Retinal Detachment


Practice Essentials

Retinal detachment (see the image below) refers to separation of the inner layers of the retina from the underlying retinal pigment epithelium (RPE, choroid). Next to central retinal artery occlusion, chemical burns to the eye, and endophthalmitis, it is one of the most time-critical eye emergencies encountered in the emergency setting.

Retinal detachment. Courtesy of Kresge Eye InstituRetinal detachment. Courtesy of Kresge Eye Institute, Detroit, Michigan.

Signs and symptoms

Symptoms of retinal detachment may include the following:

  • Photopsia (common initially)

  • Visual field defect (developing over time; may help localize detachment)

  • Floaters

The history should include inquiries into the following:

  • History of trauma

  • Previous ophthalmologic surgery

  • Previous eye conditions (eg, uveitis and vitreous hemorrhage)

  • Duration of visual symptoms and visual loss

Physical examination should include the following:

  • Checking of visual acuity

  • External examination for signs of trauma and checking of the visual field

  • Assessment of pupil reaction

  • Measurement of intraocular pressure in both eyes

  • Slit-lamp biomicroscopy

  • Examination of the vitreous for signs of pigment or tobacco dust

  • Examination of the dilated fundus with ophthalmoscopy (preferably indirect)

See Presentation for more detail.

Diagnosis

Retinal detachment occurs by 3 basic mechanisms and thus is classified into the following 3 main types:

  • Rhegmatogenous retinal detachment (the most common type) – This results when a hole, tear, or break in the neuronal layer allows fluid from the vitreous to seep between and separate sensory and RPE layers

  • Traction retinal detachment – This results from adhesions between the vitreous gel/fibrovascular proliferation and the retina

  • Exudative (serous) retinal detachment – This results from exudation of material into the subretinal space from retinal vessels (as in hypertension, central retinal venous occlusion, vasculitis, or papilledema)

Laboratory tests are not helpful in detecting retinal detachment, but basic blood work may be useful if the patient requires surgical intervention.

Unless globe rupture, orbital/facial bone fractures, or intraocular foreign bodies are suspected, diagnostic imaging is not warranted.

See Overview and Workup for more detail.

Management

General treatment measures include the following:

  • Nil per os (NPO) status in anticipation of retinal surgery

  • In trauma cases, protection of the globe with a metallic eye shield

  • Avoidance of any pressure on the globe

  • Limitation of activity to a minimum until further evaluation

  • Treatment of any unstable vital signs in preparation for possible emergency surgery

  • Consideration of referral to a retina specialist (eg, whenever a macula-on retinal detachment is suspected)

Specific techniques for treating retinal detachments include the following:

  • Scleral buckling

  • Pars plana vitrectomy

  • Pneumatic retinopexy

Retinal detachment repair is usually done on an outpatient basis.

See Treatment and Medication for more detail.

Background

Next to central retinal artery occlusion, chemical burns to the eye, and endophthalmitis, a retinal detachment is one of the most time-critical eye emergencies encountered in the ED. Retinal detachment (RD) was first recognized in the early 1700s by de Saint-Yves, but clinical diagnosis remained elusive until Helmholtz invented the ophthalmoscope in 1851.

Tragically, retinal detachments were uniformly blinding until the 1920s when Jules Gonin, MD, pioneered the first repair of retinal detachments in Lausanne, Switzerland. Today, with the advent of scleral buckling and small-gauge pars plana vitrectomy, in addition to laser and cryotherapy techniques, rapid ED diagnosis and treatment of a retinal detachment truly can be a vision-saving opportunity.

Pathophysiology

Eye anatomy is shown in the image below.

Anatomy of the eye. Anatomy of the eye.

Retinal detachment refers to separation of the inner layers of the retina from the underlying retinal pigment epithelium (RPE, choroid). The choroid is a vascular membrane containing large branched pigment cells sandwiched between the retina and sclera. Separation of the sensory retina from the underlying RPE occurs by the following 3 basic mechanisms:

  • A hole, tear, or break in the neuronal layer allowing fluid from the vitreous cavity to seep in between and separate sensory and RPE layers (ie, rhegmatogenous retinal detachment)

  • Traction from inflammatory or vascular fibrous membranes on the surface of the retina, which tether to the vitreous

  • Exudation of material into the subretinal space from retinal vessels such as in hypertension, central retinal venous occlusion, vasculitis, or papilledema

Retinal detachments may be associated with congenital malformations, metabolic disorders, trauma (including previous ocular surgery), [1vascular disease, choroidal tumors, high myopia or vitreous disease, or degeneration.

Of the 3 types of retinal detachment, rhegmatogenous RD is the most common, deriving its name from rhegma, meaning rent or break. Vitreous fluid enters the break and separates the sensory retina from the underlying RPE, resulting in detachment. [2]

Exudative or serous detachments occur when subretinal fluid accumulates and causes detachment without any corresponding break in the retina. The etiologic factors are often tumor growth or inflammation. These types of retinal detachment do not usually require surgical intervention. Correction of the underlying disorder typically leads to resolution of these detachments.

Tractional retinal detachment occurs as a result of adhesions between the vitreous gel/fibrovascular proliferation and the retina. Mechanical forces cause the separation of the retina from the RPE without a retinal break. Advanced adhesion may result in the eventual development of a tear or break. The most common causes of tractional retinal detachment are proliferative diabetic retinopathy, sickle cell disease, advanced retinopathy of prematurity, and penetrating trauma.

Retinal detachments are shown in the images below.

Retinal detachment. Courtesy of Kresge Eye InstituRetinal detachment. Courtesy of Kresge Eye Institute, Detroit, Michigan.
Retinal detachment. Courtesy of Kresge Eye InstituRetinal detachment. Courtesy of Kresge Eye Institute, Detroit, Michigan.
Retinal detachment. Courtesy of Kresge Eye InstituRetinal detachment. Courtesy of Kresge Eye Institute, Detroit, Michigan.
Retinal detachment. Courtesy of Kresge Eye InstituRetinal detachment. Courtesy of Kresge Eye Institute, Detroit, Michigan.
Retinal detachment. Courtesy of Kresge Eye InstituRetinal detachment. Courtesy of Kresge Eye Institute, Detroit, Michigan.
Retinal detachment. Courtesy of Kresge Eye InstituRetinal detachment. Courtesy of Kresge Eye Institute, Detroit, Michigan.

Epidemiology

Frequency

United States

Although 6% of the general population are thought to have retinal breaks, most of these are asymptomatic benign atrophic holes, which are without accompanying pathology and do not lead to retinal detachment. The annual incidence is approximately one in 10,000 or about 1 in 300 over a lifetime. [2Other sources suggest that the age-adjusted incidence of idiopathic retinal detachments is approximately 12.5 cases per 100,000 per year, or about 28,000 cases per year in the US. [3]

Certain groups have higher prevalence than others. Patients with high myopia (>6 diopters) and individuals with aphakia (ie, cataract removal without lens implant) have a higher risk. Cataract extraction complicated by vitreous loss during surgery can have an increased detachment rate of up to 10%.

International

The most common worldwide etiologic factors associated with retinal detachment are myopia (ie, nearsightedness), aphakia, pseudophakia (ie, cataract removal with lens implant), and trauma. Approximately 40-50% of all patients with detachments have myopia, 30-40% have undergone cataract removal, and 10-20% have encountered direct ocular trauma. Traumatic detachments are more common in young persons, and myopic detachment occurs most commonly in persons aged 25-45 years. Although no studies are available to estimate incidence of retinal detachment related to contact sports, specific sports (eg, boxing) have an increased risk of retinal detachment.

Mortality/Morbidity

Estimates reveal that 15% of people with retinal detachments in one eye develop detachment in the other eye. Risk of bilateral detachment is increased (25-30%) in patients who have had bilateral cataract extraction.

Race

There exists no racial predilection for retinal detachment incidence.

Sex

There exists no gender predilection for retinal detachment incidence.

Age

As the population ages, retinal detachments (RDs) are becoming more common. Retinal detachment usually occurs in persons aged 40-70 years. However, paintball injuries in young children and teens are becoming increasingly common causes of eye injuries, including traumatic retinal detachments.

Prognosis

As the retina is neuro-sensitive tissue, visual prognosis can be difficult to predict. Generally, a retinal detachment without macular involvement tends to have a better final visual prognosis.



History

Initial symptoms of retinal detachment commonly include the sensation of a flashing light (photopsia) related to retinal traction and often accompanied by a shower of floaters and vision loss.

Over time, the patient may report a shadow in the peripheral visual field, which, if ignored, may spread to involve the entire visual field in a matter of days. Vision loss may be described as cloudy, irregular, or curtainlike.

Retinal tissue is stimulated by light but also responds to mechanical disturbances. Flashing lights usually are caused by separation of the posterior vitreous. As the vitreous gel separates from the retina, it stimulates the retinal tissue mechanically, resulting in the release of phosphenes and the sensation of light.

Pathologic stimulation of the retina and production of phosphenes cause photopsia.

If a retinal detachment involves the macula, acuity may be severely reduced.

The location of the light sensation in the patient's visual field has no correlation to the location of a retinal tear.

Floaters are a very common visual symptom in the population; thus, distinguishing their etiology requires eliciting a detailed history. The sudden onset of large floaters in the center of the visual axis may indicate posterior vitreous detachment (PVD). The patient observes a circular floater when the vitreous detaches from its annular ring surrounding the optic nerve (referred to as Weiss ring). More ominous and concerning is the description of hundreds of tiny black specks appearing before the eye, as this maybe be indicative of a vitreous hemorrhage, resulting from disruption of a retinal vessel caused by a retinal tear or mechanical traction of a vitreoretinal adhesion. A few hours after the initial shower of black spots, the patient can note cobwebs that result from blood forming irregular clots. Generally, the new onset of floaters associated with flashing lights is highly suggestive of a retinal tear.

While symptoms of photopsia and floaters are not helpful in locating the position of the retinal tear or detachment, the visual field defect can be helpful in locating the detachment.

Bullous (ie, large ballooning) detachments produce dense visual field defects (ie, blackness), and flat detachments produce relative field defects (ie, grayness).

Inquire about history of trauma, including whether it occurred several months before the symptoms or coincided with the onset of symptoms. Documentation of head or ocular trauma may be subject to legal investigation, especially in children.

Note previous surgery, including cataract extraction, intraocular foreign body removal, and retinal procedures.

Question the patient about previous conditions, such as uveitis, vitreous hemorrhage, amblyopia, glaucoma, and diabetic retinopathy. Query about family history of eye disease because, although RDs usually are sporadic events, certain pedigrees may be prone to detachment.

Determine length of time there has been visual symptoms and visual loss. This can help determine the appropriate timing of treatment

Physical

Check visual acuity at near and distance, correcting for refractive error.

Conduct an external examination for signs of trauma, checking the visual field (usually a confrontation field examination is adequate). Visual fields can help isolate the location of the retinal detachment.

Check pupil reaction (a fixed dilated pupil may indicate previous trauma; a positive Marcus-Gunn pupil can occur with any disturbance of the afferent pupillomotor pathway, including retinal detachment).

Check intraocular pressure measurement in both eyes (relative hypotony of >4-5 mm Hg less than the fellow eye is common).

Administer slit-lamp biomicroscopy

Examine the vitreous for signs of pigment or tobacco dust (ie, Shafer sign), which is suggestive for a retinal tear in 70% of cases with no previous eye disease or surgery.

Conduct a dilated fundus examination with ophthalmoscopy (panoptic ophthalmoscope may be used). Indirect ophthalmoscopy is the definitive means of diagnosing retinal detachment. Direct funduscopy may detect vitreous hemorrhage and large detachment of the posterior pole, but it is inadequate for complete examination because of the lower magnification and illumination, lack of stereopsis, and limited view of the peripheral retina. Obvious detachment is observed as marked elevation of the retina, which appears gray with dark blood vessels that may lie in folds. The detached retina may undulate and appear out of focus.Shallow detachments are much more difficult to detect; thus, comparing the suspected area with an adjacent normal quadrant is helpful to detect any change in retinal transparency. A pigmented or nonpigmented line may demarcate the limit of a detachment.

Complications

Loss of vision to hand motion or light perception is a frequent complication of retinal detachments that involve the macula.



History

Initial symptoms of retinal detachment commonly include the sensation of a flashing light (photopsia) related to retinal traction and often accompanied by a shower of floaters and vision loss.

Over time, the patient may report a shadow in the peripheral visual field, which, if ignored, may spread to involve the entire visual field in a matter of days. Vision loss may be described as cloudy, irregular, or curtainlike.

Retinal tissue is stimulated by light but also responds to mechanical disturbances. Flashing lights usually are caused by separation of the posterior vitreous. As the vitreous gel separates from the retina, it stimulates the retinal tissue mechanically, resulting in the release of phosphenes and the sensation of light.

Pathologic stimulation of the retina and production of phosphenes cause photopsia.

If a retinal detachment involves the macula, acuity may be severely reduced.

The location of the light sensation in the patient's visual field has no correlation to the location of a retinal tear.

Floaters are a very common visual symptom in the population; thus, distinguishing their etiology requires eliciting a detailed history. The sudden onset of large floaters in the center of the visual axis may indicate posterior vitreous detachment (PVD). The patient observes a circular floater when the vitreous detaches from its annular ring surrounding the optic nerve (referred to as Weiss ring). More ominous and concerning is the description of hundreds of tiny black specks appearing before the eye, as this maybe be indicative of a vitreous hemorrhage, resulting from disruption of a retinal vessel caused by a retinal tear or mechanical traction of a vitreoretinal adhesion. A few hours after the initial shower of black spots, the patient can note cobwebs that result from blood forming irregular clots. Generally, the new onset of floaters associated with flashing lights is highly suggestive of a retinal tear.

While symptoms of photopsia and floaters are not helpful in locating the position of the retinal tear or detachment, the visual field defect can be helpful in locating the detachment.

Bullous (ie, large ballooning) detachments produce dense visual field defects (ie, blackness), and flat detachments produce relative field defects (ie, grayness).

Inquire about history of trauma, including whether it occurred several months before the symptoms or coincided with the onset of symptoms. Documentation of head or ocular trauma may be subject to legal investigation, especially in children.

Note previous surgery, including cataract extraction, intraocular foreign body removal, and retinal procedures.

Question the patient about previous conditions, such as uveitis, vitreous hemorrhage, amblyopia, glaucoma, and diabetic retinopathy. Query about family history of eye disease because, although RDs usually are sporadic events, certain pedigrees may be prone to detachment.

Determine length of time there has been visual symptoms and visual loss. This can help determine the appropriate timing of treatment

Physical

Check visual acuity at near and distance, correcting for refractive error.

Conduct an external examination for signs of trauma, checking the visual field (usually a confrontation field examination is adequate). Visual fields can help isolate the location of the retinal detachment.

Check pupil reaction (a fixed dilated pupil may indicate previous trauma; a positive Marcus-Gunn pupil can occur with any disturbance of the afferent pupillomotor pathway, including retinal detachment).

Check intraocular pressure measurement in both eyes (relative hypotony of >4-5 mm Hg less than the fellow eye is common).

Administer slit-lamp biomicroscopy

Examine the vitreous for signs of pigment or tobacco dust (ie, Shafer sign), which is suggestive for a retinal tear in 70% of cases with no previous eye disease or surgery.

Conduct a dilated fundus examination with ophthalmoscopy (panoptic ophthalmoscope may be used). Indirect ophthalmoscopy is the definitive means of diagnosing retinal detachment. Direct funduscopy may detect vitreous hemorrhage and large detachment of the posterior pole, but it is inadequate for complete examination because of the lower magnification and illumination, lack of stereopsis, and limited view of the peripheral retina. Obvious detachment is observed as marked elevation of the retina, which appears gray with dark blood vessels that may lie in folds. The detached retina may undulate and appear out of focus.Shallow detachments are much more difficult to detect; thus, comparing the suspected area with an adjacent normal quadrant is helpful to detect any change in retinal transparency. A pigmented or nonpigmented line may demarcate the limit of a detachment.

Complications

Loss of vision to hand motion or light perception is a frequent complication of retinal detachments that involve the macula.

Differential Diagnoses


Laboratory Studies

Laboratory tests are not helpful in detecting retinal detachment and are not warranted in the acute care of the patient. However, if the patient requires surgical intervention, it may be useful to have basic blood work (BMP, PT/PTT, INR, HbA1C). This is especially important in diabetics and those on systemic anti-coagulation.

Imaging Studies

Unless globe rupture, orbital/facial bone fractures or intraocular foreign bodies are suspected, imaging techniques, such as CT scans or MRIs, are not warranted to evaluate for retinal detachments.In difficult cases, bedside ocular ultrasonography can facilitate prompt diagnosis of retinal detachment. Potential ultrasonographic mimics of retinal detachment (eg, posterior vitreous detachment [PVD] and vitreous hemorrhage [VH]) should be excluded.

Sonogram of retinal detachment. Courtesy of Bruce Sonogram of retinal detachment. Courtesy of Bruce Lo, MD.

Prehospital Care

When patients with retinal detachment or their family member contacts their physician, they should be advised to do the following:

  • Keep the patient NPO (absolutely no solid foods or fluids) in anticipation of retinal surgery

  • In cases of associated trauma, protect the globe with metallic eye shield

  • Avoid any pressure on the globe and to limit activity to a minimum until further evaluation

Emergency Department Care

ED treatment of retinal detachment consists of evaluating the patient and treating any unstable vital signs, preparing the patient for possible emergency surgery. Please see the examination guidelines as stated above.

In difficult cases, bedside ocular ultrasonography can facilitate prompt diagnosis of retinal detachment. Potential ultrasonographic mimics of retinal detachment (eg, posterior vitreous detachment [PVD] and vitreous hemorrhage [VH]) should be excluded.

Patient follow up should be based upon macula status: Whenever a macula-on retinal detachment is suspected, a retina specialist should evaluate the patient within 24 hours.

All patients should be instructed to limit strenuous physical activity. Upon discharge from the ED, patients should be provided with the name and contact information for a retina specialist located close to their home.

There exists a multitude of techniques for treating retinal detachments, including scleral buckling, pars plana vitrectomy, and pneumatic retinopexy. The retinal detachment repair is usually done on an outpatient basis.

Consultations

Ideally, patients with retinal detachment should be quickly referred to a retina specialist. The timing of surgical intervention is typically based on the status of the macula.

Further Inpatient Care

Immediate ophthalmologic referral is mandatory for patients with retinal detachment.

Transfer

Emergent transfer to a facility with an available retina specialist is rarely indicated, as majority of cases can be evaluated within 24 hours. In some cases, transfer to a facility with an available ophthalmologist or retinal specialist is in the patient's best interest after initial ophthalmologic evaluation. Make these decisions in accordance with the patient's wishes and the direction of the ophthalmology consultant.


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