Giant Cell Arteritis, Anterior Ischemic Optic Neuropathy, Optic Neuropathy, Ischemic
Conditions
Brief summary
The Sonographic Assessment of the Optic Nerve Sheath in Giant Cell Arteritis (SONIC-GCA) study will evaluate the performance of the optic nerve sheath diameter (ONSD), measured via ultrasound, to diagnose and monitor GCA. SONIC-GCA builds upon our previous pilot studies and will answer the following questions: 1. What is the performance of ONSD to identify patients with new-onset, active GCA? 2. Is ONSD useful for monitoring GCA relapses during follow-up? 3. What is the intra- and interobserver reliability of ONSD measurements? 4. Does ONSD differ between patients with and without GCA-related retinal findings?
Detailed description
SONIC-GCA is a prospective cohort and validation study conducted in centers of the Canadian Vasculitis Research Network (CanVasc).
Interventions
DIAGNOSTIC_TESTOptic nerve sheath ultrasound
The patients are examined in a supine relaxed position. The probe is gently placed on the closed eyelid with a standard ultrasound gel and adjusted to a suitable angle to display the optic nerve entry into the eyeball. Measurements are done 3mm distal to the posterior aspect of the ocular globe. Ultrasosonographic 14L5 probe is used with a safe thermal index, mechanical index and intensity limit. All patients will also undergo a bedside fundoscopic examination. Official ophthalmology consultation will be requested in patients with visual symptoms or abnormal fundoscopy.
DIAGNOSTIC_TESTStandardized GCA assessment
Clinical assesment, blood test review, temporal/axillary artery ultrasound
Sponsors
McGill University Health Centre/Research Institute of the McGill University Health Centre
Ciusss de L'Est de l'Île de Montréal
Estrie University Integrated Health and Social Services Center - University Hospital of Sherbrooke
Mount Sinai Hospital, Canada
St. Joseph's Health Care London
Ottawa Hospital Research Institute
Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
50 Years to 99 Years
Healthy volunteers
No
Inclusion 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.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Diagnostic performance of ONSD to identify new-onset GCA | Baseline | The primary outcome of SONIC-GCA is to determine the optimal ONSD cutoff for identifying GCA at the baseline visit and to assess its diagnostic performance, including sensitivity, specificity, positive and negative predictive values, and accuracy. |
| ONSD in patients with and without GCA | Baseline | At baseline, ONSD measurements (in mm) of the left and right eyes of each participant will be recorded and used to calculate the mean ONSD for patients with and without GCA. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Evaluation of the performance of ONSD to detect a GCA relapse | Up to 2 years | We will assess the diagnostic performance of the initial ONSD cutoff (from the primary objective) at each follow-up visit to differentiate between relapse and remission. This analysis will determine whether the established cutoff remains a reliable marker for monitoring disease status in GCA over time. |
| The associations between ONSD changes and GCA relapses | Up to 2 years | The association between ONSD changes and GCA relapses will be assessed during the follow-up period, in patients with GCA. |
| ONSD changes over time | Up to 2 years | The main secondary outcome will determine whether ONSD dynamically correlates with relapse risk over the follow-up period in patients with GCA, providing insight into its potential as a biomarker for disease monitoring. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Association between ONSD and Retinal Changes | Up to 2 years | The association between ONSD and the presence/absence of GCA-related retinal findings on digital fundoscopy in patients with GCA. |
| Intra- and Inter- observer reliability | Baseline | Intra- and interobserver reliability of ONSD measurements |
Countries
Canada
Contacts
Primary ContactJean-Paul Makhzoum, MD
Outcome results
None listed