Patient Travel Distance to Neurologist Visits.

BACKGROUND AND OBJECTIVES: The density of neurologists within a given geographic region varies greatly across the United States. We aimed to measure patient travel distance and travel time to neurologist visits, across neurologic conditions and subspecialties. Our secondary goal was to identify factors associated with long-distance travel for neurologic care. METHODS: We performed a cross-sectional analysis using a 2018 Medicare sample of patients with at least 1 outpatient neurologist visit. Long-distance travel was defined as driving distance ≥50 miles 1-way to the visit. Travel time was measured as driving time in minutes. Multilevel generalized linear mixed models with logistic link function, which accounted for clustering of patients within hospital referral region and allowed modeling of region-specific random effects, were used to determine the association of patient and regional characteristics with long-distance travel. RESULTS: We identified 563,216 Medicare beneficiaries with a neurologist visit in 2018. Of them, 96,213 (17%) traveled long distance for care. The median driving distance and time were 81.3 (interquartile range [IQR]: 59.9-144.2) miles and 90 (IQR: 69-149) minutes for patients with long-distance travel compared with 13.2 (IQR: 6.5-23) miles and 22 (IQR: 14-33) minutes for patients without long-distance travel. Comparing across neurologic conditions, long-distance travel was most common for nervous system cancer care (39.6%), amyotrophic lateral sclerosis [ALS] (32.1%), and MS (22.8%). Many factors were associated with long-distance travel, most notably low neurologist density (first quintile: OR 3.04 [95% CI 2.41-3.83] vs fifth quintile), rural setting (4.89 [4.79-4.99]), long-distance travel to primary care physician visit (3.6 [3.51-3.69]), and visits for ALS and nervous system cancer care (3.41 [3.14-3.69] and 5.27 [4.72-5.89], respectively). Nearly one-third of patients bypassed the nearest neurologist by 20+ miles, and 7.3% of patients crossed state lines for neurologist care. DISCUSSION: We found that nearly 1 in 5 Medicare beneficiaries who saw a neurologist traveled ≥50 miles 1-way for care, and travel burden was most common for lower-prevalence neurologic conditions that required coordinated multidisciplinary care. Important potentially addressable predictors of long-distance travel were low neurologist density and rural location, suggesting interventions to improve access to care such as telemedicine or neurologic subspecialist support to local neurologists. Future work should evaluate differences in clinical outcomes between patients with long-distance travel and those without.

Levonorgestrel intrauterine device use and incident idiopathic intracranial hypertension among commercially insured women.

OBJECTIVES: To estimate the hazard of incident idiopathic intracranial hypertension, a potentially blinding condition, among women using levonorgestrel intrauterine devices (LNG-IUD) compared to copper IUD, as conflicting associations have been reported. STUDY DESIGN: This retrospective, longitudinal cohort study identified women ages 18-45 years in a large care network (January 1, 2001, to December 31, 2015) using LNG-IUD, subcutaneous etonogestrel implant, copper IUD, tubal device/surgery, or hysterectomy. Incident idiopathic intracranial hypertension was defined as the first diagnosis code for after 1 year without any codes and following brain imaging or lumbar puncture. Kaplan-Meier analysis estimated time-dependent probabilities of idiopathic intracranial hypertension at 1 and 5 years after incident contraception use, stratified by type. Cox regression estimated the hazard of idiopathic intracranial hypertension associated with LNG-IUD use compared to copper IUD (primary comparison) after adjusting for sociodemographics and factors associated with idiopathic intracranial hypertension (e.g., obesity) or contraception selection. A sensitivity analysis with propensity score-adjusted models was performed. RESULTS: Of 268,280 women, 78,175 (29%) used LNG-IUD, 8715 (3%) etonogestrel implant, 20,275 (8%) copper IUD, 108,216 (40%) hysterectomy, 52,899 (20%) tubal device/surgery, and 208 (0.08%) developed idiopathic intracranial hypertension over a mean follow-up of 2.4 ± 2.4 years. Also, 1-/5-year Kaplan-Meier idiopathic intracranial hypertension probabilities were 0.0004/0.0021 for LNG-IUD and 0.0005/0.0006 for copper IUD users. LNG-IUD use did not show significantly different hazard of idiopathic intracranial hypertension compared to copper IUD (adjusted hazard ratio 1.84 [95% CI 0.88, 3.85]). Sensitivity analyses were similar. CONCLUSIONS: We did not observe a significantly increased hazard of idiopathic intracranial hypertension among women using LNG-IUD compared to copper IUDs. IMPLICATIONS: The lack of an association between LNG-IUD use and idiopathic intracranial hypertension in this large observational study provides reassurance to women considering initiation or continued use of this highly effective contraceptive method.

A Validated Method to Identify Neuro-Ophthalmologists in a Large Administrative Claims Database.

BACKGROUND: Validated methods to identify neuro-ophthalmologists in administrative data do not exist. The development of such method will facilitate research on the quality of neuro-ophthalmic care and health care utilization for patients with neuro-ophthalmic conditions in the United States. METHODS: Using nationally representative, 20% sample from Medicare carrier files from 2018, we identified all neurologists and ophthalmologists billing at least 1 office-based evaluation and management (E/M) outpatient visit claim in 2018. To isolate neuro-ophthalmologists, the National Provider Identifier numbers of neuro-ophthalmologists in the North American Neuro-Ophthalmology Society (NANOS) directory were collected and linked to Medicare files. The proportion of E/M visits with International Classification of Diseases-10 diagnosis codes that best distinguished neuro-ophthalmic care ("neuro-ophthalmology-specific codes" or NSC) was calculated for each physician. Multiple logistic regression models assessed predictors of neuro-ophthalmology specialty designation after accounting for proportion of ophthalmology, neurology, and NSC claims and primary specialty designation. Sensitivity, specificity, and positive predictive value (PPV) for varying proportions of E/M visits with NSC were calculated. RESULTS: We identified 32,293 neurologists and ophthalmologists who billed at least 1 outpatient E/M visit claim in 2018 in Medicare. Of the 472 NANOS members with a valid individual National Provider Identifier, 399 (84.5%) had a Medicare outpatient E/M visit in 2018. The model containing only the proportion of E/M visits with NSC best predicted neuro-ophthalmology specialty designation (odds ratio 1.05 [95% confidence interval 1.04, 1.05]; P < 0.001; area under the receiver operating characteristic [AUROC] = 0.91). Model predictiveness for neuro-ophthalmology designation was maximized when 6% of all billed claims were for NSC (AUROC = 0.89; sensitivity: 84.0%; specificity: 93.9%), but PPV was low (14.9%). The threshold was unchanged when limited only to neurologists billing ≥1% ophthalmology claims or ophthalmologists billing ≥1% neurology claims, but PPV increased (33.3%). CONCLUSIONS: Our study provides a validated method to identify neuro-ophthalmologists who can be further adapted for use in other administrative databases to facilitate future research of neuro-ophthalmic care delivery in the United States.

Validity of International Classification of Diseases Codes for Identifying Neuro-Ophthalmic Disease in Large Data Sets: A Systematic Review.

BACKGROUND: Administrative health claims data have been used for research in neuro-ophthalmology, but the validity of International Classification of Diseases (ICD) codes for identifying neuro-ophthalmic conditions is unclear. EVIDENCE ACQUISITION: We performed a systematic literature review to assess the validity of administrative claims data for identifying patients with neuro-ophthalmic disorders. Two reviewers independently reviewed all eligible full-length articles and used a standardized abstraction form to identify ICD code-based definitions for 9 neuro-ophthalmic conditions and their sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). A quality assessment of eligible studies was also performed. RESULTS: Eleven articles that met criteria for inclusion are as follows: 3 studies of idiopathic intracranial hypertension (PPV 54%-91% and NPV 74%-85%), 2 studies of giant cell arteritis (sensitivity 30%-96% and PPV 94%), 3 studies of optic neuritis (sensitivity 76%-99%, specificity 83%-100%, PPV 25%-100%, and NPV 98%-100%), 1 study of neuromyelitis optica (sensitivity 60%, specificity 100%, PPV 43%-100%, and NPV 98%-100%), 1 study of ocular motor cranial neuropathies (PPV 98%-99%), and 2 studies of myasthenia gravis (sensitivity 53%-97%, specificity 99%-100%, PPV 5%-90%, and NPV 100%). No studies met eligibility criteria for nonarteritic ischemic optic neuropathy, thyroid eye disease, and blepharospasm. Approximately 45.5% provided only one measure of diagnostic accuracy. Complete information about the validation cohorts, inclusion/exclusion criteria, data collection methods, and expertise of those reviewing charts for diagnostic accuracy was missing in 90.9%, 72.7%, 81.8%, and 36.4% of studies, respectively. CONCLUSIONS: Few studies have reported the validity of ICD codes for neuro-ophthalmic conditions. The range of diagnostic accuracy for some disorders and study quality varied widely. This should be taken into consideration when interpreting studies of neuro-ophthalmic conditions using administrative claims data.

Rapid visual field constriction in a patient with retinitis pigmentosa and pituitary adenoma.

PURPOSE: To report a case of pituitary adenoma in a patient with retinitis pigmentosa (RP) and consequent rapid constriction of the visual field in each eye, which is atypical for either of these pathologies. OBSERVATIONS: A 45-year old male, with a long-standing history of RP, presented with rapid vision loss over 3 months. Examination revealed a severe drop in visual acuity and significant progression of concentric visual field constriction in each eye compared to 3 months prior. MRI revealed a pituitary macroadenoma compressing the optic chiasm. The patient underwent endoscopic trans-sphenoidal resection of the tumor and experienced partial recovery of visual acuity but not visual field. CONCLUSIONS AND IMPORTANCE: The visual field deficit in this patient was atypical for pituitary adenoma or optic neuropathy. The pattern was most consistent with RP, but the rate of progression was not. In a patient with chiasmal pathology in the setting of pre-existing retinopathy, visual field progression may not be limited exclusively to the bitemporal regions. Rapid constriction of the visual field in a patient with RP should prompt a work-up for alternative etiologies which includes neuro-imaging.

Multiple sclerosis relapse risk in the postoperative period: Effects of invasive surgery and anesthesia.

BACKGROUND: Postoperative multiple sclerosis (MS) relapses are a concern among patients and providers. OBJECTIVE: To determine whether MS relapse risk is higher postoperatively. METHODS: Data were extracted from medical records of MS patients undergoing surgery at a tertiary center (2000-2016). Conditional logistic regression estimated within-patient unadjusted and age-adjusted odds of postoperative versus preoperative relapse. RESULTS: Among 281 patients and 609 surgeries, 12 postoperative relapses were identified. The odds of postoperative versus preoperative relapse in unadjusted (odds ratio (OR) = 0.56, 95% confidence interval (CI) = 0.18-1.79; p = 0.33) or age-adjusted models (OR = 0.66, 95% CI = 0.20-2.16; p = 0.49) were not increased. CONCLUSIONS: Surgery/anesthesia exposure did not increase postoperative relapse risk. These findings require confirmation in larger studies.

Causes of Horner Syndrome: A Study of 318 Patients.

BACKGROUND: Some reports have indicated that when a cause for Horner syndrome can be determined, it is most often chest and neck tumors and stroke. Others have suggested that Horner syndrome is more frequently caused by surgical procedures in the neck and chest. These differences may be explained by disparate accrual methods. Therefore, we decided to compare the cause of Horner syndrome in cases where the diagnosis was confirmed by apraclonidine testing conducted by ophthalmologists to cases in which the diagnosis was made entirely on clinical grounds mostly by nonophthalmologists. METHODS: We applied a new search engine to the inpatient and outpatient electronic medical records text at the University of Michigan Medical Center from 1996 to 2018 for Horner syndrome with and without pharmacologic confirmation through ocular instillation of apraclonidine 0.5%. Among apraclonidine-confirmed cases, 159 met inclusion criteria. Among apraclonidine-unconfirmed cases, more than 2,000 cases were identified, so that we included only the first 159 cases that met inclusion criteria. In these 318 cases, we documented patient demographics, ophthalmologic features, imaging, underlying cause, and whether the cause was discovered before or after the diagnosis of Horner syndrome. RESULTS: In the cohort of 159 apraclonidine-confirmed cases of Horner syndrome, a cause was identified in 97 (61%). Procedures in the neck, chest, skull base, and paraspinal region accounted for most of the identified causes, with cervical carotid dissection the next most common cause. In a cohort of 159 cases of Horner syndrome not tested with apraclonidine because the clinical diagnosis appeared firm, procedures again accounted for the largest percentage, but tumor was the next most common cause. In both groups, when a cause for Horner syndrome could be identified, that cause was nearly always known before Horner syndrome was identified. However, in an important minority of cases, mostly involving carotid dissection or tumor, the identification of Horner syndrome was critical to the discovery of those conditions. CONCLUSIONS: The prevalence of causes of Horner syndrome depends on the accrual method. Among pharmacologically-confirmed cases, the cause was often undetermined or due to a preceding neck or chest procedure. Among pharmacologically-unconfirmed cases, a substantial proportion had also been caused by neck and chest procedures, but tumors in that region were also common. When a cause of Horner syndrome was found in both cohorts, it was usually known before Horner syndrome was discovered, making Horner syndrome an afterthought. However, in an important minority of cases where the cause was not yet known, the identification of Horner syndrome was valuable in leading to important diagnoses such as carotid dissection and tumor.

DNA methylation analysis of the temporal artery microenvironment in giant cell arteritis.

OBJECTIVE: To investigate the inflammatory response in giant cell arteritis (GCA) by characterising the DNA methylation pattern within the temporal artery microenvironment. METHODS: Twelve patients with non-equivocal histological evidence for GCA and 12 age-matched, sex-matched and ethnicity-matched controls with normal biopsies were studied. DNA was extracted from the affected portions of temporal artery tissue in patients with GCA and from histologically confirmed normal arteries in controls. Genome-wide DNA methylation status was evaluated using the Illumina Infinium HumanMethylation450 BeadChip Array. Differentially methylated loci between affected and unaffected arterial tissues were identified, and subsequent bioinformatic analysis performed. Immunohistochemistry was used to examine tissue expression patterns in temporal artery biopsies. RESULTS: We identified 1555 hypomethylated CG sites (853 genes) in affected temporal artery tissue from patients with GCA compared with normal controls. Gene ontology enrichment analysis of hypomethylated genes revealed significant representation in T cell activation and differentiation pathways, including both TH1 and TH17 signatures. Our DNA methylation data suggest a role for increased activity of the calcineurin/nuclear factor of activated T cells (NFAT) signalling pathway in GCA, confirmed by immunohistochemistry showing increased expression and nuclear localisation of NFAT1. NFAT signalling downstream targets such as interleukin (IL)-21/IL-21R and CD40L were overexpressed in GCA-affected arteries. Further, proinflammatory genes including TNF, LTA, LTB, CCR7, RUNX3, CD6, CD40LG, IL2, IL6, NLRP1, IL1B, IL18, IL21, IL23R and IFNG were hypomethylated in the cellular milieu of GCA arteries. CONCLUSIONS: We characterised the inflammatory response in GCA-affected arteries using 'epigenetic immunophenotyping' and identified molecules and pathways relevant to disease pathogenesis in GCA.

Clinical Utility of Acetylcholine Receptor Antibody Testing in Ocular Myasthenia Gravis.

IMPORTANCE: The sensitivity of acetylcholine receptor (AChR) antibody testing is thought to be lower in ocular myasthenia gravis (OMG) compared with generalized disease, although estimates in small-scale studies vary. There is little information in the literature about the implications of AChR antibody levels and progression from OMG to generalized myasthenia gravis. OBJECTIVES: To test the hypothesis that serum AChR antibody testing is more sensitive in OMG than previously reported and to examine the association between AChR antibody levels and progression from OMG to generalized myasthenia gravis. DESIGN, SETTING, AND PARTICIPANTS: A retrospective, observational cohort study was conducted of 223 patients (mean [SD] age, 59.2 [16.4] years; 139 [62.3%] male) diagnosed with OMG between July 1, 1986, and May 31, 2013, at 2 large, academic medical centers. MAIN OUTCOMES AND MEASURES: Baseline characteristics, OMG symptoms, results of AChR antibody testing, and progression time to generalized myasthenia gravis (if this occurred) were recorded for each patient. Multiple logistic regression was used to measure the association between all clinical variables and antibody result. Kaplan-Meier survival analysis was performed to examine time to generalization. RESULTS: Among the 223 participants, AChR antibody testing results were positive in 158 participants (70.9%). In an adjusted model, increased age at diagnosis (odds ratio [OR], 1.03; 95% CI, 1.01-1.04; P = .007) and progression to generalized myasthenia gravis (OR, 2.92; 95% CI, 1.18-7.26; P = .02) were significantly associated with positive antibody test results. Women were less likely to have a positive antibody test result (OR, 0.36; 95% CI, 0.19-0.68; P = .002). Patients who developed symptoms of generalized myasthenia gravis had a significantly higher mean (SD) antibody level than those who did not develop symptoms of generalized myasthenia gravis (12.7 [16.5] nmol/L vs 4.2 [7.9] nmol/L; P = .002). CONCLUSIONS AND RELEVANCE: We demonstrate a higher sensitivity of AChR antibody testing than previously reported in the largest cohort of patients with OMG available to date. Older age, male sex, and progression to generalized myasthenia gravis were significantly associated with a positive antibody test result. In addition, to our knowledge, this is the first report of an association between high AChR antibody levels and progression from OMG to generalized disease.

Papilledema and Vision Loss Caused by Jugular Paragangliomas.

Paragangliomas that arise from the jugular bulb are known to present as masses in the neck or with hearing loss, pulsatile tinnitus, and lower cranial nerve palsies. Much less recognized is their tendency to cause increased intracranial pressure and papilledema by obstructing jugular venous outflow. Only 7 such cases have been reported and with minimal ophthalmic documentation. We describe 3 more cases to provide additional documentation and to emphasize that paragangliomas are a potential cause of the pseudotumor cerebri syndrome, and that papilledema may be overlooked when a jugular paraganglioma is diagnosed or after it has been treated. Such lapses have led to disabling vision loss from damage to the optic nerves in long-standing papilledema.

Eye care providers' attitudes towards tele-ophthalmology.

BACKGROUND: The rapid rise of e-health and remote care systems will likely change the practice patterns of ophthalmologists. Although telemedicine practices are thriving in many specialties of medicine, telemedicine for ophthalmology has been limited primarily to asynchronous care for diabetic retinopathy. The goal of this research was to evaluate perspectives on and familiarity with telemedicine among eye care providers at a large tertiary-care medical center via an anonymous, descriptive survey. RESULTS: In total, 58 eye care physicians completed surveys (response rates of 86% for physicians-in-training and 49% for faculty physicians, respectively). Although a majority of both faculty and physicians-in-training were willing to participate in telemedicine services, trainees were more likely to be willing to interpret photographs than faculty (p=0.04). Most respondents (71%) indicated that they did not use telemedicine. Over half had received photographs (via phone or e-mail) for interpretation from referring physicians (54%) or patients (56%) within the past 3 months. A majority of providers (82%) would be willing to participate in telemedicine for consultations and for interpreting photographs, but a majority (59%) had low confidence in remote care for providing an opinion on patient care. CONCLUSIONS: Most eye care providers viewed telemedicine as part of the future of eye care but were concerned about the use of telemedicine. Although most providers did not practice telemedicine, over half of them were comfortable managing eye care consultations (including patients' photographs) via the Internet.

CDX2 is a useful marker of intestinal-type differentiation: a tissue microarray-based study of 629 tumors from various sites.

CONTEXT: CDX2, a critical nuclear transcription factor for intestinal development, is expressed in intestinal epithelium and adenocarcinomas. OBJECTIVES: To determine if CDX2 is a useful marker for intestinal-type differentiation and to correlate tumor histology with CDX2 staining in colorectal adenocarcinomas. DESIGN: Tissue microarrays from 71 colorectal adenocarcinomas, 31 hepatocellular carcinomas, 47 lung adenocarcinomas, 55 squamous cell carcinomas of the lung, 69 neuroendocrine carcinomas of the lung and 43 of the pancreas, 57 pancreatic adenocarcinomas, and 256 endometrial adenocarcinomas were stained with antibody against CDX2. RESULTS: CDX2 staining was positive in 51 (71.8%) of 71 colorectal cancers, including 38 (74.5%) of 51 well- or moderately differentiated tumors and 13 (65.0%) of 20 high-grade tumors. Of the high-grade tumors, 5 (71.4%) of 7 mucinous, 3 (100%) of 3 signet ring cell, and 5 (50.0%) of 10 poorly differentiated tumors were positive. Other tumors showing occasional CDX2 staining included 1 of 30 well- or moderately differentiated neuroendocrine carcinomas of the lung and 2 of 43 from the pancreas, 1 of 47 lung adenocarcinomas, 3 of 57 pancreatic adenocarcinomas, and 15 of 256 endometrial carcinomas. Hepatocellular, poorly differentiated neuroendocrine carcinoma of the lung and squamous cell carcinomas of the lung were not immunoreactive for CDX2. CONCLUSIONS: CDX2 is a useful marker for intestinal-type differentiation, is rarely seen in tumors from the other sites evaluated, and may be useful in determining the site of origin for some metastatic tumors. However, CDX2 is not a sensitive marker for poorly differentiated colorectal carcinoma.