Multi-level ranking classification algorithm for nuclear cataract based on AS-OCT image / 中华实验眼科杂志

Objective:To investigate the diagnostic value of an intelligent assisted grading algorithm for nuclear cataract using anterior segment optical coherence tomography (AS-OCT) images.Methods:A diagnostic test study was conducted.AS-OCT image data were collected from 939 cases of 1 608 eyes of nuclear cataract patients at the Shanghai Tenth People's Hospital of Tongji University from November 2020 to September 2021.The data were obtained from the electronic case system and met the requirements for clinical reading clarity.Among them, there were 398 cases of 664 male eyes and 541 cases of 944 female eyes.The ages of the patients ranged from 18 to 94 years, with a mean age of (65.7±18.6) years.The AS-OCT images were labelled manually from one to six levels according to the Lens Opacities Classification System Ⅲ (LOCS Ⅲ grading system) by three experienced clinicians.This study proposed a global-local cataract grading algorithm based on multi-level ranking, which contains five basic binary classification global local network (GL-Net).Each GL-Net aggregates multi-scale information, including the cataract nucleus region and original image, for nuclear cataract grading.Based on ablation test and model comparison test, the model's performance was evaluated using accuracy, precision, sensitivity, F1 and Kappa, and all results were cross-validated by five-fold.This study adhered to the Declaration of Helsinjki and was approrved by Shanghai Tenth People's Hospital of Tongji University (No.21K216).Results:The model achieved the results with an accuracy of 87.81%, precision of 88.88%, sensitivity of 88.33%, F1 of 88.51%, and Kappa of 85.22% on the cataract dataset.The ablation experiments demonstrated that ResNet18 combining local and global features for multi-level ranking classification improved the accuracy, recall, specificity, F1, and Kappa metrics.Compared with ResNet34, VGG16, Ranking-CNN, MRF-Net models, the performance index of this model were improved.Conclusions:The deep learning-based AS-OCT nuclear cataract image multi-level ranking classification algorithm demonstrates high accuracy in grading cataracts.This algorithm may help ophthalmologists in improving the diagnostic accuracy and efficiency of nuclear cataract.

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.

Anterior segment optical coherence tomography characteristics and management of a unique spectrum of foreign bodies in the cornea and anterior chamber

Purpose: To report anterior?segment optical coherence tomography (ASOCT) characteristics of different types of corneal and anterior chamber (AC) foreign bodies (FBs) and their usefulness in diagnosis and management. Methods: This is a retrospective descriptive clinical study involving 11 eyes of 11 patients who presented at the outpatient department of a tertiary ophthalmic care center from January 2017 to January 2022. All patients had a diagnosed or suspected corneal FB. All participants underwent a comprehensive ophthalmological examination, followed by slit?lamp photography and ASOCT. FB removal was done where required by an external, internal, or combined approach. Results: The mean age of patients was 28.2 (7–53) years. Ten were male, and one was female. Seven patients had a definitive positive history of injury; in one, there was a history suggestive of trauma, one had the post?operative complication of scleral buckling surgery, and two patients had a history of insect fall in the eyes. Three patients had acute, four had sub?acute, and four had chronic presentations. Descemet’s membrane (DM) breach was suspected in three cases of deep FB, which was later confirmed on ASOCT. In two cases, DM was presumed to be intact clinically, but ASOCT showed an AC penetration. The FB was removed in seven patients, one via slit?lamp, one via an external approach, two via an internal approach, and three via a combined approach. Conclusion: ASOCT facilitates non?invasive rapid imaging of ocular tissue at various depths, provides an accurate assessment of FB characteristics, and thereby serves as an additional tool in our armamentarium for diagnosis and management of deep corneal and AC Fbs

Architectural analysis of subconjunctival oblique limbus incision techniques in manual cataract extraction surgery by optical coherence tomography imaging

The purpose was to assess the profile of subconjunctival oblique limbus incision (SCOLI) design by using anterior-segment optical coherence tomography (AS-OCT) and try to emphasize the proper technique of wound construction. The structural dimensions and integrity of the wound were acquired from the patients, who had undergone manual small-incision cataract surgery with SCOLI techniques, using a Canon OCT anterior-segment imaging system on the first postoperative day. The use of AS-OCT allowed for an in vivo evaluation of SCOLI in high definition. The radial OCT scan image showed three staggered incisions, including conjunctiva incision, scleral entrance, and inner corneal lip. A tangential scan demonstrated that the internal lip is parallel to the curvature of the peripheral cornea. The en face image showed an asymmetric 4 arc-shaped configuration rather than a symmetrical one. In conclusion, AS-OCT could be used to analyze SCOLI to determine optimal wound construction and geometry. The results of this study indicated that an asymmetric 4 arc-shaped limbus tunnel incision was superior to the conventional linear equivalent in stability and nucleus delivery.

Posterior corneal morphological changes in primary congenital glaucoma

Purpose: To compare posterior corneal morphology between older treated and younger untreated children with primary congenital glaucoma (PCG) using anterior segment optical coherence tomography (ASOCT) and intraoperative OCT (iOCT), respectively. Methods: In this comparative study, ASOCT of older PCG children were compared with iOCT of younger untreated PCG patients. Differences between the two groups with respect to posterior corneal morphology were studied. Results: Observed morphological patterns within posterior cornea in older treated (age: 72–300 months) children (87 eyes) included Descemet’s membrane (DM) excrescences (70%), thickened DM (35%), intracameral twin protuberances (92%), and DM detachment (26%). Changes within pre?Descemet’s layer (PDL) (28%) included thickening, breaks, and detachments. Extent of Haab’s striae was associated with thickness of DM/PDL complex (P = 0.008) when analyzed in the treated group. In contrast, in the untreated group (n = 53 eyes, age 1–63 months), posterior corneal changes were limited to diffuse hyper?reflectivity of the DM/PDL complex, with absence of DM tears. Conclusion: Posterior cornea thickens and Haab’s striae become more circumscribed in eyes of older treated children compared to untreated PCG eyes, probably reflecting a healing response of posterior cornea over time.

Reticular epithelial corneal edema as a novel side-effect of Rho Kinase Inhibitors: An Indian scenario

Purpose: To describe clinical course, characteristics, and outcome of reticular epithelial corneal edema (RECE) occurring as a not?so?infrequent adverse effect of a novel drug, Rho?kinase inhibitors (ROCK?I)? netarsudil (0.02%) and ripasudil (0.4%). Methods: This was a retrospective observational non?randomized study. In this study, 12 eyes of 11 patients presenting at a tertiary eye care center between April 2021 and September 2021 were included. All 12 eyes developed a distinctive honeycomb pattern of RECE after starting topical ROCK?I. All patients were subjected to detailed ophthalmic examinations. Results: Eight patients were started on netarsudil (0.02%) and three on ripasudil (0.4%). Five eyes had a prior history of corneal edema. The remaining seven had the presence of ocular comorbidities predisposing to corneal edema. The average time for RECE occurrence was 25 days for netarsudil and 82 days for ripasudil. Visual acuity decreased in two eyes, remained unaffected in four eyes, and could not be quantified in four eyes due to preexisting profound visual impairment. Five eyes had symptoms of ocular surface discomfort associated with bullae. Symptoms and bullae resolved in all eyes in whom ROCK?I was stopped. The average time to resolution of RECE was 10 days for netarsudil and 25 days for ripasudil. Conclusion: RECE after ROCK?I occurs with the use of both netarsudil and ripasudil, although the characteristics differ. The presence of corneal edema and endothelial decompensation seem to be a risk factor, and cautious use is warranted in these patients. Four clinical stages of RECE are described. ROCK?I act as a double?edged sword in patients with endothelial decompensation. Large?scale studies are required to know the exact incidence, pathophysiology, and long?term consequences of the aforementioned side?effect.

Comparison of anterior chamber angle parameters and iris structure of juvenile open-angle glaucoma and pigmentary glaucoma

Purpose: To compare the quantitative measurements of the anterior chamber angle (ACA) and iris parameters in patients with juvenile open?angle glaucoma (JOAG), pigmentary glaucoma (PG), and healthy controls using anterior segment optical coherence tomography (AS?OCT). Methods: This was a retrospective, cross?sectional study of 25 eyes with JOAG, 25 eyes with PG, and 25 control eyes. Anterior chamber depth, angle?opening distance 500 and 750, trabecular–iris space 500 and 750, scleral spur angle, iris thickness (IT, measured at the thickest part), and iris bowing were obtained using AS?OCT (Visante” OCT 3.0 Model 1000, Carl Zeiss Meditec, Inc). Results: The quantitative ACA parameters were found to be significantly higher in JOAG and PG patients compared to healthy controls (P < 0.001); there was no significant difference between the eyes with JOAG and PG (P > 0.05). In eyes with JOAG and PG, there was significantly backward bowing of the iris in temporal and nasal angles compared to control subjects (P < 0.001). Median iris bowing was not significantly different between the patients with JOAG and PG (P > 0.05). The temporal and nasal angle iris thickness were significantly thinner in eyes with JOAG than the eyes with PG (P < 0.001) and age?matched control subjects (P < 0.001). The median IT did not differ between the patients with PG and control subjects (P > 0.05). In patients with JOAG, the intraocular pressure (IOP) was inversely correlated with IT (r = ?0.43, P < 0.05). Conclusion: AS?OCT provided quantitative data on the ACA and iris parameters in JOAG and PG. The evaluation of the ACA and iris structures using AS?OCT revealed higher ACA measurements and posterior bowing of the iris in patients with JOAG and PG. Furthermore, the patients with JOAG were found to have thinner IT than the ones with PG and healthy controls

Effect of the inside mouth positions of clear corneal incisions of cataract on astigmatism after surgery was analysised using anterior segment optical coherence tomography / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the influencing factors of clear corneal incision(CCI)after phacoemulsification by Logistic regression analysis. <p>METHODS: A retrospective cases-control study was performed. 126 patients(138 eyes)who received phacoemulsification combined with implantation of foldable intraocular lens(IOL)were included in Erdos Central Hospital. Postoperative 1d, all of the CCIs were scanned by anterior segment optical coherence tomography(AS-OCT). According to whether there were presence of inner opening CCIs, the patients were divided into two groups. Group 1: inner opening CCIs(84 eyes)were absent. They were stable. Group 2: inner opening CCIs(54 eyes)were present. The factors affecting the stability of CCI were analyzed.<p>RESULT: The incidence of internal opening incisions was 39.1%(54/138). It decreased to 8.7%(12/138)at 1wk. One month postoperative, the internal mouths of the incisions were completely closed. The stability of the incisions was good. But AS-OCT scan found 3 cases with poor healing internal incisions. Binary Logistic regression analysis showed that age, incision length, incision angle, location of the internal incision, incision method and descemet's membrane detachment had statistically significant difference(<i>OR</i>=1.102, 0.994, 27.895, 0.127, 30.269, 6.750, all <i>P</i><0.05).<p>CONCLUSION:Age, incision length, incision angle, location of the internal incision, incision method and descemet's membrane detachment are the influencing factors of CCI stability after phacoemulsification.

Observation of intraocular lens and posterior capsular attachment after high myopia cataract operation by new generation of AS-OCT / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To quantify and evaluate the capsular adhesion to intraocular lens(IOL)in subjects with high myopia by the latest anterior segment optical coherence tomography(AS-OCT).<p>METHODS: Retrospective case observation study was designed. Sixty eyes of 60 patients who received extra-capsular extraction combined with IOL implantation in Shenzhen Eye Hospital from October 2019 to December 2019 were divided into two groups by axial length(AL), of which 30 eyes were highly myopic(AL>26mm)and 30 eyes were emmetropic(22mm<AL<24.5mm). All eyes were examinated by AS-OCT at 1, 7, and 30d after operation. The area between IOL and posterior capsule(AREAP)and residual side length of posterior capsule not adhesion were evaluated. Kaplan-Meier survival analyses of attachment rates were studied. The ratios of posterior capsule attached IOL of the two groups at different postoperative times were compared by Log-Rank.<p>RESULTS: In the emmetropic group, the AREAP was(0.81±0.37),(0.33±0.19)and(0.14±0.06)mm² at 1, 7, and 30d after operation, respectively. The residual side lengths of posterior capsule not adhesion were(7.93±3.03),(3.95±2.44)and(1.26±0.08)mm. The ratios of posterior capsule attached to IOL were 33%, 67% and 83%. In the highly myopic group, the AREAP were(3.29±0.43),(1.54±0.66)and(0.62±0.28)mm² at 1, 7, and 30d postoperatively, respectively. The residual side lengths of posterior capsule not adhesion were(13.56±4.02),(8.13±3.90)and(3.78±2.51)mm. The ratios of posterior capsule attached to IOL were 0, 7% and 23%. There were statistically significant differences between the two groups in AREAP, residual side lengths of posterior capsule not adhesion and the ratios of posterior capsule attached to IOL(<i>P<</i>0.05).<p>CONCLUSION: There is more space between posterior capsule and IOL after cataract surgery in highly myopic patients. The new generation of AS-OCT can clearly display the image of the posterior capsule of the lens, which is expected to be an effective examination device for the study of lens-related diseases.

Correlation of iris collagen and in-vivo anterior segment structures in patients in different stages of chronic primary angle-closure in both eyes

Purpose: To compare the density of iris collagen and anterior segment parameters in eyes with chronic primary angle closure glaucoma (CPACG) and their fellow eyes with confirmed or suspected primary angle closure (PAC/PACS). Methods: Nineteen patients with CPACG in one eye and PAC/PACS in the fellow eye requiring trabeculectomy in the CPACG eye and iridectomy in the fellow eye were recruited. Anterior segment optical coherence tomography (AS-OCT) measurements were conducted under light and dark conditions. Iris specimens, obtained by iridectomy/trabeculectomy, were analyzed by sirius red polarization for quantifying type I/III collagen density. AS-OCT parameters and type I/III collagen densities were compared between the two eyes. Results: The iris curvatures were flatter in CPACG eyes in light and dark conditions (P < 0.05). The iris areas in light condition and iris thicknesses in dark condition were smaller in CPACG eyes (P < 0.05). The density of collagen type I in CPACG eyes was lower (P = 0.048). The light-to-dark changes in CPACG eyes and PAC/PACS eyes, respectively, were ?0.679 ± 0.701 and ?1.627 ± 0.802 mm for pupil diameters, and 0.069 ± 0.113 and 0.258 ± 0.157 mm2 for iris areas, which differed significantly (P < 0.001). With the decrease of type I collagen, anterior chamber width increased and iris areas decreased in dark condition. Conclusion: Dynamic changes in pupil diameter and iris areas differed significantly between CPACG eyes and their fellow PAC/PACS eyes. Decreased type I collagen density in iris tissue was associated with decreased iris area and increased anterior chamber width, which may contribute to disease progression.

Corneal staining during cataract surgery: Natural course, ASOCT features, and preventive measures

We report the natural course of the accidental injection of trypan blue into the corneal stroma while performing a routine cataract surgery by a resident during a training session. The corneal staining resolved with conservative medical treatment over 7 weeks. This case describes the anterior segment optical coherence tomography (ASOCT) features of corneal staining. It emphasizes on the relatively benign nature of this dye and the follow-up course. Causes that may be responsible for this untoward complication are highlighted with the necessary preventive measures that need to be taken care are also discussed.

Evaluation of anterior segment parameters with two anterior segment optical coherence tomography systems: Visante and Casia, in primary angle closure disease

Purpose: To determine the comparability of anterior chamber biometric measurements in primary angle closure disease (PACD) patients using two commercially available anterior segment optical coherence tomography machines (ASOCT): Visante and Casia. Methods: This was a cross-sectional observational study, which included clinically, diagnosed cases of PACD. Anterior segment biometric measurements were done using Casia and Visante ASOCT. Parameters studied were central corneal thickness (CCT), anterior chamber depth (ACD), nasal (N) and temporal (T) angle opening distance at 500 ?m (AOD500) and 750 ?m (AOD750), and N and T trabecular iris space area at 500 ?m (TISA500) and 750 ?m (TISA750). Results: Total 36 PACD patients (72 eyes) with average age of 59.48 ± 7.95 years were recruited, out of which 25 were females (69.44%) and 11 males (30.56%). The mean measurements of CCT, ACD, AOD500, and TISA on Casia and Visante machines were 522.5 ± 34.75 ?m and 539.55 ± 29.56 ?m (P = 0.00); ACD- 2.144 ± 0.38 mm and 2.133 ± 0.39 mm (P = 0.487); AOD500-0.27 ± 0.16 ?m and 0.21 ± 0.10 ?m (P = 0.04); and TISA500-0.100 ± 0.07 ?m and 0.063 ± 0.03 ?m (P = 0.00), respectively. A statistically significant difference was noted in CCT, N and T AOD, and TISA. A good corelation for ACD and CCT (ACD = 0.9816 and CCT = 0.772) only were noted between the two machines. The Bland-Altman plot analysis of different parameters between two machines has revealed good agreement of measurement of ACD and CCT but poor agreement for rest of the parameters. Conclusion: It is advisable not use the two machines interchangeably because of the wide limits of agreement and poor correlation of angle measurement values of Casia and Visante ASOCT.

Successful treatment of conjunctival lymphangiectasia accompanied by corneal dellen using a high-frequency radiowave electrosurgical device

A 62-year-old man presented with a 1-month history of right eye pain unresponsive to artificial tears and topical steroids. At presentation, bullous yellowish fluid collection was noted in the nasal conjunctiva. Corneal thinning and opacity were observed at the 3 o'clock position of the cornea. High-frequency radiowave ablation and biopsy were performed at the affected area. Conjunctival lymphangiectasia was confirmed by excisional biopsy. An improvement in the degree of corneal dellen and chemosis was evident 1 week after ablation. Use of a high-frequency radiowave electrosurgical device may be a simple and effective treatment option for symptomatic conjunctival lymphangiectasia.

In vivo confocal microscopy and anterior segment optical coherence tomography follow-up of cysteamine treatment in corneal cystinosis

A 36-year-old female presented initially with photophobia and visual deterioration. After examination and laboratory tests, patient was diagnosed with cystinosis. Cysteamine drops 4 × 1 drops/day was given as treatment for 1 year. During follow-up, in vivo confocal microscopy (IVCM) and anterior segment optical coherence tomography (AS-OCT) was performed. Photophobia was relieved and IVCM obtained the decrease in size and density of corneal crystals 1 year after. Depth of corneal crystals did not change but crystal density score reduced with cysteamine treatment.

Application of anterior segment optical coherence tomography in the measurement of the parameters of lower tear meniscus and central corneal thickness / 中华实验眼科杂志

Objective To evaluate the application of the lower tear meniscus parameters measured by anterior segment optical coherence tomography (AS-OCT) in dry eye diagnosis.Methods A prospective randomized clinical controlled study was conducted.One hundred and thirteen dry eye patients (226 eyes) and 206 healthy volunteers (410 eyes) were enrolled from May 2015 to October 2016 in Shanxi Eye Hospital.The lower tear meniscus height (LTMH),lower tear meniscus area (LTMA),lower tear meniscus depth (LTMD),the corneal epithelial thickness (CET) at central 6 mm and the corneal thickness at central 6 mm were measured by RTVue-XR.The measurement results of the two groups were compared and the ROC curve was drawn.The dry eye group and the control group were divided into four age groups:＞20-30 years old,＞30-40 years old,＞40-50 years old and ＞50-60 years old.The changes of the parameters of the tear crescent in different age groups were compared.The changes of the lower tear meniscus with age were analyzed by linear regression equation.This study was approved by the Ethics Committee of Shanxi Eye Hospital.All operations were performed in accordance with the Helsinki Declaration,and written informed consent was obtained from each subject prior to any medical examination.Results The values of LTMH,LTMD and LTMA in dry eye group were (216.08±67.26) μm,(116.50±29.13) μm,(0.012 9±0.006 7) mm2,respectively,which were lower than (333.71±50.38) μm,(139.56±28.76) μm,(0.026 6±0.007 4)mm2 in control group,with statistical significance between the two groups (all at P＜0.05).The CET values of each quadrant in the central area of 2 mm,2-5 mm and 5-6 mm in the dry eye group were significantly lower than those in the control group,with statistically significant differences between the two groups (all at P＜0.05).The corneal thickness of central 5-6 mm region,1/8 above the superior nasal quadrant in the central range of 2-5 mm and 1/8 above the superior quadrant was not statistically significant between the two group (all at P＞0.05);the corneal thickness values of the other quadrant in dry eye groups were lower than those in control group,the differences were statistically significant (all at P＜0.05).The cut-off values of LTMH,LTMD,LTMA,CET at central 2 mm and corneal thickness at central 2 mm were 269.83 μm,122.02 μm,0.023 2 mm2,54.16 μm,531.50 μm,respectively,the sensitivity were 85.4％,88.9％ 96.5％,77.0％,66.8％,respectively;the specificity were 91.7％,70.5％,75.1％,56.8％,59.8％,respectively.The values of LTMA,LTMH and LTMD in each age group of dry eye group were significantly lower than those of the control group (all at P＜0.05).Linear regression analysis showed that LTMH was decreased by 3.966 μm and LTMD was decreased by 2.381 μm along with the increase of 1 year age in the control group,while LTMH was decreased by 1.293 μm along with the increase of 1 year age in the dry eye group.Compared with the control group,the area of the lower tear crescent image in the dry eye group was reduced,the boundary line was blurred and the coherence was poor in varying degrees,and the turbidity of the tear was increased.Conclusions AS-0CT can objectively reflect the shape of the lower tear meniscus parameters,central CET and central corneal thickness changes.The LTMH and LTMD of normal people are decreased with the increase of age.LTMA and LTMH have high diagnostic efficacy for dry eye and are expected to become one of the important methods for dry eye screening.

Comparison of the thinnest corneal thickness measured by Sirius, Oculyzer, AS-OCT and A-mode ultrasonography in myopic patients / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM:To compare the difference, correlation and consistency of the thinnest corneal thickness(TCT)in myopic patients among Sirius, Oculyzer, anterior segment optical coherence tomography(AS-OCT)and A-mode ultrasound pachymetry, in order to provide a reference for clinical applications.<p>METHODS: TCT was measured in 81 patients(162 eyes)treated between March and April, 2016 using Sirius, Oculyzer, AS-OCT and A-mode ultrasound pachymetry before femtosecond LASIK, and then the values were statistically analyzed.<p>RESULTS: TCT measured by A-mode ultrasound pachymetry, Sirius, Oculyzerand AS-OCT were respectively(537.91±24.12)μm,(538.12±22.64)μm,(538.20±23.74)μm,(527.04±23.11)μm(<i>P</i><0.01). There was a significant difference in TCT measurements among the four measurements. The results of AS-OCT were significantly smaller than those of the other three methods. There was no statistical difference among A-mode ultrasound pachymetry, Sirius and Oculyzer.Pearson correlation coefficient of measured value by the four measurements were more than 0.9(<i>r</i>=0.920, 0.914, 0.951, 0.908, 0.929, 0.919, <i>P</i><0.001), which means there were highly correlation between each other. The 95% <i>CI</i> of the consistency interval of A-mode ultrasound pachymetry and Sirius, A-mode ultrasound pachymetry and Oculyzer, A-mode ultrasound pachymetry and AS-OCT were(-18.77-18.33)μm,(-19.79-19.19)μm,(-3.79-25.53)μm, respectively. The Bland-Altman Plots demonstrates relatively good consistency between A-mode ultrasound pachymetry and the other three methods.<p>CONCLUSION:The TCT measured by AS-OCT were thinner than that measured by A-mode ultrasound pachymetry. There were a high correlation and consistency of the thinnest corneal thickness in myopic patients among Sirius, Oculyzer, AS-OCT and A-mode ultrasound pachymetry. The TCT measured by the four measurements can be referenced but not replaced since the 95% of the consistency intervals were wide.

Comparison of Pentacam and AS-OCT in measuring ophthalmic anterior segment biological parameters / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To compare the difference of corneal curvature, astigmatism, central corneal thickness and anterior chamber depth between the Pentacam anterior segment analyzer and anterior segment optical coherence tomography(AS-OCT)in young myopic preoperative and senile cataract patients.<p>METHODS: Prospective clinical study.Totally 64 preoperative examinations(124 eyes)and 61 senile cataract patients(85 eyes)were selected. Pentacam and AS-OCT were used to measure the people's parameters of the ophthalmic anterior segment. Paired sample <i>t</i>-test was used to compare the differences of the two devices' measurement results of the two groups. The correlation of the obtained data was analyzed by Pearson correlation analysis. The consistency of the measurement results was analyzed by Bland-Altman plot analysis.<p>RESULTS: There were significant differences in measuring steep Keratometry(Ks), flat Keratometry(Kf)and mean Keratometry(Km)between the two devices of myopia(<i>P</i><0.001), but there was no statistically significant difference in the cataract group(<i>P</i>>0.05). The astigmatic parameters J₀, central corneal thickness(CCT), and anterior chamber depth(ACD)measured by the devices and there were statistically significant differences between the two devices(<i>P</i><0.05)while there was no significant difference in the measured astigmatic parameters J₄₅(<i>P</i>>0.05). The results of Ks, Kf, Km, J₀, J₄₅, CCT and ACD measured by the two devices in both groups were linearly related(<i>P</i><0.001). The Bland-Altman plot analyses showed that the two devices had comparable results for J₀, J₄₅, CCT and ACD. The consistency of Ks, Kf and Km measured by the myopia group was good, while the consistency of Ks, Kf and Km measured by the cataract group was poor.<p>CONCLUSION: Pentacam and AS-OCT measurements of the ophthalmic anterior segment are consistent with astigmatic parameters, CCT and ACD, and can be used interchangeably. The consistency of Ks, Kf and Km is affected by age related factors, and Pentacam is preferred.

Comparison of Laser In Situ Keratomileusis Flap Morphology and Predictability by WaveLight FS200 Femtosecond Laser and Moria Microkeratome: An Anterior Segment Optical Coherence Tomography Study

PURPOSE: To evaluate laser in situ keratomileusis (LASIK) flap thickness predictability and morphology by femtosecond (FS) laser and microkeratome (MK) using anterior segment optical coherence tomography. METHODS: Fifty-two candidates for the LASIK procedure were stratified into two groups: FS laser-assisted (Allegretto FS-200) and MK flap creation (Moria 2). Flap thickness was determined at five points. The side-cut angle was measured in three directions at the margin interface. LASIK flap assessment was performed one month postoperatively by Spectralis anterior segment optical coherence tomography. RESULTS: Fifty-two patients (93 eyes) were recruited; 49 eyes were stratified to the FS group and 44 eyes to the MK group. The FS group had relatively even flap configurations, and the MK group had meniscus-shaped flaps. Mean differences between planned and actual flap thickness were 12.93 ± 8.89 and 19.91 ± 5.77 µm in the FS and MK groups, respectively. In thin flaps (100 to 110 µm), there was a significant disparity between the two groups (7.80 ± 4.71 and 19.44 ± 4.46 µm in the FS and MK groups, respectively). However, in thicker flaps (130 µm), comparable flap thickness disparity was achieved (18.54 ± 9.52 and 20.83 ± 5.99 µm in the FS and MK groups, respectively). Mean side-cut angle was 74.29 ± 5.79 degrees and 32.34 ± 4.94 degrees in the FS and MK groups, respectively. CONCLUSIONS: Comparable flap thickness predictability was achieved in thicker flaps (130 µm), while the FS laser technique yielded a more predictable result in thinner flaps (100 to 110 µm). Different flap morphology was observed in meniscus flaps in MK-LASIK and flap morphology in FS-LASIK.

Topiramate-induced acute angle closure with severe panuveitis: A challenging case report

A 36-year-old female presented with the complaints of pain, photophobia, redness, and sudden diminution of vision in both the eyes following topiramate for migraine treatment. On examination, there was panuveitis with angle-closure glaucoma in both the eyes with fibrinous exudate with pigments in the anterior chamber of the left eye. B scan revealed increased choroidal thickness in both the eyes. Serial anterior segment optical coherence tomography scans were done in the left eye to demonstrate the gradual resolution of the fibrin material from the anterior chamber. There was complete resolution of inflammation in both eyes following discontinuation of topiramate and treatment with systemic and topical steroids. There was an improvement in visual acuity in the left eye following complicated cataract surgery.