Thirty-five eyes (35 patients; 14 males and 21 females) with ICNV were included in this study. The mean age was 35.94 ± 9.471 years old (range: 17-50). The duration of the first follow-up period was 24.25 ± 15.97 weeks (range: 12-83.9). The average number of injections was 2.40 ± 0.78 times (range: 1-4). Five patients (14.3%) had only 1 injection. Twelve patients (34.3%) had 2 injections and seventeen patients (48.6%) had 3 injections.
Visual outcomes and changes in OCT
Table 1 shows the changes in patients after anti-VEGF treatment. Overall, the baseline BCVA improved from 56.20 ± 14.13 letters to 73.31 ± 12.57 letters (P <0.001) at the end of the first follow-up period. The baseline CRT decreased from 353.6 ± 98.70 μm to 273.1 ± 53.56 μm (P <0.001) at the end of the first follow-up period. As shown in Table 2, there was no significant difference between the IVB and IVR groups in BCVA (P = 0.529) or CRT (P = 0.270) at the end of the first follow-up period.
Table 1. Changes in visual acuity and OCT after intravitreal anti-VEGF treatments in patients
Times
|
Eyes
|
BCVA (letters)
|
CRT(μm)
|
Baseline
|
35
|
56.20±14.13
|
353.6±98.70
|
End of the first follow-up period
|
35
|
73.31±12.57
|
273.1±53.56
|
Z
|
|
-4.481
|
-4.574
|
Pa
|
|
<0.001
|
<0.001
|
a Statistical analysis performed by the Wilcoxon Signed Ranks Test.
Table 2. Comparative Analysis of Bevacizumab and Ranibizumab groups
Agent
|
Eyes
|
Number of injections(times)
|
Baseline BCVA(letters)
|
Baseline CRT(μm)
|
BCVA at the end of the first follow-up period(letters)
|
CRT at the end of the first follow-up period (μm)
|
Bevacizumab(IVB)
|
10
|
2.50±0.85
|
53.30±16.69
|
317.5±86.41
|
75.10±11.72
|
274.6±26.95
|
Ranibizumab(IVR)
|
25
|
2.36±0.757
|
57.36±13.17
|
368.0±101.2
|
72.60±13.05
|
272.4±61.56
|
P(IVB vs IVR)
|
|
0.438b
|
0.451a
|
0.141b
|
0.529b
|
0.270b
|
a Statistical analysis performed by the sample t-test.
b Statistical analysis performed by the Mann–Whitney U test.
Comparison between subgroups according to the morphological change
Patients were classified into two groups on the basis of the morphological improvement according to OCT reports at the end of the first follow-up period: patients with morphological improvement (Fig. 1) and patients without morphological improvement (Fig. 2). As shown in Table 3, there was no significant difference in age, gender, eyes, duration of disease, number of injections, and baseline CRT between the two groups (P >0.05). Intravitreal bevacizumab and ranibizumab had similar effects on morphological changes, which indicated that the same effects on ICNV lesion subsided (P = 0.709). The baseline BCVA (63.00 ± 14.24) of patients with morphological improvement was significantly better than that of patients without morphological changes (52.18 ± 12.73; P = 0.026). After intravitreal anti-VEGF treatment, BCVA and CRT improvement were observed in both groups compared with baseline, but the differences were not statistically significant (P > 0.05).
Table 3. Comparison of parameters between patients with and without morphological improvement
Characteristics
|
Patients with morphological improvement(n=13)
|
Patients without morphological improvement(n=22)
|
P
|
Age(years)
|
34.46±9.404
|
36.82±9.620
|
0.544a
|
Gender(male/female)
|
7/6
|
7/15
|
0.288b
|
Eye(right/left)
|
3/10
|
10/12
|
0.282b
|
Anti-VEGF(bevacizumab/ranibizumab)
|
3/10
|
7/15
|
0.709b
|
Duration of disease(weeks)
|
21.53±11.85
|
25.86±18.04
|
0.775c
|
Number of injections(times)
|
2.23±0.725
|
2.50±0.802
|
0.335c
|
Baseline BCVA(letters)
|
63.00±14.24
|
52.18±12.73
|
0.026a*
|
Baseline CRT(μm)
|
347.9±104.1
|
357.0±97.73
|
0.649c
|
BCVA improvement(letters)
|
14.69±13.51
|
18.55±19.35
|
0.257c
|
CRT decrease(μm)
|
99.77±89.55
|
69.18±80.89
|
0.287c
|
a Statistical analysis performed by the sample t-test.
b Statistical analysis performed by the Chi-square test.
c Statistical analysis performed by the Mann–Whitney U test.
Univariate logistic analysis of morphological improvement
The number of injections, baseline BCVA, age, baseline CRT, and duration of disease were included in a univariate analysis using morphological improvement as the dependent variable after the last injection in the first follow-up period. Factors affecting the efficacy of intravitreal anti-VEGF injections were analysed. Univariate analysis showed that the baseline BCVA had the strongest correlation with the morphological alterations after treatments (OR=1.063, P=0.036) (Table 4).
Table 4. Univariate analysis of morphological improvement
Characteristics
|
OR
|
95%CI
|
P
|
Number of injections(times)
|
0.629
|
0.253-1.566
|
0.319
|
Baseline BCVA(letters)
|
1.063
|
1.004-1.126
|
0.036*
|
Age(years)
|
0.973
|
0.904-1.048
|
0.473
|
Baseline CRT(μm)
|
0.999
|
0.992-1.006
|
0.788
|
Duration of disease(weeks)
|
0.980
|
0.931-1.032
|
0.444
|
Comparison between subgroups according to baseline BCVA
Patients were divided into 2 groups on the basis of baseline BCVA: less than 60 letters (21 eyes) and better than 60 letters (14 eyes). The CRT of the patients whose baseline BCVA levels were less than 60 letters reduced by 66.71 μm at the end of the first follow-up period. The CRT of the patients whose baseline BCVA levels were better than 60 letters reduced by 101.3 μm at the end of the first follow-up period. Although there were no significant differences in CRT reduction between the two groups (P =0.240), CRT was lower in the group with better baseline BCVA than in the group with poorer baseline BCVA (P =0.013) after intravitreal anti-VEGF therapy (Table 5).
Table 5. Comparison of parameters between patients with different baseline BCVA levels
Characteristics
|
Baseline BCVA<60 letters
|
Baseline BCVA≥60 letters
|
P
|
Baseline CRT(μm)
|
355.8±102.4
|
350.4±96.50
|
0.877a
|
CRT change(μm)
|
66.71±89.04
|
101.3±74.79
|
0.240a
|
Final CRT(μm)
|
289.1±56.04
|
249.1±40.47
|
0.013b*
|
a Statistical analysis performed by the sample t-test.
b Statistical analysis performed by the Mann–Whitney U test.
Recurrence
Patients were scheduled to visit the doctor every 12 weeks, and 8 patients failed to follow-up. The mean follow-up period was 168.0 ± 34.82 weeks (range: 111.5-259.7). The BCVA of the 27 patients at the first follow-up period (72.74 ± 13.97 letters, P < 0.001) and at final follow-up (73.59 ± 12.08 letters, P < 0.001) had significantly improved over the baseline (55.70±15.21 letters). In this study, CNV recurred in 6 patients (Fig. 3, Fig. 4), 1 of whom experienced 2 recurrences. The recurrence rate was 22.22%. Recurrence was observed at a mean of 90.83 ± 49.20 weeks (range: 33-177) after diagnosis. There was no significant difference in age, type of anti-VEGF drugs, baseline BCVA, baseline CRT, final BCVA or final CRT between the two groups (Table 6, Table 7). There was no significant correlation between ICNV recurrence and the morphological changes at the end of the first follow-up period (χ2=0.622,P>0.05; Table 7).
Table 6. Comparison between patients with and without recurrence
Characteristics
|
Patients with recurrence(n=6)
|
Patients without recurrence(n=21)
|
P
|
Age (years)
|
37.50±11.98
|
35.38±8.755
|
0.634a
|
Baseline BCVA (letters)
|
49.67±15.14
|
57.43±15.15
|
0.279a
|
Baseline CRT (μm)
|
298.8±63.87
|
349.6±93.55
|
0.195b
|
Final BCVA (letters)
|
65.33±16.68
|
75.95±9.687
|
0.065b
|
Final CRT (μm)
|
246.2±10.94
|
269.8±52.63
|
0.195b
|
Duration of follow-up (weeks)
|
168.5±53.43
|
167.9±29.37
|
0.973a
|
a Statistical analysis performed by the sample t-test.
b Statistical analysis performed by the Mann–Whitney U test.
Table 7. Comparison of anti-VEGF therapy and morphological changes between patients with and without recurrence
|
Eyes
|
Anti-VEGF therapy
|
Morphological changes
|
bevacizumab
|
ranibizumab
|
Patients with morphological improvement
|
Patients without morphological improvement
|
Eyes
|
n
|
Eyes
|
n
|
Eyes
|
n
|
Eyes
|
n
|
Patients with recurrence
|
6
|
3
|
50.0%
|
3
|
50.0%
|
1
|
16.7%
|
5
|
83.3%
|
Patients without recurrence
|
21
|
5
|
23.8%
|
16
|
76.2%
|
7
|
33.3%
|
14
|
66.6%
|
χ2
|
|
1.535
|
0.622
|
P
|
|
0.319
|
0.633
|