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H31.423

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🧬 ICD-10-CM H31.423 — Serous Choroidal Detachment, Bilateral

Billable Code Confirmed

ICD-10 CM H31.423 is a valid, billable 6-character ICD-10-CM code for FY2025. All six characters are present: H31 (category) + .4 (choroidal detachment) + 2 (serous) + 3 (bilateral). No 7th character is required for this code.

Non-Billable Parent Codes — Never Submit These

  • ❌ H31.42 — 5-character header — missing laterality character

  • ❌ H31.4 — 4-character header — missing etiology and laterality

    Always submit H31.423 (all 6 characters) when bilateral involvement is documented.

Clinical Context: Serous vs. Hemorrhagic

It is critical to differentiate a serous detachment (H31.423) from a hemorrhagic detachment (H31.413). Serous effusions contain transudate/exudative clear fluid and often resolve with medical therapy (cycloplegics/steroids) or simple surgical drainage. Hemorrhagic effusions contain blood, present with sudden severe pain, carry a much higher risk of permanent visual loss, and often require more complex vitreo-retinal surgical intervention. Code selection strictly depends on the documented fluid type.

🔍 Code Description

ICD-10-CM H31.423 classifies a bilateral serous choroidal detachment (also commonly referred to as a choroidal effusion or ciliochoroidal effusion). This condition occurs when serous fluid accumulates in the suprachoroidal space (the potential space between the choroid and the sclera).

Bilateral presentation is relatively uncommon compared to unilateral presentations and usually points to systemic or bilateral etiologies rather than a localized single-eye event. Common causes for a bilateral presentation include:

  • Uveal Effusion Syndrome: A rare, idiopathic condition often seen in nanophthalmic (short axial length) eyes.

  • Bilateral Ocular Surgery / Hypotony: Such as bilateral trabeculectomies or glaucoma drainage devices resulting in bilateral low intraocular pressure (hypotony).

  • Systemic Inflammatory/Autoimmune Conditions: Such as Vogt-Koyanagi-Harada (VKH) disease.

  • Medication-Induced: Systemic medications like Topiramate can cause bilateral ciliochoroidal effusions and secondary angle-closure glaucoma.

When effusions become so large that the choroidal domes touch in the center of the vitreous cavity, they are referred to as “kissing choroidals,” which constitutes an ocular emergency to prevent permanent retinal adhesion and vision loss.2

🌳 Code Tree / Hierarchy

H31 Other disorders of choroid
│  
├── H31.4 Choroidal detachment ❌ Non-billable
│ │  
│ ├── H31.40 Unspecified choroidal detachment
│ ├── H31.41 Hemorrhagic choroidal detachment
│ │  
│ └── H31.42 Serous choroidal detachment ❌ Non-billable
│   │
│   ├── H31.421 Serous choroidal detachment, right eye
│   ├── H31.422 Serous choroidal detachment, left eye
│   ├── H31.423 SEROUS CHOROIDAL DETACHMENT, BILATERAL ◀ THIS CODE ✅
│   └── H31.429 Serous choroidal detachment, unspecified eye

✅ Includes

The following clinical terms and diagnoses map to H31.423 when documented as bilateral:

  • Bilateral ciliochoroidal effusion

  • Bilateral serous choroidal effusion

  • Bilateral uveal effusion (serous)

  • Annular serous choroidal detachment, bilateral

  • Kissing choroidals (serous nature), bilateral

❌ Excludes

Excludes1 — Cannot be coded together

The Excludes1 note indicates that the following conditions cannot be coded alongside H31.423. If the patient has these conditions, you must code them instead or assess if they are entirely separate disease processes:

  • Hemorrhagic choroidal detachment (H31.41-)

  • Retinal detachment with retinal break (H33.0-)

  • Serous retinal detachment (H33.20)

Co-existing Retinal and Choroidal Detachments

If a patient has both a choroidal detachment and a rhegmatogenous retinal detachment in the same eye, the retinal detachment (H33.0-) takes sequencing precedence as the more severe and primary diagnosis driving the surgical intervention.

🛠️ CPT Procedural Crosswalk — wRVU & Assistant Payable Status

Because H31.423 is a diagnosis code, it does not have wRVUs or Assistant Surgeon indicators itself. Below is a crosswalk of the most common CPT codes billed alongside H31.423, complete with their wRVU and Assistant Surgeon payable statuses.3

CPT CodeDescriptionwRVU (Facility)Asst. Surgeon Payable?Co-Surgeon Payable?
67015Aspiration or release of vitreous, subretinal or choroidal fluid, pars plana approach (Choroidal Tap / Drainage)14.80Yes (Indicator 2) — Justification requiredNo (Indicator 0)
67036Vitrectomy, mechanical, pars plana approach14.86Yes (Indicator 2) — Justification requiredNo (Indicator 0)
76512Ophthalmic ultrasound, diagnostic; B-scan (with or without superimposed non-quantitative A-scan)0.45No (Indicator 0)No (Indicator 0)
92225Ophthalmoscopy, extended, with retinal drawing (initial)0.45No (Indicator 0)No (Indicator 0)
99222Inpatient hospital care, Level 22.61No (Indicator 0)No (Indicator 0)
Note: wRVU values are estimates based on the standard CMS Physician Fee Schedule. Check current year exact values.

Diagnostic Imaging Note

Ultrasound B-scan (76512) is the gold standard for diagnosing a choroidal effusion when the view to the posterior pole is obscured or to confirm the fluid is serous (echolucent) rather than hemorrhagic (echodense). It is highly supported by H31.423 for medical necessity.

💊 Coding Scenarios

Scenario 1 — Medical Management of Topiramate-Induced Effusions

Clinical Vignette: A 42-year-old female presents to the ER with sudden onset bilateral blurred vision and ocular pain. She recently started Topiramate for migraines. Examination reveals bilateral shallow anterior chambers and elevated IOP. B-scan ultrasound confirms bilateral 360-degree ciliochoroidal effusions (serous) with secondary angle closure. The physician diagnoses Topiramate-induced bilateral serous choroidal effusions. She is started on heavy topical cycloplegics (atropine) and aqueous suppressants, and instructed to discontinue Topiramate.

CPT / HCPCS:

  • 99284 — Emergency department visit, high complexity

  • 76512 — Ophthalmic ultrasound, B-scan, bilateral (modifier -26 if professional component only)

ICD-10-CM:

  • H31.423 — Serous choroidal detachment, bilateral (Primary ocular finding)

  • H40.2230 — Chronic angle-closure glaucoma, bilateral, stage unspecified (Secondary to the effusion)

  • T42.4X5A — Adverse effect of antiepileptic and sedative-hypnotic drugs, initial encounter (To capture the Topiramate etiology)

Scenario 2 — Post-Operative Hypotony with “Kissing” Choroidals

Clinical Vignette: A 68-year-old male is 1 week post-op from bilateral Xen gel stent implantations for refractory glaucoma. He complains of rapidly decreasing vision in both eyes. IOP is 2 mmHg OD and 3 mmHg OS. Dilated exam shows massive, appositional (“kissing”) serous choroidal detachments in both eyes. Given the risk of permanent retinal adhesion, he is taken to the OR for bilateral suprachoroidal fluid drainage via pars plana sclerotomies. CPT / HCPCS:

  • 67015-50 — Aspiration/release of choroidal fluid, pars plana approach, bilateral (Use modifier -50 for bilateral procedure)

  • OR: 67015-RT and 67015-LT (Depending on specific payer preference for bilateral surgical billing)

ICD-10-CM:

  • H31.423 — Serous choroidal detachment, bilateral

  • H44.40 — Unspecified hypotony of eye (Or specific bilateral hypotony code if applicable)

  • H59.813 — Other postprocedural complications of eye and adnexa, bilateral (To capture the complication status)

Modifier 78 vs 79 for Post-Op Complications

In Scenario 2, if the choroidal drainage (67015) occurs during the 90-day global period of the initial glaucoma surgeries, and requires a return to the operating room for a related complication, append modifier -78 (Unplanned return to OR) to the surgical CPT code.

Scenario 3 — Uveal Effusion Syndrome Evaluation

Clinical Vignette: A 55-year-old hyperopic male with nanophthalmos is referred for slowly progressive peripheral vision loss in both eyes. Extended ophthalmoscopy reveals chronic, shifting bilateral serous choroidal detachments. Optical coherence tomography (OCT) and B-scan confirm the presence of suprachoroidal fluid without retinal breaks or traction. Diagnosed with Uveal Effusion Syndrome. Scheduled for bilateral scleral windows in 2 weeks.

CPT / HCPCS:

  • 92004 — Comprehensive ophthalmological exam, new patient

  • 76512 — B-scan ultrasound

  • 92225 — Extended ophthalmoscopy, initial

ICD-10-CM:

  • H31.423 — Serous choroidal detachment, bilateral

  • Q15.0 — Congenital glaucoma / nanophthalmos (If clinically applicable to capture the underlying anatomic predisposition)

⚠️ Coding Pitfalls and Tips

Pitfall or Tip
❌Do not confuse with serous retinal detachment: Retinal detachments are coded to H33.-. Choroidal detachments are H31.4-.
❌Do not code H31.423 if blood is documented: If the ultrasound or operative report specifies hemorrhagic fluid or a suprachoroidal hemorrhage, you must use H31.413 instead.
❌Missing the underlying cause: Choroidal effusions are rarely spontaneous. Always look for and code the underlying etiology (e.g., hypotony H44.40, adverse drug effect T42.4X5A, or post-op complication H59.813).
✅Bill B-Scans appropriately: B-scan (76512) is standard of care for diagnosing and monitoring the size of a choroidal detachment. Ensure it is linked directly to H31.423.
✅Use modifier 50 correctly: If performing surgical drainage (67015) bilaterally in the same operative session, append modifier -50 (or RT/LT based on payer rules) to reflect the bilateral surgical intervention.

📚 Sources

  1. CMS/NCHS. ICD-10-CM Official Guidelines for Coding and Reporting, FY2025. Tabular List — H31.423 Serous choroidal detachment, bilateral.
  2. American Academy of Ophthalmology (AAO). Basic and Clinical Science Course (BCSC), Section 12: Retina and Vitreous. Choroidal detachments and effusions.
  3. American Medical Association (AMA). CPT 2024/2025 Professional Edition. Surgical procedures: Posterior Segment.

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