Orbital Vascular Inflammation in Ischemic Optic Neuropathy and Giant Cell Arteritis

NCT07206238 | Recruiting

• 1 other identifier: H-25043110
• Study Type: observational
• Target: 122
• Locations: 1 country
• Sites: 1

Brief Summary

Giant cell arteritis (GCA) is an inflammation of the blood vessels. A dangerous complication is sudden vision loss due to insufficient blood supply to the optic nerve. However, it is often difficult to distinguish acute vision loss due to GCA from a similar condition of insufficient blood supply to the optic nerve, called NAION. Quick treatment with anti-inflammatory medication is needed in case of GCA to prevent vision loss on the eye and other serious complications. Patients with NAION have no benefit of the medication, but can have serious side effects, why it is very important to differentiate between these conditions. In this project, the investigators will use FDG PET/MRI with Black Blood (BB) sequences and OCT-imaging to study patients with GCA and/or ischemic optic nerve disease. The investigators will look for signs of inflammation in and around the small vessels of the orbit using PET/MRI and study subtle retinal changes using OCT images. The investigators want to answer the following research questions: Do patients with ischemic optic nerve disease and GCA show signs of inflammation in the orbital vessel wall on PET/MRI-scans, that are not present in patients with NAION? Do GCA patients without vision loss, but with signs of orbital vessel wall inflammation on PET/MRI-scans, have a higher risk of later vision loss than GCA patients without? Can subtle changes in the retina, detectable through OCT, help distinguish between GCA-related vision loss and NAION? This will, to our knowledge, be the first study to systematically use FDG PET/MRI BB-scans to illuminate vascular changes in the orbit of patients with GCA and/or ischemic optic nerve disease. The results may improve diagnosis and treatment of GCA and NAION in the future. The investigators hope that this will help prevent blindness and other serious complications in patients with GCA, while also avoiding unnecessary treatments for patients with NAION.

Conditions

Giant Cell Arteritis (GCA); Ischemic Optic Neuropathy; NAION - Non-Arteritic Ischemic Optic Neuropathy

Keywords

FDG PET/MRI BB; OCT; Retinal biomarkers; Giant cell arteritis; ischemic optic neuropathy

Outcome Measures

Primary Outcomes (3)

• Orbital vascular inflammation on PET/MRI

  To investigate whether there is increased FDG uptake, increased endothelial permeability, and thickening of the vessel wall in the direct vascular supply to the eye and optic nerve, as signs of orbital vascular inflammation, among patients with ischemic optic neuropathy.

  2 years

• Risk of vision loss in GCA

  To investigate whether GCA patients without visual symptoms, but with signs of orbital vascular inflammation, have a higher incidence of GCA-related eye disease after 6 months compared to GCA patients without signs of orbital vascular inflammation (and possibly again after 2 years).

  2 years

• Retinal biomarkers in AION

  To characterize the occurrence of subtle retinal changes, with a focus on paracentral acute middle maculopathy (PAMM; band-like hyperreflective changes in the middle retinal layers) and intra- and subretinal fluid (IRF/SRF; fluid in or beneath the retina) among patients with ischemic optic neuropathy.

  2 years

Secondary Outcomes (6)

• Correlation with final clinical diagnosis

  2 years

• Occurence of orbital vascular inflammation in GCA without vision loss

  2 years

• Eye examination biomarkers of orbital vascular inflammation

  2 years

• Vascular inflammation outside of the orbit

  2 years

• Orbital pathophysiologic changes in NAION

  2 years

Other Outcomes (1)

• Pathophysiology behind different retinal biomarkers in AION

  2 years

Study Arms (2)

Anterior ischemic optic neuropathy (AION)

Adults aged 50 years or more with new onset AION, here defined as ipsilateral papilledema, visual impairment (affecting BCVA and/or visual field) and relative afferent pupillary defect (RAPD).

Diagnostic Test: Positron Emission Tomography / Magnetic Resonance Imaging

Giant cell arteritis (GCA) without GCA-related vision loss

Adults aged 50 years or more, newly diagnosed with GCA (clinically and ultrasound-confirmed), and without permanent or transient loss of vision or double vision.

Diagnostic Test: Positron Emission Tomography / Magnetic Resonance Imaging

Interventions

Positron Emission Tomography / Magnetic Resonance Imaging DIAGNOSTIC_TEST

FDG PET/MRI with Black Blood sequences of the head and neck area.

Also known as: Optical Coherence Tomography, Temporal Artery Ultrasound

Anterior ischemic optic neuropathy (AION); Giant cell arteritis (GCA) without GCA-related vision loss

Eligibility Criteria

• Age: 50 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients seen at the Ophthalmological and/or Rheumatological Department at Rigshospitalet, Copenhagen, Denmark

You may qualify if:

• For AION group:
• Clinical suspicion of newly onset ischemic optic neuropathy (A-AION or NA-AION), defined by ipsilateral findings of: Papilledema; Relevant visual impairment measured by visual acuity and/or visual field; Relative afferent pupillary defect (RAPD), except if mydriatic agents have been administered or if bilateral optic neuropathy is present.
• Age ≥ 50 years
• For GCA group:
• Clinically- and ultrasound-confirmed, newly diagnosed GCA
• Absence of visual changes related to GCA in one or both eyes, including: Transient vision loss; permanent vision loss; transient double vision; permanent double vision
• Age ≥ 50 years

You may not qualify if:

• Ferromagnetic implants
• Severe renal impairment with eGFR \< 30 mL/min/1.73m²
• Allergy to MRI contrast agents
• Severe claustrophobia
• Pregnancy or breastfeeding
• Previously documented ipsilateral optic neuropathy or giant cell arteritis

Sponsors & Collaborators

• Rigshospitalet, Denmark: lead

Study Sites (1)

Rigshospitalet - Glostrup

Glostrup Municipality, 2600, Denmark

RECRUITING

MeSH Terms

Conditions

Giant Cell Arteritis; Optic Neuropathy, Ischemic

Interventions

Positron-Emission Tomography; Magnetic Resonance Imaging; Tomography, Optical Coherence

Condition Hierarchy (Ancestors)

Vasculitis, Central Nervous System; Autoimmune Diseases of the Nervous System; Nervous System Diseases; Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Arteritis; Vasculitis; Skin Diseases, Vascular; Skin Diseases; Skin and Connective Tissue Diseases; Autoimmune Diseases; Immune System Diseases; Optic Nerve Diseases; Cranial Nerve Diseases; Eye Diseases

Intervention Hierarchy (Ancestors)

Tomography, Emission-Computed; Image Interpretation, Computer-Assisted; Diagnostic Imaging; Diagnostic Techniques and Procedures; Diagnosis; Image Enhancement; Photography; Radionuclide Imaging; Tomography; Diagnostic Techniques, Radioisotope; Tomography, Optical; Optical Imaging; Investigative Techniques

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Clinical Professor

Study Record Dates

• First Submitted: September 25, 2025
• First Posted: October 3, 2025
• Study Start: January 14, 2026
• Primary Completion (Estimated): December 31, 2028
• Study Completion (Estimated): March 30, 2029
• Last Updated: May 7, 2026

Record last verified: 2026-05

Locations

DK (1)