Ring-shaped dysphotopsia associated with posterior chamber phakic implantable collamer lenses with a central hole

Youngsub Eom, Dae Wook Kim, Dongok Ryu, Jun Heon Kim, Seul Ki Yang, Jong Suk Song, Sug Whan Kim, Hyo Myung Kim

Research output: Contribution to journalArticlepeer-review

38 Scopus citations


Purpose: To evaluate the incidence of central hole-induced ring-shaped dysphotopsia after posterior chamber phakic implantable collamer lens (ICL) with central hole (hole ICL) implantation and to investigate the causes of central hole-induced dysphotopsia. Methods: The clinical study enrolled 29 eyes of 15 consecutive myopic patients implanted with hole ICL. The incidence of ring-shaped dysphotopsia after hole ICL implantation was evaluated. In the experimental simulation study, non-sequential ray tracing was used to construct myopic human eye models with hole ICL and ICL without a central hole (conventional ICL). Simulated retinal images measured in log-scale irradiance were compared between the two ICLs for an extended Lambertian light-emitting disc object 20 cm in diameter placed 2 m from the corneal vertex. To investigate the causes of hole-induced dysphotopsia, a series of retinal images were simulated using point sources at infinity with well-defined field angles (0 to −20°) and multiple ICL models. Results: Of 29 eyes, 15 experienced ring-shaped dysphotopsia after hole ICL implantation. The simulation study using an extended Lambertian source showed that hole ICL-evoked ring-shaped dysphotopsia was formed at a retinal field angle of ±40°. Component-level analysis using a well-defined off-axis point source from infinity revealed that ring-shaped dysphotopsia was generated by stray light refraction from the inner wall of the hole and the posterior ICL surface. Conclusion: Hole ICL-evoked ring-shaped dysphotopsia was related to light refraction at the central hole structure. Surgeons are advised to explain to patients the possibility of ring-shaped dysphotopsia after hole ICL implantation.

Original languageEnglish (US)
Pages (from-to)e170-e178
JournalActa Ophthalmologica
Issue number3
StatePublished - May 1 2017


  • central hole
  • dysphotopsia
  • posterior chamber phakic implantable collamer lenses

ASJC Scopus subject areas

  • Ophthalmology

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