Epiretinal membrane: a treatable cause of visual disability in myotonic dystrophy type 1

Retinal vascular abnormalities in myotonic dystrophy assessed by optical coherence tomography angiography - Cross-sectional study

BACKGROUND

The aim of the study was to detect the changes in retinal and choroidal vasculature via optical coherence tomography angiography (OCTA) by comparing the quantitative OCTA parameters in patients with and without myotonic dystrophies (DM).

MATERIAL

The cross-sectional study. Forty-one consecutive patients affected by DMs were enrolled. The inclusion criteria were molecular diagnosis of DM types 1 and 2. To avoid the age effect on microvascular changes and to justify a comparison between DM1 and DM2 patients, two control groups matched for sex and age were established.

RESULTS

The vascular density was found to be significantly decreased in the DM groups compared to the controls in the macular, parafoveal and perifoveal zone of superficial capillary plexus (p < 0.001 for the DM1 group, and p = 0.001, p = 0.005 and p = 0.026, respectively, for the DM2 group), as well as in the macular zone in the deep capillary plexus for DM1 (p = 0.002) and deep macular and perifoveal zone for DM2 (p = 0.007, p = 0.001, respectively). The foveal avascular zone showed no significant differences between DM1 and DM2 compared to their control groups (p = 0.320 and p = 0.945, respectively).

CONCLUSION

Our results show that DM is associated not only with the classic pigmentary changes but also with superficial and deep retinal microvasculature abnormalities, suggesting that these changes may be related to local hypoperfusion. Optical coherence tomography angiography is a useful tool for the diagnosis and characterization of retinal changes in DM and should be part of the standard evaluation of these patients.

Ocular findings in a Spanish cohort of myotonic dystrophy type 1

PURPOSE

Myotonic dystrophy type 1 is the most common muscular dystrophy in adulthood, caused by a triplet repeat in chromosome 19q13.3. The present study investigates the frequency of the different ocular alterations in Spanish patients with DM1 and its relationship with the severity of the genetic alteration.

METHODS

Cross-sectional and multicenter study was conducted on patients with genetically confirmed DM1. Ophthalmologic examinations included visual acuity assessment, manifest refraction, slit-lamp biomicroscopy, tonometry, ocular motility, corneal tomography, and macular and optic nerve optical coherence tomography.

RESULTS

A total of 42 patients (84 eyes) were included. Mean age was 46.9 ± 13.4 (SD) years, and 57.1% were women. Fifteen patients had undergone cataract surgery in at least one eye (35.7%), and 13 (30.9%) had significant cataract. Mean intraocular pressure (IOP) was 10.5 ± 2.9 mmHg, and mean central corneal thickness (CCT) was 580.04 ± 48.61 μm. Half of the patients had significant ptosis, and 8 patients (9.75%) had undergone eyelid surgery. Macular abnormalities included retinal pigment epithelium alterations in 8 eyes of 6 patients, epiretinal membrane in 3 eyes, and lamellar hole in 2 eyes. A moderate correlation was found between IOP and ptosis with the number of triplet repeats.

CONCLUSION

Early cataract onset, low IOP, thicker CCT, and ptosis were the most significant manifestations of DM in our sample. Correlation found between IOP and ptosis with CTG repeat could be interesting in order to improve diagnosis and medical care of these patients but should be confirmed in further studies.

Characteristics of myotonic dystrophy patients in the national registry of Japan

Myotonic dystrophies (DM) are inherited autosomal dominant disorders affecting multiple organs. Currently available therapeutics for DM are limited; therefore, a patient registry is essential for therapeutic development and success of clinical trials targeting the diseases. We have developed a nationwide DM registry in Japan under the Registry of Muscular Dystrophy (Remudy). The registration process was patient-initiated; however, physicians certified the clinical information. The dataset includes all Naarden and TREAT-NMD core datasets and additional items covering major DM clinical features. As of March 2020, we enrolled 976 patients with genetically confirmed DM. The majority (99.9%) of these patients had DM1, with 11.4% having the congenital form. However, 1 patient had DM2. Upon classifying 969 symptomatic DM1 patients based on their age at onset, an earlier onset was associated with a longer CTG repeat length. Myotonia was the most frequent symptom, followed by hand disability, fatigue, and daytime sleepiness. The frequency of hand disabilities, constipation, and visual disturbances was higher for patients with congenital DM. According to a multiple regression analysis of objective clinical measurements related to prognosis and activities of daily living, CTG repeat length strongly influenced the grip strength, forced vital capacity, and QRS time in an electrocardiogram. However, the grip strength was only modestly related to disease duration. This report will shed light on the Japanese national DM registry, which has recruited a significant number of patients. The registry will provide invaluable data for planning clinical trials and improving the standard of care for patients.

Spectral domain optical coherence tomography findings in myotonic dystrophy

The purpose of the study is to evaluate retinal involvement in a cohort of patients affected by Myotonic Dystrophy type 1 (DM1). Both eyes of 30 patients and one eye of a 31st patient with genetically proven diagnosis of DM1 and both eyes of 20 healthy age- and gender-matched subjects were enrolled. All patients underwent complete ophthalmologic examination including best-corrected visual acuity, intraocular pressure measurement, fundoscopy, fundus autofluorescence, infrared imaging and spectral-domain optical coherence tomography with central macular thickness measurement. DM1 patients showed statistically significant higher central macular thickness values than controls. In the DM1 group, butterfly (14.8%) and reticular (13.1%) pigment abnormalities were found with corresponding drusenoid deposit and focal disruption of photoreceptor and retinal pigment epithelium layers. Compared with the controls, DM1 group had higher prevalence of epiretinal membrane. In the DM1 group, the prevalence of epiretinal membrane and retinal pigment epithelium alterations were directly correlated with age, whereas no correlation was found with disease duration, CTG expansion and MIRS score. In conclusion, in addition to the typical retinal pigment epithelium changes, DM1 is also associated with abnormalities of the vitreoretinal interface, particularly epiretinal membrane, resulting in central macular thickness increase. Both inner and outer retinal alterations were associated with increasing age, suggesting that DM1 may cause a premature aging of the retina.

The New Zealand Neuromuscular Disease Patient Registry; Five Years and a Thousand Patients

The New Zealand Neuromuscular Disease Patient Registry has been recruiting for five years. Its primary aim is to enable people with neuromuscular disease to participate in research including clinical trials. It has contributed data to large anonymised cohort studies and many feasibility studies, and has provided practical information and advice to researchers wanting to work with people with neuromuscular conditions. 1019 people have enrolled since the Registry's launch in August 2011 with over 70 different diagnoses. Of these; 8 patients have been involved in clinical trials, 134 in other disease-specific research and 757 have contributed anonymised data to cohort studies. As a result the Registry is now effectively facilitating almost all neuromuscular research currently taking place in New Zealand.

Retinal Imaging of Infants on Spectral Domain Optical Coherence Tomography

Spectral domain coherence tomography (SD OCT) has become an important tool in the management of pediatric retinal diseases. It is a noncontact imaging device that provides detailed assessment of the microanatomy and pathology of the infant retina with a short acquisition time allowing office examination without the requirement of anesthesia. Our understanding of the development and maturation of the infant fovea has been enhanced by SD OCT allowing an in vivo assessment that correlates with histopathology. This has helped us understand the critical correlation of foveal development with visual potential in the first year of life and beyond. In this review, we summarize the recent literature on the clinical applications of SD OCT in studying the pathoanatomy of the infant macula, its ability to detect subclinical features, and its correlation with disease and vision. Retinopathy of prematurity and macular edema have been discussed in detail. The review also summarizes the current status of SD OCT in other infant retinal conditions, imaging the optic nerve, the choroid, and the retinal nerve fibre in infants and children, and suggests future areas of research.

Ophthalmic manifestations of inherited neurodegenerative disorders

Ophthalmic findings are common features of neurodegenerative disorders and, in addition to being clinically important, have emerged as potentially useful biomarkers of disease progression in several conditions. Clinically, these visual system abnormalities can be a clue to diagnosis, as well as being a prominent cause of disability in affected patients. In this Review, we describe the various afferent visual system and other ophthalmic features of inherited neurodegenerative disorders, including the muscular dystrophies, Friedreich ataxia, the spinocerebellar ataxias, hereditary spastic paraplegia, Charcot-Marie-Tooth disease, and other conditions. We focus on the expanding role of optical coherence tomography in diagnostic imaging of the retina and optic nerve head, and the possible use of ophthalmic findings as biomarkers of disease severity in hereditary neurodegenerative disorders. In addition, we discuss the ophthalmic manifestations and treatment implications of mitochondrial dysfunction, which is a feature of many inherited neurodegenerative diseases.