Abnormal findings on diagnostic imaging of lung (R91) ICD-10-CM
The R91 code range covers abnormal findings on diagnostic imaging of lung with 3 ICD-10-CM diagnosis codes. 2 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Codes in the R91 Range 3 codes · 2 billable
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the R91 range.
Solitary Pulmonary Nodule
A single lung lesion that is characterized by a small round mass of tissue, usually less than 1 cm in diameter, and can be detected by chest radiography. A solitary pulmonary nodule can be associated with neoplasm, tuberculosis, cyst, or other anomalies in the lung, the CHEST WALL, or the PLEURA.
About the R91 Code Range
ICD-10 code R91 covers abnormal findings identified through diagnostic imaging of the lungs. This section is specifically designed to classify lung abnormalities detected on X-rays, CT scans, or other imaging methods without assigning a definitive diagnosis.
The code R91.1 refers to a solitary pulmonary nodule, which is a single abnormal spot or lesion in the lung seen on imaging. Synonyms like "coin lesion of lung" and "pulmonary nodule following infection by Coccidioides or Pneumocystis" help clarify this code’s use when identifying isolated nodules possibly caused by infections or other conditions. Meanwhile, R91.8 captures various other nonspecific abnormal lung findings, such as "ground glass opacity," "air bronchogram," or "radiologic infiltrate," terms often used to describe less clearly defined changes or increased densities on lung images. These codes are critical when healthcare providers observe abnormal lung imaging results but have not yet confirmed a specific lung disease, ensuring accurate coding for further investigation or follow-up care. Understanding ICD-10 codes for abnormal lung imaging helps facilitate appropriate documentation and communication within medical records and billing systems.
Questions About This Page
How many billable codes are in the R91 range?
Of the 3 codes in this range, 2 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the R91 range classify?
The range classifies abnormal findings on diagnostic imaging of lung. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
