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Successful Müller muscle-conjunctiva resection in patients with Boston keratoprosthesis type I
Janet M Lim1, Genie M Bang, Maria S Cortina
1Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL.
Purpose:
To present a case series of patients with Boston keratoprosthesis type I (KPro) who have had successful ptosis repair with Müller muscle-conjunctiva resection (MMCR).
Methods:
Patients with KPros managed with MMCR for ptosis were identified. Records were examined to obtain preoperative and postoperative visual acuity, KPro viability, and eyelid measurements including margin-to-reflex distance 1 (MRD1), levator function, and lagophthalmos.
Results:
Seven eyes of 6 patients with KPros and ptosis treated with MMCR were identified. Four eyes underwent a lower lid tarsal strip procedure concurrently with the MMCR to minimize the risk of exposure to the graft postoperatively. The average time between KPro surgery and ptosis surgery was 29.1 months (range, 4-79 months). Preoperatively, the average MRD1 was -2.4 mm and the average levator function was 11.3 mm. Postoperatively, all eyelids were elevated and the average MRD1 was 0.9 mm. One eye had 0.5 mm of lagophthalmos noted whereas all other eyes had no lagophthalmos. The average follow-up time was 25.9 months (range, 13-41 months). All 7 eyes maintained a viable KPro without any compromise to the conjunctiva or donor corneal tissue.
Conclusions:
This retrospective case series describes 7 eyes with KPros that underwent successful MMCR without compromise to the integrity of the KPro. Because these patients are at high risk for potential complications, we recommend careful patient selection, a goal of undercorrection, and consideration of supplemental procedures to the lower eyelids to minimize complications to the KPro.
Insights
Müller muscle-conjunctiva resection (MMCR) successfully repaired ptosis in patients with Boston keratoprosthesis type I (KPro). This procedure maintained KPro viability and improved eyelid function without compromising the graft.
Area of Science:
- Ophthalmology
- Corneal Surgery
- Oculoplastics
Background:
- Boston keratoprosthesis type I (KPro) is a treatment for corneal blindness.
- Ptosis, or drooping eyelid, can obscure vision and complicate KPro outcomes.
- Müller muscle-conjunctiva resection (MMCR) is a surgical technique for ptosis repair.
Purpose of the Study:
- To evaluate the efficacy and safety of MMCR for ptosis repair in patients with KPro.
- To assess the impact of MMCR on KPro viability and visual outcomes.
Main Methods:
- A retrospective case series identified patients with KPro and ptosis treated with MMCR.
- Preoperative and postoperative data were collected, including visual acuity, KPro status, and eyelid measurements (MRD1, levator function, lagophthalmos).
- Concurrent lower lid procedures were performed in some cases to mitigate exposure risk.
Main Results:
- Seven eyes of 6 patients with KPro and ptosis underwent MMCR.
- Postoperative MRD1 improved from an average of -2.4 mm to 0.9 mm, indicating successful eyelid elevation.
- All KPros remained viable, with no compromise to conjunctival or corneal tissue observed during an average follow-up of 25.9 months.
Conclusions:
- MMCR is a safe and effective procedure for ptosis repair in KPro patients.
- Careful patient selection and consideration of supplemental lower lid procedures are recommended to minimize KPro-related complications.
- Successful MMCR can improve visual function without jeopardizing the KPro graft.
