Small Pupil Research Articles

Differentiation of Horner Syndrome and Physiological Anisocoria by Automated Pupillometry.

The differentiation of Horner syndrome from physiological anisocoria is important yet clinically challenging. We investigated the diagnostic accuracy of pupillometry to discriminate Horner syndrome from physiological anisocoria compared to pharmacological testing with the alpha-2-agonist apraclonidine, which is considered the current gold standard. Forty-four adult patients, mostly referred to our neuro-ophthalmology service for evaluation of anisocoria, were included. Automated binocular pupillometry was performed under standardized light conditions before and >30 minutes after instillation of 1% apraclonidine eye drops. A positive apraclonidine test indicating unilateral Horner syndrome was defined as an increase of pupil size in the smaller pupil and decrease of size in the larger pupil. Receiver operator characteristic curves were calculated to find the best pupillometric parameter discriminating Horner syndrome from physiological anisocoria. We found that the parameters measuring the pupillary dilation lag using pupillometry could reliably discriminate Horner syndrome from physiological anisocoria compared to pharmacological testing. Calculating the change of anisocoria at 3-4 seconds after light-off relative to the anisocoria at the end of the light-on period (Δ3-4) may be most suitable to rule out Horner syndrome reaching a sensitivity of 95% and specificity of 68% using a cutoff of 0.35 mm. Our results indicate that pupillometry is a robust tool to measure the dilation lag in Horner syndrome and, therefore, to distinguish pathological from physiological anisocoria obviating pharmacological testing. The high sensitivity of the test will allow to identify the patients with Horner syndrome requiring further investigation.

Efficacy of intracameral mydriatics in pediatric lens surgery.

Introduction To evaluate the efficacy of intracameral administration of Mydrane® in children undergoing lens surgery. Methods We set up a single center prospective cohort trial including 40 consecutive patients between 8 weeks and 17 years old who were planned for lens surgery, including cataract, persistent fetal vasculature (PFV) or lens subluxation. We injected 0,1 ml of intracameral Mydrane at the beginning of surgery, no preoperative mydriatic eye drops were used. The aim of the study was to measure pupil size, and to monitor the evolution of the pupil size during surgery and the need for additional pupil expanding techniques. Results In 30 patients (75% (95%CI: 59 - 87%)), we did not need additional manipulations to obtain sufficient pupillary dilatation to perform the surgery and to implant an intraocular lens (IOL) following the bag-in-the-lens (BIL) technique. In the remaining 10 patients (25%), we saw an initiation of dilatation, but not to the required pupil diameter to continue the surgery without additional surgical maneuvers. The duration of surgery was significantly longer in the partial response group, reflecting the need for additional surgical steps. A significant relation between increase of pupillary diameter and age (P = 0.003), gender (P = 0.032) and horizontal corneal diameter (P < 0.001) could be shown. Even at baseline there is a larger pupil diameter in eyes with larger horizontal corneal diameters (p=0.039). No adverse events were observed during this study. Conclusion Intracameral administration of Mydrane resulted in some degree of dilatation in all eyes in this series, 75% of eyes did not need additional techniques to proceed with the surgery. Smaller pupils at baseline, younger age, male sex and small horizontal corneal diameter were related to a poorer response to Mydrane. The mydriasis persisted for the entire duration of the surgery, no ocular adverse events were observed during this study. This leads us to conclude that intracameral Mydrane is an effective and safe way to dilate the pupil in pediatric lens surgery.

Floppy iris. How is floppy iris syndrome managed? What do urologists and ophthalmologists say?

This study focuses on the effect of chronic treatment on the eye, regarding the so-called Intraoperative Floppy Iris Syndrome (IFIS) or Floppy Iris Syndrome, which can occur during cataract surgery. The study aimed to establish the influence of tamsulosin, used in benign prostatic hyperplasia (BPH) treatment on the iris, during cataract surgery, considering the increased incidence of both conditions in older age. This study included one hundred male patients, operated on for cataracts at the Ofta Total Clinic and Dr. Stănilă Medical Centre, in Sibiu, out of 601 patients operated on for cataracts between February and October 2022. Of the 100 patients, 24 used medication for BPH. 5 patients used prostamol, a phytotherapeutic preparation, which is an extract from Serenoarepens, and the remaining 19 used tamsulosin, which is an alpha-blocker, most commonly used in the treatment of BPH, considered the first-line treatment option. In 15 patients, we intraoperatively managed, a medium mydriasis through pharmacological dilation, including intracameral administration of phenocaine and mechanical dilation or stripping. In 4 patients it was necessary to apply iris dilators. Due to the small pupil in 2 patients, we caught the iris in the phacoemulsification probe, and a small, incomplete iris coloboma was formed. Sometimes, there was a turnover of Descemet in 4 patients. The pupil remained semi-dilated and slightly areflective in the patients to whom we applied iris hooks. The patients' visual acuity was satisfactory, between 0.9 and 0.6. The topic gives rise to many discussions. It seems that stopping the administration of tamsulosin for a short time does not help the occurrence of IFIS, because the iris lesions seem irreversible. Patients at risk of developing cataracts should be evaluated and possibly referred to an ophthalmologist to determine surgery before starting treatment for BPH and to competently assess the administration of this medication. Collaboration between urologists and ophthalmologists is required for patients prone to the appearance of cataracts since both conditions are frequently encountered in elderly patients.

Investigating causal effects of pupil size on visual discrimination and visually evoked potentials in an optotype discrimination task.

Pupil size primarily changes to regulate the amount of light entering the retina, optimizing the balance between visual acuity and sensitivity for effective visual processing. However, research directly examining the relationship between pupil size and visual processing has been limited. While a few studies have recorded pupil size and EEG signals to investigate the role of pupil size in visual processing, these studies have predominantly focused on the domain of visual sensitivity. Causal effects of pupil size on visual acuity, therefore, remain poorly understood. By manipulating peripheral background luminance levels and target stimulus contrast while simultaneously recording pupillometry and EEG signals, we examined how absolute pupil size affects visual discrimination and visually evoked potentials (VEP) in a task using optotype mimicking the Snellen eye chart, the most common assessment of visual acuity. Our findings indicate that both higher background luminance levels and higher target contrast were associated with improved target discrimination and faster correct reaction times. Moreover, while higher contrast visual stimuli evoked larger VEPs, the effects of pupil size on VEPs were not significant. Additionally, we did not observe inter-individual correlations between absolute pupil size and discrimination performance or VEP amplitude. Together, our results demonstrate that absolute pupil size, regulated by global luminance level, played a functional role in enhancing visual discrimination performance in an optotype discrimination task. The differential VEP effects of pupil size compared to those of stimulus contrast further suggested distinct neural mechanisms involved in facilitating visual acuity under small pupils.

Mental effort during mindless reading? Pupil fluctuations indicate internal processing during levels of inattention.

Mind wandering, an experience characterized by a reduced external focus of attention and an increased internal focus, has seen significant theoretical advancement in understanding its underlying cognitive processes. The levels-of-inattention hypothesis posits that in mind wandering, external attention is reduced in a graded fashion, reflecting different levels of weak versus deep attentional decoupling. However, it has remained unclear whether internal processing during mind wandering, and mindless reading in particular, requires effort and, if so, whether it is graded or distinct. To address this, we analyzed pupil size as a measure of cognitive load in the sustained-attention-to-stimulus task during text reading. We examined whether decoupled external attention is linked to an overall reduction in workload and whether internal focus of attention is graded or represents a distinct cognitive process. Overall, overlooking errors in the text was associated with a small pupil size, indicating reduced effortful processing. However, this effect varied with error type: overlooking high- or medium-level errors (weak decoupling) resulted in reduced pupil size, while overlooking low-level errors (deep decoupling) had no effect on pupil size. Moreover, detecting an error (at any processing level) elicited a task-evoked pupillary response, which was absent when it was overlooked. These findings suggest that weak decoupling reduces internal resource-demanding processing and are in line with the hypothesis that large pupils during deep decoupling may be associated with distinct states of effortful internal processing. They further support both the levels-of-inattention hypothesis and the notion that internal focus is a distinct mode of deeply decoupled processing. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Capsular Waves: A Warning Indicator for Potentially Malpositioned Intraocular Lenses.

To share examination findings of the lens capsule which may act as an indicator for malpositioned intraocular lenses (IOL). Single large multi-specialty private practice, Houston, Texas, USA. Focused, observational case series. A review of pre-operative images of malpositioned single-piece IOLs with at least one haptic in the ciliary sulcus was conducted. The review included five cases who were referred to a single large multi-specialty private practice from June 2023 to December 2024 for an evaluation of posterior capsular opacification (PCO) and potential Nd:YAG capsulotomy. A total of five eyes which previously had undergone cataract surgery and were referred for Nd:YAG capsulotomy for PCO were identified on slit lamp examination to have capsular waves, defined as a centripetal and circumferential striated pattern of PCO that results from a fused anterior and posterior capsule with at least part of the IOL anterior to the capsule. While one eye exhibited transillumination defects and pigment dispersion, the remainder of eyes did not. In some cases, the capsular wave was the only clue to IOL malpositioning due to a small pupil. These eyes had single-piece IOLs with at least one haptic in the sulcus and required subsequent IOL repositioning or exchange. If capsular waves are seen on slit lamp exam, a thorough inspection of IOL placement should be conducted, especially before treatment with Nd:YAG capsulotomy. Capsular waves result from anterior and posterior capsule contact with an anteriorly situated IOL. This finding is a potential indicator of at least part of an IOL positioned anterior to the anterior capsule.

Safety and efficacy of phacoemulsification and intraocular lens implantation through a small pupil using iris retractors

Objectives: The objectives of this study were to study the postoperative (postop) outcome of phacoemulsification using iris retractors in patients with small pupils and compare it with well dilating pupils by comparing the final visual acuity, intra- and post-operative complications, endothelial cell count, and anterior chamber (AC) depth of patients with small pupil with those of well-dilated pupil. Materials and Methods: This was a prospective cross-sectional study for December 2020–March 2022 which included 86 eyes of 86 patients. For study purposes eyes were divided into two groups, Group 1 consisted of 43 subjects with post-mydriatic dilatation (≤5 mm), and Group 2 consisted of 43 cases with well-dilated pupils ≥6 mm. Results: Group 1 intraoperatively difficulties faced – incomplete rhexis or runoff (41.86%, n = 43), incomplete nucleus chopping (32.55%, n = 43) and retained cortical matter (46.51%, n = 43) noted, managed by applying iris retractors while group 2 faced no difficulties during surgery. In group 1, 33 patients (76.74%) had no complications. Retained cortex was seen in 5 patients (11.62%) and was the most common complication. In group 2, 41 patients (95.34%) had uneventful cataract surgery while 2 patients (4.64%) had minimally retained cortex on post op day 1. Best-corrected visual acuity (BCVA) – 3 months follow-up was good (Snellen-6/6–6/18, logMar 0.00–0.48) in 90.7% in group 1 and 97.7% in group 2. BCVA was borderline (Snellen 6/24–6/60, logMar 0.60–1.00) in 9.30% in group 1 and 2.32% in group 2. Group 1 mean pre-operative endothelial cell density (2528.44 ± 61.26) in group 2 (2457.05 ± 91.17) was significant. On postop day 1 ,1 week and at 3 months endothelial cell density decreased by 4.27%,7.75%,11.92% respectively compared to preoperative values in group 1 while in group 2 it decreased by 2.20%,3.84%,5.40% respectively compared to preoperative values. AC depth was shallower (2.49 ± 0.39) in patients in which complication was noted compared to AC depth (2.72 ± 0.41) in which there was no complication, P value being 0.010 is significant. Conclusion: Small pupil poses some difficulty in cataract surgery which can be overcome by timely intervention by expert surgeons and complication rates can be minimised.

Pupil contagion variation with gaze, arousal, and autistic traits

Pupillary contagion occurs when one’s pupil size unconsciously adapts to the pupil size of an observed individual and is presumed to reflect the transfer of arousal. Importantly, when estimating pupil contagion, low level stimuli properties need to be controlled for, to ensure that observations of pupillary changes are due to internal change in arousal rather than the external differences between stimuli. Here, naturalistic images of children’s faces depicting either small or large pupils were presented to a group of children and adolescents with a wide range of autistic traits, a third of whom had been diagnosed with autism. We examined the extent to which pupillary contagion reflects autonomic nervous system reaction through pupil size change, heart rate and skin conductance response. Our second aim was to determine the association between arousal reaction to stimuli and degree of autistic traits. Results show that pupil contagion and concomitant heart rate change, but not skin conductance change, was evident when gaze was restricted to the eye region of face stimuli. A positive association was also observed between pupillary contagion and autistic traits when participants’ gaze was constrained to the eye region. Findings add to a broader understanding of the mechanisms underlying pupillary contagion and its association with autism.

Real-world uptake of an innovative pupil expander device for cataract surgery: Implementation lessons learnt.

Cataract surgery in the eyes, where the pupil does not dilate despite using eye drops, is fraught with vision-threatening complications. About 11 per cent of eyes undergoing cataract surgery have non-dilating, small pupils. The increasing prevalence of benign prostatic hyperplasia (BPH), hypertension, diabetes and medications used for the same are the contributing factors. The recent Food and Drug Administration (FDA) approval for the use of miotic agents in the treatment of presbyopia will lead to a further rise in the number of non-dilating pupils. While pharmacological agents and other methods have been used, mechanical pupil expander devices are the only fail safe option. However, available devices had a steep learning curve and limitations which made them difficult to use, unpredictable and unsafe. With its patented single plane, hexagonal, notches and flanges design, the US FDA registered B-HEX Pupil Expander (Med Invent Devices Pvt. Ltd., India) overcame these limitations and fulfilled an unmet need. The B-HEX is machinable, rapidly produced, consistent, easy to use, safe, and affordable. Despite such advantages, implementation hurdles have restricted its availability to healthcare systems worldwide. Peer acceptance has been steadily growing, with the B-HEX becoming the market leader in India, as evidenced by numerous publications, videos and papers presented at international conferences and comments from opinion leaders endorsing its use. However, impractical regulatory requirements and resource constraints remain a great impediment to the global distribution of this novel invention. This has denied many patients the benefits of a superior and more affordable option. Though value continues to be added to the B-HEX by maintaining a strong intellectual property portfolio with internationally granted Patents and Trademark, increasing its user base, and garnering support from key opinion leaders, only a collaboration with the right partner will help scale up the global reach and make it a leader in the global market.

Engineering for a clear image: a comparative focus on accommodation.

The eye requires the ability to focus images near and far and throughout evolution numerous mechanisms have developed to allow this accommodation. From primitive organisms which use a small pupil to effect pinhole camera optics without a lens through more complex eyes with a lens that is moved antero-posteriorly along the visual axis or the shape of which is changed, the eye has engineered numerous accommodative mechanisms. Human inventors have developed cameras with remarkable accommodative abilities but none match the remarkable focussing abilities of the four-eyed fish Anableps or the cormorant which similarly manages to focus above and below water, to give just two examples from the animal kingdom, perfectly adapted to their environments and behaviours.

A randomized control study on post-operative iris distortion following small-pupil cataract surgery using B-HEX pupil expander versus Malyugin ring

BackgroundThe aim of the study was to evaluate postoperative pupil distortion following small pupil cataract surgeries performed using B-HEX and Malyugin rings (MR). MethodsA randomized control trial was conducted from June 2020 to June 2023 at a tertiary eye-care hospital. The study consisted of 64 participants for cataract surgery with small pupil. There were two groups, one undergoing surgery with the use of B-HEX pupil expander and other with MR intraoperatively and the rest of the surgery was proceeded as per the convention. Areas of preoperative and postoperative images was calculated, put into an online software and pupil distortion was calculated in percentage. Two-tailed t-test was used to see the difference between the two groups. ResultsMean age at presentation was 70.5 ± 10.12 years. Most common cause for small pupil was tamsulosin therapy. Mean size of small-pupil was 3.0 ± 1.1 mm. With the application of two rings, mean pupillary area preoperatively was 4178.23 ± 1589.46 and postoperatively was 6100.44 ± 2658.28 following the use of MR, respectively and 30,002.93 ± 13,193.40 preoperatively and 37,648.26 ± 15,207.01 postoperatively following the use of B-Hex ring respectively. Comparing baseline area from pupillary area at 1-month follow-up, a significant increase was noted for both the rings. Also, MR caused significantly more pupillary distortion compared to B-HEX ring (p < 0.05). ConclusionMR causes significantly more pupillary distortion in the postoperative period compared to B-HEX ring. Though, both the rings cause pupillary distortion, these devices expand the surgical area adequately, ease the procedure, decrease risk of complications achieving good functional visual outcomes.

Comparison between two-hole-assisted phaco-chop and stop-and-chop techniques for nuclear disassembly in residents’ cataract surgery

Abstract PURPOSE: The purpose of this study was to evaluate the safety of the novel two-hole-assisted phaco-chop technique as a transition between stop-and-chop and direct-chop techniques and to compare its phacoemulsification parameters with the stop-and-chop technique. METHODS: A prospective quasi-experimental study was conducted at Al-Shifa Trust Eye Hospital, Rawalpindi, Pakistan. One hundred and three patients (103 eyes), aged 18 years and above, with nuclear sclerosis (NS)+2, NS +3, +4, cortical, and posterior subcapsular cataracts (WHO Cataract Grading Group) were included, whereas patients with uveitis, glaucoma, traumatic cataracts, small pupils, zonular weakness, lens subluxation, small palpebral fissures, soft cataracts (NS + 1), and posterior polar cataracts were excluded from the study. The stop-and-chop technique was performed in 58 (56.3%) patients, whereas the two-hole-assisted chop technique in the rest. Ultrasound time (UST), total surgical time, and volume of balanced salt solution (BSS) delivered were recorded. RESULTS: The mean age of the participants was 65.12 ± 8.85 years. The comparison of the two techniques revealed no statistically significant difference in the UST (P = 0.723), volume of BSS used (P = 0.102), and total surgery time (P = 0.517). However, a significant positive correlation between cataract grade and UST (Spearman’s r = 0.888, P &lt; 0.001), BSS volume delivered (Spearman’s r = 0.831, P &lt; 0.001), and surgery time (Spearman’s r = 0.846, P &lt; 0.001) was observed. Moreover, the UST comparison between cataract grades revealed a significant difference between the three groups (F = 185.09 P &lt; 0.001). P &lt; 0.05 was considered statistically significant. CONCLUSION: The two-hole-assisted phaco chop is a safe and efficient transitional technique between stop-and-chop and direct-chop techniques for nuclear disassembly in cataract surgery performed by resident surgeons. In addition, the phacoemulsification parameters of the two-hole-assisted chop technique are comparable with the stop-and-chop technique.

Midperipheral mini-capsulorhexis as an additional step for safe phacoemulsification in white intumescent cataracts.

The present article describes a novel surgical technique of a primary mini-capsulorhexis in midperiphery to minimize surgical complications in white intumescent cataracts. Patients with white mature cataracts with a convex anterior capsule or swollen lens fibers were selected. An initial puncture was made 3-4 mm away from the center, in the midperipheral anterior capsule, with a conventional cystitome. A mini-capsulorhexis (2-2.5 mm) was created. Loose cortical matter and fluidic contents were aspirated to reduce the intralenticular pressure. Two cuts were made at the margin of the mini-capsulorhexis, and an adequately sized secondary rhexis was completed, after which phacoemulsification was done. A circular curvilinear capsulorhexis was successfully achieved in all cases, including those with a small pupil. Rhexis could be completed in a patient where an initial extension occurred due to head movement. This refined technique aims to enhance the safety and precision of capsulorhexis in intumescent cataracts, thereby reducing the risk of complications such as the Argentinian flag sign. Further exploration and validation of this approach through clinical trials are warranted to establish its efficacy and safety profile.

The Impact of Back Optic Zone Design in Orthokeratology on Visual Performance.

To evaluate the visual performance in adolescents undergoing orthokeratology (OrthoK) treatment with two different optical zone diameters (OZDs). This randomized, double-masked, self-controlled prospective study was conducted at Tianjin Eye Hospital (Tianjin, China) in June 2022. Thirty-six eligible schoolchildren were enrolled and fitted with corneal refractive therapy lenses with two sizes of OZDs (5 mm [5OZ] and 6 mm [6OZ]). Each participant was randomized to wear the 5OZ in one eye and the 6OZ in the contralateral eye. Subjective visual quality was assessed using visual acuity, refraction, contrast sensitivity function, and visual symptoms, and the objective optical quality was assessed using ocular higher order aberrations (HOAs) and modulation transfer function (MTF). Thirty-five myopic children completed a 1-month follow-up visit. The 5OZ lens induced significantly smaller treatment zone diameters than the 6OZ lens (P < 0.001). Subjective visual quality did not differ significantly between the two groups. Compared to baseline, aberrations of Z40, coma-like, spherical-like, and total HOAs in both groups increased significantly (P < 0.05). For the 3-mm pupils, spherical aberration in the 5OZ group was significantly higher than that in the 6OZ group (P < 0.05). The MTF value of the 6OZ group was significantly higher than that of 5OZ group for 0.3 and 1.5 cycles per degree for the 3-mm pupils (P = 0.006 and P = 0.026, respectively). However, HOAs or MTF did not differ significantly between the two groups for the 5-mm pupils. The difference induced by varying OZD was significant only in the smaller pupil condition. The selection of OZD in OrthoK designs in real-world patient management should be done while considering individual pupil size. This study revealed that the objective visual quality of small OZD lenses was only slightly affected for the small pupil size.

Ophthalmology Residents' Experience in Cataract Surgery: Preoperative Risk Factors, Intraoperative Complications, and Surgical Outcomes.

This retrospective study explores the connection between preoperative patient risk factors, the experience of ophthalmology residents, and the outcomes of cataract surgeries performed at Hadassah Medical Center. It is hypothesized that with increased experience, residents may demonstrate greater proficiency in handling surgeries on higher-risk patients, potentially leading to improved surgical outcomes overall. Data were examined from 691 consecutive cataract surgeries in 590 patients, conducted by ophthalmology residents at Hadassah Medical Center (January 2018 to February 2022). Demographics, surgeon experience, preoperative cataract risk assessment score, and pre- and postoperative corrected distance visual acuity (CDVA) were analyzed. The risk score was based on cataract density, previous vitrectomy, presence of phacodonesis, small pupil, extreme axial length (> 30mm or < 21.5mm) or abnormal axial length (26-30mm), shallow anterior chamber (< 2.5mm), poor patient cooperation, oral alpha-1 blocker use, diabetic retinopathy (DR), Fuchs endothelial dystrophy, and having one functioning eye. This study focused on the correlation of risk scores with residents' surgical experience and surgical outcomes. As residents gained experience, surgeries on patients with at least one risk factor increased from 54% (first year) to 75% (second year; p < 0.001) and fluctuated between 75%, 82%, and 77% (third, fourth, and fifth years, respectively), with initial preoperative CDVA declining progressively. Despite handling more complex cases over time, the percentage of intraoperative complications per patient decreased with each year of residents' experience (17%, 13%, 11%, 17%, 6%; respectively). Patients without any risk factor had higher postoperative CDVA than those with one or more risk factors (mean ± standard deviation [SD] in logMAR, 0.16 ± 0.26 vs. 0.27 ± 0.35; p < 0.001) and a higher percentage of CDVA improvement (63% vs. 57%, p = 0.016). The use of a preoperative risk assessment scoring system to allocate surgeries to residents at varying experience levels may reduce the risk for surgical complications, thereby ensuring patient safety and providing residents with a gradual learning experience.

Corneal morphology following use of Malyugin versus B-hex pupil expansion rings in small pupil phacoemulsification

Aim: The aim of the study is to evaluate changes in corneal parameters following the use of the Malyugin ring (MR) and B-Hex ring (BhR) in small pupil phacoemulsification. Methods: A prospective cross-sectional study. 51 eyes with small pupil underwent phacoemulsification with the use of MR and BhR as pupil expansion techniques. Best-corrected visual acuity (BCVA), endothelial cell counts density (ECD), coefficient-of-variation (CV), hexagonality, central corneal thickness (CCT), and intraocular pressure (IOP) were recorded on preoperative day and postoperative day 1 and day 30. Results: Mean age at presentation was 70.9 ± 4.1 years. The most common cause for small pupils was alpha-blockers used in benign prostate hypertrophy, followed by diabetes mellitus and pseudo-exfoliation syndrome. Mean preoperative BCVA (3/60–6/12), IOP (17.12 ± 2.81 mmHg), CCT (530.96 ± 44.47 μ), ECD (2347.96 ± 298.09 cells/mm2), 6A (48.92% ± 6.34%) and CV (39.50 ± 3.49) changed to BCVA (6/9–6/6), IOP (18.69 ± 1.91 mm of Hg), CCT (536.04 ± 37.61 μ), endothelial cell count (2201.15 ± 276.75 cells/mm2), 6A (45.12% ±4.99%), and CV (37.57 ± 3.37) at day 30 postoperatively after use of MR. Similarly, mean preoperative BCVA (3/60–6/12), IOP (16.40 ± 2.42 mmHg), CCT (532.40 ± 36.14 μ), ECD (2433.68 ± 162.01 cells/mm2), 6A (48.84% ± 3.73%), and CV (39.36 ± 3.915) changed to BCVA (6/9–6/6), IOP (17.68 ± 2.75 mmHg), CCT (546.88 ± 31.25 μ), ECD (2322.08 ± 167.97 cells/mm2), 6A (46.36% ± 3.25%) and CV (38.96 ± 4.43) at day 30 post-operatively after use of BhR. The average change was clinically insignificant at day 30. Conclusion: MR and BhRs are safe pupil expansion devices and the corneal parameters are in the acceptable range of any routine phacoemulsification for senile cataracts. Nevertheless, B-hR shows relatively less alteration in corneal parameters, when compared to MR.

Research on the tilt-to-length coupling noise suppression method inside the gravitational wave detection telescope.

As an integral component of the laser interferometry measurement system, the tilt-to-length (TTL) coupling noise inside the telescope stands out as a critical noise factor that requires meticulous consideration. In the TianQin project, the non-geometric TTL-coupled noise inside the telescope should be less than 0.22 pm/Hz1/2. Additionally, the wavefront aberration RMS at the small pupil of the telescope needs to be better than 0.0065 λ. These requirements set for the telescope are exceptionally stringent. To address this challenge, this study aims to relax the wavefront aberration requirements by mitigating non-geometric TTL coupling noise, while ensuring the non-geometric TTL coupling noise remains below 0.22 pm/Hz1/2. By controlling the coupling aberration proportion, the wavefront aberration RMS at the small pupil of the telescope can be relaxed to 0.014 λ. Alternatively, optimizing the Gaussian beam waist radius can relax the wavefront aberration RMS to 0.016 λ. By simultaneously utilizing two optimization methods, the wavefront aberration at the small pupil of the telescope can be reduced to 0.033 λ, resulting in an impressive success rate of 91.15% in meeting the noise requirements.

ASSESSMENT OF VISUAL ACUITY AND COMPLICATIONS POST CATARACT SURGERY IN PATIENTS WITH UVEITIS IN TERTIARY CARE HOSPITAL

Aim and Objectives Aim:To study the visual acuity and operative complications after cataract surgery in patients with uveitis in tertiary care hospital Objectives: 1.To study factors affecting visual acuity. 2.To study surgical complications post cataract surgery in uveitis patients. Materials and Methods:A total of 18 patients were taken, data was collected from all the selected patients using a structured proforma meeting the objectives of the study. • Inclusion Criteria:1.All complicated cataract patients attending ophthalmology OPD 2.A quite eye (without inflammation) for atleast 3 months • Exclusion Criteria: 1.Cataract due to causes other than uveitis 2.Patients with posterior segment pathology Patients were scheduled for follow up on post op day 1, day 3 , day 7 , day 15, day 30, day 60, day 90. Results: The prevalance was more common in males compared to females. Out of 18 patients, 14 (77%) underwent SICS with PCIOL implantation and 4 (22%) underwent phacoemulsification with PCIOL. Intra-operative complications were noted as small non-dilating pupil, peripheral anterior synechiae, pupillary membrane, incomplete capsulorhexis, iris prolapse. In 7 (38%) patients sphincterectomy was done and in 4 (22%) patients stretch pupilloplasty was done. Immediate post-op complications that were noted were anterior chamber reaction and pigment dispersion. Late post-op complications that were noted were posterior capsular opacification Dense posterior synechiae were encountered in 12 (66%) patients and excessive conjunctival bleeding in 6(33%) patients. There was improvement in visual outcomes as follows 8 patients had 6/6 vision, 6 patients had 6/18 vision where as remaining 4 patients had 6/36 vision due to early development of posterior capsular opacification. Conclusion: Cataract development is a very common occurrence in any form of anterior and intermediate uveitis because of chronic intraocular inflammation, long term use of corticosteroids. Reported incidence of cataract in uveitic patients is about 25% in juvenile rheumatoid arthritis and 75% in chronic anterior uveitis. It is possible to achieve successful visual outcomes following cataract surgery in uveitis by proper management of pre-operative inflammation and close post-operative observation. Management of uveitic cataract requires careful case selection, proper timing of surgery, and close monitoring with appropriate handling of complications that may occur.

Comparison of pupil expansion devices in small pupil phacoemulsification.

To study the outcomes of phacoemulsification in small pupils (≤4 mm) using pupil expansion devices at a tertiary eye care center in South India. The study design is prospective, randomized, comparative, and interventional. Mechanical pupil dilatation with iris retractors (group I), B-HEX ring (group II), and Gupta ring (group III) was compared with respect to pupil size achieved (intraoperative), total surgical time, device addition time, complications, endothelial cell loss, and postoperative best corrected visual acuity. Among 36 participants (12 in each group), the mean pupil size, total surgical time, and device addition time were maximum with iris retractors. Intraoperatively, sphincter tear was seen in two eyes in the iris retractors group and one eye in the Gupta ring group. In the B-HEX ring group, only two flanges of the ring could be engaged in two participants, one patient had iris bleeding (during stretching of the iris), and one patient had anterior lens capsular tear. Among all three groups, there was no statistically significant difference in best corrected visual acuity (BCVA), endothelial cell count, and coefficient of variation obtained in the preoperative period, postoperative Day 7 and Day 30, respectively. In our study, in more than 50% of cases, the cause of small pupil was idiopathic/senile. Among nonidiopathic causes, PXF was the most common association. Although iris retractors are cost-effective and give maximum intraoperative dilatation, there is a need of four additional side ports to be made, thus increasing the total surgical time and device addition time. On the other hand, B-HEX and Gupta ring provide comparable intraoperative dilation and device addition time and also have comparable postoperative outcomes in terms of postoperative pupil size and complications.

Successful Management of Cataract in Patient With Long Anterior Zonules and Small Pupil :A Rare Case

Introduction : Long anterior zonules (LAZ) are rare disease with prevalence was 1–2%, characterized by zonular fibers that extend centrally leading to a small zonule-free zone (ZFZ), which raises the risk of complications during zonular cutting while continuous curvilinear capsulorhexis (CCC). This leads to two options whether to perform phacoemulsification through a small CCC within the small ZFZ or an adequately sized CCC. The objective of this study was to report challenging management of phacoemulsification surgery with LAZ eyes with small pupil&#x0D; Case Illustration : A 62 y.o female had visual acuity(VA) 0.7(logMAR) due to corticonuclear cataract in left eye. She had history complicated cataract surgery with secondary sulcus fixated IOL in her fellow eye. The IOP was normal, no phacodenesis and pseudoexfoliative material observed in left eye. The posterior segment was normal. The left eye observed otherwise normal in initial examination. Intraoperatively, after viscomidriasis technique the ZFZ identified in the area of 2.0-2.5 mm from central. Five millimeter CCC can be achieved in the central area and phacoemulsification with the help of CTR (Capsular Tension Ring) safely performed and one piece IOL was implanted in the bag.&#x0D; Discussion : On the first postoperative day, VA was improves to 0.4(logMAR), IOL central and clear corneal with minimal inflammation. One week after surgery, the VA 0.3(logMAR) and no sign of IOL decenteration.&#x0D; Conclusion : Phacoemulsification in eyes with LAZs can be safely performed with CTR through an adequately sized CCC without significant complications. A combination of early recognising high-risk eye, proficient skills, and surgical instruments can improve outcome.