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OP8.1-6 | Lens, Cataract and Aphakia — PBL Case

CLINICAL SETTING

Mr. Ramaiah, a 68-year-old retired farmer from a rural district, arrives at the NPCBVI-sponsored cataract camp with his daughter. He reports that his vision has been failing in both eyes for the past three years, but he did not seek treatment earlier because he believed going blind was inevitable at his age. He now cannot identify faces at 3 metres and is no longer able to manage his daily activities independently. On examination: Right eye — visual acuity 2/60, slit-lamp shows a white, featureless lens with absent iris shadow. Left eye — visual acuity counting fingers at 1 metre, slit-lamp shows a swollen intumescent lens, IOP measured by Schiotz tonometer at 38 mmHg, and the anterior chamber is demonstrably shallow compared to the right eye. Corneal clarity: right eye good; left eye: mild haze. Fundal examination: right eye — normal optic disc and retina visible on indirect ophthalmoscopy; left eye — posterior segment not visible. Mr. Ramaiah's daughter explains that he also takes medication for blood pressure (which he stopped two months ago) and has been having headaches. A camp nurse takes his BP: 182/108 mmHg. Blood glucose (glucometer) is 11.4 mmol/L. He has no known drug allergies. The ophthalmologist leading the camp must decide within the next two hours whether to list Mr. Ramaiah for surgery today, defer, and if surgery proceeds, plan the operative and postoperative strategy.

Trigger 1: What is happening in each eye — and which eye is the emergency?

The camp ophthalmologist has 10 minutes to assess Mr. Ramaiah before the surgical list is finalised. She performs a systematic examination and notes: right eye mature cataract (absent iris shadow, white lens, IOP normal); left eye intumescent lens with raised IOP, shallow AC, and corneal haze. She asks the IMG student on the camp to give a rapid clinical summary.

DISCUSSION POINTS

  • Classify the cataract in each eye by stage of maturation, citing the specific clinical signs that support your classification.
  • Explain the pathophysiological mechanism that is causing the raised IOP and shallow anterior chamber in the left eye. Name this complication and explain why it is a surgical emergency.
  • What does the absent fundal view in the left eye tell you, and how does it influence surgical planning?
  • The ophthalmologist considers the iris shadow test. Describe how this test is performed and what each result means for cataract staging.
  • If you had to prioritise one eye for surgery today, which would you choose and why? Consider both the severity of the ocular complication and the systemic findings.
Click to reveal Trigger 2: Systemic fitness, surgical technique, and preoperative counselling (discuss previous trigger first!)

Trigger 2: Systemic fitness, surgical technique, and preoperative counselling

The ophthalmologist decides the left eye must be operated today given the acute lens-induced glaucoma. She asks the team to address Mr. Ramaiah's systemic findings and prepare him for surgery. BP 182/108 mmHg, blood glucose 11.4 mmol/L. The camp facility has no phacoemulsification machine. The consent discussion now needs to happen — Mr. Ramaiah speaks only Telugu and the camp interpreter is available. His daughter says he is frightened and has heard that eye operations can leave a person completely blind.

DISCUSSION POINTS

  • The ophthalmologist must make a decision: operate today with BP 182/108 mmHg, or defer? What is the accepted BP threshold for proceeding with cataract surgery under local anaesthesia? What measures could be taken at the camp to allow safe proceeding?
  • Which surgical technique should be used, given that the camp facility has no phacoemulsification machine? Compare phacoemulsification, MSICS, and ECCE for this setting and patient.
  • Describe the steps of extracapsular cataract extraction (ECCE) in sequence. What is the critical step that, if mishandled, leads to the most feared intraoperative complication?
  • What type of anaesthesia would you recommend for this patient? Compare retrobulbar, peribulbar, sub-Tenon's, and topical anaesthesia — which provides the best akinesia and why is that important for ECCE?
  • Conduct a structured counselling discussion with Mr. Ramaiah, in simple language. How would you explain: (a) what a cataract is; (b) what the operation involves; (c) the risk that he may not regain full vision in the left eye due to corneal haze and the unknown posterior segment; (d) the postoperative regimen; (e) warning signs requiring urgent return. How would you address his fear of total blindness?
  • Identify the intraoperative complication he would be at highest risk for given his intumescent lens, and describe how it is recognised and managed.
Click to reveal Trigger 3: Postoperative course and long-term rehabilitation (discuss previous trigger first!)

Trigger 3: Postoperative course and long-term rehabilitation

Mr. Ramaiah undergoes successful MSICS of his left eye, with PMMA IOL implantation. Postoperatively, his vision is 6/18 with the left eye — slightly limited by residual corneal haze. He is discharged with topical medications. One week later, he attends a follow-up camp: he is happy with his left eye vision. Examination of the right eye is also performed: slit-lamp shows the white mature cataract. The surgeons propose right eye ECCE in 4 weeks. Three years later, Mr. Ramaiah returns: right eye vision has deteriorated to 6/36 despite uncomplicated right eye ECCE and good immediate postoperative outcome. Slit-lamp shows a hazy, wrinkled posterior capsule behind the IOL. He is anxious — he thinks his cataract has come back and he will need another big operation.

DISCUSSION POINTS

  • What is the most likely cause of Mr. Ramaiah's right eye visual deterioration 3 years after successful cataract surgery? Name the condition, explain its pathogenesis (which cells, which mechanism), and state how common it is.
  • What is the correct treatment for this condition? Describe the procedure, and specifically address Mr. Ramaiah's anxiety — will he need another surgical operation?
  • Mr. Ramaiah also asks whether he should consider an IOL for his left eye if it ever needs surgery again (hypothetical). Discuss the management of aphakia: list all optical correction options, their respective advantages and disadvantages, and the specific reason spectacle correction is contraindicated in unilateral aphakia.
  • The NPCBVI programme and cataract camps represent a public health response to cataract blindness. What is India's rank globally in cataract-related blindness burden? What is the IMG's specific role in a cataract camp from the preoperative checklist to postoperative surveillance? Include: mydriasis protocol, consent checking, wrong-eye prevention, and complication recognition.
  • Across Mr. Ramaiah's entire clinical journey, list the lens-induced complications of cataract that you have encountered or discussed. For each, describe the mechanism and the definitive management.

Learning Issues

Research these questions and bring your findings to the discussion.

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