The Structural Abnormalities Are Deeply Involved in the Cause of RPGRIP1-Related Retinal Dystrophy in Japanese Patients.

Leber congenital amaurosis (LCA) is the most severe form of inherited retinal dystrophy. RPGRIP1-related LCA accounts for 5-6% of LCA. We performed whole-exome sequencing and whole-genome sequencing (WGS) on 29 patients with clinically suspected LCA and examined ophthalmic findings in patients with biallelic pathogenic variants of RPGRIP1. In addition to five previously reported cases, we identified five cases from four families with compound heterozygous RPGRIP1 variants using WGS. Five patients had null variants comprising frameshift variants, an Alu insertion, and microdeletions. A previously reported 1339 bp deletion involving exon 18 was found in four cases, and the deletion was relatively prevalent in the Japanese population (allele frequency: 0.002). Microdeletions involving exon 1 were detected in four cases. In patients with RPGRIP1 variants, visual acuity remained low, ranging from light perception to 0.2, and showed no correlation with age. In optical coherence tomography images, the ellipsoid zone (EZ) length decreased with age in all but one case of unimpaired EZ. The retinal structure was relatively preserved in all cases; however, there were cases with great differences in visual function compared to their siblings and a 56-year-old patient who still had a faint EZ line. Structural abnormalities may be important genetic causes of RPGRIP1-related retinal dystrophy in Japanese patients, and WGS was useful for detecting them.

The first USH2A mutation analysis of Japanese autosomal recessive retinitis pigmentosa patients: a totally different mutation profile with the lack of frequent mutations found in Caucasian patients.

Retinitis pigmentosa (RP) is a highly heterogeneous genetic disease. The USH2A gene, which accounts for approximately 74-90% of Usher syndrome type 2 (USH2) cases, is also one of the major autosomal recessive RP (arRP) causative genes among Caucasian populations. To identify disease-causing USH2A gene mutations in Japanese RP patients, all 73 exons were screened for mutations by direct sequencing. In total, 100 unrelated Japanese RP patients with no systemic manifestations were identified, excluding families with obvious autosomal dominant inheritance. Of these 100 patients, 82 were included in this present study after 18 RP patients with very likely pathogenic EYS (eyes shut homolog) mutations were excluded. The mutation analysis of the USH2A revealed five very likely pathogenic mutations in four patients. A patient had only one very likely pathogenic mutation and the others had two of them. Caucasian frequent mutations p.C759F in arRP and p.E767fs in USH2 were not found. All the four patients exhibited typical clinical features of RP. The observed prevalence of USH2A gene mutations was approximately 4% among Japanese arRP patients, and the profile of the USH2A gene mutations differed largely between Japanese patients and previously reported Caucasian populations.

Interaction between optineurin and the bZIP transcription factor NRL.

Although the gene encoding optineurin (OPTN) is a causative gene for glaucoma and amyotrophic lateral sclerosis, it is ubiquitously expressed in all body tissues, including the retina. To study the function of OPTN in retinal ganglion cells as well as the whole retina, we previously isolated OPTN-interacting proteins and identified the gene encoding the bZIP transcription factor neural retina leucine zipper (NRL), which is a causative gene for retinitis pigmentosa. Herein, we investigated the binding between OPTN and NRL proteins in HeLaS3 cells. Co-expression of HA-tagged NRL and FLAG-tagged OPTN in HeLaS3 cells followed by immunoprecipitation and Western blotting with anti-tag antibodies demonstrated the binding of these proteins in HeLaS3 cells, which was confirmed by proximity ligation assay. NRL is the first OPTN-binding protein to show eye-specific expression. A series of partial-deletion OPTN plasmids demonstrated that the tail region (423-577 amino acids [aa]) of OPTN was necessary for binding with NRL. Immunostaining showed that Optn (rat homologue of OPTN) was expressed in rat photoreceptors and localised in the cytoplasm of photoreceptor cells. This is a novel demonstration of Optn expression in photoreceptor cells. OPTN was not detected in photoreceptor nuclei under our experimental conditions. Further analyses are necessary to elucidate the function of OPTN and the significance of its possible binding with NRL in photoreceptor cells.

Intraocular pressure changes at different gaze positions after superior rectus muscle-lateral rectus muscle loop myopexy in highly myopic strabismus.

PURPOSE: To evaluate changes in intraocular pressure (IOP) at different gaze positions before and after superior rectus muscle-lateral rectus muscle (SR-LR) loop myopexy in highly myopic strabismus (HMS). STUDY DESIGN: Nonrandomized clinical, prospective, interventional trial. METHODS: Fourteen patients with HMS (18 eyes) who underwent SR-LR loop myopexy were divided into 3 groups: < 100 prism diopters (PD) (mild esotropia [ET] group), > 100 PD (large ET group), and > 100 PD, and simultaneous recession of the medial rectus (MR) muscle was performed (large ET + MR group). Intraocular pressure was measured preoperatively and postoperatively at the primary, abduction, and adduction positions in each group. RESULTS: Intraocular pressure did not change after surgery in the mild ET group. Intraocular pressure significantly decreased in the abduction position (from 20.0 ± 2.1 to 16.0 ± 1.9 mmHg, P = 0.043) in the large ET group and in the abduction (from 22.2 ± 5.9 to 15.6 ± 4.3 mmHg, P = 0.048) and primary positions (from 15.8 ± 5.0 to 10.2 ± 2.8 mmHg, P = 0.043) in the large ET + MR group. The preoperative significant differences in IOP between the abduction and adduction positions in the large ET group (7.4 ± 3.4 mmHg) and the large ET + MR group (10.0 ± 5.5 mmHg) disappeared postoperatively (3.2 ± 2.8 mmHg and 3.6 ± 1.7 mmHg, respectively). The differences in IOP between abduction and adduction were similar in all the groups. CONCLUSION: SR-LR loop myopexy decreased IOP in patients with HMS in the abduction and primary positions.

Recovery of stereoacuity after Yokoyama procedure in patients with highly myopic strabismus with good vision.

Purpose: To report stereopsis after bilateral Yokoyama procedure in patients with highly myopic strabismus and good visual acuity. Observations: Five patients aged between 34 and 81 years with best-corrected visual acuity of 20/25 or better were operated on. The preoperative strabismus angle ranged from esotropia of 35-113 prism diopters (PD) at distance and esotropia of 40-113 PD at near. One patient had left hypotropia of 4 PD and excyclotorsion of 15°, and the other had left hypotropia of 10 PD. Their axial lengths were 27.65-33.07 mm, and the posterior globe dislocation angles were between 123 and 148° on coronal magnetic resonance imaging (MRI). Limitations of abduction were between -1 and -2. All patients complained of diplopia, and none of them showed stereopsis. The Yokoyama procedure was performed on both eyes. Postoperative alternate cover testing showed from esotropia of 2 PD to exophoria of 8 PD at distance and from exotropia of 12 PD to esophoria of 10 PD at near.Three patients recovered stereopsis of 100, 50, and 140 sec, respectively. Two cases required unilateral inferior rectus muscle recessions, and their postoperative stereopsis was 25 and 50 sec. Conclusions and Importance: The Yokoyama procedure is effective not only in cases of heavy eye syndrome but also in cases of myopic esotropia associated with a globe dislocation angle of 120° or with little abduction restriction. If visual acuity is good, stereopsis may be restored with improvement in eye deviation.

A case of siblings with juvenile retinitis pigmentosa associated with NEK1 gene variants.

BACKGROUND: Axial spondylometaphyseal dysplasia(axial SMD) is associated with early-onset retinal dystrophy and various skeletal dysplasias of varying severity. NEK1 is the causative gene for short rib polydactyly syndrome and axial SMD. Here, we report a case of siblings with juvenile retinitis pigmentosa (RP) and NEK1 variants not associated with systemic disorders. MATERIALS AND METHODS: The patients were a 7-year-old-girl and a 9-year-old boy with RP, who were followed for 9 years. Whole exome sequencing (WES) was performed on the siblings and their parents, who were not consanguineous. RESULTS: The corrected visual acuity of the girl and the boy at first visit was binocular 20/63 and 20/100 OD and 20/63 OS, respectively. The siblings had narrowing of retinal blood vessels and retinal pigment epithelium atrophy in the fundus and showed an extinguished pattern in electroretinogram. On optical coherence tomography, there was a mottled ellipsoid band with progressive loss in the outer macular, the edges of which corresponded to the ring of hyperautofluorescence on fundus autofluorescence imaging. The siblings showed progressive visual field constriction. Radiological examination did not reveal any skeletal abnormalities. We identified two rare heterozygous NEK1 variants in the patients: c.240 G>A; p.(M80I) and c.634_639dup;p.(V212_L213dup). Heterozygous variants were recognized in the father and mother, respectively. According to the guidelines of the American College of Medical Genetics and Genomics, both variants were classified as likely pathogenic. CONCLUSION: This is the first report of RP patients with NEK1 variants not associated with skeletal abnormalities.

Clinical presentations of acquired comitant esotropia in 5-35 years old Japanese and digital device usage: a multicenter registry data analysis study.

PURPOSE: To describe clinical presentations of acquired comitant esotropia and digital device use in children, adolescents, and young adults without neurological problems. STUDY DESIGN: Multicenter prospective observational study. METHODS: Patients with acquired comitant esotropia, without intracranial diseases aged 5-35 years at the time of visit, who were seen at pre-registered facilities within 1 year of onset were enrolled. The duration from the onset of symptoms and the time of digital device usage approximately 1 month before onset and their lifestyles were surveyed. Visual acuity, cycloplegic refraction, and strabismus angles were measured. Data were analyzed in three age groups (Child: 5-12 years, Adolescent: 13-18 years, and Young adult: 19-35 years). RESULTS: Between November 2019 and December 2021, 218 patients were enrolled from 55 facilities, and 194 patients (including 62 children, 69 adolescents, and 63 young adults) were analyzed. The child group spent the least amount of time using digital devices (children: 159; adolescents: 210; young adults: 267 min/work day, p < 0.05; (mean time in the same order below) 229, 338, 314 min/holiday, p < 0.05) and had the largest strabismus angle (mean strabismus angle at near: 30, 22, 18 PD, p < 0.01; at far: 28, 26, 21 PD, p<0.05). CONCLUSION: The clinical features of acquired comitant esotropia and hand-held digital device usage differed between children aged ≤ 12 years and older patients. This report gives the current clinical characteristics of young patients with acquired esotropia and digital device usage.

Medial Rectus Muscle Resection Versus Plication: A Comparison of Conjunctival-Scleral Thickness Measured by AS-OCT.

PURPOSE: To compare conjunctival-scleral thickness measured with anterior segment optical coherence tomography before and after medial rectus muscle resection and plication for exotropia. METHODS: In this prospective observational study, patients with exotropia aged 5 years and older who underwent medial rectus muscle resection or plication through limbal incision of the conjunctiva between April 2016 and June 2018 were enrolled. Conjunctivalscleral thickness was measured with anterior segment optical coherence tomography before and 3 and 6 months after surgery at 1.5 mm (limbus), 4 mm (insertion), and 5.5 mm (tendon) posterior to the scleral spur. One examiner made measurements twice blinded for the initial data. Conjunctival-scleral thickness was compared between groups using the Mann-Whitney U test. RESULTS: Twenty participants were divided into two groups: resection (n = 11) and plication (n = 9). The respective conjunctival-scleral thicknesses before and 3 and 6 months after surgery in the resection group were as follows: 0.76, 0.90, and 0.86 mm at the limbus; 0.86, 1.18, and 1.12 mm at the insertion; and 1.04, 1.41, and 1.33 mm at the tendon. Corresponding values in the plication group were as follows: 0.74, 0.87, and 0.81 mm at the limbus; 0.84, 1.16, and 1.08 mm at the insertion; and 1.00, 1.39, and 1.27 mm at the tendon. No between-group differences were observed at any location or time. CONCLUSIONS: No differences in conjunctival-scleral thickness were observed between the resection and plication groups before surgery or at 3 months and 6 months postoperatively. [J Pediatr Ophthalmol Strabismus. 2022;59(4):274-278.].

Clinical findings of acute acquired comitant esotropia in young patients.

PURPOSE: This study aimed to identify the characteristics of acute acquired comitant esotropia (AACE) in young patients from a single institution; and clarify their relationship with the excess use of digital devices. STUDY DESIGN: Retrospective, observational. METHODS: We extracted the clinical charts of patients aged between 5 and 35 years who presented at the Hamamatsu University Hospital with AACE symptoms from January 1, 2015 to December 31, 2018. The age of onset, angle of deviation, refractive errors, history of near work, including excess smartphone use, and treatment modality were retrieved. Patients were divided into three groups: CHILD (aged 5-12 years), JUNIOR (aged 13-17 years), and ADULT (aged 18-35 years) and statistically analyzed with Kruskal-Wallis test. RESULTS: Forty-one patients were retrieved, with a mean age at onset of 15.8 (5-28) years; eight in the CHILD group, 23 in the JUNIOR group, and 10 in the ADULT group. Refractive errors and age of patients were correlated, but were not significantly different among groups. The mean angle of deviation at distance was 28.0 ± 12.8 prism diopters (PD) and 28.6 ± 17.2 PD at near. The CHILD group showed the largest near-distant dissociation. History of excessive near work was found in all groups. CONCLUSION: AACE was most commonly found in the JUNIOR group, especially those aged 15-16 years. AACE may encompass multiple diseases; using common diagnostic criteria and asking common questions regarding digital device usage is necessary to clarify the influence of digital device usage, and a multicenter prospective study is recommended.

Exophthalmos associated with chronic progressive external ophthalmoplegia.

PURPOSE: Chronic progressive external ophthalmoplegia (CPEO) is a mitochondrial disease characterized by slowly progressive ptosis and limitations in ocular motility. Although exophthalmos is not considered to be a common feature of CPEO, this study focused on the incidence of exophthalmos in patients with CPEO. STUDY DESIGN: Retrospective observational case series METHODS: We reviewed the clinical charts of patients who received a diagnosis of CPEO sometime during the period between January 2010 and December 2018. CPEO was diagnosed on the basis of detection of a deletion of mitochondrial DNA (mtDNA) from saliva, buccal mucosa, or extraocular muscle specimens obtained during strabismus surgery. Horizontal MRI/CT images or Hertel ophthalmometry was used in determining exophthalmos. RESULTS: Seven patients (4 males) were identified. The mean age at diagnosis was 32.6 years (range 13-53 years). mtDNA deletion mutations were detected in the buccal mucous membrane DNA in 5 patients and in the saliva and extraocular muscle DNA in 2 patients. MRI/CT was recorded in 6 patients, four of whom showed exophthalmos (cases 1-4), and case 5 was determined as exophthalmos on the basis of a Hertel ophthalmometer reading. Exophthalmos was bilateral in 4 of the patients (cases 1, 2, 4, and 5) and unilateral in 1 patient (case 3). Exophthalmos was the chief concern of 2 of the patients; however, it was not clinically significant in the other patients. CONCLUSIONS: Although exophthalmos may not be recognized by either the patient or the clinician, it may be one of the common features of CPEO. A large multiethnic study should be performed.

Intraocular pressure at different gaze positions in patients with highly myopic strabismus.

PURPOSE: To evaluate intraocular pressure (IOP) at different gaze positions in patients with highly myopic strabismus (HMS). STUDY DESIGN: Nonrandomized, prospective, observational study. METHODS: This study included 18 eyes of 14 patients with HMS and 51 eyes of 51 age-matched controls without strabismus; these were further divided into two groups based on refractive errors: > -6.00 diopter (D) (n = 22 eyes) and ≤ -6.00 D (n = 29 eyes). IOP was measured in primary and side gazes and compared within and among groups. The relationships between IOPs and axial length, angle of globe dislocation measured on magnetic resonance imaging, strabismus angle, and degree of abduction deficit were studied. RESULTS: The HMS group showed higher IOP in abduction (19.3 ± 4.9 mmHg) than in the primary (12.5 ± 4.3 mmHg) and adducting positions (13.0 ± 3.3 mmHg), (p < 0.001). The IOP in the adducting position in the HMS group (13.0 ± 3.3 mmHg) was lower than in the control groups both with (17.6 ± 3.5 mmHg) and without (16.9 ± 4.1 mmHg) high myopia, ; (p < 0.001 and = 0.003). The difference in IOP between abduction and adduction was significantly larger in the HMS group (6.4 ± 4.6 mmHg) compared to others (p < 0.001) and positively correlated with the strabismus angle and the angle of globe dislocation and negatively with abduction deficit. CONCLUSION: The IOP of patients with HMS changes dramatically on side gazes, therefore, care should be taken while measuring IOP.

Two cases of acquired bilateral trochlea nerve palsy treated by simultaneous inferior rectus muscle nasal transposition and inferior oblique muscle myectomy.

PURPOSE: To report two cases of acquired bilateral trochlea nerve palsy with large torsional deviation successfully treated by simultaneous bilateral inferior rectus muscle (IR) nasal transposition and inferior oblique muscle (IO) myectomy. OBSERVATIONS: Case 1 was of a 54-year-old man with torsional diplopia after a traffic accident. He showed 32° and 38° excyclotorsion in the primary and downward gazes, respectively. Case 2 was of a 56-year-old woman with torsional diplopia after a brain tumor operation. She showed 25° and 33° excyclotorsion in the primary and downward gazes, respectively. We simultaneously performed bilateral IR nasal transposition and IO myectomy in these two cases. Postoperatively, case 1 presented with improved excyclotorsion, with 2° and 7° excyclotorsion in the primary and downward gazes, respectively; case 2 similarly presented with improved excyclotorsion, with 4° and 12° excyclotorsion in the primary and downward gazes, respectively. CONCLUSIONS AND IMPORTANCE: Simultaneous bilateral IR nasal transposition and IO myectomy are effective for treating large-angle torsional deviations, especially in downward gaze, requiring only one operation. A new surgical approach is suggested for the successful treatment of large torsional deviations, requiring only one operation.

Effects of the Gaze Fixation Position on AS-OCT Measurements of the Limbus and Extraocular Muscle Insertion Site Distance.

PURPOSE: To investigate the effect of the gaze fixation position on measurement of the limbus and extraocular muscle (EOM) insertion site distance using anterior segment optical coherence tomography (AS-OCT). METHODS: Patients undergoing horizontal EOM surgeries were enrolled in this prospective experimental study. The distance between the angle recess and the muscle insertion site was measured using AS-OCT while patients fixed their gaze laterally or medially at inner or outer gaze fixation. The distance between the limbus and muscle insertion was intraoperatively measured using calipers. RESULTS: A total of 46 lateral rectus muscles and 36 medial rectus muscles of 44 patients were evaluated. Significant differences were observed between intra-operative measurements (6.3 ± 0.7 mm) and AS-OCT measurements (5.8 ± 0.7 mm) for the lateral rectus muscle at inner gaze fixation (P = .0017) and medial rectus muscle at outer gaze fixation (P = .0003); no difference was observed when the lateral rectus (6.4 ± 0.5 mm) and medial rectus (4.9 ± 0.6 mm) muscles were measured at outer and inner gaze fixation, respectively. Bland-Altman plots showed better consistency at outer gaze fixation than at inner gaze fixation for the lateral rectus muscle; the opposite was observed for the medial rectus muscle. More than 80% of the AS-OCT measurements were within 1 mm of the intraoperative measurements at outer gaze fixation for the lateral rectus muscle and inner gaze fixation for the medial rectus muscle. CONCLUSIONS: Gaze fixation at outer gaze fixation for the lateral rectus muscle and inner gaze fixation for the medial rectus muscle was an appropriate technique to assess limbus and EOM insertion using AS-OCT. [J Pediatr Ophthalmol Strabismus. 2021;58(1):28-33.].

Usefulness of handheld electroretinogram system for diagnosing blue-cone monochromatism in children.

PURPOSE: To report the diagnosis of three childhood patients with blue-cone monochromatism (BCM) using S-cone electroretinograms (ERG) recorded with RETeval® Complete. STUDY DESIGN: Prospective clinical study. METHODS: We examined three boys initially suspected of having rod monochromatism. S-cone ERG was performed with red background and blue flashed light stimulation using two different intensities: 0.25 cd × s/m2 and 1 cd × s/m2. RESULTS: Case 1 was a 12-year-old boy with a visual acuity of 0.1 OU. Case 2 was an 8-year-old boy with a visual acuity of 0.3 OD and 0.2 OS. Both cases showed a myopic fundus and nystagmus without any other ocular abnormalities. Case 3 was a 6-year-old boy with a visual acuity of 0.3 OD and 0.4 OS. He also showed myopic fundus changes, but nystagmus was not observed. Rod and maximal responses recorded with RETeval® were likely to be within normal range; however, cone responses were absent in all cases. S-cone ERGs showed positive responses at 40 ms with 0.25 cd × s/m2 intensity in Case 2, and at approximately 30-40 ms with 1.0 cd × s/m2 intensity in all three cases. These ERG findings led to a diagnosis of BCM. CONCLUSIONS: S-cone ERG of RETeval® was helpful in diagnosing with minimal invasion BCM in childhood patients.

Magnetic resonance imaging of the medial rectus muscle of patients with consecutive exotropia after medial rectus muscle recession.

PURPOSE: To investigate the morphologic characteristics of the medial rectus muscle in patients with consecutive exotropia. DESIGN: Retrospective, nonrandomized, interventional study. PARTICIPANTS AND CONTROLS: Eleven eyes of 10 patients with consecutive exotropia were studied. Thirteen eyes of 13 age-matched normal subjects were studied as controls. METHODS: All of the patients underwent an advancement of a previously operated medial rectus muscle. Patients were divided into 3 groups based on the insertion of the medial rectus muscle: Normally recessed stretched scar, and slipped muscle. MAIN OUTCOME MEASURES: A comparison was made of the clinical findings, intraoperative findings, and distance from the limbus to the medial rectus muscle measured on magnetic resonance images among the groups. RESULTS: The medial rectus of 4 eyes of 3 patients had normally recessed insertions and 7 eyes had abnormal insertions (3 stretched scars, 4 slipped muscles). The clinical findings were not different among the 3 groups. The magnetic resonance images showed that the medial rectus muscle was located closest to the limbus in the control subjects and most distant in the patients with a slipped muscle (P<0.005). The clinical findings in the patients with a stretched scar and with normally recessed were indistinguishable. CONCLUSIONS: Magnetic resonance images of the medial rectus muscles of the control subjects and operated groups are significantly different morphologically. A slipped medial rectus muscle has characteristic magnetic resonance findings that are distinguishable from the muscle with normally recessed and stretched scar.

A case of childhood glaucoma with a combined partial monosomy 6p25 and partial trisomy 18p11 due to an unbalanced translocation.

Background: Chromosomal deletion involving the 6p25 region results in a clinically recognizable syndrome characterized by anterior eye chamber anomalies with risk of glaucoma and non-ocular malformations (6p25 deletion syndrome). We report a newborn infant case of childhood glaucoma with a combination of partial monosomy 6p25 and partial trisomy 18p11 due to an unbalanced translocation.Materials and methods: The patient was a 0-year-old girl. Both eyes showed aniridia and left eye Peters anomaly with multiple malformations. To identify the chromosomal aberrations in the patient with clinically suspected 6p25 deletion syndrome, we performed cytogenetic analysis (G-banding and multicolor fluorescent in-situ hybridization) and array-based comparative genomic hybridization (array-CGH) analysis.Results: Cytogenetic analyses revealed a derivative chromosome 6 with its distal short arm replaced by an extra copy of the short arm of chromosome 18. Array-CGH analysis detected a 4.6-Mb deletion at 6pter to 6p25.1 and 8.9-Mb duplication at 18pter to 18p11.22. To determine the breakpoint of the unbalanced rearrangement at the single-base level, we performed a long-range PCR for amplifying the junctional fragment of the translocation breakpoint. By sequencing the junctional fragment, we defined the unbalanced translocation as g.chr6:pter_4594783delinschr18:pter_8911541.Conclusions: A phenotype corresponding to combined monosomy 6p25 and trisomy 18p11 presented as childhood glaucoma associated with non-acquired (congenital) ocular anomalies consist of aniridia and Peters anomaly and other systemic malformations. To the best of our knowledge, this is the first report which demonstrated the breakpoint sequence of an unbalanced translocation in a Japanese infant with childhood glaucoma.

Superior oblique palsy with class III tendon anomaly.

PURPOSE: To describe the clinical findings and surgical results of superior oblique palsy with class III tendon anomaly. DESIGN: Observational case series. METHODS: One hundred and forty-one cases of congenital and idiopathic superior oblique palsy were operated on by one surgeon (M.S.) between September 1, 1995 and August 31, 2007. The superior oblique tendons were explored in 26 cases. Among these, five cases were found to have the distal end of the tendon inserted into the Tenon capsule. Preoperative eye alignment, visual acuity, stereopsis measured with Titmus stereo acuity tests (Stereo Fly SO-001; Stereo Optical Co, Chicago, Illinois, USA), and magnetic resonance imaging findings were collected from the patients' records. Main outcome measures included preoperative eye position, surgical results, and stereoscopic acuity. Stereopsis and the amount of vertical deviation were compared in cases with class I, II, and IV tendon anomalies. RESULTS: A total of eight surgeries were performed on five patients with class III superior oblique tendon anomaly. Three muscles were operated on for each patient. The amount of vertical deviation was not significantly different from other types of tendon anomaly. Patients with class I to III tendon anomalies obtained good stereopsis after strabismus surgery, whereas cases with class IV anomaly achieved only limited stereopsis. The number of surgeries performed was significantly higher in cases with class IV anomaly. CONCLUSIONS: Without careful search of the Tenon capsule, the condition can be misdiagnosed as an absent tendon. Strengthening the superior oblique tendon in the Tenon capsule can improve the alignment significantly.

Changes in conjunctival-scleral thickness after strabismus surgery measured with anterior segment optical coherence tomography.

PURPOSE: To evaluate changes in conjunctival-scleral thickness following strabismus surgery with anterior segment optical coherence tomography (AS-OCT). STUDY DESIGN: Prospective, observational, consecutive case series. METHODS: Distances between the conjunctival epithelium and inner scleral wall were measured with AS-OCT before and 3-5 months after strabismus surgery. The measurements were performed at 1.5 mm (limbus), 7.0 mm (insertion), and 8.0 mm (tendon) posterior to the scleral spur on the lateral rectus muscle (LR); and 1.5 mm (limbus), 4.0 mm (insertion), and 5.5 mm (tendon) posterior to the scleral spur on the medial rectus muscle (MR). Thirty-three extraocular muscles (20 LRs and 13 MRs) from 23 subjects were studied. RESULTS: Thicknesses were significantly less at the insertion (0.95-0.78 mm; p < 0.001) and tendon (0.99-0.78 mm; p < 0.001) after LR recession and at the tendon (1.21-0.92 mm; p = 0.02) after MR recession. Thicknesses were significantly greater at the insertion (0.82-1.07 mm; p = 0.01) and tendon (0.95-1.28 mm; p = 0.01) after MR resection or plication and at the limbus, insertion, and tendon (0.75-0.90 mm, 0.94-1.19 mm, 1.03-1.28 mm, respectively; all p = 0.04) after LR resection or plication. CONCLUSION: Conjunctival-scleral thicknesses showed various changes after recession and resection or plication. These findings may help detect previous surgical operations when conjunctival scarring and ciliary vessel changes are unclear.

Clinical characteristics of a Japanese patient with Bardet-Biedl syndrome caused by BBS10 mutations.

PURPOSE: Bardet-Biedl syndrome (BBS) is a rare autosomal recessive disorder characterized by retinal dystrophy, renal dysfunction, central obesity, mental impairment, polydactyly, and hypogonadism. Only limited information on BBS is available from Japanese patients. In addition, there are currently no reports of Japanese patients with BBS caused by BBS10 mutations. The purpose of this study was to present the characteristics of a Japanese patient with BBS caused by BBS10 mutations. PATIENT AND METHODS: The patient was a 22-year-old Japanese woman. Comprehensive ophthalmic examinations, including visual acuity measurements, perimetry, electroretinography (ERG), fundus autofluorescence imaging, and optical coherence tomography, were performed. Trio-based whole-exome sequencing was performed to identify potential pathogenic mutations, confirmed by Sanger sequencing. RESULTS: The patient showed neither renal malformation nor dysfunction, and visual impairment seemed to be relatively mild for BBS. The fundus examination revealed diffuse retinal degeneration without pigmentary deposits, and ERG scans showed undetectable responses. She had a history of surgically corrected polydactyly, and displayed symptoms of obesity. There was also a menstrual irregularity that could require progestin administration. Genetic analysis revealed compound heterozygous BBS10 mutations in the patient: a novel missense mutation c.98G>A [p.(G33E)], and a novel nonsense mutation c.2125A>T [p.(R709*)]. CONCLUSION: To our knowledge, this is the first description of a Japanese patient with BBS caused by BBS10 mutations. The clinical characteristics of our patient were mild, as neither renal impairment nor legal blindness was observed. Early diagnosis would play a role in providing counseling, and in some cases, therapeutic interventions for BBS patients.

Visual Outcomes in Japanese Patients with Retinitis Pigmentosa and Usher Syndrome Caused by USH2A Mutations.

PURPOSE: EYS and USH2A are the most common causative genes for retinitis pigmentosa (RP) in Japan. We determined the clinical outcomes for USH2A-related non-syndromic RP or Usher syndrome type II (USH2). METHODS: Two non-syndromic RP and 11 USH2 patients with previously identified USH2A mutations were included. Their complete history and medical records were collected using standard procedures. Visual fields and acuity were compared with those of patients with EYS mutations. Clinical analyses were based on ophthalmic and otolaryngologic examinations. RESULTS: In all patients, the fundus displayed changes typical of RP. Most patients showed relatively well-preserved visual acuity in their thirties or forties, with rapid deterioration in their fifties. Concentric constriction started in the twenties or thirties, and no effective residual visual field was observed after the fifties. CONCLUSIONS: The visual outcome for non-syndromic RP or USH2 patients with USH2A mutations is consistent with that for RP patients with EYS mutations.