Characteristics of optic disc morphology in glaucoma patients with parafoveal scotoma compared to peripheral scotoma.
OBJECTIVE
We investigated the amount and location of optic nerve head (ONH) abnormal points and the retinal nerve fiber layer (RNFL) thickness with paracentral scotoma compared to peripheral scotoma.


METHODS
Totals of 35 normal tension glaucoma (NTG) patients with isolated parafoveal scotoma (PFS) within a 10° radius in one hemifield, and 35 patients with isolated peripheral nasal step (PNS) within the nasal periphery outside 10° of fixation in one hemifield were enrolled if their mean deviation was greater than -10 decibels (dB). Global and sector optic disc stereometric parameters obtained by Heidelberg retina tomography and analyzed by Moorfields regression analysis (MRA), and retinal RNFL thickness measured using Cirrus spectral domain-optical coherence tomography were compared between the two groups. The percentages of superior and inferior field defects were evaluated.


RESULTS
In PFS, superior field defects (82.9%) were found to be dominant, whereas PNS showed a predominance of inferior field defects (80.0%). The PFS group revealed smaller rim area, more glaucomatous cup shape than the PNS group (P = 0.036, 0.012, respectively). In MRA classification, the percentage outside of normal limits (ONL) was greater in the PFS group (P = 0.006). Compared to the PNS group, the PFS group exhibited more glaucomatous ONH morphology in the temporal and inferotemporal sectors in a sector analysis of optic disc parameters, and had thinner RNFLs in the inferior quadrant, and at 7 and 8 o'clock (P = 0.007, 0.003, 0.005, respectively).


CONCLUSIONS
In early NTG, paracentral scotoma may be more significant than peripheral scotoma because of narrower optic disc rim and larger cup, especially inferotemporally.
Department of Ophthalmology and Visual Science, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Kyoung In
KI
Jung
Hae-Young L
HY
Park
Chan Kee
CK
Park
D005260:Female; D006801:Humans; D057066:Low Tension Glaucoma / Q000150:complications / Q000473:pathology*; D008297:Male; D018613:Microscopy, Confocal / Q000379:methods; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology; D009898:Optic Disk / Q000473:pathology*; D009900:Optic Nerve / Q000473:pathology; D012160:Retina / Q000473:pathology; D012189:Retrospective Studies; D012607:Scotoma / Q000150:complications / Q000473:pathology*; D041623:Tomography, Optical Coherence / Q000379:methods