Sir,

Internal limiting membrane (ILM) peeling is an important step, ensuring the surgical success of macular hole surgery.1 Various ILM peeling methods are available, one of which involves use of a diamond scraper.2 By rubbing the retinal surface with the abrasive edge of the scraper, selective ILM peeling is achieved. However, there is a risk of shedding of diamond particles from the scraper tip to the retina during peeling. Gupta et al3 reported iatrogenic deposits of diamond particles after pars plana vitrectomy (PPV) that included ILM peeling using a diamond scraper. The diamond particles had no effect on visual acuity or the visual field on short-term follow-up.

We performed a PPV with ILM peeling to treat a patient with full-thickness macular hole. A Tano Diamond-Dusted Membrane Scraper (Synergetics Inc., O'Fallon, MO, USA) was used to create an ILM edge before peeling. No complications were experienced during surgery. After 1 month, two highly reflective diamond particles were observed in the macular area. Best-corrected visual acuity (logMAR) was 0.1 and this was maintained until 1 year of follow-up. The diamond particles were still evident, but no morphological change of the macula was noted. Time domain (TD) optical coherence tomography (Stratus OCT, Carl Zeiss Meditec Inc., Dublin, CA, USA) did not detect the diamond particles, but spectral domain (SD) OCT (Spectralis OCT, Heidelberg Engineering, Carlsbad, CA, USA) revealed intraretinal particles, which were thus not on the retinal surface (Figure 1).

Figure 1
figure 1

A postoperative fundus photograph shows two glistening diamond particles on the macula. (a) SD OCT reveals two highly reflective intraretinal diamond particles. (b) TD OCT could not detect the particles (c).

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Thus, SD OCT could detect the highly reflective diamond particles, and their locations were confirmed by high-resolution imaging. TD OCT could not detect the particles because images were of low resolution. Diamond particles released during surgery should certainly be removed, but this may be difficult because of their small size. Although the particles remained within the retina, no effect on any of visual acuity, visual field, or retinal structure was evident up to 1 postoperative year. To the best of our knowledge, no SD OCT images of diamond particles or long-term follow-up data from a patient carrying such particles have been reported. In conclusion, SD OCT could detect small diamond particles in the retina, but no visual problem was noted at the 1-year follow-up.