125
was not possible in 86% of eyes and progressive dis-
ciform evolution was observed. In a series of 108 eyes
with RAP, Bottoni et al.
(33)
achieved full obliteration of
chorioretinal anastomosis in 57.1% of cases classed as
stage 1, according to Yannuzzi.
Clinical experience shows that some extrafoveal stage
1 lesions (Yannuzzi classification) are amenable to
laser photocoagulation
(34)
. However, the risk of com-
plications needs to be evaluated
(11)
and careful follow-
up is mandatory, given the high rates of persistence
and recurrence.
Surgical ablation
– Borrillo et al.
(35)
performed vit-
rectomy with detachment of the posterior hyaloid
face, surgical section of afferent arterioles and drain-
ing veins and membrane excision in 4 eyes with RAP
and PED – stage II – with resolution of intraretinal
oedema, collapse of the PED after 7-10 days and
increased average visual acuity (20/200 pre-operative
vs. 20/70).
Shimada et al.
(36)
excised the neovascular complex in 9
eyes from 8 patients – stages II and III. VA remained
stable in the post-operative period; however, signifi-
cant destruction of the RPE and the choriocapillaris
occurred in patients with serous PED. The authors
concluded that surgery may stabilise VA in stage III
but is not indicated in stage II.
Surgical section of the afferent vessel associated with
intravitreal injection of triamcinolone was performed
in one eye, with resolution of exudation and visual
acuity of 20/320 at 6 months
(37)
. Nakata M et al.
(38)
found surgical ablation (even combined with PDT)
not useful for the treatment of RAP lesions, given the
high frequency of reperfusion from retinal inflow ves-
sels associated with this procedure. Shiragami C et
al.
(39)
observed recurrence of RAP lesions in all 7 cases
treated, 2 to 13 months after surgical ablation.
Surgical ablation of RAP is no more recommended
for RAP lesions, considering the better outcomes
achieved with other treatment modalities, such as
antiangiogenic drugs.
Photodynamic therapy alone or associated with
triamcinolone acetate
. In studies of photodynamic
therapy in monkeys with neovascular complexes and
chorioretinal anastomosis, occlusion of the complex
was observed, but not of anastomoses. Anastomoses
would be responsible for neovascular complex reper-
meabilization
(40)
. Kusserow et al.
(41)
treated 6 eyes with
predominantly classic membranes and chorioretinal
anastomosis without success. No improvements in VA
were observed for any of the treated eyes. Membranes
continued to grow; no post-treatment hyperfluores-
cence was observed in FA. Stabilization or improve-
ment in visual acuity was observed after PDT in
73.3% of eyes (<3 lines loss) at 12 months, which
represent better outcomes compared to natural evolu-
tion
(14)
. However, significant VA decline was observed
in the second year, mainly due to recurrence
(15)
.
Boscia et al.
(42)
treated 13 eyes with PDT, having con-
cluded that PDT would only be useful in cases where
serous PED represents less than 50% of the lesion. In
2006, these authors referred that early treatment of
eyes with smaller lesions using PDT with verteporfin
potentially led to a beneficial effect on vision, whereas
it might worsen the natural progression of larger
lesions, with most eyes undergoing enlargement, dis-
ciform transformation or RPE tear
(43)
.
Reported short-term results of non-randomized stud-
ies on RAP lesions treated with PDT and IVTA
(44,45,46)
revealed apparently better VA outcomes and/or a
reduced number of treatment sessions compared
to PDT alone. However, recurrences were also fre-
quent
(47,48)
. Krebs I. et al.
(49)
found no significant dif-
ferences between the PDT monotherapy group and
the combined PDT and Intravitreal Triamcinolone
(IVTA) group regarding evolution of distance VA,
retinal thickness and lesion size, having concluded
that new therapeutic strategies might be required in
RAP lesions, probably including therapy with antian-
giogenic agents.
Antiangiogenic agents:
Similarly to what occurs in
classic and occult lesions, intravitreal antiangiogenic
drugs appear to lead to better outcomes in the treat-
ment of RAP lesions than PDT alone. Treatment with
ranibizumab
(50,51)
and bevacizumab
(52,53)
has shown
very promising results up to 12 months, with treated
eyes displaying significant functional and anatomical
improvements and no apparent short-term safety con-
cerns. Improved VA and short-term oedema reduc-
tion or elimination, were also observed in combined
treatments using PDT and ranibizumab
(54)
or bevaci-
zumab
(55,56)
. Information from clinical trials suggests
that the response of RAP lesions to CNV treatments
may be similar to that of other variants of neovascu-
lar AMD
(57)
. The superiority of combined treatment
with PDT and ranibizumab or bevacizumab has not
yet been demonstrated. Longer follow-up will be nec-
essary to evaluate whether the well-known tendency
for recurrence observed with PDT and entailing VA
decline is also observed with antiangiogenic drug
monotherapies or combined treatment with PDT.
Neovascular Phenotypes: RAP (Retinal angiomatous proliferation)
