H31.402

🧬 ICD-10 CM H31.402 — Unspecified Choroidal Detachment, Left Eye

Quick Reference

Code: H31.402 Type: ICD-10-CM Diagnosis Status: ✅ Billable | Valid FY2026 Chapter: H00-H59 — Diseases of the Eye and Adnexa Laterality: Left Eye HCC Mapped: ❌ No — Not mapped under CMS-HCC V28 MS-DRG: 124 / 125 / 126 (dependent on CC/MCC)

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🩺 Clinical Description

Choroidal detachment occurs when fluid or blood accumulates in the suprachoroidal space — the potential space situated between the choroid and the sclera — causing the choroid to separate from its normal anatomical position adjacent to the retinal pigment epithelium (RPE) and sclera.¹³ The choroid is the densely vascular middle tunic of the globe responsible for the majority of blood supply to the outer retinal layers; any separation from its normal position therefore poses a direct threat to outer retinal perfusion and overall visual function.

ICD-10 CM H31.402 is assigned when the type of choroidal detachment in the left eye is not specified in the clinical documentation — meaning the treating provider has not clearly indicated whether the detachment is of serous (exudative) or hemorrhagic origin. This is a critically important distinction for accurate code assignment: if documentation in any portion of the medical record — including operative reports, radiology reads, or clinic notes — specifies either subtype, a more precise code should always be selected. As a profee coder working inpatient cases, you should initiate a clinical documentation improvement (CDI) query before defaulting to an unspecified code if specificity is clinically determinable.¹

Clinical Features & Presentation

• Patients typically present with decreased or blurred vision, peripheral visual field loss, and occasional deep ocular pain or pressure-like discomfort in the affected left eye¹³
• Fundoscopic exam reveals smooth, dome-shaped, brown-orange peripheral choroidal elevations that may appear lobulated; very large detachments can produce “kissing choroidals” where opposing lobes touch in the mid-vitreous cavity⁷
• B-scan ultrasonography is the diagnostic gold standard — it demonstrates a smooth, convex, highly echogenic choroidal membrane extending from the ciliary body region and is essential for distinguishing choroidal from retinal detachment¹³
• Optical coherence tomography (OCT) can delineate macular involvement and degree of subretinal fluid if present
• Intraocular pressure (IOP) is frequently low (hypotony), particularly in post-surgical presentations⁶

Common Etiologies

• Post-surgical hypotony — the most common etiology, frequently occurring after trabeculectomy, glaucoma drainage device implantation, or vitreoretinal surgery⁶
• Ocular trauma — blunt or penetrating injury to the globe
• Idiopathic — including uveal effusion syndrome, particularly in nanophthalmic eyes
• Drug-induced — topiramate, carbonic anhydrase inhibitors (e.g., dorzolamide-timolol), and certain sulfa-based medications have been implicated⁷
• Inflammatory / uveitic conditions — scleritis, sympathetic ophthalmia
• Intraocular surgical complications — following cataract extraction, scleral buckle placement, or penetrating keratoplasty
• Systemic causes — hypoalbuminemia (nephrotic syndrome, liver disease), severe systemic hypotension

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🌳 Code Tree (Hierarchy)

H00-H59 Diseases of the Eye and Adnexa  
└── H30-H36 Disorders of Choroid and Retina  
└── H31 Other Disorders of Choroid  
└── H31.4 Choroidal Detachment  
├── H31.40 Unspecified Choroidal Detachment  
│ ├── H31.401 Right Eye  
│ ├── H31.402 ◀ LEFT EYE — YOU ARE HERE ✅  
│ ├── H31.403 Bilateral  
│ └── H31.409 Unspecified Eye  
├── H31.41 Hemorrhagic Choroidal Detachment  
│ ├── H31.411 Right Eye  
│ ├── H31.412 Left Eye  
│ ├── H31.413 Bilateral  
│ └── H31.419 Unspecified Eye  
└── H31.42 Serous Choroidal Detachment  
├── H31.421 Right Eye  
├── H31.422 Left Eye  
├── H31.423 Bilateral  
└── H31.429 Unspecified Eye

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6th Character — Laterality Key

6th Character	Meaning
1	Right Eye
2	Left Eye ◀ This code
3	Bilateral
9	Unspecified Eye

Coding Tip — Laterality

Per the ICD-10-CM Official Coding Guidelines, laterality must always be coded to the highest degree of specificity supported by the medical record documentation.¹² If bilateral involvement is documented anywhere in the record — including imaging reports, the H&P, or progress notes — assign H31.403 rather than coding each eye separately. Do not assign H31.409 (unspecified eye) if laterality is documented anywhere in the record, including the ophthalmology consult or radiology report.

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✅ Includes Notes

(No specific Includes note exists at the H31.402 individual code level.) (The following applies at the H31.4 subcategory level:)

• Choroidal detachment NOS (not otherwise specified) — applicable when documentation does not differentiate between serous and hemorrhagic types¹
• Encompasses any separation of the choroid from adjacent structures of an undetermined or undocumented etiology in the left eye²

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❌ Excludes Notes

No Excludes1 or Excludes2 notes exist at the H31.402 individual code level.

Relevant excludes notes appear at the H31 category level and at the H30-H36 block level.

Excludes2 — at Block Level H30-H36

(Excludes2 = “Not included here, but the patient may have both conditions — code both if applicable and documented”)

The following conditions are classified elsewhere and may be coded in addition to H31.402 if separately documented and clinically present:

• Retinal detachment (→ H33.-) — a distinct and separate entity that can co-exist with choroidal detachment
• Disorders of the vitreous body (→ H43.-, H44.-)

Clinical Distinction — Critical for Accurate Code Assignment!

Retinal detachment (H33.x) ≠ Choroidal detachment (H31.4x). These are entirely different anatomical and pathophysiological entities. Retinal detachment involves the neurosensory retina separating from the RPE. Choroidal detachment involves the choroid separating from the sclera within the suprachoroidal space. Both can co-exist in the same patient encounter and both should be coded when documented and confirmed. This is a frequent query point on inpatient cases — do not let one overshadow the other in your documentation review.

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⚕️ HCC Information (Risk Adjustment)

Field	Detail
HCC Mapped?	❌ No
CMS-HCC Model	V28 — Fully implemented CY2026
HCC Category	None — H31.402 does not map to any Hierarchical Condition Category
RAF Impact	None — does not contribute to Risk Adjustment Factor score

HCC Context for CY2026

CMS completed the full three-year phase-in transition to CMS-HCC Model V28 in CY2026, replacing the legacy V24 model entirely.⁸⁹ Unlike certain posterior segment diagnoses — for example, proliferative diabetic retinopathy codes (H35.351-H35.359, HCC 122) or retinal vascular occlusion — unspecified choroidal detachment codes carry no HCC weight under V28. This means that for Medicare Advantage risk adjustment purposes, H31.402 alone will not increase a patient’s RAF score, drive additional plan payment, or trigger hierarchical suppression of other eye-related codes. That said, accurate and complete documentation of the condition remains essential from a clinical integrity and medical record completeness standpoint regardless of HCC impact.

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🏥 MS-DRG (Inpatient)

Especially relevant for your inpatient profee work! H31.402 as a principal diagnosis will group into the eye MDC.

MS-DRG	Title	MDC	Type
124	Other Disorders of the Eye — with MCC	MDC 02 — Eye	Medical
125	Other Disorders of the Eye — with CC	MDC 02 — Eye	Medical
126	Other Disorders of the Eye — without CC/MCC	MDC 02 — Eye	Medical

MS-DRG Assignment Logic

When H31.402 is designated as the principal diagnosis for a medical inpatient admission and no qualifying OR-level surgical procedure is performed, the MS-Grouper will assign MS-DRG 124, 125, or 126 based solely on the presence and weight of secondary diagnoses (CC or MCC) coded on the claim.³ If a qualifying surgical procedure IS performed (e.g., pars plana aspiration of choroidal fluid coded in ICD-10-PCS), the case may instead group to a surgical MS-DRG within MDC 02 — for example MS-DRG 115 or 116 (Extraocular Procedures, Except Orbit). Always verify against your facility’s current MS-Grouper version and verify that your ICD-10-PCS code is OR-level.

CC/MCC Impact on DRG Assignment

Clinical Scenario	Expected MS-DRG
H31.402 + documented MCC (e.g., sepsis A41.9, acute MI I21.9)	124 — with MCC
H31.402 + documented CC (e.g., essential hypertension I10, CKD stage 3 N18.30)	125 — with CC
H31.402 alone, no CC or MCC	126 — without CC/MCC

Profee POA Reminder

Present on Admission (POA) is required on inpatient claims for all reportable diagnoses. Assign POA = Y if the choroidal detachment was present at or before the time of inpatient admission. Assign POA = N if it arose as a new condition during the admission (e.g., post-surgical hypotony after an intraocular surgery performed during that same hospitalization). POA assignment affects hospital reimbursement and quality metrics — flag this on your CDI reviews.¹²

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💊 Related CPT Codes, wRVU & Reimbursement

wRVU Note

Work RVUs listed are approximate values based on the CY2026 CMS Medicare Physician Fee Schedule (MPFS). Always verify against the current MPFS relative value file or your facility/group’s contractual fee schedule before finalizing charges.¹¹

🔬 Diagnostic / Evaluation CPT Codes

CPT Code	Description	wRVU	Global Period	Assistant Payable
92004	Ophthalmological exam, new patient, comprehensive, with dilation	2.67	0 days	N/A — E/M
92014	Ophthalmological exam, established patient, comprehensive, with dilation	1.34	0 days	N/A — E/M
92134	OCT scanning, posterior segment, unilateral or bilateral, with interpretation & report	0.00 (TC/PC split)	0 days	N/A — Diagnostic
76512	Ophthalmic ultrasound, B-scan (with or without non-quantitative A-scan)	0.72	0 days	N/A — Diagnostic

🔧 Therapeutic / Surgical CPT Codes

CPT Code	Description	wRVU (approx.)	Global Period	Asst. Payable (Medicare)
67015	Aspiration or release of vitreous, subretinal, or choroidal fluid, pars plana approach (posterior sclerotomy)	~6.47	90 days	⚠️ Indicator 0 — Payable with supporting documentation
67025	Injection of vitreous substitute, pars plana or limbal approach (fluid-gas exchange), with or without aspiration	~7.84	90 days	⚠️ Indicator 0 — Payable with supporting documentation
67036	Vitrectomy, mechanical, pars plana approach	~14.11	90 days	⚠️ Indicator 0 — Payable with supporting documentation

Assistant at Surgery — Payment Indicator Clarification

Medicare uses a payment indicator system in the MPFS Relative Value file (Column U) to govern assistant-at-surgery reimbursement.¹⁰¹⁶ The indicators are defined as follows:

Indicator	Meaning
0	Payable — but documentation of medical necessity must be submitted with the claim
1	NOT payable — statutory restriction; Medicare will not reimburse regardless of documentation
2	Payable — no restriction applies
9	Concept does not apply (non-surgical code)

Most ophthalmic surgical procedures, including 67015, 67025, and 67036, carry Indicator 0 — meaning an assistant surgeon IS potentially reimbursable, but operative documentation must be submitted with the claim to establish medical necessity for the assistant’s involvement.¹⁶ Always verify the current MPFS RVU file for the exact indicator before billing modifiers -80, -81, -82, or -AS.

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🔖 Commonly Used Modifiers

Modifier	Description	Use With H31.402
-LT	Left side / left eye	✅ Append to CPT codes when treating the left eye
-RT	Right side / right eye	Use if treating the right eye instead
-50	Bilateral procedure	Use if procedure performed on both eyes same operative session
-79	Unrelated procedure or service by same physician during postoperative period of unrelated prior surgery	Use when treating left eye choroidal detachment within the global of a prior unrelated surgery
-78	Return to OR for related procedure during postoperative period	If patient returns to OR for a complication-related procedure within the global of prior surgery
-80	Assistant surgeon — physician	⚠️ Indicator 0 for most eye surgery CPTs — requires documentation
-AS	Assistant at surgery — non-physician (PA, NP, CNS)	⚠️ Same documentation requirement applies; Medicare reimburses at 85% of 16% of MPFS
-51	Multiple procedures	Append to secondary procedures when billing 67015 alongside another surgical CPT on the same date
-25	Significant, separately identifiable E/M on same day as surgical procedure	Use when a distinct E/M is performed on the same day as a minor procedure (e.g., same-day injection and exam)

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📋 Coding Guidelines & Documentation Tips

Query for Specificity Before Assigning Unspecified

Before assigning H31.402, thoroughly review the full medical record — including operative reports, B-scan ultrasound findings, OCT reports, clinical photography notes, and all clinic/consult notes — for documentation of whether the detachment is hemorrhagic or serous/exudative. Clinical language matters:

• Terms like “fluid,” “effusion,” “exudate,” “serous” → consider H31.422 (Serous choroidal detachment, left eye)
• Terms like “blood,” “hemorrhage,” “bleeding,” “hematic” → consider H31.412 (Hemorrhagic choroidal detachment, left eye)
• Only use H31.402 when specificity is truly not determinable from the record after a thorough review and, when appropriate, a clinical query.¹²

• Laterality is mandatory in ICD-10-CM and should never be left unspecified when the record documents a specific eye.¹² H31.409 (unspecified eye) is appropriate only when laterality is genuinely not documented in any portion of the record.
• Post-surgical complications: When the choroidal detachment is documented as a complication of a prior ophthalmic surgical procedure, evaluate whether a H59.- code (Intraoperative and postprocedural complications and disorders of the eye) should be sequenced ahead of H31.402 as the principal/first-listed diagnosis. Per the ICD-10-CM guidelines, complication codes that describe the nature of the complication take sequencing priority.¹²
• Code sequencing for inpatient profee: The condition chiefly responsible for admission is the principal diagnosis. If a patient is admitted specifically for management of left eye choroidal detachment, H31.402 is the principal dx. If admitted for another reason and choroidal detachment is a secondary finding, sequence accordingly and ensure all clinically significant conditions are captured.
• Global period awareness: CPT 67015 carries a 90-day global period. Related E/M services and follow-up visits during the global window are bundled and not separately billable to Medicare unless a significant, separately identifiable E/M service is documented and modifier -25 (pre-op, same-day minor procedure) or modifier -24 (unrelated E/M during post-op global) is appropriately applied.⁵
• NCCI Bundling: CPT 67015 (aspiration/release of vitreous or choroidal fluid) may be bundled with other vitreoretinal procedure codes under NCCI edits. Always check the current NCCI edit table before billing multiple surgical codes on the same operative date.¹⁴

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💡 Coding Examples

Example 1 — Outpatient Office Visit, Established Patient, Left Eye, No Surgery

Scenario: A 65-year-old established Medicare patient presents to a retina specialist with progressive visual decline in the left eye. The physician performs a comprehensive ophthalmological exam with dilation and orders a B-scan ultrasound of the left eye, which is performed and interpreted at the same visit. Findings are consistent with choroidal detachment of the left eye; documentation does not specify hemorrhagic or serous.

CPT: 92014--LT CPT: 76512--LT ICD-10-CM: H31.402

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Example 2 — Surgical Case, Pars Plana Aspiration of Choroidal Fluid, Left Eye

Scenario: A 70-year-old post-trabeculectomy patient presents 10 days after surgery with persistent left eye choroidal detachment, significant hypotony (IOP = 2 mmHg), and visual acuity of 20/400. Conservative management has failed. The vitreoretinal surgeon takes the patient to the OR for aspiration and release of choroidal fluid via the pars plana approach (posterior sclerotomy), left eye. The operative report documents “choroidal detachment” without specifying the type.

CPT: 67015-LT ICD-10-CM (Principal Dx): H31.402

Global & Modifier Consideration

If this procedure falls within the 90-day global period of the prior trabeculectomy, modifier -78 should be appended (unplanned return to OR for a related complication during the postoperative period). Verify that the operative documentation clearly supports the -78 modifier scenario — the post-op complication relationship must be explicitly documented by the surgeon.

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Example 3 — Inpatient Admission, Medical Management, Left Eye, with CC

Scenario: A 77-year-old Medicare patient is admitted for management of left eye choroidal detachment detected at an outpatient visit. History includes essential hypertension and hyperlipidemia. No surgical procedure is performed during the admission. Type of detachment not specified in any portion of the record.

Principal Dx: H31.402 Secondary Dx: I10 (CC — Essential hypertension) Secondary Dx: E78.5 (Hyperlipidemia, unspecified — non-CC/MCC) MS-DRG Assignment: 125 — Other Disorders of the Eye with CC POA: Y (all diagnoses present at admission)

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Example 4 — Bilateral Choroidal Detachment — Left Eye Code Would NOT Apply Alone

Scenario: A post-operative patient develops bilateral choroidal detachments following bilateral cataract surgery performed during the same admission. Both eyes are clearly documented as affected. Type is unspecified.

ICD-10-CM: H31.403 ← Assign bilateral code; do NOT assign H31.401 + H31.402 separately

Per ICD-10-CM guidelines, when a bilateral code exists and bilateral involvement is documented, the bilateral code takes precedence over two unilateral codes.¹²

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Example 5 — Left Eye Choroidal Detachment, Type Now Specified at Follow-Up

Scenario: During an ER visit, H31.402 was assigned based on initial findings. At the follow-up outpatient visit, the B-scan report is finalized and the retina specialist documents “serous choroidal detachment, left eye” in the assessment.

Correct Outpatient Code (Follow-Up Visit): H31.422 (Serous choroidal detachment, left eye)

Reassign to the specific code once documentation supports the specificity. Do not carry forward the unspecified code once the type is clearly established.¹²

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🗂️ Differential Diagnosis Coding

Condition	ICD-10-CM Code	Key Distinction
Hemorrhagic choroidal detachment, left eye	H31.412	Use when hemorrhage is documented — blood in suprachoroidal space
Serous choroidal detachment, left eye	H31.422	Use when fluid/effusion/exudate type is documented
Unspecified choroidal detachment, bilateral	H31.403	Use when both eyes are affected
Retinal detachment, left eye, unspecified	H31.402	Entirely different structure (neurosensory retina vs. choroid)
Unspecified choroidal hemorrhage, left eye	H31.302	Hemorrhage without frank choroidal detachment
Expulsive choroidal hemorrhage, left eye	H31.312	Severe explosive hemorrhage; rare, often intraoperative
Uveal effusion syndrome	H44.812	Idiopathic choroidal/ciliary body effusion; nanophthalmos-associated

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Sources:

1. AAPC Codify — ICD-10-CM H31.402, aapc.com
2. FindACode — ICD-10-CM H31 Group, findacode.com
3. CMS — ICD-10-CM/PCS MS-DRG v37.0 Definitions Manual, cms.gov
4. GenHealth.ai — CPT 67015, genhealth.ai
5. Retinal Physician — Coding Corner, retinalphysician.com
6. EyeWiki — Managing Choroidal Effusions after Glaucoma Filtration Surgery, eyewiki.org
7. NCBI/PMC — Bilateral Choroidal Detachment Case Report PMC9944210, pmc.ncbi.nlm.nih.gov
8. BCA — HCC Updates: Capturing Risk Accurately in 2026, bcarev.com
9. MedPAC — MA Part D CY2027 Comment Letter, medpac.gov
10. Novitas Solutions — Assistant at Surgery Modifiers Fact Sheet, novitas-solutions.com
11. AAPC — Work RVU Calculator, aapc.com
12. CMS — FY2026 ICD-10-CM Official Guidelines for Coding and Reporting, cms.gov
13. Wiley/Clinical Ophthalmology — Choroidal Detachments: What Do Optometrists Need to Know?, onlinelibrary.wiley.com
14. CMS — 2026 NCCI Medicare Coding Policy Manual, cms.gov
15. eMPR — Ophthalmology ICD-10 Codes & Classifications, empr.com
16. FCSO Medicare — Assistant at Surgery Modifiers and Payment Indicators, medicare.fcso.com