Dear Editor,
We thank Dr. Davide Romano for his interest and comment on our video journal.
Corneal immune privilege is a phenomenon that is tightly bound to angiogenic privilege because the blood as well as lymphatic vessels constitute the afferent and efferent arms of an immune response arc.[1,2]
The technique of fine needle diathermy as described by Pillai et al. was applied to occlude both afferent and efferent vessels with equal efficacy. When afferent and efferent vessels are located close to each other, they can be occluded simultaneously with a single pass of the needle which also reduces intrastromal bleeding.[3]
Cursiefen et al. have reported that angiogenesis and lymph angiogenesis may be triggered by an identical pathophysiological process, grow in parallel, but regress over different time frames. Simultaneous occlusion of afferent and efferent vessels helps in faster resolution of lymphatics which are part of the afferent immune arm.[4,5]
Using the lowest cautery setting, coagulating multiple transverse vessels with transverse pass of the needle, avoiding areas of corneal thinning, attention to epithelial healing, and postoperative inflammation control have all been described in the video. These measures are meant to mitigate the thermal and inflammatory effects of the procedure, and we have found good results consistently.
Lastly, the simplicity, low cost, and ease of the technique in our video makes it accessible to any ophthalmologist. An investigation such as optical coherence tomography angiography (OCTA) to identify the afferent vessels, though more objective, may make the process cumbersome and expensive.
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Conflicts of interest
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References
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