Purpose: To seek Pearson correlations of tear film osmolarity measured by the I-PEN® (I-MED Pharma Inc., Dollard-des-Ormeaux, Canada) with Schirmer test result, tear break-up time, and Ocular Surface Disease Index score in patients with mild dry eye syndrome. Methods: Patients with mild dry eye syndrome were divided into two groups according to Ocular Staining Score: group 1 (50 patients; 67 eyes) and group 2 (59 patients; 91 eyes), 90 patients and 158 eyes in total. The above mentioned correlations were derived. Results: No significant correlations were observed between tear film osmolarity and Schirmer test result (r < -0.01, p = 0.97), tear break-up time (r = 0.05, p = 0.54), or Ocular Surface Disease Index score (r = 0.03, p = 0.76). When the two groups were compared, the Ocular Surface Disease Index score significantly differed between groups (p < 0.01), whereas the Schirmer test result (p = 0.31), tear break-up time (p = 0.11), and tear film osmolarity (p = 0.12) did not. Conclusions No significant correlations were found between tear film osmolarity and other dry eye indicators in patients with mild dry eye syndrome. The diagnostic utility of tear film osmolarity in patients with moderate dry eye syndrome is should be evaluated.

Purpose: To seek Pearson correlations of tear film osmolarity measured by the I-PEN® (I-MED Pharma Inc., Dollard-des-Ormeaux, Canada) with Schirmer test result, tear break-up time, and Ocular Surface Disease Index score in patients with mild dry eye syndrome. Methods: Patients with mild dry eye syndrome were divided into two groups according to Ocular Staining Score: group 1 (50 patients; 67 eyes) and group 2 (59 patients; 91 eyes), 90 patients and 158 eyes in total. The above mentioned correlations were derived. Results: No significant correlations were observed between tear film osmolarity and Schirmer test result (r < -0.01, p = 0.97), tear break-up time (r = 0.05, p = 0.54), or Ocular Surface Disease Index score (r = 0.03, p = 0.76). When the two groups were compared, the Ocular Surface Disease Index score significantly differed between groups (p < 0.01), whereas the Schirmer test result (p = 0.31), tear break-up time (p = 0.11), and tear film osmolarity (p = 0.12) did not. Conclusions No significant correlations were found between tear film osmolarity and other dry eye indicators in patients with mild dry eye syndrome. The diagnostic utility of tear film osmolarity in patients with moderate dry eye syndrome is should be evaluated.

Purpose: To calculate the intraocular lens (IOL) power using the Shammas-PL formula after laser in-situ keratomileusis (LASIK). Methods: Forty-one eyes of 29 patients that had undergone cataract surgery from September 2018 to September 2019 after LASIK were enrolled in this study. A preoperative AL-Scan® (Nidek Co., Gamagori, Japan) was used to measure the axial length, anterior chamber depth, and corneal curvature. An IOL power calculation was performed using the Shammas-PL (post LASIK) formula. Mean absolute error (MAE) and mean arithmetic error (MARE) were calculated using preoperative manifest refraction and postoperative manifest refraction. Results: Of the 41 eyes, 15 eyes (36.6%) were relatively hyperopic-shifted after surgery compared to the predicted refractive error before surgery, 25 eyes (61%) showed a relative myopic shift, and one eye (2.4%) showed no change with respect to the previous refractive predicted error. Refractive errors before cataract surgery were not related to myopic, emmetropic, or hyperopic shifting after surgery (p > 0.05). Conclusions When cataract surgery using the Shammas-PL formula was performed after LASIK, myopic shifting was more common than hyperopic shifting. The MAE was greater in myopic-shifted cases than that of hyperopic-shifted cases. Thus, it is better to determine IOL power toward the hyperopic side than the target refractive prediction.

Purpose: To compare the accuracy of standard and total keratometry data obtained using the Barrett Universal II and Barrett Toric Calculator. Methods: In total, 111 eyes of 111 patients who visited our hospital for cataract surgery from February 2019 to September 2019 were included in this study. Total keratometry and standard keratometry data were obtained using the Barrett Universal II and the Barrett Toric Calculator; mean absolute errors were derived by using preoperative IOL Master 700® (Carl Zeiss Meditech AG, Jena, Germany) data and 2-month postoperative manifest refraction data. The mean absolute errors of the two methods were compared in terms of a posterior corneal astigmatism greater than 0.3 diopter (D) in patients fitted with Toric intraocular lenses. Results: Using the Barrett Universal II formula, the mean absolute error spherical equivalent difference between total keratometry and standard keratometry was 0.021 ± 0.102 D (p = 0.65) when the Barrett Toric Calculator was used. The mean absolute error differences between the two methods were 0.015 ± 0.121 D for the spherical equivalent (p = 0.80) and 0.005 ± 0.870 D for the cylinder measurement (p = 0.94). In terms of a posterior corneal astigmatism greater than 0.3 D, the mean absolute error spherical equivalent and cylinder measurement differences were -0.020 ± 0.107 D (p = 0.70) and -0.023 ± 0.055 D (p = 0.50) in patients fitted with Toric intraocular lenses. Conclusions The total keratometry method, which directly measures posterior corneal curvature, yields data comparable to those of the standard keratometry method. When the posterior corneal astigmatism was greater than 0.3 D, we found no significant difference between the total keratometry and standard keratometry data of patients fitted with Toric intraocular lenses.

Purpose: The Eyelike K-flex Aspheric® (Koryoeyetech, Seoul, Korea) is manufactured in 0.25-diopter (D) intervals, which allows the target refractive error after surgery to be achieved. We here evaluate the refractive power outcomes. Methods: We retrospectively studied 95 eyes of 72 patients who underwent cataract surgery with implantation of the Eyelike K-flex Aspheric®. Refractive error was measured at 1 and 2 months postoperatively (33 eyes of 27 patients) and compared to that of patients fitted with 0.50-D-interval lenses (62 eyes of 49 patients). Results: At 1 month postoperatively, the mean absolute error between the spherical equivalent and planned value was 0.33 ± 0.28 and 0.41 ± 0.39 D in the 0.25- and 0.50 D-interval lens groups, respectively (p = 0.318). At 2 months postoperatively, the respective values were 0.21 ± 0.15 and 0.34 ± 0.29 D (p = 0.009). Conclusions The Eyelike K-flex Aspheric® shows excellent refractive predictability; use of 0.25-D-interval intraocular lenses close to the target refractive power allows the desired spherical equivalent to be achieved.

Purpose: To compare the accuracy of standard and total keratometry data obtained using the Barrett Universal II and Barrett Toric Calculator. Methods: In total, 111 eyes of 111 patients who visited our hospital for cataract surgery from February 2019 to September 2019 were included in this study. Total keratometry and standard keratometry data were obtained using the Barrett Universal II and the Barrett Toric Calculator; mean absolute errors were derived by using preoperative IOL Master 700® (Carl Zeiss Meditech AG, Jena, Germany) data and 2-month postoperative manifest refraction data. The mean absolute errors of the two methods were compared in terms of a posterior corneal astigmatism greater than 0.3 diopter (D) in patients fitted with Toric intraocular lenses. Results: Using the Barrett Universal II formula, the mean absolute error spherical equivalent difference between total keratometry and standard keratometry was 0.021 ± 0.102 D (p = 0.65) when the Barrett Toric Calculator was used. The mean absolute error differences between the two methods were 0.015 ± 0.121 D for the spherical equivalent (p = 0.80) and 0.005 ± 0.870 D for the cylinder measurement (p = 0.94). In terms of a posterior corneal astigmatism greater than 0.3 D, the mean absolute error spherical equivalent and cylinder measurement differences were -0.020 ± 0.107 D (p = 0.70) and -0.023 ± 0.055 D (p = 0.50) in patients fitted with Toric intraocular lenses. Conclusions The total keratometry method, which directly measures posterior corneal curvature, yields data comparable to those of the standard keratometry method. When the posterior corneal astigmatism was greater than 0.3 D, we found no significant difference between the total keratometry and standard keratometry data of patients fitted with Toric intraocular lenses.

Purpose: The Eyelike K-flex Aspheric® (Koryoeyetech, Seoul, Korea) is manufactured in 0.25-diopter (D) intervals, which allows the target refractive error after surgery to be achieved. We here evaluate the refractive power outcomes. Methods: We retrospectively studied 95 eyes of 72 patients who underwent cataract surgery with implantation of the Eyelike K-flex Aspheric®. Refractive error was measured at 1 and 2 months postoperatively (33 eyes of 27 patients) and compared to that of patients fitted with 0.50-D-interval lenses (62 eyes of 49 patients). Results: At 1 month postoperatively, the mean absolute error between the spherical equivalent and planned value was 0.33 ± 0.28 and 0.41 ± 0.39 D in the 0.25- and 0.50 D-interval lens groups, respectively (p = 0.318). At 2 months postoperatively, the respective values were 0.21 ± 0.15 and 0.34 ± 0.29 D (p = 0.009). Conclusions The Eyelike K-flex Aspheric® shows excellent refractive predictability; use of 0.25-D-interval intraocular lenses close to the target refractive power allows the desired spherical equivalent to be achieved.

Purpose: To compare contrast sensitivity before and after surgery in patients who underwent laser in situ keratomileusis (LASIK)and small-incision lenticule extraction (SMILE). Methods: From February 2019 to April 2019, 20 patients who underwent LASIK, and 21 who underwent SMILE, were comparedbefore, one day, one week, and one month after surgery. Results: On postoperative day (POD) 1, contrast sensitivity was better in the LASIK group than in the SMILE group under all conditionsfor 1.6, 1, and 0.64 cycles per degree (cpd). One week after surgery, the contrast sensitivity of the LASIK group was betterthan that of the SMILE group under photopic conditions with glare for 1.6, 1, and 0.64 cpd, under photopic conditions withoutglare for 1 and 0.64 cpd, and under all scotopic conditions for 2.5, 1.6, and 0.64 cpd (p< 0.05). There was no significant differencebetween the two groups, except under the scotopic conditions without glare for 0.64 cpd at one month after surgery. In theLASIK group, the contrast sensitivity was best at one week after surgery. The SMILE group showed the poorest contrast sensitivityon POD 1, but this gradually improved. Conclusions The LASIK group had better contrast sensitivity on one day and one week after surgery than the SMILE group, butthere was no significant difference at one month after surgery. In the LASIK group, the contrast sensitivity was best at one weekafter surgery. In the SMILE group, the contrast sensitivity was worst on POD 1.

Purpose: To report a case of central toxic keratopathy after femtosecond laser in-situ keratomileusis (LASIK).Case summary: A 26-year-old male developed diffuse lamellar keratitis bilaterally on day 2 after femtosecond LASIK. He was applying topical steroid frequently, while also using topical antibiotics. On day 6 after LASIK, slit-lamp biomicroscopy showed a thick central corneal opacity on the right eye so a flap irrigation was performed. He was then treated with systemic methylprednisolone. A corneal epithelial crack and stromal striae were noted by slit-lamp biomicroscopy on postoperative day 10. Four weeks after LASIK, the refractive error was +4.25 Dsph = -1.25 Dcyl Axis 80°. He was treated with topical steroid, topical antibiotics, and oral doxycycline until eight weeks after LASIK. Eight weeks after LASIK, the patient was observed without treatment. The central corneal thickness recovered from 488 μm at eight weeks to 540 μm, and the refractive error was +1.25 Dsph = -0.75 Dcyl Axis 85° at postoperative 72 weeks. The central corneal opacity also recovered. Conclusions Because femtosecond LASIK may result in a combination of diffuse lamellar keratitis and central toxic keratopathy, the clinical characteristics and natural course of both diseases should be understood and timely treatment should be available.

PURPOSE: To report a case of corneal and lenticular pigmentation after prolonged clozapine therapy. CASE SUMMARY: A 56-year-old male visited our hospital with a progressive decline in vision that affected both eyes. He had a history of schizophrenia. He was being treated with 200 mg clozapine and 1 mg lorazepam daily, and had been treated with clozapine for 5 years. At the first visit, his best-corrected-visual acuity was 20/32 in both eyes. Slit lamp examination of the corneas showed bright, fine, grayish-brown deposits on the endothelium, and on dilation, bilateral central stellate opacity of the anterior portion of the lens capsule was revealed. CONCLUSIONS: Clozapine may induce corneal and lenticular pigmentation and thus may lead to a decline in vision. Patients on long-term clozapine therapy should be considered for regular ophthalmic review.
Clozapine ; Cornea ; Endothelium ; Humans ; Lorazepam ; Male ; Middle Aged ; Pigmentation ; Schizophrenia ; Slit Lamp