Diabetes-associated retinal nerve fiber damage evaluated with scanning laser polarimetry.
OBJECTIVE
To evaluate retinal nerve fiber layer (RNFL) thickness in patients with diabetes mellitus compared with age-matched normal control subjects, to assess the correlation between the RNFL thickness and the severity of retinopathy, and to investigate whether diabetes mellitus is a potential source of abnormal results in glaucoma screening or evaluation with scanning laser polarimetry (SLP).


METHODS
Cross-sectional analysis of normal and diabetic eyes.


METHODS
setting: Institutional clinical study. patients: One hundred twenty-eight subjects with type 2 diabetes mellitus and 50 age-matched normal control subjects without glaucoma or glaucoma-suspect. All patients underwent imaging with SLP and repeatable automated perimetry. Subjects with diabetes mellitus were classified into four stages on the basis of the severity of retinopathy that was assessed by dilated funduscopic examination, high-quality fundus color photography, and fluorescein angiography.


METHODS
The SLP (GDx VCC software, version 5.5.0) parameters.


RESULTS
The RNFL thickness in patients with diabetes mellitus was reduced significantly compared with age-matched normal control eyes (P < .01). Moreover, all RNFL thickness parameters of the GDx VCC software decreased significantly as an exacerbation of diabetic retinopathy (P = .0019, P = .0045, P = .0010 for temporal-superior-nasal-inferior-temporal (TSNIT) average, superior average, inferior average, respectively). The nerve fiber indicator also increased significantly (P < .0001), despite an absence of glaucomatous optic nerve damages.


CONCLUSIONS
The RNFL thickness in type 2 diabetes mellitus, which was measured by GDx VCC software, significantly decreased with the severity of diabetic retinopathy. The presence of diabetes mellitus can be a source of false-positive results and overestimation of glaucomatous optic neuropathy when eyes are screened with GDx VCC software.
Takahashi
Hirokazu
H
Senshokai Eye Institute, Kyoto, Japan. kaz0726@abelia.ocn.ne.jp
Goto
Tomomi
T
Shoji
Takuhei
T
Tanito
Masaki
M
Park
Masami
M
Chihara
Etsuo
E
D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis*; D003930:Diabetic Retinopathy / Q000175:diagnosis*; D003941:Diagnostic Techniques, Ophthalmological; D005260:Female; D005451:Fluorescein Angiography; D005901:Glaucoma / Q000175:diagnosis; D006801:Humans; D007834:Lasers; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009898:Optic Disk / Q000473:pathology; D009901:Optic Nerve Diseases / Q000175:diagnosis; D012165:Retinal Ganglion Cells / Q000473:pathology*