• Information
  1. Definition
  2. Rhegmatogenous
  3. Non-Rhegmatogenous
  4. Symptoms and Signs
  5. Treatment

A. Definition

1. Separation of retina from retinal pigement epithelium (RPE)
2. Blinding ocular condition if involves the macula
3. Subacute (rapidly progressive) cause of blindness
4. Mechanisms of RD
   1. Rhegmatogenous
   2. Exudative
   3. Traction

B. Rhegmatogenous (Intrinsic)

1. Retinal break allows liquid vitreous to track subretinally leading to RD
   1. 1:10-15,000 per year develop RD
   2. Overall, 6% of all eyes have some kind of break
2. Syneresis - Breakdown of Vitreous
   1. Type II collagen fibril decomposition
   2. Formation of liquified pockets
   3. Collapse of Gel Pocket (Vitreous Structure)
   4. Fluid can track under reintal break
3. Breaks can occur due to trauma or vitreous traction on retina
4. Posterior vitreous detachment (PVD)
   1. Consists of sudden collapse of vitreous by syneresis
   2. Vitreous gel pulls on areas of firm attachment, such as vitreous base
   3. Traction occurs mainly along vessels or scars and leads to breaks
   4. Certain conditions predispose to PVD: cataract surgery, axial myopia
   5. Certain lesions are more prone to breaks due to traction
   6. These include lattice degeneration, vitreoretinal tufts, peripheral retinal lesions

C. Non-Rhegmatogenous (Extrinsic)

1. Main Types
   1. Exudative (Serous)
   2. Tractional
2. Exudative Detachment
   1. Accumulation of fluid under retina due to leaky vessels or RPE abnormalities
   2. Neoplasia or inflammation
   3. Hypertension or pre-eclampsia
3. Tractional Detachment
   1. Proliferative retinopathy such as Diabetes
   2. Post-surgical or post-penetrating injury

D. Symptoms and Signs

1. Early symptoms
   1. Floaters due to condensation of vitreous gel / pigmentary debris or blood in vitreous
   2. Light flashes ("photopsia") due to traction (tugging) on retina
   3. Around 15% of patients with acute symptomic PVD will have retinal tear
   4. ~70% of patients with symptoms of PVD and vitreous hemorrhage have retinal tare
   5. Anywhere from 25-90% of symptomatic tears progress to RD
2. Progression to Visual Field Loss
   1. Shadow or Veil in field of Vision
   2. Macular Detachment leading to sudden severe reduction of visual acuity
3. Examination of Rhegmatogenous RD
   1. Whitened, corrugated retinal appearance
   2. Undulation with movement; may have fixed folds
4. Examination of Exudative RD
   1. "Shifting fluid" depending on position
   2. Smooth appearance with fixed folds
5. Examination of Tractional RD
   1. Smooth immobile surface
   2. Concave relative to front of eye

E. Treatment

1. Retinal breaks without Detachment
   1. Goal is prophylactic treatment to prevent RD and includes:
   2. Laser Photocoagulation - posterior tears
      1. Cryotherapy - anterior tears
      2. Both methods allow formation of firm chorioretinal adhesion (scar)
   3. Retinal break sealed so that fluid cannot enter subretinal space
   4. Scarred retina without function, but usually in periphery without noticable scotoma
2. Rhegmatogenous RD Surgery
   1. Surgical Goals: find and seal all breaks and reposition retina
   2. Usually scleral buckling: bring eyeball (sclera) in contact with retina after breaks sealed
   3. May need to drain subretinal fluid to escape via scleral incision
   4. Prognosis depends on whether macula detached preoperatively
   5. 87% with macula spared achieve 20/50 or better
      1. 37% with macula involved achieve 20/50 or better
3. Exudative RD
   1. Diagnose and/or manage underlying condition
   2. Usually resolve without surgery
4. Tractional RD
   1. Requires vitrectomy to relieve vitreous traction on retina
   2. Mobilization and repositioning of retina
   3. Vitrectomy often performed through three ports in eye:
   4. Light port
      1. Irrigating cannula
      2. Instrument port

References

1. Aylward GW. 1996. Br J Hosp Med. 55(3):100
2. Kim RY, Loewenstein JI. 1998. Int Ophthalmol Clin. 38(1):177