Comparison of Legacy and New No-History IOL Power Calculation Formulas in Postmyopic Laser Vision Correction Eyes.

PURPOSE: To compare the refractive accuracy of legacy and new no-history formulas in eyes with previous myopic laser vision correction (M-LVC). DESIGN: Retrospective cohort study. METHODS: Setting: Two academic centers Study Population: 576 eyes (400 patients) with previous M-LVC that underwent cataract surgery between 2019-2023. A SS-OCT biometer was used to obtain biometric measurements, including standard (K), posterior (PK), and total keratometry values (TK). OBSERVATION PROCEDURES: Refractive prediction errors were calculated for 11 no-history formulas: two legacy M-LVC formulas, four new M-LVC formulas using K values only, and five new M-LVC formulas using K with PK or TK. MAIN OUTCOME MEASURES: Heteroscedastic testing was used to evaluate relative formula performance, and formulas were ranked by root mean square error (RMSE). RESULTS: New M-LVC formulas performed better than legacy M-LVC formulas. New M-LVC formulas with PK/TK values performed better than versions without PK/TK values. Among new M-LVC formulas with PK/TK values, EVO 2.0-PK was superior to Hoffer QST-PK (P < 0.005). Among new M-LVC formulas using K only, Pearl DGS-K and EVO 2.0-K were both superior to Hoffer QST-K and Barrett True K NH-K formulas (all P < 0.005). CONCLUSIONS: Surgeons should favor using new no-history post M-LVC formulas over legacy post M-LVC formulas whenever possible. The top-performing M-LVC formulas (EVO 2.0-PK, Pearl DGS-PK, and Barrett True K-TK) utilized posterior corneal power values. Among formulas utilizing K alone, the EVO 2.0-K and Pearl DGS-K performed best.

Intraocular Lens Power Calculations in Keratoconus Eyes Comparing Keratometry, Total Keratometry, and Newer Formulae.

PURPOSE: To compare the utility of keratometry vs total keratometry (TK) for intraocular lens power calculations in eyes with keratoconus (KCN) using KCN and non-KCN formulae. DESIGN: Retrospective cohort study. METHODS: This study was conducted at 2 academic centers and included 87 eyes in 67 patients who underwent cataract surgery between 2019 and 2021. Biometry measurements were obtained using a swept-source optical coherence tomography biometer (IOL Master 700). Refractive prediction errors, including root mean square error (RMSE), were calculated for 13 formulae. These included 4 classical formulae (Haigis, Hoffer Q, Holladay 1 [H1], and SRK/T), 5 new formulae (NF) (Barrett Universal II [BU2], Cooke K6, EVO 2.0, Kane, and Pearl-DGS), 3 KCN formulae (BU2 KCN: M-PCA, BU2 KCN: P-PCA, and Kane KCN), and H1 with equivalent keratometry reading values (H1-EKR). Formulae were ranked by RMSE. Friedman analysis of variance with post hoc analysis and H-testing was used for statistical significance testing. RESULTS: KCN formulae had the lowest RMSEs in all eyes, and BU2 KCN:M-PCA performed the best among KCN formulae in all subgroups. In eyes with severe KCN, if TK values are unavailable, the BU2 KCN: P-PCA performed better than the top-ranked non-KCN formula (SRK/T). In eyes with nonsevere KCN, if TK values are unavailable, EVO 2.0 K was statistically superior to the next competitor (Kane K). H1-EKR had the highest RMSE. CONCLUSIONS: KCN formulae and TK are useful for intraocular lens power calculations in KCN eyes, especially in eyes with severe KCN. The BU2 KCN: M-PCA using TK values performed best for eyes with all severities of KCN. For eyes with nonsevere KCN, the EVO 2.0 TK or K can also be used.

Outcomes of Nontuberculous Mycobacterial Keratitis After Clear Corneal Incision Phacoemulsification Surgery: A Case Series of 6 Eyes in South Florida.

PURPOSE: The purpose of this study was to present the successful management and outcomes in a series of 6 cases of culture-positive nontuberculous mycobacterial keratitis after clear corneal incision phacoemulsification surgery. METHODS: This is a case series of 6 consecutive eyes that presented at the Cornea Division at an academic institution, diagnosed with culture-positive nontuberculous mycobacterial keratitis after phacoemulsification surgery. RESULTS: Six eyes of 5 patients were included. The mean interval from cataract surgery to presentation was 7.7 weeks. All cases presented with intrastromal abscesses adjacent to corneal incisions, and 2 had scleral extension of the infection. Isolated organisms were Mycobacterium abscessus (n = 4), Mycobacterium chelonae (n = 1), and Mycobacterium mucogenicum (n = 1). All cases were treated with topical amikacin 8 mg/mL for 10.5 weeks on average. All cases received either oral clarithromycin at 500 mg twice-daily dosage or oral azithromycin at 500 mg daily. Two patients with scleral abscesses underwent surgical debridement with amniotic membrane grafts. All 6 eyes achieved infection resolution and good visual recovery, with the final visual acuity ranging from 20/20 to 20/60. None of the patients experienced recurrence of infection. CONCLUSIONS: Prompt medical treatment with combined topical and oral therapy can lead to infection resolution and favorable visual recovery. Early surgical intervention can ensure good outcomes in cases of scleral extension.

Manual Provocation Test for Intermittent Involutional Entropion.

PURPOSE: To describe the manual provocation test (MPT), a novel test for intermittent involutional entropion of the lower eyelid. METHODS: Retrospective review of patients with intermittent entropion who presented with ocular irritation and documented inward eyelid rotation by them or their referring physicians, but who had no apparent entropion at the time of initial consultation. Results of the MPT were recorded for this group, and then evaluated prospectively in an age-matched comparison group of patients presenting for blepharoplasty who had no history of entropion. The essential steps of the MPT are as follows. Step 1: the lower eyelid skin is grasped below the inferior border of the tarsal plate. Step 2: the lid is drawn anteriorly as with the eyelid distraction test. Step 3: the patient is directed to forcefully close the eyelids. Step 4: the eyelid is released and the result is observed for manifest entropion. RESULTS: Thirteen eyelids in 12 patients with intermittent involutional lower eyelid entropion were included in this study. Average patient age was 77.3 years (±9.5 SD). The MPT elicited entropion in all 13 eyelids. Of the 12 patients, 9 elected to pursue surgery and, of these patients, all eyelids were successfully treated with subsequent improvement of symptoms. The MPT was thereafter negative in these patients. None of the 20 patients in the blepharoplasty comparison group (average age 71.6 years) demonstrated a positive MPT. CONCLUSIONS: The MPT can be a valuable and straightforward test in the clinical evaluation of patients with a history of intermittent entropion.