Uday Devgan, MD , 2025-05-21 14:57:00
A century ago, Theodor Axenfeld described a series of patients with congenital abnormalities of the anterior segment of the eye, including anterior displacement of Schwalbe’s line, termed posterior embryotoxon, with anterior iris adhesions.
Shortly thereafter, Herwigh Rieger noted more iris abnormalities such as corectopia, polycoria and iris atrophy in these patients along with systemic deformities of teeth and facial bones.
Figure 1. The anterior segment shows an irregularly shaped cornea with more of a rhomboid shape as well as the presence of posterior embryotoxon. There is corectopia with the pupil displaced because the temporal iris atrophy prevents symmetric dilation.
Source: Uday Devgan, MD
Due to the dysgenesis of the anterior segment, the eye is prone to more pathology such as development of glaucoma due to irregular angle anatomy. Fortunately, Axenfeld-Rieger syndrome is rare, and the degree of structural abnormalities can vary along a spectrum from mild to severe.
A patient was referred to our clinic for cataract surgery, and a considerable amount of time was spent evaluating the eye, with care taken to detect the presence of confounding factors that could complicate the procedure. The patient was noted to have an unusual corneal shape that appeared somewhat rhomboid (Figure 1). The posterior embryotoxon was visible in certain areas of the cornea, and notably there was corectopia with decentration of the pupil upon dilation due to an area of iris atrophy. No glaucoma was present, and the angle anatomy looked reasonable with only a few areas noted to have iris strands adherent to Schwalbe’s line.
Uday Devgan, MD
In cases of Axenfeld-Rieger syndrome, it is common to have zonular laxity with focal areas of zonular absence, particularly in the area of iris atrophy. While our patient seemed to have a normal degree of zonular support, this is better assessed during surgery. For this reason, we arranged to have additional instrumentation available in the operating room, such as capsule hooks, a capsular tension ring, a capsular tension segment and the appropriate sutures. This patient was also highly myopic with a long axial length and desired to maintain a moderate degree of myopia to allow for unaided near vision. IOL calculations were performed for the patient’s preferred refractive target, and a toric monofocal IOL was chosen as the first choice. We also arranged to have a three-piece monofocal IOL, which only comes in non-toric versions, available as a back-up plan.
Source: Uday Devgan, MD
In the operating room, we started with topical tetracaine and intracameral preservative-free lidocaine for anesthesia, along with some mild systemic sedation with midazolam. If the case became more complicated, we could always supplement that with a sub-Tenon’s administration of additional local anesthetics to achieve analgesia and akinesia. The incision was made temporally because that was the area of the cornea that was farthest from the visual axis. A superior incision in this case would be closer to the visual axis, and that would likely induce more astigmatic effect.
The initial creation of the capsulorrhexis gives important clues as to zonular laxity if we start it by puncturing the lens capsule with our forceps. If we use a sharp needle or cystotome instead, there is little feedback as to how taut the anterior capsule is. Fortunately, the zonular support seemed normal, and we could proceed with the capsulorrhexis. Importantly, the capsulorrhexis was centered on the capsule and not within the pupil. Because of the asymmetric pupil dilation, we wanted to avoid using the pupil margin as a guide for the capsulorrhexis because it would result in a misaligned anterior lens opening. (Figure 2)
Source: Uday Devgan, MD
The nucleus removal went smoothly in this case, using a phaco chop variation. During cortical cleanup, care was taken to observe the capsulorrhexis to ensure that it did not move. For a full 360°, the zonular support was strong, so a capsular tension ring was not needed. We implanted a toric monofocal IOL that was aligned at the appropriate axis to address the corneal astigmatism. Because of the care taken to create the capsulorrhexis, there was a complete 360° overlap of the IOL optic, which was well centered in the patient’s visual axis (Figure 3).
The patient achieved an excellent postoperative outcome and healed well from the surgery. She is being referred back to retina and glaucoma colleagues who will follow her longitudinally. For this patient, fortunately the degree of ocular abnormalities from Axenfeld-Rieger syndrome was limited, and the cataract surgery was uneventful for both eyes. Because this is a rare condition, occurring in less than one in 100,000 people, I may not see another patient with this condition in the second half of my career.
A video of this can be found at https://cataractcoach.com/category/unusual-cases/.
For more information:
Uday Devgan, MD, in private practice at Devgan Eye Surgery and a partner at Specialty Surgical Center in Beverly Hills, California, can be reached at devgan@gmail.com; website: www.CataractCoach.com.
Sources/Disclosures
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Disclosures:
Devgan reports owning and running CataractCoach.com, which is a free resource for ophthalmologists, and being a principal in RetinaRounds.com, which is also a free resource.
