Retinal Detachment

Essentials of Diagnosis

• Loss of vision in one eye that is usually rapid, possibly with "curtain" spreading across field of vision

• No pain or redness

• Detachment seen by ophthalmoscopy

General Considerations

• Most cases are due to development of one or more peripheral retinal tears or holes (rhegmatogenous retinal detachment); this usually results from posterior vitreous detachment, related to degenerative changes in the vitreous

• Generally occurs in persons over 50 years of age

• Nearsightedness and cataract extraction are the two most common predisposing causes

• May also be caused by penetrating or blunt ocular trauma

• Once there is a defect in the retina, fluid vitreous is able to pass under the sensory retina and, with the added effects of vitreous traction and gravity, progressive retinal detachment results

• Tractional retinal detachment occurs when there is preretinal fibrosis, such as in proliferative retinopathy due to diabetic retinopathy or retinal vein occlusion or as a complication of rhegmatogenous retinal detachment

• Exudative retinal detachment results from accumulation of subretinal fluid, such as in wet ("neovascular") age-related macular degeneration or secondary to choroidal tumor

• Rhegmatogenous retinal detachment usually starts in the superior temporal area, spreading rapidly to cause visual field loss that starts inferiorly and expands upward but can occur at other locations

• Premonitory symptoms of the predisposing vitreous degeneration and vitreo-retinal traction include

  • Recent onset of or increase in floaters (moving spots or strands like cobwebs in the visual field)

  • Photopsias (flashes of light)

• Central vision remains intact until the central macula becomes detached

• Retina may be elevated in the vitreous cavity with an irregular surface

• One or more retinal tears or holes are usually found on retinal examination with scleral depression, which is a technique to examine the peripheral retina using a cotton tip swab or blunt instrument to push on, or depress, the external eye to evaluate the peripheral retina through a dilated pupil

• A macular hole, usually caused by traction from the vitreous or scar tissue on the retinal surface (epiretinal membrane), causes reduction of central vision

• In idiopathic cases, the hole occurs from localized retinal traction with retinal separation at the fovea, whereas in macular hole due to trauma or nearsightedness, there is a risk of progression to total retinal detachment

• In tractional retinal detachment, there is irregular retinal elevation adherent to scar tissue on the retinal surface, sometimes extending into the vitreous

• In exudative retinal detachment, the retina is dome-shaped and the subretinal fluid shifts position with changes in posture

• Ocular ultrasonography assists the detection and characterization of retinal detachment

• Laser photocoagulation to the retina or cryotherapy to the sclera

  • Treats rhegmatogenous retinal detachments

  • Closes all of the retinal tears and holes by forming a permanent adhesion between the neurosensory retina, the retinal pigment epithelium, and the choroid

• Pneumatic retinopexy

  • Used for certain types of uncomplicated retinal detachment, in which an expansile gas is injected into the vitreous cavity followed by positioning of the patient's head to facilitate apposition between the gas and the hole to permit reattachment of the retina

  • Once the retina is reattached, the defects are surrounded by laser photocoagulation or cryotherapy scars; these two methods are also used to seal retinal defects without associated detachment

• In complicated retinal detachments, particularly traction retinal detachments, retinal reattachment can be accomplished only by

  • Pars plana vitrectomy

  • Direct manipulation of the retina

  • Internal tamponade of the retina with air, expansile gas, or silicone oil

    • Presence of an expansile gas within the eye is a contraindication to air travel, mountaineering at high altitude, and nitrous oxide anesthesia

    • Such gases persist in the globe for weeks after surgery

• Treatment of exudative retinal detachments is determined by the underlying cause

Prognosis

• About 90% of uncomplicated rhegmatogenous retinal detachments can be cured with one operation

• The visual prognosis is worse if the macula is detached or if the detachment is of long duration

When to Refer

• All cases of retinal detachment must be referred urgently to an ophthalmologist, and emergently if central vision is good because this indicates that the macula has not detached