High Axial Length Research Articles

The Mirror Theory: Parallels between Open Angle and Angle Closure Glaucoma.

Glaucoma is a widespread ophthalmological disease, with a high impact and frequent visual morbidity. While the physiopathology of the two types of primary glaucoma (open angle and angle closure) has been studied, there seems to be little relationship between the two. In this study, we gather clinical and preclinical data to support the idea that the two primary glaucomas are "mirrored" in terms of morphological parameters and disease physiopathology. In short, primary angle closure glaucoma (PACG) is associated with hyperopia and low axial length, and primary open angle glaucoma (POAG) is associated with myopia and high axial length. Moreover, in PACG and in primary angle closure or primary angle closure suspect cases, while there is extensive iridotrabecular contact, the intraocular pressure (IOP) is still maintained in the lower half of the normal range throughout the evolution of the disease, which suggests a baseline trabecular hyperfiltration in PACG. In the opposite case, myopic eyes with open angles and a higher risk of developing POAG often have a baseline IOP in the upper half of the normal range, suggesting a baseline trabecular hypofiltration. As we explore clinical, genetic and animal model data regarding these opposing aspects, we hypothesize the existence of a mirroring relationship between PACG and POAG. Defining the relationship between the two potentially blinding diseases, with a high prevalence worldwide, may aid in understanding the mechanisms better and refining diagnosis and treatment. Thus, our theory has been named the Mirror Theory of Primary Glaucomas.

Posterior scleral reinforcement surgery effectively slows the rate of high myopic progression in children

To investigate the rate of axial length elongation and high myopia progression in operated eyes before and after posterior scleral reinforcement (PSR) surgery. This was a retrospective study. Children with pathological myopia treated with PSR at Beijing Tongren Hospital between May 2013 and May 2020 were recruited into the PSR surgery group. Children matched for age and myopia were recruited into the control group. All children underwent comprehensive ophthalmologic examinations. The presurgical and postsurgical rates of axial length elongation and myopic (spherical equivalent) progression were calculated. A total of 35 PSR patients were included in the study. The mean age was 6.5±3.0years (range 2 to 14years). Mean follow-up was 544days (range 216 to 1657days). The rate of axial length elongation was significantly less after posterior scleral reinforcement surgery (0.505±0.048mm per year prior to surgery; 0.382±0.045mm per year after surgery, P<0.001). The rate of myopic progression decreased after posterior scleral reinforcement surgery (1.162±0.118D per year prior to surgery; 0.153±0.437D per year after surgery, P=0.0239). There was no statistically significant difference in axial length elongation or myopic progression between pre-inclusion and post-inclusion in the control group. Moreover, the children's best-corrected visual acuity was significantly improved after posterior scleral reinforcement surgery (P<0.001). Posterior scleral reinforcement surgery effectively decreased the rate of high myopic progression and axial length elongation in children.

The Postoperative Visual and Refractive Outcomes of Trifocal and Extended Depth-of-Focus Intraocular Lenses in Patients with Different Biometric Characteristics.

We aimed to survey the potential correlation between biometric parameters and postoperative outcomes after implanting extended depth-of-focus (EDOF) intraocular lenses (IOLs) and trifocal IOLs. A retrospective cohort study was conducted, and patients receiving EDOF or trifocal IOL implantations were included. In total, 36 and 26 eyes were enrolled in the EDOF and trifocal groups, respectively. The primary outcomes of this study were the postoperative uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), and spherical equivalent (SE). The generalized linear model was applied to evaluate the adjusted odds ratio (aOR) and 95% confidence intervals (CIs) of primary outcomes in patients with different biometric characters. The final UDVA of the EDOF group was significantly better than that of the trifocal group (p = 0.020), and the UNVA and SE did not show significant differences between the two groups throughout the postoperative period (all p > 0.05). In a multivariable analysis, the UDVA was significantly better in the EDOF group than in the trifocal group (p = 0.038). For the subgroup analysis, the high axial length (AXL) value correlated to a lower postoperative UDVA in the EDOF group (both p < 0.05). Additionally, a large white-to-white (WTW) diameter was related to worse postoperative UNVA in the trifocal group (p = 0.042), and a high AXL was associated with higher SE in both the EDOF and trifocal groups (both p < 0.05). In conclusion, a high AXL correlates to worse postoperative outcomes in both the EDOF and trifocal IOLs, and trifocal IOL outcomes could be affected by large WTW diameters.

Optimizing Low-Dose [18F]FDG-PET/CT Scans: Ensuring Quality Amid Radiotracer Availability Challenges – Insights from a Peripheral Tertiary Care Center

Background: The introduction of positron emission tomography/computed tomography (PET/CT) has significantly advanced medical imaging. In oncology, 18F-fluorodeoxyglucose (18F-FDG) PET/CT is particularly crucial for staging, evaluating treatment response, monitoring follow-up, and planning radiotherapy. However, in resource limiting hospitals, the availability of fluorine-labeled 18F-FDG limits optimal scan acquisition. This study aims to determine the optimal dosage and acquisition time to maximize patient throughput during shortages. Aim and Objective: To optimize low-dose 18F-FDG scan protocols while maintaining high image quality despite radiotracer availability challenges. Materials and Methods: PET/CT scans were performed using GE’s Discovery IQ 5-ring, 16-slice system within 40–60 minutes of intravenous 18F-FDG injection. The protocol was adjusted to a low-dose (0.05 mCi/kg of 18F-FDG), and the PET data acquisition time was increased to 3 min per bed position to ensure image quality. Results: Notable differences were observed in image quality scores based on varying acquisition times, with the extended acquisition time helping maintain diagnostic standards despite reduced tracer doses. Conclusion: The high sensitivity and long axial length of the PET/CT system (with five rings spanning 26 cm AFOV) can significantly alleviate the challenges faced by cyclotron-dependent centers. By leveraging the increased sensitivity, we successfully reduced the injected activity rather than the scan time to address the tracer shortage at our institute. This approach proved to be effective in maintaining image quality and patient care standards.

Risk Factors for Retinal Detachment in Marfan Syndrome After Pediatric Lens Removal

Purpose: To determine Retinal Detachment (RD) risk factors after lens removal surgery in children with Marfan syndrome.Design: Retrospective case control study.Methods:Setting: Institutional case-seriesStudy population: All children (<18 years) with Marfan syndrome that underwent lens removal surgery.Observation procedure: Clinical and surgical characteristics were extracted from children's electronic files: age, Axial Length (AL), gender, number of surgeries received, Intra Ocular Lens (IOL) implantation at the first surgery, complete removal of the capsular bag, final best corrected visual acuity.Main outcome measure: Risk factors associated with RD occurrence.Results: Among 158 eyes included (85 children), 35 eyes (22.2%) developed RD during follow-up. Bilateral detachment occurred in 11 patients (45.8%). Age at the time of the lens removal surgery was not different between groups. Children in the RD group had a higher AL (p<.001), longer follow-up, IOL implantation, and capsular residue. Multivariate analysis identified capsular residue (odds ratio [OR] 16.8; 95% confidence interval [CI], 1.9-148.8; P=0.01), and axial length by (OR 1.3; 95% CI, 1.01-1.7; P=0.03) as predictors for RD.Conclusion: Marfan syndrome children with increased AL were more likely to develop a RD after lens surgery. When considering lens removal surgery in a pediatric population presenting Marfan's syndrome, a complete capsular removal seemed to be the safer option regarding RD risk.

Correlation between axial length and choroidal changes in high myopia

Background Swept-source optical coherence tomography (SS-OCT) can furnish high-resolution structural images of the choroid for chorioretinal atrophy in high myopia. Aim The present study aimed to detect the axial length and choroidal thickness correlation in high myopia using SS-OCT. Using SS-OCT seeks to establish the choroidal thickness and axial length correlation in extreme myopia individuals. Patients and methods A prospective cross-sectional study that was carried out on two groups of patients, group A involved 60 high myopic eyes with myopic refractive error less than or equal to −6.00 diopters (D) and axial length greater than or equal to 26.5 mm which was divided into group A1 which included 30 eyes with axial length less than 29 mm and group A2 that involved 30 eyes with axial length greater than or equal to 29 mm. Group B (control group) included 30 emmetropic eyes with a normal range of axial length (23.5–24.5 mm). Results A high significant axial length was detected in group A2 in contrast to groups A1 and B with P value less than 0.001. The subfoveal choroidal thickness and choroidal thickness in other locations (1 mm superior, 1 mm inferior, 1 mm nasal, and 1 mm temporal to the fovea) were significantly thinner in group A2 than groups A1 and B (P &lt;0.001). A statistically significant inverse correlation (P &lt;0.001) was identified between the choroidal thickness at various locations and the axial length in groups A1 and A2. Conclusion Negative correlation was detected between axial length and both subfoveal choroidal thickness and best corrected visual acuity in patients with high myopia. There was a significant positive correlation between axial length and myopic refractive error.

Retinal complications post posterior chamber phakic intraocular lens implantation at a tertiary eye hospital in the Eastern Province of Saudi Arabia.

Phakic intraocular lenses treat higher degrees of myopia not possible previously with conventional refractive surgery. The aim of this study is to report the incidence and risk factors of retinal complications after posterior chamber PIOL implantation and assess the differences in biometric parameters between patients who developed such complications versus those who did not. This retrospective study recruited 514 patients who underwent ICL implantation to correct myopia at a tertiary eye hospital center in the Eastern province of Saudi Arabia. Follow up period was at least one year. Medical records of the patients were reviewed to obtain the required data. Associations between respondents' characteristics and retinal complications were evaluated using the Chi-squared test. The mean (SD) age was 27.7 (± 6.5) years ranging from 18 to 47. Laser treatment was performed in 14 cases (2.7%). Retinal complications occurred in six cases (1.2%). The risk of retinal complication was significantly higher among patients with high axial length (OR = 1.3, 95% CI 1.2, 1.4) and patients with high pre-spherical equivalent before ICL (OR = 1.09, 95% CI 1.03, 1.4). Patients with higher axial length and higher pre-spherical equivalent before ICL implantation are at high risk of retinal complications.

Proptosis in Adult Onset of Unilateral High Myopia Patient : A Case Report

Introduction : Unilateral high myopia is an uncommon refractive condition, because two eyes typically grow bilaterally by the same amount and resulting in symmetric myopia. Proptosis can appeared due to high axial length in myopia.&#x0D; Case Illustration : A 41-year-old female patient complain protruding eyeball in her left eye, gradually decrease vision, eye discomfort, and headache in her left eye since last year. There was no family history of eye disease, trauma or mass. On examination, her left eye was proptotic 3mm, best corrected visual acquity (BCVA) was 6/21 with -10.00 Sphere, and high intraocular pressure 23 mmhg. Her right eye BCVA 6/6 with -2.75 Sphere, other within normal limits. Her fundus examination showed features of high myopia and B-scan ultrasonographic showed different in axial lengths in both eyes. Orbita computerized tomography non contrast confirmed enlarge globe to posterior and proptotic in left eye.&#x0D; Discussion : Unilateral high myopia developing in adult onset is a rare case. It appears to be a progressive condition that have a variable age of onset. Amblyopic eye, high intraocular pressure and proptosis demonstrated as the symptoms of unilateral high myopia in this patient. Left eye proptosis confirmed by CT orbita appears secondary due to elongation anteroposterior of the globe / changesin axial components of the eye.&#x0D; Conclusion : High myopia can be a consideration of proptotic eye beside of mass/ tumor. Several studies to investigate patients with unilateral high myopia should be done to know the etiology and progression of the disease, thus can achieve good treatment and visual outcomes for patient.

The Effect of Myopic Control between the Dual-Focus Contact Lenses and High-Concentration Atropine in an Asian Population.

We aim to investigate the myopic control effect of high-concentration atropine (ATR) and dual-focus contact lenses (DFCLs). A retrospective cohort study was conducted. A total of 182 eyes in 91 individuals who used high-concentration ATR (0.125%) and another 70 eyes in 35 individuals who used DFCLs were enrolled in the ATR and DFCL groups, respectively. The primary outcomes were spherical equivalent refraction (SER) progression and axial length (AXL) elongation. The generalized estimate equation was utilized to yield the adjusted odds ratio (aOR) and 95% confidence interval (CI) of cycloplegic SER progression and AXL elongation between groups. According to the multivariable analysis, the change in cycloplegic SER progression was similar between the DFCL and ATR groups (aOR: 1.305, 95% CI: 0.247-2.515, p = 0.803). The DFCL group demonstrated a numerically higher rate of AXL elongation compared to the ATR group (aOR: 1.530, 95% CI: 0.980-1.894, p = 0.051). In the subgroup analysis, cycloplegic SER progression was insignificant between ATR and DFCL users in different subgroups (all p > 0.05). The DFCL patients with moderate astigmatism and high AXL (both p < 0.001) presented a high risk of AXL elongation. In conclusion, DFCL usage demonstrated similar myopic control of cycloplegic SER and AXL compared to high-concentration ATR, while DFCLs showed lower AXL control, mainly in patients with moderate astigmatism and high AXL.

The Relationship Between Anthropometric Z-Score Measurements and Ocular Structures in Turkish Children.

Objective (Aim): This study explores the contact between anthropometric Z-score values and ocular parameters in children. Recent studies investigated the relationship, and contact between anthropometric measurements and ocular parameters in children, and height, weight, body mass index, and percentile curves are mostly used as anthropometric data. However, today, different scoring systems such as "Z-score" classify anthropometric values. Methods: Height and body mass index Z-scores were calculated for 725 children. Biometric and refractive measurements of all children were noted. For different reference values, those with a Z-score below the negative value of the reference were defined as a low Z-score, those between the negative and positive value of the reference were defined as a normal Z-score, those with a Z-score greater than the positive value of the reference were defined as a high Z-score. The mean ocular measurement results in the low, normal, and high Z-score groups were compared, and they were pointed to reach the reference value in both negative and positive sides which created the foremost critical contrast between the groups. Results: For a value of "-1" and "+1.5" in the height Z-score, from low to normal and from there to high Z-score group, axial length, and average corneal radius increased, and average corneal power decreased significantly. Anterior chamber depth increased from normal to high Z-score group, but no critical distinction was made between low and normal Z-score groups. Moreover, no critical distinction was observed in spherical equivalent refraction, central corneal thickness for height, and all values of body mass index. Conclusion: Considering a Z-score value of "-1" and "+1.5" as a reference value in children and anticipating the changes that may happen in the ocular structures of children at both ends of the Z-score, it may be useful to understand the effect of body development on ocular development more. Abbreviations: AL = Axial Length, ACD = Anterior Chamber Depth, BMI = Body Mass Index, NCHS = The United States National Center for Health Statistics, WHO = World Health Organization, NFHS 2 = National Family Health Survey 2, SER = Spherical Equivalent Refraction, CR = Average Corneal Radius, CP = Average Corneal Power, CCT = Central Corneal Thickness, HFAsZ = Height for Age Z-Score, BMIsZ = BMI for Age Z-Score, L = Low Z-score, N = Normal Z-score, H = High Z-score.

Accuracy of Different Intraocular Lens Calculation Formulas in Patients with High Axial Myopia

Background The two main problems encountered in calculation of intra ocular lens power are the measurement of the proper axial length (AL), and the lack of accuracy of the available formulas that calculate the power of the intra ocular lens in cases of eyes with high axial length. Aim of the Work To compare the accuracy of intraocular lens (IOL) calculation formulae (Holladay I, Haigis, SRK/T, Hoffer Q, Holladay II, and Barrett Universal II) in the prediction of postoperative refraction for eyes with AL 26.0 mm or more. Patients and Methods A prospective study was carried on forty-seven eyes of forty-seven patients. All the patients were managed at Ain Shams University Hospitals in cooperation with a specialized centre between April 2019 and March 2020. Results Mean absolute error (MAE) was calculated for each formula showed that the least MAE is for Barrett Universal II formula. SRK/T formula is the 2nd lower MAE followed by Haigis formula and the last is Holladay II formula. The scatter plots between AL and absolute error from each of the six calculations formulae was done and showed that Barrett universal II has negative correlation with AL. As for SRK/T and Haigis formulae there is a linear correlation. Numerical Predictive Error showed that SRK/T formula had the lowest mean numerical error followed by Haigis formula then Barrett Universal II and last came Holladay II formula. Conclusion for high axial myopic eyes, the Barrett Universal II formula is the best in this group of patients and provide the lowest mean absolute error, highest percentage of eyes within ≤ ± 0.50 D and the lowest risk of refractive surprise compared to other IOL power calculation formulae. Then comes Haigis and SRK/T formulae which performed similarly and provide a good predictable outcome then at last came Holladay II formula.

Analysis of Bilaterality and Symmetry of Posterior Staphyloma in High Myopia.

The purpose of this study was to examine bilaterality and symmetry of posterior staphyloma (PS) in high myopic eyes. Methods: This cross-sectional and non-interventional study assessed 473 high myopic eyes [axial length (AL) ≥ 26 mm] of 259 patients. Patients underwent an ophthalmological examination including multimodal-imaging and myopic maculopathy grading according to Atrophic/Tractional/Neovascular (ATN) system, presence and subtype of PS, and severe pathologic myopia (PM). Bilaterality of PS and subtype's symmetry between eyes of the same patient was assessed. Four groups were analyzed: (1) bilateral vs. unilateral PS's eyes. Within bilateral group, symmetric vs. asymmetric subtypes according to (2) Curtin's classification, (3) Ohno-Matsui's classification, and (4) primary/compound subtypes. Results: Out of the total, 334 myopic eyes of 167 patients were included. The 92.8% (n = 310/334) of the eyes presented PS and was bilateral in 85.6% (n = 143/167) of the patients. Bilateral eyes showed significantly (p < 0.01) greater AL, severe PM, A and N components vs. unilateral PS. AL-difference between both eyes was greater in unilateral PS (p < 0.01). Among bilateral PS, the subtype was symmetric in 79 (55.2%), 84 (58.7%), and 115 (80.4%) patients according to Curtin's classification, Ohno-Matsui's classification, and primary/compound; respectively. The asymmetric group presented worse best-corrected visual acuity (p < 0.01), higher AL (p < 0.01), incidence of PM, and severe PM (p < 0.05). Conclusions: PS was bilateral in most of the patients without clinical differences between both eyes, being symmetrical in more than half of bilateral cases. Patients with bilateral PS showed higher myopic maculopathy, AL, and incidence of severe PM than unilateral PS.

How Myopia and Glaucoma Influence the Biomechanical Susceptibility of the Optic Nerve Head.

The purpose of this study was to assess optic nerve head (ONH) deformations following acute intraocular pressure (IOP) elevations and horizontal eye movements in control eyes, highly myopic (HM) eyes, HM eyes with glaucoma (HMG), and eyes with pathologic myopia (PM) alone or PM with staphyloma (PM+S). We studied 282 eyes, comprising of 99 controls (between +2.75 and -2.75 diopters), 51 HM (< -5 diopters), 35 HMG, 21 PM, and 75 PM+S eyes. For each eye, we imaged the ONH using spectral-domain optical coherence tomography (OCT) under the following conditions: (1) primary gaze, (2) 20 degrees adduction, (3) 20 degrees abduction, and (4) primary gaze with acute IOP elevation (to ∼35 mm Hg) achieved through ophthalmodynamometry. We then computed IOP- and gaze-induced ONH displacements and effective strains. Effective strains were compared across groups. Under IOP elevation, we found that HM eyes exhibited significantly lower strains (3.9 ± 2.4%) than PM eyes (6.9 ± 5.0%, P < 0.001), HMG eyes (4.7 ± 1.8%, P = 0.04), and PM+S eyes (7.0 ± 5.2%, P < 0.001). Under adduction, we found that HM eyes exhibited significantly lower strains (4.8% ± 2.7%) than PM+S eyes (6.0 ± 3.1%, P = 0.02). We also found that eyes with higher axial length were associated with higher strains. Our study revealed that eyes with HMG experienced significantly greater strains under IOP compared to eyes with HM. Furthermore, eyes with PM+S had the highest strains on the ONH of all groups.

Influencia de la longitud axial ocular en el grosor de la capa de fibras nerviosas peripapilar medido con tomografía de coherencia óptica

BackgroundOptical coherence tomography (OCT) allows the measurement of the peripapillary optic nerve fiber layer (RNFL) thickness. The effect of ocular axial length (AL) on RNFL thickness measurement may be relevant in the interpretation of OCT results in diagnosing optic nerve diseases. PurposesTo assess the influence of ocular AL on RNFL thickness and on optic disc topographic parameters (optic disc area, rim area and cup volume) measured by OCT, in healthy individuals. MethodA sample of 109 healthy eyes classified into three groups according to AL (A: AL <22mm; B: AL 22–24.5mm; C: AL >24.5mm) was studied. RNFL thickness and optic disc topographic parameters were measured using Swept-Source OCT Triton (Topcon Corporation, Tokyo, Japan) and were compared between groups using a variance analysis. Correlation between the AL and the study variables was performed using a Pearson's correlation coefficient test. ResultsThe RNFL thickness was lower in eyes with higher AL in the superior (r=−0.41; p<0.001), inferior (r=0.58; p<0.001) and nasal (r=−0.43; p<0.001) quadrants, in the mean value of the RNFL (r=−0.49; p<0.001), optic disc area (r=−0.40; p<0.001) and rim area (r=−0.25; p=0.01). ConclusionAL is negatively correlated with RNFL thickness and optic disc topographic parameters measured by Swept-Source OCT Triton (Topcon).

Influence of posterior staphyloma in myopic maculopathy and visual prognosis.

Posterior staphyloma is a hallmark of high myopia and its presence associates to greater degrees of myopic maculopathy. Nonetheless, its development, repercussion on visual function and relationship with maculopathy components, is still unclear. The objective was to analyze the impact of posterior staphyloma on the incidence and severity of myopic maculopathy and its repercussion on visual prognosis. Cross-sectional study conducted on 473 consecutive eyes of 259 highly myopic patients examined at Puerta de Hierro-Majadahonda University Hospital (Madrid, Spain). All patients underwent complete ophthalmologic examination including best corrected visual acuity (BCVA), axial length (AL), myopic maculopathy classification according to ATN system (atrophic/traction/neovascularization), determined the presence of posterior staphyloma, pathologic myopia (PM) and severe PM. Multimodal imaging were performed including fundus photography, optical coherence tomography (OCT), OCT-angiography, fundus autofluorescence and/ or fluorescein angiography. Out of the total, 70.65% were female patients (n = 173/259), mean BCVA was 0.41 ± 0.54 logMAR units and mean AL was 29.3 ± 2.6 mm (26-37.6). Posterior staphyloma was present in 69.4% of eyes. Eyes with posterior staphyloma compared to non-staphyloma were older (p < 0.05), had greater AL (p < 0.01), worse BCVA (p < 0.01) and higher stage in ATN components (p < 0.01). Moreover, compound subgroup showed worse BCVA (p < 0.01) and greater stage in each of the ATN components (p < 0.01). Staphylomas with macular involvement presented worse BCVA (p < 0.01), higher AL (p < 0.01), and greater ATN (p < 0.05). The risk of posterior staphyloma presence in eyes with PM and severe PM eyes was 89.8% and 96.7%, respectively. Posterior staphyloma was the best predictor for BCVA in myopic patients (p < 0.01). Posterior staphyloma's presence determines high risk of myopic maculopathy and therefore worse visual prognosis, especially those with macular involvement. Posterior staphyloma represented the best predictor for BCVA in highly myopic patients.

Ocular axial length influence on peripapillary retinal nerve fiber layer thickness measurement with optical coherence tomography

BackgroundOptical coherence tomography (OCT) allows the measurement of the peripapillary optic nerve fiber layer (RNFL) thickness. The effect of ocular axial length (AL) on RNFL thickness measurement may be relevant in the interpretation of OCT results in diagnosing optic nerve diseases. PurposeTo assess the influence of ocular AL on RNFL thickness and on optic disc topographic parameters (optic disc area, rim area and cup volume) measured by OCT, in healthy individuals. MethodsA sample of 109 healthy eyes classified into 3 groups according to AL (A: AL<22mm; B: AL 22−24.5mm; C: AL>24.5mm) was studied. RNFL thickness and optic disc topographic parameters were measured using Swept-Source OCT Triton (Topcon) and were compared between groups using a variance analysis. Correlation between the AL and the study variables was performed using a Pearson's correlation coefficient test. ResultsThe RNFL thickness was lower in eyes with higher AL in the superior (r=−0.41; p<0.001), inferior (r=0.58; p<0.001) and nasal (r=−0.43; p<0.001) quadrants, in the mean value of the RNFL (r=−0.49; p<0.001), optic disc area (r=−0.40; p<0.001) and rim area (r=−0.25; p=0.01). ConclusionsAL is negatively correlated with RNFL thickness and optic disc topographic parameters measured by Swept-Source OCT Triton (Topcon).

Corneal biomechanical properties in myopic and emmetropic children.

The purpose of this study was to investigate the relationship between corneal biomechanics and ocular morphology in myopic children and adolescents. The study included 170 right eyes, from 170 patients under the age of 18 years, who underwent a complete ophthalmologic examination, gathering the following data: spherical equivalent (SE) (under pharmacological cycloplegia), biomechanical parameters - corneal hysteresis (CH) and corneal resistance factor (CRF), structural parameters - axial length (AL) and central corneal thickness (CCT). The average age of the patients was 15.26 years old (55.29% girls, 44.70% boys). Out of the 170 eyes, 111 were myopic eyes and 59 were emmetropic. Myopic eyes had a significantly lower CH (p=0.001), CRF (p=0.002) and CCT (p=0.009), and higher AL (p<0.001) than emmetropic eyes. The AL and CCT were significantly higher in myopic males, compared to myopic females (p<0.001 and 0.001). In myopes, we found statistically significant negative correlations between AL and CH (Pearson's r=-0.218), CRF (r=-0.226) and also SE (r=-0.539), and positive between SE and either CH (r=0.193) or CRF (r=0.201). Corneal biomechanical properties are significantly related to myopia parameters in children.

Myopic maculopathy and posterior staphyloma. Correlation with ATN classification and severe pathological myopia

AbstractPurpose: The aims of this study were: (1) to correlate posterior staphyloma with the ATN classification; (2) identify differences in clinical characteristics in terms of axial length (AL), age and best corrected visual acuity (BCVA) in eyes with the presence and absence of posterior staphyloma; (3) correlate the presence of posterior staphyloma with severe pathological myopia.Methods: This was a cross‐sectional and observational study developed in consecutive patients with high myopia. A complete ophthalmological examination, classification of myopic maculopathy according to the ATN grading system, staphyloma classification according to Curtin, and multimodal imaging tests (retinography, swept‐source OCT, autofluorescence and OCT‐angiography) were performed.Results: 336 eyes of 178 patients with high myopia were included. 71.4% of the sample were woman. The mean AL was 29.7 ± 2.6 mm (26–36.7). The mean age was 62.7 ± 13.1 years (27–92). The BCVA was 0.5 ± 0.3 (0–1). 238 eyes (70.8%) presented staphyloma; classifying 73.5% (n = 175/238) as simple and 26.5% as compound (n = 63/238). The most frequent types of staphylomas were type 2 and type 3, both present in 18.1% of the total (n = 43/238). Eyes with staphyloma had higher AL, worse BCVA and older age (p &lt; 0.01), with no differences between sexes (p &gt; 0.05). When differentiating between eyes with simple staphyloma and compound staphyloma, statistically significant differences were observed with respect to AL (p &lt; 0.01), being higher in compound staphylomas. The severe pathological myopia subgroup (LA &gt; 29.5 mm) presented a higher incidence of posterior staphyloma, with statistically significant differences (p &lt; 0.01). Regarding the ATN classification, when analysing the eyes with the presence and absence of staphyloma, statistically significant differences (p &lt; 0.01) were observed in the three components (atrophic [A], tractional [T] and neovascular [N]); having more advanced stages of A, T and N the eyes with staphyloma.Conclusions: Posterior staphyloma in highly myopic patients is a crucial finding in the progression of myopic maculopathy, being related to worse visual acuity, greater AL, older age and more advanced stages of the ATN classification. There is a higher prevalence of posterior staphyloma in eyes with severe pathological myopia.

Analysis on the effect of eye globe diameters on the biomechanics of posterior ocular tissues during horizontal adduction

Abstract In this work, an attempt has been made to analyze the influence of pathological changes in eye globe dimensions towards the mechanical responses of optic nerve head tissues during eye adductions. For this study, a 3D baseline model geometry of posterior ocular tissues has been constructed. The eye globe diameters of the model are modified to mimic the changes in ocular globe morphology in control, glaucoma, myopia and glaucoma with myopia conditions. Adductions are simulated for each modified model as the rotation of the globe from 1o to 10o in steps of 1o. von Mises strain in lamina cribrosa (LC) and posterior displacement of LC are estimated. Results show that strains developed in LC and its posterior displacement are higher in diseased eyes compared to healthy eyes. It appears that eyes with higher axial length and globe anisotropy are more susceptible to optic nerve head damage. This study might be extended to assess the progression of glaucomatous optic neuropathy.

Risk factors of surgical failure in combined phacoemulsification and excisional goniotomy for angle-closure glaucoma.

To evaluate the therapeutic success, and risk factors for combined phacoemulsification and Kahook Dual Blade excisional goniotomy (Phaco/KDB) in primary angle-closure glaucoma (PACG). A retrospective review was conducted on glaucoma patients who underwent Phaco/KDB between September 2019 and August 2021 at 2 ophthalmology centers. Complete success was defined as unmedicated intraocular pressure (IOP) ≤ 18mmHg with no further glaucoma surgery, while the medicated IOP ≤ 18mmHg was defined as qualified success with lesser medications than at baseline. Seventy-two eyes (64 patients) with a mean age of 67.1 ± 8.1years were included in this study, and 70.2% were female. The mean medicated baseline IOP decreased from 23.4 ± 8.1 to 16.6 ± 3.9mmHg at an average of 11.6 ± 3.7months of follow-up (- 29.1%; P < 0.00). Medications decreased from 2.6 ± 1.3 to 0.4 ± 0.9 (- 82.6%; P < 0.001). Complete success and qualified success were achieved in 65.3% and 79.2% of eyes, respectively. Male gender [hazard ratio (HR): 6.00 (1.57-22.9); P = 0.009] was observed a risk factor for surgical failure, whereas higher axial length (HR:0.37 (0.16-0.86); P = 0.021), and a combined circumferential goniosynechialysis procedure (HR: 0.13 (0.02-0.74); P = 0.022) lowered the risk of surgical failure. Hyphema, postoperative shallowing anterior chamber, and IOP spike were the most common complications. The cumulative survival proportion for qualified success at 12months was 82.5% ± 0.05 (95% CI, 0.70-0.90). Phaco/KDB provided acceptable therapeutic success rate and may, therefore, be recommended in patients with coexisting cataract and PACG. Identifying patients with risk factors preoperatively may help clinicians predict surgical success.