Diagnostic Protocol for Accommodative and Vergence Anomalies - A Review.

PURPOSE: To review the diagnostic protocols of non-strabismic binocular vision anomalies. METHODS: We carried out a literature search on published articles of non-strabismic accommodative and vergence anomalies in different international optometry and ophthalmology journals found in the Pubmed, ResearchGate, Google Scholar, and MEDLINE databases. RESULTS: The diagnostic criteria and normative data from the nine articles selected show discrepancies and variability in methodologies and techniques in the overall assessment of Non-Strabismic Binocular Vision Anomalies (NSBVA). Near point of convergence measurement is the most common assessment, whereas the vergence facility is the least commonly used assessment in terms of evaluating convergence insufficiency. Near point of convergence > 10 cm alone is the most sensitive sign to detect convergence insufficiency in a community set-up but high positive relative accommodation (>3.50D) is the most sensitive sign to diagnose accommodative excess. On the other hand, monocular accommodative facility < 7 CPM has the highest sensitivity to confirm the diagnosis of accommodative infacility. This review also indicates that the more clinical signs that are included in a set of diagnostic criteria, the lower the prevalence rate for that diagnosis. CONCLUSIONS: There is no standardized and diagnostically validated protocol for the assessment of NSBVAs. Variable cutoff values obtained using different methods and the selection of diagnostic criteria by various researchers have led to discrepancies that highlight the need for diagnostic validity of available protocols (combination of tests) for each anomaly. Clinical signs such as positive relative accommodation (PRA) for accommodative excess, near point of convergence (NPC) for convergence insufficiency and monocular accommodative facility (MAF) for accommodative infacility were found to be useful diagnostic signs of these anomalies. Studies should be carried out for accommodative and vergence dysfunctions using proper designs and methods to validate diagnostic criteria for all age groups. Standardization of assessment protocol and cutoff criteria will also aid in calculating prevalence for non-strabismic binocular vision anomalies.

Genetic diversity and phylogeny analysis of Antheraea assamensis Helfer (Lepidoptera: Saturniidae) based on mitochondrial DNA sequences.

Antheraea assamensis Helfer, popularly known as Muga silkworm, the golden silk producer of northeast India is economically important and unique among the Saturniid silkworms. In this study, the genetic diversity and phylogeny of semidomesticated and wild morphs of Muga silkwormcollected from different geographical locations of northeast India were investigated based on the sequences of five mitochondrial loci, i.e. 12S rRNA, 16S rRNA, CoxI, Cytb and CR. All the five mitochondrial loci showed a strong bias towards higher 'A' and 'T' contents. Transitional substitutions were found to be more than the transversional substitutions. The rate of nucleotide substitution and average genetic divergence were found to be highest in CR sequences and lowest in 12S rRNA gene sequences among the morphs of Muga silkworm. The morphs collected from same geographical area had identical 12S rRNA, 16S rRNA, CoxI and Cytb gene sequences. Moreover, the 12S rRNA and 16S rRNA gene sequences of somesemi-domesticated and wild morphs collected from different geographical locations were also found to be similar. In the phylogenetic trees generated based on themitochondrial loci, mixing of semi-domesticated and wild morphs was observed as they shared the same group. The information generated in this study will help in formulating strategies to conserve the natural biodiversity present among these unique silkworms in northeast India. In addition, this will be useful in identifying diverse morphs of Muga silkworm, which will help in effective breeding programmes to improve its productivity.

Analysis of genetic diversity and phylogeny of Philosamia ricini (Lepidoptera: Saturniidae) by using RAPD and internal transcribed spacer DNA1.

The Indian Eri silkworm, Philosamia ricini Hutt, a commercial silk producing insect, is believed to have originated in the Brahmaputra valley of Assam. In this study, the genetic diversity and phylogenetic relationships of six morphs of Eri silkworm viz. white plain, white zebra, white spotted, blue plain, blue zebra and blue spotted collected from different geographical locations of North-East India were investigated by using random amplified polymorphic DNA (RAPD) and the first internal transcribed spacer region (ITS1). This study revealed a low genetic diversity among the morphs of Eri silkworm. Twenty-eight random primers generated 199 bands. Out of these, 112 were polymorphic (56.28%) with an average of 7.1 bands per primer. The genetic similarity matrix ranged from 0.56 to 0.99. The morphs collected from same geographical area shared the same cluster in the dendrogram. The genetic diversity in case of ITS1 sequences (2.19%) was found to be less as compared to RAPD. The ITS1 sequences of the morphs collected from same geographical area were found to be identical. The information generated in this study will help in conservation and effective breeding program to improve its productivity.

Health-Related Quality of Life (HRQoL) in Young Adults with Strabismus in India.

INTRODUCTION: Strabismus has negative psycho-social and functional effects in adults. The impact can be minimised with surgery. However, in a low-income setting, it is important to evaluate the level of impact and prioritise the target population for intervention. The Adult Strabismus (AS-20) questionnaire is a reliable tool for assessment of Health-Related Quality of Life (HRQoL) in strabismic adults. AIM: To assess the HRQoL in young adults with manifest strabismus through psychosocial and functional scores according to gender and direction of deviation using the AS-20 questionnaire. MATERIALS AND METHODS: In this cross-sectional cohort study, 132 young adults who manifest horizontal strabismus were recruited and the AS-20 questionnaire was administered. Patient's demographic profile and type of strabismus were noted and compared with the overall mean scores of psycho-social and functional subscales. Data was analyzed using SPSS 21 and p-value less than 0.05 was considered statistically significant. RESULTS: The participants comprised of 70 (53.03%) males and 62 (46.97%) females with a mean age of 24.5±3.57 years (range 18 to 38 years). The overall mean AS-20 score of young adults with strabismus was 61.62±12.61. The overall mean score for male and female were 65.54±13.53 and 57.68±13.46, respectively. Similarly, the mean scores for esotropes was 57.03±11.66 and 66.19±15.30 for exotropes. The overall mean scores were statistically significantly reduced (decreased QoL) in females as compared to males (CI 95%; p=0.002) and in esotropes as compared to exotropes (CI 95%; p=0.001). However, there was no significant difference between the psychosocial and functional score for all types of strabismus and genders (for all, p>0.05). CONCLUSION: The Quality of Life (QoL) is affected through psychosocial and functional factors in adults with strabismus. Females and adults with esotropia faced greater difficulties in the QoL. We recommend clinicians to consider the impact on QoL while managing adult with strabismus.