An observational study in Birdshot Chorioretinopathy and Posterior Uveitis, sponsored by Assistance Publique - Hôpitaux de Paris. Recruiting at 1 site in France. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-03-04.
Sponsored by Assistance Publique - Hôpitaux de Paris · Observational
The purpose of this study is twofold:
To analyze the clinical features of a cohort of patients with birdshot chorioretinopathy (BCR), an inflammatory bilateral ocular disease, affecting the choroid and the retina.
Various imaging techniques will be used to assess the effect of the disease on the retina and the choroid.
A standardized assessment of the visual function will be performed with visual acuity, visual field and color vision testing. The quality of life of the patients will be evaluated with the VFQ-25 questionnaire.
These analyses will help delineating different forms of the disease among its heterogeneous presentations.
Birdshot chorioretinopathy is a bilateral chronic posterior uveitis that has been named in 1980. The "birdshot lesions" are the hallmark of the disease. In their most typical aspect these lesions are ovoid shaped hypopigmented spots at the level of the choroid.
One of the main difficulties of the diagnosis lies in the spectrum of presentations of the disease. The typical birdshot lesions are ovoid with their main axis oriented toward the optic disc. However, some are round and the can be clearly seen on fundus examination while others can be limited to subtle depigmentations. Typical lesions are one-quarter to one-half disc diameters, but confluent lesions may yield larger areas of depigmentation that are difficult to recognize. Although the typical lesions are depigmented, their presentation may change over time and pigment or atrophy may replace the initial cream-colored spots. The typical location, or the most easily seen location of the spots, is nasal to the optic disc. However, involvement of the posterior pole inside the temporal arcade is also possible. The spots usually predominate in the mid-periphery, but may also extend to the equator. A standardized classification of the birdshot lesions according to their size, their number, their pigmentation and their localization has been suggested to help in the categorization of the various disease presentations and for the longitudinal follow-up of affected patients. Spots clearly visible at the time of the diagnosis may disappear later. Hence, if the diagnosis of the birdshot chorioretinopathy is not made when spots are clearly visible, later presentations may not meet the definition commonly used for the disease. The disappearance of birdshot spots after treatment has been documented, but the effect of treatment on spots has not yet been assessed in large cohorts of patients. Indocyanine green angiography has been suggested as a reliable method to detect spots. However, it remains to be validated by a randomized assessment comparing indocyanine green angiography to color photographs for the detection of birdshot lesions.
Fluorescein angiography is useful in patients with birdshot chorioretinopathy to assess disease activity. In active disease, angiographic findings include leakage of the retinal veins, macular edema and optic disk hyperfluorescence. These findings are not disease specific, but they require a careful examination of the fundus seeking subtle spots when birdshot lesions are not obvious.
Given the above, the first goal of our prospective cohort study is to assess the heterogeneity of the disease, its spectrum of presentation and its evolution over time.
One of the characteristics of birdshot chorioretinopathy is its association with the HLA-A29 allele, which constitutes the strongest link between a disease and class I HLA allele. The mechanism by which HLA-A29 confers a risk for birdshot chorioretinopathy is a key question that remains unanswered. As with other associations between HLA class I antigens and diseases (HLA-B27 with spondylarthropathies and HLA B51 with Behçet's disease), the physiopathogeny of these links have not been elucidated.
Other factors playing a role in the physiopathogeny of the disease and not linked to the major histocompatibility complex are researched. A few families of patients with birdshot chorioretinopathy have been reported, which could point to additional genetic factors for disease susceptibility but does not rule out an environmental effect.
Hence, the complex physiopathology of birdshot chorioretinopathy could involve the HLA-A29 allele, other unknown genetic factors, as well as environmental factors.
Given the above, we are planning a GWAS (Genome Wide association Study) based on DNA of the cohort patients, which will be performed with the aim to identify other susceptibility genes associated with BCR.
61 studies on the registry are indexed under Uveitis, Posterior; 4 are open to participants now.
This study's planned enrollment of 600 is above the median of 42 across 10 observational studies indexed under Uveitis, Posterior.
Browse Uveitis, Posterior studies →Assistance Publique - Hôpitaux de Paris is the lead sponsor of 3,592 studies on the registry; 1,033 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Patients followed in the Department of Ophthalmology in a Paris University Hospital. Tertiary center for rare inflammatory ocular disorders.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
1. HLA-A29 positivity 2. Retinal vasculitis 3. Cystoid macular edema
Exclusion Criteria:
Patients with a diagnosis of birdshot chorioretinopathy, with confirmed HLA-A29 positivity.
Other: Observational study
The goal of the study is purely observational. Treatment decisions will be made by physicians according to the grading of the intraocular inflammation related to birdshot chorioretinopathy and to their consequences on visual function. These treatment decisions will be independent from the observational study.
Best Corrected Visual Acuity (BCVA)
Standard decimal clarity for distance visual acuity. It is expressed from 0 which is minimum \& worse value, corresponding to no light perception; to 1.0 (20/20) which is maximum \& best value
Time frame: Through study completion, an average of 1 year
Visual field testing
Humphrey 30-2 automated threshold perimetry with foveal sensitivity. It is expressed in Mean Deviation from -25 decibels or unachievable which is minimum \& worse value, to 0 decibel, which is maximum \& best value.
Time frame: Through study completion, an average of 1 year
Color vision
Assessed with Desaturated Lanthony 15-Hue Test: an objective technic evaluating sensitivity to color \& colour vision deficiency. Test result is categorized as Abnormal for minimum \& worse evaluation; and Normal for maximum \& best evaluation.
Time frame: Through study completion, an average of 1 year
National Eye Institute 25-Item Visual Function Questionnaire
Using a scale from 0 for minimum \& worse, to 100 for maximum \& best result; this questionnaire measures influence of visual impairment on various dimensions of quality of life such as emotional well-being and social functioning
Time frame: Through study completion, an average of 1 year
Assessment of birdshot spot size
It describes appearance of the birdshot spots as small for minimum or large for maximum.
Time frame: Through study completion, an average of 1 year
Assessment of birdshot spot number
Spots are counted and categorized as \<10 for minimum value \& \>50 for maximum
Time frame: Through study completion, an average of 1 year
Assessment of birdshot spot localization
Spots are categorized as Juxtapapillary, Equator \& Diffuse.
Time frame: Through study completion, an average of 1 year
Assessment of birdshot spot pigmentation
Spot pigmentation is analysed and categorized as No pigmentation for minimum \& Sever for maximum.
Time frame: Through study completion, an average of 1 year
Assessment of edema
Papillary \& macular edema are analysed by Optical Coherence Tomography, using a scale from 0 to 4 respectively for minimum \& best, to maximum \& worse value.
Time frame: Through study completion, an average of 1 year
Assessment of retinal vasculitis
Arterial \& venous vasculitis are analysed by Fluorescein Angiography, using a scale from 0 to 4 respectively for minimum \& best, to maximum \& worse value.
Time frame: Through study completion, an average of 1 year
Plan to share: Yes — Sharing of anonymized clinical data with other investigators experienced in the care of patients with birdshot chorioretinopathy.
Started Nov 2004 (actual). Primary completion is estimated for Dec 2030, 313 months after the start.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Assistance Publique - Hôpitaux de Paris →