Reduction In Astigmatism Research Articles

One-year long-term clinical outcomes following diffractive trifocal toric intraocular lens implantation: retrospective observational case series study.

Trifocal intraocular lens (IOL) provides three foci for the external light to the eye. The reduction of corneal astigmatism makes three foci to clearly focus on the fovea. This study aimed to evaluate one-year clinical outcomes for near, intermediate, and far distance visual acuity and satisfaction in patients implanted with diffractive trifocal toric IOLs. This retrospective observational case series study was based on the medical records of patients who undergone uncomplicated cataract surgery with implantation of a trifocal toric IOL (POD AY 26P F-T FineVision Toric; PhysIOL SA, Liège, Belgium). Eyes with corneal astigmatism greater than 1.00 diopters were included. Postoperative evaluations included uncorrected near, intermediate, and distance and corrected distance visual acuity; defocus curves; and contrast sensitivity measured at both three months and one-year postoperatively. Subjective satisfaction was evaluated based on three kinds of questionnaires for spectacle dependence, quality of vision, and overall satisfaction. Postoperative uncorrected distance visual acuity and that at 33, 43, 50, 60, and 80 cm at one-year were 0.07±0.08, 0.22±0.11, 0.17±0.11, 0.14±0.10, 0.14±0.10, and 0.15±0.10 logarithm of the minimal angle of resolution (logMAR), respectively. A smooth range of good visual acuity was found on defocus curve. Subjective scores for spectacle dependence, quality of vision, and subjective satisfaction showed no significant differences between three months and one-year postoperatively. The mean amount of IOL axis rotation was 2.14±1.72° (range: 0.2-5.1°) at one-year postoperatively. Implantation of a diffractive trifocal toric IOL for cataract, presbyopia, and astigmatism correction provided good refractive and visual outcomes, relatively smooth range of intermediate vision, and high levels of visual quality and patient satisfaction until one-year after surgery.

Study of changes in pre-existing against-the-rule astigmatism after temporal manual small-incision cataract surgery using frown, straight, and smile incisions.

To assess the change in the amount of astigmatism caused by frown, straight, and smile incision in patients with pre-existing against-the-rule (ATR) astigmatism of more than and equal to 1 diopter. This is a prospective, comparative study conducted over 18 months on 60 patients. Twenty patients were allocated to each incision using simple random sampling. Demographic details, best-corrected visual acuity (BCVA), intraocular pressure (IOP), anterior and posterior segment evaluation, and A-scan were done. An average of three measurements of K horizontal (Khavg), K vertical (Kvavg), and difference between the two (Khavg - Kvavg) were taken using manual keratometry. All surgeries were performed by a single surgeon. All the data analyses were performed by using IBM Statistical Package for the Social Sciences (SPSS) version 20 software. Frequency distribution and cross tabulation were performed to prepare the tables. In frown incision, Khavg - Kvavg was significantly decreased on day 45 from the preoperative value (P < 0.001), followed by straight incision (P < 0.001), and smile incision (P < 0.001). Maximum decrease was observed in frown incision (49.15%) followed by straight (37.75%) and smile (28.57%) incisions. Our results are consistent with reduction of pre-existing ATR astigmatism with temporal incisions, and frown incision seems to be the best approach.

Коррекция дислокации гаптического элемента торической ИОЛ у пациента после факоэмульсификации и склеральной фиксации модифицированного капсульного кольца при синдроме Марфана

Purpose. To propose a surgical technic for correcting the dislocation of the haptic element of the toric intraocular lens (IOL) in a patient after phacoemulsification and scleral fixation of the modified capsular ring in Marfan syndrome (MS). Material and methods. To report a case about dislocation one of the haptic elements of a toric IOL out of the capsular bag as a result of contraction of the capsular bag in a patient with MS in the presence of sutured modified capsular tension ring. The patient underwent a comprehensive ophthalmological examination, including refractometry, eye biometry, ophthalmoscopy, fundus examination for medical mydriasis, keratotopography, computed tomography of the cornea, and surgical treatment. Results. Removal and peeling of fibrous tissue, located under the anterior capsule with a reposition of the haptic of toric IOL resulted in significant astigmatism reduction and visual functions improvement. Conclusion. The proposed surgical technic for dissection of the anterior capsule fibrosis and reposition of the IOL haptics is effective for restoring the anatomically correct position of the IOL, and also allows to obtain a good functional result. To the best of our knowledge, successful treatment of late postoperative residual astigmatism with IOL tilt under conditions of transscleral fixed modified capsular tension ring (M-CTR) with haptic dislocation from the capsular bag and the presence of contraction capsular syndrome in SM has not been previously described in the literature. Key words: Marfan syndrome, capsule contraction syndrome, modified capsular tension ring, phacoemulsification, toric IOL result. To the best of our knowledge, successful treatment of late postoperative residual astigmatism with IOL tilt under conditions of transscleral fixed modified capsular tension ring (M-CTR) with haptic dislocation from the capsular bag and the presence of contraction capsular syndrome in SM has not been previously described in the literature.

Repeated Femtosecond Laser-Assisted Astigmatic Keratotomies in Post-Keratoplasty Eyes

Visual rehabilitation after a keratoplasty is often compromised due to high amounts of residual astigmatism. Femtosecond laser-assisted astigmatic keratotomy (FLAK) is gaining popularity in decreasing this astigmatism. Though one set of two incisions suffices in most cases, sometimes the treatment proves insufficient and additional treatment is required. This case series evaluates the outcomes in patients who underwent two consecutive FLAK sets to correct post-keratoplasty residual astigmatism. All repeated FLAK cases performed on post-keratoplasty eyes were reviewed in a high-volume clinic as a non-comparative retrospective case series. The data extracted include the procedure parameters, time between procedures, refraction including sphere, astigmatism, spherical equivalent (SE), and uncorrected and best-spectacle-corrected distance visual acuity (UDVA, BSDVA, respectively). Eleven eyes of eleven patients aged 25.5 ± 10 treated with more than one FLAK procedure were identified. The average follow-up time was 6 months after the first FLAK and 24 ± 10 months after the second. The second FLAK was performed six months after the first. The preoperative mean astigmatism was −9.59 ± 2.36 D. At the final follow-up, the mean astigmatism decreased to −5.38 ± 1.79 D (p = 0.001). Repeated FLAK procedures achieved a significant and stable reduction of astigmatism in post-keratoplasty eyes. This procedure shows safety and effectivity in these complex eyes and may prevent the need for a further keratoplasty.

Changes in Astigmatism and Visual Acuity after Pterygium Excision in the Ashanti Region of Ghana

Background: Pterygium is a conjunctival subepithelial fibrovascular growth commonly occurring in the inter-palpebral conjunctiva nasally or temporally. It tends to grow over the cornea, leading to visual impairment due to various factors, including astigmatism.
 Methods: This was a prospective, multi-centered, hospital-based, interventional study carried out within 12 months in three eye centers in the Ashanti region of Ghana. One hundred eyes of 100 adults (≥18 years) with primary pterygia were recruited. Operated eyes had measurements of uncorrected visual acuity (UVA), aided visual acuity (AVA), and keratometry readings (K-readings) before pterygium excision with conjunctival autograft (CAG), 2 weeks after surgery, and 6 weeks after surgery.
 Results: The mean age of patients was 47.1±11.5 years. The mean pre-operative astigmatism was 5.0±5.9 D. The mean astigmatism values at 2 and 6 weeks post-operatively were 1.7±1.5 and 1.3±1.0 D, respectively. Eighty-nine eyes had AVA ≥6/12 (0.11 mean logMAR) before surgery, whereas 97 eyes had AVA ≥6/12 (0.02 mean logMAR) 6 weeks after surgery, and the increase was statistically significant.
 Conclusion: Pterygia excision with CAG leads to an approximately fourfold reduction in mean pterygium-induced astigmatism by 6 weeks after surgery.

Analyse vectorielle de la correction de l’astigmatisme par incisions arciformes au laser femtoseconde dans les astigmatismes géants post-kératoplastie transfixiante

To study the results of femtosecond laser-assisted arcuate keratotomy in extreme astigmatism after penetrating keratoplasty, using a Ziemer LDVZ6 with a modified Lindstrom nomogram. Case series, retrospective study. Consecutive eyes that underwent femtosecond laser-assisted arcuate keratotomy between 2014 and 2019 in the Nantes University Hospital for extreme astigmatism after penetrating keratoplasty were included. Twenty-four eyes of 24 patients were included. The mean age was 53.3±12.2 years at the time of the arcuate keratotomies. Indications for penetrating keratoplasty were keratoconus in 66.7% of cases, herpes keratitis in 16.7% of cases, and corneal dystrophy in 16.7% of cases. The mean initial best corrected visual acuity was 0.36±0.23 logMar versus 0.26±0.15 logMar at the 3-month postoperative visit (P=0.04). At the postoperative visit, 54% (13/24) of eyes had improved best corrected visual acuity (BCVA), and 25% had no change in BCVA, with a mean cylinder reduction of 3.3 diopters. The mean preoperative topographic cylinder was 9.5±3.2 diopters versus 6.2±2.8 diopters postoperatively (absolute values; P<0.001), i.e. a 34.7% reduction in astigmatism. At the 3-month postoperative visit, 20.8% of eyes (5/24) had topographic astigmatism less than 3 diopters with a mean astigmatism reduction of 97±55% (range: 17; 201) using the Alpins method. No suppurative keratitis or endophthalmitis were observed. Twenty-one percent of patients underwent a second arcuate keratotomy after 3 to 6 months due to insufficient refractive results. Development of new nomograms designed for extreme astigmatism after penetrating keratoplasty would enhance the precision and reproducibility of femtosecond laser-assisted arcuate keratotomy in these cases.

Factors associated with corneal astigmatism change after ptosis surgery.

To evaluate the predictive factors of postoperative corneal astigmatism change in ptosis patients who underwent ptosis surgical repair. Patients who underwent levator resection at Oculoplastic service of the Department of Ophthalmology, Naresuan University Hospital, Thailand between September 2017 and August 2019 were retrospectively evaluated. Changes in degree and axis of corneal astigmatism after ptosis surgery were compared based on patient factors consisting of age at operation, sex, preoperative margin-reflex distance (MRD) 1, and preoperative degree and axis of corneal astigmatism. Forty-two eyes of 28 patients were included in the study. Wilcoxon signed ranks test showed a significant postoperative corneal astigmatism change only in a subgroup of eyes with preoperative astigmatism of ≥1.5 diopters (D; P=0.006). Furthermore, 72.2% (13/18) of the eyes with preoperative astigmatism of ≥1.5 D showed a reduction of astigmatism after eyelid surgery, with the mean astigmatic change of 0.65 D. Majority of preoperative eyes demonstrated with-the-rule astigmatism pattern (45.2%), of which 57.9% showed a reduced degree of astigmatism. In patients undergoing ptosis surgery, the data demonstrate for the first time the association between postoperative corneal astigmatism change and a preoperative corneal astigmatism of ≥1.5 D. Thus, we encourage considering severity of corneal astigmatism prior to cataract or refractive surgery planning in ptosis patients, especially with toric-intraocular lens, to avoid the possibility of calculation error.

Peripheral Refraction and Contrast Detection Sensitivity in Pseudophakic Patients Implanted With a New Meniscus Intraocular Lens

To evaluate peripheral refraction and contrast detection sensitivity in pseudophakic patients implanted with a new type of inverted meniscus intraocular lens (IOL) (Art25; Voptica SL) that was designed to provide better peripheral optics. One month after cataract surgery, in 87 eyes implanted with the Art25 IOL, peripheral contrast detection sensitivity was measured psychophysically at 40° visual angle, both horizontally and vertically, and compared with a control group of 51 eyes implanted with standard biconvex IOLs. Thirty-one eyes with the Art25 IOL and 28 eyes from the control group were randomly selected to also measure peripheral refraction using a scanning Hartmann-Shack wavefront sensor along 80° in the horizontal meridian. Most patients achieved emmetropia and good visual acuity, and no significant adverse events were observed after cataract surgery with Art25 IOLs. Peripheral contrast detection sensitivity was significantly better (P < .01) in the group with the Art25 IOL in both directions (7.78 ± 3.24 vs 5.74 ± 2.60 vertical, 10.98 ± 5.09 vs 7.47 ± 3.96 horizontal), which was in agreement with the optical quality improvement in the periphery due to a reduction of defocus (1.97 and 1.21 diopters [D] at 40° temporal and nasal sides) and astigmatism (1.17 and 0.37 D at 40° temporal and nasal sides) that was statistically significant (P < .01) from 20° of eccentricity. Patients implanted with a new inverted meniscus IOL present a reduced amount of peripheral defocus and astigmatism compared to patients implanted with standard biconvex IOLs. This improvement in optical quality leads to better contrast detection sensitivity measured at 40° of eccentricity. [J Refract Surg. 2022;38(4):229-234.].

Femtosecond laser-assisted cataract surgery after corneal refractive surgery

Cataract is the leading cause of blindness worldwide, and advanced cataract techniques such as femtosecond laser-assisted cataract surgery (FLACS) have been commercially available. Corneal refractive surgery (CRS) is one of the most popular surgeries for the correction of refractive errors. CRS changes the cornea not only anatomically but also pathophysiologically. However, there has been no clinical research analyzing the refractive and safety outcomes of FLACS after CRS. The aim of this retrospective chart review and comparative study is to evaluate the effect and safety of FLACS after CRS comparing with conventional PCS. Participants with a previous CRS history who underwent FLACS or conventional PCS were included in this study. The visual outcomes and the refractive outcomes including refractive, corneal, and ocular residual astigmatism were compared. The safety outcomes were then studied intraoperatively and postoperatively. A total of 102 patients with age-related cataract were enrolled. At 3 months postoperatively, UCVA, BCVA, and predictive error were not significantly different between the FLACS and conventional PCS groups. Reduction of refractive astigmatism was higher in FLACS. Postoperative ORA was significant lower in FLACS. Reduction of ORA was higher in FLACS. The intraoperative and postoperative complications were also not significantly different between the two groups. FLACS could effectively change refractive astigmatism and ORA; without more complications than conventional PCS. FLACS’ competitive edge in postoperative ORA may provide better visual quality than conventional PCS in patients with a previous history of CRS.

Hemidivisional vector planning to reduce and regularize irregular astigmatism by laser treatment

PurposeTo demonstrate how hemidivisional vector planning of refractive laser treatments of astigmatism can be used to directly address idiopathic corneal irregular astigmatism that has an asymmetrical, non-orthogonal bow tie topography appearance.DesignCase study.MethodsThe cornea is conceptually divided into two hemidivisions along the flat meridian of the corneal topographic astigmatism (CorT), which means that each hemidivision will approximately correspond to one lobe of the asymmetric, non-orthogonal topographic bow tie. An astigmatism reduction treatment can then be planned separately for each hemidivision using the vector planning technique, based on both its two hemidivisional CorT measures and common manifest refractive cylinder. The remaining irregularity is then regularized, and the junctional zone smoothed across the flat meridian. The final intended treatment thus combines hemidivisional astigmatism reduction and regularization of the corneal astigmatism and spherical refractive error in one treatment application. This could be applied to LASIK, PRK, SMILE, and Transepithelial PRK procedures using Designer Cornea® software.ResultsA theoretical treatment profile is derived from an actual example of a cornea with idiopathic asymmetric non-orthogonal astigmatism. The three steps of the derivation are as follows: (i) astigmatism reduction through the use of the vector planning technique; (ii) regularization, and (iii) smoothing across the hemidivisional midline.ConclusionsHemidivisional vector planning treatments could potentially both reduce and regularize asymmetric non-orthogonal astigmatism. These treatments can be systematically customized to account for qualitative and quantitative differences between the two corneal hemidivisions at the same time as correction of coexistent myopia or hyperopia.

Do limbal relaxing incisions during cataract surgery still have a role?

BackgroundThough Limbal Relaxing Incisions (LRI) were used widely to correct pre-existing corneal astigmatism during cataract surgery, they have been replaced recently with the more expensive methods like the use of toric Intra Ocular Lenses (IOL) and femtosecond during cataract surgery. We conducted our study to re-evaluate the role of (LRI) in correcting pre-existing moderate corneal astigmatism during cataract surgery in settings where other options are neither available nor affordable.MethodsRetrospective analysis of all consecutive cases of LRI performed by a single surgeon at the time of cataract surgery to correct moderate corneal astigmatism (1.5-3D) in a community hospital over a period of 6 months. Corneal astigmatism, uncorrected distance visual acuity (UDVA) and best corrected distance visual acuity (CDVA) were recorded pre-operatively, 4 weeks and 3 months post-operatively. Data on age, intraocular lens (IOL) power, predictive refraction and post-operative spherical equivalent was also collected and analyzed. The number and position of LRI was determined based on the pre-existing corneal astigmatism using online calculator.Results29 eyes of 25 patients with the mean age of 73.6 years (range: 46 to 90 years) and corneal astigmatism between 1.5 to 3D were included. Statistically significant reduction in the mean corneal astigmatism was recorded from 2.05 ± 0.45D preoperatively to 0.85 ± 0.56D postoperatively (P < 0.0001). All eyes showed reduction in astigmatism; 83% of eyes had < 1.0D post-operatively and 66% of eyes had < 0.75D. UDVA of 6/9 or better was recorded in 80% of eyes post-operatively (CDVA of 6/9 or better in 100%). The spherical equivalent was within 1.0D of the predictive refraction postoperatively in nearly all eyes (97%) and within 0.5D in 86% of the eyes. There were no peri-operative or post-operative complications were recorded in any case.ConclusionCombining LRI and cataract surgery to address moderate degrees of corneal astigmatism is a safe, reliable and predictable option especially in areas where more expensive methods such as toric IOL or excimer laser are not available or affordable. LRI has no significant effect on the spherical equivalent and is an excellent tool in reducing patient’s spectacle dependence.

Outcomes of cataract surgery with toric intraocular lens implantation after keratoplasty.

To evaluate the efficacy and predictability of cataract extraction with toric intraocular lens (IOL) implantation after deep anterior lamellar keratoplasty (DALK) or mushroom penetrating keratoplasty (PK). Villa Igea Hospital, Forlì, Italy. Prospective case series. Toric IOL implantation was offered to patients with cataract, corneal astigmatism >1.5 diopters (D) and regular central corneal topography after complete suture removal. Phacoemulsification was performed through a 2.4 mm scleral tunnel and an enVista monofocal toric MX60T or Eyecryl monofocal toric IOL was inserted in the capsular bag. Main outcome measures were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, total prediction error, and IOL misalignment. 37 consecutive patients who had previously undergone either DALK (n = 27, 73%) or 2-piece mushroom PK (n = 10, 27%) were included. All patients completed the 6-month follow-up. The mean toric IOL power was 5.3 ± 1.1 D. Both UDVA and CDVA significantly improved (from 1.02 ± 0.27 to 0.46 ± 0.31 logMAR and from 0.65 ± 0.27 to 0.11 ± 0.12 logMAR, respectively; P < .001). 20 eyes (54%) reached UDVA ≥20/40, whereas 35 eyes (95%) reached a CDVA ≥20/40. Final refractive astigmatism was 0.93 ± 0.87 D, with 35 eyes (95%) within 2 D. Prediction error was ≤1 D in 18 eyes (49%). Absolute IOL misalignment was 3.3 ± 3.5 degrees. Toric IOL implantation in postkeratoplasty eyes allowed reduction of refractive astigmatism to predictably low levels with concomitant improved visual outcomes.

Effect of Pterygium Removal Combined with Conjunctival Autograft on Corneal Parameters in Swept-Source Imaging.

Background: Both pterygium ingrowth and excision determine alterations in corneal topography. The aim of this study was to evaluate the influence of pterygium removal combined with conjunctival autografts in addition to the use of human fibrin tissue glue on changes in corneal parameters as measured by 3-D swept-source anterior segment optical coherence tomography (AS-OCT) imaging. Methods: Sixteen eyes (16 patients) with pterygium that qualified for surgical treatment were enrolled in this study. Eye examination, slit lamp, and 3-D AS-OCT (CASIA 2) assessment were performed before the surgery and 7 days, 1 month, and 6 months after pterygium excision. Topographic parameters of both anterior and posterior surfaces of the cornea were analysed at each follow-up visit. Results: The gradual decrease in total astigmatism power from preoperative median 2.75 (6.15) D to 1.2 (1.1) D at 6-month follow-up (p = 0.034) was noted from the day 7 visit. Values were strongly influenced by variations of anterior cornea astigmatism. In contrast, a gradual total HOA reduction at the 1-month (from median 0.79 (1.3) D to 0.44 (0.27) D; p = 0.038) and at 6-month visits (0.25 (0.09); p = 0.001) was observed. Similarly, values were strongly influenced by variations of the anterior. Additionally, total average keratometry values increased from preoperative 44.05 (2.25) D to 44.6 (1.9) (p = 0.043) 1 month after the surgery. Conclusions: Significant steepening of the anterior cornea and a reduction in both astigmatism and HOA were observed after pterygium excision. The anterior corneal surface was an essential component of the total postoperative corneal topography values. Three-dimensional swept-source AS-OCT imaging seems to be a valuable tool for monitoring both the progression of the disease and postoperative effects in pterygium eyes.

Comparing IOLM700 TK, Berdahl and Hardten astigmatism fix calculator and Barrett Rx formula in managing residual astigmatism due to toric intraocular lens misalignment.

Purpose:To compare the accuracy in astigmatism reduction by using IOLM 700 steep total keratometry (TK) axis, Berdahl and Hardten astigmatism fix, and Barrett Rx formula following misaligned toric intraocular lens (IOL).Methods:Ten patients with residual refractive astigmatism due to misalignment following toric IOL implantation were included in this retrospective study. They were analyzed at days 4, 7/8, and 10/11 following primary cataract surgery on the platform of Berdahl and Hardten astigmatism fix, Barrett Rx formula, and IOLM 700 to determine the optimum axis of repositioning, and underwent IOL realignment on the steep TK axis of IOLM 700 assisted by the Callisto eye. The final outcome parameters were subjective refraction and orientation of toric IOL assessed 22 ± 1 days following repositioning surgery. These parameters were fed in the Barrett Rx formula and its vector analysis graph was utilized to determine the predicted ideal axis with the least residual astigmatism and the estimated residual astigmatism if the toric IOL was realigned according to the axis suggested by Berdahl and Hardten astigmatism fix and Barrett Rx formula.Results:Realigning the toric IOL on IOLM 700 steep TK axis along with the Callisto eye reduces the residual refractive astigmatism significantly (P = 0.003) from 2.00 ± 0.78 D to 0.18 ± 0.12 D (90.5 ± 7.6%) in comparison to the estimated 0.57 ± 0.31 D (68.4 ± 21.9%) by Berdahl and Hardten astigmatism fix and 0.61 ± 0.33 D (66.4 ± 23.5%) by Barrett Rx formula.Conclusion:Realigning the misaligned toric IOL on the IOLM 700 steep TK axis gives a better reduction in the residual refractive astigmatism in comparison to Berdahl and Hardten astigmatism fix and Barrett Rx formula.

Treatment of corneal astigmatism by limbal relaxing incisions during phacoemulsification surgery

Background and aim The aim was to assess the effectiveness of limbal relaxing incisions (LRIs) in treatment of astigmatism in patients undergoing phacoemulsification surgeries. Patients and methods Forty-eight eyes of 48 patients suffering from senile cataracts of mean age 64.7±7.9 (range: 50–77) years, and mean corneal astigmatism 1.8±0.73 diopters (D) (range: 1.5–3.5 D) were included in this study. All LRIs were performed at the end of phacoemulsification. Corneal topography results were compared before surgeries and 2 and 6 months after surgeries. Results A statistically significant reduction in the mean corneal astigmatism was seen from 1.8±0.73 D (range: 1.50–3.50) preoperatively to 1.1±0.24 D (range: 0.5–1.7) and 1.4±0.52 D (range: 0.60–1.9) in the second and sixth postoperative months, respectively (P&lt;0.001). Surgical-induced astigmatism (the amount and axis of astigmatism change induced by surgery) was 0.90±0.48 at 2 months and 0.96±0.59 at 6 months. Correction index (calculated by determining the ratio of surgical-induced astigmatism/target-induced astigmatism) was 0.56±0.42 and 0.57±0.33 at 2 and 6 months, respectively. Index of success (ratio of topographic residual astigmatism and target-induced astigmatism) was measured to be 0.45±0.42 and 0.48±0.33 at months 2 and 6 correspondingly. Conclusion Combined LRI and phacoemulsification appears to be safe and fairly effective to correct mild-to-moderate corneal astigmatism. However, undercorrection is a common limitation that may be further managed by modified nomograms in future studies.

Study of visual outcome and complications following conjunctival autograft transplant in management of primary pterygium

Introduction: Pterygium is a common degenerative disease of the anterior segment of the eye characterized by a wedge-shaped fibrovascular dysplasia of the bulbar conjunctiva with a prevalence of 12%. Exact etiology is unknown; risk factors include, long term exposure of ultraviolet B rays, dust, wind, chemicals and air pollution. To minimize recurrence after the traditional bare sclera surgical technique, adjuvant therapies and modifications to the surgical technique are being adopted. Geographically, Vijayapura is located close to the equator with inherent risk of higher ultraviolet radiation exposures. Of late there is an upsurge in the number of patients with diagnosed with pterygium opting for surgical correction. Conjunctival autograft transplant is promising modification of bare sclera technique is associated with significant reduction in pterygium-induced astigmatism thereby improved visual acuity, decreased postoperative complications and decreased recurrence rates. Objective: To evaluate the visual outcome and complications following conjunctival autograft transplant in management of primary pterygium. Methods: The present study was conducted in the department of Ophthalmology, B.L.D.E. deemed to be university Shri B.M. Patil Medical College, Hospital and Research Centre, Vijayapura between October 2019 to April 2021. A total of 52 patients above 18 years with a diagnosis of primary pterygium were included in the study. Age, gender, occupation, side and severity of pterygium was recorded. Preoperative visual acuity and corresponding decimal pin whole equivalent was calculated for each patient. Upon surgery with conjunctival autograft under local anaesthesia, postoperatively, visual acuity, corresponding decimal pin hole equivalent and complications were evaluated at day 1, day 7 and day 30. Comparison of pre and postoperative data was done using appropriate statistical tests. Results: Mean age of patients was 54.38±10.70 years and 69.3% belonged to the age group of 50-70 years. Slight female predominance was noted with female to male ratio of 1.17:1. Most of the patients were farmers (48.5%) followed by housewives (23.1%). All patients had nasal pterygium prominently on the left side than right (61.5% vs 38.5%). 76.9% patients had grade 2 pterygia. Preoperatively, most patients had a visual acuity of 6/24 (25%), followed by 6/36 (19.2%) and 6/60 (17.3%). The mean decimal equivalent value was 0.35±0.21. Compared to preoperative visual acuity, significant improvement was seen at postoperative day 1 (p=0.000), postoperative day 7 (p=0.001) and at postoperative day 30 (p=0.001). Similarly significant increase in the decimal equivalent postoperatively (0.001) than preoperative values. Factors including age, gender, occupation, side and severity had significant association on the visual outcome based on visual acuity at all follow ups. Most common postoperative complication at day1 was subconjunctival haemorrhage (36%) is the common one followed by graft edema (36%) and graft retraction (13.5%). Resolution of complications was seen by day 30.Conclusion: Conjunctival autograft is a feasible and safe option in patients with primary pterygium with severe grading.

Residual astigmatism following cataract surgery

Objective: To determine the amount of residual astigmatism following cataract surgery.&#x0D; Materials and methods: A hospital based observational study was conducted in a tertiary eye hospital, Bangladesh during the period of July, 2013 to June, 2014. Patients was selected for the study who diagnosed as ARC with variable amount of astigmatism (1.5 to 3.5D), and excluded any other ocular pathology or history of previous ocular surgery. Phacoemulsification with PC Toric IOL implantation in all cases. Auto refracto-keratometer was done Preoperative and postoperatively for assessing the astigmatism. Main outcome measured were included preoperative uncorrected visual acuity, postoperative uncorrected visual acuity on 1stPOD, after 1 week and 1month, Preoperative keratometry, Preoperative astigmatism, Postoperative uncorrected keratometry on 1st POD, after 1 week and 1month, Postoperative uncorrected astigmatism on 1stPOD, after 1 week and 1month&#x0D; Results: 30 eyes of 28 patients were assessed in this study. Due to clear corneal incision during phacoemulsification, the steep meridian became flat significantly from pre-operative keratometry 44.329±1.473D (mean±SD) to 30thpost operative keratometry 43.971±1.431D (mean±SD) having p&lt;0.001. On the other-hand the flat meridian became steeper from pre-operative keratometry 42.225±1.471D (mean±SD) to 30thpost operative keratometry 42.421±1.501D (mean±SD) having p&lt;0.001. Preoperative mean astigmatism [Mean±SD] was 2.104±0.319D, after the first postoperative day, mean astigmatism decreased to 0.954±0.494D with p&lt;0.01, and finally after 1 Month there was significant reduction of pre-operative astigmatism to 0.583±0.413D with p&lt;0.0001. So, the mean pre-operative astigmatism decreased significantly in the successive post-operative days.&#x0D; Conclusion: Toric Intraocular lens implantation in phacoemulsification surgery can correct pre-existing corneal astigmatism significantly after one month of surgery.&#x0D; AKMMC J 2022; 13(1) : 42-46

Peripheral refraction of myopic eyes with spectacle lenses correction and lens free emmetropes during accommodation

PurposeTo measure axial and off-axis refraction patterns in myopic eyes with spectacle lenses correction and lens free emmetropes in young healthy subjects at different target distances from 2.00 m (0.50 D) to 0.20 m (5.00 D) in terms of sphere, astigmatism, and spherical equivalent refraction.MethodsRefraction was measured at the center, 20 and 40 degrees from the line of sight both nasally and temporally in 15 emmetropic and 25 myopic young healthy subjects with an open field, binocular, infrared autorefractor (Grand Seiko WAM-5500, Hiroshima, Japan). Fixation target was a Maltese cross set at 2.00, 0.50, 0.33 and 0.20 m from the corneal plane. Changes in off-axis refraction with accommodation level were normalized with respect to distance axial values and compared between myopic eyes with spectacle lenses correction and lens free emmetropes.ResultsOff-axis refraction in myopic eyes with spectacle lenses correction was significantly more myopic in the temporal retina compared to lens free emmetropes except for the closest target distance. Relative off-axis refractive error changed significantly with accommodation when compared to axial refraction particularly in the myopic group. This change in the negative direction was due to changes in the spherical component of refraction that became more myopic relative to the center at the 0.20 m distance as the J0 component of astigmatism was significantly reduced in both emmetropes and myopes for the closest target.ConclusionAccommodation to very near targets (up to 0.20 m) makes the off-axis refraction of myopes wearing their spectacle correction similar to that of lens free emmetropes. A significant reduction in off-axis astigmatism was also observed for the 0.20 m distance.

Fluid reservoir thickness and aberration relationship in keratoconic eyes with scleral lenses.

To investigate the effect of varying the fluid reservoir (FR) thickness of scleral lenses (SL) on corrected distance visual acuity (CDVA), contrast sensitivity (CS) and higher-order aberrations (HOAs) in keratoconic eyes. Forty eyes with keratoconus were fitted with a diagnostic Boston Sight SL having three different FR thicknesses. CDVA, CS and HOAs were measured before and after 30min of lens wear. An i-Trace aberrometer and anterior segment optical coherence tomography (AS-OCT) were used to measure HOAs and FR thickness, respectively. Statistically significant improvements in CDVA and CS were seen with different FR thickness lenses (p<0.01). Baseline CDVA (0.22±0.15) improved to 0.03±0.06, 0.04±0.07 and 0.07±0.08 with low, standard and high FR lenses, respectively. Post-hoc testing showed better CDVA with low (p=0.006) and standard FR (p=0.009) lenses compared to high FR lenses. Before lens wear, CS was 1.27±0.27, which improved to 1.67±0.11, 1.73±0.12 and 1.66±0.89 with low, standard and high FR lenses, respectively. Lenses with standard FR showed better CS compared with those having low (p=0.009) and high FRs (p<0.001). A statistically significant reduction of higher order-root mean square aberrations (HO-RMS), coma, spherical aberration, secondary astigmatism and trefoil were found with all FR thickness lenses compared to baseline (p<0.01). No significant difference was noted between lenses (p=0.01). All three lenses corrected almost equal amount of HOAs. A moderate positive correlation was observed between CDVA and HO-RMS (r=0.61, p<0.001) for low FR lenses. BostonSight SCLERALs were found to be very effective in improving vision, CS and reducing HOAs in keratoconus. Lenses with varying FR thickness showed equal effectiveness in visual performance and reducing HOAs. FR thickness should be considered an important factor to provide better vision and CS by minimising HOAs, as well as to maintain the normal physiology of eyes with keratoconus.

Refractive and keratometric outcomes of supervised novice surgeon-performed limbal relaxing incisions: 1-year results.

To report refractive and keratometric astigmatism outcomes of resident-performed limbal relaxing incisions (LRIs) during cataract surgery. Tertiary care academic teaching hospital. Retrospective case series. The length, location, and number of LRIs were determined preoperatively using an online calculator. Variables studied were preoperative keratometry and postoperative uncorrected and corrected distance visual acuity, refraction, and keratometry at 1-month, 3-month, and 12-month visits (POM1, POM3, and POM12, respectively). Subgroup analysis was performed on amount and type of astigmatism. The astigmatism double-angle plot tool and analysis of with-the-wound (WtW) and against-the-wound (AtW) changes were used to assess the effect of astigmatism correction at POM1, POM3, and POM12 visits. In 118 eyes, a higher percentage of eyes demonstrated refractive astigmatism 0.25 diopter (D) or less, 0.50 D or less, 0.75D or less, and 1.0 D or less at POM1 and POM12 (all P < .05) compared with preoperative keratometric astigmatism. Subgroup analysis showed improvement in all groups and types of astigmatism (P < .01). Patients achieved a statistically significant reduction of keratometric astigmatism at POM1, POM3, and POM12 (all P ≤ .0001) relative to baseline, and changes differed significantly based on the preoperative amount of astigmatism (all P ≤ .0001, with greater reductions associated with higher baseline astigmatism) but not by location of the steep meridian. There were significant WtW-AtW changes at POM1, POM3, and POM12. Regression of effect after 1 month was approximately 0.11 D. Resident-performed LRIs achieved effective and sustained reduction of both refractive and keratometric astigmatism regardless of meridian or magnitude of astigmatism for at least 1 year postoperatively.