Surgery on one eye might affect the other?
This was a fascinating… and disturbing… animal study. They made an incision on only one cornea (partway through the stroma) but BOTH eyes ended up affected, in terms of tear secretion, structural change and immune cell activation.
CONCLUSIONS:
The unilateral corneal nerve severing resulted in activation of the immune cells on the ocular surface and dysregulated lacrimal secretion bilaterally through the bidirectional neuronal signals. It suggests that the unilateral corneal nerve damage may alter immune homeostasis and mechanistically participate in the development of bilateral inflammatory disorders such as dry eye.
More: Bilateral Effect of the Unilateral Corneal Nerve Cut on Both Ocular Surface and Lacrimal Gland. Lee et al, IOVS, January 2019.
Dry eye after cataract surgery: symptoms vs signs
This abstract caught my eye because it was showing fewer dry eye symptoms but more clinical signs after cataract surgery, suggesting cataract surgery patients may need monitoring for dry eye even if they’re “feeling” okay.
The presence of subjective DE symptoms was generally inversely associated with cataract surgeries, whereas abnormal clinical tests were more pronounced among postsurgical cataract patients than among controls…. This study demonstrates the importance of evaluating ocular surface conditions in pseudophakic patients, even if they lack DE symptoms.
More: Discrepancies in Persistent Dry Eye Signs and Symptoms in Bilateral Pseudophakic Patients. Hanyuda et al, Journal of Clinical Medicine, February 2019.
Bandage contacts after cataract surgery
We’re seeing more and more studies about dryness after cataract surgery. This one suggests it may be useful to give bandage contact lenses for dry eye after surgery (as you might do for some corneal surgeries but not normally after cataract surgery).
I wonder if this is all about rising numbers of cataract surgery patients having pre-existing dry eye and therefore being more likely to be symptomatic after cataract surgery, in addition to improved education about dry eye and patients speaking up about it more.
A BCL can improve tear film stability and lessen dry eye discomfort immediately after phacoemulsification.
More: Efficacy of an ocular bandage contact lens for the treatment of dry eye after phacoemulsification. Chen et al, BMC Ophthalmology, January 2019.
Meantime, in the post-LASIK ectasia world….
Corneal ectasia has emerged as a serious complication of laser vision correction… its prevention has become a major concern for refractive surgeons.
Here we are, 20 years later and yes, ectasia is still an issue although apparently less so than in the past. Now, as then, I struggle with the ethics of offering an elective surgery on perfectly healthy corneas when a complication with such serious ramifications is still so difficult to understand or predict.
Nevertheless, mysterious cases of ectasia still challenge the field and stimulated research in this field…. Artificial intelligence (AI) and machine-learning algorithms may play a definitive role for further enhancing ectasia risk assessment. Reporting ectasia after LVC is needed.
More: Post-LASIK Ectasia: Twenty Years of a Conundrum. Ambrosio R Jr. Seminars in Ophthalmology. January 2019.