Cataract surgery following penetrating keratoplasty in children

Background: Following penetrating keratoplasty, cataract surgery warrants certain modifications to ensure maximum survival of the graft. Purpose: To emphasize the intraoperative challenges and surgical manipulations to be followed. Synopsis: The surgeon makes a superior sclerocorneal tunnel avoiding the graft host junction. Dispersive viscoelastic is used. Continuous curvilinear capsulorhexis is done. Cataractous lens aspirated with a low flow rate. The intraocular lens is placed in the bag. Superior peripheral iridectomy and primary posterior capsulorhexis are done. The wound closed with two interrupted 10�nylon sutures. Graft host junction integrity is maintained. Highlights: Ensure 1. Good intraoperative corneal visibility, 2. Avoid graft host junction for main port incision 3. Generous dispersive viscoelastic use/soft shell technique to protect the corneal endothelium, 4. Avoid phaco energy in case of soft cataracts/low phaco energy and flow rates, 5. Phaco probe to be meticulously oriented away from corneal endothelium, 6. Primary posterior capsulorhexis to be done as in any pediatric cataract surgery, 7. Make sure of the graft host junction integrity at the end of the surgery, 8. Restrict to a single port whenever possible.

Posterior capsular opacification and Nd:YAG capsulotomy rates in patients implanted with square-edged and non-square-edged intraocular lenses in manual small-incision cataract surgery: A randomized controlled study

Purpose: To study posterior capsular opacification (PCO) and neodymium?doped yttrium aluminum garnet (Nd:YAG) capsulotomy rates in patients implanted with square?edged and non?square?edged intraocular lenses (IOLs) in manual small?incision cataract surgery (MSICS). Setting: Tertiary eye care center. Design: Prospective, comparative, and randomized controlled study. Methods: This study included patients with senile cataracts scheduled for MSICS and IOL implantation. One eye of each patient was randomized to the implantation of square?edged (S group) or non?square?edged IOL (NSQ group). An independent observer analyzed PCO at 6, 12, 18, and 24 months under slit?lamp illumination. Results: A total of 104 eyes were included in this study. The mean age of the participants in the two groups was 63.2 (�2) years, and there were 65 (62.5%) men and 39 women (37.5%). The mean best?corrected visual acuity (BCVA) values at 6, 12, and 18 months were 0.157 (�10), 0.11 (�12), and 0.12 (�11), respectively, in the S group and 0.17 (�10), 0.17 (�12), and 0.20 (�17), respectively, in the NSQ group. At 12 (P = 0.03) and 18 months (P = 0.01) follow?up, the BCVA of the S group was significantly better than that of the NSQ group. Four eyes in the NSQ group and one eye in the S group required Nd:YAG. Conclusion: Evaluation of PCO and Nd:YAG capsulotomy rates showed that the 360� square of the posterior IOL edge plays a role in the prevention of PCO. Owing to the low cost of the material and the easy availability of IOLs manufactured from it, square?edged IOL has a definite role in the prevention of PCO in MSICS.

Incremental innovations in operation theaters

Background: The field of ophthalmology has been built upon continuous innovations. COVID?19 pandemic has been an important driving force behind many innovations in ophthalmology and other branches of medicine. Innovations in ophthalmology has been a key to surgical progress. The process of promoting innovation in surgery is imperative in the evolving practice of ophthalmology. Purpose: In this video we demonstrate some incremental innovations in operation theaters which help in increasing the efficiency and improving the performance of a surgeon. These innovations also provide a more comfortable environment for the patient undergoing the surgery. Synopsis: A few incremental innovations that are described in our video also help in preventing the spread of COVID infection during surgery. This video also showcases a few wet lab innovations that help train residents in their surgical skills. Highlights: Use and reuse of simple materials make it cost effective and ecofriendly. These incremental innovations help in the smooth running of operation theaters. Thus, they are small improvements in the existing setup and help in creating a smooth and error free OT flow

A novel two-surgeon technique of simultaneous bilateral cataract surgery with complete delinking

Though technological advancements have transcended beyond expectation, phacoemulsification remains a challenge in uncooperative patients, where the procedure may be contemplated under general anesthesia, with simultaneous bilateral cataract surgery (SBCS) being the surgery of choice. In this manuscript, we have reported a novel two-surgeon technique of SBCS on a 50-year-old mentally subnormal patient. Under general anesthesia, two surgeons performed phacoemulsification simultaneously, using two separate microscopes, irrigation lines, phaco machines, instruments, and assistants. Intraocular lens (IOL) implantation was performed in both eyes (OU). The patient had a visual recovery from 5/60, N36 in OU preoperatively to 6/12, N10 in OU on post-operative day 3 and 1 month, with no complications. This technique can potentially reduce the risk of endophthalmitis, repeated and prolonged anesthesia, and the number of hospital visits. To the best of our knowledge, this two-surgeon technique of SBCS has never been reported in the literature.

Role of swept-source anterior segment optical coherence tomography in imaging pediatric cataract

Purpose: To determine the morphology of pediatric cataracts and assess the status of the anterior and posterior capsules preoperatively on swept?source anterior segment optical coherence tomography (ASOCT) and compare the findings to those of intraoperative examination. Secondly, we aimed to obtain biometric measurements on ASOCT and compare them to those obtained on A?scan/optical methods. Methods: This was a prospective and observational study carried out at a tertiary care referral institute. ASOCT scans for anterior segment were obtained preoperatively for all patients, aged <8 years, scheduled for paediatric cataract surgery. The morphology of the lens and capsule and biometry were performed on ASOCT and the same were assessed intraoperatively. The main outcome measures were comparison of ASOCT findings to intraoperative findings. Results: The study included 33 eyes of 29 patients (range 3 months–8 years). The morphological characterization of cataract on ASOCT was accurate in 31/33 (94%) cases. ASOCT accurately identified fibrosis and rupture of the anterior and posterior capsules in 32/33 (97%) cases each. In 30% of eyes, ASOCT gave additional information preoperatively compared to the slit lamp. Intraclass correlation coefficient (ICC) calculation revealed a good agreement between the keratometry values obtained on ASOCT and those obtained preoperatively with a handheld/optical keratometer (ICC = 0.86, P = 0.001). Conclusion: ASOCT is a valuable tool that could provide complete preoperative information of the lens and capsule in pediatric cataract cases. In children as young as 3 months of age, intraoperative risks and surprises could be diminished. The keratometric readings are highly dependent on patient cooperation but show good agreement with the handheld/optical keratometer readings.

Retrospective analysis of the role of anterior segment optical coherence tomography and outcomes of cataract surgery in posterior polar cataract

Purpose: To evaluate the visual and surgical outcomes of cataract surgery in patients with posterior polar cataract (PPC) and to evaluate the benefits of preoperative anterior segment optical coherence tomography (AS?OCT). Methods: This was a retrospective, single?center study. Case records of patients diagnosed with PPC who underwent cataract surgery either by phacoemulsification or manual small?incision cataract surgery (MSICS) from January to December 2019 were analyzed. Data collected include demographic details, preoperative best corrected visual acuity (BCVA), AS?OCT, type of cataract surgery, intraoperative and postoperative complications, and visual outcome at 1?month follow?up. Results: One hundred patients were included in the study. Preoperative posterior capsular defect was noted on AS?OCT in 14 patients (14%). Seventy?eight underwent phacoemulsification and 22 underwent MSICS. Intraoperatively, posterior capsular rupture (PCR) was seen in 13 patients (13%) and cortex drop was noted in one among them (1%). Out of 13 PCRs, 12 were found to have posterior capsular dehiscence preoperatively in AS?OCT. The sensitivity of AS?OCT for detecting posterior capsule dehiscence was 92.3% and specificity was 97.7%. The positive predictive value and negative predictive value were 85.7% and 98.8%, respectively. There was no significant difference in the incidence of PCR between phacoemulsification and MSICS (P = 0.475). The mean BCVA at 1 month was found to be better with phacoemulsification than MSICS (P = 0.004). Conclusion: Preoperative AS?OCT has excellent specificity and negative predictive value in identifying posterior capsular dehiscence. It thus helps to plan the surgery and counsel patients appropriately. Both phacoemulsification and MSICS provide good visual outcome with similar complication rates.

Management of cataract in dry eye disease: Preferred practice pattern guidelines

Cataract surgery is one of the most commonly performed ophthalmic surgeries in the world. Dry eye disease (DED) is found to coexist in most patients with cataracts due to the overlapping age groups of both these conditions. Preoperative evaluation for DED is important to improve outcomes. A pre-existing DED affecting the tear film is likely to affect biometry. Moreover, special intraoperative considerations are needed in eyes with DED to reduce complications and improve postoperative outcomes. Dry eye disease (DED) is known to occur following an uneventful cataract surgery or a pre-existing DED is likely to worsen following cataract surgery as well. In these situations, despite a good visual outcome, patient dissatisfaction is common owing to the distressing DED symptoms. This review aims to summarize the preoperative, intraoperative, and postoperative considerations when performing cataract surgery in the presence of a coexisting DED.

Clinical outcome of diffractive multifocal lens versus monofocal lens in post-laser in situ keratomileusis patients: A retrospective, comparative study

Purpose: To compare the clinical outcomes of diffractive multifocal and monofocal lenses in post?laser in situ keratomileusis (LASIK) patients who underwent cataract surgery. Methods: This was a retrospective, comparative study of clinical outcomes that was conducted at a referral medical center. Post?LASIK patients who underwent uncomplicated cataract surgery and received either diffractive multifocal or monofocal lens were studied. Visual acuities were compared at baseline and postoperatively. The intraocular lens (IOL) power was calculated with Barrett True?K Formula only. Results: At baseline, both groups had comparable age, gender, and an equal distribution hyperopic and myopic LASIK. A significantly higher percentage of patients receiving diffractive lenses achieved uncorrected distance visual acuity (UCDVA) of 20/25 or better (80 of 93 eyes, 86% vs. 36 of 82 eyes, 43.9%, P = 1.0 x 105) and uncorrected near vision of J1 or better (63% vs. 0) compared to the monofocal group. The residual refractive error had no significant difference (0.37 ± 0.39 vs. 0.44 ± 0.39, respectively, P = 0.16) in these two groups. However, more eyes in the diffractive group achieved UCDVA of 20/25 or better with residual refractive error of 0.25–0.5 D (36 of 42 eyes, 86% vs. 15 of 24 eyes, 63%, P = 0.032) or 0.75–1.5 D (15 of 21 eyes, 23% vs. 0 of 22 eyes, P = 1.0 x 10?5) compared to the monofocal group. Conclusion: This pilot study shows that patients with a history of LASIK who undergo cataract surgery with a diffractive multifocal lens are not inferior to those who receive monofocal lens. Post?LASIK patients with diffractive lens are more likely to achieve not only excellent near vision, but also potentially better UCDVA, regardless of the residual refractive error.

Modified hydrodissection as a safe and effective treatment modality for rotating lens in cataract surgery

We describe in this article an effective and safe modification of hydrodissection technique in cataract surgery. The hydrodissection cannula tip is inserted into the capsulorhexis edge near the primary incision, with the cannula elbow resisting on the upper lip of the primary incision. Hydrodissection is then completed effectively and safely by squirting fluid to cleave the lens and capsular. This modified hydrodissection technique can be performed with high reproducibility and in a short practice period.

Improved visibility of illuminated chopper-assisted cataract surgery involving iris challenges

Purpose: The aim of this study was to evaluate the efficacy of the illuminated chopper?assisted cataract surgery in terms of shortening the surgical time and reducing the use of pupil expansion devices in eyes with iris challenges. Methods: This was a retrospective case series of a university hospital. Four hundred forty?three eyes of 433 consecutive patients who underwent illuminated chopper?assisted cataract surgery were included in this study. Cases with preoperative or intraoperative miosis, iris prolapse, and intraoperative floppy iris syndrome were included in the iris challenge group. Use of tamsulosin, iris hooks, pupil size, surgical time, and improved visibility (100/surgical time × pupil size) were compared between eyes with and without iris challenges. Mann–Whitney U test, Pearson’s Chi?square test, and Fisher’s exact test were used for statistical analysis. Results: Of 443 eyes, 66 were included in the iris challenge group (14.9%). Tamsulosin use was more common in patients with iris challenges and iris hooks were used more frequently (9.1% vs. 0%, P < 0.001) in patients with iris challenges than in those without iris challenges. Pupil size was smaller in patients with iris challenges (6.01 vs. 7.64 mm, P < 0.001). However, surgical time was not different (16.9 vs. 16.5 min, P = 0.064) between the two groups. As a result, improved visibility was calculated to be higher in patients with iris challenges (1.05 vs. 0.81, P < 0.001). Conclusion: In terms of surgical time and improved visibility, using the illuminated chopper simplified cataract surgery involving iris challenges. The use of an illuminated chopper is expected to be a good solution for challenging cataract surgeries.

Cataract versus combined surgery in pseudoexfoliation glaucoma

Purpose: Pseudoexfoliation glaucoma (XFG) is often associated with a higher rate of intraoperative complications and failure. This study aims to compare the long?term clinical and surgical outcomes of cataract surgery alone versus combined surgery in XFG. This was a retrospective comparative case series. Methods: All patients with XFG who underwent either cataract surgery alone [group 1: either phacoemulsification, PHACO/small?incision cataract surgery (SICS), n = 35] or combined surgery (group 2: phacotrabeculectomy, PHACOT or SICS + trabeculectomy, n = 46) from 2013 to 2018 by a single trained surgeon were screened and recalled for a detailed clinical examination, including Humphrey visual field analysis at 3?monthly intervals for a minimum of 3 years. Surgical success (intraocular pressure, IOP, <21 mm Hg and >6 mm Hg with (qualified success) or without medicines, complete success, survival rates, visual field changes, and need for additional procedures/medicines for IOP control were compared between groups. Results: A total of 81 eyes of 68 patients with XFG were included in this study (groups 1–35 eyes and groups 2–46 eyes each). Both groups achieved 27–40% IOP reduction from preoperative IOP levels, P < 0.001. Surgical success rates were similar in both groups (complete success 66% vs 55%, P = 0.4), qualified success 17% vs 24%, P = 0.8, in groups 1 and 2). Kaplan–Meier analysis showed a marginally better survival rate for group 1, 75% (55–87%), than group 2, 66% (50–78%), at 3 and 5 years which was not significantly different. The number of eyes that progressed at 5 years after surgery (5–6%) was similar in both groups. Conclusion: Cataract surgery can be as effective as combined surgery in XFG eyes with regards to final visual acuity, long?term IOP profile, and visual field progression, and complications/survival rates are comparable between the two procedures.

Incidencia y comportamiento clínico de la endoftalmitis poscirugía de catarata / Incidence and clinical behavior of endophthalmitis post cataract surgery

Introducción: La endoftalmitis posquirúrgica es la complicación más temida de la cirugía de catarata. Resulta potencialmente devastadora, puede amenazar seriamente la visión y tiene una incidencia estimada de entre 0,02 y 0,71 por ciento. Objetivo: Determinar la incidencia de endoftalmitis poscirugía de catarata y su comportamiento clínico. Métodos: Se realizó un estudio observacional, descriptivo y de corte transversal. Se revisaron 13 850 cirugías consecutivas de catarata realizadas en el Centro Oftalmológico del Hospital Universitario Clínico Quirúrgico "Arnaldo Milián Castro" de Villa Clara, Cuba. Resultados: La incidencia de endoftalmitis poscirugía de catarata en esta serie fue de 0,17 por ciento (IC 95 por ciento: 0,10-0,24 por ciento); 0,18 por ciento (IC 95 por ciento 0,11-0,25 por ciento) para extracción extracapsular del cristalino y sin incidencia en la facoemulsificación. La forma de presentación aguda fue más frecuente que la crónica; 0,13 por ciento (IC 95 por ciento: 0,07-0,19 por ciento) y 0,04 por ciento (IC 95 por ciento: 0,01-0,07 por ciento), respectivamente. Los hombres fueron más afectados que las mujeres y la edad media fue de 71,8 años. La forma aguda se presentó con una media de 5,1 días entre la cirugía y el inicio de los síntomas y la crónica con una media de 21,2 semanas. El 39,1 por ciento de los pacientes tuvo agudeza visual de percepción luminosa al momento del diagnóstico. Se reportó un crecimiento bacteriano en el 44,7 por ciento de las muestras, con una positividad en humor acuoso y vítreo del 42,1 por ciento y 47,4 por ciento, respectivamente. El Staphylococcus coagulasa negativo fue el germen más frecuente. Los antibióticos intravítreos más vitrectomía plana precoz fue la conducta terapéutica más empleada. Conclusiones: La incidencia de endoftalmitis poscirugía de catarata en esta serie está en el rango de lo reportado a nivel mundial. Se presenta comúnmente de forma aguda y con pobre agudeza visual. El agente etiológico aislado con más frecuencia fue el Staphylococcus coagulasa negativa(AU)

Introduction: Postoperative endophthalmitis is the most feared complication of cataract surgery. It is potentially devastating, can seriously threaten vision and has an estimated incidence of between 0.02 and 0.71 percent. Objective: To determine the incidence of endophthalmitis after cataract surgery and its clinical behavior. Methods: An observational, descriptive, cross-sectional, descriptive study was performed. Thirteen 850 consecutive cataract surgeries performed at the Ophthalmologic Center of the Clinical Surgical University Hospital "Arnaldo Milián Castro" of Villa Clara were reviewed. Results: The incidence of endophthalmitis after cataract surgery in this series was 0.17 percent (95 percent CI: 0.10-0.24 percent); 0.18 percent (95 percent CI: 0.11-0.25 percent) for extracapsular extraction of the crystalline lens and no incidence in phacoemulsification. The acute form of presentation was more frequent than the chronic form; 0.13 percent (95 percent CI: 0.07-0.19 percent) and 0.04 percent (95 percent CI: 0.01-0.07 percent), respectively. Males were more affected than females and the mean age was 71.8 years. The acute form occurred with a mean of 5.1 days between surgery and symptom onset and the chronic form with a mean of 21.2 weeks. Thirty-nine.1 percent of patients had visual acuity of light perception at the time of diagnosis. Bacterial growth was reported in 44.7 percent of the specimens, with positivity in aqueous and vitreous humor of 42.1 percent and 47.4 percent, respectively. Coagulase-negative Staphylococcus was the most frequent germ. Intravitreal antibiotics plus remission for early flat vitrectomy was the most commonly employed therapeutic behavior. Conclusions: The incidence of post cataract surgery endophthalmitis in this series is in the range of that reported worldwide. It commonly presents acutely and with poor visual acuity. The most frequently isolated etiologic agent was coagulase-negative Staphylococcus(AU)

Important signs to check posterior capsule integrity

For beginner surgeons, it is difficult to recognize the posterior capsule during cataract surgery. In the case of brown cataracts with a thin posterior capsule and in cataracts with asteroid hyalosis, it is difficult to identify the capsule before intraocular lens (IOL) implantation even for expert surgeons. Here we illustrate five important signs, which can be practiced in routine cases to make sure the posterior capsule is intact, before IOL implantation.

Comparison of topical steroids versus adjunctive intracameral triamcinolone versus posterior subtenon triamcinolone in pediatric cataract surgery

Purpose: Prolonged postoperative topical corticosteroids are commonly given after pediatric cataract surgery to control inflammation. This study was undertaken to compare the efficacy, safety, and compliance of postoperative topical steroids and adjunctive intracameral (I/C) triamcinolone acetonide (tricort) and posterior subtenon (PST) triamcinolone in modulating postoperative inflammation after surgery. Methods: Forty?eight eyes of children with pediatric cataract between the ages of 5 and 10 years were randomized into three equal groups (T, I, S) before surgery. Group T received postoperative topical 1% prednisolone tapered over 4 weeks; Group I received adjunctive intraoperative I/C 1.2 mg/0.03 ml tricort and topical 1% prednisolone for 2 weeks postoperatively, and Group S received a single 0.5 ml (40 mg/ ml) PST tricort without topical steroids. Signs of inflammation, intraocular pressure (IOP), and central corneal thickness were assessed at day 1, week 1, week 3, week 6, and week 12 postoperatively with optical coherence tomography (OCT) macula to rule out cystoid macular edema at the sixth and 12th weeks postoperatively. Results: Posterior synechiae were present in two eyes out of 16 in groups T and I, which resolved. Severe anterior chamber cells were present in four eyes out of 16 in group T, in two eyes in group I, and in one eye in group S, which resolved. All groups had comparable pre? and postoperative IOP. Conclusion: In pediatric cataracts, outcomes were better with PST tricort and the adjunctive I/C tricort compared to postoperative topical prednisolone, for modulating postoperative inflammation

Epithelial basement membrane dystrophy and cataract surgery / 国际眼科杂志(Guoji Yanke Zazhi)

Epithelial basement membrane dystrophy(EBMD)is a common anterior corneal dystrophy with hidden and easily missed clinical manifestations. Patients usually complain of mild blurred vision or foreign body sensation, or occasional pain at night or immediately after opening the eyelid in the morning. Slit-lamp examination revealed irregular, amorphous corneal surfaces, fingerprint-like linear lesions, and punctate or bubble-like lesions. EBMD has a significant impact on preoperative biometrics and intraocular lens power calculation, which can lead to inaccurate measurement and postoperative refractive accident, and cataract surgeons must be aware of this. This article reviews recent research and conference reports on the impact of EBMD on cataract surgery, as a reference for refractive cataract surgeons, thus improving the preoperative diagnosis and detection rate, so as to provide the optimal treatment plan for patients.

Effectiveness assessment of surgical simulator-based small-incision extracapsular cataract extraction training for young ophthalmologists / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the effectiveness of surgical simulator-based small-incision extracapsular cataract extraction training for young ophthalmologists.METHODS:Prospective and controlled study. A total of 48 young participants who had completed at least 3a standardized residency training or had obtained the attending certificate in the He Eye Specialist Hospital from 2020 to 2022 were enrolled. All the participants were randomly divided into simulator surgical operation training group(experimental group, n=24)and real animal eye operation training group(control group, n=24)after passing the theoretical training and assessment of small incision extracapsular cataract extraction. The participants in the experimental group and control group were trained with the surgical simulator and pig eyes respectively. After training, the overall effectiveness of training in both groups was rated using the simulator and pig eye operation was evaluated.RESULTS: The participants in the experimental group used less time than the participants in the control group on simulator assessment(all P&#x003C;0.05). The scores of injecting viscoelastics during keratonyxis, nucleus delivery and hydrate the paracentesis site steps were not different on simulator assessment between the two groups(P&#x003E;0.05). For the rest of the steps, the scores of experimental group were higher than those of the control group(all P&#x003C;0.05). Participants in the experimental group had significantly higher scores than control group on pig eye operation assessment(all P&#x003C;0.05). In the experimental group, the scores of the scleral groove dissection, tunnel dissection, continuous circular capsulorhexis, hydrodissection and hydro-prolapse and nucleus delivery steps had no significant difference between the surgical simulator and pig eye operation(P=0.068, 0.126, 0.960, 0.520, 0.206). The scores of injecting viscoelastics during keratonyxis, tunnel puncture into anterior chamber and hydrate the paracentesis site steps were significantly lower on simulator assessment than pig eye operation(P=0.007, 0.014, &#x003C;0.01). The scores of the cortex removal and intraocular lens(IOL)implantation were significantly higher on simulator assessment than eye of real animal(P=0.035, &#x003C;0.01).CONCLUSION:The application of surgical simulator on training small incision extracapsular cataract extraction skills for young ophthalmologists could significantly improve their skills in cataract surgery operation, providing a new mode and idea for the establishment of standardized cataract surgery training for young ophthalmologists.

Selection of intraocular lens calculation formula for cataract surgery in glaucoma patients / 国际眼科杂志(Guoji Yanke Zazhi)

Glaucoma and cataracts are the leading causes of blindness, and surgery is an important treatment option. Patients with glaucoma have clinical characteristics such as high intraocular pressure, shallow anterior chamber and short axial length, and the ocular structure is often altered after anti-glaucoma surgery like trabeculectomy. These changes also lead to differences in the accuracy of intraocular lens(IOL)refractive calculation between cataract surgery after anti-glaucoma surgery or combined glaucoma and cataract surgery and alone cataract surgery. Meanwhile glaucoma patients' individual clinical characteristics and structural changes caused by anti-glaucoma surgery have shown differences in the impact on the predictive accuracy of IOL diopters and the type of refractive drift. This article reviews the latest research advances in the causes of refractive error(RE), the characteristics of refractive drift, and the selection of the most appropriate IOL formula for glaucoma patients undergoing cataract surgery or cataract surgery after anti-glaucoma surgery or combined glaucoma and cataract surgery.

Clinical application and research progress of angle Kappa in ophthalmic surgery / 国际眼科杂志(Guoji Yanke Zazhi)

The human eye has various axes and angles, of which the angle Kappa is an important indicator of the centrality of the human eye and is widely used in ophthalmic surgery. Proper preoperative evaluation and application of the angle Kappa facilitated the achievement of optimal postoperative visual quality. Chord mu is a new term that has emerged recently to better express the angle Kappa. The two concepts are not well understood clinically, limiting their usefulness. Therefore, to better understand the angle Kappa and chord mu, the definitions and connections between them are presented separately in this paper. Meanwhile, the application of angle Kappa in strabismus surgery was summarized, the method for compensating large angle Kappa in corneal refractive surgery and the clinical significance of angle Kappa in predicting postoperative centrality of multifocal intraocular lens(MIOL)in phacoemulsification combined with MIOL implantation were discussed, with a view to providing references for clinical work.

Trifocal intraocular lens implantation to treat visual demands in Mongolian patients / Монголын Анагаах Ухаан

Introduction@#Intraocular lens (IOL) implants are monofocal and trifocal lenses which helps to clear up the vision after cataract surgery.@*Goal@#In this work, we aimed to compare the monofocal and trifocal IOL implantation during phacoemulsification surgery.@*Materials and Methods@#This study was conducted on 133 participants. Females comprised n=81, mean n=52 into equal groups. Preoperative and Postoperative cataract surgery UCVA and BCVA were measured and compared during the after 1 day, week 1, 2 weeks and month1. @*Statistical analysis@#The results of the study were processed using the SPSS 25.0 program after coding the data and checking for typographical errors. The normality of the data distribution was tested by inspecting a histogram. Categorical variables were compared using the chi-square test or Fisher's test. Statistical significance was determined at a p-value lower than 0.05@*Ethical statement@#The study was approved by the Research Ethics Committee of the Mongolian National University of Medical Sciences (No.2021/05/21). All patients provided written informed consent before participating in this study.@*Results@#The mean preoperative UCVA was 1.09±0.45D in monofocal IOL group, 0.99±0.49D in trifocal IOL group. At the first week: The mean postoperative UCVA at one week was 0.34±0.29D and 0.27±0.17D, in each group respectively. The mean postoperative BCVA in the first week was 0.28±0.27D and 0.20±0.15D in each group respectively. The mean postoperative UCVA at 1 month was 0.27±0.24D and 0.15±0.16D in each group, while BCVA was 0.26±24.94D and 0.06±0.63D.There was a highly significant statistical difference between the result of UCVA preoperative and the results of UCVA at the early and last postoperative follow up. @*Conclusion@#From our results, the best corrected visual acuity and was better for Trifocal group than Monofocal group. It is evident that post-operative near UCVA and BCVA was statistically significant at monofocal and trifocal groups.

Femtosecond laser-assisted cataract phacoemulsification combined with Toric intraocular lenses implantation in correction of high myopia cataract and corneal astigmatism / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To measure the indexes including postoperative distance, middle, near visual acuity and near stereopsis vision of patients with high myopia cataract and corneal astigmatism by femtosecond laser, which can quantify the diameter of capsulorhexis opening, and to evaluate the availability and necessity of Toric intraocular lenses(IOL)in high myopia.METHODS: Prospective case-control study. Patients with binocular high myopia cataract and corneal astigmatism who undergone femtosecond laser-assisted cataract surgery in our hospital were selected, and they were divided into two groups, with 20 cases(40 eyes)in group A(Toric IOL)and 20 cases(40 eyes)in group B(IQ IOL). Indexes, including preoperative corneal astigmatism and spherical equivalent and best-corrected distance visual acuity, uncorrected middle visual acuity, uncorrected near visual acuity, residual refractive astigmatism, near stereopsis acuity, total high-order aberration and total spherical aberration, were measured postoperatively at 7d, 1 and 3mo.RESULTS: The uncorrected middle and near visual acuity, Titmus near stereopsis acuity and residual astigmatism at 7d, 1 and 3mo after surgery were significantly improved in the Toric IOL group than the non-Toric group(all P&#x0026;#x003C;0.05). The dependence on glasses was reduced. The postoperative best-corrected distance visual acuity, total high-order aberration and total spherical aberration of the two groups showed no statistically significant differences(all P&#x0026;#x003E;0.05).CONCLUSIONS: The implantation of Toric IOL in patients with high myopia cataract and corneal astigmatism can effectively correct corneal astigmatism, improve postoperative uncorrected middle and near visual acuity and near stereopsis visual function, reduce postoperative dependence on glasses and enhance binocular stereopsis visual function.