Macular vessel density in untreated normal tension glaucoma with a hemifield defect
Nozomu Uchida1,2, Kyoko Ishida3, Ayako Anraku2
1Department of Ophthalmology, Toho University Graduate School of Medicine, Tokyo, Japan.
Japanese Journal of Ophthalmology
|October 19, 2019
Summary
In normal tension glaucoma (NTG) with hemifield defects, both normal and affected visual fields show reduced macular vessel density (MVD) and structural damage. These early changes suggest potential hemodynamic deficiencies even before vision loss is apparent.
Area of Science:
- Ophthalmology
- Glaucoma Research
- Optical Coherence Tomography Imaging
Background:
- Normal tension glaucoma (NTG) is characterized by optic nerve damage and visual field loss without elevated intraocular pressure.
- Early detection of structural and hemodynamic changes in NTG is crucial for timely intervention.
- Hemifield defects (HFD) in NTG indicate progressive optic neuropathy.
Purpose of the Study:
- To investigate macular vessel density (MVD) and structural alterations in untreated NTG with HFD.
- To compare MVD and structural findings in NTG eyes with those in healthy eyes.
- To assess changes in perimetrically normal hemifields of NTG eyes.
Main Methods:
- A case series comparing 34 untreated NTG eyes with HFD to 28 healthy eyes.
- Optical Coherence Tomography Angiography (OCT-A) and Spectral Domain OCT (SD-OCT) were used for MVD and inner macular thickness (IMT) measurements.
- Retinal nerve fiber layer (cpRNFL) and macular ganglion cell complex (mGCC) thicknesses were measured.
Main Results:
- NTG eyes with HFD showed reduced MVD, cpRNFL, and mGCC thicknesses in normal hemifields compared to healthy eyes.
- Defective hemifields in NTG eyes exhibited reduced IMT, cpRNFL, and mGCC thicknesses compared to their own normal hemifields.
- MVD did not differ between the defective and normal hemifields within NTG eyes.
Conclusions:
- Hemodynamic deficiencies and structural damage may be present in the perimetrically normal hemifields of NTG eyes.
- Further research is needed to determine if reduced MVD precedes structural changes or varies with disease severity.
- These findings suggest early vascular and structural alterations in NTG, even in areas without apparent visual field loss.
Keywords:
Hemifield defectMacular vessel densityNormal tension glaucomaOptical coherence tomography angiographyMore Related Videos
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