Giant Cell Arteritis, Temporal Arteritis, Optic Nerve Diseases, Diagnosis
Conditions
Brief summary
Giant cell arteritis (GCA) is an inflammatory disease of large and medium arteries that can cause irreversible vision loss. Glucocorticoids (GCs) rapidly suppress inflammation, but diagnostic imaging tests such as temporal artery ultrasound or biopsy often become falsely negative within days of treatment. The optic nerve sheath diameter (ONSD), measurable by ocular ultrasound, reflects perineural edema and may serve as a quantitative biomarker of ocular inflammation in GCA. The SONIC-TIME study (Early Temporal Dynamics of Optic Nerve Sheath Diameter After Glucocorticoid Therapy in Giant Cell Arteritis) is a single-center, prospective observational substudy embedded within SONIC-GCA (NCT05749094) at Hôpital du Sacré-Cœur de Montréal. It aims to characterize how rapidly ONSD decreases after GC initiation and how this trajectory relates to cumulative GC exposure, intravenous methylprednisolone, and early use of steroid-sparing therapies. Sixty participants with newly diagnosed GCA will undergo serial optic nerve sheath ultrasound, blood tests (CRP, ESR), and when feasible, temporal artery ultrasound over the first two months of therapy (Days 3, 7, 10, 14, 21, 28, and Month 2). No experimental treatments are given; all participants receive standard-of-care therapy. The primary objective is to quantify the percent change in mean ONSD from baseline to Day 28. Secondary objectives include modeling ONSD change over time, assessing associations with cumulative steroid dose and inflammatory markers, and estimating the time to normalization below the SONIC-GCA cutoff. Findings will define the optimal imaging window and refine the diagnostic and monitoring role of optic nerve ultrasound in GCA.
Interventions
DIAGNOSTIC_TESTOptic Nerve Sheath Ultrasound
Optic nerve sheath ultrasound will be performed in combination with a digital retinal fundoscopy.
DIAGNOSTIC_TESTTemporal artery ultrasound
With measurement of the intima-media complex and calculation of the OGUS.
DIAGNOSTIC_TESTBloodwork : CRP and ESR
At each visit
Sponsors
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 No maximum
Inclusion criteria
1. Participants must be enrolled in SONIC-GCA and must have: * completed the baseline optic nerve sheath ultrasound * confirmed GCA as determined by the baseline standardized GCA assessment in SONIC-GCA. 2. Exposure to glucocorticoids for ≤ 48 hours and ≤ 160 mg prednisone-equivalent before baseline. 3. Ability and willingness to provide written informed consent. 4. Agreement to complete the SONIC-TIME intensive follow-up schedule.
Exclusion criteria
1\) Concurrent participation in a blinded interventional pharmaceutical clinical trial.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in mean ONSD (in mm) from day 0 to day 28 | Day 28 | To quantify the change in mean ONSD (in mm, by ultrasound) between baseline (Day 0) and Day 28 after GC initiation in patients with GCA exposed to ≤ 48 hours and ≤ 120 mg prednisone-equivalent before baseline. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in mean ONSD (in mm, using ultrasound) from day 0 to day 14 | Day 14 | To quantify the change in mean ONSD between baseline (Day 0) and Day14 after GC initiation in patients with GCA exposed to ≤ 48 hours and ≤ 120 mg prednisone-equivalent before baseline. |
| Change in mean ONSD (in mm, using ultrasound) from day 0 to month 2 | Month 2 | To model ONSD change over the first eight weeks using with time-updated cumulative GC exposure. |
| Association between cumulative glucocorticoids (GCs, in mg) and ONSD (in mm, by ultrasound) | Month 2 | To determine the dose-response relationship between ONSD and cumulative GC exposure. |
| Association between IV methylprednisolone (binary : yes or no) and ONSD (in mm, by ultrasound) | Month 2 | To evaluate the influence of IV methylprednisolone on ONSD evolution. |
| Association between immunosuppressive therapy (categorical, documented using medication list) and ONSD (in mm, by ultrasound) | Month 2 | To assess the impact of early initiated steroid-sparing therapies initiated as standard of care on ONSD trajectory. |
| ONSD threshold (from the SONIC-GCA trial) performance over time | Month 2 | To evaluate the time-adjusted ONSD performance based on the established SONIC-GCA ONSD cutoff. |
| Time (in days) to ONSD normalization | Month 2 | To estimate the adjusted time to first attainment of an ONSD value below the established SONIC-GCA ONSD cutoff. |
| Association between inflammatory markers and ONSD | Month 2 | To quantify correlations between ONSD and systemic inflammatory biomarkers over the early therapy period. |
| Association between OGUS and ONSD | Month 2 | To examine associations between ONSD and the temporal artery ultrasound OGUS score over the early therapy period. |
| Association between digital retinal fundoscopy and ONSD (in mm, by ultrasound) | Month 2 | To compare ONSD trajectories between participants with and without GCA-related retinal abnormalities on digital retinal fundoscopy. |
Countries
Canada
Contacts
CONTACTJean-Paul Makhzoum, MD, MSc
STUDY_CHAIRJean-Paul Makhzoum, MD, MSc
CISSS du Nord-de-l'ile de Montreal
Outcome results
None listed