Anterior segment parameters using Pentacam and prediction of corneal endothelial cell loss after cataract surgery.

PURPOSE: We evaluated various preoperative anterior segment parameters measured with a Pentacam rotating Scheimpflug camera and compared them with those of conventional methods. We also evaluated the effect of different parameters on corneal endothelial cells after cataract surgery. METHODS: Pentacam examination was performed in 88 eyes from 88 patients to evaluate central anterior chamber depth (ACD(pentacam)), nuclear density (Densitometry(pentacam)), anterior chamber volume (ACV), and lens thickness (LT(pentacam)). We compared values of ACD(pentacam) with those of ultrasound (ACD(sono)) and also compared Densitometry(pentacam) values with those of Lens Opacities Classification System (LOCS III) classification. We evaluated the effect of the following preoperative values measured with Pentacam on postoperative endothelial cell loss: pupil size measured both preoperatively and before capsulorrhexsis (Pupil(CCC)), amount of viscoelastics, and LT measured by ultrasound (LT(sono)). RESULTS: A SIGNIFICANT CONCORDANCE WAS FOUND BETWEEN THE TWO GRADING METHODS OF NUCLEAR OPACITY: Densitometry(pentacam) and LOCS III classification (τ(b) = 0.414, p = 0.000). We also found a positive correlation between ACD(pentacam) and ACD(sono) (r = 0.823, p = 0.000) and between ACD(pentacam) and ACV (r = 0.650, p = 0.000). There were significant differences between the results of LT(pentacam) and LT(sono). The final regression model identified Densitometry(pentacam), viscoelastics and Pupil(CCC) as independent predictors of decreased postoperative corneal endothelial cell density (CD) at postoperative day 3, and Densitometry(pentacam), viscoelastics, and ACV as independent predictors of decreased CD two months postoperatively (p<0.05). CONCLUSIONS: Good agreement was found between all results obtained with the Pentacam and conventional methods except LT. Analyzing anterior chamber parameters preoperatively using Pentacam could be helpful to predict postoperative endothelial cell loss.

Risk factors for endothelial cell loss after phacoemulsification: comparison in different anterior chamber depth groups.

PURPOSE: To assess the risk factors for endothelial cell loss after phacoemulsification with implantation of intraocular lens according to anterior chamber depth (ACD). METHODS: This prospective study included 94 eyes of 94 patients undergoing phacoemulsification cataract surgery. To assess the risk factors for corneal endothelial cell loss, we examined seven variables at 1 day, 1 week, 6 weeks, and 12 weeks postoperatively in each ACD-stratified group. RESULTS: Multiple linear regression analysis showed that the only variable influencing the percentage decrease in corneal endothelial cell density throughout the postoperative follow-up period in the long ACD group (ACD III) was nucleosclerosis. The variables influencing the percentage decrease in corneal endothelial cell density in the short ACD group (ACD I) at one day and one week postoperatively were corneal incisional tunnel length and nucleosclerosis. CONCLUSIONS: Risk factors for endothelial cell loss after phaoemulsification were different according to ACD. Long corneal tunnel length can be one of the risk factors for endothelial cell loss in short ACD eyes.

Dry eye after cataract surgery and associated intraoperative risk factors.

PURPOSE: To investigate changes in dry eye symptoms and diagnostic test values after cataract surgery and to address factors that might influence those symptoms and test results. METHODS: Twenty-eight eyes from 14 patients with preoperative dry eye (dry eye group) and 70 eyes from 35 patients without preoperative dry eye (non-dry eye group) were studied prospectively. In each group, we measured values such as tear break-up time (tBUT), Schirmer I test (ST-I), tear meniscus height (TMH), and subjective dry eye symptoms (Sx), and evaluated the postoperative changes in these values. We also evaluated the influence of corneal incision location and shape on these values. The correlations between these values and microscopic light exposure time and phacoemulsification energy were investigated. RESULTS: In the dry eye group, there were significant aggravations in Sx at 2 months postoperatively and in TMH at 3 days, 10 days, 1 month, and 2 months postoperatively, compared with preoperative values. All dry eye test values were significantly worse after cataract surgery in the non-dry eye group. With regard to incision location, there was no difference in tBUT, Sx, ST-I, or TMH in either the dry eye group or the non-dry eye group at any postoperative time point. Regarding incision shape, there was no difference in tBUT, Sx, ST-I or TMH at any postoperative time point in the dry eye group. In the superior incision sub-group of the non-dry eye group, tBUT and Sx were worse in the grooved incision group at day 1. In the temporal incision sub-group of the non-dry eye group, Sx were worse in the grooved incision group at 1 day, 3 days, and 10 days postoperatively. In both groups, significant correlations were noted between microscopic light exposure time and dry eye test values, but no correlation was noted between phacoemulsification energy and dry eye test values. CONCLUSIONS: Cataract surgery may lead to dry eye. A grooved incision can aggravate the symptoms during the early postoperative period in patients without dry eye preoperatively. Long microscopic light exposure times can have an adverse effect on dry eye test values.

Perioperative modulating factors on astigmatism in sutured cataract surgery.

PURPOSE: To evaluate the factors that affect postoperative astigmatism and post-suture removal astigmatism, and to evaluate the risk factors associated with astigmatism axis shift. METHODS: We performed a retrospective chart review of 130 eyes that had undergone uneventful phacoemulsification cataract surgery. Preoperative astigmatism was divided into four groups (Groups I, II, III, and IV) according to the differences between the axis of preoperative astigmatism (flattest axis) and the incision axis (105 degrees). We analyzed the magnitude and axis of the induced astigmatism after the operation and after suture removal in each group. We also analyzed the factors which affected the postoperative astigmatism and post-suture removal astigmatism in each sub-group of Groups I, II, III, and IV, excluding postoperative or post-suture removal axis shift (specifically, Group I(WAS), II(WAS), III(WAS), and IV(WAS)). We identified the variables associated with the prevalence of postoperative astigmatism axis shift and those associated with the prevalence of post-suture removal axis shift. RESULTS: An increase in the magnitude of postoperative astigmatism was associated with an increase in the preoperative magnitude of astigmatism in Groups I(WAS), II(WAS), and III(WAS) (p<0.05), and with an increase in the corneal tunnel length in Group I(WAS). A decrease in the magnitude of postoperative astigmatism was associated with an increase in the corneal tunnel length in Groups III(WAS) and IV(WAS) (p<0.05). An increase in the magnitude of post-suture removal astigmatism was associated with an increase in the magnitude of postoperative astigmatism in Groups I(WAS) and IV(WAS) (p<0.05), and with late suture removal in Group IV(WAS) (p<0.05). A decrease in the magnitude of post-suture removal astigmatism was associated with late suture removal in Groups I(WAS) and II(WAS). A logistic regression analysis showed that the prevalence of post-suture removal astigmatism axis shift was associated with increased corneal tunnel length, decreased magnitude of postoperative astigmatism, and early suture removal. CONCLUSIONS: In order to reduce postoperative and post-suture removal astigmatism, we recommend a short corneal tunnel length and late suture removal in patients with Group I(WAS) characteristics, late suture removal in Group II(WAS)-like patients, long corneal tunnel length in Group III(WAS)-like patients, and long corneal tunnel length and early suture removal in patients with characteristics of Group IV(WAS).

Early intraocular pressure and anterior chamber depth changes after phacoemulsification and intraocular lens implantation in nonglaucomatous eyes. Comparison of groups stratified by axial length.

PURPOSE: To evaluate the changes in intraocular pressure (IOP) and anterior chamber depth (ACD) after phacoemulsification according to axial length (AL). SETTING: Department of Ophthalmology, St. Vincent's Hospital, Catholic University of Korea, Suwon, South Korea. METHODS: This prospective study comprised 71 eyes of 71 patients who had phacoemulsification and foldable intraocular lens (IOL) implantation. The IOP changes preoperatively and 1 day and 1, 3, and 5 weeks postoperatively and ACD changes preoperatively and at 1 day and 3 and 5 weeks were analyzed by AL (AL1, 21.0 to <23.0 mm; AL2, 23.0 to <25.0 mm; AL3, 25.0 to <27.0 mm; AL4, >or=27.0 mm). RESULTS: There was no statistically significant difference in preoperative IOP according to AL. However, there was a statistically significant postoperative IOP decrease in the AL1 and AL2 groups and a statistically significant IOP increase in the AL3 and AL4 groups. There was a statistically significant difference in the preoperative ACD between AL groups and a statistically significant increase in ACD with increased AL from preoperatively to 1, 3, and 5 weeks postoperatively. CONCLUSIONS: After uneventful phacoemulsification and foldable IOL implantation, the IOP and ACD changed significantly according to AL in the early postoperative period. The AL appeared to predict these changes.