Shveta Jindal Bali

Femtosecond laser cataract surgery: technology and clinical practice

The recent introduction of femtosecond lasers to cataract surgery has generated much interest among ophthalmologists around the world. Laser cataract surgery integrates high‐resolution anterior segment imaging systems with a femtosecond laser, allowing key steps of the procedure, including the primary and side‐port corneal incisions, the anterior capsulotomy and fragmentation of the lens nucleus, to be performed with computer‐guided laser precision. There is emerging evidence of reduced phacoemulsification time, better wound architecture and a more stable refractive result with femtosecond cataract surgery, as well as reports documenting an initial learning curve. This article will review the current state of technology and discuss our clinical experience.The recent introduction of femtosecond lasers to cataract surgery has generated much interest among ophthalmologists around the world. Laser cataract surgery integrates high-resolution anterior segment imaging systems with a femtosecond laser, allowing key steps of the procedure, including the primary and side-port corneal incisions, the anterior capsulotomy and fragmentation of the lens nucleus, to be performed with computer-guided laser precision. There is emerging evidence of reduced phacoemulsification time, better wound architecture and a more stable refractive result with femtosecond cataract surgery, as well as reports documenting an initial learning curve. This article will review the current state of technology and discuss our clinical experience.

Evaluating eye drop instillation technique in glaucoma patients.

AimTo evaluate the technique of eye drop instillation in glaucoma patients. MethodsSeventy patients with primary open-angle glaucoma or primary angle-closure glaucoma, self-administering topical antiglaucoma medications for at least 6 months were evaluated. All patients instilled a tear substitute in 1 eye using the same technique they used for instilling antiglaucoma medications at home. The parameters that were recorded included time taken to instill the first drop, number of eye drops instilled, drop contact location, any contact with the tip of the bottle, and closure of the eyelids or tear duct after drop instillation. ResultsThe mean age of the patients was 54.1±10.0 years. The mean time taken to instill the first drop was 14.8±3.7 seconds (range, 8.7 to 23.5 s). The mean number of drops squeezed from the bottle per instillation was 1.8±1.2 drops (range, 1 to 8 drops). In 22 patients (31.43%), the eye drops fell on the eyelids or cheek. Fifty-three patients (75.7%) touched the tip of the bottle to the globe or periocular tissue. Twenty patients (28.57%) closed eyes after instilling drops and 4 patients (5.7%) occluded the punctum. Only 6 patients (8.57%) were able to correctly instill the eye drops (squeeze out 1 drop and instill it into the conjunctival sac without bottle tip contact). ConclusionsNearly, 9 of 10 glaucoma patients were unable to instill eye drops correctly. This may be an important cause of unintentional noncompliance in glaucoma medical therapy.

Outcomes of Femtosecond Laser Cataract Surgery With a Diffractive Multifocal Intraocular Lens

PURPOSE To report the visual and refractive outcomes in an initial series of eyes undergoing femtosecond laser cataract surgery with implantation of a diffractive multi-focal intraocular lens (IOL). METHODS The first 61 consecutive eyes undergoing femtosecond laser cataract surgery and ReSTOR (Alcon Laboratories Inc) +3.00-diopter (D) add IOL implantation between May and July 2011 were enrolled in the study (LCS group). The control group consisted of a retrospective consecutive cohort of 29 eyes that underwent manual phacoemulsification cataract surgery and ReSTOR +3.00-D add IOL implantation (MCS group) between December 2010 and April 2011. Visual and refractive parameters were collected pre- and postoperatively at 1 and 3 months. RESULTS Mean postoperative spherical equivalent refraction was -0.01±0.35 D and -0.06±0.30 D in the LCS and MCS groups, respectively (P=.492). Mean absolute refractive prediction error (PE) was 0.26±0.25 D for the LCS group and 0.23±0.16 D for the MCS group (P=.489). Mean arithmetic refractive PE was 0.06±0.44 D and -0.02±0.30 D for the LCS and MCS groups, respectively (P=.388). No significant difference was noted in mean postoperative uncorrected distance visual acuity or uncorrected near visual acuity between groups. No eyes in either group had surgical complications or loss of corrected distance visual acuity in the follow-up period. CONCLUSIONS Mean spherical equivalent refraction and visual acuity of our initial group of patients undergoing laser cataract surgery are comparable to the manual phacoemulsification cohort for the AcrySof ReSTOR +3.00-D add IOL.

Femtosecond cataract surgery: transitioning to laser cataract.

Purpose of review The introduction of the femtosecond laser to the field of cataract surgery offers many potential benefits. The femtosecond laser is able to perform three important steps in cataract surgery: capsulotomy, lens fragmentation and corneal incisions. Although evidence in support of its efficacy is accumulating, there is a surgical learning curve that needs to be addressed. This review outlines key issues to consider when contemplating the transition to laser cataract surgery in clinical practice. Recent findings Laser cataract surgery has been shown to be associated with an initial learning curve. Femtosecond lasers produce a more accurate and precise anterior capsulotomy, improve intraocular lens centration and reduce intraocular lens tilt. Visual and refractive outcomes, although in a limited number of studies, have been shown to be at least as good as those of conventional phacoemulsification. The impact of reduced phacoemulsification energy on the corneal endothelium is still being investigated. Summary The automation of key steps by the use of femtosecond lasers in cataract surgery has several potential advantages. Emerging literature supports the transition from conventional phacoemulsification to the laser cataract surgery.

Femtosecond laser assisted cataract surgery in phacovitrectomy

IntroductionThe introduction of phacoemulsification in the 1990smade combined cataract surgery and vitrectomy a prac-tical procedure. Small and secure corneal incisions, in-creased anterior chamber stability, and implantation ofthe intraocular lens (IOL) in a stable capsular bagimproved the safety and visual outcomes of phacovitrec-tomy [1]. Refinements in vitrectomy instrumentation andtechniques, including sutureless pars plana incisions,have further improved the outcomes of this combinedprocedure [2].Femtosecond lasers have been used successfully to per-form some steps in cataract surgery. These have beenreported to produce superior corneal incisions, more preciseand stronger capsulotomies, and require reduced phacoe-mulsification power [3, 4]. We retrospectively report eightcases that underwent femtosecond laser-assisted cataract ex-traction in combination with sutureless 25-gauge vitrectomy.Materials and methodsEight cases with co-existing retinal pathologies (Table 1)andcataract underwent combined femtosecond laser-assistedcataract extraction and sutureless 25-gauge vitreoretinal sur-gery. Informed written consent was obtained for all subjects.Surgical techniqueThe patients were initially placed in the operating suiteunder the femtosecond laser (LenSx Lasers Inc., AlisoViejo, CA). Under topical anesthesia (tetracaine 1 % Min-ims), a disposable patient interface was docked to thepatient’s eye. Once adequate suction was achieved, the lasertreatment was performed after selection of capsulotomy andlens fragmentation patterns. The capsulotomy diameterwassetfor5mm;withananteriorandposterioroffsetof 150 μmand300μm, respectively. For the lens, themethod of fragmentation was“chop” (Fig. 1, laser phaco-fragmentation immediately prior to removal of the cata-ract). Anterior and posterior offsets were set at 500 and1,100 μm.Following the laser ablation, a retrobulbar block (1 %ropivacaine + hyaluronidase 75 μg/ml) was used. Patientswere then transferred to the operating room. Three trans-conjunctival angled pars plana incisions were performedusing 25-gauge trocar microcannula (Alcon, Fort Worth,TX, USA) in the inferotemporal, superotemporal, andsuper-onasal quadrants 3.5 mm from the limbus. The inferotem-poral microcannula was connected to an infusion line,whereas the other two microcannulae were closed withplugs. The infusion line was kept off to prevent posteriorvitreous pressure during phacoemulsification and IOL im-plantation. Phacoemulsification was completed through aclear corneal superotemporal incision and was followed byinsertion of an AcrySof SN60WF foldable IOL (Alcon, FortWorth, TX, USA). A near-complete vitrectomy includingvitreous base shaving was performed (Accurus, Alcon Lab-oratories, Inc., Fort Worth, TX, USA). Where indicated, the

Caregiver Burden Assessment in Primary Congenital Glaucoma

Purpose To assess the magnitude of caregiver burden and depression in primary caregivers of patients with primary congenital glaucoma. Methods Fifty-five primary caregivers of children diagnosed with primary congenital glaucoma were evaluated. The magnitude of burden on caregivers was assessed using a Caregiver Burden Questionnaire (CBQ). The overall aggregate burden and burden across 3 domains—socioeconomic, emotional, and psychological—was evaluated. Depressive symptomatology was evaluated using a Patient Health Questionnaire–9 (PHQ-9) standard questionnaire and graded from mild to severe. Results The mean age of the presenting children was 8.11±46.71 months; all of them were male. The mean age of the study participants was 33.6±8.36 years (53 female, 2 male). Thirty-nine (71%) individuals were identified to have moderate aggregate burden and 3 (5%) had severe aggregate burden. Twelve (22%) subjects were noted to have moderate depression, while 6 of them (11%) had either severe or very severe grades of depression. Conclusions Caregivers of patients with primary congenital glaucoma have significant emotional and psychological burden. Moderate to severe depression may be present in one-third of individuals giving primary care to children with congenital glaucoma.

Test-retest variability of retinal nerve fiber layer thickness and macular ganglion cell-inner plexiform layer thickness measurements using spectral-domain optical coherence tomography.

Purpose:To evaluate the test-retest variability of spectral-domain optical coherence tomography (OCT) in measurement of retinal nerve fiber layer (RNFL) thickness and macular ganglion cell-inner plexiform layer (GCIPL) thickness. Methods:A total of 65 eyes of healthy subjects were enrolled in this observational cross-sectional study. RNFL thickness and GCIPL thickness were measured using the repeat scan optic cube and macular cube protocol using Cirrus HD-OCT (software version 6.0). A single operator obtained 3 measurements during 1 session to determine test-retest variability. Intrasession repeatability was defined by intraclass correlation, limits of agreement, and coefficient of variation. Results:The mean age of patients was 37.89±15.11 years (range, 10 to 70 y). The mean RNFL thickness readings as measured during 3 sessions were 93.89±9.73, 93.63±10.00, and 93.55±9.64 &mgr;m and average GCIPL thickness measurements were 82.90±4.61, 82.98±4.24, and 83.06±4.36 &mgr;m, respectively. Coefficient of variation was 1.2 for average RNFL thickness and 0.82 for average GCIPL thickness. The intraclass correlation coefficient showed a good correlation between repeat measurements for both average RNFL and GCC thicknesses (0.994 and 0.990, respectively). The limits of agreement (95% confidence interval) for the 3 sessions ranged from −3.61 to 4.13 &mgr;m for the average RNFL thickness and −2.55 to 2.40 &mgr;m for GCIPL thickness measurements. Conclusions:In healthy eyes, Cirrus HD-OCT shows excellent intrasession repeatability for RNFL and GCIPL thickness measurements.

Evaluation of Major Depressive Disorder in Patients Receiving Chronic Treatment with Topical Timolol

Purpose: It was the aim of this study to evaluate the prevalence of major depressive disorder (MDD) in chronic glaucoma patients on a topical β-blocker (timolol). Design: An observational case control study was performed. Methods: The subjects recruited were divided into 3 groups. Group I included 98 patients with chronic glaucoma on topical β-blocker therapy, group II included 64 chronic glaucoma patients on prostaglandin analogues, and group III included 150 normal controls. All subjects were screened for MDD by the self-administered questionnaire Prime-MD Today (Primary Care Evaluation of Mental Disorders, New York, N.Y., USA). Results: The control group had a significantly higher age (p < 0.001) compared to the glaucoma patients on timolol or prostaglandin analogues; 9/98 patients (9.2%) on timolol, 1/64 patients (1.5%) on prostaglandins and 3/150 (2%) control subjects were screened positive for MDD. The odds ratios adjusted for age, sex and duration of glaucoma showed that patients on β-blocker therapy were 6.4 and 4.9 times more likely to have depression compared to those on prostaglandin analogues and control subjects, respectively. Conclusions: Glaucoma patients on topical timolol should be screened for depression and referred for appropriate psychiatric consultation and treatment if indicated.

Test retest variability of TonoPen AVIA

The study was conducted to evaluate the intra-session repeatability of Tonopen AVIA (TPA). 180 eyes of 180 patients (50 eyes with glaucoma, 130 eyes of controls) were recruited for this observational study. The mean age of patients enrolled in the study was 43.9 ± 16.7 yrs (84 males, 96 females). Mean IOP recorded with Tonopen AVIA was 19.5 ± 9.5 mmHg, 19.4 ± 9.6 mmHg and 19.3 ± 9.2 mmHg, respectively in the first, second and third instances (P = 0.656). The intraclass correlation coefficient (ICC) ranged from 0.996 (95% CI: 0.956 - 0.998) for glaucoma subjects to 0.958 (95% CI: 0.934 - 0.975) for controls. The coefficient of variation in the study population ranged from 3.47% (glaucoma patients) to 8.10% (healthy controls), being 6.07% overall. The coefficient of repeatability varied between 2.96 (glaucoma patients), 3.35 (healthy controls) to 3.24 (overall). Thus, the Tonopen Avia shows good intrasessional repeatability of IOP in both glaucomatous patients and healthy subjects.

Prevalence of plateau iris configuration in primary angle closure glaucoma using ultrasound biomicroscopy in the Indian population

Purpose: To report the prevalence of plateau iris in patients with primary angle closure glaucoma (PACG), in North India. Materials and Methods: The patients with PACG, attending the glaucoma services at a tertiary care center in North India were included in the study. All patients had undergone Nd-YAG laser peripheral iridotomy at least four weeks prior to inclusion in the study. Four weeks prior to inclusion in the study, none of the patients had used pilocarpine. Ultrasound Biomicroscopy (UBM) images were qualitatively evaluated and plateau iris configuration was defined in an eye if the following criteria were fulfilled in two or more quadrants: anteriorly directed ciliary process supporting the peripheral iris, steep rise of iris root from its point of insertion followed by a downward angulation from the corneoscleral wall, absent ciliary sulcus, and iridotrabecular contact in the same quadrant. Results: One hundred and one eyes were included in the study. There were 63 (62.4%) females and 38 (37.6%) males. The mean age of the patients was 57.8 ± 9.5 years (range: 42 to 78 years). The mean axial length in the study population was 22.2 ± 1.1 mm. The mean spherical equivalent refraction was 0.06 ± 1.12 D. The mean intraocular pressure was 18.5 ± 4.7 mmHg (range: 12 – 24 mmHg). Twenty-nine (28.7%) subjects were diagnosed with plateau iris on the basis of above-defined criteria. Of the 29 eyes, 18 (62.1%) subjects had plateau iris in two quadrants, nine (31.03%) in three quadrants, and two (6.8%) had this configuration in all the four quadrants. Conclusions: Approximately 30% of the eyes with PACG had plateau iris on UBM. Plateau iris was very often the cause for residual angle closure following laser peripheral iridotomy in Indian eyes with PACG.