Retinal folds are wrinkles or ridges in the thin neural tissue that lines the back of the eye, and they arise when mechanical forces push, pull, or compress the retina out of its normal flat configuration. They show up in a surprisingly wide range of situations, from a complication after eye surgery to a sign of shaken-baby trauma to a feature of rare inherited conditions in children. How a fold forms, which retinal layers it involves, and whether it threatens vision all depend on the underlying cause, making accurate diagnosis essential before any treatment decision.
What Makes the Retina Fold
The retina is a paper-thin sheet of neural tissue draped over a stiffer support structure: the choroid and sclera beneath it. When an outside force applies tangential stress to that sheet, it buckles, much the way a tablecloth wrinkles when you push it sideways. The retina is considerably less stiff than the choroid, so it folds more easily and at a finer scale. One analysis comparing epiretinal-membrane-induced retinal folds with choroidal folds found the average spacing between fold peaks was roughly 82 micrometers for retinal folds versus about 278 micrometers for choroidal folds, reflecting the retina’s lower resistance to deformation.1American Journal of Ophthalmology. Stiffness of Retinal and Choroidal Tissue: A Surface Wrinkling Analysis of Epiretinal Membranes and Choroidal Folds
The forces that create folds fall into a few broad categories. Traction from scar tissue or membranes can physically tug the retina into ridges. Compression from a gas bubble or buckle after surgery can push redundant tissue together. Loss of support from low eye pressure (hypotony) can let the retina sag and crumple. And developmental missteps during fetal vascular growth can leave the retina tethered in ways that distort it from birth. Each mechanism produces a fold with different characteristics, different layers involved, and different visual consequences.
Post-Surgical Folds
The single most commonly discussed clinical setting for retinal folds is surgery to repair a retinal detachment. When surgeons reattach the retina using techniques like scleral buckling, vitrectomy, or pneumatic retinopexy, the retina sometimes settles back into place with a wrinkle rather than lying perfectly flat. Macular folds after detachment surgery have been reported in up to about 3% of cases.2PubMed. Retinal folds following retinal detachment surgery That number sounds small, but for the individual patient a fold running through the center of vision can mean permanent distortion or reduced sharpness even though the retina is technically reattached.
Several risk factors raise the odds. A tamponading gas bubble used to hold the retina in place can push tissue into folds if it expands too much or if the patient’s head position is off. Large scleral buckle implants, detachments with a billowy or bullous shape, detachments that run through the fovea, and incomplete drainage of the fluid trapped under the retina all increase risk.2PubMed. Retinal folds following retinal detachment surgery The common thread is anything that leaves slack in the retinal tissue or pushes it unevenly during reattachment.
Folds after detachment repair are not all alike. Imaging reveals that some involve only the inner layers of the retina, some affect only the outer layers, and some run through the full thickness.3PubMed. Inner, outer, and full-thickness retinal folds after rhegmatogenous retinal detachment repair: A review In a classic full-thickness fold, all the neural layers separate from the pigment layer beneath and double over on themselves, with photoreceptors from adjacent folds oriented base to base. Inner retinal folds show corrugations only in the layers closest to the vitreous cavity, while outer retinal folds appear as dense lesions just above the pigment epithelium that may extend into the outer nuclear layer.3PubMed. Inner, outer, and full-thickness retinal folds after rhegmatogenous retinal detachment repair: A review These distinctions matter because they affect both the visual impact and the potential for treatment.
Trauma and Abusive Head Injury
Retinal folds carry a specific and serious significance in pediatric medicine. In infants and young children who have suffered abusive head trauma, perimacular folds are a recognized finding during eye examination. These folds form when violent shaking or impact causes the vitreous gel inside the eye to pull on the retina with sudden, intense traction. Pathology studies of such cases have found condensed vitreous attached to the peaks of the retinal folds, along with detachment of the retina’s inner limiting membrane and splitting of the retinal layers at the macula.4Retina. Pathology of Perimacular Folds Due to Vitreoretinal Traction in Abusive Head Trauma
The presence of perimacular folds in an infant who is too young to have experienced accidental injury is considered highly suspicious for non-accidental trauma. While other causes of retinal folds exist, the pattern of vitreoretinal traction folds concentrated around the macula, combined with retinal hemorrhages and other signs, forms a constellation that forensic ophthalmologists look for. These folds tend to be devastating for vision because they sit right at the center of the visual field, and the underlying brain injury is the primary life-threatening concern.
Congenital and Developmental Causes
Some retinal folds are present at birth or develop in infancy because the eye’s vascular system did not form correctly. The retina’s blood supply develops through a carefully choreographed process during fetal life, and genetic mutations or premature birth can derail it.
Persistent fetal vasculature is one such condition. Normally the fetal blood vessels inside the eye regress before birth, but when they fail to do so, the leftover tissue can pull on the retina and create folds or even a falciform retinal detachment, where the retina is dragged into a tent-like configuration. Persistent fetal vasculature is responsible for an estimated 5% of childhood blindness in western countries.5Asia-Pacific Journal of Ophthalmology. Persistent Fetal Vasculature Imaging of these eyes with optical coherence tomography can reveal the retinal folds and the remnant fetal vessels causing them.6PubMed Central. Optical coherence tomography findings of falciform retinal detachment complicated with persistent fetal vasculature
A group of rare inherited conditions shares a similar story. Familial exudative vitreoretinopathy (FEVR), Norrie disease, and persistent fetal vascular syndrome all stem from disruptions to the signaling pathway that guides retinal blood vessel growth. Mutations in genes such as NDP, FZD4, TSPAN12, and LRP5 impair retinal endothelial cell function, leading to incomplete or abnormal vascular development and, in many cases, retinal folds, traction, and detachment.7PubMed. Mechanisms Underlying Rare Inherited Pediatric Retinal Vascular Diseases: FEVR, Norrie Disease, Persistent Fetal Vascular Syndrome These conditions are clinically distinct from one another but share that common vascular thread.
Retinopathy of prematurity is another major cause in the pediatric population. Premature infants whose retinal vessels have not yet finished growing are vulnerable to abnormal vessel proliferation, scar formation, and traction that can pull the retina into folds or detach it entirely. In the landmark CRYO-ROP study, roughly 30% of treated eyes still progressed to a macular fold or retinal detachment despite cryotherapy, underscoring how aggressive the condition can be.
Inflammatory and Infectious Causes
Infections inside the eye can generate scar tissue and membranes that pull the retina into folds. Ocular toxocariasis, caused by the larvae of a common roundworm, is a classic example. In affected eyes, the parasite typically triggers a mass of inflammatory tissue in the peripheral retina, and fibrous bands stretch from that mass toward the back of the eye. Those bands produce traction that can fold the retina or partially detach it.8PubMed. Echographic characteristics of ocular toxocariasis The traction retinal fold or detachment running from the posterior pole to the peripheral mass is so characteristic that ultrasound showing this pattern can help clinch the diagnosis even before the parasite is confirmed.
Retinitis from other causes, including viral infections, can also produce outer retinal folds. In eyes with active retinitis, optical coherence tomography sometimes reveals vertical, dense lesions in the outer retina involving the photoreceptor and outer nuclear layers.9PubMed Central. Clinical and imaging characteristics of outer retinal folds in eyes with retinitis These outer retinal folds likely represent localized swelling and structural distortion from inflammation rather than the mechanical traction seen in toxocariasis or post-surgical cases, but they can look similar on a basic eye exam.
Low Eye Pressure and Retinal Redundancy
The eye maintains its shape partly through internal pressure. When that pressure drops well below normal, a condition called hypotony, the wall of the eye starts to collapse inward. The retina and choroid, which were taut against a firm sphere, suddenly have more surface area than the shrunken globe can accommodate, and they buckle into folds. In hypotony maculopathy, the scleral wall collapses and causes secondary redundancy of both the retina and choroid.10PubMed Central. Hypotony Maculopathy: Clinical Presentation and Therapeutic Methods
Hypotony can result from over-filtration after glaucoma surgery, a leaking wound, inflammation that shuts down the fluid-producing cells inside the eye, or certain medications. The folds it creates tend to involve both the retina and choroid together, producing chorioretinal folds rather than isolated retinal folds. Vision can be significantly affected if folds cross the macula, and the visual loss may not fully reverse even after pressure is restored, especially if the folds have been present for a long time.
How Retinal Folds Are Diagnosed
A dilated eye exam can reveal obvious retinal folds, but optical coherence tomography (OCT) has transformed the way clinicians evaluate them. OCT produces cross-sectional images of the retina with micrometer-level resolution, allowing a doctor to see exactly which layers are folded, whether subretinal fluid is present, and whether any membranes or traction bands are attached.
The distinction between inner, outer, and full-thickness folds is essentially an OCT-based classification. Inner retinal folds show up as ripples in the nerve fiber layer and ganglion cell layer while the outer retina stays relatively flat. Outer retinal folds appear as dense bumps sitting above the pigment epithelium.9PubMed Central. Clinical and imaging characteristics of outer retinal folds in eyes with retinitis Full-thickness folds show the entire retina buckling away from the underlying pigment layer.3PubMed. Inner, outer, and full-thickness retinal folds after rhegmatogenous retinal detachment repair: A review Without OCT, these would all look like vaguely similar lines on a clinical exam.
Epiretinal membranes, thin sheets of scar-like tissue that grow on the retinal surface and contract, are one of the more common causes of retinal surface wrinkling. OCT can visualize these membranes directly, measuring their thickness and showing whether they are tightly stuck to the retina or tethered at only a few points.11Ophthalmology. Characterization of epiretinal membranes using optical coherence tomography That information matters for surgical planning: a membrane with a few focal attachment points may be easier to peel than one that is globally adherent across the entire macular surface.
Retinal Folds Versus Choroidal Folds
Clinicians draw a sharp line between retinal folds and choroidal folds, even though both involve wrinkled tissue at the back of the eye. Choroidal folds are undulations in the choroid, Bruch’s membrane, and the pigment epithelium, sometimes extending into the overlying retina. They tend to be broader and more widely spaced than pure retinal folds because the choroid is stiffer.1American Journal of Ophthalmology. Stiffness of Retinal and Choroidal Tissue: A Surface Wrinkling Analysis of Epiretinal Membranes and Choroidal Folds The causes are different too: choroidal folds often point to orbital tumors, thyroid eye disease, posterior scleritis, or hypotony, whereas retinal folds more commonly reflect traction from membranes, post-surgical changes, or developmental vascular problems.
Modern retinal imaging has improved the ability to tell these apart and to catch complications. Chronic chorioretinal folds can, over time, lead to the development of abnormal new blood vessels (choroidal neovascularization), making long-term monitoring important even when the folds themselves seem stable.12PubMed Central. Recognition, Diagnosis and Treatment of Chorioretinal Folds: Current Perspectives Folds that initially seem like a cosmetic concern on imaging can become sight-threatening if new vessels grow and leak.
Treatment Options
Treatment for retinal folds depends entirely on the cause, the layers involved, and whether the fold is affecting vision. There is no single “fix” that works across the board.
For post-surgical folds, prevention is the first line of defense. Correct head positioning after surgery helps the retina settle flat rather than crumpled. In pneumatic retinopexy, for example, specific positioning maneuvers can reduce subretinal fluid and minimize slack in the retina. One technique, called the mini-steamroll, involves ten minutes of face-down positioning followed by positioning toward the retinal break, and has shown promise in rapidly reducing subretinal fluid in certain detachment configurations.13Retina. The Mini-Steamroll: An Abbreviated Variation of the Steamroller Maneuver After Pneumatic Retinopexy for Rhegmatogenous Retinal Detachment Avoiding modifiable risk factors, such as overfilling the gas bubble or leaving excessive subretinal fluid at the end of surgery, also helps.2PubMed. Retinal folds following retinal detachment surgery
When a fold has already formed and is affecting central vision, surgical correction is sometimes attempted, but reports of success are limited. Very few published cases describe a good outcome from surgically flattening a post-operative retinal fold, and the decision about whether and when to intervene remains controversial among retinal specialists.2PubMed. Retinal folds following retinal detachment surgery The concern is that re-operating on a recently reattached retina introduces new risks of detachment, proliferative scarring, and additional folds.
For epiretinal membranes causing surface wrinkling, surgical peeling of the membrane (membrane peel or vitrectomy with membrane removal) is the standard approach when vision is significantly affected. The surgery involves entering the vitreous cavity, grasping the edge of the membrane, and carefully separating it from the retinal surface. Once the contractile membrane is removed, the underlying retinal folds often flatten over weeks to months, though some distortion may persist.
In hypotony-related folds, the treatment targets the low pressure rather than the folds themselves. Repairing a wound leak, revising an over-draining glaucoma surgery, or treating the underlying inflammation to restore normal fluid production can allow the eye to re-inflate and the folds to settle. Prompt correction matters because chronic folds may cause lasting structural changes.
For congenital conditions like persistent fetal vasculature, early surgical intervention in infancy aims to remove the remnant fetal tissue and relieve traction before the retina is permanently damaged. The visual prognosis depends heavily on how much retinal involvement existed before surgery. In severe cases, the goal may be preserving the eye itself rather than restoring useful vision.
Why Some Folds Matter More Than Others
Not every retinal fold demands treatment. A small fold in the peripheral retina after detachment surgery, well away from the macula, may cause no symptoms at all and can simply be monitored. A full-thickness fold running through the fovea, on the other hand, can severely distort central vision and make reading or recognizing faces difficult.
The layer involved also influences outcomes. Outer retinal folds, which disrupt the photoreceptor layer, tend to have a greater impact on visual acuity than inner retinal folds of the same size, because the photoreceptors are where light is actually converted into neural signals. Inner retinal folds may scatter light or create mild distortion but often have a milder effect on sharpness. Full-thickness folds combine both problems and are generally the most visually significant.
Timing matters as well. A fold identified within a day or two of surgery, before the retina has fully re-adhered, may still be amenable to repositioning through head posture changes or gentle manipulation. A fold that has been present for months tends to become fixed as the tissue remodels around it, making correction far more difficult.
Emerging Imaging and Artificial Intelligence
OCT is already indispensable for evaluating retinal folds, but the broader trend in retinal imaging is toward automated analysis. Deep learning systems have been trained to classify OCT images into categories like drusen, diabetic macular edema, and choroidal neovascularization with high accuracy.14SvedbergOpen. RetinaFoldNet: An Intelligent Deep Learning Framework for Automated OCT-Based Retinal Disease Diagnosis These tools do not yet specifically classify retinal folds as a standalone category, but the underlying technology is the same: algorithms that learn to recognize structural patterns in cross-sectional retinal images. As training datasets expand to include more examples of folds, automated screening could eventually flag subtle folds that a clinician might overlook during a busy clinic session, particularly in post-operative surveillance imaging.
For now, the interpretation of retinal folds still relies heavily on clinical judgment. A fold’s location, the layers it involves, its relationship to any traction bands or membranes, and the clinical context (post-surgical versus congenital versus traumatic) all feed into the assessment. No algorithm yet integrates all of that context the way an experienced retinal specialist does, but the gap is narrowing.