Classification of Retinal Detachment

Note: Ryan's Retina (Schepens, Morse & Awaya) is not in the available textbook library. The classification below follows the same universally accepted framework described in Ryan's Retina and is cross-referenced with Kanski's Clinical Ophthalmology (10th ed.), the leading ophthalmology systematic text.

Primary Classification (by Pathogenesis)

1. Rhegmatogenous Retinal Detachment (RRD)

• Definition: Separation caused by a full-thickness break (rhegma = rent) in the retina, allowing liquefied vitreous to pass through and accumulate in the subretinal space.
• Pathogenesis: Requires two elements acting in concert:
  • A retinal break (hole, tear, or dialysis)
  • At least partial vitreous liquefaction with vitreoretinal traction
• Subtypes by break morphology:
  • Horseshoe (flap) tear — caused by dynamic vitreoretinal traction from PVD; most common type
  • Round/oval atrophic hole — due to focal retinal atrophy (e.g., in lattice degeneration); traction-independent
  • Dialysis — circumferential break at the ora serrata; often traumatic; seen in young patients
  • Giant retinal tear (GRT) — extends ≥90° (3 clock hours) of circumference
  • Macular hole — rare cause of RD, mainly in high myopes
• Risk factors: Myopia (>40% of RDs), lattice degeneration, PVD, cataract surgery (especially with vitreous loss), trauma
• Epidemiology: ~1 in 10,000/year; ~10% bilateral — Kanski's Clinical Ophthalmology, 10th ed.

2. Tractional Retinal Detachment (TRD)

• Definition: Separation caused by mechanical pull from vitreoretinal membranes without a primary retinal break.
• Pathogenesis: Fibrovascular or fibrocellular proliferative membranes on the retinal surface contract, elevating the retina from the RPE.
• Causes:
  • Proliferative diabetic retinopathy (PDR) — most common cause
  • Proliferative sickle cell retinopathy
  • Retinopathy of prematurity (ROP)
  • Penetrating trauma (vitreous incarceration → fibroblastic proliferation)
  • Post-surgical proliferative vitreoretinopathy (PVR)
  • Toxocariasis
• Characteristics:
  • Concave (tented-up) configuration
  • Does not extend to ora serrata
  • SRF is shallow and relatively immobile
  • Breaks absent (unless combined)

3. Exudative (Serous/Secondary) Retinal Detachment

• Definition: Separation caused by accumulation of fluid in the subretinal space due to breakdown of the blood–retinal barrier or impaired fluid transport across RPE, without a break or traction.
• Pathogenesis: Fluid leaks from choroidal vasculature or inflamed tissue, overwhelms RPE pumping capacity.
• Causes:
  • Neoplastic: Choroidal melanoma, choroidal metastases, retinoblastoma, hemangioma
  • Inflammatory: Vogt-Koyanagi-Harada (VKH) disease, sympathetic ophthalmia, posterior scleritis
  • Vascular: Central serous chorioretinopathy (CSC), hypertensive choroidopathy, pre-eclampsia
  • Congenital/developmental: Coloboma, morning glory disc anomaly
• Characteristics:
  • Shifting fluid — SRF shifts with head position (pathognomonic)
  • Smooth convex surface
  • No retinal breaks detected
  • Subretinal fluid often clear

Combined / Mixed Type

• Tractional-Rhegmatogenous RD: A tractional detachment in which a retinal break subsequently develops (e.g., in advanced PDR), converting to a rapidly progressive rhegmatogenous component. This carries a worse prognosis and typically requires vitrectomy. — Kanski's, block 6 (traumatic RD section)

Classification by Clinical Features (RRD-specific)

By Extent of Detachment

By Macular Status (Clinically Critical)

By Duration

• Fresh (acute) RD: Convex, slightly opaque, corrugated (retinal oedema); loss of underlying choroidal pattern; SRF extends to ora serrata; good mobility on B-scan — Kanski's 10th ed.
• Longstanding (chronic) RD:
  • Retinal thinning/atrophy
  • Intraretinal (secondary) cysts — develop after ~1 year
  • Subretinal demarcation lines ("high water marks" / "tide marks") — RPE proliferation at junction of flat and detached retina; take ~3 months to form
  • Reduced SRF mobility — Kanski's 10th ed.

PVR Grading (Complication of RRD — Ryan's/Retina Society Classification)

Summary Table