Retinal Detachment

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Retinal Detachment
Classification and external resources
DiseasesDB 11417


Visit EyeSmart from the American Academy of Ophthalmology for a brief, patient-friendly summary of retinal detachments.

Disease Entity

Disease

Retinal detachment is a sight threatening condition with an incidence of approximately 1 in 10000.[1] [2] Before the 1920’s, this was a permanently blinding condition. In subsequent years, Jules Gonin, MD, pioneered the first repair of retinal detachments in Lausanne, Switzerland.[3] In 1945 after the development of the binocular indirect ophthalmoscope by Charles Schepens, MD, techniques for retinal detachment repair improved. In the last 50 years techniques in scleral buckling, pneumatic retinopexy and vitrectomy have made the repair of retinal detachments more manageable with better visual outcomes.

Risk Factors for Rhegmatogenous Retinal Detachment

  1. Lattice degeneration
  2. Peripheral retinal breaks
  3. Pathologic myopia
  4. Previous intraocular surgery
  5. Trauma
  6. Previous retinal detachment
  7. Family history


Lattice degeneration is considered the most important peripheral retinal degeneration process that predisposes to a rhegmatogenous retinal detachment.[4] Other peripheral lesions having slight increased risk of retinal detachment include Ora bays, meridional folds and complexes, and cystic retinal tufts.

Pathophysiology

Normally, the retinal pigment epithelium is able to maintain adhesion with the overlying neurosensory retina through a variety of mechanisms. These mechanisms include active transport of subretinal fluid and interdigitation of outer segments and the retinal pigment epithelium microvilli. With retinal detachment, these mechanisms are overwhelmed leading to separation of the neurosensory (inner layers) retina from the retinal pigment epithelial layer.

Retinal detachment occurs when subretinal fluid accumulates between the neurosensory retina and the retinal pigment epithelium. This process can occur in three ways. One mechanism involves ocurrence of a break in the retina allowing vitreous to directly enter the subretinal space. This is known as a rhegmatogenous retinal detachment. Rhegmatogenous retinal detachments are often due to retinal tears associated with posterior vitreous detachment or trauma.

Although this monograph focuses on rhegmatogenous retinal detachment, it is pertinent to note the other major causes of retinal detachment. A second mechanism involves proliferative membranes on the surface of the retina or vitreous. These membranes can pull on the neurosensory retina causing a physical separation between the neurosensory retina and retinal pigment epithelium. This is called a traction retinal detachment. Tractional retinal detachments can be seen in proliferative retinopathy due to diabetic disease, sickle cell and other disease processes leading to neovascularization of the retina. Tractional retinal detachments can also be due to proliferative vitreoretinopathy after trauma or surgery. The third mechanism for retinal detachment is due to accumulation of subretinal fluid due to inflammatory mediators or exudation of fluid from a mass lesion. This mechanism is known as a serous or exudative retinal detachment. Serous detachments are caused by a number of inflammatory, or exudative retinal disease processes such as Sarcoidosis or choroidal neoplasms. Serous retinal detachments may also be the presenting sign in patients with aggressive metastatic cancer, such as testicular cancer.[5]

Primary prevention

Patients with known risk factors for retinal detachment should have serial dilated fundus examinations with scleral depression, often yearly. Protective eyewear is recommended for individuals with high myopia that participate in contact sports. Patients undergoing cataract surgery should be counseled about the importance of reporting symptoms of retinal tears and detachments.

Diagnosis

History

Patients who present with symptoms of new onset significant photopsias and/or persistent new floaters should be suspected of having a retinal tear, which could lead to a retinal detachment. A patient with constant fixed or slowly progressive visual field loss should be suspected of having a detachment until proven otherwise. Important information in the history includes onset of symptoms, presence and duration of decreased central visual acuity, prior trauma, prior surgery, hemorrhage, and a complete past medical history and review of systems.

Physical examination

Visual acuity, pupillary examination, visual field testing and intraocular pressure measurement are important parts of the predilated ophthalmic examination to evaluate patients with symptoms of retinal detachment. Additional examination to include color vision in the visual field.

Slit lamp examination of the anterior segment should be completed prior to dilation. Examination of the anterior vitreous for pigment (Schaffer's sign) or vitreous hemorrhage is critical. A thorough fundus examination to include indirect ophthalmoscopy with scleral depression and visualization to the ora serrata should be completed. A detailed drawing describing the detachment with location of retinal pathology may be documented.

If there is no view to the posterior pole such as in hemorrhage or media opacity, B-scan ultrasound should be used to evaluate the retinal and vitreous status.

Clinical diagnosis

Rhegmatogenous retinal detachment has a characteristic appearance differentiating it from a tractional or serous detachment. A rhegmatogenous retinal detachment has a corrugated appearance and undulates with eye movements. Tractional detachments have smooth concave surfaces with minimal shifting with eye movements. Serous detachments show a smooth retinal surface and shifting fluid depending on patient positioning. In the vast majority of cases, a retinal break will be identified with proper examination, thus confirming a rhegmatogenous retinal detachment. Without visualization of a retinal break, the diagnosis of rhegmatogenous retinal detachment should be questioned, however there are cases where the retinal break is obscured by vitreous hemorrhage or other media opacities; alternativly, occasionally the offending retinal breaks are too small to visualize.

Laboratory/Ancillary testing

Rhegmatogenous retinal detachment is a clinical diagnosis. Where available, it is sometimes appropriate to examine and document macula status with ocular coherence tomography and/or wide field fundus photography. Additionally, in cases of media opacities, B-scan ultrasound is indicated and may be a critical diagnostic tool.

Laboratory testing is typically only indicated in traction or exudative detachments. If a cause for the traction retinal detachment cannot be determined by history, further laboratory analysis may be required to determine if diabetes, sickle cell, carotid disease or another systemic or ocular process is the source for proliferative retinopathy. Since exudative detachments may be due to a systemic or ocular inflammatory process, laboratory investigation may be indicated. In these cases, fluorescein angiography may be indicated to further clarify exudative processes such as macular degeneration, central serous chorioretinopathy, and Vogt-Koyanagi-Harada syndrome or other uveitic processes. Ultrasound is a useful imaging modality to evaluate choroidal masses or posterior scleritis.

Differential diagnosis

The differential diagnosis of retinal detachment includes retinoschisis, choroidal mass. Rhegmatogenous retinal detachment is most often confused with retinoschisis and serous retinal detachment. Retinoschsis can be distinguished from retinal detachment by appearance on ultrasound, uptake of photocoagulation with retinoschisis, and absolute with retinoschisis versus relative scotoma in retinal detachment. Choroidal masses can be distinguished from retinal detachment by observing the characteristics of imaging with ultrasound.

Management

General treatment

Once a retinal detachment has been identified, one must determine what type of detachment is present. Surgical management is indicated for rhegmatogenous and tractional detachments.

For rhegmatogenous detachments, all retinal breaks should be identified, treated and closed. Techniques for repair include pneumatic retinopexy, scleral buckle or vitrectomy, or combinations of these techiques.

  1. Pneumatic retinopexy involves the injection of an intraocular gas bubble along with retinopexy using cryotherapy or laser., typically in a clinic setting. An important part in the successful repair of retinal detachment with pneumatic retinopexy involves head positioning so that the gas bubble tamponades the retinal tear. Pneumatic retinopexy is typically only used with retinal detachments due to retinal tears in the superior eight clock hours and involving a single break less than one clock hour., although exact criteria are controversial and largely depend on surgeon and patient factors.
  2. Scleral buckles are silicone bands permanently placed around the outside of the globe under the extraocular rectus muscles to relieve any traction and support retinal tears. Scleral buckling is combined with retinopexy, typically cryotherapy. This is the oldest method of repair and still has excellent results in well-trained hands. This procedure is performed in the operating room.
  3. Pars plana vitrectomy with 20 gauge, 23 gauge, 25 gauge, or 27 gauge instruments involves removal of the vitreous by way of cutting the vitreous strands with a vitrectomy machine/handpiece and flattening of the retina through a direct intraocular process.


In tractional detachments, tractional elements (usually epiretinal or subretinal membranes) must be relieved. This is typically accomplished with pars plana vitrectomy, but may be combined with scleral buckling as an adjunct.

For serous detachments, management is nonsurgical. Any inflammatory disease or underlying mass should be identified and treated if possible.

Complications

Proliferative retinopathy (PVR) is the most common cause of repair failure and occurs in about 8–10% of patients undergoing primary retinal detachment repair. [6] [7] Risk factors for PVR include:

  1. Age
  2. Giant retinal tears
  3. Retinal detachments involving more than 2 quadrants
  4. Previous retinal detachment repair
  5. Use of cryotherapy
  6. Vitreous hemorrhage
  7. Choroidal detachment.


PVR requires surgical intervention to release the traction caused by membranes and has a poor visual prognosis.[8]

Additional Resources


References

  1. Haimann MH, Burton TC, Brown CK. Epidemiology of retinal detachment. Arch Ophthalmol. Feb 1982; 100(2):289-92.
  2. Go SL, Hoyng CB, Klaver CC. Genetic risk of rhegmatogenous retinal detachment: a familial aggregation study. Arch Ophthalmol. 2005; 123: 1237-41.
  3. Gonin J. Treatment of detached retina by searing the retinal tears. Arch Ophthalmol 1930;4:621-625.
  4. Lewis H. Peripheral Retinal Degenerations and the Risk of Retinal Detachment. Am J Ophthalmol 2003; 136:155–160.
  5. Phelps, P. O., et al. "Metastatic mixed germ-cell neoplasm presenting as retinal detachment." Journal of clinical oncology: official journal of the American Society of Clinical Oncology 30.13 (2012): e133.
  6. Brucker AJ, Hopkins TB. Retinal Detachment Surgery: The Latest in Current Management. Retina. 2006; 26: S28-S33.
  7. Leaver PK. Proliferative vitreoretinopathy. Br J Ophthalmol. 1995 October; 79(10): 871–872.
  8. Girard P, Mimoun G, Karpouzas I, et al. Clinical risk factors for proliferative vitreoretinopathy after retinal detachment surgery. Retina. 1995; 14:417–424.