Classification of congenital cataracts based on multidimensional phenotypes and its association with visual outcomes.

AIM: To establish a classification for congenital cataracts that can facilitate individualized treatment and help identify individuals with a high likelihood of different visual outcomes. METHODS: Consecutive patients diagnosed with congenital cataracts and undergoing surgery between January 2005 and November 2021 were recruited. Data on visual outcomes and the phenotypic characteristics of ocular biometry and the anterior and posterior segments were extracted from the patients' medical records. A hierarchical cluster analysis was performed. The main outcome measure was the identification of distinct clusters of eyes with congenital cataracts. RESULTS: A total of 164 children (299 eyes) were divided into two clusters based on their ocular features. Cluster 1 (96 eyes) had a shorter axial length (mean±SD, 19.44±1.68 mm), a low prevalence of macular abnormalities (1.04%), and no retinal abnormalities or posterior cataracts. Cluster 2 (203 eyes) had a greater axial length (mean±SD, 20.42±2.10 mm) and a higher prevalence of macular abnormalities (8.37%), retinal abnormalities (98.52%), and posterior cataracts (4.93%). Compared with the eyes in Cluster 2 (57.14%), those in Cluster 1 (71.88%) had a 2.2 times higher chance of good best-corrected visual acuity [<0.7 logMAR; OR (95%CI), 2.20 (1.25-3.81); P=0.006]. CONCLUSION: This retrospective study categorizes congenital cataracts into two distinct clusters, each associated with a different likelihood of visual outcomes. This innovative classification may enable the personalization and prioritization of early interventions for patients who may gain the greatest benefit, thereby making strides toward precision medicine in the field of congenital cataracts.

Ocular development in children with unilateral congenital cataract and persistent fetal vasculature.

AIM: To investigate the ocular development of patients who had unilateral congenital cataract (CC) combined with persistent fetal vasculature (PFV). METHODS: This cross-sectional, observational study included patients who had unilateral CC and PFV and those with isolated unilateral CC. Axial length (AL), keratometry, anterior chamber depth (ACD), lens thickness, and vitreous length were obtained. The ocular biometric parameters of the affected eyes of patients with CC and PFV were compared with the fellow eyes and with the affected eyes of patients with isolated CC. RESULTS: A total of 110 patients were included and divided into 4 groups: group 1 (18 patients with CC and PFV, <24mo), group 2 (22 patients with CC and PFV, ≥24mo), group 3 (35 patients with CC, <24mo), and group 4 (35 patients with CC, ≥24mo). The ALs of the affected eyes were shorter than those of the fellow eyes in group 1 (20.02±1.06 vs 20.66±0.63 mm, P=0.025). While the ALs of the affected eyes were longer than those of the fellow eyes in group 2 (23.18±2.00 vs 22.31±1.06 mm, P=0.044) and group 4 (22.64±1.80 vs 22.02±1.01 mm, P=0.033). The keratometries of the affected eyes were steeper than those of the fellow eyes in group 2 (44.78±1.66 vs 43.83±1.38 D, P=0.041) and group 4 (43.76±1.91 vs 43.34±1.46 D, P=0.043). No difference of ACDs between two eyes was found in all groups (all P>0.05). CONCLUSION: Compared with the fellow eyes, the ALs of the eyes with unilateral CC and PFV are shorter in patients younger than 24mo and longer in those older than 24mo; the keratometries of the eyes with unilateral CC and PFV are steeper in patients older than 24mo and similar with those younger than 24mo. These findings provide further understanding of ocular development in patients with both CC and PFV.

Effectiveness of surgical management of malignant glaucoma in phakic eyes.

AIM: To assess the effectiveness of core vitrectomy-phacoemulsification-intraocular lens (IOL) implantation-capsulo-hyaloidotomy in treating phakic eye at least 1mo after the onset of malignant glaucoma. METHODS: A retrospective analysis were performed on malignant glaucoma patients treated in Zhongshan Ophthalmic Center between 2016 and 2018. Demographic and clinical data were described. The preoperative and postoperative visual acuity (VA), intraocular pressure (IOP), number of IOP-lowering medications used, and anterior chamber depth (ACD) of the case series were compared by Wilcoxon signed-rank test. RESULTS: Thirteen phakic eyes with long time intervals between onset and surgery were identified in this case series. Core vitrectomy-phacoemulsification-IOL implantation-capsulo-hyaloidotomy reduced the IOP (P=0.046) and the number of IOP-lowering medications used (P=0.004), deepened the ACD (P=0.005). Complete success was achieved in 38.5% of the eyes, and anatomical success was achieved in 100% of the eyes without any recurrence. The only postoperative complication observed is corneal endothelial decompensation. It occurred in two cases. CONCLUSION: Core vitrectomy-phacoemulsification-IOL implantation-capsulo-hyaloidotomy is safe and effective for treatment of long onset phakic malignant glaucoma.

Screening and identifying hepatobiliary diseases through deep learning using ocular images: a prospective, multicentre study.

BACKGROUND: Ocular changes are traditionally associated with only a few hepatobiliary diseases. These changes are non-specific and have a low detection rate, limiting their potential use as clinically independent diagnostic features. Therefore, we aimed to engineer deep learning models to establish associations between ocular features and major hepatobiliary diseases and to advance automated screening and identification of hepatobiliary diseases from ocular images. METHODS: We did a multicentre, prospective study to develop models using slit-lamp or retinal fundus images from participants in three hepatobiliary departments and two medical examination centres. Included participants were older than 18 years and had complete clinical information; participants diagnosed with acute hepatobiliary diseases were excluded. We trained seven slit-lamp models and seven fundus models (with or without hepatobiliary disease [screening model] or one specific disease type within six categories [identifying model]) using a development dataset, and we tested the models with an external test dataset. Additionally, we did a visual explanation and occlusion test. Model performances were evaluated using the area under the receiver operating characteristic curve (AUROC), sensitivity, specificity, and F1* score. FINDINGS: Between Dec 16, 2018, and July 31, 2019, we collected data from 1252 participants (from the Department of Hepatobiliary Surgery of the Third Affiliated Hospital of Sun Yat-sen University, the Department of Infectious Diseases of the Affiliated Huadu Hospital of Southern Medical University, and the Nantian Medical Centre of Aikang Health Care [Guangzhou, China]) for the development dataset; between Aug 14, 2019, and Jan 31, 2020, we collected data from 537 participants (from the Department of Infectious Diseases of the Third Affiliated Hospital of Sun Yat-sen University and the Huanshidong Medical Centre of Aikang Health Care [Guangzhou, China]) for the test dataset. The AUROC for screening for hepatobiliary diseases of the slit-lamp model was 0·74 (95% CI 0·71-0·76), whereas that of the fundus model was 0·68 (0·65-0·71). For the identification of hepatobiliary diseases, the AUROCs were 0·93 (0·91-0·94; slit-lamp) and 0·84 (0·81-0·86; fundus) for liver cancer, 0·90 (0·88-0·91; slit-lamp) and 0·83 (0·81-0·86; fundus) for liver cirrhosis, and ranged 0·58-0·69 (0·55-0·71; slit-lamp) and 0·62-0·70 (0·58-0·73; fundus) for other hepatobiliary diseases, including chronic viral hepatitis, non-alcoholic fatty liver disease, cholelithiasis, and hepatic cyst. In addition to the conjunctiva and sclera, our deep learning model revealed that the structures of the iris and fundus also contributed to the classification. INTERPRETATION: Our study established qualitative associations between ocular features and major hepatobiliary diseases, providing a non-invasive, convenient, and complementary method for hepatobiliary disease screening and identification, which could be applied as an opportunistic screening tool. FUNDING: Science and Technology Planning Projects of Guangdong Province; National Key R&D Program of China; Guangzhou Key Laboratory Project; National Natural Science Foundation of China.

Visual outcomes of surgical and conservative treatment in children with small posterior polar cataracts and posterior lenticonus.

AIM: To compare the visual outcomes of children with small (≤3 mm) posterior polar cataracts (PPC) and posterior lenticonus who had cataract extraction surgery with the visual outcomes of those who were managed conservatively. METHODS: Children who initially had small PPC and posterior lenticonus who were followed up over 1-year period were retrospective reviewed in the study. Patients receiving surgery were compared with those receiving conservative therapy. The axial length, keratometry, refraction, best-corrected visual acuity (BCVA), and strabismus measurements were recorded. Lens morphology, i.e., the location, size, and depth of the cataract lesion, was measured with a Scheimpflug imaging system. To help control for baseline differences in the groups, patients were matched with controls by propensity score methodology. RESULTS: The study evaluated 60 patients (30 in the surgery group and 30 in the conservative therapy group) after matching by propensity score. Patients who underwent cataract surgery showed greater BCVA improvements (0.36±0.24 logMAR) than patients who were treated without surgery (0.22±0.26 logMAR; P=0.036). Surgery was effective in patients with a rear projection length (RPL) less than 1.0 mm and a pretreatment BCVA worse than 0.52 logMAR. CONCLUSION: Children with small PPC and posterior lenticonus who undergo cataract surgery experience greater BCVA improvements than those managed conservatively. Certain patients presenting with a RPL less than 1.0 mm and a pretreatment BCVA of 0.52 logMAR or worse may benefit from surgery.

Dynamic profile of ocular refraction in pediatric cataract patients after lens surgeries.

AIM: To study the change in ocular refraction in patients with pediatric cataracts (PCs) after lens extraction. METHODS: A total of 1258 patients who were undergoing cataract extraction with/without intraocular lens (IOL) implantation were recruited during preoperative examinations between Jan 2010 and Oct 2013. Patient ages ranged from 1.5mo to 14y. Follow-ups were conducted at 1wk, 1, and 3mo postoperatively and every 3mo in the first year, then 6mo thereafter. Ocular refraction [evaluated as spherical equivalent (SE)] and yearly myopic shift (YMS) were recorded and statistically analyzed among patients with age at surgery, baseline ocular refraction, gender, postoperative time and laterality (bilateral vs unilateral). RESULTS: By Dec 31st 2015, 1172 participants had been followed for more than 2y. The median follow-up period was 3y. The critical factors affecting the ocular refraction of PC patients were baseline ocular refraction, postoperative time for both aphakic and pseudophakic eyes. YMS grew most rapidly in young childhood and early adolescence. CONCLUSION: After lens surgeries, ocular refraction in PC patients shows an individual difference of change. Further concerns should be raising to monitor the rapid myopic shift at early adolescence of these patients.

Increased prevalence of parent ratings of ADHD symptoms among children with bilateral congenital cataracts.

AIM: To investigate the behavioral and psychological disorders and the prevalence of parent ratings of attention deficit hyperactivity disorder (ADHD) symptoms among children with bilateral congenital cataracts (CCs). METHODS: This cross-sectional study investigated children with bilateral CC aged 3-8y (CC group) using Conners' Parent Rating Scale-48 (CPRS-48) from July to December 2016. The abnormal rates of psychological symptoms in CC children and normal vision (NV) children were compared using the Chi-square test. The scores of CC children were compared with those of NV children and the Chinese urban norm using the independent samples t-test and one-sample t-test, respectively. RESULTS: A total of 262 valid questionnaires were collected. The ratio of CC children to NV children was 119:143. The overall rate of psychological symptoms in CC children was 2.28 times higher than that in NV children (46.22% vs 20.28%, Pearson's χ 2=20.062; P<0.001). CC children showed higher scores for conduct problems, learning problems, impulsiveness/hyperactivity, anxiety, and hyperactivity index than NV children and the Chinese urban norm, particularly between the ages of 3 and 5y. Furthermore, male children aged between 6 and 8y showed a higher impulsive/hyperactive score than females of the same age (t=6.083, P<0.001). CONCLUSION: Children with bilateral CCs have a higher rate of ADHD symptoms than children with NV. This study provides clinical evidence that screening for psychological symptoms and particularly for ADHD symptoms in children with bilateral CC are recommended for an early diagnosis and timely treatment.

Novel mutation in OCRL leading to a severe form of Lowe syndrome.

AIM: To investigate the phenotype and genotype of a family with X-linked recessive Lowe syndrome. METHODS: All the members in the Chinese pedigree underwent comprehensive ophthalmologic and systemic examinations. Genomic DNA was isolated from peripheral blood of the pedigree members and 100 unrelated healthy Chinese subjects. Direct sequencing was performed to screen the exons and intron boundaries of OCRL. RESULTS: The ophthalmological and systemic examinations suggested that the affected individual had Lowe syndrome. The phenotype in the pedigree is severe and consistent among all the affected individuals except for an individual who additionally suffered from congenital heart disease and laryngeal cartilage dysplasia. Directional Sanger sequencing identified a complex mutation c.(2368_2368delG; c.2370A>C) in the Rho-GTPase activating protein domain. This complex mutation causes termination of protein synthesis at amino acid 824 and result in a new peptide with 823 amino acids (p.Ala790ProfsX34). This mutation was not detected in 100 unrelated healthy Chinese subjects. CONCLUSION: Our findings expand the phenotypic and genotypic spectrum of Lowe syndrome.

Timing and approaches in congenital cataract surgery: a four-year, two-layer randomized controlled trial.

AIM: To compare visual prognoses and postoperative adverse events of congenital cataract surgery performed at different times and using different surgical approaches. METHODS: In this prospective, randomized controlled trial, we recruited congenital cataract patients aged 3mo or younger before cataract surgery. Sixty-one eligible patients were randomly assigned to two groups according to surgical timing: a 3-month-old group and a 6-month-old group. Each eye underwent one of three randomly assigned surgical procedures, as follows: surgery A, lens aspiration (I/A); surgery B, lens aspiration with posterior continuous curvilinear capsulorhexis (I/A+PCCC); and surgery C, lens aspiration with posterior continuous curvilinear capsulorhexis and anterior vitrectomy (I/A+PCCC+A-Vit). The long-term best-corrected visual acuity (BCVA) and the incidence of complications in the different groups were compared and analyzed. RESULTS: A total of 57 participants (114 eyes) with a mean follow-up period of 48.7mo were included in the final analysis. The overall logMAR BCVA in the 6-month-old group was better than that in the 3-month-old group (0.81±0.28 vs 0.96±0.30; P=0.02). The overall logMAR BCVA scores in the surgery B group were lower than the scores in the A and C groups (A: 0.80±0.29, B: 1.02±0.28, and C: 0.84±0.28; P=0.007). A multivariate linear regression revealed no significant relationships between the incidence of complications and long-term BCVA. CONCLUSION: It might be safer and more beneficial for bilateral total congenital cataract patients to undergo surgery at 6mo of age than 3mo. Moreover, with rigorous follow-up and timely intervention, the postoperative complications in these patients are treatable and do not compromise visual outcomes.

The effect of cataract surgery on sleep quality: a systematic review and Meta-analysis.

AIM: To evaluate the effect of cataract surgery on sleep quality and to compare the difference between ultraviolet-blocking clear intraocular lens (UVB-IOL) and blue-filtering intraocular lens (BF-IOL) implantation. METHODS: Electronic search was performed of PubMed, MEDLINE, Embase and the Cochrane Library up to January 2016. Studies were eligible when they evaluated the sleep quality before and after cataract surgery by Pittsburgh sleep quality index (PSQI). A random/fixed-effects Meta-analysis was used for the pooled estimate. Heterogeneity was assessed with the I2 test. RESULTS: Six studies were selected from 5623 references. Cataract surgery significantly reduced the PSQI scores at postoperative 0-3mo [mean difference (MD) =-0.62, 95%CI: -1.14 to -0.11, P=0.02, I2=66%] and 3-12mo (MD=-0.32, 95%CI: -0.62 to -0.02, P=0.04, I2=0), respectively. Considering different intraocular lens (IOL) implantations, relative post-operative PSQI reduction was found for both UVB-IOL and BF-IOL, but a significant reduction was detected only for UVB-IOL. No significant difference was found with the effect of BF-IOL vs UVB-IOL on sleep quality. CONCLUSION: This study found that cataract surgery significantly improved the PSQI score-derived subjective sleep quality irrespective of the IOL type implanted. These findings highlight a substantial benefit of cataract surgery on systemic health with photoreceptive restoration in addition to visual acuity improvements.

Age-related reduction in calbindin-D28K expression in the Sprague-Dawley rat lens.

Calcium levels in the lens rise with increasing age and increased intracellular calcium accumulation is known to be a risk factor for cataract formation. Calbindin-D28K (CALB1) is an intracellular calcium buffer. It is not clear whether CALB1 levels change in response to the Ca2+ accumulation in the lens that occurs with age. The present study investigated the distribution of CALB1 in the lenses of Sprague-Dawley (SD) rats and whether this changed with age. Lenses were isolated from SD rats at 1, 6, 12 and 18 months of age. CALB1 distribution was examined using immunohistochemistry. Lens epithelial cells were counted in median sagittal plane slices from the hematoxylin and eosin-stained lens and quantified using western blot analysis. Calb1 gene expression was examined using reverse transcription-quantitative polymerase chain reaction. CALB1 was distributed in the epithelial and fiber cells of the lens. CALB1 levels declined significantly with increasing age, whilst there was no significant accompanying decrease in the number of lens cells. A similar reduction was noted in CALB1 mRNA levels. To the best of our knowledge, this is the first study to demonstrate that CALB1 expression and CALB1 protein levels in SD rat lens decrease with age. This reduction does not reflect a reduction in lens cell numbers but a genuine reduction in gene expression within these cells. Thus, CALB1 may be important in changes occurring in the lens in older age, in particular in the development of cataracts.

[Clinical research of anterior chamber inflammation after phacoemulsification surgery in patients with complicated cataract secondary to uveitis].

OBJECTIVE: To investigate anterior chamber inflammation after phacoemulsification with intraocular lens (IOL) implantation in patients with Vogt-Koyanagi-Harada (VKH) syndrome or Behçet's disease (BD). METHODS: Cohort study. Seventeen patients (20 eyes) with complicated cataracts and VKH syndrome or BD who underwent phacoemulsification with IOL implantation at Zhongshan Ophthalmic Center, Sun Yat-Sen University (SYSU) between January 2010 and June 2011 were included as the experimental group in this study. Cataract surgery was performed on these patients only when uveitis had been under control for more than three months. Thirty patients (40 eyes) with age-related cataracts who underwent phacoemulsification with IOL implantation in the same period were included as the control group. Quantitative measurements of anterior chamber aqueous flare and inflammatory cells were conducted preoperatively and postoperatively using a Laser Flare Cell Meter (LFCM). Independent t-test was used to compare patients' ages, and the energy and time of phacoemulsification between the two groups. The Student's t-test was used to assess the differences between paired data preoperatively and postoperatively. Independent t-test was also used to assess the quantitative data between groups. RESULTS: The study recruited 20 eyes in the experimental group and 40 eyes in the control group, including 11 eyes from 9 VKH patients and 9 eyes from 8 BD patients. The preoperative and postoperative flare values in the experimental group were (19.86 ± 6.47), (44.28 ± 18.47), (35.60 ± 12.65), (23.85 ± 8.41), and (13.86 ± 4.27) pc/ms, respectively, which were statistically higher than that of the control group preoperatively, and on days 1, 7, 30, and 90 after surgery (tpre = 4.643, Ppre < 0.01; t1 = 6.035, P1 < 0.01; t7 = 3.595, P7 = 0.001; t30 = 4.658, P30 < 0.01; t90 = 3.308, P90 = 0.002). Aqueous flare in Group A and Group B declined to preoperative levels on day 30 (t = 0.320, P = 0.753) and day 7 (t = 0.454, P = 0.653). For the experimental group, the inflammatory cell count on day 1 and 7 was (83.46 ± 27.08) and (27.56 ± 8.32) cells/0.5 mm(3), respectively, which was significantly higher than the preoperative level [(6.47 ± 3.56)cells/ 0.5 mm(3), t1 = 5.261, P1 < 0.01; t7 = 2.766, P7 = 0.012]. On days 30 and 90, the inflammatory cell count was (11.43 ± 4.81) and (4.82 ± 2.29) cells/0.5 mm(3), respectively, and there was no statistically significant difference in the inflammatory cell count compared with the preoperative level (t30 = 2.348, P30 = 0.042; t90 = 1.376, P90 = 0.186). For the control group, inflammatory cell count reduced to pre-operative level on day 7 (t7 = 2.464, P7 = 0.018). CONCLUSIONS: Anterior chamber inflammation reaches peak levels one week postoperatively in VKH and BD patients who receive phacoemulsification with IOL implantation. It takes three months for the inflammation to recede, and might take longer for complete restoration of the blood-aqueous barrier.

Eye health is everyone's responsibility: China's first Western-style eye hospital improves in the prevention of blindness.

AIM: To investigate the relationship between China's first Western-style eye hospital development and the prevention of blindness in China and determine the main factor influencing eye health today. METHODS: Data about eye health, blindness and cataract surgery rate of China from public website of World Health Organization (WHO), ORBIS International, Ministry of Health (MOH) of China, Pubmed center and Historical Archives of Zhongshan Ophthalmic Center (ZOC) were reviewed and analyzed. RESULTS: ZOC is China's first Western-style eye hospital. In 2012, the ORBIS Flying Eye Hospital has chosen ZOC once again as one of its destinations, 30 years after ORBIS expanded internationally to train eye care professionals and treat underserved patients in developing countries in 1982. During the past 30 years, cataract surgery rate and public awareness of blindness prevention were improved greatly in China, in which ZOC plays a very important role. CONCLUSION: ZOC, as China's first Western-style eye hospital, has improved in the prevention of blindness. Eye health has become everyone's responsibility.

Clinical evaluation of two multifocal intraocular lens implantation patterns.

AIM: To evaluate the visual outcomes and patient satisfaction of two multifocal intraocular lens implantation patterns, with the decision between the two patterns being guided by the patients' choice of visual zones that best suited their lifestyle, or lifestyle zones. METHODS: This is a prospective non-randomized comparative study. The lifestyle zones of 32 consecutive age-related cataract patients (64 eyes) were investigated individually to guide the surgical decision between two multifocal intraocular lens implantation patterns. The first group (MIX) received a combined implantation of a ReZoom NXG1 lens in the dominant eye and a Tecnis ZM900 lens in the other eye. The second group (MATCH) received bilateral ReZoom NXG1 lenses. One year postoperatively, the patients were assessed for binocular uncorrected visual acuity, reading visual acuity, reading speed and depth of focus under different luminance and were surveyed for visual disturbances, satisfaction and complete spectacle independence. RESULTS: According to the determination of lifestyle zones, 18 and 14 patients were included in the MIX and MATCH groups, respectively. One year postoperatively, each of the patients exhibited positive visual outcomes and lifestyle satisfaction, although there were still some differences between the two groups. Generally, patients in the MATCH group had better distance visual acuity than those in the MIX group. In contrast, patients in the MIX group had better near visual acuity, better reading acuity and better reading speed than those in the MATCH group. Between the two groups, there was no clear difference in intermediate visual acuity, and the depths of focus between the two groups were approximately equal. The results of the mean NEI-RQL-42 questionnaire score, overall satisfaction, and complete spectacle independence did not differ between the two groups. CONCLUSION: Different multifocal intraocular lenses implantation patterns can have differing advantages and disadvantages; however, the best results with respect to visual outcome and patient satisfaction can be achieved by taking individual lifestyle zones into account.

Clinical evidence in concurrence of retinitis pigmentosa and glaucoma.

Glaucoma is rarely complicated by retinitis pigmentosa (RP). To provide clinical evidences for this rare situation, we report the concurrence of these two diseases in two children of a Chinese family. In the present two-child Chinese family without positive history, the older sister presented with bilateral sector RP and coexisting chronic angle-closure glaucoma, and the brother with bilateral whole RP but without coexisting glaucoma. Clinical evidences in concurrence of variants of RP and glaucoma because of possible different gene mutations from the same genetic background represent a rare situation, which may provide clues for future researches in molecular pathogenesis of these rare diseases.

Anterior segment variations with age and accommodation demonstrated by slit-lamp-adapted optical coherence tomography.

OBJECTIVE: To investigate anterior segment variations with age and accommodation by slit-lamp-adapted optical coherence tomography (SL-OCT) and determine a safe central vault distance between the implantable contact lens (ICL) and the crystalline lens to avoid contact cataract formation. DESIGN: Evaluation of diagnostic test or technology. PARTICIPANTS: Eighty-six patients (126 eyes) under regular review from the Optometry Clinic and Outpatient Department in Zhongshan Ophthalmic Center. METHODS: Patients underwent anterior segment measurements, such as anterior chamber depth (ACD), anterior chamber width (ACW), crystalline lens rise (CLR), and pupil diameter (PD), with the SL-OCT system manufactured by Heidelberg Engineering GmbH, Heidelberg, Germany. Data were analyzed with SPSS software (version 16.0, SPSS, Inc., Chicago, IL). MAIN OUTCOME MEASURES: Anterior segment parameters and their variations with age and accommodation. RESULTS: The internal vertical ACW (V-ACW) was anatomically larger than the internal horizontal ACW (H-ACW). With age, the ACD decreased approximately 17 µm per year. Forward movement of the crystalline lens' anterior pole decreased approximately 11 µm per year. During physiologic accommodation, the variation in ACD was -24 µm per diopter and the alterations in CLR were 28 µm per diopter. According to our data, a safe lens vault after phakic intraocular lens implantation should be more than 300 µm to reduce complications. CONCLUSIONS: Slit-lamp-adapted optical coherence tomography is a user-friendly instrument for evaluating the anterior segment, especially for accurate anterior chamber biometry, and may offer guidance on minimizing touch and cataract formation after phakic intraocular lens implantation.

Reconstruction of orbital defect in rabbits with composite of calcium phosphate cement and recombinant human bone morphogenetic protein-2.

BACKGROUND: Calcium phosphate cement (CPC) is a biocompatible and osteoconductive bone substitute, and recombinant human bone morphogenetic protein-2 (rhBMP-2) has strong osteoinductibility, therefore we developed a composite bone substitute with CPC and rhBMP-2 and evaluate its reconstruction effect in rabbit orbital defect. METHODS: Thirty-six rabbits were randomly divided into two groups and a 5 mm × 5 mm × 2 mm bone defect in the infraorbital rim was induced by surgery in each orbit (72 orbits in all). The orbital defects were treated with pure CPC or composite of CPC and rhBMP-2. The osteogenesis ability of different bone substitute was evaluated by gross observation, histological examination, histomorphometrical evaluation, compressive load-to-failure testing, and scanning electron microscope (SEM). RESULTS: Gross observation showed that both bone substitutes were safe and effective for reconstruction of orbital defect. However, histological examination, histomorphometrical evaluation and SEM showed that CPC/rhBMP-2 group had faster speed in new bone formation and degradation of substitute material than CPC group. Compressive load-to-failure testing showed that CPC/rhBMP-2 group had stronger compressive strength than CPC group at every stage with significant difference (P < 0.05). CONCLUSION: Composite of CPC/rhBMP-2 is an ideal bioactive material for repairing orbital defect, with good osteoconductibility and osteoinductibility.

[Exploration of lymphangiogenesis in alkali burned human cornea].

OBJECTIVE: To explore the lymphangiogenesis process in alkali burned human cornea and to discuss factors modulating this process. METHODS: It was a retrospective case series study. Twenty-two cases (22 eyes) of hospitalized patients suffering from alkali burned cornea and requiring keratoplasty from January to December 2005 were analyzed retrospectively. Before surgery, injury time (IT) and injury degree (ID) were recorded. Furthermore, inflammation index (II) and relative area of new blood vessels (BVA) were measured. Cornea specimens were assessed for lymphatic vessel counting (LVC) and blood vessel counting (BVC) via immunohistochemical staining and transmission electronic microscopy. Meanwhile, HE staining was also performed to observe infiltration of polymorphonuclear (PMN) leucocytes in corneal tissues. Student t-test, Pearson correlation test and Stepwise regression analysis were used to investigate the influencing factors. RESULTS: In these 22 cases, IT was (57.62 +/- 31.72) months; ID was (12.00 +/- 2.76) scores; II was (2.32 +/- 2.63) scores; BVA was (29.79% +/- 18.61%); BVC was (14.45 +/- 9.29) units; LVC was (2.73 +/- 4.57) units and PMN was (13.45 +/- 13.09) units. In 7 patients with IT more than 64 months (accounted for 32% of 22 cases), lymphangiogenesis [(8.6 +/- 3.8) units] and hemangiogenesis [(22.3 +/- 11.1) units] were both present. In these 7 patients, the whole number of LVC was 60 units, constituting 16% of all vessels (BVC+LVC = 378 units). The correlation coefficient of LVC with IT, ID, BVA, PMN and II was -0.673, 0.604, 0.755, 0.806 and 0.873, respectively. P value of all these correlations was less than 0.05. Further regression analysis revealed that LVC could be approximately calculated from II and BVA multiplying certain constant coefficients separately (resulting in lymphatic index, LI). Lymphatic vessels with characteristic ultrastructures and inflammatory cells were identified by transmission electronic microscopy. CONCLUSIONS: Lymphatic vessels exist in part of alkali burned human corneas and may be estimated through II and BVA indirectly. Lymphatic index may be a convenient and useful clinical index for evaluating lymphangiogenesis in corneal alkali burn.

[Slit lamp optical coherence tomography study of anterior segment changes after phacoemulsification and foldable intraocular lens implantation].

OBJECTIVE: To investigate quantitative changes of the anterior segment configuration after clear corneal incision phacoemulsification and foldable intraocular lens (IOL) implantation with slit-lamp-adapted optical coherence tomography (SL-OCT). METHODS: In prospective consecutive case series, clear corneal incision phacoemulsification and foldable intraocular lens implantation were performed in 44 eyes of 40 patients. The changes of the anterior segment configuration were performed by SL-OCT before and 1 day, 1 week, 2 weeks and 1 month after surgery. SPSS 16.0 software was used to analyze statistical difference. RESULTS: For all patients, the central corneal thickness (CCT) and the incisional corneal thickness (ICT) increased significantly 1 day after surgery (CCT increased 99.59 microm, ICT increased 234.57 microm; P = 0.490). At 1 month, the CCT almost had returned to baseline, but the ICT had been thicker about 19.25 microm than baseline(P = 0.001). The measurements of ACD, AOD500, AOD750, TISA500, TISA750 also increased significantly 1 day after surgery. Although the ACD had no changes within 2 weeks (all P < 0.05), it had been not stable. The changes of the width of the anterior chamber had been stable in the early period after surgery (all P > 0.05). CONCLUSION: The SL-OCT could impersonality and quantificationally evaluate the anterior segment changes induced by cataract surgery.