Analysis of Positional Relationships of Various Centers in Cataract Surgery

PURPOSE: To analyze the positional relationships of various centers in patients undergoing femtosecond laser-assisted cataract surgery (FLACS). METHODS: The locations of the pupil center (PC), limbal center (LC) and lens center were analyzed in each patient using optical coherence tomography during FLACS in 35 eyes of 35 patients. Using the preoperative corneal aberrometry device, angle kappa and the location of the visual axis (VA) were calculated. After acquiring the relative horizontal and vertical coordinates of each center, the distance and location among each center were compared. The relative location and distance of each center were statistically evaluated. RESULTS: The distance from the PC to the lens center was 0.147 ± 0.103 mm, that from the LC to the lens center was 0.205 ± 0.104 mm, and that from the VA to the lens center was 0.296 ± 0.198 mm. The distance from the PC to the VA was 0.283 ± 0.161 mm, that from the LC to the VA was 0.362 ± 0.153 mm, and that from the lens center to the VA was 0.296 ± 0.198 mm. Among the various centers, the PC was the closest to the lens center, whereas the LC and VA were the farthest. Based on the location of the lens center, the PC, LC, and VA exhibited differences in the X and Y coordinate positions (vertical p = 0.004, horizontal p < 0.001). Among them, the LC was significantly inferior and temporal compared to the PC (vertical p = 0.026, horizontal p = 0.023). Based on the location of the VA, the respective locations of the PC, LC and lens center in two dimensions did not significantly differ (vertical p = 0.310, horizontal p = 0.926). CONCLUSIONS: This study demonstrated the positional and locational relationships between the centers regarding FLACS. The locations of the PC, LC, and VA were different from the lens center with the PC being the closest. Surgeons should be aware of these positional relationships, especially in FLACS.

Effects of Choroidal Thickness on Refractive Outcome Following Cataract Surgery in Primary Angle Closure

PURPOSE: To identify the preoperative biometric factors, including subfoveal choroidal thickness (CT), associated with refractive outcome after cataract surgery in eyes with primary angle closure (PAC). METHODS: This study included 50 eyes of 50 PAC patients who underwent uneventful cataract surgery. Preoperatively, anterior segment parameters including anterior chamber depth (ACD) and lens vault were determined by anterior segment optical coherence tomography. Subfoveal CT was measured by spectral domain optical coherence tomography enhanced depth imaging before and at one month after surgery. Mean refractive error (MRE) was calculated as the difference in spherical equivalent between actual postoperative refraction determined one month postoperatively and that predicted using each of three IOL calculation formulas (SRK/II, SRK/T, and Haigis). Regression analyses were performed to investigate potential associations between MRE and putative factors. RESULTS: Mean ACD was 1.9 ± 0.4 mm, and preoperative subfoveal CT was 250.8 ± 56.9 µm. The SRK/T (MRE, 0.199 ± 0.567 diopters [D]) and Haigis (MRE, 0.190 ± 0.727 D) formulas showed slight hyperopic shift, while the SRK/II formula demonstrated a myopic shift (MRE, −0.077 ± 0.623 D) compared with that expected after cataract surgery. Mean absolute refractive error was not significantly different between formulas. Higher preoperative lens vault and shallower ACD were associated with a hyperopic shift in all formulas, but not in a statistically significant manner. Thicker preoperative subfoveal choroid was associated with a myopic shift after cataract surgery in all formulas (SRK/II: β = −0.511, p < 0.001; SRK/T: β = −0.652, p < 0.001; Haigis: β = −0.671, p < 0.001). Greater postoperative reduction of subfoveal CT was associated with a myopic shift after cataract surgery in all formulas (SRK/II: β = −0.511, p < 0.001; SRK/T: β = −0.652, p < 0.001; Haigis: β = −0.671, p < 0.001). CONCLUSIONS: Our results indicate that preoperative subfoveal CT and the difference between pre- and postoperative subfoveal CT are significant factors for predicting refractive error after cataract surgery in PAC patients. These findings should be considered when performing cataract surgery to optimize visual outcomes.

Clinical Analysis of Electroretinogram in Hypertensive Retinopathy

PURPOSE: Among electroretinogram variables, changes in OPs have frequently been reported as an early index of microcirculatory changes in diabetes mellitus patients without clinical signs of diabetic retinopathy. But studies on the relationship of hypertensive retinopathy and ERG have rarely been reported. This study was performed to investigate the relationship between retinal functional damage of hypertension and related changes in ERG. METHODS: Sixty-six essential hypertensive patients who visited our health screening center from January to July in 2001 were incruited as subjects. Among 122 eyes of 61 patients, 56 eyes with normal appearing retina were classified as group A while another 66 eyes with evidence of hypertensive retinopathy were as group B and 30 eyes of 15 persons of similar ages with normal blood pressure were normal control group as group C. Amplitude and implicit time were measured according to the standard electroretinogram procedure recommended by the ISCEV. RESULTS: In rod response, the amplitude of b wave of group A and B were smaller than that of group C(p<0.01), and the SOP of group A and B were also smaller than that of group C(p<0.01). The SOP of group B was smaller than that of group A(P<0.01). Regardless of degree of hypertension, the SOP value of group B was smaller than that of group A(P<0.01). Among patients with less than 5 years of duration, the SOP value of group B was smaller than that of group A(P<0.01). Among Group A with more than 5 years of duration, regardless of hypertensive retinopathy, the SOP was decreased. Among Group B with less than 5 years of duration, the SOP was also decreased regardless of retinopathy. CONCLUSIONS: Regardless of hypertensive retinopahy, scotopic b-amplitude and SOP were reduced in hypertension patients. Those patient with longer duration, decreased SOP was related to microcirculation alteration in hypertension despite normal appearing retina.

A Case of Fusarium solani Keratitis mixed by Acremonium falciforme

Although more reports on the fungal keratitis are recently coming out, cases of mixed infection by two or more fungal agents have not yet beenreported in the literature. The authors experienced a case of fungal keratitis caused by a combination of Fusarium solani and Acremonium falciforme in which central corneal ulcer with severe suppurative infilteration and hypopyon were observed. Since the conditions were resistant to conservative treatment and corneal perforation occurred despite of medical treatment, penetrating keratoplasty was performed along with postoperative topical and systemic antifungal therapies for several weeks and good results were obtained with no evidence of recurrence.

Results of Surgical Treatment of Complicated Pars Planitis

We performed pars plana vitrectomy on 19 patients with pars planitis with its complications like vitreous opacity and retinal detachment.There were 16 males and 3 females with a mean age of 42.8 years.The follow-up ranged from 6 to 122 months with a mean of 25 months.Following surgery, final visual acuity was improved or unchanged in the 78.9 percent of patients.Eight cases (42.1%)showed improved vision, seven patients (36.8%) showed no change and four cases (21.1%)worse vision.Retinal detachment was successfully repaired in 17 patients and two eyes failed anatomically due to the proliferative vitreoretinopathy.The main factor favoring functional success was the short duration from the onset to the time of vitrectomy.It might be concluded that vitrectomy should be performed in the vision threatening stages on the patients with complicated pars planitis.