Volume 49 · Issue 02 · 2013

To avoid data bias in clinical research,it is essential to carefully select the suitable analysis of statistics on different research purposes and designs.It is optimal that team-work by statistician,scientist and specialist will assure to obtain reliable and scientific analysis of a study.The best way to analyze a study is to select more appropriate statistical methods rather than complicated ones. (Chin J Ophthalmol,2013,49:100-101)

To evaluate the efficacy and complication of glaucoma drainage implant surgery with scleral graft,scleral flap and artificial biological dural graft as the tube coverage.

Thirty-five cases (35 eyes) with refractory glaucoma who underwent FP-7 Ahmed glaucoma drainage implantation from January 2009 to June 2011 were retrospectively studied.Kaplan-Meier survival curve was applied to analyze the probability of success rate of three different tube coverage,the log-rank test used to compare the difference between tubes,and Cox proportional hazards regression analysis performed to predict the risk factors for failure.

Conjunctival shrink back leading to exposure of tube coverage occurred in 6 eyes in artificial biological dural graft group.Intraocular pressure (IOP) elevation by encapsulated cystic blebs around the plate was seen in scleral flap group (2 eyes) and scleral graft group (1 eyes),respectively.The drainage tube exposure occurred in 1 eye in scleral graft group.Kaplan-Meier survival curve analysis showed that the success rate was 8/10,3/9 and 14/16 in scleral graft group,artificial biological dural graft group and scleral flap group,respectively,at 12 month and 15 month.There was a significant difference among three groups (P=0.009).The proportional hazards regression showed that artificial biological dural graft was statistically significant risk factors for failure (HR=10.844,P=0.015).Compared with preoperation,the post-operative mean IOP was significantly decreased in all three groups.Postoperative IOP was not significantly different among three groups in different follow-up time point (F=0.028-1.218,P>0.05).

Both of scleral flap group and scleral graft group are comparable in the efficacy and complication of glaucoma drainage implant surgery and have a high success rate.However,artificial biological dural graft has poor compatibility with conjunctiva resulting in severe complications,which is not recommended to be used in glaucoma drainage implant surgery. (Chin J Ophthalmol,2013,49:102-108)

To quantitatively measure and evaluate the ocularanterior segment parameters in different subtypes of primary angle-closure glaucoma (PACG) using anterior segment optical coherence tomography (AS-OCT).

This retrospective study collected Fifty-five subjects (55 eyes) with APACG,63 (63 eyes) with chronic primary angle-closure glaucoma (CPACG) and 90 (90 eyes) normal controls from December 2009 to December 2010 in Zhongshan Ophthalmic Center.AS-OCT examinationwas performed on all patients and the anterior segment parameters were recorded including:central anterior chamber depth (ACD),anterior chamber width (ACW),anterior chamber volume (ACV),angle opening distance (AOD),trabecular iris area (TISA),angle recess area (ARA),lens thickness (LT) and crystalline lens rise (CLR).The differences of parameters between APACG,CPACG and normal controls were compared.

The anterior segment parameters of APACG and CPACG were significantly (P≤0.001) smaller,respectively,than those of normal controls (PACG: ACD 1.81±0.25 mm,ACW 11.30±0.43 mm,AOD 0.039 mm,ARA 0.038 mm²,ACV 72.8±16.04 mm³,TISA 0.017 mm²,Mean±SD,and CPACG: ACD 2.02±0.25,ACW 11.49±0.45,AOD 0.042,ARA 0.053,ACV 83.60±19.49,TISA 0.022 vs.normal: ACD 2.70±0.35,ACW 11.81±0.47,AOD 0.260,ARA 0.197,ACV 148.52±31.89,TISA 0.100).The LT and CLR of PACG were significantly (P<0.001) larger,respectively,than that of normal controls (LT: APACG 5.22±0.38,CPACG 5.06±0.36 mm,CLR: APACG 1.07±0.26,CPACG 0.94±0.21 mm vs.normal: LT 4.57±0.42,CLR 0.39±0.33 mm).Compared with CPACG,the anterior segment parameters of APACG were significantly (P<0.001—0.015) decreased,but the LT (P=0.003) and CLR were significantly (P<0.001) increased.Compared with APACG-fellow eyes,the anterior segment parameters of APACG-attacked eyes were significantly (P<0.001-0.041) decreased (Fellow-eye: ACD 1.90±0.23 mm,AOD 0.045 mm,TISA 0.037 mm²,ARA 0.047 mm2 vs.attached-eye: ACD 1.81±0.25,AOD 0.039,TISA 0.017 and ARA 0.038),while CLR was significantly (t=1.349,P=0.043) increased (fellow-eye:1.01±0.23 mm vs.Attached-eye:1.07±0.26).There was no significant difference in the other AS-OCT parameters between APACG-attacked eyes and fellow eyes (t=0.574-1.147,P=0.257-0.567).

Our results indicated a more crowding anterior segment configurationin PACG than that in normal controls and a more anterior located and thicker lensin APACG than that in CPACG,which constitute a morphological basis of acute attack. (Chin J Ophthalmol,2013,49:109-115)

To compare peripapillary choroidal thickness (CT) between primary open angle glaucoma (POAG) and normal subjects using enhanced depth imaging optical coherence tomography (EDI-OCT).

This research was a cross-sectional study.A 360-degree 3.4 mm diameter peripapillary circle scan was performed for retinal nerve fiber layer (RNFL) assessment by EDI-OCT in one eye of 40 POAG patients and 41 age-and sex-matched normal subjects.The observer used the manual segmentation function to delineate the posterior edge of the retinal pigment epithelium and the sclerochoroidal interface.The RNFL thickness algorithm function was used to automatically generate the CT in corresponding sectors.The intra-and inter-observer reproducibility was evaluated by intraclass correlation coefficient (ICC).Repeated measures ANOVA and LSD-t test were used to analyze differences in CT by peripapillary location.A Pearson correlation was calculated for variation in CT relative to age and RNFL.Spearman rank correlation was calculated to test the strength of the relationship between global mean RNFL and visual field mean deviation (MD) and between CT and MD.Independent-samples t-test was conducted to compare mean RNFL and CT between POAG and normal subjects.

The intra-and interobserver ICC values ranged from 0.993 to 0.999 and 0.993 to 0.998 respectively.In both groups,the CT showed a negative correlation with age at each peripapillary location (r=-0.509 to-0.608,-0.549 to-0.668;P=0.000 to 0.001) but no significant correlation with RNFL for any location (r=-0.186 to 0.273,-0.090 to 0.132;P=0.092 to 0.869).The peripapillary CT was thickest superotemporally and superonasally,then nasally and temporally,and was thinnest inferotemporally and inferonasally (P=0.000 to 0.036).Compared to normal subjects,eyes with POAG had significantly thinner RNFL at all locations (t=6.975 to 16.087,P=0.000),but CT measurements did not differ between groups for any location (t=-0.474 to 0.367,P=0.637 to 0.978).In POAG patients,the global mean RNFL (r_s=-0.511,P=0.001) but not CT (r_s=-0.285,P=0.079) was found to significantly correlate with visual field MD.

The peripapillary CT in POAG neither differ from that in normal subjects nor correlate with RNFL and visual field index,which does not support using it as a clinical parameter in glaucoma diagnosis or management. (Chin J Ophthalmol,2013,49:116-121)

To explore the risk factors of primary open angle glaucoma (POAG) in women.

This retrospective,case-control study collected 128 female patients with POAG and 142 female with normal controls without POAG from 2009 to 2010.The risk factors including family history,hypertension,diabetes,age of menarche,age of menopause,parity,oral contraceptive (OC) use,hormone therapy were analyzed by logistic regression analysis.

Compared with normal control group using logistic regression analysis,there were significant differences in such risk factors in POAG group as family history (OR=43.36,95%CI:5.69—346.67;P<0.001),hypertension (OR=3.29,95%CI:1.82—5.94;P<0.001),age of menarche (OR=2.046,95%CI: 1.17—3.54;P=0.011),age of menopause (OR=0.57,95%CI:0.32—0.99;P=0.049),hormone therapy (OR=0.29,95%CI:0.09—0.92;P=0.036).

Family history and hypertension are high risk factors to develop POAG for women.However,female hormones may play a protective role in women with POAG. (Chin J Ophthalmol,2013,49:122-125)

To study the clinical characteristics and pathogenesis of malignant glaucoma in a 5-year retrospective analysis in Zhongshan Ophthalmic Center (ZOC).

Medical records of 5-year malignant glaucoma patients in Zhongshan Ophthalmic Center were reviewed retrospectively.Patients'age,gender,original disease,duration before attack,axial length and the change of depth of anterior chamber,intraocular pressure and visual acuity before and after therapy and at final follow-up were checked and analyzed.

One hundred and eighteen cases of malignant glaucoma were hospitalized in ZOC from April 2005 to March 2010,accounts for 2.17% of PACG patients.Average age of malignant glaucoma patients was lower than that of PACG patients.The mean axial length of malignant glaucoma patients was shorter than that of Chinese population.Malignant glaucoma attacked between 1 day and 4.5 years after surgery.Ninty-three percent patients required medication and surgeries.Lens extraction and anterior vitrectomy were more effective than anterior chamber reforming combined with vitreous aspiration.The mean age of failed patient with vitreous cavity suction combined with anterior chamber angioplasty surgery was (43.7±4.8) years,and was significantly younger than succeed patients,(53.7±12.6) years (P<0.05).

Malignant glaucoma are iatrogenic and nine tenths secondary to surgeries of PACG patients.Topical application of atropine is the first choice of medication.Lens extraction combined with anterior vitrectomy has more privileges,however,is not commended especially for younger patients. (Chin J Ophthalmol,2013,49:126-129)

To know the difference of measured anterior chamber depth (ACD) in cataract eyes between A-scan and ultrasound biomicroscopy (UBM) measurements.

Case series study,the ACD of 396 patients (480 eyes with cataract) came from the Department of Ophthalmology,Nanjing Drum Tower Hospital between January,2008 and March,2010,were measured by A-scan and UBM.Two groups were classified by whether the optical area of anterior cortex was transparent or not:433 (90.21%) eyes with transparent anterior cortex and 47 (9.79%) eyes with opacific anterior cortex.The former are classified into 3 groups:﹤3.0 mm,3.0-3.5 mm,﹥3.5 mm,according to the ACD value of UBM.The differences of ACD between A-scan and USB readings was analyzed.

The average ACD value of cataract eyes with transparent anterior cortex was (3.24±0.56) mm (measured by USB) and (3.14±0.56) mm (measured by Ascan),respectively.There was no significant difference between these two measurements (t=0.128,P=0.082).In eyes with ACD<3.0 mm,the average ACD was (2.61±0.26) mm (by UBM) and (2.50±0.29) mm (by A-scan),respectively,with a difference of (0.11±0.10) mm.There was a statistical significant difference between these two measurements (t=0.744,P=0.023).The average ACD value of cataract eyes with opacific anterior cortex opacity was (2.51±0.52) mm (by UBM) and (3.84±0.55) mm (by A-scan),respectively,with a difference of (-1.33±0.41) mm.There was a significant difference between these two values (t=14.792,P=0.000).

In cataract eyes with transparent optic area of anterior cortex,there is no significant difference between measured ACD by Ascan and UBM.In eyes with ACD less than 3.0 mm,there is a significant difference between measured value by A-scan and UBM.When the optical area of anterior cortex is opacific,A-scan records are much higher than the ACD value measured by UBM. (Chin J Ophthalmol,2013,49:130-133)

To observe the rate of secondary glaucoma after pediatric congenital cataract surgery in the first 36 months of life.

Retrospective case series.The records of children who underwent surgery for congenital cataract within the first 36 months of life between July 1995 and July 2005 at Qingdao Eye Hospital were reviewed.Children with preoperative conditions associated with glaucoma were excluded.Age at surgery,unilateral or bilateral cataract,type of congenital cataract,primary intraocular lens (IOL) insertion,duration of follow-up,postoperative best corrected visual acuity,development of aphakic glaucoma,and development of glaucoma after secondary IOL implantation were evaluated.

A total of 115 patients (204 eyes) with an average surgery age of (12.5±9.2) months were included; the mean follow-up time was (83.7±43.8) months.15 eyes (11 patients) (7.4%) had subsequent development of glaucoma,7 of which (4 patients) developed late-onset open-angle glaucoma.Of the 15 eyes,13 eyes had surgery within 9 months,and 12 eyes developed nuclear or total cataract.None of the primarily pseudophakia eyes developed glaucoma in our study.Of 86 eyes that received implantation of secondary intraocular lens in the ciliary sulcus,13 eyes (15.1%) developed pseudophakia glaucoma.

Secondary glaucoma occurred after pediatric bilateral cataract surgery.As late-onset glaucoma usually occurred several years after primary surgery,long-time follow-up after pediatric cataract surgery needs to be emphasized. (Chin J Ophthalmol,2013,49:134-138)

To compare the clinical performances of patients in different ages with implantation of a accommodating IOLs.

It was a retrospective study.Forty-seven eyes (47 patients) were enrolled in 3 groups for phacoemulsification and a accommodating IOL implantation.According to their ages,they were divided into 3 groups:≤45 years,46—59 years,and≥60 years.Parameters analyzed after more than 3 months postoperation were uncorrected distance,best-corrected distance,uncorrected near,and distance-corrected near visual acuities; changes of anterior chamber depth (ACD) during accommodative measured using the ultrasound biomicroscopy (UBM) ;changes of ACD by instilling 2% pilocarpine using the A-ultrasonic scan; and the amplitude of accommodation using the pushing-up test.

No significant difference was observed between distance and near visual acuities of IOL groups.The mean changes of ACD measured with UBM in the group of≤45 years[ (0.16±0.12) mm] was significantly higher than the other age groups[46—59 years,(0.06±0.06) mm,P=0.00;≥60 years,(0.07±0.05) mm,P=0.008) ].The mean changes of ACD stimulated by pilocarpine measured with A-ultrasonic scan in the group of≥60 years[ (0.17±0.14) mm] was significantly lower than the other age groups[≤45 years,(0.68±0.44) mm,P=0.00;46—59 years,(0.43±0.20) mm,P=0.00].The accommodative amplitude of the≥60 years groups ( (2.32±0.88) D) was lower than the group of≤45 years[ (2.87±0.52) D,P=0.005].

The accommodative amplitude of patients implanted with accommodating IOLs stepped down following the increase of age.However,no statistical differences were found in distance and near visual acuities between the different age groups. (Chin J Ophthalmol,2013,49:139-143)

To investigate the etiological spectrum of moderate to severe visual impairment and blindness in population aged 50 years or more in rural Shandong province,China.

A population based,random cluster sampling was used to screening the adults aged 50 years or more living in rural Shandong Province from April to July 2008.Three counties and one suburb representing the different levels of socioeconomic development within Shandong area were selected as the investigated areas.Geographically defined cluster sampling was used in randomly selecting a crosssection of residents aged≥50 years from each county.Best corrected visual acuity and intra-ocular pressure were evaluated in those with presenting visual acuity≤0.5 and suspected glaucoma respectively.The major causes of visual impairment and blindness were diagnosed in those with presenting visual acuity≤0.3.According to the results of presenting visual acuity and best corrected visual acuity,the etiology constituent ratios of the moderate to severe visual impairment and blindness were analyzed respectively.

According to the number of people,the first three principal causes for blindness based on the presenting visual acuity were cataract (59.8%,168/281),fundus disease (12.1%,34/281) and corneal opacity (4.3%,12/281) or ametropia (4.3%,12/281).The first three principal causes for moderate to severe visual impairment and blindness were cataract (55.2%,844/1530),uncorected refractive error (18.2%,278/1530) and fundus disease (11.9%,182/1530).Based on the best corrected visual acuity,the first three principal causes for blindness were cataract (64.6%,153/237),fundus disease (10.5%,25/237) and corneal opacity (4.7%,11/237),respectively.The first three principal causes for moderate to severe visual impairment and blindness were cataract (66.4%,590/889),fundus disease (16.0%,142/889) and optic nerve atrophy (3.0%,27/889).According to number of the eyes,proportion of cataract in cases with moderate to severe visual impairment and blindness had positive relation with age,the proportion of ametropia and fundus disease had negative relation with age.The etiology constituent ratio had no difference between male and female.The proportion of cataract in cases with moderate to severe visual impairment and blindness in Huaiyin District of Jinan was slightly lower than those in other areas,however,the proportion ratio of ametropia and fundus disease was slightly higher than those in other areas.

Cataract,uncorected refractive error,and fundus diseases are ranked in the top three causes of moderate to severe visual impairment and blindness in adults aged 50 years or more in rural Shandong Province. (Chin J Ophthalmol,2013,49:144-150)

To evaluate the efficacy of silicone punctual plug for treating aqueous tear deficiency dry eye patients.

Prospective consecutive cases study.Silicone punctal plugs (France Chirurgie Instrumentation) were inserted into lower canaliculus in 65 tear deficiency dry eye patients (65 eyes).The clinical data collected included sex and age of the patients,frequency of lubricant use,the Ocular Surface Disease Index (OSDI) scores,slit lamp microscope examination,Schirmer I test (SIT) (with anesthesia),tear break-up time (TBUT),and ocular surface staining with fluoresce in sodium.All examinations were recorded at baseline,6 weeks and 6 months after punctal occlusion.

There were 41 women and 24 men in this study,and their average age was 41.77 years old.The dry eye symptoms improved in 57 (87.69%) of 65 eyes at 6 months follow-up.The frequency of lubricant use was significantly decreased in these eyes (χ²=81.97,P<0.01).More importantly,the symptoms disappeared in 25 (38.46%) eyes,which did not need lubricant any more.At baseline,6 weeks and 6 months after punctal occlusion,OSDI mean score was 37.32±2.41,19.60±8.07 and 18.17±7.93,respectively (F=344.10,P<0.01) ; mean SIT result was (3.03±0.75) mm,(6.66±2.10) mm and (6.75±2.16) mm,respectively (F=169.59,P<0.01) ; mean TBUT was (2.91±0.76) s,(7.02±2.39) s and (7.57±2.38) s,respectively (F=242.00,P<0.01).Compared with the baseline data,hyperemia of conjunctiva grading and ocular surface staining scores were also improved significantly after plug insertion,and all of these differences were statistically significant.Foreign body sensation was the most common complication in our study (12 eyes,18.46%).Epiphora (4 eyes,6.15%),partial extrusion (3 eyes,4.62%),and total extrusion (3 eyes,4.62%) were the other complications encountered.

Silicone punctal plug insertion is a stable,effective and safety method for the treatment of tear deficiency dry eye. (Chin JOphthalmol,2013,49:151-154)

Glaucoma is an eye disease that can lead to irreversible visual impairment.Trabeculectomy remains the most common operation for glaucoma therapy.The formation of functional filtering bleb is the key to the success of surgery.But many studies have found that antiglaucoma surgeries affected the normal function of the tear film,which can cause the change of the structure of ocular surface resulting in an uncomfortable feeling and dry eye.Most investigators have suggested that the alteration of ocular surface by trebulectomy is due partially to the damage of ocular surface tissues and topical application of the drugs of antimetabolism as well as the lack of vascular supply of ultra-thin post-operative filtering bleb. (Chin J Ophthalmol,2013,49:185-188)

UVA-riboflavin cross-linking is an effective approach to increase the mechanical and biochemical rigidity of the collagen fiber,which has been used in treating some corneal diseases such as keratoconus,and might become a new treatment modality for strengthening scleral tissue to prevent progressive myopia,so the safety of the new therapy has be paid attention widely.This article focus on the diffusion process and saturation judgment of riboflavin and describes the effect of riboflavin,direct UV damage,photochemical damage and the prevention of side effects in cross-linking therapy. (Chin J Ophthalmol,2013,49:189-192)

Anti-glaucoma surgery is one of important methods for glaucoma therapy.It is easy to perform a glaucoma surgery.However,it is not easy to perform a successful one.The management of peri-operation will provide a path for success of glaucoma surgery.The management of perioperation includes a well preparation of pre-operation and a following-up care of post-operation,which requires a systemical and topical evaluation of patients in pre-operation based on the mechanism of IOP elevation to determine indications,a suitable surgical design,preventive measure for complications during the operation,and a skillful surgical technique.Finally,Careful follow-up of post-operation will guarantee a successful anti-glaucoma surgery and achieve the expectation of both physicians and patients. (Chin J Ophthalmol,2013,49:97-99)