• Journal of Yeungnam Medical Science
• /
• v.24 no.2
• /
• pp.243-251
• /
• 2007

Purpose : This study was conducted to assess the surgical outcomes of limbal lensectomy with or without anterior vitrectomy for the management of lens subluxation. Materials and Methods : The medical records of 20 consecutive patients (33 eyes) with lens subluxation who had undergone limbal lensectomy with or without anterior vitrectomy from February 1999 to January 2004 were retrospectively reviewed. Results : All the patients, except one high axial myopic patient, were implanted with scleral sutured posterior chamber intraocular lens. We evaluated the preoperative, postoperative visual acuity and postoperative complications and compared the results in group I (limbal lensectomy with anterior vitrectomy, 27 eyes) to those in group II (limbal lensectomy without anterior vitrectomy, 6 eyes). The preoperative best-corrected visual acuity was 0.21 and postoperative best-corrected visual acuity was improved by 2 lines or more in all 27 eyes in group I, and in 5 eyes in group II (p>0.05). The most frequent postoperative complication was intraocular lens dislocation in four eyes (14.8%) in group I alone. No retinal detachment occurred in either group, even in patients with high myopia. Conclusion : Limbal lensectomy without anterior vitrectomy improved visual acuity similarly to limbal lensectomy with anterior vitrectomy without significant increase of postoperative complications. This results of this study suggest that anterior vitrectomy is not necessarily required for the management of lens subluxation.

• Journal of The Korean Ophthalmological Society
• /
• v.59 no.12
• /
• pp.1137-1141
• /
• 2018

Purpose: We explored the mydriatic effects of injected intracameral epinephrine after phacoemulsification (PE) combined with phacovitrectomy to treat proliferative diabetic retinopathy (PDR). Methods: We enrolled 96 patients (96 eyes) who underwent phacovitrectomy to treat PDR; we used ImageJ software to measure pupil sizes and the ratios of pupil to cornea area (PCA) before and after PE and after pars plana vitrectomy (PPV). We compared pupil sizes between those who received intracameral epinephrine (0.001% w/v) after PE but before PPV (study group, 46 eyes) and patients not so treated (control group, 50 eyes). Results: The PCA ratios of the study group were $0.52{\pm}0.11$ before PE, $0.43{\pm}0.12$ after PE, and $0.51{\pm}0.11$ after PPV, respectively. Changes in pupil size were significant (p < 0.001, p < 0.001 respectively). The PCA ratios of the control group were $0.52{\pm}0.10$ before PE, $0.39{\pm}0.15$ after PE, and $0.43{\pm}0.15$ after PPV, respectively. Changes in pupil size after PE were significant (p = 0.011) but the change after PPV was not (p = 0.056). Conclusions: Intracameral epinephrine given after PE but before PPV effectively dilates the pupils during phacovitrectomy to treat PDR.

• Journal of Korean Ophthalmic Optics Society
• /
• v.18 no.2
• /
• pp.143-148
• /
• 2013

Purpose: The aim of this study was to investigate the distribution of age and gender, types of intraocular lens (IOL), and refractive errors in subjects who had cataract surgery. Methods: 2,217 subjects who had cataract surgery were surveyed at an optometry clinic in Chungbuk from 2010 to 2012. Information about IOL was obtained from case history, reflective and retroillumination images IOL by auto refracto-keratometer. Refractive errors were determined by objective and subjective refraction. Results: The mean age of the subjects was $71.74{\pm}10.62$ years. The number of cataract surgeries increased from 524 persons in 2010 to 888 persons in 2012. Of the subjects surveyed, 52 persons (2.3%) were under the 40 years of age, 144 persons (6.5%) were in 50s, 404 persons (18.2%) were in 60s, 1,132 persons (51.1%) were in 70s, 485 persons (21.9%) were in above 80s. Cataract surgery was significantly prevalent in more female (1,338 persons, 60.4%) than in male (879 persons, 39.6%). Types of IOL were 2,141 persons (96.6%) for monofocal lens, special IOLs such as multifocal, accommodative and toric lens were 76 persons (3.4%). The distribution of refractive errors after cataract operation were 1,588 eyes (38.5%) for simple myopic astigmatism, 327 eyes (7.9%) for simple hyperopic astigmatism, 601 eyes (14.6%) for mixed astigmatism, 1,240 eyes (30.0%) for myopia, 136 eyes (3.3%) for hyperopia, and 234 eyes (5.7%) for emmetropia. The uncorrected and best corrected visual acuity of the subjects were $0.55{\pm}0.25$ and $0.80{\pm}0.23$, respectively. Conclusions: The prevalence of cataract surgery increased with age until 70s years of age, it was more prevalent in men than women over 60s, and frequency of special types of IOL were low. Most cataract surgeries left residual refractive errors. Therefore even after cataract surgery it may need spectacles for better vision at either distance or near.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2012.01a
• /
• pp.55-58
• /
• 2012

백내장 수술에서 인공수정체 삽입영역을 표시하고 제어하는 것은 매우 중요하다. 수술시 발생하는 삽입영역 제어의 오차는 시력의 저하를 가져온다. 이를 위해 디지털 이미지 프로세싱을 이용한 많은 추적 방법이 연구 중에 있다. 그 중에서 템플릿 매칭은 실시간성이 뛰어난 객체 추적 방법으로 인공수정체 삽입 영역 추적 방법으로 사용 될 수 있다. 그러나 템플릿 매칭 방법은 입력 영상과 템플릿 영역의 상관관계만을 따지며 추적하기 때문에 추적 할 객체의 물체 겹침 상황이 발생하면 정확한 추적이 불가능하다. 본 논문에서는 템플릿 매칭 방법을 이용하여 인공수정체 삽입 영역을 추적하고 특정 영역의 버퍼들을 사용하여 물체 겹침 상황을 해결하고자 한다.

• Journal of the Korea Convergence Society
• /
• v.9 no.6
• /
• pp.99-106
• /
• 2018

The purpose of this study is to investigate incidence rates of complications in response to the introduction of quality evaluation of the DRG(diagnosis related group) payments, focusing on an increasing number of patients with lens surgery as the population aging increases.Fourthly, there were three dependent variables ('vitreous prolapse', 'IOP elevations', and 'other complications') in this study, and therefore multivariate logistic regression was performed. The result of the analysis indicates that as the number of hospitalized days increased, vitreous prolapse decreased to 0.27 times(95% CI 0.08~1.00) and IOP elevation decreased by 0.14 times(95% CI 0.03~1.59), compared to other complications, and this was statistically significant. From the above results, this study is meaningful in that it has compared the evaluation results of the appropriateness of DRG payment and the medical quality for lens surgery complications patients, in response to the introduction of quality evaluation by DRG payment.

• Radiation Oncology Journal
• /
• v.16 no.4
• /
• pp.517-529
• /
• 1998

Purpose : Although many studies have investigated the dosimetric aspects of stereotactic radiosurgery in terms of target volume, the absorbed doses at extracranial sites: especially the lens or thyroid - which are sensitive to radiation for deterministic or stochastic effect -have infrequently been reported. The aim of this study is to evaluate what effects the parameters of radiosurgery have on the absorbed doses of the lens and thyroid in patients treated by stereotactic radiosurgery, using a systematic plan in a humanoid phantom. Materials and Methods : Six isocenters were selected and radiosurgery was planned using the stereotactic radiosurgery system which the Department of Therapeutic Radiology at Seoul National University College of Medicine developed. The experimental radiosurgery plan consisted of 6 arc planes per one isocenter, 100 degrees for each arc range and an accessory collimator diameter size of 2 cm. After 250 cGy of irradiation from each arc, the doses absorbed at the lens and thyroid were measured by thermoluminescence dosimetry. Results : The lens dose was 0.23$\pm$0.08$\%$ of the maximum dose for each isocenter when the exit beam did not pass through the lens and was 0.76$\pm$0.12$\%$ of the maximum dose for each isocenter when the exit beam passed through the lens. The thyroid dose was 0.18$\pm$0.05$\%$ of the maximum dose for each isocenter when the exit beam did not pass through the thyroid and was 0.41$\pm$0.04$\%$ of the maximum dose for each isocenter when the exit beam Passed through the thyroid. The passing of the exit beam is the most significant factor of organ dose and the absorbed dose by an arc crossing organ decides 80$\%$ of the total dose. The absorbed doses of the lens and thyroid were larger as the isocenter sites and arc planes were closer to each organ. There were no differences in the doses at the surface and 5 mm depth from the surface in the eyelid and thyroid areas. Conclusion : As the isocenter and arc plane were placed closer to the lens and thyroid, the doses increased. Whether the exit beams passed through the lens or thyroid greatly influenced the lens and thyroid dose. The surface dose of the lens and thyroid consistently represent the tissue dose. Even when the exit beam passes through the lens and thyroid, the doses are less than 1$\%$ of the maximum dose and therefore, are too low to evoke late complications, but nevertheless, we should try to minimize the thyroid dose in children, whenever possible.

• Journal of Yeungnam Medical Science
• /
• v.24 no.2
• /
• pp.232-242
• /
• 2007

Background : The safety and efficacy of trabeculectomy with Mitomycin C (MMC) for surgical treatment in aphakic and pseudophaic eyes were retrospectively evaluated. Materials and Methods : The authors reviewed 51 eyes of 45 patients who had been followed up for at least 6 months after trabeculectomy using MMC for aphakic and pseudophakic eyes. The success rate and complications were analyzed. The success criteria included intraocular pressures of 21 mmHg or less with or without glaucoma medications and no loss of light perception. Surgical failure was defined as a postoperative loss of light perception in patients with preoperative vision better than light perception, additional glaucoma surgery, or phthisis bulbi in patients with preoperative vision of no light perception. Results : The average follow up period was 27.7 months and the intraocular pressure was controlled under 21 mmHg in 36 eyes of 51 (70.6%) after the procedure with or without medication for glaucoma. Using the Kaplan-Meier survival analysis, the cumulative success rate at the 3-, 6-, 12-, 24- and 36-month intervals were 98.0%, 94.1%, 91.9%, 83.4% and 75.5%, respectively. The complications observed were hyphema (4 eyes), serous choroidal detachment (4 eyes), hypotony (3 eyes), and endophthalmitis (1 eye). Conclusion : Trabeculectomy using Mitomycin C for the treatment of aphakic and pseudophaic eyes was safe and effective.

• Journal of Korean Ophthalmic Optics Society
• /
• v.18 no.3
• /
• pp.347-356
• /
• 2013

Purpose: To evaluate the visual acuity and visual performance after implantation of a aspheric multifocal (ReSTOR$^{(R)}$ SN6AD3) intraocular lens (IOL). Methods: Nineteen cataract patients (30 eyes) implanted with an aspheric multifocal IOL (ReSTOR$^{(R)}$ SN6AD3) either unilaterally or bilaterally were participated. Visual acuity (VA) and objective optical performance were evaluated at the time of preoperation, 1 week, 1 month, and 3 month after operation. At 3 month of post-operation, objective visual performance were measured and compared with the 38 eyes of 20 age-matched normal control. Distance VA was measured by using the ETDRS LCD chart and intermediate and near visual acuity were measured using Jaeger chart. Objective visual performance was assessed preoperatively and 1 week, 1 month and 3 month postoperatively using a double-pass system (Optical Quality Analysis System) with a 4-mm pupil diameter, the OSI (objective scatter index), MTF (modulation transfer function) cut off and strehl ratio. At 3 month of post-operation, visual acuity and visual performance compared with age matched normal control. Results: The uncorrected distance VA, OSI, MTF cut off and strehl ratio were significantly improved (p<0.05) until 1 month postoperatively. Visual performance of MTF cut off and strehl ratio after 3 month of operation were significantly improved compared to the normal control (p=0.063, p=0.103 respectively), however, OSI was higher than normal control. Patients implanted with aspheric multifocal IOL were satisfied with distance and near VA however, were unsatisfied with intermediate VA and reported glare and halos. Conclusions: The visual performance reaches to a stable condition in 1 month of implantation of aspheric multifocal IOL and improved to the level of age-mated normal patients. Also patients were satisfied with their quality of vision, however, intermediate VA, glare and halos were reported as complications.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.14 no.4
• /
• pp.173-179
• /
• 2014

Today, a surgery for cataract of Korean society frequently come to operation. A method for treating cataracts have been developed in various ways. Widely used method is a method to use the artificial lens and replace it with the existing lens. The surgery can be inserted exactly according to the angle and points that are calculated in advance in the intraocular lens insertion is important. However, The lens insertion point can delete or blur the display due to such factors as foreign material coming out of the eye during surgery. Therefore, The lens insertion point needs a method of tracking the image processing by receiving the camera images in real time display method. In this paper, we propose a feature point tracking method by using template matching and buffer. a simulation results show that our ideas can track a feature point of the intraocular lens insertion.

• Journal of The Korean Ophthalmological Society
• /
• v.60 no.5
• /
• pp.480-485
• /
• 2019

Purpose: We report a case of postoperative endophthalmitis in the cataract patient, associated with removal of an intralenticular foreign body that had remained in place without symptoms for 20 years. Case summary: A 45-year-old male visited our outpatient clinic complaining of gradual visual loss in his right eye over the past 3 months. In slit-lamp examinations, anterior capsular opacification, nuclear sclerosis, and posterior subcapsular opacity were observed in the right eye. Twenty years before, a tiny metallic projectile had hit his right eye, but slit-lamp examination at the time of injury did not reveal any intraocular foreign body. We decided to undergo cataract surgery. During phacoemulsification, a metallic foreign body was found in the lens and safely removed; then an intraocular lens was implanted. As hypopyon was evident 3 days later, we injected intravitreal antibiotics and applied fortified antibiotic eye drops to the right eye. The anterior chamber inflammation improved and the best-corrected visual acuity recovered to 1.0. Conclusions: Surgeon should be aware of that endophthalmitis could develop after cataract surgery with removal of an intralenticular foreign body that had been in place for 20 years. But did not trigger inflammation or cause any symptoms as the cataract progressed.