Journal of Ophthalmology and Eye Disorders www.directivepublications.org Cirrus HD OCT in Pediatric Population Measures Retinal Nerve Fiber Layer Thickness and Optic Disc Parameters in Anisometropic Amblyopia Future Navendran B Institutional affiliations Postgraduate Institute of Ophthalmology, India Corresponding author

Navendran B, Eye Hospital & Postgraduate Institute of Ophthal- mology, India, E-mail: navendran_b2004@yahoo.co.in Received Date: November 27 2021 Accepted Date: November 29 2021 Published Date: December 25 2021 Abstract Background: Cirrus HD Oct. to examine the peripapillary retinal nerve fibre layer (RNFL) thickness associated with blind spot param- eters in visual disorder and fellow eyes in medical specialty patients with an isometropic vision defect. Method: This was a prospective, cross-sectional study that includ- ed cardinal subjects with newly diagnosed eye conditions and vision defects. All children had an ophthalmic examination, which included acuity and optical coherence imaging (Cirrus Oct Zeiss, ‘Optic Disc Cube 200200’ protocol). Each visual disorder and traditional fellow eyes were in deep trouble when measuring the Retinal nerve fibre layer and second cranial nerve head parameters (ONH). Results: The mean best corrected acuity (log MAR scale) of the conventional and visual disorder eyes was statistically significant. Among the four quadrant and twelve o’clock hour sector analyses, nasal and temporal sectors had significant differences between visual impairment and traditional eyes (P=0.027, P=0.045, respectively). The common cup-to-disc space quantitative relation and cup volume were lower in the visual impairment eyes than in the fellow eyes among the ONH parameters. None of the opposite ONH parameters were signifi- cantly different between the examined eyes. Conclusion:There was no difference in average RNFL thickness between visual impairment and traditional fellow eye. Several mor- phological measurements between the visual impairment and fellow eyes in patients with unilateral visual impairment were significantly different. Keywords visual impairment eye condition; thickness of the peripapillary retinal fibre layer; optic nerve; head parameters; Cirrus HD Month of the Gre- gorian calendar Introduction Amblyopia is defined as a decrease of sensory system that no causes is detected by the physical examination of the eye, caused by vision depri- vation or abnormal binocular interaction [1]. handicap is that the one of the foremost common clarification for visual loss in children mov- ing zero.2% to 1.1% of school going children. The causes of handicap in decreasing order of prevalence area unit strabismic, eye condition, mixed, ametropic, meridional and sensory deprivation handicap [1,2]. A distinction in refractive error between the two eyes (anisometropia) might be a typical clarification for handicap, being gift as a result of the only identifiable amblyogenic suppose thirty seventh of cases and gift concomitantly with abnormality in a very any pure gold of clinical populations [2]. The literature and experimental studies had delineate the pathophysiology structural changes in handicap at fully totally dif- ferent levels of the visual information science pathway. The anatomical changes square measure delineate at the plant part, lateral body structure and retinal levels [3]. There tinal fiber layer thickness (RNFL) thickness studies with optical coherence picturing (OCT) are wiped out varied ethnic population in paediatric and adult cohort with visual impairment [3-10]. varied studies have delineate changes altogether youngsters regardless of whether or not they were recently diagnosed, persistent or immune to occlusion and refractory medical aid. Changes in peripapillary and region are shown to be inconsistently associated with the visual impairment standing of the attention [11-17]. Studies victimization Gregorian calendar month imaging of the membrane have variable results, some studies have found associate accrued peripapillary RNFL or/and macular thickness in visu- al impairment eyes, whereas others have found no important variations between visual impairment and healthy eyes [17-24]. There has been scarceness of literature describing the changes in sec- ond cranial nerve parameters (ONH) and twelve sector RNFL changes in eye condition ambylopia. Hence, this study was done to judge the changes in thickness of RNFL and optic disk parameters in paediatric patients with recently diagnosed eye condition visual impairment. Materials and ways This study was conducted at the Department of medical specialty medicine at Aravind Eye Hospital. This study adhered to the Declara- tion of Helsingfors and was approved by the institutional review board. consent was taken from folks or guardians. Unilateral visual defect was outlined as a best corrected sight (BCVA) of a minimum of a two-line distinction between the amblyopic and fellow eye. All the patients aged five to seventeen yrs with new diagnosed eye condition visual defect (defined as one D or larger in spherical equivalent, or a 1.5 D or larger distinction in astigmatism between each the eyes within the absence of any measurable heterotropia at distance or near) with traditional show- ing disc, cup and neuroretinal rim on examination of the second cranial nerve head with + 90D motor-assisted stereoscopic slit - lamp indirect ophthalmoscopes were registered within the study. Patients with abnor- mal condition, ocular motility disorders, any pathologies of retinal fiber Review Article

Journal of Ophthalmology and Eye Disorders www.directivepublications.org RNFL thickness of the visual impairment eye (Correlation constant - zero.5124, P =0.0016) (Figure a & b). There was a correlation between spherical equivalent and RNFL thickness (P=0.0017) whereas correlational statistics between Axial length and RNFL thickness in ambyloic eyes. (P =0.0016) The (Table 4) shows relationship between the mean disc space, mean rim space, and mean vertical CD quantitative relation of the traditional eye and also the visual impairment eye to be statistically insignificant (P >0.05). The mean average cup-to-disc space quantitative relation and cup volume was lesser within the visual impairment eyes than within the fellow eyes (P=0.042, P=0.023 respectively).

Discussion I Jetal. within their meta-analysis of twenty eight clinical trials involving 408 patients discovered that pRNFL thickness within the visual disorder eyes was thicker than in the fellow eyes (P= zero.016) [24]. In our study, mean RNFLT was four.94 µm thicker within the temporal clock hour of visual disorder eye than the guy eye, that was statistically significant (P-value zero.045). Similarly, the mean RNFLT was four.49 µm thicker in nasal quadrant of the visual disorder than the guy eye, the distinction being statistically significant (P –value zero.027). In contrary to our study, studies done by Repka, et al. [8] Dickman, et al. [7] Firat, et al. [15] Kee SY, et al. [5] Bandhopadhya, et al. [12] Huynh, et al. [6] Quoc EB, et al. [9] and Wang, et al. [19] found no significant distinction all told the four quadrants between the visual disorder and fellow eyes. Demircan, et al. [25] found no significant distinction all told four quadrants and also the twelve sectors once on an individu- al basis compared between eye condition eye and traditional eye. In gift study the mean RNFL was four.49 µm thicker in nasal quad- rant of the visual disorder than the guy eye, the distinction be- ing statistically vital (P =0.027). In contrary to our study, stud- ies done by Repka, et al. Dickman, et al. Firat, et al. Kee SY, et al. Bandhopadhya, et al. Huynh, et al. Quoc EB, et al. and Wang et al found no vital distinction all told the four quadrants between the visual disorder and fellow eyes [5-9,12,14-18]. Ersan, et al. ac- cording within the hypermetropic eye condition cluster, temporal

RNFL thickness was diluent in visual disorder eyes (66.32 ± 16.84 μm) compared to their fellow eyes (71.23 ± 15.00 μm) (P=.03), whereas within the myopic eye condition cluster, superior RNFL thickness was considerably diluent within the visual disorder eyes (112.12 ± 18.54 μm) than their fellow eyes (123.12 ± 20.85 μm) (P = .05) [13]. Demircan, et al. found no vital distinction all told four quadrants and also the every six sectors focused on the optic disk ( temporal, temporal superior, tem- poral inferior, nasal, nasal inferior, nasal superior) by Spectralis October between eye condition visual disorder and traditional fellow eye [25]. We didn’t notice any studies describing twelve clock hour sector anal- yses between traditional and eye condition visual disorder eyes. Few studies have taken in account of axial length in visual disorder eyes [3,6,25]. we tend to found a direct correlation between the spherical equivalent and peripapillary RNFL thickness in visual disorder eye, kind of like study by Ersan, et al. WHO found that RNFL measurements showed a major direct correlation with spherical equivalent within the layer or disc, case history of eye disease or any intraocular surgery or any reasonably optical device medical aid, mentally challenged young- sters, any general diseases touching eye were excluded from study. All subjects received a full ophthalmic examination together with cycloplegic refraction, assessment of ocular motility, slit-lamp biomi- croscopic analysis, expanded structure examination and axial length by IOL master© (Carl Zeiss Meditec, Dublin, CA) (ver. 5.2.1). Pupils were expanded with tropicamide I Chronicles and cyclopen- tolate I Chronicles drops, counting on age of the topic. RNFL was mea- sured through expanded pupils employing a third generation optical co- herence tomographer (Cirrus OCT©, model HD-OCT 4000, Carl Zeiss Meditec, Dublin, CA) (ver.3.0.0.64). Peripapillary measurements were measured victimization the quick scan protocol (fast RNFL thickness scan). 3 200×200-cube point scans were done in turn, with a complete acquisition time of 1.5 s. the common of the three scans was analyzed. All scans were performed by identical investigator. an interior fixation target was employed in all scans, and also the location of every scan on the tissue layer was monitored on the intrinsic infrared-sensitive video camera. The mean RNFL thicknesses at 256 cubes of the RNFL thickness were recorded and also the average RNFL thicknesses all told quadrants were analyzed. RNFL thickness (all four quadrants: superior, nasal, inferior and temporal, average, and clock hours), RNFL symmetry, rim area, disc area, average C/D quantitative relation, vertical C/D quantitative rela- tion and cup volume were recorded. For the clock hour RNFL thick- nesses, twelve 30° sectors were outlined in dextrorotatory order for the proper and left eyes; in this respect, clock hour one within the right eye corresponded to clock hour eleven within the left eye, clock hour two within the right eye corresponded to clock hour ten within the left eye, 3–9, 4–8, 5–7 severally, etc. Statistical Analysis The BCVA was remodeled to exponent of the minimum angle of resolu- tion (log MAR) units for the applied mathematics analysis. Mean (SD) or frequency (percentage) was wont to describe outline information. Paired t-test / Wilcoxon Signed Rank take a look at was wont to take a look at mean distinction of retinal fiber layer thickness and ocular parameters between visual impairment eye and traditional eye. P-value but 0.05 were thought-about as statistically important. All the applied mathematics analysis was performed victimization STATA eleven.1© (Texas, U.S.A). Results The mean age of patients was nine.83 ±3 (5-17 years). there have been nineteen myopic and sixteen farsighted anisometropes. The clini- cal characteristics of traditional and visual impairment eyes ar delineat- ed in (Table1). the common RNFL thickness within the traditional eye was ninety six.34 ± 9.3 µm (range seventy six – 122 µm) whereas that of the visual impairment eye was 97.94 ± eleven µm (range 77-125 µm) that wasn’t important (P= zero.294). There was a correlation between spherical equivalent and RNFL thickness in visual impairment eye (Correlation constant zero.5123, P =0.0017). There was a correlational statistics between axial length and Review Article

Journal of Ophthalmology and Eye Disorders www.directivepublications.org Korean J Ophthalmol 20(3): 177-181. 6. Huynh SC, Samarawickrama C, Wang XY, Rochtchina E, Wong TY, et al (2009) Macular and nerve fiber layer thickness in am- blyopia: the Sydney Childhood Eye Study. Ophthalmology 116(9):1604–1609. 7. Dickmann A, Petroni S, Salerni A, Roberto D, Emilio B (2009) Unilateral amblyopia: an optical coherence tomography study. JAAPOS 13(2): 148-150. 8. Repka MX, Kraker RT, Tamkins SM, Donny WS, Nicholas AS, et al (2009) Retinal nerve fiber layer thickness in amblyopic eyes. Am J Ophthalmol 148(1): 143-147. 9. Quoc EB, Delepine B, Tran TH (2009) Thickness of retinal fiber layer and macular volume in children and adults with strabismic and anisometropic amblyopia. J Fr Ophtalmol 32(7): 488-495. 10. Miki A, Shirakashi M, Yaoeda K, Kabasawa Yu, Satoshi U, et al (2010) Retinal nerve fiber layer thickness in recovered and per- sistent amblyopia. Clin Ophthalmol 20(4): 1061-1064. 11. Al-Haddad CE, Mollayess EL, Cherfan CG,Dalida J, Bashshur Z(2011) Retinal nerve fibre layer and macular thickness in ambly- opia as measured by spectral-domain optical coherence tomogra- phy. Br J Ophthalmol 15(1): 11. 12. Bandyopadhyay SK, Chatterjee A, Banerjee R (2012) Peripapil- lary nerve fibre layer thickness and macular thickness in children with anisometropic amblyopia attending a referral centre in East- ern India. J Indian Med Assoc 110(8): 542-545. 13. Ersan I, Zengin N, Bozkurt B, Ozkagnici A (2013) Evaluation of retinal nerve fiber layer thickness in patients with anisometropic and strabismic amblyopia using optical coherence tomography. J Pediatr Ophthalmol Strabismus 50(2): 113-11. 14. Andalib D, Javadzadeh A, Nabai R, Amizadeh Y (2013) Macu- lar and retinal nerve fiber layer thickness in unilateral anisome- tropic or strabismic amblyopia. J Pediatr Ophthalmol Strabismu 50(4):218-221. 15. Firat PG, Ozsoy E, Demirel S, Cumurcu T, Abuzer G (2013) Eval- uation of peripapillary retinal nerve fiber layer, macula and gan- glion cell thickness in amblyopia using spectral optical coherence tomography. Int J Ophthalmol 6(1): 90-94. 16. Wu SQ, Zhu LW, Xu QB,Xu JL, Zhang Y (2011) Macular and peripapillary retinal nerve fiber layer thickness in children with hyperopic anisometropic amblyopia. Int J Ophthalmol 6(1): 85-89. 17. Alotaibi AG, Enazi BA (2011) Unilateral amblyopia: Optical co- herence tomography findings. Saudi Journal of Ophthalmology 25(4): 405-409. 18. Dickmann A, Petroni S, Perrotta V, Parrilla R, Aliberti S (2012) Measurement of retinal nerve fiber layer thickness, macular thick- ness, and foveal volume in amblyopic eyes using spectral-domain optical coherence tomography. JAAPOS 16(1): 86-88. eye condition cluster (both myopic and hypermetropic) [13]. While Yen, et al. showed that there was no vital correlation between RNFL thickness and spherical equivalence (P = zero.956) among all visual disorder eyes [3]. Repka, et al. conjointly had similar conclusion of no association between RNFL thickness and presbyopic refractive error within the visual disorder eye (P=0.81) or sound eye (P = zero.28) [8]. We had correlation between the axial length and RNFL of the vi- sion defect eyes. In contrary to our study, Yen et al. showed that there was no very important correlation between RNFL and axi- al length (P = zero.655) among all vision defect eyes [3]. Araki S, et al. showed that the variations among the peripapillary RNFL thick- ness were significantly correlate with the excellence in axial length (P However our study has few limitations. If a bigger study popula- tion had been taken, it might be a lot of useful to assess the changes mentioned higher than. The results will then be reckon to the overall population. we have a tendency to additionally didn’t have a bear- ing cluster of subjects. The variables of the conventional fellow eye will then be compared with the attention of the management subjects. the info obtained from our study applies solely to Cirrus HD-OCT. It can’t be compared to it obtained by alternative spectral domain Oc- tober machine. we have a tendency to didn’t embody a correction think about respect to age, axial length, refraction and magnification in RNFL, before subjecting it to additional applied math analysis. Conclusion We found no distinction between RNFL thickness in visual defect and traditional fellow eye but nasal quadrant, temporal clock hour sec- tor, average CD quantitative relation, cup volume showed vital varia- tions. therefore a number of the morphological measurements between the visual defect and fellow eyes in patients with unilateral vision de- fect were considerably completely different. additional studies, together with histopathlogical and individual retinal layer analysis with a bigger range of patients, ar needed to establish the variations between visual defect and traditional eyes. References 1. Pediatric Eye Disease Investigator Group (2002) The clinical profile of moderate amblyopia in children younger than 7 years. Arch Ophthalmol 120(3): 281- 287. 2. Menon V, Chaudhuri Z, Saxena R, Gill K, Sachdev MM (2005) Profile of amblyopia in a hospital referral practice. Indian J Oph- thalmol 53(4): 227-234. 3. 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