A 68-year-old pilot presents 2 months after uncomplicated cataract surgery with insertion of a Crystalens IOL OD. He states that his vision is blurry and he is having more difficulty reading. His uncorrected vision is 20/60 at distance and J10 at near OD, and manifest refraction of +1.00+0.50x40 yields 20/20 and J6 acuity. Old records indicate that one month previously, his uncorrected vision in that eye was 20/15 and J3. Anterior segment exam reveals a clear cornea, quiet anterior chamber, well-positioned IOL, and mild posterior capsular opacity. Posterior segment exam is normal. The macula is flat with a sharp foveal reflex.
The diagnosis and treatment of posterior capsular opacification is discussed with the patient and he elects to undergo Nd:YAG laser posterior capsulotomy two days later. One week after the laser procedure, the patient reports clear vision and is happy. His uncorrected visual acuity is 20/20+2 and J3, BSCVA is 20/15 with a refraction of plano+0.25x45, and ocular exam is normal.
The patient calls the following week to say that his vision seems foggy again and he needs to wear magnifying glasses. On exam, his vision is 20/20-2 and J5. Anterior segment exam is normal but the dilated fundus exam shows loss of the foveal reflex. An OCT is performed and shows the following:
The patient has developed cystoid macular edema and is treated with a topical steroid and NSAID. One month later, he is pleased to report that the vision has improved. His uncorrected visual acuity is 20/20+2 and J3, and the macula appears flat. Follow up OCT shows almost complete resolution of the CME:
The patient is told to slowly taper the steroid drop, continue the NSAID, and return in another month for reexamination.
Discussion - This case illustrates several important points:
- Subtle ocular abnormalities (i.e., tear film, PCO, CME) can have a large impact on visual function in patients with presbyopia-correcting IOLs. In this case, the mild PCO caused the patient’s symptoms. Capsular contraction resulted in a hyperopic shift, but even though the best-corrected distance vision was only slightly affected, the PCO significantly reduced his near vision.
- Opening the posterior capsule during the early postoperative period after cataract surgery increases the risk of CME. This patient had a normal retinal exam 2 months after cataract surgery, but he developed CME shortly after undergoing laser posterior capsulotomy. Patients who choose presbyopia-correcting IOLs expect excellent vision and usually do not want to wait several months for treatment if they develop a PCO soon after cataract surgery. If a posterior capsulotomy is performed early, the risk of CME must be discussed and consideration should be given to prophylaxis with a topical NSAID ± steroid.
- When CME is diagnosed, appropriate treatment must be instituted and the patient followed closely. If the CME does not respond to initial topical therapy, then referral to a retinal specialist for additional treatment is recommended.