs and who are undergoing spinal surgery longer than 200 min, with abnormal baselines, must be positioned with meticulous attention. Gender, hypertension, and smoking were also found to be risk factors from their odds ratios.