135
diagnosis confirmation. Documentation of polyps (num-
ber, location, size) and associated features (neurosensory
detachment, serous or haemorrhagic PED, haemor-
rhage) may be assessed by OCT. Polypoidal lesion and
branching vascular network identified in ICG may be
visualized on spectral domain OCT in near 95% of the
cases as areas of moderate reflectivity between the clearly
delineated abnormal section of retinal pigment epithe-
lium and Bruch’s membrane
(30)
. Polypoidal lesions are
visualized as anterior protrusions of a highly reflective
RPE line. With “en face OCT”
(31)
branching vascular
networks were detected as elevations of the RPE. Serous
pigment epithelial detachments may be seen as round
protrusions of the RPE and are often accompanied by
adjacent smaller round protrusions of the RPE, consis-
tent with polypoidal lesions. These protrusions of the
RPE are often fused and typically appeared as a ‘snow-
man’. Subsequent longitudinal examination reveals the
polypoidal lesions to be sharp protrusions of the RPE
with moderate inner reflectivity. Consistent with the
location of the branching vascular network, a highly
reflective line may be seen often just beneath the slightly
elevated reflective line of RPE
(30,31)
.
6. Differential diagnosis
Differential diagnosis of PCV with central serous chorio-
retinopathy, AMD with CNV, inflammatory conditions
and tumors is not always easy and needs ICG for a clear
differentiation.
Polypoidal choroidal vasculopathy is a primary cause of
macular serous retinal detachment without hemorrhage
in patients over 50 years of age in Asian population
(32)
.
Since clinical and fluorescein angiographic findings are
often indistinguishable among central serous chorioreti-
nopathy, PCV, and occult choroidal neovascularization,
indocyanine green angiography might help to establish
a more definitive diagnosis
(16,33)
. Central serous chorio-
retinopathy shows staining or late leakage but not an
abnormal choroidal vascular network neither polyps.
The differential diagnosis becomes more challenging
when lipid exudation and small PED are associated.
ICG may be helpful differentiating PED from polypoi-
dal lesions. Small PED from central serous chorioreti-
nopathy become hypofluorescent in late phases ICG and
hyperfluorescent in late phases fluorescein angiography.
In contrast, polypoidal lesions are usually hyperfluores-
cent in late phases ICG because of its vascular nature
(16)
.
PCV represents a subtype of CNV in AMD
(4,10,17,18,19)
.
However some features distinguish PCV from other
subtypes of CNV: eyes with PCV are characterized by
a higher incidence of neurosensory detachments, greater
neurosensory detachment height, and less intraretinal
oedema than eyes with occult or predominantly clas-
sic CNV
(34)
. Non polypoidal lesions in exudative AMD
patients tend to produce small calibre vessels that are
associated with grayish membranes not easily observed
clinically, in contrast with the redish-orange lesions clini-
cally observed in PCV and corresponding to vascular sac-
cular polypoid lesions
(18,34,35,36)
. Stromal choroidal fibrosis
is common in predominantly classic and occult lesions
but is quite rare in PCV. PED associated with CNV in
AMD has a poor prognosis whilst PED in PCV lesions
virtually never forms fibrotic scars
(16,18,29)
. The natural
evolution of CNV in AMD eyes to fibrosis and disciform
scar is not observed in PCV eyes.
Tumoral lesions like choroidal circumscribed heman-
gioma, renal cell carcinoma or metastasis from carcinoid
syndrome may also be confused with PCV
(29)
. Again
ICG is essential for differentiation. Choroidal hemangio-
mas show, in general, a rapid filling of dye in very early
phases and a washout in late phases. ICG characteristic
lesions of PCV are not observed in choroidal or meta-
static tumors and ultrasound is also effective for charac-
terization of the tumoral mass.
Inflammatory lesions like, posterior scleritis, multifocal
choroiditis, panuveitis, acute posterior multifocal plac-
oid pigment epitheliopathy, Harada disease, sympathetic
uveitis, birdshot chorioretinopathy may also be confused
with PCV. PCV does not course with anterior or pos-
terior uveitis neither with pain or staining of the optic
disc in fluorescein angiography
(4,16,18,29)
. Lipid deposition,
often observed in PCV is not commonly seen in inflam-
matory conditions. Scleral or choroidal thickening and
liquid in the subtenon space have never been described
in PCV eyes
(18,29)
.
7. Treatment
Treatment of PCV lesions is only recommended when
central vision is being threatened by persistent and pro-
gressive exudative changes. Otherwise, a conservative
approach is recommended.
Different treatment modalities like laser photocoagula-
tion, transpupillary thermotherapy, photodynamic ther-
apy with verteporfin (PDT), and surgery or intravitreal
antiangiogenic drugs have been reported. However no
randomized, controlled studies have been performed to
Neovascular Phenotypes Polypoidal
