Two cases of Duane retraction syndrome with abnormal orbital structures.

Duane retraction syndrome (DRS) is a rare congenital nonprogressive restrictive strabismus. The absence/hypoplasia of the abducens nerve and the aberrant innervation of the lateral rectus muscle by the oculomotor nerve have been hypothesized as causes of DRS, although the phenomenon of globe retraction can also occur in the setting of mechanical factors, such as congenital abnormal orbital structures or orbital trauma. We present the cases of 2 DRS patients with absent abducens nerve and abnormal muscular bands connecting the superior rectus and inferior rectus muscles on the temporal side of the optic nerve.

Magnetic Resonance Imaging Findings in Patients With Duane Retraction Syndrome.

BACKGROUND: Duane retraction syndrome (DRS) is known to relate to the absence of the abducens nucleus, with abnormal innervation of the lateral rectus (LR) muscle by branchesof the oculomotor nerve (CN III). The purposes of this study were to investigate the morphological characteristics of the oculomotor nerve (CN III), the abducens nerve (CN VI), and the extraocular muscles in patients with clinically diagnosed Duane retraction syndrome (DRS) using MRI. In addition, we assessed the association between ocular motility, horizontal rectus muscle volumes, and CN III/VI in patients with Duane retraction syndrome (DRS). METHODS: The study comprised 20 orthotropic control subjects (40 eyes) and 42 patients with Duane syndrome (48 eyes), including 20 patients with DRS Type I (24 eyes), 5 patients with DRS Type II (6 eyes), and 17 patients with DRS Type III (18 eyes). Three-dimensional (3D) T1/2 images of the brainstem and orbit were obtained to visualize the cranial nerves, especially the abducens (VI) and oculomotor (III) nerves, as well as extraocular muscles. RESULTS: Based on the clinical classification, among 42 patients, MRI showed that the abducens nerves (CN VI) on the affected side were absent in 24 of 24 eyes (100%; 20 patients) with Type I DRS and in 16 of 18 eyes (88%; 16 patients) with Type III DRS. However, CN VI was observed in 6 of 6 eyes (100%; 5 patients) with Type II DRS and in 2 of 18 eyes (11%) with Type III DRS. CN III was observed in all patients. The oculomotor nerves on the affected side were thicker than those on the nonaffected contralateral side in DRS Type I ( P < 0.05) and Type III ( P < 0.05), but not in DRS Type II. Smaller LR and larger MR volumes were shown in the affected eye than that in the nonaffected eye in DRS Types I and III. Based on the presence or absence of CN VI, there was a tendency for thicker oculomotor nerves in the affected eye than in the nonaffected eye in the absence groups ( P < 0.05). However, no significant difference was found in the present group. In the CN VI absence groups, similar results were found in the affected eyes than in the nonaffected eyes as in DRS Types I and III. In addition, the presence of CN VI was correlated with better abduction ( P = 0.008). The LR and MR volumes have positive correlations with the oculomotor nerve diameter in the affected eye. However, there was no correlation between the range of adduction/abduction and the LR/MR ratio in patients with or without an abducens nerve. CONCLUSIONS: Different types of DRS have different characteristic appearances of CN VI and CN III on MRI. Horizontal rectus muscles have morphological changes to adapt to dysinnervation of CN VI and aberrant innervation of CN III. Thus, these neuroimaging findings may provide a new diagnostic criterion for the classification of DRS, improving the comprehension of the physiopathogenics of this disease.

Síndrome de Duane: a propósito de un caso / Duane syndrome: a case report

El síndrome de Duane es una enfermedad poco frecuente en la cual se observa retracción del globo ocular y limitación de los movimientos horizontales. Presentamos el caso de un paciente de 11 años que acudió a Urgencias debido a una desviación ocular supuestamente de reciente instauración. En la exploración se objetiva un déficit en la abducción y la aducción, así como cierre de la fisura palpebral en la aducción forzada. Se diagnostica de síndrome de Duane tipo III y se decide manejo conservador con observación y seguimiento (AU)

Duane syndrome is a rare condition, whose clinical presentation involves retraction of the eyeball upon attempted abduction, and limitation of horizontal movements. We present the case of an 11-year-old patient who presented to the Emergency Department with a recent-onset ocular deviation. Examination revealed a deficit in abduction and adduction, as well as closure of the palpebral fissure in forced adduction. The patient was diagnosed with Duane syndrome type III, and conservative management with observation and follow up was decided. (AU)

Palpebral Fissure Changes in the Contralateral Eye in Duane Retraction Syndrome.

Duane retraction syndrome (DRS) is a congenital cranial dysinnervation disorder that is characterized by paradoxical lateral rectus muscle innervation of the affected eye by axons meant to innervate the ipsilateral medial rectus muscle, with resultant varying degrees of co-contraction. It is characterized by severe abduction deficiency, variable limitation of adduction, globe retraction with narrowing of the palpebral fissure, and oblique elevation or depression on adduction. A total of 16 patients with unilateral DRS were identified. The mean age was 13 ± 8 years (range: 6 to 28 years). There were 5 males and 11 females. The cohort included 8 patients with DRS type I, 3 patients with DRS type II, 4 patients with DRS type III, and 1 patient with synergistic divergence (DRS type IV). The mean width of the palpebral fissure in primary gaze was 9.95 ± 0.25 mm, increased in abduction to 11.11 ± 1.16 mm, and changed on adduction to 10.03 ± 1.19 mm. The mean reduction in the size of the palpebral fissure on adduction was 11.7 ± 10.2% (range: 0 to 30%). The difference in the palpebral fissure width between adduction and abduction was statistically significant (P = .0018). Of the 16 patients, 8 (50%) showed narrowing of the palpebral fissure of the contralateral eye on adduction compared to abduction of more than 10%. In this case series of unilateral Duane retraction syndrome, there was a common association between widening of the palpebral fissure of the unaffected eye and adduction of the eyes with DRS in DRS types II, III, and IV and DRS type I with upshoot or downshoot. [J Pediatr Ophthalmol Strabismus. 2023;60(3):e22-e25.].

Orbital leiomyoma presenting as inverse globe retraction syndrome: a unique presentation of a rare disease.

Inverse globe retraction syndrome is a rare ocular motility disorder characterized by limited abduction, with globe retraction and up- or downshoots on attempted abduction, differentiating it from globe retraction due to Duane retraction syndrome, seen on attempted adduction. It can be congenital or acquired. We report the case of a 3-year-old girl who presented with classical features of inverse globe retraction syndrome secondary to an underlying orbital tumor involving the medial rectus muscle. Incisional biopsy confirmed the diagnosis of a leiomyoma. At 10 months' follow-up, vision, ocular alignment, and ocular motility had improved.

Concomitant Unilateral Duane Retraction Syndrome and Contralateral Brown's Syndrome.

A 10-year-old boy was introduced with a chief complaint of ocular misalignment from birth. Ocular examination indicated right Brown and left Duane retraction syndrome in a non-familial pattern. We suspect that a teratogenic damage or genetic mutation may be responsible for this combination.

Clinical and genetic characteristics of Chinese patients with congenital cranial dysinnervation disorders.

BACKGROUND: Congenital cranial dysinnervation disorders (CCDDs) are a group of diseases with high clinical and genetic heterogeneity. Clinical examinations combined with Magnetic resonance imaging (MRI) and whole exome sequencing (WES) were performed to reveal the phenotypic and genotypic characteristics in a cohort of Chinese CCDDs patients. RESULTS: A total of 122 CCDDs patients from 96 families were enrolled. All patients showed restrictive eye movements, and 46 patients from 46 families (47.9%, 46/96) were accompanied by multiple congenital malformations. Multi-positional high-resolution MRI was performed in 94 patients from 88 families, of which, all patients had hypoplasia of the cranial nerves except HGPPS patients and 15 patients from 15 families (17.0%,15/88) were accompanied by other craniocerebral malformations. WES was performed in 122 CCDDs patients. Ten pathogenic variants were detected in KIF21A, TUBB3, and CHN1 genes in 43 families. Three variants were unreported, including KIF21A (c.1064T > C, p.F355S), TUBB3 (c.232T > A, p.S78T) and CHN1 (c.650A > G, p.H217R). Of the 43 probands harboring pathogenic variants, 42 were diagnosed with Congenital Fibrosis of Extraocular Muscles (CFEOM) and one was Duane Retraction Syndrome (DRS). No definite pathogenic variants in known candidate genes of CCDDs were found in sporadic DRS, Möbius Syndrome (MBS) and Horizontal Gaze Palsy with Progressive Scoliosis (HGPPS) patients. The CFEOM patients harboring R380C, E410K and R262H variants in TUBB3 gene and F355S variant in KIF21A gene exhibited syndromic phenotypes. CONCLUSIONS: This study broadened the phenotypic and genotypic spectrums of CCDDs, and it was the largest clinical and genetic investigation for CCDDs patients from China. KIF21A and TUBB3 were the common pathogenic genes in Chinese CFEOM. MRI coupled with WES can provide a supportive diagnosis in patients with clinically suspected CCDDs.

Refractive error in unilateral Duane syndrome.

PURPOSE: To investigate whether chronic co-contraction of the medial and lateral rectus muscles leads to higher against-the-rule astigmatism in affected versus fellow eyes in Duane syndrome. METHODS: A database of 4,103 patients of Dr. Arthur Jampolsky was queried for diagnosis of Duane syndrome. Inclusion criteria were unilateral Duane syndrome and complete data set. Refractive error was compared between Duane and fellow eyes. RESULTS: A total of 84 patients with unilateral Duane syndrome were identified. The spherical equivalent of Duane eyes and fellow eyes was similar (0.4 vs. 0.2 [P = 0.14]). Mean cylinder power was higher in Duane eyes compared to fellow eyes (0.7 vs 0.4 [P = 0.0003]). There was modest evidence of more against-the-rule astigmatism in Duane eyes compared to fellow eyes (P = 0.04) but no difference for with-the-rule astigmatism (P = 0.83). Duane compared to fellow eyes were, however, significantly more likely to have oblique astigmatism (P = 0.004) or any astigmatism at all (P = 0.0005). CONCLUSIONS: Duane eyes compared to fellow eyes had higher astigmatism that was more likely to be oblique. Our study lends support to the hypothesis that extraocular muscles may influence refractive error.

Clinical characteristics and surgical approach in Duane retraction syndrome: a study of 691 patients.

PURPOSE: To evaluate the clinical findings of different types of Duane retraction syndrome (DRS). STUDY DESIGN: Retrospective. METHODS: This study was performed on 691 patients with DRS who underwent surgery. Clinical examinations included laterality, abnormal head posture (AHP), corrected distance visual acuity (CDVA), refractive error, amblyopia, deviation, overshoots, and type of surgery. RESULTS: The mean age of patients with DRS was 16.7 ± 12.5 (range 1.0-73) years. The patients included 396 (57.3%) women and 295 (42.7%) men (P < 0.001). DRS type I, was observed in 429 (62.1%), II in 168 (24.3%), III in 88 (12.7%) and IV in 6 (0.9%) patients. Unilateral DRS was observed OS in 628 (90.9%) [471 (%78.9) and OD in 157 (21.1%) eyes (P < 0.001)]. O ther clinical findings were AHP (n = 522, 78.1%), overshoot (n = 236, 34.2%) and amblyopia (n = 118, 17.1%). The prevalence of overshoot in types I, II, and III was 17.5% (75/429), 60.7% (102/168) and 64.8% (57/88), respectively (P < 0.001). The prevalence of amblyopia was significantly lower in patients with AHP (80/522, 15.3%) compared to patients with normal head posture (38/169, 22.5%) (P = 0.023). The mean angle of deviation in the primary position (PP) at distance was 21.7 ± 11.5 △ for esotropic group and 17.8 ± 12.4 △ for exotropic group. Sixty-two (9.0%) patients required second surgery for resolving residual misalignment (1.1 surgeries for each patient). CONCLUSIONS: About two-thirds of DRS patients had AHP, one-third had overshoots, and one-sixth had amblyopia. The results show that different types of DRS are associated with different epidemiological and clinical characteristics.

[Improvement of surgical treatment of Duane syndrome in children]. / Sovershenstvovanie khirurgicheskogo lecheniya sindroma Dueina u detei.

PURPOSE: To analyze the use of bifurcation of the lateral rectus muscle (LRM) in the surgical treatment of Duane syndrome (DS) in children. MATERIAL AND METHODS: The analysis of surgical treatment involved 12 children with paralytic strabismus at the age of 8 to 17. The following research methods were conducted for all patients: the study of eye motility in different directions of gaze, the study of eyes position and the degree of deviation in different positions of gaze, the Bielschowsky test, the Park's three-step test, determination of the nature of torticollis, the forcing test - intraoperative forceps test, multislice computed tomography (MSCT) of the head and orbit, ultrasonography of the oculomotor muscles. All study children underwent bifurcation (Y-cleavage procedure) of LRM with recession in exo-DS in 17% of cases, without recession in eso-DS - 83% of cases, respectively. RESULTS: In all operated patients with Duane syndrome, the direction of LRM was compensated (downshoot and upshoot were eliminated). In a direct gaze, the correct position was achieved in 10 (83%) cases, in 2 (17%) the residual angle of up to 10 PD remained, and torticollis was eliminated in 9 (75%) patients. CONCLUSION: The method of LRM bifurcation - the procedure of dividing the muscle into two portions and changing its primary localization, accompanied by abnormalities (presence of deviation, retraction, anomalous vertical movements, limited ocular motility, etc.), - helps compensate for them, and provides cosmetic as well as functional improvement.

Expanding the Phenotype of the FAM149B1-Related Ciliopathy and Identification of Three Neurogenetic Disorders in a Single Family.

Biallelic truncating FAM149B1 variants result in cilia dysfunction and have been reported in four infants with Joubert syndrome and orofaciodigital syndrome type VI, respectively. We report here on three adult siblings, 18 to 40 years of age, homozygous for the known FAM149B1 c.354_357delinsCACTC (p.Gln118Hisfs*20) variant. Detailed clinical examinations were performed including ocular and gait analyses, skeletal- and neuroimaging. All three patients presented with neurological and oculomotor symptoms since birth and mild skeletal dysplasia in infancy resulting in characteristic gait abnormalities. We document mild skeletal dysplasia, abnormal gait with increased hip rotation and increased external foot rotation, ataxia, variable polydactyly, ocular Duane syndrome, progressive ophthalmoplegia, nystagmus, situs inversus of the retinal vessels, olfactory bulb aplasia, and corpus callosal dysgenesis as novel features in FAM149B1-ciliopathy. We show that intellectual disability is mild to moderate and retinal, renal and liver function is normal in these affected adults. Our study thus expands the FAM149B1-related Joubert syndrome to a mainly neurological and skeletal ciliopathy phenotype with predominant oculomotor dysfunction but otherwise stable outcome in adults. Diagnosis of FAM149B1-related disorder was impeded by segregation of multiple neurogenetic disorders in the same family, highlighting the importance of extended clinical and genetic studies in families with complex phenotypes.

A 7-year old female with arthrogryposis multiplex congenita, Duane retraction syndrome, and Marcus Gunn phenomenon due to a ZC4H2 gene mutation: a clinical presentation of the Wieacker-Wolff syndrome.

Background: Duane retraction syndrome and arthrogryposis multiplex congenita have an incidence of approximately 1:1500-1:3000 live births. However, the association of these two entities with a Marcus-Gunn might be a rare and, until now, under-recognized clinical presentation of the Wieacker-Wolff Syndrome.Patient and methods: We report a 7-year-old female with dysmorphic features, global developmental delay, arthrogryposis multiplex congenita (AMC), Duane retraction syndrome (DRS), and unilateral Marcus Gunn jaw winking.Results: Whole Exome Sequencing showed a de novo premature stop codon in ZC4H2. Extensive genetic and metabolic work was negative otherwise and Brain MRI showed delayed non-specific myelination abnormalities. She continues to have significant delays but does not have regression, seizures or other neurological complications. She has required a multidisciplinary approach for the management of her multiple contractures.Conclusion: This case confirms ZC4H2 as a cause of syndromic DRS and extends the ZC4H2 phenotype to include Marcus Gunn jaw winking.

Pseudo-Duane retraction syndrome after orbital myositis.

Orbital myositis is a rare, commonly idiopathic, inflammatory condition that affects one or more extraocular muscles. We present a case of unilateral orbital myositis affecting the lateral rectus muscle presenting with gaze-evoked amaurosis, pain, and diplopia, with restrictive limitation of adduction. With improvement in adduction after initiating treatment, we noted narrowing of the palpebral fissure on attempted adduction, mimicking Duane retraction syndrome (DRS). Reported cases of "pseudo-DRS" are associated with multiple etiologies and are characterized by retraction on attempted abduction rather than adduction, as occurs in true DRS. In this case, pseudo-DRS occurred in the setting of idiopathic orbital inflammatory syndrome (orbital myositis) with a motility pattern more consistent with true DRS.

Variant types of Duane retraction syndrome: synergistic divergences and convergences.

PURPOSE: To present the clinical features of 4 patients with Duane retraction syndrome characterized by synergistic divergence or convergence, abnormal vertical movements, and accessory fibrotic bands. METHODS: The medical records of 4 patients were reviewed retrospectively for the following clinical manifestations: visual acuity, refraction, ocular alignments, ocular motility, head position, magnetic resonance imaging, surgical techniques, and outcomes. RESULTS: All 4 cases were diagnosed as variants of Duane retraction syndrome. Two cases (cases 1 and 2) had synergistic divergence with unilateral adduction deficit, and 2 (cases 3 and 4) had synergistic convergence with bilateral abduction deficit. Case 2 manifested abnormal vertical movements of the right eye, which goes down with adduction of the left eye and goes up oppositely with abduction of left eye. Accessory fibrotic bands were detected beside the medial rectus muscle of both eyes in case 3. Synergistic convergence in case 4 occurred only after the first strabismus surgery. Weakening of the misinnervated horizontal rectus muscle improved ocular alignment and head position in cases 1, 3, and 4. CONCLUSIONS: Synergistic divergence and convergence are extremely rare and may present with a great diversity of clinical features. A good outcome is very difficult to achieve; however, weakening of the misinnervated horizontal rectus muscle was therapeutic in these patients.

Eficacia y complicaciones de las transposiciones musculares en el síndrome de Duane con esotropía / Efficacy and complications of transposition surgery in Duane esotropia síndrome

OBJETIVO: Estudiar la eficacia a largo plazo y las complicaciones de varios tipos de transposición en el tratamiento del síndrome de Duane: la transposición muscular de rectos verticales total o parcial, la transposición sin desinserción muscular y la transposición del recto superior. MATERIAL Y MÉTODOS: Estudio retrospectivo de los pacientes diagnosticados de síndrome de Duane con esotropía operados con cualquier tipo de transposición muscular asociada o no al debilitamiento del recto medio con seguimiento mayor de 12 meses. Se consideró un buen resultado una desviación ≤ 10 dioptrías prismáticas (dp) en posición primaria de la mirada, tortícolis < 10° con mejoría de la abducción y sin diplopía. RESULTADOS: Un total de 7 casos fueron incluidos (6 mujeres, 6 unilaterales), con una edad media de 37,71 años. La esotropía inicial en posición primaria de la mirada de 28 ± 11,68dp disminuyó a 6 ± 4,62dp al final del seguimiento (p = 0,009). El tortícolis mejoró en 6, y la abducción mejoró un grado en todos (media: -3,14 a -2,14). En 4 casos apareció una desviación vertical ≤ 8dp. Ningún paciente tuvo diplopía final. El porcentaje de reintervenciones fue del 71,42%; solo un 28,57% obtuvo un buen resultado con una cirugía y ascendió a un 71,42% al final del seguimiento con cirugías adicionales. El tiempo de evolución medio fue de 52 ± 31,65 meses. CONCLUSIONES: Las transposiciones en el síndrome de Duane con signos clínicos moderados o severos han sido solo eficaces en una pequeña proporción de los casos. La mayoría requirió una segunda cirugía para corregir las complicaciones o las hipocorrecciones

OBJECTIVE: To study the long-term efficacy and the complications of several transposition techniques for the treatment of Duane syndrome. These included, full vertical rectus transposition, partial vertical rectus transposition, transposition without muscle disinsertion, and superior rectus transposition. MATERIAL AND METHODS: A retrospective study of the patients diagnosed with Duane syndrome, and who underwent any of the different transposition techniques associated or not to the medial rectus recession with a follow-up longer than 12 months. A good result was considered a final deviation ≤ 10 prism dioptres (pd) in primary position, anomalous head posture < 10°, and an improvement of the abduction without diplopia. RESULTS: Seven cases were included (6 women, 6 unilateral), and a mean age of 37.71 years. Pre-operative central gaze esotropia of 28 ± 11.68 pd decreased to 6 ± 4.62 pd at the final visit (P = .009). The anomalous head posture decreased in 6 patients, and the abduction improved one degree from -3.14 to -2.14 (mean). An induced vertical deviation ≤ 8pd was observed in 4 cases. None experienced diplopia at the final visit. The percentage of reoperations was 71.42%. Only 28.57% had a favourable outcome with a single surgery, which increased to 71.42% with further surgeries at the final follow-up. Mean evolution time was 52 ± 31.65 months. CONCLUSIONS: Vertical rectus transpositions in Duane syndrome with moderate or severe clinical signs have only been effective in a small percentage of the cases. Most of them required further surgeries to resolve the complications or the under-corrections

Association of lateral rectus muscle volume and ocular motility with the abducens nerve in Duane's retraction syndrome.

PURPOSE: To investigate the relationship between ocular motility and lateral rectus (LR) muscle volume according to the presence or absence of the abducens nerve in patients with Duane's retraction syndrome (DRS) using high-resolution magnetic resonance imaging (MRI). METHODS: A total of 54 unilateral DRS patients were divided into two groups according to high-resolution MRI findings: DRS without an abducens nerve on the affected side (absent CN6 group, n = 45) and DRS with symmetric abducens nerves on both sides (present CN6 group, n = 9). Ocular motility was measured by image analysis based on nine gaze photographs. LR volume was measured on T2-weighted coronal MRI of the orbit, and the ratio of paretic/normal side (P/N) LR volume was investigated. Association of the abducens nerve with various parameters including ocular motility, LR volume, and ratios of P/N LR volume were determined. RESULTS: LR volume was smaller in the affected eye than the non-affected eye in both groups. In the present CN6 group, abducens nerve diameter and the ratio of P/N LR volume showed a positive correlation. A smaller LR volume and more limitation of abduction in the affected eye were predictive of an absent abducens nerve in DRS. CONCLUSIONS: LR muscle hypoplasia was apparent in the affected eye of DRS patients. Abducens nerve diameter positively correlated with the ratio of P/N LR volume in the present CN6 group. Graphical abstract.

Effect of lateral rectus muscle resection on abduction in Duane retraction syndrome type 1.

PURPOSE: To assess the effect of lateral rectus muscle resection on abduction in Duane retraction syndrome (DRS) type 1. METHODS: The medical records of patients with DRS type 1 were reviewed retrospectively. Fifteen patients who underwent lateral rectus resection were included. Prism and cover test and the Krimsky test were used to detect deviations. Ocular ductions, abnormal head position (AHP), and globe retraction were recorded. RESULTS: Nine (60.0%) patients were female. The mean age was 13.1 ± 2.3 (range, 2-34) years. Left eyes were included in ten (66.7%) patients. Mean follow-up time was 37.6 ± 16.6 (range, 6-70) months. All patients had AHP, 13 patients had mild globe retraction, and 2 patients had no globe retraction preoperatively. Mean lateral rectus resection was 3.1 ± 0.7 (range, 2.0-4.5) mm, and the mean medial rectus recession was 4.4 ± 0.6 (range, 3.0-5.0) mm. The mean preoperative deviation decreased from 23.3 ± 6.9 (range, 14-35) prism diopters (pd) to 2.2 ± 4.1 (range, 0-10) pd at near, and from 23.6 ± 7.1 (range, 14-35) pd to 1.8 ± 3.5 (range, 0-10) pd at distance, at 6 months postoperatively (p = 0.01). The mean limitation in abduction decreased from - 3.2 ± 0.9 to - 1.3 ± 1.1 postoperatively (p < 0.001). AHP resolved in all patients. There was not a limitation in adduction or a worsening of globe retraction in any patient. CONCLUSION: Lateral rectus resection can be used to improve abduction in patients with DRS type 1 who have mild globe retraction. We assume that this procedure has no worsening effect on globe retraction in appropriate cases.

Ocular structural changes in patients with Duane retraction syndrome: Does a correlation exist?

PURPOSE: The purpose of this study was to investigate the structural changes (axial length, central macular thickness (CMT), subfoveal choroidal thickness, and keratometry) in subjects with unilateral Duane retraction syndrome (DRS) as compared with the normal fellow eye. METHODS: In this prospective study, we included 34 subjects with unilateral DRS from January 2016 to December 2016 seen at our institute. Data was collected for axial length, keratometry using partial coherence interferometry, CMT, subfoveal choroidal thickness using the enhanced depth imaging-optical coherence tomography (EDI-OCT). All these measurements were compared between the affected and fellow eye. RESULTS: During this period, we included 34 subjects with unilateral DRS (22 Type I, 1 Type II, and 11 Type III). The mean age (±SD) of subjects was 14 ± 8 years (range: 5-28 years). There were 15 males and 19 females. Eyes with DRS were significantly shorter (median axial length 22.4 mm, interquartile range (IQR): 21.56 - 23.17) as compared to fellow eye (median axial length 22.7 mm, IQR: 22.35-23.55), P = 0.04. Choroidal thickness, CMT, and average keratometry were similar in DRS and fellow eyes (P = 0.39, 0.06, and 0.11, respectively). A significant difference in axial length was found only between Type I and Type III DRS (P = 0.03). CONCLUSION: This study suggests that in subjects with DRS, the affected eye has shorter median axial length when compared with the fellow eye. Prevalence of refractive error in eye with DRS was higher compared to fellow eye. But, there was no difference in magnitude of refractive error found between eye with DRS and normal fellow eye.