Validating Publicly Available Crosswalks for Translating ICD-9 to ICD-10 Diagnosis Codes for Cardiovascular Outcomes Research

Background On October 1, 2015, the Center for Medicare and Medicaid Services transitioned from the International Classification of Diseases, Ninth Revision ( ICD-9) to the ICD, Tenth Revision ( ICD-10) compendium of codes for diagnosis and billing in health care, but translation between the two is often inexact. Here we describe a validated crosswalk to translate ICD-9 codes into ICD-10 codes, with a focus on complications after carotid revascularization and endovascular aortic aneurysm repair. Methods and Results We devised an 8-step process to derive and validate ICD-10 codes from existing ICD-9 codes. We used publicly available sources, including the General Equivalence Mapping database, to translate ICD-9 codes used in prior work to ICD-10 codes. We defined ICD-10 codes as validated if they were concordant with the initial ICD-9 codes after manual comparison by two physicians. Our primary validation measure was the percent of valid ICD-10 codes out of the total ICD-10 codes obtained during translation. We began with 126 ICD-9 diagnosis codes used for complication identification after carotid revascularization procedures, and 97 ICD-9 codes for complications after endovascular aortic aneurysm procedures. Translation generated 143 ICD-10 codes for carotid revascularization, a 14% increase from the initial 126 codes. Manual comparison demonstrated 98% concordance, with 99% agreement between the reviewers. Similarly, we identified 108 ICD-10 codes for endovascular aortic aneurysm repair, an 11% increase from the initial 97 ICD-9 codes. We again noted excellent concordance and agreement (98% and 100%, respectively). Manual review identified 4 ICD-10 codes incorrectly translated from ICD-9 codes for carotid revascularization, and 3 codes incorrectly translated for endovascular aortic aneurysm repair. Conclusions Algorithms to crosswalk lists of ICD-9 codes to ICD-10 codes can leverage electronic resources to minimize the burden of code translation. However, manual review for code validation may be necessary, with collaboration across institutions for researchers to share their efforts.

The effect of fine-needle aspiration biopsy on the thyroid scan

Fine-needle aspiration biopsy (FNAB) is the most sensitive and specific procedure in diagnosing benign from malignant thyroid nodular disease. The effects of a FNAB on the thyroid scan, however, have never been studied. This assumes importance because a hot nodule on scan has been advocated as useful to differentiate certain benign from malignant follicular neoplasms. Thyroid scans were performed before and after FNAB on 11 patients with nodular thyroid disease and an area of normal or increased uptake either in the nodule or in a contralateral enlarged lobe to determine if the biopsy changed the pattern of isotope uptake. For this study, biopsies were done in the area of normal or increased uptake. In two patients, there was a reduction in isotope concentration in three nodules after FNAB, whereas no change was demonstrable in nine other patients. Review of the literature revealed a number of prior reports of hemorrhage, necrosis, or infarction of thyroid nodules after FNAB. Based on these data and the demonstration of a change in scan pattern in a patient following FNAB, it is concluded that FNAB may decrease the isotope uptake in thyroid nodules; therefore, the concept of clinical judgments being based on the scan pattern after FNAB should be reevaluated.

Fetal sonography and neonatal scintigraphy of a choledochal cyst

A choledochal cyst, observed by ultrasound at 27 wk gestation and diagnosed at 36 wk gestation, was confirmed postpartum by [99mTc]DISIDA cholescintogram. Cystic dilatation of the common bile duct was proven by surgical excision and histological verification. Ultrasonography provides in utero diagnosis of choledochal cyst, often vital for successful management. Technetium-99m DISIDA imaging is a valuable companion for defining function of the cyst.