Assessment of the Retinal Nerve Fibre Layer, Retina, and Choroid in Osteogenesis Imperfecta

BACKGROUND

Osteogenesis imperfecta (OI) is a genetic disorder in which there are problems in tissues containing type I collagen, predominantly the cornea and sclera in the eye. Although there are many studies on problems with the anterior segment of the eye in patients with OI, studies on posterior structures are limited. Involvement of the sclera may affect the retinal nerve fibre layer (RNFL), which is indirectly related to intraocular pressure. In addition, the retina and choroid containing type I collagen may be affected. The aim of the study was to compare the posterior segment structures of the eye, including the RNFL, retina, and choroid, in patients with OI to those of healthy control subjects.

METHODS

This cross-sectional study recruited 19 patients with OI, as well as 22 age- and gender-similar healthy control subjects. Measurements of the RNFL, retina, and choroid were obtained with optical coherence tomography (Spectralis SD-OCT, Heidelberg Engineering, Heidelberg, Germany).

RESULTS

Patients with OI (mean age 14.32 ± 5.08 years) and the control group (mean age 13.73 ± 3.56 years) had similar age, refractive error, and intraocular pressure values (p > 0.05). There was no difference between groups in terms of RNFL thickness, including the superonasal, nasal, inferonasal, inferotemporal, temporal, and superotemporal sectors, retinal thickness, and choroidal thickness from five different locations (p > 0.05, for all).

CONCLUSION

According to these results, OI does not clinically affect the RNFL, retina, and choroid in childhood.

Ophthalmological screening guidelines for individuals with Osteogenesis Imperfecta: a scoping review

BACKGROUND

Osteogenesis imperfecta (OI) is a connective tissue disorder in which the Type 1 collagen is defective. The eye is a structure rich in collagen Type 1 and is heavily impacted by the disease. Many vision-threatening eye diseases have been associated with OI. The onset of these diseases also tend to occur at an earlier age in individuals with OI. Despite the research on these risks, appropriate ophthalmological screening or care guidelines for individuals with OI remain unknown. As such, the purpose of this scoping review was to explore and describe existing ophthalmological screening and care guidelines to orient OI patient care.

MAIN BODY

A scoping review based on the Joanna Briggs Institute (JBI) methodology was conducted. A search of databases (PubMed and Medline) was completed in consultation with a research librarian. A total of 256 studies were imported for screening. Primary sources matching the inclusion and exclusion criteria were screened, extracted, and analyzed using Covidence.

CONCLUSION

A total of 12 primary articles met inclusion and exclusion criteria, containing case reports, case series and cohort studies. Despite the risk of blindness associated with the consequences of OI on the eye, the primary literature fails to provide detailed screening and care guidelines aimed at identifying disease early. We provide general recommendations based on the review findings to guide the ophthalmological care of patients with OI and call upon the experts to convene globally to create screening guidelines. Further investigations of ophthalmological screening are warranted to limit these vision-threatening risks with early detection and treatment. Standardized ophthalmological screening guidelines for OI remain an area for research.

Keratoconus tomographic indices in osteogenesis imperfecta

PURPOSE

Osteogenesis imperfecta (OI) is a rare inherited disease affecting collagen-rich tissues. Ocular complications have been reported such as thin corneas, low ocular rigidity, keratoconus, among others. The purpose of this study is to characterize corneal tomographic features in OI patients compared to unaffected patients, with particular focus on commonly studied keratoconus indices.

METHODS

Cross-sectional case-control study including 37 OI patients and 37 age-matched controls. Patients and controls underwent comprehensive ophthalmological examination including corneal Scheimpflug tomography with a Pentacam HR device (Oculus Optikgeräte GmbH, Wetzlar, Germany) to analyse and compare topometric, tomographic, pachymetric and Belin-Ambrósio Enhanced Ectasia Display III (BAD-D) data of both eyes of each patient.

RESULTS

Most OI patients had type I disease (n = 24; 65%) but type III-VII patients were also included. Two patients had clinically overt bilateral keratoconus. OI patients had significantly higher maximum keratometry (45.2 ± 2.1 vs. 43.7 ± 1.2; p = 0.0416), front and back elevation (3.0 ± 3.3 vs. 2.1 ± 1.3, p = 0.0201; 11.1 ± 8.2 vs. 5.0 ± 3.7, p < 0.0001), index of surface variance (25.5 ± 13 vs. 17.4 ± 8.3; p = 0.0016), index of vertical asymmetry (0.21 ± 0.14 vs. 0.15 ± 0.06; p = 0.0215), index of height asymmetry (9.2 ± 14 vs. 6.0 ± 4.5; p = 0.0421), index of height decentration (0.02 ± 0.01 vs. 0.01 ± 0.01; p < 0.0001) and average pachymetric progression (1.01 ± 0.19 vs. 0.88 ± 0.14; p < 0.0001) readings. Thinnest corneal thickness and maximum Ambrósio relational thickness were significantly lower (477 ± 52 vs. 543 ± 26; 387 ± 95 vs. 509 ± 49; p < 0.0001). Two-thirds of OI patients had corneas with a minimum thickness < 500 µm. BAD-D value was significantly higher in OI patients (2.1 ± 1.4 vs. 0.9 ± 0.2; p < 0.0001).

CONCLUSION

OI patients showed significant changes in corneal profiles compared with healthy subjects. A high proportion of patients had tomographically suspect corneas when using keratoconus diagnostic indices. Further studies are warranted to assess the true risk of corneal ectasia in OI patients.

Macular neovascularisation in a patient with osteogenesis imperfecta exhibiting a novelCOL1A1mutation

Osteogenesis imperfecta is a congenital disease that presents with varying degrees of connective tissue symptoms, including susceptibility to fracture, growth disorders and hearing loss. Here, we discuss a case in which macular neovascularisation (MNV) resulted in metamorphopsia and decreased visual acuity in a patient with osteogenesis imperfecta exhibiting a novelCOL1A1gene mutation (p.Tyr165*). The patient was a woman in her 30s who reported experiencing distorted vision and diminished visual acuity in her right eye for 1 month as well as a history of hearing loss. Rapid improvements in exudative changes and suppression of relapse were achieved after only two intravitreal injections of ranibizumab. Furthermore, since MNV occurred slightly inferior to the fovea centralis, improvements in visual acuity were better than previously reported. As fragility of Bruch’s membrane represents the basis of onset, recurrence and relapse are likely in patients exhibiting MNV, highlighting the need for regular follow-up.

Ocular characteristics and complications in patients with osteogenesis imperfecta: a systematic review

PURPOSE

Osteogenesis imperfecta (OI) is a rare inherited heterogeneous connective tissue disorder characterized by bone fragility, low bone mineral density, skeletal deformity and blue sclera. The dominantly inherited forms of OI are predominantly caused by mutations in either the COL1A1 or COL1A2 gene. Collagen type I is one of the major structural proteins of the eyes and therefore is the eye theoretically prone to alterations in OI. The aim of this systematic review was to provide an overview of the known ocular problems reported in OI.

METHODS

A literature search (in PubMed, Embase and Scopus), which included articles from inception to August 2020, was performed in accordance with the PRISMA guidelines.

RESULTS

The results of this current review show that almost every component of the eye could be affected in OI. Decreased thickness of the cornea and sclera is an important factor causing eye problems in patients with OI such as blue sclera. Findings that stand out are ruptures, lacerations and other eye problems that occur after minor trauma, as well as complications from standard surgical procedures.

DISCUSSION

Alterations in collagen type I affect multiple structural components of the eye. It is recommended that OI patients wear protective glasses against accidental eye trauma. Furthermore, when surgery is required, it should be approached with caution. The prevalence of eye problems in different types of OI is still unknown. Additional research is required to obtain a better understanding of the ocular defects that may occur in OI patients and the underlying pathology.

Clinical manifestations of osteogenesis imperfecta in adulthood: An integrative review of quantitative studies and case reports

Osteogenesis imperfecta (OI) is a rare genetic disorder of the bones caused by a mutation in Type I collagen genes. As adults with OI are aging, medical concerns secondary to OI may arise. This integrative review sought to review, appraise, and synthesize the clinical manifestations faced by adults with OI. Four electronic bibliographic databases were searched. Published quantitative, qualitative, and mixed-methods studies, as well as case reports from 2000 to March 2019, addressing a clinical manifestation in adulthood, were reviewed. Eligible studies and case reports were subsequently appraised using the Mixed Methods Appraisal Tool and Case Report Checklist, respectively. Twenty quantitative studies and 88 case reports were included for review regardless of the varying methodological quality score. These studies collectively included 2,510 adults with different OI types. Several clinical manifestations were studied, and included: hearing loss, cardiac diseases, pregnancy complications, cerebrovascular manifestations, musculoskeletal manifestations, respiratory manifestations, vision impairment, and other clinical manifestations. Increased awareness may optimize prevention, treatment, and follow-up. Opportunities to enhance the methodological quality of research including better design and methodology, multisite collaborations, and larger and diverse sampling will optimize the generalizability and transferability of findings.