Optic nerve sheath ultrasound to diagnose and monitor giant cell arteritis

The Sonographic Assessment of the Optic Nerve Sheath in Giant Cell Arteritis

This research will test whether measuring the optic nerve sheath diameter with ultrasound can help diagnose and monitor new-onset giant cell arteritis in people over 50 referred for suspected disease.

Quick facts

• Study type: Observational
• Enrollment: 285 (estimated)
• Ages: 50 Years to 99 Years
• Sex: All
• Sponsor: Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal (Academic / other)
• Locations: 6 sites (London, Ontario and 5 other locations)
• Trial ID: NCT05749094 on ClinicalTrials.gov

What this trial studies

SONIC-GCA is a prospective cohort and validation study carried out across Canadian Vasculitis Research Network centers. It uses standardized optic nerve sheath diameter (ONSD) measurements by ultrasound at baseline and during follow-up to identify active new-onset GCA and to detect relapses. The study will compare ONSD findings with clinical diagnoses and retinal findings, and will quantify intra- and interobserver reliability of the ultrasound measurements. Patients on prolonged systemic glucocorticoids, on immunosuppressive therapy, or with prior retinal or optic nerve disease are excluded to limit confounding.

Who should consider this trial

Good fit: Adults older than 50 who are newly referred for suspected giant cell arteritis, able to consent, willing to attend study visits, and not currently on prolonged glucocorticoids or other immunosuppressants are ideal candidates.

Not a fit: People referred for a suspected GCA relapse, those currently on prolonged systemic glucocorticoids or other immunosuppressive therapy, and those with prior retinal or optic nerve disease are unlikely to benefit from the test in this study.

Why it matters

Potential benefit: If successful, this could provide a quick, noninvasive bedside ultrasound measurement to help diagnose and follow giant cell arteritis and potentially reduce delayed diagnoses or the need for invasive tests.

How similar studies have performed: The investigators' prior pilot studies and limited literature suggest ONSD ultrasound can reflect optic involvement, but a large prospective validation in GCA remains novel.

Eligibility criteria

Our population of interest is patients referred from any settings for suspected, new-onset GCA.

Inclusion criteria:

To be included in SONIC-GCA, participants must meet all the following criteria:

1. Age \> 50 years.
2. Referral to a GCA clinic for suspected, new-onset GCA.
3. Ability to understand and willingness to sign an informed consent form.
4. Willingness to comply with study visits and procedures.

Exclusion criteria:

An individual who meets any of these criteria will be excluded from SONIC-GCA:

1. Referral for a suspected GCA relapse.
2. Current use of systemic glucocorticoids, with the following duration at the baseline visit: ≥ 14 consecutive days of oral glucocorticoids in the previous 30 days, or ≥ 7 consecutive days of oral glucocorticoids if intravenous glucocorticoids were administered in the previous 30 days.
3. Current use of any conventional or biologic immunosuppressive therapy.
4. Known previous medical history of retinal diseases, optic nerve diseases, demyelinating diseases, normotensive hydrocephalus, intracranial tumors (benign or malignant), or any conditions associated with intracranial hypertension.
5. Any condition that impairs the ability to perform optic nerve sheath ultrasound or fundoscopy.

Where this trial is running

London, Ontario and 5 other locations

• St-Joseph's Health Care London — London, Ontario, Canada (Not_yet_recruiting)
• Sinai Health - Toronto — Toronto, Ontario, Canada (Not_yet_recruiting)
• MUHC - McGill University — Montreal, Quebec, Canada (Not_yet_recruiting)
• Vasculitis Clinic, Hopital du Sacre-Coeur de Montreal — Montreal, Quebec, Canada (Recruiting)
• CIUSSS de l'Est-de-l'ile de Montreal — Montreal, Quebec, Canada (Not_yet_recruiting)
• CIUSSS de l'Estrie - CHUS — Sherbrooke, Quebec, Canada (Not_yet_recruiting)

Study contacts

• Study coordinator: Jean-Paul Makhzoum, MD

Conditions Giant Cell Arteritis; Anterior Ischemic Optic Neuropathy; Optic Neuropathy, Ischemic