A National Survey of Practice Patterns

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.

Temporal artery biopsy

Giant cell arteritis is a common vasculitis in patients over the age of 50 years old. If not promptly recognized and aggressively treated with high-dose glucocorticoids, ischemia resulting in permanent vision loss or stroke can occur. Yet, the treatment with high-dose glucocorticoids over a long period of time can be problematic in this particular patient population given their age and associated comorbidities. Temporal artery biopsies (TAB) are an important diagnostic tool to evaluate patients with suspected giant cell arteritis. Herein, we explore indications for TAB and practical points in obtaining a TAB based on available evidence. We review the surgical procedure itself and associated complications. Lastly, we examine common pathological findings and considerations of alternative diagnoses.

Temporal artery biopsy: A technical guide and review of its importance and indications

Temporal artery biopsy (TAB) is a surgical procedure that enables the histological diagnosis of giant cell arteritis (GCA). Performing a TAB requires expertise and a precise approach. Nevertheless, available data supports the value of tissue diagnosis in managing GCA. The current therapeutic recommendation for GCA is long-term glucocorticoid therapy, with an increasing emphasis on the addition of immunosuppressants/biotherapies. Though effective, immunosuppressants and other such biotherapies may put the patient at more risk. Optimizing the diagnosis through tissue evaluation is therefore important in weighing the risks and benefits of initiating therapeutic intervention. We evaluate the evidence supporting the importance of TAB and its indications. We also describe what technical approaches should be used to maximize sensitivity and to avoid possible complications during the procedure.

The Utility of the Bilateral Temporal Artery Biopsy for Diagnosis of Giant Cell Arteritis

OBJECTIVE

A surgical temporal artery biopsy (TAB) is the gold standard for diagnosis of giant cell arteritis (GCA). The necessity of performing a bilateral biopsy remains under debate. The primary objective of this study was to assess the rate of discordance between pathology results in patients who underwent bilateral temporal artery biopsy for suspected GCA.

METHODS

We performed a retrospective review of patients who underwent bilateral temporal artery biopsy for diagnosis of GCA between 2011 and 2020. The primary endpoint was the rate of discordance between specimens for patients with pathology positive GCA. Secondary endpoints included assessments of the sensitivity of pre-operative temporal artery duplex and the effects of specimen length and specialty of referring provider on the diagnostic yield of the biopsy.

RESULTS

During the study period, 310 patients underwent bilateral temporal artery biopsy for diagnosis of giant cell arteritis. These patients were primarily female (73.9%), elderly (mean age 70.8 years), and Caucasian (95.8%). Pre-operative symptoms for patients were typically bilateral (59%) and included headache (81%), vision changes (45.2%), and temporal tenderness (32.6%). Most patients (85.2%) were on pre-operative steroid therapy at the time of surgical biopsy with a mean pre-operative duration of steroid therapy of 15.1 days. Overall, 91 patients (29.4%) had a positive pathologic diagnosis after bilateral temporal artery biopsy. Of these patients, 11 had a positive pathology result in only a single specimen, resulting in a discordance rate of 12.1%. Pre-operative temporal artery duplex demonstrated low sensitivity (27.3%) for identifying patients with pathologic positive disease. There were no significant differences between the pathology positive and negative patients in terms of mean surgical specimen length (1.67 vs 1.64 cm; p = 0.67) or specialty of referring provider (p = 0.73).

CONCLUSIONS

At our institution, we observed a 12.1% discordance rate between pathology results in patients who underwent bilateral temporal artery biopsy for diagnosis of GCA. A pre-operative temporal artery duplex provided little value in identifying patients with biopsy-proven GCA.

Discordance Rate Among Bilateral Simultaneous and Sequential Temporal Artery Biopsies in Giant Cell Arteritis: Role of Frozen Sectioning Based on the Mayo Clinic Experience

Importance

Frozen section temporal artery biopsy (TAB) may prevent a contralateral biopsy from being performed.

Objective

To evaluate the sensitivity and specificity of TAB frozen vs permanent section pathology results for giant cell arteritis (GCA) and determine the discordance rate of bilateral TABs.

Design, Setting, and Participants

In this retrospective cohort study, medical records were reviewed from 795 patients 40 years or older who underwent TAB from January 1, 2010, to December 1, 2018, treated at a single tertiary care center with the ability to perform both frozen and permanent histologic sections. Data were analyzed from January 2019 to December 2020.

Main Outcomes and Measures

Sensitivity and specificity of frozen section TAB for detecting GCA, and discordance rates of bilateral permanent section TAB.

Results

Of the 795 included participants, 329 (41.4%) were male, and the mean (SD) age was 72 (10) years. From the 795 patients with 1162 TABs, 119 patients (15.0%) and 138 TABs had positive findings on permanent section. Of these 119 patients, 103 (86.6%) also had positive results on the frozen section, with 4 false-positives (0.6%) and 20 false-negatives (16.8%). Frozen section had a specificity of 99.4% (95% CI, 98.5-99.8), sensitivity of 83.2% (95% CI, 75.2-89.4), positive predictive value of 96.1% (95% CI, 90.4-98.9), negative predictive value of 96.6% (95% CI, 94.9-97.8), positive likelihood ratio of 140.6 (95% CI, 72.7-374.8), and a negative likelihood ratio of 0.17 (95% CI, 0.11-0.25). Simultaneous bilateral TABs were performed in 60 patients (7.5%) with a 5% discordance rate on permanent section. In comparison, bilateral frozen section-guided sequential TABs were performed in 307 patients (38.6%) with 5.5% discordance based on permanent section. In multivariate models, there was a greater odds of positive findings with age (odds ratio [OR], 1.04; 95% CI, 1.01-1.07; P = .008), vision loss (OR, 2.72; 95% CI, 1.25-5.75; P = .01), diplopia (OR, 3.33; 95% CI, 1.00-10.29; P = .04), headache (OR, 2.32; 95% CI, 1.25-4.53; P = .01), weight loss (OR, 2.37; 95% CI, 1.26-4.43; P = .007), and anorexia (OR, 5.65; 95% CI, 2.70-11.89; P < .001).

Conclusions and Relevance

These results support the hypothesis that negative findings from frozen sections should not be solely relied on to refute the diagnosis of GCA, whereas positive findings from frozen sections can be reliably used to defer a contralateral biopsy pending the permanent section results.

Value of temporal artery biopsy length in diagnosing giant cell arteritis

BACKGROUND

Giant cell arteritis (GCA) is considered an ophthalmological emergency with severe sight and life-threatening sequelae. Temporal artery biopsy (TAB) is the current gold standard for the diagnosis of GCA; however, the required length of biopsy remains an issue of contention in the literature.

METHODS

Retrospective case-control study of a consecutive cohort of 545 patients who had undergone TABs across five hospitals between 1 January 1992 and 1 January 2016. In patients with either positive or negative TABs, we collected age, sex, biopsy length and erythrocyte sedimentation rate (ESR).

RESULTS

A total of 538 patients were included in the final analysis. Of these, 23.4% of TABs were positive, with the average length being 17.6 mm. There was a significant difference in means for positive (19.9 mm) and negative (16.8 mm) biopsies (P = 0.0009). Each millimetre increase in TAB length increased the odds of a positive TAB by 3.4% (P = 0.024). A cut-off point of ≥15 mm increased the odds of a positive TAB by 2.25 compared with a TAB <15 mm (P = 0.003). We also found that ESR ≥50 mm/h was a very strong predictor for a positive TAB result (P < 0.0001).

CONCLUSION

Biopsy length and ESR were significant predictors of a pathological diagnosis of GCA. We also found that the optimal length threshold predictive for GCA was 15 mm in order to avoid a false-negative GCA diagnosis. Although TAB remains the gold standard for diagnosis, clinicians should refer to both clinical and pathological data to guide their management.