Retinal Detachment

Overview

Retinal detachment is a separation of the neurosensory retina from the retinal pigment epithelium.¹ Rhegmatogenous retinal detachment (RRD) is a potentially blinding separation caused by fluid passing from the vitreous cavity into the subretinal space through one or more retinal breaks, holes, or tears.² This condition represents an ophthalmologic emergency requiring immediate surgical treatment.³

While most RRDs can be repaired surgically with one operation, some visual loss often results, especially if the macula has been detached.² A small fraction of RRDs require multiple surgeries with significant morbidity, including permanent severe visual loss.² Prevention through early diagnosis of retinal tears and prophylactic outpatient retinopexy is ideal, as this procedure is highly successful in sealing retinal breaks and usually uncomplicated.²

Epidemiology & Risk Factors

Retinal detachment is relatively rare, though it poses a significant threat to vision with macular involvement.¹ Most retinal detachments are rhegmatogenous in nature.¹

Main risk factors for rhegmatogenous retinal detachment include retinal tears, myopia, and previous cataract surgery.³ Myopic patients demonstrate increased risk of pseudophakic retinal detachment.⁴ Additional risk factors for pseudophakic retinal detachment include vitreous loss at the time of cataract surgery and Nd:YAG posterior capsulotomy.⁴

Most RRDs are idiopathic, though traumatic RRDs can occur in hazardous sports and occupations.² The incidence of pseudophakic retinal detachment following current surgical techniques of cataract extraction, including extracapsular cataract extraction by nuclear expression and phacoemulsification, is lower than that found after intracapsular cataract extraction.⁴

Pathophysiology

In rhegmatogenous retinal detachment, fluid passes from the vitreous cavity into the subretinal space through retinal breaks, holes, or tears, causing separation of the neurosensory retina from the retinal pigment epithelium.²

The subretinal space between the photoreceptors and the retinal pigment epithelium is the remnant of the embryonic optic vesicle.⁵ In the developed eye, this space is of minimal size but can reopen under pathological conditions that disrupt the integrity of the blood-retinal barrier.⁵

In exudative retinal detachment, fluid collects in the subretinal space when inflammatory, infectious, infiltrative, neoplastic, vascular, and degenerative conditions cause blood-retinal barrier breakdown.⁵ This mechanism differs from rhegmatogenous detachment, which requires a retinal break.

Posterior vitreous detachment is an important precursor to retinal tear formation, which can subsequently progress to retinal detachment if untreated.³

Clinical Presentation

Patients with retinal detachment typically present with symptoms related to posterior vitreous detachment and retinal tears. The interval between retinal tears and detachment of the retina is often long enough for laser retinopexy, though the importance of retinal tear symptoms and prompt evaluation is not well known by the public nor nonophthalmic medical providers, causing a delay that prevents retinopexy and results in surgical repair.²

Most cases of pseudophakic retinal detachment present when the macula is already detached and central vision is affected.⁴ Retinal detachment can pose a significant threat to vision if there is macular involvement.¹

Patients may report visual field defects, floaters, flashes of light, or decreased vision depending on the location and extent of detachment. When macular detachment has occurred, patients experience central visual impairment.

Exam Findings

For patients with symptoms of posterior vitreous detachment, indirect ophthalmoscopy under pupil dilatation is necessary to diagnose retinal tears or retinal detachment.³

When evaluating patients with pseudophakic retinal detachment, the fundal view is often impaired by several factors:⁴

• Anterior or posterior capsular opacification
• Reflections related to the intraocular lens
• Poor mydriasis

The examination may reveal elevation of the neurosensory retina, visible retinal breaks or tears, and subretinal fluid. The extent and configuration of the detachment should be carefully documented, including whether the macula is involved.

Classification

Retinal detachment is classified into three main categories based on pathogenesis:

Rhegmatogenous Retinal Detachment

This is the most common form, caused by fluid passing from the vitreous cavity into the subretinal space through one or more retinal breaks, holes, or tears.^2,1

Tractional Retinal Detachment

This form occurs from traction on the retina without a primary retinal break and represents one of the differential diagnoses for rhegmatogenous detachment.³

Exudative Retinal Detachment

Exudative retinal detachment develops when fluid collects in the subretinal space due to blood-retinal barrier breakdown from inflammatory, infectious, infiltrative, neoplastic, vascular, and degenerative conditions.⁵ This form also represents a differential diagnosis for rhegmatogenous detachment.³

Differential Diagnosis

The differential diagnosis for rhegmatogenous retinal detachment includes:

• Tractional retinal detachment³
• Exudative retinal detachment^3,5
• Retinoschisis³

Exudative retinal detachment may be associated with a spectrum of diseases encountered in uveitis clinics, including inflammatory, infectious, infiltrative, neoplastic, vascular, and degenerative conditions that disrupt the blood-retinal barrier.⁵

Distinguishing between these entities is critical for appropriate management, as rhegmatogenous detachment requires surgical intervention while exudative detachment often requires treatment of the underlying cause.

Management

Rhegmatogenous retinal detachment is an ophthalmologic emergency needing immediate surgical treatment.³

Prevention

RRD prevention is achieved by early accurate diagnosis of retinal tears and prophylactic outpatient retinopexy, which is highly successful in sealing retinal breaks and usually uncomplicated.² Traumatic RRDs can be avoided by protective eye wear in hazardous sports and occupations and timely eye examination and retinopexy.²

Surgical Repair

Surgical techniques used to treat pseudophakic retinal detachment include:⁴

• Scleral buckling
• Pneumatic retinopexy
• Primary pars plana vitrectomy, with or without combined scleral buckling

Anatomical success rates are high after vitreo-retinal surgery for pseudophakic retinal detachment, although a smaller proportion of patients recover good vision following surgery.⁴ Vitrectomy is associated with temporary visual loss and postoperative positioning with limited activity for 1 or 2 weeks.² Phakic patients usually require cataract surgery within 2 years following vitrectomy.²

Prompt diagnosis combined with patient education and appropriate intervention often can avert irrevocable visual impairment.¹

Complications

Some visual loss often results from rhegmatogenous retinal detachment repair, especially if the macula has been detached.² A small fraction of RRDs require multiple surgeries with significant morbidity, including permanent severe visual loss.²

While anatomical success rates are high after vitreo-retinal surgery for pseudophakic retinal detachment, a smaller proportion of patients recover good vision following surgery.⁴

Vitrectomy for RRD repair is associated with temporary visual loss and requires postoperative positioning with limited activity for 1 or 2 weeks.² Phakic patients undergoing vitrectomy usually require cataract surgery within 2 years.²

Pseudophakic retinal detachment is a rare but potentially serious complication of cataract surgery.⁴

Clinical Pearls

• Indirect ophthalmoscopy under pupil dilatation is necessary for patients with symptoms of posterior vitreous detachment to diagnose retinal tears or detachment.³
• The interval between retinal tears and retinal detachment is often long enough for prophylactic laser retinopexy.²
• Prophylactic retinopexy for retinal tears is highly successful in sealing retinal breaks and usually uncomplicated.²
• Most cases of pseudophakic retinal detachment present when the macula is already detached.⁴
• Identification of risk factors and predisposing lesions are important aspects of patient management.¹
• New educational programs are needed to improve public and nonophthalmic provider awareness of retinal tear symptoms and the importance of prompt evaluation.²

Common Pitfalls

• Failing to perform indirect ophthalmoscopy under pupil dilatation in patients with posterior vitreous detachment symptoms, missing retinal tears or early detachment.³
• Delay in evaluation due to lack of patient and provider awareness of retinal tear symptoms, preventing prophylactic retinopexy and necessitating surgical repair.²
• Incomplete fundus examination in pseudophakic patients due to capsular opacification, intraocular lens reflections, or poor mydriasis.⁴
• Mistaking exudative or tractional retinal detachment for rhegmatogenous detachment, leading to inappropriate surgical intervention.³
• Failing to counsel phakic patients undergoing vitrectomy that cataract surgery will likely be needed within 2 years.²