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Home , Macular degeneration, Photopsia, Red reflex, Retinal detachment, Scotoma

Evaluation and Management of Sus- pected RAY F. GARIANO, M.D., PH.D., Stanford University School of Medicine, Stanford, California CHANG-HEE KIM, M.D., Naval Medical Center, San Diego, California

Retinal detachment often is a preventable cause of vision loss. There are three types of retinal detachments: exudative, tractional, and rhegmatogenous. The most common type is rhegmatogenous, which results from retinal breaks caused by vitreoretinal traction. Risk factors for retinal detachment include advancing age, previous , , and trauma. Patients typically will present with symptoms such as light flashes, , peripheral loss, and . Early interven- tion facilitates prevention of retinal detachment after formation of retinal breaks and improves visual outcomes of retinal detachment surgery. Patients with acute onset of flashes or floaters should be referred to an ophthalmologist. (Am Fam Physician 2004;69:1691-8. Copyright© 2004 American Academy of Family Physicians.)

See page 1591 for defi- etinal detachment is relatively separates from the underlying retinal pigment nitions of strength-of- uncommon, affecting only epithelium (Figure 1, lower right). Retinal recommendation labels. one in 10,000 people per year, detachments are classified into three patho- or approximately one in 300 genetic types (Table 1). A patient may present patients in the course of a with one or more of these types. Rlifetime.1 Retinal detachment often is repaired Exudative (or serous) retinal detachment with little or no vision loss; therefore, it is results from the accumulation of serous and/ a much less significant cause of irreversible or hemorrhagic fluid in the subretinal space blindness than other retinal diseases, such as because of hydrostatic factors (e.g., severe acute diabetic and macular degenera- ), or (e.g., sarcoid tion.2 Retinal detachment should be consid- ), or neoplastic effusions. Exudative reti- ered in the differential diagnosis of vision nal detachment generally resolves with success- loss, however, because it is more prevalent ful treatment of the underlying disease, and in defined subpopulations and may require visual recovery is often excellent. urgent surgical repair. The second type of detachment, tractional retinal detachment, occurs via centripetal Pathogenesis of Retinal Detachment mechanical forces on the , usually medi- The retina is a neurosensory tissue that lines ated by fibrotic tissue resulting from previ- the interior posterior two thirds of the ous hemorrhage, injury, surgery, infection, or (Figure 1, left). The central retina, or macula, inflammation. Correction of tractional retinal and the centermost macula, or fovea, exhibit detachment requires disengaging scar tissue structural and cellular specializations for fine from the retinal surface. In patients with trac- central acuity. tional retinal detachment, vision outcomes Retinal detachment results when physi- are often poor. ologic and anatomic mechanisms of reti- The third and most common type is rheg- nal attachment are overcome and the retina matogenous retinal detachment. The key pathogenetic steps of rhegmatogenous retinal detachment are illustrated in Figure 2. The vit- reous humor is a hydrated gel whose structure Retinal detachment often is repaired with little or no is maintained by a collagenous and mucopoly- vision loss. saccharide matrix (Figure 2a). As persons age, this macromolecular network begins to liquefy

Downloaded from the American Family Physician Web site at www.aafp.org/afp. Copyright© 2004 American Academy of Family Physicians. For the private, noncommercial use of one individual user of the Web site. All other rights reserved. Contact [email protected] for copyright questions and/or permission requests. and collapse, the vitreous shrinks, and vitreoret- inal traction develops.3 Eventually, the vitreous partly separates from the retinal surface, which is known as posterior vitreous detachment (Figure 2b). Approximately one in four per- sons develops a posterior vitreous detachment Zonules between 61 and 70 years of age, and nearly two Vitreous thirds have posterior vitreous detachment after 70 years of age.4 Posterior vitreous detachment is harmless by itself, though bothersome float- Vitreous ers (blood or retinal pigment epithelium cells) may develop and persist. However, in 10 to 15 Vessel percent of patients with symptomatic posterior Retina vitreous detachment, a retinal flap tear or hole Photoreceptor forms as the vitreous pulls away from the retina, Retina Plane of cells especially in the periphery where the retina is separation 5 Optic Retinal pigment thinner (Figure 2c). epithelium Retinal tears may occur without symptoms, Choroid but often (luminous rays or light Sclera Vessel flashes in vision) is noted. Photopsia results

from mechanical stimulation of the retina ILLUSTRATION BY MARCIA ILLUSTRATION HARTSOCK FIGURE 1. (Left) Schematic diagram indicating several ocular structures. by vitreoretinal traction. When the retina (Lower right) Cross-section through the posterior eye wall shows the tears, blood and retinal pigment epithelium retina in contact with the vitreous at its inner aspect. Photoreceptor cells may enter the vitreous cavity and are cells in the outermost retina adhere to the retinal pigment epithelium, perceived as floaters (Figure 2c). Patients with which appears as a darkly pigmented cellular monolayer above the symptomatic retinal tears are at high risk of vascular choroid. The sclera is the white outer coat of the eye that invests the and is continuous with the dura. The plane of progression to retinal detachment. separation in retinal detachment is between the retina and the retinal Rhegmatogenous detachment occurs when pigment epithelium. Vision is lost because photoreceptor cells require liquid vitreous enters the subretinal space contact with the retinal pigment epithelium and choroid for metabolic through a retinal break and creates a plane of and vascular support. dissection between the retina and retinal pig- ment epithelium (Figure 2d). Over time, the TABLE 1 area of detachment increases as more fluid Classification and Management of Retinal Detachment passes through the retinal break. Symptoms depend on the location and extent of the Type Etiology Management detachment. For example, a small detachment in the inferior retina results in a small supe- Exudative (serous) Inflammation (sarcoid uveitis), Treat underlying disease. rior visual field defect, while a large temporal severe acute hypertension, detachment causes extensive nasal field loss. neoplastic tumors Tractional Fibrosis* Surgical excision of fibrosis When the macula detaches, central acuity is Rhegmatogenous Retinal tears† Surgery lost. If untreated, nearly all rhegmatogenous retinal detachments progress to involve the *—Caused by previous retinal detachment, surgery, trauma, or proliferative macula. retinopathy. †—See Figure 2. Epidemiology of Retinal Detachment The role of the vitreous in the pathogenesis of retinal breaks and detachments clarifies the

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TABLE 2 Risk Factors for Retinal Detachment Approximately one in four persons develops a posterior vitreous detachment between 61 and 70 years of age, and Common Less Common nearly two thirds have posterior vitreous detachment after Aging Congenital eye diseases 70 years of age. Focal retinal Family history of detachment atrophy* Hereditary vitreoretinopathy Myopia (axial) Prematurity Trauma Uveitis Vitreous gel *—Atrophic retinal lesions are designated by descrip- tive terms such as “lattice” degeneration. A Retina

risk factors for retinal detachment (Table 2). Detachment is more likely with advancing age because molecular breakdown and shrinkage B Fluid-filled space of the vitreous humor increases over time.4,6 Previous cataract surgery commonly is associ- Retina ated with retinal detachment.7 The detach- ment occurs because following the surgical removal of the lens during cataract surgery, Retinal break vitreous may pass into the C anterior chamber and escape through the trabecular meshwork. Shrinkage and detach- Fluid-filled space ment of the vitreous are accelerated, and increase the risk of development to retinal tears. Retinal detachment occurs in approxi- mately 1 percent of patients in the weeks to D years following cataract surgery.8 Myopia, or nearsightedness, is another lead- 9 ing risk factor for retinal detachment. In most Retinal detachment patients with moderate or severe myopia, the axial (anteroposterior) length of the eye is greater, resulting in an egg-shaped . As a consequence, centripetal vitreoretinal traction FIGURE 2. Pathogenesis of rhegmatogenous retinal detachment. (A) increases and posterior vitreous detachment The vitreous gel evenly fills the vitreous cavity and is adherent to the retinal surface. (B) With aging and other factors, the gel shrinks, may occur at a younger age than in persons exerts a centripetal traction force on the retina (arrows), and eventu- 4 without myopia. Also, in myopic , the ally separates from the retina, a condition known as posterior vitreous retina is thinner and more prone to tear or detachment; a fluid-filled space enlarges between the retracting gel hole formation at the time of posterior vitreous and the retinal surface. (C) In susceptible persons, vitreoretinal traction detachment. Therefore, persons with myopia and posterior vitreous detachment result in a retinal break, from which blood and retinal pigment epithelium cells may enter the vitreous cav- are at risk of retinal detachment even in early ity (floaters). (D) As liquid vitreous passes through the break (curved adulthood; acute symptoms of flashes and/or arrow), it dissects the retina from the underlying retinal pigment epi- floaters in these patients warrant a thorough thelium, resulting in retinal detachment.

APRIL 1, 2004 / VOLUME 69, NUMBER 7 www.aafp.org/afp AMERICAN FAMILY PHYSICIAN-1693 globe may generate sufficient vitreoretinal Patients with symptomatic retinal tears are at high risk of traction to produce retinal tears.11 Alterna- progression to retinal detachment. tively, retinal detachment may occur weeks, months, or even years after trauma because vitreous contraction is accelerated by inflam- matory and blood-borne mediators that access examination. Focal areas of periph- the vitreous cavity at the time of injury.12 eral retinal thinning and vitreoretinal adhesion Despite these concerns, retinal detachment occur less often in those without myopia, and rarely follows head and periocular trauma,13,14 are associated with retinal detachment.10 and fundus examination is warranted only if Trauma precipitates retinal detachment for visual symptoms or external or radiographic several reasons. At the moment of impact, evidence of ocular injury are present. rapid compression and decompression of the Less common associations with rhegmato- genous retinal detachment include a family TABLE 3 history of detachment, a history of congenital Differential Diagnoses of Retinal Detachment eye diseases (such as or cataract), hereditary vitreopathies with abnormal vitre- Symptom Cause of symptom Differential diagnosis ous gel and high myopia (such as Stickler’s syndrome), and previous retinopathy of pre- Photopsia Vitreoretinal traction PVD, , , maturity (Table 2). hypotension, transient ischemic attack Floaters Vitreous cells, blood PVD, PDR, uveitis Evaluation of Patients with Suspected Visual field loss Peripheral detachment , CVA, BRVO, BRAO Retinal Detachment Blurred vision Macular detachment A careful history helps to distinguish reti- nal detachment from other conditions with PVD = posterior vitreous detachment; PDR = proliferative diabetic retinopathy; CVA = cerebrovascular accident; BRVO = branch retinal vein occlusion; BRAO = similar symptoms (Table 3). Floaters caused branch retinal artery occlusion. by acute posterior vitreous detachment, espe- cially in the presence of a retinal tear, occur more abruptly and dramatically than do the floaters that people experience for much The Authors of their lifetime. Floaters are described by patients as fine dots, veils, cobwebs, clouds, RAY F. GARIANO, M.D., PH.D., is an associate clinical professor in the department of or strings. Similar floaters occur with other at Stanford University School of Medicine, Stanford, Calif., and chief of the retina division at the Santa Clara Valley Medical Center, Santa Clara, Calif. He causes of intraocular , such as pro- received his medical degree from the University of California, San Diego, where he also liferative diabetic retinopathy, trauma, and completed a residency in ophthalmology. Dr. Gariano completed a retina fellowship ocular inflammation (uveitis). at the University of Washington, Seattle. He is a former director of the Retinal Service at Yale University, New Haven, Conn., and worked as a staff physician in the ophthal- Light flashes may precede migraine head- mology department at the Scripps Clinic, San Diego, and as a visiting scientist in the aches, but these typically occur bilaterally department of cell biology at The Scripps Research Institute, La Jolla, Calif. (though often in one area of the visual field). CHANG-HEE KIM, M.D., is a naval flight surgeon at Naval Medical Center, North Photopsia that is induced by eye movements Island, San Diego. He received his medical degree from Texas A&M University College may indicate optic neuritis. Light flashes also of Medicine, College Station, Tex. Dr. Kim completed an internship in pediatrics at the National Naval Medical Center, Bethesda, Md. may occur with postural hypotension and vasovagal reactions; these are bilateral and Address correspondence to Ray F. Gariano, M.D., Ph.D., Stanford University School of Medicine, Department of Ophthalmology, 300 Pasteur Dr., A157, Stanford, CA 94305 often accompanied by temporary dimming of (e-mail: [email protected]). Reprints are not available from the vision and lightheadedness. authors. Visual field loss caused by retinal detach- ment begins suddenly, usually in the periph-

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ery, and progresses toward the central visual axis over hours to weeks; patients may describe All patients with acute onset of flashes or floaters should be this as a dim “shadow” or “curtain.” Field referred to an ophthalmologist. loss caused by or other central processes is always bilateral, stable, and homonymous, due to crossing of nasal retinal projections at the . Even in exhibits acute visual field loss, whether sub- patients with severe field loss caused by cere- jective or demonstrable by confrontation, bral disease, the macula is spared and central immediate referral is recommended. When vision persists. Visual loss from a transient the macula detaches, the potential to main- ischemic attack may be unilateral, but is epi- tain normal vision is often lost. Thus, patients sodic, not persistent or progressive as in cases with extramacular detachment require more of retinal detachment, and may be accom- urgent management, even though they may panied by other neurologic symptoms. Fixed present with excellent central . field defects of variable size occur in patients These patients may benefit from direct refer- with retinal vascular occlusion; these patients ral to a retinal specialist to avoid the delay often have hypertension or other atherogenic associated with additional examination by a diseases, lack acute flashes, floaters, or other general ophthalmologist or optometrist. In risk factors for retinal detachment, and may North America, most retinal detachment sur- exhibit flame hemorrhage or arteriolar plaques geries are performed by retinal specialists. by . The direct (hand-held) ophthalmoscope is In patients with optic nerve disorders, useful to detect an altered sometimes visual field loss is typically central or para- associated with retinal detachment. However, central, pupillary reactions are diminished in because its view is narrow, a normal examina- the affected eye, and optic nerve head edema tion with the direct ophthalmoscope cannot may be evident. is the exclude a diagnosis of retinal detachment. leading cause of painless sudden vision loss Ophthalmologists use indirect examination in older patients, but the is central techniques that greatly enhance visualization and the peripheral field is intact. Common of the peripheral fundus. In cases where severe ocular , such as , , periorbital edema, or opacity irritation, tearing, intermittent blurring, and (e.g., cataract, intraocular blood) preclude conjunctival redness, are unrelated to retinal ophthalmoscopy, ophthalmic ultrasonogra- detachment. phy is superior to magnetic resonance imag- Prompt referral and evaluation of patients ing and computed tomography for revealing who are suspected of having retinal tears occult retinal detachment (Figure 3). are important because treatment of retinal tears is highly effective in preventing reti- Treatment of Retinal Detachment nal detachment, and because progression of Prevention is important in the treatment retinal detachment into the macula typically of retinal detachment. Protective eyewear is results in permanent visual loss. All patients recommended for persons participating in with acute onset of flashes or floaters should contact sports, especially if they have moder- be referred to an ophthalmologist (Table 4). ate or severe myopia. Patients undergoing If the patient has additional risk factors (e.g., cataract surgery must be instructed about the myopia, previous cataract surgery, trauma, importance of reporting symptoms of retinal retinal detachment in the fellow eye, family tears and detachments. history of detachment), suspicion of reti- The greatest opportunity for prevention nal detachment is heightened. If the patient exists in the hours to weeks following posterior

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V vitreous detachment and retinal tear forma- tion, because there is often a variable interval between retinal break and detachment.15 Only 1 to 2 percent of patients with a posterior vitreous detachment have a retinal break. If is present (often mani- fested as more marked floaters and blurring), this risk increases to 70 percent.16 Symptom- atic retinal breaks are surrounded with laser or cryo burns to create a chorioretinal scar that prevents fluid access into the subretinal space. This treatment is over 95 percent effec- tive in preventing progression of a retinal tear to retinal detachment17 (Figures 4a and 4b). Surgical correction of retinal detachment aims to relieve vitreoretinal traction, and close retinal tears and holes. Scleral buckling tech- niques achieve reattachment in over 90 percent of cases18 (Figure 4c). An alternative means to relieve vitreoretinal traction is to remove the vitreous humor. This approach, called poste- rior , is successful in 75 to 90 percent 19 FIGURE 3. B-mode ocular ultrasound. This ultrasound reliably detects of patients. Less invasive procedures, such as retinal detachment and is particularly useful in children and unco- pneumatic retinopexy, allow repair of selected operative patients, and when the view to the retina is obscured by detachments in a clinic or office setting.20 periorbital edema, blood, cataract, or other opacities. (Top) Partly If the central macula has not yet detached detached retina (white arrowhead) lies within an otherwise echo- when the repair is achieved, visual acuity equal lucent vitreous cavity. (Bottom) Detached retina (white arrowhead) caused by traction on the retinal surface by intravitreal fibrosis (white to preretinal detachment levels can be expected. arrow) in a patient with diabetic retinopathy. (C = cornea; L = lens; V However, if the central macula is detached at = vitreous cavity; S = sclera) the time of repair, final visual recovery may vary

Retinal br eak location

Retinal tear A B C F I G U R E 4 . ( A ) U - s h a p e d r e t i n a l t e a r w i t h v i t r e o u s a d h e r e n t t o i t s a n t e r i o r f l a p ( a b o v e ) . ( B ) P o s t - t r e a t m e n t p h o t o o f a r e t i- n a l t e a r s u r r o u n d e d b y m u l t i p l e l a s e r - i n d u c e d b u r n s t h a t s t r e n g t h e n r e t i n a l a d h e s i o n t o u n d e r l y i n g t i s s u e s . ( C ) I n s c l e r a l b u c k l i n g , a p l i a b l e s i l i c o n e e l e m e n t i s p o s i t i o n e d b e n e a t h t h e r e c t u s m u s c l e s a n d s u t u r e d t o t h e s c l e r a . T h e i n w a r d s c l e r a l i n d e n t a t i o n ( b u c k l i n g ) b r i n g s t h e d e t a c h e d r e t i n a i n c l o s e r a p p o s i t i o n t o t h e e y e w a l l a n d r e d u c e s i n t e r n a l v i t r e o r e t i n a l t r a c t i o n .

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from none to nearly complete, depending on Strength of Recommendations the duration and degree of elevation of macu- lar detachment and the patient’s age. There- Strength of fore, surgical repair is indicated more urgently Key clinical recommendation recommendation References in patients with preserved central acuity, less Therefore, surgical repair is indicated more B 21,22 urgently in patients whose macula detached urgently in patients with preserved central in the previous hours to days, and routinely acuity, less urgently in patients whose macula in those whose macula has been detached for detached in the previous hours to days, and several days or weeks21,22 (Table 4). Within routinely in those whose macula has been months, photoreceptors in a detached retina detached for several days or weeks. suffer severe and irreversible damage caused by the separation from the underlying choroidal vascular supply (Figure 1, lower right), and repair yields less visual improvement. elusive.26 Retinal detachment surgery fails in 5 to The authors indicate that they do not have any 10 percent of patients because of the growth of conflicts of interest. Sources of funding: none reported. scar tissue on the retinal surface in the weeks 23 following repair. Sources of fibrosis include The authors thank Steven A. Green, M.D., for help- blood cells, fibrin, inflammatory cells associ- ful comments regarding the manuscript. ated with postoperative healing, and retinal astrocytes and retinal pigment epithelium REFERENCES cells that enter the vitreous cavity when a 1. Haimann MH, Burton TC, Brown CK. Epidemiology retinal tear forms.24 Fibrotic tissue may exert of retinal detachment. Arch Ophthalmol 1982;100: 289-92. sufficient inward traction to cause redetach- 2. Podgor MJ, Leske MC, Ederer F. Incidence esti- ment. This condition, known as proliferative mates for lens changes, macular changes, open- vitreoretinopathy, is surgically corrected in angle glaucoma and diabetic retinopathy. Am J Epidemiol 1983;118:206-12. 60 to 90 percent of patients, though visual 3. Sebag J. of the vitreous. Eye 1987;1(pt 2): 25 acuity is often poor. of epireti- 254-62. nal fibrosis with antiproliferative agents is 4. Foos RY, Wheeler NC. Vitreoretinal juncture. Syn- chysis senilis and posterior vitreous detachment. being intensively investigated, but remains Ophthalmology 1982;89:1502-12. 5. Hikichi T, Trempe CL. Relationship between floaters, light flashes, or both, and complications of poste- TABLE 4 rior vitreous detachment. Am J Ophthalmol 1994; Guidelines for Referral 117:593-8. to an Ophthalmologist 6. Flood MT, Balazs EA. Hyaluronic acid content in the developing and aging human liquid and gel vitre- ous. Invest Ophthalmol Vis Sci 1977;16(suppl):67. Presentation Referral 7. Javitt JC, Street DA, Tielsch JM, Wang Q, Kolb MM, Schien O, et al. National outcomes of cataract ext- Acute Within one week raction. Retinal detachment and Acute floaters Within one week, sooner after outpatient cataract surgery. Cataract Patient Outcomes Research Team. Ophthalmology 1994; if the floaters worsen 101:100-5. Visual field loss Emergent, within one day, 8. Norregaard JC, Thoning H, Andersen TF, Bernth- if possible Petersen P, Javitt JC, Anderson GF. Risk of retinal Any of above, Routine, within one to two detachment following cataract extraction: results chronic months from the International Cataract Surgery Outcomes Acute blurring Urgent, within one to three Study. Br J Ophthalmol 1996;80:689-93. 9. Schepens CL, Marden D. Data on the natural his- days tory of retinal detachment. Further characteriza- tion of certain unilateral nontraumatic cases. Am J Ophthalmol 1966;61:213-26.

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