Retinal Detachment

Slide 1 · Retinal Detachment

Mechanisms, morphology, and clinicopathologic interpretation

Pathology • Retinal anatomy • Mechanism

Dr Abu Suraih Sakhri

MBBS, MD (Pathology)

www.abusuraihsakhri.com

Slide 2 · Learning outcomes

Define retinal detachment anatomically as separation of neurosensory retina from retinal pigment epithelium.

Distinguish retinal-break, exudative, and tractional mechanisms using the retinal interface.

Relate vitreous change and posterior hyaloid traction to full-thickness retinal tears.

Explain chronic photoreceptor changes, proliferative vitreoretinopathy, and therapeutic principles.

Apply the mechanism-based differential to retinal vascular disease and clinical presentations.

Slide 3 · Retinal detachment: The defining tissue plane

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Neurosensory retina

Subretinal fluid / potential space

Retinal pigment epithelium

Choroid

Reading the schematic

The neurosensory retina separates from the retinal pigment epithelium (RPE).

The space between the two structures becomes occupied by fluid.

The identity of the mechanism—not merely separation—determines the classification.

Slide 4 · Normal orientation: Vitreous, retina, RPE, choroid

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Neurosensory retina

Retinal pigment epithelium

Choroid

Reading the schematic

The internal limiting membrane borders the vitreous cavity.

The neurosensory retina contains the photoreceptor apparatus.

The RPE forms the outer interface; The choroid lies beyond it.

Slide 5 · Why the retina is vulnerable to separation

Neurosensory retina and RPE are closely apposed but distinct embryologic layers.

The RPE supports maintenance of photoreceptor outer segments.

Loss of the interface interrupts that normal structural relationship.

Longer-standing detachment may be accompanied by loss of photoreceptor outer segments.

Slide 6 · A mechanism-based framework

Break permits fluid entry

RPE or vascular injury causes exudation

Fibrovascular membranes exert traction

Each route separates retina from RPE

Robbins groups disease by the presence or absence of a retinal break.

Clinically, traction is also distinguished as an important non-break mechanism.

Slide 7 · Two textbook categories: Retinal break present or absent

Rhegmatogenous

Nonrhegmatogenous

Full-thickness retinal defect

Liquefied vitreous enters through tear

Posterior hyaloid traction may initiate break

No retinal break required

Exudation or RPE injury permits fluid collection

Traction may also separate retina without a break

Slide 8 · Clinical mechanism categories and textbook terminology

Clinical descriptor

Essential mechanism

Robbins grouping

Rhegmatogenous

Full-thickness break with vitreous access

Rhegmatogenous

Exudative / serous

Fluid accumulates without a break

Nonrhegmatogenous

Tractional

Contracting fibrovascular membrane

Usually nonrhegmatogenous initially

Combined

Traction produces a secondary break

Both mechanisms can coexist

Slide 9 · The break is a pathologic discriminator

A full-thickness defect directly communicates the vitreous cavity with the subretinal space.

A detached retina with no break requires investigation of other driving mechanisms.

Strong traction can convert an initially non-break detachment into a combined detachment.

Slide 10 · The RPE–photoreceptor interface

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Neurosensory retina

Retinal pigment epithelium

Choroid

Reading the schematic

Photoreceptors lie on the RPE side of the neurosensory retina.

RPE integrity is essential for maintenance of photoreceptor outer segments.

Detachment separates photoreceptors from the RPE support surface.

Slide 11 · Retinal response to injury

The neurosensory retina is derived from the diencephalon.

Like neural tissue, injured retina may respond through gliosis.

Retinal glial cells contribute to membranes seen in proliferative vitreoretinopathy.

This reparative response can become mechanically detrimental.

Slide 12 · Vitreous aging changes the retinal interface

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Neurosensory retina

Retinal pigment epithelium

Choroid

Hyaloid separation

Reading the schematic

The adult vitreous humor is avascular.

Aging vitreous may liquefy and structurally collapse.

The posterior vitreous face (posterior hyaloid) may separate from retina.

Slide 13 · Aging vitreous: The critical sequence

Vitreous liquefaction

Structural collapse

Posterior hyaloid separation

Occasional focal traction

Tears occur when separation is not clean

Posterior vitreous detachment (PVD) is common with aging.

PVD is not itself equivalent to retinal detachment.

Slide 14 · Posterior vitreous detachment is not retinal detachment

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Neurosensory retina

Retinal pigment epithelium

Choroid

Hyaloid separation

Reading the schematic

PVD: Posterior hyaloid separates from the internal limiting membrane.

Retinal detachment: Neurosensory retina separates from the RPE.

These are anatomically distinct tissue planes.

Slide 15 · Clean versus incomplete hyaloid separation

Clean PVD

Focally adherent PVD

Hyaloid detaches from retinal surface

No tear is inherently implied

Retina remains attached to RPE

Strong focal vitreoretinal adhesion persists

Hyaloid movement pulls retina locally

Full-thickness retinal tear may follow

Slide 16 · Focal adhesion converts movement into traction

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Neurosensory retina

Retinal pigment epithelium

Choroid

Residual adhesion

Reading the schematic

The posterior hyaloid remains attached at a point of unusually strong adhesion.

Separation elsewhere transmits force to the remaining attachment.

Traction is concentrated in the retinal tissue at that point.

Slide 17 · From traction to a full-thickness retinal tear

Posterior vitreous detachment

Persistent focal adhesion

Traction at internal limiting membrane

Retinal tissue tears

A full-thickness retinal break develops

The tear creates a pathway for liquefied vitreous.

Tissue-plane disruption precedes the fluid-mediated detachment.

Slide 18 · Rhegmatogenous detachment: Fluid enters via a break

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Full-thickness

Tear

Neurosensory retina

Subretinal fluid / potential space

Retinal pigment epithelium

Choroid

Reading the schematic

The tear spans the full retinal thickness.

Liquefied vitreous traverses the retinal defect.

Fluid collects between neurosensory retina and RPE.

Slide 19 · Rhegmatogenous detachment: Four linked events

Vitreous collapse

Hyaloid traction

Full-thickness tear

Subretinal fluid

Neurosensory retina separates from RPE

A break and fluid movement together explain the detachment.

Removing traction is a central surgical principle.

Slide 20 · Fluid access determines the separation plane

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Full-thickness

Tear

Neurosensory retina

Subretinal fluid / potential space

Retinal pigment epithelium

Choroid

Reading the schematic

The retinal defect opens the vitreous compartment to the potential subretinal space.

The RPE itself need not be the primary site of injury.

Fluid undermines the detached neurosensory retina.

Slide 21 · Retinal tear versus retinal detachment

Retinal tear

Retinal detachment

Full-thickness focal defect

May become an entry point for fluid

Anatomically a break in neurosensory tissue

Separation of retina from RPE

Subretinal fluid occupies the intervening space

May extend away from original break

Slide 22 · Break recognition: Clinical significance

Finding a full-thickness retinal break favors rhegmatogenous detachment.

An apparent small break may explain a more extensive separation.

The clinical goal is to locate retinal breaks and assess the extent of detachment.

Slide 23 · Vitreoretinal concepts that must not be conflated

Structure or event

Plane involved

Immediate significance

Posterior hyaloid

Between vitreous and internal limiting membrane

Can exert traction during PVD

Retinal tear

Across neurosensory retinal thickness

Provides access for vitreous fluid

Retinal detachment

Between retina and RPE

Disrupts photoreceptor–RPE interface

Subretinal fluid

Retina–RPE potential space

Maintains physical separation

Slide 24 · Acute rhegmatogenous detachment: Outer segments persist

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Full-thickness

Tear

Neurosensory retina

Subretinal fluid / potential space

Retinal pigment epithelium

Choroid

Reading the schematic

Robbins Fig. 29.17 depicts intact photoreceptor outer segments in an acute example.

The retina is already separated even while the outer segments remain.

Preserved outer segments provide a temporal clue—not a different detachment class.

Slide 25 · Chronic retinal detachment: Outer segments are lost

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Neurosensory retina

Outer segments absent in chronic detachment

Subretinal fluid / potential space

Retinal pigment epithelium

Choroid

Reading the schematic

The figure legend describes loss of photoreceptor outer segments in chronic detachment.

This chronic change can occur in both rhegmatogenous and nonrhegmatogenous disease.

Do not infer the mechanism from chronicity alone.

Slide 26 · Acute versus chronic structural findings

Acute illustrated example

Chronic illustrated example

Neurosensory retina separated

Photoreceptor outer segments intact

Textbook illustration uses break-associated example

Neurosensory retina separated

Photoreceptor outer segments missing

Finding is not specific for detachment mechanism

Slide 27 · Why duration modifies photoreceptor morphology

RPE is needed to maintain photoreceptor outer segments.

Persistent separation interrupts that interface.

Outer-segment loss is consequently a morphologic sign of chronicity.

This is a structural principle, not a quantitative prediction of visual recovery.

Slide 28 · Clinical warning symptoms

New flashes of light can accompany vitreoretinal traction.

A sudden increase in floaters requires prompt assessment.

A new shadow or curtain in the visual field suggests retinal involvement.

Absence of symptoms does not exclude a small peripheral detachment.

Slide 29 · Symptoms to urgent retinal examination

New flashes / floaters

Field shadow / curtain

Urgent dilated retinal examination

Identify tear, detachment, and macular involvement

Retinal detachment is treated as a medical emergency.

This is supplementary National Eye Institute clinical guidance.

Slide 30 · The dilated examination establishes anatomy

Inspect the retinal surface and periphery for breaks.

Determine whether neurosensory retina is elevated from RPE.

Assess coexisting traction, vascular disease, or choroidal lesions.

A symptom pattern alone cannot determine the mechanism.

Slide 31 · Imaging: What each assessment clarifies

Assessment

Main clinical question

Dilated fundus examination

Is there a retinal tear or detached retina?

Ocular ultrasonography

Where is the retina when the fundus view is inadequate?

Optical coherence tomography

How are retinal layers and the macular interface positioned?

Slide 32 · Morphology can suggest the mechanism

Rhegmatogenous pattern

Tractional / exudative patterns

Retinal break may be visible

Mobile or corrugated elevation may occur

Fluid enters from vitreous through break

Tractional: Membrane-related elevation

Serous: Smooth elevation from subretinal exudate

A break may be absent or hidden

Slide 33 · Do not overread the appearance

A retinal break can be difficult to identify when media are opaque.

An observed elevation is not sufficient to specify its cause.

Integrate the retinal surface, choroid, vascular findings, and vitreous state.

Slide 34 · The therapeutic objective in rhegmatogenous disease

Locate the retinal break

Reduce vitreoretinal traction

Reapproximate retina and RPE

Secure retinal break

Maintain retinal reattachment

The primary Robbins mechanism is mechanical relief of vitreous traction.

Clinical procedures vary with anatomy and detachment extent.

Slide 35 · Scleral buckling: Change the geometry of traction

External silicone element

Inward scleral indentation

Support beneath retinal break

Effective traction reduced

Retinal apposition can be restored

The buckle acts on the outer globe rather than replacing the vitreous.

Anatomic indentation is the mechanism emphasized.

Slide 36 · Vitrectomy addresses the vitreous component

Access vitreous cavity

Remove traction-causing vitreous

Treat retinal breaks as indicated

Support reattachment

Retina can be repositioned against RPE

Removal of vitreous as a complementary approach.

Other surgical details are supplementary clinical context.

Slide 37 · Retinal repair techniques: Their distinct roles

Technique

Core action

Clinical context

Scleral buckle

External scleral indentation

Relieves traction; Supports a break

Vitrectomy

Removes vitreous and traction

Repairs detachment from within the globe

Laser or cryopexy

Creates adhesion around retinal break

Treats tears; May accompany reattachment

Pneumatic retinopexy

Uses intraocular gas bubble

Selected detachments with appropriate breaks

Slide 38 · Retinal reattachment is not the only issue

Traction relief addresses the mechanical initiating factor.

Retinal break closure limits continued fluid access.

Proliferative vitreoretinopathy can complicate the repair by creating new membranes.

The approach is determined by retinal anatomy and associated pathology.

Slide 39 · Proliferative vitreoretinopathy: A complicating response

Rhegmatogenous detachment may be complicated by proliferative vitreoretinopathy (PVR).

Cell proliferation forms membranes on or below the retinal surface.

This is an adverse consequence of tissue injury and repair.

Slide 40 · Cells and membranes in PVR

Retinal detachment / injury

Retinal glial or RPE-cell response

Epiretinal or subretinal membranes

Distortion and additional traction may complicate repair

Glial cells and RPE cells as membrane-forming populations.

The compartment occupied by membranes is diagnostically informative.

Slide 41 · Epiretinal and subretinal membrane locations

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Neurosensory retina

Contracting surface membrane

Subretinal fluid / potential space

Retinal pigment epithelium

Choroid

Reading the schematic

Epiretinal: Membrane is positioned on the vitreous-facing retinal surface.

Subretinal: Membrane is located between neurosensory retina and RPE.

The same broad proliferative process can affect either compartment.

Slide 42 · Primary rhegmatogenous event versus PVR

Initiating detachment

PVR complication

Hyaloid traction creates a tear

Liquefied vitreous enters subretinal plane

Break drives initial fluid access

Glial or RPE-cell membranes develop

New tractional or structural obstacles appear

May complicate surgical reattachment

Slide 43 · Nonrhegmatogenous detachment: No tear is necessary

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Neurosensory retina

Protein-rich exudate

Retinal pigment epithelium

Choroid

Reading the schematic

Fluid accumulates under neurosensory retina without crossing a retinal break.

RPE injury can permit entry of fluid from choroidal circulation.

Exudative retinal vascular disorders are another recognized cause.

Slide 44 · An exudative mechanism begins outside the vitreous

Choroidal / vascular injury

RPE barrier dysfunction

Fluid escapes beneath retina

Serous neurosensory detachment

The source of subretinal fluid differs from rhegmatogenous disease.

Treating a hypothetical tear would not address the initiating event.

Slide 45 · Protein-rich fluid occupies the subretinal space

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Neurosensory retina

Protein-rich exudate

Retinal pigment epithelium

Choroid

Reading the schematic

Protein-rich exudate in nonrhegmatogenous detachment.

The fluid separates retina from RPE while retinal tissue may remain continuous.

Chronic outer-segment loss can also occur in this category.

Slide 46 · Severe hypertension: Choroidal vascular injury

Severe hypertension can damage retinal and choroidal vessels.

Choriocapillaris injury may damage overlying RPE.

Exudate can enter the retina–RPE potential space, causing detachment.

Slide 47 · Hypertensive choroidopathy to retinal detachment

Severe hypertension

Choriocapillaris damage

Overlying RPE injury

Subretinal exudate

Nonrhegmatogenous detachment

This mechanism is choroid/RPE-driven, not a vitreous tear.

Choroidal infarcts may be visible clinically as Elschnig spots.

Slide 48 · Retinal exudate versus subretinal exudate

Retinal vascular leakage

Choroidal / RPE injury

Leakage originates from retinal vessels

Exudate often accumulates in outer plexiform layer

May create a macular star in severe hypertension

Leakage originates across injured choroid–RPE interface

Fluid accumulates between RPE and neurosensory retina

Can produce exudative detachment

Slide 49 · Choroidal tumors: A different source of fluid

Choroidal tumors are cited among causes of nonrhegmatogenous retinal detachment.

The primary lesion lies beneath the retina.

Retinal separation is secondary to disease involving the choroid/RPE interface.

The detachment must not be mistaken for an isolated primary retinal tear.

Slide 50 · Fluid source: Vitreous versus choroid

Rhegmatogenous

Exudative

Requires full-thickness tear

Fluid arrives from liquefied vitreous

Posterior hyaloid traction commonly initiates the break

No tear required

Fluid follows vascular/RPE damage

Examples: Hypertension, choroidal tumor

Slide 51 · Tractional detachment: The retina is physically pulled

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Neurosensory retina

Contracting surface membrane

Subretinal fluid / potential space

Retinal pigment epithelium

Choroid

Reading the schematic

Fibrovascular membranes can contract against the retinal surface.

The resulting traction elevates retina away from RPE.

A tear may be absent initially.

Slide 52 · Diabetic microvascular injury leads to traction

Microvascular nonperfusion

Retinal hypoxia and VEGF

Surface neovascular membranes

Fibrosis / contraction

Tractional retinal detachment

Robbins specifically describes traction caused by scarring in proliferative diabetic retinopathy.

This is distinct from primary vitreous entry through a tear.

Slide 53 · VEGF connects ischemia and angiogenesis

Retinal micro-occlusion produces nonperfused tissue.

Ischemic retina upregulates VEGF.

New vessels grow in relation to the retinal surface and posterior hyaloid.

Neovascularization can develop a fibrous or glial scaffold.

Slide 54 · The internal limiting membrane is a key boundary

Schematic — tissue planes (not a clinical image)

Vitreous

Posterior hyaloid

Neurosensory retina

Contracting surface membrane

Subretinal fluid / potential space

Retinal pigment epithelium

Choroid

Reading the schematic

In proliferative diabetic retinopathy, new vessels extend beyond the retinal internal limiting membrane.

Neovascular membranes lie on the retinal surface or at the vitreoretinal interface.

Scarring in this location can act directly on retinal shape.

Slide 55 · Membrane contraction links neovascularization to detachment

Retinal surface neovascularization

Fibrous / glial stroma

Scar contraction

Retinal wrinkling and pull

Traction causes retinal elevation

Photoreceptor orientation may be disturbed, producing visual distortion.

Stronger traction can produce frank detachment.

Slide 56 · Traction may progress to a combined break-associated detachment

Initial tractional event

Secondary rhegmatogenous component

Membrane pulls retina away from RPE

No retinal break is required initially

Driving force is mechanical contraction

Severe traction tears neurosensory retina

Vitreous fluid can gain access through new break

Both tractional and rhegmatogenous mechanisms coexist

Slide 57 · Retinopathy of prematurity: Another tractional route

Immature peripheral retinal vessels may constrict in premature infants exposed to oxygen.

Peripheral retinal ischemia promotes VEGF and neovascularization.

Contracting peripheral membranes can drag the retina and macula.

Severe contraction may produce retinal detachment.

Slide 58 · Retinopathy of prematurity: The sequence

Immature retinal vasculature

Peripheral ischemia

Retinal angiogenesis

Membrane contraction

Macular displacement or detachment

This is a second disease model for traction-driven detachment.

The initiating problem is abnormal vascular development, not aging vitreous.

Slide 59 · Diabetes versus prematurity: Shared mechanics

Proliferative diabetic retinopathy

Retinopathy of prematurity

Microvascular damage/nonperfusion

VEGF-driven surface neovascularization

Membrane scarring exerts traction

Immature peripheral retinal circulation

Ischemia-driven neovascular membrane

Peripheral contraction can drag retina

Slide 60 · Four paths to one anatomical endpoint

Path

Starting lesion

Fluid/force

Break initially?

Rhegmatogenous

Vitreoretinal adhesion + tear

Vitreous fluid

Yes

Exudative

Vascular or RPE damage

Subretinal exudate

No

Tractional

Contracting membrane

Mechanical traction

Usually no

Combined traction + break

Severe membrane traction

Traction plus vitreous fluid

Becomes present

Slide 61 · Mechanism-first diagnostic reasoning

Detached neurosensory retina

Search for full-thickness break

Assess membrane traction

Assess choroid and exudation

Assign the dominant mechanism; Identify mixed disease

The absence of a visible break alone does not prove exudation.

Consider coexisting causes and limited visualization.

Slide 62 · Morphologic clues mapped to etiology

Finding

Reasoning implication

Full-thickness tear with subretinal fluid

Supports rhegmatogenous route

Protein-rich fluid without tear

Supports exudative nonrhegmatogenous route

Retinal elevation under contracting membrane

Supports tractional mechanism

Missing photoreceptor outer segments

Supports chronicity; Not a unique mechanism

Glial/RPE-cell surface membranes

Suggests proliferative vitreoretinopathy

Slide 63 · Case 1 — a focal hyaloid attachment

Aging vitreous has liquefied. Most of the posterior hyaloid has separated, but a small adhesion persists. A full-thickness retinal tear forms at that site.

What sequence explains retinal separation?

Tethered posterior hyaloid → retinal tear → liquefied vitreous enters subretinal space → rhegmatogenous detachment.

Slide 64 · Case 2 — subretinal fluid in severe hypertension

Severe hypertension is accompanied by choroidal microvascular injury and focal RPE damage. Subretinal exudate accumulates without an identified break.

Which detachment mechanism fits the findings?

Choriocapillaris/RPE injury allows subretinal fluid → exudative nonrhegmatogenous detachment.

Slide 65 · Case 3 — membrane-associated retinal elevation

A retina with proliferative diabetic neovascular membranes becomes wrinkled as the membranes scar and contract. Retinal elevation develops without a full-thickness break.

How should the detachment be classified at this stage?

Tractional, initially nonrhegmatogenous; Later a secondary tear could create a combined detachment.

Slide 66 · Case 4 — a chronic detached retina

A detached neurosensory retina has markedly shortened or absent photoreceptor outer segments. No original tear is identified in the limited specimen.

What can and cannot be inferred?

Chronicity is supported; The finding alone cannot distinguish rhegmatogenous from nonrhegmatogenous causes.

Slide 67 · Three commonly confused interfaces

Vitreous–retina

Retina–RPE

Posterior hyaloid contacts internal limiting membrane

PVD occurs here

Abnormal adhesions create traction

Photoreceptor outer segments face RPE

Retinal detachment occurs here

Exudate or vitreous fluid may separate layers

Slide 68 · Synthesis: Separate lesion, force, and endpoint

Initiating lesion

Break / exudation / traction

Subretinal separation

Retinal response

Classification + clinical consequence + repair challenge

The same anatomic endpoint has different upstream causes.

Photoreceptor change and membrane proliferation influence later tissue status.

Slide 69 · Core pathology conclusions

Retinal detachment is separation of neurosensory retina from RPE.

Rhegmatogenous detachment requires a full-thickness break and fluid entry from vitreous.

Exudative detachment follows vascular or RPE injury without a retinal break.

Tractional membranes may detach retina and may subsequently tear it.

Outer-segment loss indicates chronicity; PVR creates additional membrane pathology.

Slide 70 · Selected references

Robbins, Cotran & Kumar. Pathologic Basis of Disease. 11th ed. Elsevier; 2026. Chapter 29: The Eye, pp. 1198–1203; Fig. 29.17.

National Eye Institute. Retinal Detachment. Updated November 5, 2025. nei.nih.gov/eye-health-information/eye-conditions-and-diseases/retinal-detachment

National Eye Institute. Surgery for Retinal Detachment; Vitrectomy. Updated December 6, 2024.

American Academy of Ophthalmology. EyeWiki: Retinal Detachment. Accessed October 12, 2026. eyewiki.aao.org/Retinal_Detachment