Retina Companion Note
Tractional Retinal Detachment
Mechanism, morphology, macular assessment and management principles
Tractional retinal detachment occurs when pathological tissue at the vitreoretinal interface contracts and mechanically pulls the neurosensory retina away from the retinal pigment epithelium. This companion note explains how to recognise pure TRD, identify an added rhegmatogenous component and decide when intervention is required.
Three Mechanisms of Retinal Detachment
A retinal detachment is a separation of the neurosensory retina from the underlying retinal pigment epithelium. The mechanism determines the basic clinical problem and guides management.
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| Mechanism | Primary problem | Core sequence |
|---|---|---|
| Rhegmatogenous RD | A full-thickness retinal break allows fluid to enter the subretinal space. | Break → subretinal fluid → detachment |
| Tractional RD | Pathological tissue mechanically pulls the retina away from the RPE. | Traction → retinal elevation |
| Exudative or Serous RD | Fluid accumulates beneath the retina because of another underlying disease process. | Underlying disease → subretinal fluid |
These mechanisms may coexist. A pure TRD may develop a retinal break and become a combined TRD/RRD.
What Is a Pure TRD?
A tractional retinal detachment occurs when pathological tissue at the vitreoretinal interface contracts and mechanically pulls the neurosensory retina away from the retinal pigment epithelium.
The word causative is important. A retinal break may develop in an eye that already has traction. Once the break contributes to the detachment, the mechanism becomes a combined TRD/RRD.
Traction does not always produce a true retinal detachment. It may cause retinal wrinkling, fixed folds, vascular displacement or macular distortion without creating a subretinal space.
Do Not Confuse
Tractional retinoschisis and true TRD
- Tractional retinoschisis The separation occurs within the retinal layers.
- True tractional retinal detachment The full neurosensory retina separates from the RPE, creating a subretinal space.
- The two findings are not obligatory sequential stages. They may occur independently or coexist in the same eye. [4] [5]
How Traction Develops
Proliferative diabetic retinopathy provides the clearest clinical model. The process begins with retinal ischaemia and ends when contracting fibrovascular tissue pulls the retina away from the RPE.
Retinal ischaemia drives proliferation
Extensive retinal non-perfusion promotes neovascularisation. The new vessels grow with fibrous tissue, producing fibrovascular proliferation at the vitreoretinal interface.
The posterior vitreous provides a scaffold
The posterior cortical vitreous, or posterior hyaloid, provides an important surface along which neovascular and fibrovascular tissue can grow.
Anteroposterior traction
Persistent vitreoretinal attachments pull the retina anteriorly at fixed points of fibrovascular adhesion.
Tangential traction
Membranes contract along the retinal surface, producing folds, puckering, vascular displacement and macular distortion.
Sequence to remember
Retinal ischaemia → neovascular and fibrovascular proliferation → growth along the vitreoretinal interface → fibrosis and contraction → retinal distortion or detachment
Clinical Pearl
TRD is the final mechanical result of contracting tissue that remains attached to the retina.
Causes of Tractional Retinal Detachment
TRD is a mechanism rather than a single disease. Different disorders can produce contracting tissue at the vitreoretinal interface and ultimately pull the retina away from the RPE.
Adults
- Proliferative diabetic retinopathy
- Proliferative sickle-cell retinopathy
- Eales disease
- Rarely, severe ischaemic retinal-vein occlusion
- PVR-associated complex or mixed retinal detachment
Children
- Retinopathy of prematurity
- Familial exudative vitreoretinopathy
- Persistent fetal vasculature
PVR is a different fibrotic pathway
Proliferative vitreoretinopathy is an abnormal wound-healing response, usually associated with retinal breaks, retinal surgery or trauma. It commonly produces fixed folds, retinal shortening and mixed tractional-rhegmatogenous disease. [1] [2]
Important
PDR is the most common cause of tractional retinal detachment in adults.
What Traction Does to the Retina
In a classical pure TRD, the retina remains fixed at points of strong vitreoretinal or fibrovascular attachment. It therefore does not usually rise as one freely mobile sheet.
Tethered elevation
The retina is held at fixed tractional attachment points rather than being lifted only by freely spreading subretinal fluid.
Tented or peaked contour
The retinal elevation may be most pronounced at the sites of strongest vitreoretinal adhesion.
Relatively concave shape
The retina is often concave between fixed traction points, unlike the more freely convex or bullous configuration of many rhegmatogenous detachments.
Reduced mobility
The detached retina is usually less mobile because it remains tethered by fibrovascular membranes.
Surface distortion
Tangential contraction may produce fixed folds, retinal puckering, vascular straightening or displacement and macular distortion.
Fibrovascular tissue may be visible as membranes, bands or plaques. When the posterior pole is involved, the patient may develop metamorphopsia even before the fovea becomes detached. [3] [4]
Wisdom Pearl
A pure TRD is shaped by its fixed tractional attachment points.
Relationship to the Macula
The relationship of a TRD to the macula is one of the most important factors guiding observation, imaging and surgery.
Extramacular TRD
The detachment does not involve the fovea. A stable extramacular TRD may sometimes be observed with reliable follow-up.
Macula-threatening TRD
The tractional elevation is approaching or progressing toward the macula and places central vision at risk.
Macula-involving TRD
The foveal neurosensory retina is detached from the RPE.
No universal distance cutoff
There is no single numerical distance that defines a macula-threatening TRD. Assessment depends on the configuration, direction of progression and comparison with previous examination or imaging. [7]
Important
Classify the retinal anatomy, not the visual acuity. Good central vision does not exclude progression toward the fovea, and reduced vision does not necessarily mean that the fovea is detached.
Pure TRD or Combined TRD/RRD?
The important clinical question is whether traction alone still explains the entire detachment. A change in retinal configuration may indicate that a retinal break has added a rhegmatogenous component.
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| Feature | Pure TRD | Combined TRD/RRD |
|---|---|---|
| Main mechanism | Mechanical traction without a causative retinal break. | Traction together with a full-thickness retinal break. |
| Configuration | Often tethered, tented and relatively concave. | May become more convex or bullous. |
| Extent | Usually remains related to visible tractional attachments. | May extend beyond the area explained by visible traction. |
| Mobility | Usually relatively limited. | May become more mobile, although this is not a defining sign. |
| Retinal break | No causative full-thickness break. | A break is present but may be hidden beneath a membrane, fold or haemorrhage. |
Central Diagnostic Clue
The visible traction does not adequately explain the extent or configuration of the detachment.
Suspect a rhegmatogenous component when a localised TRD becomes more extensive, more convex or bullous, or extends toward the peripheral retina or ora serrata. The retinal break may only become visible during surgery. [4] [6]
Exam Pearl
No break seen does not prove that the detachment is purely tractional.
Clinical Assessment
Clinical assessment should define the extent of traction, its relationship to the macula and whether the anatomy is stable or progressing.
Symptoms
An extramacular TRD may cause little or no visual disturbance. As traction approaches or affects the macula, the patient may develop metamorphopsia, progressive central visual loss or distortion.
A sudden marked reduction in vision may be caused by vitreous haemorrhage rather than sudden foveal detachment.
Photopsias are less typical of a slowly progressive pure TRD. New flashes or a sudden field defect should raise concern for an acute vitreoretinal event or an added rhegmatogenous component.
Fundus Examination
- Location and extent of the detachment
- Relationship to the macula
- Fibrovascular proliferation and traction points
- Retinal folds and vascular distortion
- Vitreous or preretinal haemorrhage
- Active neovascularisation and previous PRP
- Any visible or suspected retinal break
Causes of Tractional Retinal Detachment
TRD is a mechanism rather than a single disease. Different disorders can produce contracting tissue at the vitreoretinal interface and ultimately pull the retina away from the RPE.
Adults
- Proliferative diabetic retinopathy
- Proliferative sickle-cell retinopathy
- Eales disease
- Rarely, severe ischaemic retinal-vein occlusion
- PVR-associated complex or mixed retinal detachment
Children
- Retinopathy of prematurity
- Familial exudative vitreoretinopathy
- Persistent fetal vasculature
PVR is a different fibrotic pathway
Proliferative vitreoretinopathy is an abnormal wound-healing response, usually associated with retinal breaks, retinal surgery or trauma. It commonly produces fixed folds, retinal shortening and mixed tractional-rhegmatogenous disease. [1] [2]
Important
PDR is the most common cause of tractional retinal detachment in adults.
Imaging According to the Clinical Question
Imaging should be selected according to the anatomy that needs to be defined. No single investigation answers every question in TRD.
OCT
- Determines whether the fovea is attached
- Shows macular distortion and tractional elevation
- Distinguishes tractional retinoschisis from true TRD
- Documents progression on serial scans
- Shows associated oedema or outer-retinal damage
B-Scan Ultrasound
B-scan is most useful when dense vitreous haemorrhage or another media opacity prevents adequate fundus examination.
It may demonstrate retinal elevation, vitreoretinal membranes and persistent tractional attachments.
Fluorescein Angiography
Fluorescein angiography is not required simply to prove that traction exists.
Its main role is to assess retinal non-perfusion, active neovascularisation, leakage and residual untreated ischaemic retina.
OCT Angiography
OCT angiography may demonstrate non-perfusion and neovascular complexes, but it remains an adjunct rather than an essential test for confirming established TRD.
Clinical Pearl
OCT defines macular anatomy, B-scan assesses the obscured posterior segment, and angiography evaluates the underlying proliferative disease.
A Practical Diagnostic Framework
Diagnosis should not depend on one isolated sign. Define the anatomy, determine progression and confirm that the proposed mechanism explains the complete detachment.
-
1
Is there a true retinal detachment?
Distinguish surface distortion or tractional retinoschisis from separation of the neurosensory retina from the RPE.
-
2
Is the fovea attached, threatened or involved?
Base this on retinal anatomy rather than visual acuity alone.
-
3
Is the anatomy stable or progressing?
Compare with previous examination, photographs or serial OCT whenever available.
-
4
Does visible traction explain the entire detachment?
Look for a mismatch between the visible fibrovascular traction and the extent, shape or mobility of the detached retina.
Clinical Action
If visible traction does not explain the complete detachment, actively look for an added rhegmatogenous mechanism.
Management Framework
Management is guided by the relationship to the macula, documented progression, the underlying mechanism and the realistic potential for useful vision.
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| Clinical Situation | General Approach |
|---|---|
| Stable extramacular TRD | Observation may be appropriate when the macula remains uninvolved, the anatomy is stable and reliable follow-up is possible. |
| Progressive macula-threatening TRD | Surgery is generally favoured because documented progression places central vision at risk, even when visual acuity remains good. |
| Macula-involving TRD | Vitrectomy is generally considered when meaningful visual potential remains. |
| Combined TRD/RRD | Ordinarily requires surgical management because both the traction and retinal-break components must be addressed. |
A stable extramacular detachment can sometimes be followed with serial examination, photography or OCT. Documented progression toward the macula generally shifts management toward surgery.
Chronicity may reduce the expected visual recovery, but it is not an automatic contraindication to surgery. [2] [7]
Important
Visual acuity alone should not determine management. Retinal anatomy, progression and macular involvement must be assessed separately.
PRP, Anti-VEGF and Established Traction
PRP and anti-VEGF treatment help control the proliferative drive of diabetic retinopathy, but neither treatment mechanically releases an established tractional detachment.
Panretinal photocoagulation
PRP reduces the ischaemic stimulus for neovascularisation. It may help control active proliferative disease, but it does not remove existing fibrovascular traction.
Anti-VEGF
Anti-VEGF causes regression of active neovascular tissue. It may be used to treat PDR or as a preoperative adjunct, but it does not mechanically detach adherent fibrovascular membranes from the retina.
Anti-VEGF Before Vitrectomy
Preoperative anti-VEGF may reduce the vascularity of fibrovascular membranes and make diabetic vitrectomy safer or more controlled.
- Improved operative visualisation
- Reduced intraoperative bleeding
- Potentially fewer iatrogenic retinal breaks
- Reduced early postoperative vitreous haemorrhage
These benefits are supported by prospective surgical evidence. [11]
Do Not Confuse
Anti-VEGF crunch
Anti-VEGF crunch describes rapid development or progression of TRD after an anti-VEGF injection in an eye with proliferative retinopathy.
Greater caution is required when there is:
- Severe active PDR
- Extensive fibrovascular proliferation
- Broad or complex fibrotic membranes
- Marked pre-existing traction
The literature does not provide a universally accepted diagnostic definition or a reliable population incidence. Reported worsening may occur over days to several weeks. [9] [10]
Balanced Interpretation
Anti-VEGF does not generally increase TRD risk in ordinary trial-eligible PDR populations, but rapid tractional worsening can occur in selected eyes with advanced pre-existing fibrovascular disease. [8]
When anti-VEGF is used in a high-risk tractional eye, surgery should already be planned and avoidable delay should be minimised. There is no universal injection-to-surgery interval.
What Is Not Automatic in Every TRD Operation?
The extent of surgery depends on the anatomy. Several manoeuvres may be required in complex cases, but they are not compulsory in every pure TRD.
Complete posterior vitreous separation
The posterior hyaloid should not be forcibly separated from every area of strong fibrovascular adhesion.
Removal of every membrane fragment
A small residual island may be left when it no longer exerts traction and removal would increase the risk of bleeding or retinal injury.
Direct subretinal-fluid drainage
In a pure TRD without a retinal break, subretinal fluid may absorb gradually after the traction has been released.
Retinopexy and internal tamponade
Gas or silicone oil is not required simply because a tractional detachment was present.
Retinotomy or retinectomy
These are selected manoeuvres for complex anatomy rather than routine steps in every TRD operation.
When drainage, retinopexy or tamponade becomes more relevant
These manoeuvres are more likely to be required when there is a pre-existing or iatrogenic retinal break, a planned retinotomy or retinectomy, residual traction or inadequate retinal apposition.
Retinotomy and retinectomy
A retinotomy is a deliberate retinal opening, for example to drain subretinal fluid or gain access beneath the retina.
A retinectomy removes a portion of shortened, stiff retina that cannot flatten despite adequate traction release. [2]
Surgical Principle
The operation should be tailored to the mechanism and residual anatomy, rather than applying every manoeuvre routinely.
Principles of Vitrectomy in TRD Surgery
The purpose of surgery is to remove the forces that are pulling the retina away from the RPE. The surgeon is primarily releasing traction, not simply pushing the retina back into place.
Relieve anteroposterior vitreous traction
Remove free vitreous and release the forces transmitted through persistent posterior-hyaloid attachments.
Segment connected fibrovascular membranes
Divide membrane bridges so that traction is no longer transmitted across one continuous fibrovascular network.
Delaminate persistent tractional tissue
Separate membranes that continue to elevate or distort the retina after segmentation.
Identify and manage retinal breaks
Look for pre-existing or iatrogenic breaks after traction has been released and treat the rhegmatogenous component when present.
Truncation, Segmentation and Delamination
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| Term | What It Means | Mechanical Purpose |
|---|---|---|
| Truncation | Cutting the attached posterior hyaloid around a fibrovascular adhesion. | Stops vitreous traction from being transmitted to the retinal attachment. |
| Segmentation | Dividing connected fibrovascular membrane bridges into smaller islands. | Interrupts the spread of traction across the membrane network. |
| Delamination | Separating persistent fibrovascular tissue from the retinal surface. | Removes residual traction that continues to elevate or distort the retina. |
Surgical Principle
Truncation releases vitreous pull, segmentation breaks the membrane network, and delamination removes persistent retinal-surface traction.
Retinal Breaks Change the Operation
A retinal break may already be present in a combined TRD/RRD or may be created during membrane dissection.
When a break is present, traction around it must be relieved and the rhegmatogenous component may require subretinal-fluid drainage, retinopexy and internal tamponade. [2] [7]
Prognosis and Counselling
After TRD surgery, counselling should separate three different outcomes. Anatomical success does not automatically mean good visual recovery.
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| Outcome | What It Means | Counselling Point |
|---|---|---|
| Anatomical success | Relief of traction and successful retinal reattachment. | Modern vitrectomy may achieve retinal reattachment even in complex disease, but reattachment alone does not define the final vision. |
| Visual recovery | Improvement or preservation of useful visual function. | The strongest practical predictor is the preoperative visual acuity, together with the preoperative condition of the macula. |
| Long-term disease control | Continued control of the underlying proliferative retinal disease. | Successful surgery does not remove the need for systemic disease control, retinal surveillance and further treatment when indicated. |
Why Vision May Remain Limited
Macular ischaemia
Reattachment cannot restore vision already limited by inadequate macular perfusion.
Longstanding macular detachment
Chronic separation may produce irreversible outer-retinal and photoreceptor damage.
Diabetic macular oedema
Persistent or recurrent oedema may continue to limit central vision after anatomical reattachment.
Residual macular distortion
Chronic traction, retinal folds or structural distortion may limit visual quality even when the retina is attached.
Advanced ocular disease
Neovascular glaucoma, optic-nerve damage or other complex retinal pathology may restrict the final visual potential.
Chronic and combined detachments
Chronicity generally worsens visual prognosis, but it is not an automatic contraindication to surgery. Combined TRD/RRD is more complex than pure TRD, but meaningful anatomical and visual improvement may still be possible in appropriately selected eyes. [2] [6]
Key Counselling Message
The retina may be reattached anatomically, but the final vision depends largely on the condition and function of the macula before surgery.
Take-Home Framework
The following principles provide a practical way to understand, classify and manage tractional retinal detachment.
-
1
Confirm that a true detachment exists
Retinal wrinkling, surface distortion and tractional retinoschisis are not equivalent to separation of the neurosensory retina from the RPE.
-
2
Define the relationship to the macula
Classify the detachment as extramacular, macula-threatening or macula-involving using retinal anatomy rather than visual acuity alone.
-
3
Look for progression
Serial examination, photography and OCT may be more informative than the appearance at one isolated visit.
-
4
Decide whether traction explains the entire detachment
A more extensive, convex or bullous configuration should raise suspicion for a hidden retinal break and combined TRD/RRD.
-
5
Match treatment to the anatomy
Stable extramacular disease may be observed, whereas progressive macula-threatening, macula-involving or combined detachments generally favour surgery.
-
6
Remember the central surgical goal
Vitrectomy succeeds by releasing traction. Drainage, retinopexy, tamponade and retinectomy are added only when the residual anatomy requires them.
Final Principle
In TRD, first understand the mechanical forces, then define the macular anatomy and progression, and finally choose treatment according to the mechanism that remains.
References
- 1. Solinski MA, et al. Tractional retinal detachment. Disease-a-Month. 2021;67(5):101142. doi:10.1016/j.disamonth.2021.101142
- 2. Stewart MW, Browning DJ, Landers MB. Current management of diabetic tractional retinal detachments. Indian Journal of Ophthalmology. 2018;66(12):1751–1762. doi:10.4103/ijo.IJO_1217_18
- 3. Michels RG. Proliferative diabetic retinopathy: pathophysiology of extraretinal complications and principles of vitreous surgery. Retina. 1981;1(1):1–17. PMID:15633404
- 4. Lincoff H, et al. Tractional elevations of the retina in proliferative diabetic retinopathy. American Journal of Ophthalmology. 1992;113(3):235–242. doi:10.1016/S0002-9394(14)71573-9
- 5. Imai M, et al. Optical coherence tomography of tractional macular elevations in proliferative diabetic retinopathy. American Journal of Ophthalmology. 2001;132(1):81–84. doi:10.1016/S0002-9394(01)00910-2
- 6. Yang CM, et al. Surgical treatment of combined tractional and rhegmatogenous retinal detachment in proliferative diabetic retinopathy. Canadian Journal of Ophthalmology. 2008;43(2):192–198. doi:10.3129/i08-007
- 7. Lim JI, et al.; American Academy of Ophthalmology Preferred Practice Pattern Committee. Diabetic Retinopathy Preferred Practice Pattern. Ophthalmology. 2025;132(4):P75–P162. doi:10.1016/j.ophtha.2024.12.020
- 8. Bressler NM, et al. Anti-VEGF therapy and the risk of traction retinal detachment in eyes with proliferative diabetic retinopathy: a pooled analysis of five DRCR Retina Network trials. Retina. 2020;40(6):1021–1028. doi:10.1097/IAE.0000000000002633
- 9. Arevalo JF, et al. Tractional retinal detachment following intravitreal bevacizumab in patients with severe proliferative diabetic retinopathy. British Journal of Ophthalmology. 2008;92(2):213–216. doi:10.1136/bjo.2007.127142
- 10. Tan Y, et al. Anti-VEGF crunch syndrome in proliferative diabetic retinopathy: a review. Survey of Ophthalmology. 2021;66(6):926–932. doi:10.1016/j.survophthal.2021.03.001
- 11. Arevalo JF, et al. Preoperative bevacizumab for tractional retinal detachment in proliferative diabetic retinopathy: a prospective randomized clinical trial. American Journal of Ophthalmology. 2019;207:279–287. doi:10.1016/j.ajo.2019.05.007
