Retina, Part 2: Retinal Detachment

Educational Objectives

The goal of this program is to improve management of retinal detachment. After hearing and assimilating this program, the clinician will be better able to:

1. Identify risk factors that lead to development and progression of retinal detachment.
2. Differentiate rhegmatogenous retinal detachment from other forms of retinal detachment.
3. Estimate the location of retinal breaks associated with retinal detachment.
4. Develop strategies for surgical management of retinal detachments.
5. Determine urgency of surgery based on the macular status and duration of retinal detachment.

Summary

Epidemiology: lifetime risk for retinal detachments (RDs) is approximately 1 in 300; annual incidence ranges from 7 to 13 per 100,000 individuals; current rate of RD after cataract surgery is <1% but is ≈5% if anterior vitrectomy is performed and ≈10% if retained lens material is present; 1994 study of the Medicare population found that the 5-yr incidence of RD after cataract surgery is ≈1%

Risk factors for RD after cataract surgery: include male sex, younger age, myopia, and posterior capsular tears; previous studies found a risk for RD of 1% to 3% after yttrium-aluminum-garnet (YAG) laser capsulotomy, although the risk is likely <1% with current instrumentation; the strongest risk factor for RD (≈15%) is a prior RD in the fellow eye; risk for RD when lattice degeneration is present is approximately double that of RD without lattice degeneration; 20% of RDs appear to have an association with lattice degeneration; high myopia increases the risk for RD

Presenting features: symptoms — include photopsia and floaters, which may represent posterior vitreous separation rather than the actual RD; a curtain in the vision corresponds with the area of the RD; ≈50% of RDs that develop after cataract surgery occur <1 yr; location — with previous techniques of intracapsular cataract surgery, the vitreous base was the most common location for a retinal tear; with current techniques, most tears occur anterior to the equator; studies show that ≈50% of patients with RD have multiple breaks; involvement of the macula is the most important prognostic factor and occurs in approximately one-third of cases; the superior quadrant is most commonly involved; study by Alio found that patients with high myopia (defined as ≥6 D or axial length of ≥26 mm) who underwent phacoemulsification had a risk for RD of 2.7% (risk was 3.7% in patients <50 yr of age); patients with YAG capsulotomy or posterior capsular ruptures did not have an increased risk

History: RDs were previously recognized with the direct ophthalmoscope, which was introduced by Helmholtz in 1851; Gonin postulated that retinal tears caused RDs and suggested that sealing these tears may resolve the RD; Gonin also introduced ignipuncture, which involved estimating the location of the tear via direct ophthalmoscopy and transconjunctivally cauterizing the tear

Pathogenesis: persistent traction on a retinal tear allows fluid to enter underneath the retina, which leads to RD; subretinal fluid is highly proteinaceous and thus has a high specific gravity, which accelerates detachment of the retina; fluid currents in the vitreous cavity also affect the rate of detachment; patients with previous vitrectomy are at higher risk for rapid progression of RD

Natural history: symptomatic RD — defined by symptoms of flashes and floaters or visual field (VF) cuts; risk for progression is higher if the VF cut is progressive or correlates with a superior RD; the urgency to treat the RD is greater if the macula is intact; asymptomatic RD — typically nonprogressive; study by Brod followed 31 eyes for 6 mo to 12 yr; 25 RDs in the study had atrophic holes, 6 eyes had horseshoe tears (HSTs), and only 2 eyes progressed to require scleral buckling procedures; however, atrophic holes are likely not associated with true rhegmatogenous RDs, suggesting that patients may have had small HSTs that were unrecognized; study by Cohen that followed 18 asymptomatic RDs for a mean of 46 mo found that only one RD became slightly enlarged

Chronic nonprogressive RD: has a demarcation line (typically arcuate shaped) following the posterior margin of the RD that represents a chorioretinal scar and takes ≈3 mo to form; a new retinal break may occur near a previously demarcated RD; cysts may develop in the retina and resolve once the RD is repaired

Differential diagnosis: tractional or exudative RD must be ruled out; tractional RDs have a preretinal component; exudative RD has thick fluid that shifts and changes configuration of the RD with changes in posture (fluid may take 1-2 min to shift); findings that increase suspicion for rhegmatogenous RD include symptoms of flashes and floaters, a progressive shadow in the vision, pigment in the vitreous, posterior vitreous detachment, vitreous hemorrhage, hydration lines, and retinal breaks

Diagnosis: important to identify a shallow area of detachment, particularly if the shallow area involves the macula; scleral indentation is the standard method of examining the peripheral retina; however, tears can often be seen without scleral indentation; mirrored contact lenses can also locate retinal breaks; retinal drawings assist with visualizing the indirect or “flipped” view of retina and provide a systematic way of viewing each meridian of the retina; retinal vessels can be used as landmarks to map out the distribution of the detachment

Locating retinal breaks: configurations may be categorized as superior, inferior, or lateral; bullous RDs are generally seen in superior tears; if a bullous RD is found inferiorly, a trough of subretinal fluid is often found coming from a superiorly located HST; RDs from an inferior break are usually shallow; retinal tears are generally located posterior to the most anterior extent of vitreous separation (ie, more posterior than the ora serrata)

Lincoff rules: the pathogenic break is located within one clock hour of 12 o’clock in ≈90% of superior RDs; with inferior RDs that extend superiorly in an asymmetric fashion, 90% of breaks are located within 1 to 2 clock hours of the uppermost limit (eg, detachment that extends to 1 o’clock on one side and 9 o’clock on the other side is most likely to have a break between 1 and 3 o’clock); if an inferior RD is symmetric around the 6 o’clock position, the break is likely to be located within 1 to 2 clock hours of 6 o’clock; if an inferior RD is quadrantic (5 to 9 o’clock), the break is most likely to be located on the 6 o’clock side (closer to the uppermost extent)

Clinical pearls: use of a T-shaped scleral depressor, with an emphasis on making motions anterior to posterior, allows for better visualization of the flap in a HST; look for retinal pigment epithelial (RPE) changes underlying the tear and evidence of vitreous traction; tears are located at or posterior to the area where the vitreous is attached; because blood travels inferiorly due to gravity, look for a pathogenic break at the margin of the hemorrhage (as opposed to within the hemorrhage)

Treatment

Objectives: include closing the break, relieving traction to prevent extension of the tear and recurrence of breaks, tamponading the break, and performing internal drainage with vitrectomy

Scleral buckle: the concept of a scleral buckle without external drainage was introduced by Custodis in 1949; in the 1950s, Schepens pioneered additional techniques; goal is to neutralize traction at the vitreous base by reapproximating the RPE to the retina and redirect fluid currents; use in clinical practice has decreased due to complications

Intraoperative complications: include scleral perforation, rupturing of muscles, subretinal hemorrhage, and occlusion of the central retinal artery

Postoperative complications: early — include pain, inflammation, choroidal effusion, and elevated intraocular pressure; choroidal effusion may resolve on its own, but excessively high scleral buckles should be avoided to reduce risk; RD may persist with a missed break, inadequate vitreous removal, inadequate or misplaced scleral buckle, or increased cellular proliferation (eg, proliferative vitreoretinopathy); late — include refractive changes (2 to 3 D of myopia are typically introduced), extraocular muscle imbalance (2% to 3% of cases), or extrusions caused by buckle infections (2% to 3% of cases)

Transitions to nonbuckling procedures: Lincoff balloon procedure provided proof of concept that temporary buckling was more important than a permanent buckle and led to the idea that vitrectomy alone may be effective for treatment of RDs; in 1983, Rosengren introduced the concept of an internal gas tamponade in conjunction with drainage of subretinal fluid, and other modifications included use of long-acting gases and silicone oil for tamponade

Pneumatic retinopexy (PR): Kreissig described the use of a gas bubble with cryopexy in 1979; previously, cryopexy was reserved for postoperative use if the RD failed to close

Studies: in 1987, Hilton described successful reattachment of RD with PR alone in 84 of 100 patients; randomized trial in 1989 — found success rates of 82% with scleral buckle and 73% with PR; PIVOT trial — found success rates at 1 yr of 81% with PR and 93% with vitrectomy; patients reported less distortion with PR; study by Yannuzzi — review of 9553 patients who underwent PR in the IRIS registry found a success rate of 68%; 3 patients developed endophthalmitis, which is similar to the rate observed with vitrectomy

Advantages: include low cost, short procedure time, ability to perform in the office, and possibly better visual acuity (although this may be related to patient selection)

Disadvantages: include slightly lower success rate, requirement for stringent positioning during the procedure, and higher learning curve on the part of the surgeon

Indications: ideal candidates are phakic patients who have a defined single superior break, are not myopic, have clear media, and do not have glaucoma (gas expansion may increase intraocular pressure)

Technique: involves injecting gas and using laser or cryopexy to create chorioretinal scars; an advantage of cryopexy is that it can be performed during injection of the gas bubble; laser is performed a few days after the gas has expanded

Vitrectomy

History: first introduced by Dodo in 1951; Haruta described a closed vitrectomy in 1959; Kasner developed the open-sky technique in 1968; in 1971, Machemer and Parel reported on development of practical instrumentation, eg, device for vitreous infusion suction cutter, that formed the basis for modern instrumentation and systems; recent developments used in modern vitrectomy include endolaser, perfluorocarbon liquids, intraoperative optical coherence tomography to delineate macular pathology, chromovitrectomy to facilitate membrane removal, and smaller-gauge instrumentation

Use for RD: previously, vitrectomy was reserved for moderate to severe proliferative vitreoretinopathy, reoperations, posterior breaks in which scleral buckling was inappropriate, media opacities, and giant tears; standard of care for primary RD has evolved to use of vitrectomy with or without a scleral buckle

Advantages: eliminates complications of scleral buckle (eg, refractive error, strabismus, and extrusion), allows the surgeon to maintain more control, and is faster

Disadvantages: complications include additional tears, development of cataracts, and hemorrhages; stringent positioning is needed because gas bubbles are typically used; procedure is expensive

Vitrectomy vs scleral buckle: 2006 meta-analysis of surgical repair of pseudophakic RDs — included 1579 scleral buckle, 457 vitrectomies, and 194 combined procedures; age, macula-off status, and degree of preoperative proliferative vitreoretinopathy were similar across procedures; rate of anatomic success was highest with combination procedures and lowest with scleral buckle alone; 2006 study by Weichel — rates of anatomic success were similar between vitrectomy only and a combination of vitrectomy and scleral buckle; take-home messages — current data show that vitrectomy with scleral buckle is superior to scleral buckle alone, and vitrectomy alone has a similar or better rate of success compared with scleral buckle alone

Prognosis: preoperative visual acuity is the strongest predictor of postoperative visual acuity and is largely determined by macula-on or -off status; longer duration of detachment is associated with poorer prognosis and lower likelihood of anatomic success; success is slightly better in phakic patients than in pseudophakic patients; increased size or number of breaks is associated with poorer prognosis; anatomic success of scleral buckle alone ranges from 85% to 90%

Macular involvement: visual success is slightly higher in macula-on cases; Ross showed that the height of the macula detachment is an important factor for determining anatomic success; macula-on vs macula-off status — Tani found that approximately one-third of patients with macula-off RDs and 85% of those with macula-on RDs recovered visual acuity of 20/50 or better; duration of macular involvement and visual acuity — relationship is unclear; 2002 study by Hassan found no association with final visual acuity if the duration of macular involvement was ≤10 days; Gundry indicated that the poorest prognosis was observed after ≥2 mo of macular involvement; Tani found poorer visual prognosis if the macula was off for >1 mo

Timing of surgery: 1992 study by Hartz compared 48 eyes that received same-day surgery with 89 eyes that were scheduled for surgery 1 to 2 days after presentation of RD; none of the macula-on cases that underwent scheduled surgery progressed to macula-off RDs; the authors concluded that scheduling surgery within 1 to 2 days did not yield a poorer prognosis; speaker’s study showed similar results, along with higher health care and opportunity costs with emergent surgery

Considerations: macula-on status, better preoperative visual acuity, and smaller area of detachment are key prognostic factors for anatomic and visual success; macula-on RDs should be treated as soon as possible (within 1 to 2 days); macula-off RDs are urgent but less emergent than macula-on cases; a superior macula-on RD progresses more rapidly than an inferior macula-on RD and warrants more urgent surgery; RD is primarily caused by HSTs, which are usually commensurate with the onset of symptoms; however, asymptomatic HST may not require treatment; once RD develops, consider risk factors, extent of RD, and progression of RD to determine urgency of surgery

Readings

Brown K, Yannuzzi NA, Callaway NF, et al. Surgical outcomes of rhegmatogenous retinal detachment in young adults ages 18-30 Years. Clin Ophthalmol. 2019 Oct;13:2135-2141; Clark A, Morlet N, Ng JQ, et al. Risk for retinal detachment after phacoemulsification: a whole-population study of cataract surgery outcomes. Arch Ophthalmol. 2012 Jul;130(7):88; Echegaray JJ, Vanner EA, Zhang L, et al. Outcomes of pars plana vitrectomy alone versus combined scleral buckling plus pars plana vitrectomy for primary retinal detachment. Ophthalmol Retina. 2021 Feb;5(2):169-175; Gonzalez MA, Flynn HW Jr, Smiddy WE, et al. Surgery for retinal detachment in patients with giant retinal tear: etiologies, management strategies, and outcomes. Ophthalmic Surg Lasers Imaging Retina. 2013 May-Jun;44(3):232-237; Joye AS, Bhisitkul RB, Pereira DDS, et al. Rhegmatogenous retinal detachment masquerading as exudative panuveitis with intense anterior chamber inflammatory reaction. Am J Ophthalmol Case Rep. 2020 Jun;18:100618; Kim JD, Pham HH, Lai MM, et al. Effect of symptom duration on outcomes following vitrectomy repair of primary macula-off retinal detachments. Retina. 2013 Oct;33(9):1931-1937; Lee CS, Shaver K, Yun SH, et al. Comparison of the visual outcome between macula-on and macula-off rhegmatogenous retinal detachment based on the duration of macular detachment. BMJ Open Ophthalmol. 2021 Mar;6(1):e000615; Papakostas TD, Vavvas D. Postoperative complications of scleral buckling. Semin Ophthalmol. 2018;33(1):70-74; Salicone A, Smiddy WE, Venkatraman A, et al. Management of retinal detachment when no break is found. Ophthalmology. 2006 Mar;113(3):398-403; Saxena S, Lincoff H. Finding the retinal break in rhegmatogenous retinal detachment. Indian J Ophthalmol. 2001 Sep;49(3):199-202; Schmidt I, Plange N, Rößler G, et al. Long-term clinical results of vitrectomy and scleral buckling in treatment of rhegmatogenous retinal detachment. ScientificWorldJournal. 2019;2019:5416806; Sengillo J, Kunkler AL, Al-khersan H, et al. Long-term outcomes of fellow eyes in patients with non-traumatic rhegmatogenous retinal detachments due to giant retinal tears. Invest Ophthalmol Vis Sci. 2021 Jun;62(8):3108; Stewart S, Chan W. Pneumatic retinopexy: patient selection and specific factors. Clin Ophthalmol. 2018;12:493-502; Tornambe PE, Hilton GF. Pneumatic retinopexy. A multicenter randomized controlled clinical trial comparing pneumatic retinopexy with scleral buckling. The Retinal Detachment Study Group. Ophthalmology. 1989 Jun;96(6):772-784; Williams KM, Dogramaci M, Williamson TH. Retrospective study of rhegmatogenous retinal detachments secondary to round retinal holes. Eur J Ophthalmol. 2012 Jul-Aug;22(4):635-640; Yannuzzi NA, Li C, Fujino D, et al. Clinical outcomes of rhegmatogenous retinal detachment treated with pneumatic retinopexy [published online ahead of print, 2021 Jun 17]. JAMA Ophthalmol. 2021;139(8):848-853; Yoshida I, Shiba T, Hori Y, et al. Relationships between retinal break locations and the shapes of the detachments [published correction appears in Clin Ophthalmol. 2019 Oct 10;13:1997]. Clin Ophthalmol. 2018 Oct;12:2213-2222.

Disclosures

For this program, members of the faculty and planning committee reported nothing relevant to disclose.

Acknowledgements

Dr. Smiddy was recorded exclusively for Audio Digest on October 28, 2021. Audio Digest thanks Dr. Smiddy for his cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

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Lecture ID:

OP600301

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.