Assessment of Optic Nerve Radiation in Patients With Glaucoma and Ocular Hypertension by 7 Tesla Diffusion Tensor Imaging

Sponsor

Medical University of Vienna (Other)

Overall Status

Terminated

CT.gov ID

NCT01864317

Collaborator

(none)

120

Enrollment

Location

Arms

Duration (Days)

121.8

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Glaucoma is among the leading causes for blindness in the western world. Elevated intraocular pressure (IOP) has been identified as the most important risk factor. However, some patients progress despite adequate IOP lowering while some subjects with elevated IOP never develop glaucoma. Other patients develop glaucoma although IOP measurements were always in the normal range. Therefore, other factors must be involved. In the last years, studies using MRI have been performed and evidence has accumulated that also changes in retrobulbar structures are present, in particular in the lateral geniculate nucleus and the visual cortex. However, these studies were limited by the low spatial resolution of the MRI instruments used.

The investigators propose to overcome this problem by using an ultrahigh-field Magnetom 7T whole-body MR scanner (Siemens Medical, Germany) installed at the MR Centre of Excellence at the Medical University of Vienna. This scanner is equipped with a 32-channel head coil and the SC72 high-performance gradient system and is thus perfectly suited for structural and functional imaging. The aim of the present study is to investigate whether structural and functional parameters are altered in patients with primary open angle glaucoma (POAG), normal tension glaucoma (NTG), ocular hypertension (OHT) compared to healthy control subjects. The exact topographical survey of intracranial structures such as the LGN and the assessment of neuronal structures by DTI may allow for the better assessment of therapeutic responses to new neuroprotective agents.

Condition or Disease	Intervention/Treatment	Phase
Primary Open Angle Glaucoma Ocular Hypertension Normal Tension Glaucoma	Device: 7-Tesla MRI Other: Optical Coherence Tomography Other: Heidelberg Retina Tomography Other: Scanning Laser Polarimetry Other: Humphrey Perimetry Other: Applanation Tonometry	Phase 2

Study Design

Study Type:

Interventional

Anticipated Enrollment :

120 participants

Allocation:

Non-Randomized

Intervention Model:

Parallel Assignment

Masking:

Single (Outcomes Assessor)

Primary Purpose:

Basic Science

Official Title:

Assessment of Optic Nerve Radiation in Patients With Glaucoma and Ocular Hypertension by 7 Tesla Diffusion Tensor Imaging

Study Start Date :

Nov 1, 2015

Actual Primary Completion Date :

Dec 1, 2015

Actual Study Completion Date :

Dec 1, 2015

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Primary Open Angle Glaucoma 30 patients with primary open angle glaucoma	Device: 7-Tesla MRI High resolution functional and structural imaging of the visual pathway Other: Optical Coherence Tomography Measurement of retinal nerve fiber thickness Other: Heidelberg Retina Tomography Measurement of retinal nerve fiber thickness Other: Scanning Laser Polarimetry Measurement of retinal nerve fiber thickness Other: Humphrey Perimetry Visual Field Testing Other: Applanation Tonometry Measurement of Intraocular Pressure
Experimental: Normal Tension Glaucoma 30 patients with normal tension glaucoma	Device: 7-Tesla MRI High resolution functional and structural imaging of the visual pathway Other: Optical Coherence Tomography Measurement of retinal nerve fiber thickness Other: Heidelberg Retina Tomography Measurement of retinal nerve fiber thickness Other: Scanning Laser Polarimetry Measurement of retinal nerve fiber thickness Other: Humphrey Perimetry Visual Field Testing Other: Applanation Tonometry Measurement of Intraocular Pressure
Experimental: Ocular Hypertension 30 patients with ocular hypertension	Device: 7-Tesla MRI High resolution functional and structural imaging of the visual pathway Other: Optical Coherence Tomography Measurement of retinal nerve fiber thickness Other: Heidelberg Retina Tomography Measurement of retinal nerve fiber thickness Other: Scanning Laser Polarimetry Measurement of retinal nerve fiber thickness Other: Humphrey Perimetry Visual Field Testing Other: Applanation Tonometry Measurement of Intraocular Pressure
Other: Healthy subjects 30 healthy control subjects	Device: 7-Tesla MRI High resolution functional and structural imaging of the visual pathway Other: Optical Coherence Tomography Measurement of retinal nerve fiber thickness Other: Heidelberg Retina Tomography Measurement of retinal nerve fiber thickness Other: Scanning Laser Polarimetry Measurement of retinal nerve fiber thickness Other: Humphrey Perimetry Visual Field Testing Other: Applanation Tonometry Measurement of Intraocular Pressure

Outcome Measures

Primary Outcome Measures

High resolution functional and structural imaging of the visual pathway [once on the study day (approximately 1 hour)]
The visual pathway will be imaged with 7-Tesla MRI. The images will be compared between the study groups.

Secondary Outcome Measures

Retinal nerve fiber thickness [once on the study day (approximately 10 minutes)]
Parameters obtained from GDX and OCT measurements will be compared between groups.
Visual field test [once on the study day (approximately 20 minutes)]
Parameters from the Humphrey visual field test will be used for classification of severity of glaucoma or to prove that subjects are healthy.
Intraocular Pressure [once on the study day (1 minute)]
Goldmann applanation tonometry will be used for measurement of intraocular pressure.

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

Healthy controls

Men and women aged over 18 years
Normal findings in the medical history unless the investigator considers an abnormality to be clinically irrelevant
Normal ophthalmic findings

Patients with ocular hypertension

Men and women aged over 18 years
Normal findings in the medical history unless the investigator considers an abnormality to be clinically irrelevant
Normal ophthalmic findings except presence of ocular hypertension (defined as untreated IOP ≥ 21 mmHg on at least three measurements in the medical history, no signs of glaucomatous damage in the optic disc or the glaucoma hemifield test)

Patients with primary open angle glaucoma

Men and women aged over 18 years
Normal findings in the medical history unless the investigator considers an abnormality to be clinically irrelevant
Diagnosis of manifest primary open angle glaucoma (defined as pathological optic disc appearance, glaucoma hemifield test outside normal limits and untreated IOP > 20 mmHg on at least three measurements in the medical history)
Mean Deviation in the visual field test ≥ 10dB

Patients with normal-tension glaucoma

Men and women aged over 18 years
Normal findings in the medical history unless the investigator considers an abnormality to be clinically irrelevant
Diagnosis of normal-tension glaucoma (defined as pathological optic disc appearance, glaucoma hemifield test outside normal limits and untreated IOP ≤ 20 mmHg on at least three measurements in the medical history)
Mean Deviation in the visual field test ≥ 10dB

Exclusion Criteria:

Symptoms of a clinically relevant illness in the 3 weeks before the first study day
Presence or history of a severe medical condition as judged by the clinical investigator
Abuse of alcoholic beverages, participation in a clinical trial in the 3 weeks preceding the study
Exfoliation glaucoma, pigmentary glaucoma, history of acute angle closure
Intraocular surgery within the last 6 months
Ocular inflammation or infection within the last 3 months
Pregnancy, planned pregnancy or lactating
Any metallic, electric, electronic or magnetic device or object not removable except dental fillings
Claustrophobia