I have been a cataract surgeon for over a decade now, and with that experience, I am usually fairly accurate in my clinical assessment of how well my patient will fare after surgery. Occasionally I am surprised myself by the outcomes, just like I was on a case I operated on last week.
Mdm C is not your typical patient. She presented to me with poor vision in the right eye, and on examination she did indeed have a cataract in that eye. However, she was also markedly short sighted in that eye, and had been so since childhood. Her spectacle degree in that eye was 750 degrees, with astigmatism of 225 degrees. Her vision was perfect in the left eye without glasses. Due to the large imbalance between spectacle degrees of both eyes, she had lived her life without glasses and relied heavily on the left eye, and had lived with poor vision in the right eye for decades.
In this case, there is a high chance that she has developed a lazy eye in the right eye. In childhood, vision must be good in both eyes in order for pathways between the eye and brain to develop normally. If vision is better in one eye, the poorer eye will become “lazy” and the pathways to the brain will not develop normally. This is a condition known as amblyopia. Pathways mature when a child reaches the age of 8, and beyond that age, the vision in the lazy eye cannot be improved.
In Mdm C’s case, I felt that the likelihood was high that she had amblyopia in the right eye, as she had been highly short sighted in that eye all her life. As a result, even with cataract surgery, I felt her vision would not be as good as her left eye.
I discussed this at length with her and her son, explaining to them the benefits and risks of cataract surgery, as well as my concerns that her vision would not be perfect in the right eye even after surgery. However, as her vision in the right eye was very poor, she decided to proceed with surgery despite the guarded prognosis. Her vision was 6/120- she was only able to see the biggest letter on the chart.
Surgery proceeded uneventfully. I removed the cataract and implanted a toric intraocular lens in the right eye, which corrects for both short sightedness as well as astigmatism.
She returned for review on the first postoperative day. When I opened her chart, I thought I had the wrong patient. Her vision in the right eye was 6/6- perfect vision!
Mdm C was ecstatic. She had not seen well in the right eye for decades as it had always been highly short sighted, and had never worn glasses or contact lenses in that eye. For the first time in her life, she had good vision in both eyes.
I had been wrong about my assessment that she had a right lazy eye- and I had never been so happy to have made a misdiagnosis.
I am always delighted when my patients achieve good outcomes, there is nothing more satisfying to me than restoring vision to my patients. When outcomes exceed expectations, I can only be humble and grateful, to God for whom nothing is impossible, and to my patients, for putting their faith in me, and giving me the privilege of being their cataract surgeon.