97th DOG Annual Meeting 1999

P577

SLO - FUNDUSPERIMETRY AND FIXATION IN PATIENTS WITH STARGARDT' S MACULAR DYSTROPHY

O. Ehrt, G. Rudolph, K.-P. Boergen

Only few details are known on the visual field defects and their progression in Stargardt's macular dystrophy. Unstable fixation interferes with standard perimetry. Aim of our study was to use fundusperimetry with the Scanning Laser Ophthalmoscope (SLO) to assess size, shape and location of central scotomas and fixation behaviour.

Patients and method: 32 eyes of 16 patients (age 8-16y, median 30y) with different stages of Stargardt's dystrophy had a complete clinical and electrophysiological evaluation and underwent manual, static SLO fundusperimetry (Rodenstock SLO 105, Software: Scotometry 2.0). Scotoma size (stimulus size III, intensities 0, 12 and 20dB) and size of the fundus lesion, which was clearly visible with the SLO were measured. Two groups were compared: with central and eccentric fixation.

Results:

min-max
median

 

 

n

duration of symp-toms
[y]



age
[y]



visual acuity

horizontal diameter [°]

scotomas (oval shape)

centr.
island

visible
lesion

fixation

0 dB

12 dB

20 dB

central

12

0,5-7
4

10-42
29

0,2-0,8
0,5

2-15
8

6-16
10

³ 12
22

1-4,6
2

3-16
11

eccentric

20

0,3-41
12

8-61
30

0,06-0,16
0,1

4-28
10

³ 10
14

³ 14
21

0-0,2
0

7-22
14



6 eyes with "central fixation" had a second area of fixation, their central island was slightly smaller than in eyes with stable central fixation. Eccentric fixation was located 0,5°- 5º superior to the border of deep scotomas (0dB) in 22 eyes.
Conclusion: Our results suggest a progression of scotomas as follows:

1) asymptomatic annular relative scotoma.
2) annular deep scotoma 0,5º-2º perifoveolar, which reduces reading performance in spite of good VA.
3) centrifugal progression of deep scotoma. 4) loss of central island with drop of VA below 0,2.

University Eye Hospital, Ludwig-Maximilians-University, Mathildenstr. 8, D-80336 Munich, Germany


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