1. Correlation between visual acuity
and inner segment/outer segment junction
and cone outer segment tips line integrity
in uveitic macular edema
M. La Cava, P. Tortorella, E. D’Ambrosio, F. De Marco, E. Santoro, L. Iannetti
“Sapienza” University of Rome
Department of Ophthalmology
Ocular Immunovirology Service

2. INTRODUCTION DME CME SRD Diffuse macular edema (DME).
Optical Coherence Tomography (OCT) findings were used to describe the three different morphologic patterns of macular edema (ME):
Diffuse macular edema (DME).
Cystoid macular edema (CME).
- Serous retinal detachment (SRD).
DME
Increased macular thickness, small low-reflective areas with spongy appearance of the retinal layers.
CME
Low-reflective intraretinal spaces, clearly defined and separated by thin, high-reflective retinal tissue.
SRD
Neuroretinal layer separation from the retinal pigment epithelium (RPE).

3. and foveal IS/OS junction and the COST line integrity
On spectral-domain Optical Coherence Tomography (SD-OCT), the outer retina has four distinct hyperreflective lines:
1. external limiting membrane (ELM).
2. inner segments and outer segments of the photoreceptors junction (IS/OS).
3. the cone outer segment tips (COST) or Intermediate Line or Verhoeff’s membrane.
4. RPE.
1. The innermost ELM is formed by the back reflection of the zonulae adherentes that join the inner segment to the Muller cells.
2. The IS/OS junction is thought to represent the boundary between the inner and outer segments of the photoreceptors and is localized between the ELM and the RPE histologically.
3. The COST line represents the outer tip of the cones.
4. The outermost RPE line separates the photoreceptors from the Bruch’s membrane and choriocapillaris.
PURPOSE
To investigate the correlation between best-corrected visual acuity (BCVA) 
and foveal IS/OS junction and the COST line integrity
in eyes with uveitic ME.

4. and clinical characteristics of the study population
METHODS
52 eyes of 33 patients.
Retrospective, observational study.
All patients underwent  SD-OCT examination with Spectralis OCT (Heidelberg Engineering, Heidelberg,
Germany).
The correlation between the BCVA and ME pattern, the integrity of the foveal
IS/OS junction and COST line was evaluated with a multivariate correlation.
The correlation between the interruption of the foveal IS/OS junction and COST line was
analyzed with a univariate logistic correlation.
Anatomic location
of uveitis (eyes)
Anterior
12 (23.07%)
Intermediate
20 (38.46%)
Posterior
7 (13.46%)
Panuveitis
13 (25%)
Classification of uveitis (patients)
Idiopathic
36 (80%)
TBC
2 (4.4%)
Behçet
VKH
JIA
5 (11.1%)
Birdshot
1 (2.2%)
B27+ AAU
Demographic
and clinical characteristics
of the study population
Median Age (Q1-Q3)
32 (9-77)
Gender
Male/Female
22/23
Median FU mos (Q1-Q3)
25.5 ( )
Median duration (Q1-Q3)
48 ( )
Laterality
Unilateral
38 (84.4%)
Bilateral
7 (15.6%)

5. RESULTS Number of patient, mean foveal thickness (CST) and median BCVA
according to the different morphological features observed.
N of eyes
(% on 52 eyes)
mean CST ± SD
median BCVA
(Q1-Q3)
DME
39 (75%)
354 ±124
0.7 (0.03 – 1.0)
CME
13 (25%)
430 ± 222
0.6 (0.06 – 1.0)
SRD
11 (21.2%)
432 ± 154
0.4 (0.03 – 1.0)
No SRD
41 (78.8%)
406 ± 216
0.7 (0.06 – 1.0)
DME + SRD
3 (5.8%)
372 ± 176
0.7 (0.1 – 1.0)
CME + SRD
8 (15.4%)
467 ± 257
0.6 (0.1 – 1.0)
COST line disruption
602 ± 303
0.2 (0.06 – 0.8)
COST line integrity
348 ± 99
0.8 (0.03 – 1.0)
IS/OS junction disruption
26 (50%)
480 ± 253
0.35 (0.06 – 1.0)
IS/OS junction integrity
342 ± 102
0.9 (0.03 – 1.0)
Negative correlation between BCVA and central retinal thickness (p<0.001), cystoid pattern of edema (p<0.05)
and COST line interruption (p<0.01).
Strong correlation between IS/OS segment and COST line integrity (p<0.05).
a. Disruption of COST line.
b. Disruption of the photoreceptor IS/OS junction.
c. Disruption of COST line and IS/OS junction together.

6. CONCLUSIONS
IS/OS segment defect and COST line interruption and central retinal thickness are correlated with poor vision.
BCVA is strongly affected by the cystoid pattern.
The COST line integrity appears to be the most important factor in the visual prognosis of uveitic ME.
FINANCIAL DISCLOSURE:
This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.