Isolated traumatic aniridia with full and partial iris expulsion in pseudophakic eyes

BACKGROUND: Total aniridia after ocular trauma without disruption of the intraocular lens (IOL) has been reported in patients with a history of small-incisional cataract surgery. We report one case each of total and partial aniridia after accidental falls experienced by two elderly Japanese women. CASE PRESENTATIONS: Case 1. A 76-year-old woman with a history of small-incisional cataract surgery more than 10 years previously fell onto concrete and had a contusion that affected the left side of her face. At the initial visit, the best-corrected visual acuity (BCVA) was hand motions and the intraocular pressure (IOP) was 38 mmHg in her left eye (OS). A blood clot was present in the well-formed anterior chamber and expulsed iris tissue was seen beneath the conjunctiva. Exploratory surgery showed no scleral laceration other than the previous sclerocorneal tunnel. After hyphema removal, total aniridia and an intact in-the-bag fixed IOL were seen. By 4 months, the BCVA was 1.2 and the IOP was 13 mmHg OS. Case 2. An 88-year-old woman with a history of small-incisional cataract surgery more than 10 years previously had a fall that resulted in right-sided zygomatic and maxillary bone fractures. The BCVA was light perception and the IOP was 29 mmHg in her right eye (OD). Exploratory surgery showed no scleral laceration and the previous sclerocorneal tunnel was found; iris strand prolapsing from the sclerocorneal tunnel was seen. After hyphema removal, partial iris loss and an intact lens position were seen. By 1 week postoperatively, the BCVA was 0.05 OD and the IOP was 12 mmHg OD. CONCLUSIONS: It has been postulated that previously created small-incision tunnels can function as release valves during blunt trauma by preventing further global rupture and limiting IOL prolapse or retinal injury. Our cases suggested this can happen even long periods after cataract surgery. The case with partial aniridia demonstrated the process of the expulsive aniridia, and its findings do not contradict the postulated mechanisms. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12886-022-02615-4.