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ICD-10-CM 2027 diagnosis code

R91.1Solitary pulmonary nodule

✓ Billable / specific

R91.1 is a valid, billable ICD-10-CM code for solitary pulmonary nodule. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About R91.1

R91.1 is the ICD-10-CM diagnosis code for Solitary pulmonary nodule. It belongs to category R91 (abnormal findings on diagnostic imaging of lung), block R90-R94 (abnormal findings on diagnostic imaging and in function studies, without diagnosis) and chapter 18 (symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within R91 (abnormal findings on diagnostic imaging of lung), R91.1 is specifically for Solitary pulmonary nodule. Related codes cover other nonspecific abnormal finding of lung field (R91.8).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 205 (Other Respiratory System Diagnoses with MCC, relative weight 1.8244) and DRG 206 (Other Respiratory System Diagnoses without MCC, relative weight 0.9257), in MDC 04 (Diseases and Disorders of the Respiratory System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 793.11 (Solitary pulmonary nodule).

Coding notes

Applicable toConditions and synonyms classified to this code
  • Coin lesion lung
  • Solitary pulmonary nodule, subsegmental branch of the bronchial tree

Notes that apply from higher levels

Instructions written at a parent level also apply to R91.1.

Broader instructions also apply from R90-R94 Abnormal findings on diagnostic imaging and in function studies, without diagnosis and Chapter 18: Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified.

Alphabetic index entries

5 entries

Terms in the official ICD-10-CM index that lead to R91.1.

MS-DRG v44.0 grouping

All DRGs →

Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.

ICD-9-CM equivalent

Converter →
  • 793.11Solitary pulmonary noduleexact

From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about R91.1

Is R91.1 billable?

Yes. R91.1 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can R91.1 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict R91.1 as a principal diagnosis.

Is R91.1 a CC or MCC?

No. R91.1 is neither a CC nor an MCC under MS-DRG v44.0.

What DRG does R91.1 group to?

R91.1 is used in the MS-DRG v44.0 logic for MS-DRG 205 (Other Respiratory System Diagnoses with MCC) and MS-DRG 206 (Other Respiratory System Diagnoses without MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.

What is the ICD-9 code for R91.1?

The CMS General Equivalence Mappings map R91.1 to ICD-9-CM 793.11.