Mr Brendon W. H. Lee1,2, Dr Jeremy Tan2, Dr Fiona Lau2,3, Dr Michelle Hui4, Dr Jenny Norman1,6, Dr Christopher Douglas7, Dr Ashish Agar1,2, Professor Minas Coroneo1,2, Associate Professor Ian Francis1,2,5
1Faculty of Medicine, University Of New South Wales, Sydney, Australia,
2Department of Ophthalmology, Prince of Wales Hospital, Sydney, Australia,
3St George and Sutherland Clinical School, Sydney, Australia,
4Royal Prince Alfred Hospital, Sydney, Australia,
5Chatswood Private Hospital, Sydney, Australia,
6Electron Microscope Unit, University of New South Wales, Sydney, Australia,
7Histopath Specialist Pathologists, Sydney, Australia
Purpose: To evaluate the incidence and significance of Deposition of Ophthalmic Viscoelastic Device in the Corneal Subepithelium (DOCS) at the sideport region following phacoemulsification cataract surgery (phaco).
Methods: Prospective, consecutive case series of 212 eyes that underwent phaco by a single ophthalmic surgeon. The presence and number of small transparent globules seen on slit lamp, presumed to be Ophthalmic Viscoelastic Device (OVD) deposition in the sideport region of the corneal subepithelium, was recorded at one day, one week, and one month postoperatively. A sample of loose epithelium containing the globules, near the sideport region, was removed and examined using microscopy (light, confocal, electron) and mass spectrometry. Other parameters measured included: age, gender, cataract nuclear sclerosis grade, intraoperative and postoperative complications, duration of surgery, and preoperative and postoperative corrected distance visual acuity (CDVA) at one day, one week, and one month. All patients received followup for at least one month postoperatively. The data were analysed using SPSS (version 21) statistical software.
Results: Confocal and light microscopy confirmed the transparent globular material in the corneal subepithelium to be OVD. DOCS was present at or near the sideport incision site, with significantly more DOCS observed at one week (27.5%) and one month (15.2%) after surgery than at day one (6.2%) postoperatively (p<0.001). There was a positive correlation between DOCS and duration of surgery (r=0.148, p=0.032). At one month postoperatively, 96.2% of the cohort achieved CDVA of at least 6/6.
Conclusion: The ophthalmological literature has not previously recorded DOCS. This study documents the incidence, slit lamp examination, confocal and light microscopic appearance, of DOCS at the sideport region following phaco. Furthermore, at one month followup, 15.2% of cases had residual DOCS at the sideport region. There appeared to be no detrimental effects either on surgical or visual outcomes in these patients. Thus, DOCS may represent a benign entity, whose diagnosis may be recognised by its unique appearance. The presence of DOCS should indicate to a clinician new to the patient that cataract surgery has been performed using OVD, and that the prognosis has likely not been adversely affected.
Brendon Lee is a fifth-year medical student at the University of New South Wales currently undertaking research with Prof Coroneo and A/Prof Francis. He has previously presented work at RANZCO and ARVO. He wishes to continue broadening his knowledge of ophthalmology by taking an elective later this year.