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MS-DRG 023 · MDC 01 · Surgical

MS-DRG 023: Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis with MCC or Antineoplastic Implant or Epilepsy with Neurostimulator

Reviewed by QuickIntell RCM Editorial Team · Last reviewed

Data effective
Data currency: IPPS Table 5 FY2027 final rule (effective October 1, 2026); Definitions Manual v44 (effective October 1, 2026). Next CMS release: April 1, 2027 (v44.1 mid-year update), then the FY2028 final rule in August 2027.

Key facts for DRG 023

FY2027 relative weight
5.7420
Higher than 93% of all MS-DRGs
Change vs FY2026
+0.2%
FY2026 weight 5.7300
Geometric mean LOS
7.2 days
Arithmetic mean 10.1 days
MDC
01
Assignment of Diagnosis Codes
Severity level
with MCC (major complication or comorbidity)
Transfer policy
Post-acute transfer DRG
Special-pay DRG

TL;DR

MS-DRG 023 is a surgical group in MDC 01 (Assignment of Diagnosis Codes) at the highest-severity level of its family. CMS assigns it a FY2027 relative weight of 5.7420 with a geometric mean length of stay of 7.2 days and an arithmetic mean of 10.1. Its weight moved up 0.2% from FY2026 (5.7300). That weight is higher than 93% of all surgical and medical MS-DRGs. Its CC/MCC family (DRG 024) spans weights 3.9690 to 5.7420. The v44 Definitions Manual assigns it through 1429 operating room procedures codes and 114 major device implant codes and 369 principal diagnosis codes and 3 neurostimulator codes.

What changed from FY2026 to FY2027

CMS recalibrates every MS-DRG weight annually from the prior year's MedPAR claims. For DRG 023 the FY2027 relative weight is 5.7420 against 5.7300 in FY2026, a rise of 0.21%.

FY2026 versus FY2027 payment factors for MS-DRG 023
MetricFY2026FY2027Change
Relative weight5.73005.7420+0.0120
Geometric mean LOS (days)7.17.2+0.1
Arithmetic mean LOS (days)10.010.1+0.1
Weights shown are the FY2027 final values after the 10% cap on year-over-year reductions where applicable.

CC and MCC family

DRG 023 shares its base definition with 1 other MS-DRG split by severity. The family's weights span 3.9690 to 5.7420, a 1.45× spread, which is the payment effect of documenting qualifying complications and comorbidities.

MS-DRGs in the same base group as DRG 023
DRGTitleFY2027 weightGMLOS
023Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis with MCC or Antineoplastic Implant or Epilepsy with Neurostimulator5.74207.2
024Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis without MCC3.96903.6

Grouper logic (v44 Definitions Manual)

Operating Room Procedures: 1429 ICD-10 codes drive assignment to this group; the first 12 are shown.

Operating Room Procedures codes assigned to DRG 023 (sample)
ICD-10 codeDescription
001607ABypass Cerebral Ventricle to Subgaleal Space with Autologous Tissue Substitute, Open Approach
001607BBypass Cerebral Ventricle to Cerebral Cisterns with Autologous Tissue Substitute, Open Approach
00160JABypass Cerebral Ventricle to Subgaleal Space with Synthetic Substitute, Open Approach
00160JBBypass Cerebral Ventricle to Cerebral Cisterns with Synthetic Substitute, Open Approach
00160KABypass Cerebral Ventricle to Subgaleal Space with Nonautologous Tissue Substitute, Open Approach
00160KBBypass Cerebral Ventricle to Cerebral Cisterns with Nonautologous Tissue Substitute, Open Approach
00160ZBBypass Cerebral Ventricle to Cerebral Cisterns, Open Approach
001637ABypass Cerebral Ventricle to Subgaleal Space with Autologous Tissue Substitute, Percutaneous Approach
001637BBypass Cerebral Ventricle to Cerebral Cisterns with Autologous Tissue Substitute, Percutaneous Approach
00163JABypass Cerebral Ventricle to Subgaleal Space with Synthetic Substitute, Percutaneous Approach
00163JBBypass Cerebral Ventricle to Cerebral Cisterns with Synthetic Substitute, Percutaneous Approach
00163KABypass Cerebral Ventricle to Subgaleal Space with Nonautologous Tissue Substitute, Percutaneous Approach

Major Device Implant: 114 ICD-10 codes drive assignment to this group; the first 12 are shown.

Major Device Implant codes assigned to DRG 023 (sample)
ICD-10 codeDescription
0JH60DZInsertion of Multiple Array Stimulator Generator into Chest Subcutaneous Tissue and Fascia, Open Approach
0JH60DZInsertion of Multiple Array Stimulator Generator into Chest Subcutaneous Tissue and Fascia, Open Approach
0JH60DZInsertion of Multiple Array Stimulator Generator into Chest Subcutaneous Tissue and Fascia, Open Approach
0JH60DZInsertion of Multiple Array Stimulator Generator into Chest Subcutaneous Tissue and Fascia, Open Approach
0JH60DZInsertion of Multiple Array Stimulator Generator into Chest Subcutaneous Tissue and Fascia, Open Approach
0JH60DZInsertion of Multiple Array Stimulator Generator into Chest Subcutaneous Tissue and Fascia, Open Approach
0JH60EZInsertion of Multiple Array Rechargeable Stimulator Generator into Chest Subcutaneous Tissue and Fascia, Open Approach
0JH60EZInsertion of Multiple Array Rechargeable Stimulator Generator into Chest Subcutaneous Tissue and Fascia, Open Approach
0JH60EZInsertion of Multiple Array Rechargeable Stimulator Generator into Chest Subcutaneous Tissue and Fascia, Open Approach
0JH60EZInsertion of Multiple Array Rechargeable Stimulator Generator into Chest Subcutaneous Tissue and Fascia, Open Approach
0JH60EZInsertion of Multiple Array Rechargeable Stimulator Generator into Chest Subcutaneous Tissue and Fascia, Open Approach
0JH60EZInsertion of Multiple Array Rechargeable Stimulator Generator into Chest Subcutaneous Tissue and Fascia, Open Approach

Principal Diagnosis: 369 ICD-10 codes drive assignment to this group; the first 12 are shown.

Principal Diagnosis codes assigned to DRG 023 (sample)
ICD-10 codeDescription
A0221Salmonella meningitis
A066Amebic brain abscess
A170Tuberculous meningitis
A171Meningeal tuberculoma
A1781Tuberculoma of brain and spinal cord
A1782Tuberculous meningoencephalitis
A1783Tuberculous neuritis
A1789Other tuberculosis of nervous system
A2781Aseptic meningitis in leptospirosis
A2789Other forms of leptospirosis
A390Meningococcal meningitis
A3981Meningococcal encephalitis

Neurostimulator: 3 ICD-10 codes drive assignment to this group.

Neurostimulator codes assigned to DRG 023 (sample)
ICD-10 codeDescription
0NH00NZInsertion of Neurostimulator Generator into Skull, Open Approach
0NH00NZInsertion of Neurostimulator Generator into Skull, Open Approach
0NH00NZInsertion of Neurostimulator Generator into Skull, Open Approach

Documentation and denial exposure

As a surgical DRG, assignment depends on a qualifying operating-room procedure being coded from the operative report; a missing or non-OR procedure code drops the stay into a medical DRG in MDC 01 with a lower weight. Because this family splits by severity, auditors target CC and MCC capture: each secondary diagnosis must be documented as present, monitored, evaluated or treated during the stay to survive a DRG-validation review. Typical inpatient denial codes for this group: CARC 16 (claim lacks information needed to group the stay), CARC 50 (the admission or procedure is judged not medically necessary), CARC 97 (a service is bundled into the DRG payment).

How QuickIntell uses DRG 023 data

QuickCode groups inpatient encounters against the current v44 logic, flags CC and MCC candidates that lack supporting documentation, and shows the weight difference across the family before the claim drops. QuickScribe captures the attending's language that supports severity, and QuickRCM works DRG-validation denials with the grouper evidence attached.

Frequently asked questions — DRG 023

What is MS-DRG 023?

MS-DRG 023 is "Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis with MCC or Antineoplastic Implant or Epilepsy with Neurostimulator", a surgical Medicare Severity Diagnosis-Related Group in MDC 01, Assignment of Diagnosis Codes. Medicare pays inpatient stays grouped here at the hospital's base rate multiplied by the DRG relative weight.

What is the FY2027 relative weight for DRG 023?

The FY2027 relative weight is 5.7420 (IPPS final rule Table 5, effective October 1, 2026). In FY2026 it was 5.7300, a change of +0.2%.

What is the average length of stay for DRG 023?

CMS reports a geometric mean length of stay of 7.2 days and an arithmetic mean of 10.1 days for FY2027. The geometric mean is used for transfer-payment calculations.

Which DRGs are in the same CC/MCC family as 023?

DRG 024 (Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis without MCC, weight 3.9690). The family's weights range from 3.9690 to 5.7420, so documented complications and comorbidities change payment materially.

What documentation supports the severity level of DRG 023?

DRG 023 requires at least one secondary diagnosis on the CMS Major Complication or Comorbidity list, documented as present and clinically addressed during the stay (monitored, evaluated, treated or extending the stay). Conditions such as acute respiratory failure, severe sepsis or acute kidney injury with specified cause qualify only when the attending's note states the diagnosis itself, not just the lab values. Recovery auditors downgrade this group to the CC or base level when the MCC rests on an unconfirmed query or a resolved historical condition, so the query response and the discharge summary must agree.

Which codes group to DRG 023?

The v44 Definitions Manual lists 1429 operating room procedures codes and 114 major device implant codes and 369 principal diagnosis codes and 3 neurostimulator codes for this group. Examples from the operating room procedures list: 001607A (Bypass Cerebral Ventricle to Subgaleal Space with Autologous Tissue Substitute, Open Approach); 001607B (Bypass Cerebral Ventricle to Cerebral Cisterns with Autologous Tissue Substitute, Open Approach); 00160JA (Bypass Cerebral Ventricle to Subgaleal Space with Synthetic Substitute, Open Approach); 00160JB (Bypass Cerebral Ventricle to Cerebral Cisterns with Synthetic Substitute, Open Approach).

Is DRG 023 a post-acute transfer DRG?

Yes. CMS flags DRG 023 under the post-acute care transfer policy, so a discharge to a qualifying post-acute setting before the geometric mean length of stay is paid a per-diem amount rather than the full DRG payment. It is also a special-pay DRG.

Sources

Every figure on this page is taken from the CMS publications below, as released by the Centers for Medicare & Medicaid Services. Projection built 2026-10-01. Verify against the primary file before billing or contracting decisions.

Disclaimer

This page is an operational reference compiled from the CMS IPPS FY2027 final rule (Table 5) and the v44 ICD-10 MS-DRG Definitions Manual. Relative weights are national factors; actual payment depends on each hospital's wage-adjusted base rate, add-ons, outliers and transfer adjustments. Nothing here is legal, clinical or billing advice; verify grouping against your encoder and the published CMS files.