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14.2 Retinal Capillary Hemangioblastoma
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a
c
b
d
Fig. 14.2 Left eye (a) of a 12-year-old male, with a soli-
tary retinal angioma (blue arrow) in inferior periphery (b).
At 5years follow-up, while the right eye failed treatment
often bilateral and multiple and is seen in the retinal periphery (Figs. 14.2 and 14.3). On OCT,
these angiomas are seen as hyperreective mass
lesions in the inner retina, and as they grow, they
push the retina outwards [14]. The sessile retinal
angiomas may be seen on the optic disc or the
juxtapapillary area Figs.14.4 and 14.5). A single
unilateral RH may be seen sporadically. However,
in the presence of positive family history or any
of the systemic lesions of VHL discussed above,
the diagnosis of inherited VHL should be made.
Notably, new RH may keep appearing over time
in the young offspring. The RH may vary from
the very small detected on screening of the offspring to the large symptomatic. As the peripheral RH lesions grow, they tend to develop a
(c), the left eye remained stable (blue arrow) after laser
photocoagulation (d)
Fig. 14.3 A 24-year-old male with a family history of
VHL presented with diminution of vison in right eye due
to exudative retinal detachment. A large retinal angioma
(black arrow) was seen in upper temporal periphery, along
with a small angioma (blue arrow)
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abc
Fig. 14.4 A 29-year-old male presented with episodes of
sweating, palpitations, headache, and breathlessness on
exertion for 3 months. Detected to have paroxysmal
hypertension, he was diagnosed with pheochromocytoma.
Wide eld fundus photograph (a) of right eye showed reti-
nal angiomas (white arrows) nasal to optic disc and in
superior periphery, suggestive of VHL disease. Fluorescein
angiography showed hyperuorescent lesions nasal to
optic disc, in superior (b) and inferior (c) periphery
ab c
Fig. 14.5 A 37-year-old woman had loss of vision in left
eye for 2years, with vision 6/60. Right eye was normal
(a). Left eye (b) had a juxtapapillary retinal capillary
hemangioma (black arrow), peripapillary exudative reti-
markedly dilated and tortuous feeder arteriole
and a draining vein, a characteristic VHL feature
(Figs.14.1 and 14.3). The RH are highly permeable, and irrespective of the site, the leaking uid,
and exudates, accumulate in the macula as massive hard exudates and submacular uid
(Fig.14.3). In the advanced stages, there may be
a massive exudative retinal detachment. As the
RH grow large, they develop brous proliferation
on their surface, rmly adherent to the posterior
vitreous face. The contracting scar tissue may
pull the RH and the retina anteriorly, leading to a
tractional retinal detachment. Fundus uorescein
angiography (FFA) is a sensitive tool for the early
detection of even small angiomas, as these show
early hyperuorescence and late staining
(Fig.14.4) [14]. Ultrawide eld FFA is helpful as
most RH lesions are in the peripheral retina. It
has been found to be more sensitive than ophthal-
nal detachment (blue arrows), and retinal exudates (red
arrows). There were no apparent feeder vessels.
Fluorescein angiography showed the retinal angioma on
the optic disc (c)
moscopy and the conventional FFA [15]. Further,
on wide angle FFA, besides staining of the
hemangioblastoma, nearly 1/3rd of the patients
with larger peripheral retinal hemangioblastoma
may show extensive non-perfusion of the peripheral retina, which may be associated with retinal
neovascularization on the tumour surface [16].
The pathology of the cerebellar and retinal
hemangioblastoma is similar and consists of a
network of thin-walled capillary vessels, 8–14μm
in diameter and lined with at endothelium. The
capillary network is separated by vacuolated
foamy (phospholipids-lled) stromal cells and
collagenous bres [17]. These stromal cells show
heterozygosity for the VHL gene, but not the vascular cells and thus qualify for the label of a neoplasm. The overexpression of the VEGF is
responsible for the massive new vessels in these
tumours and increased permeability [6].
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14.2.5 Treatment ofvon HippelLindau’s Disease
Various treatment strategies have been used,
including plaque, external beam radiation, and
photodynamic therapy, with mixed results. Except
for laser photocoagulation for very small RH and
Pars plana vitreous surgery for large tumours, no
other strategy has been able to eradicate the RH
tumour masses. Small RH (<1.5 mm) with or
without exudation can be successfully treated
with laser photocoagulation [18]. Peripheral angiomas >1.5 to <4mm are more challenging to treat
with laser photocoagulation and may require multiple treatment sessions (Fig. 14.6). The peripheral large RH lesions are treated with triple
freeze-thaw cryotherapy applied either trans-conjunctival or trans-scleral after making a conjunctival incision. Cryotherapy runs the risk of
increasing brous contraction and formation of
tractional retinal detachment. Occasionally, the
retina may develop tears leading to a combined
tractional and rhegmatogenous retinal detachment. Pars plana vitreous (PPV) surgery to excise
the tumour has the highest success rate for eradicating large RH tumours [18]. The PPV is often
combined with scleral buckling. Doing laser photocoagulation preoperatively to the feeder vessels
and the tumour mass may be helpful. The posterior vitreous hyaloid membrane is rather rmly
adherent to the retina in young people, which
poses a challenge to remove. Postoperative brous
proliferation may necessitate more than one procedure [19, 20]. During vitreous surgery, a transvitreal ligation of the feeder vessel can be done
before the enblock dissection of the tumour [21].
Although the fundamental molecular mechanisms
in VHL are well known, there have been mixed
results with antibodies against these growth factors [22]. Combining ranibizumab with an antiPDGF therapy in a phase1/2 trial did not yield a
positive outcome [23].
14.2.6 Active Surveillance inVHL
Since it is not known when the lesions will start
or progress, all patients with a VHL tumour, a
family history, or a genetic test positive for VHL
should remain under active surveillance of a multidisciplinary team. See Box 14.2 (https://www.
vhl.org/clinicians/surveillance/).
abc
Fig. 14.6 A large peripheral retinal angioma (black
arrow) with extensive exudation (blue arrows) was treated
with multiple sessions of laser photocoagulation treatment (a). At 3months (b), there was a decrease in the size
of the angioma along with reduction of exudation. At
16months (c), there was near-complete regression of the
angioma and exudation
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14.3 Sturge-Weber Syndrome
Sturge-Weber syndrome (SWS) is an uncommon
neuro-ocular-cutaneous syndrome classied as one
phakomatosis. A phakomatosis is a group of neurocutaneous hamartomas that are essentially noncancerous, disorganized, self-limiting abnormal
growth of the native tissues (including connective
and vascular) in a specic body region. There are
four components of the SWS, a congenital portwine stain (PWS) (Fig.14.7), capillary hemangioma of the choroid, glaucoma, and leptomeningeal
angiomas. Secondary glaucoma complicates nearly
2/3rd of the children with facial PWS who develop
ocular-neurological signs and is a major cause of
childhood glaucoma leading to buphthalmos and
blindness. Adolescent patients may have late-onset
glaucoma [24]. Whole genome sequencing of tissue samples led to the discovery of a somatic
mosaic single nucleotide mutation (c.548G→A,
p.Arg183Gln) in the Guanine nucleotide-binding
protein G (q) subunit α (GNAQ) gene in 88% of the
SWS and 92% of the non-syndromic PWS. The
severity and the extent of the clinical manifestation
depend upon the time of the somatic mutations
[25]. This mutation has been found in the episcleral
and scleral tissue of all patients with SWS and
glaucoma [26, 27].
Fig. 14.7 Congenital port-wine stain (PWS) in a 40-yearold male patient of Sturge-Weber syndrome (SWS)
14.3.1 Sturge-Weber Syndrome—
Port-Wine Stain
Port-wine stain (PWS), a birthmark seen in 0.3%
of all newborns, is present mainly in the head and
neck, but can be present in any part of the body.
Nearly 8–10% of patients with PWS have ocular
(glaucoma) and neurological complications (epilepsy) that constitute the SWS. However, the
most prominent feature of the SWS is the presence of the PWS in the distribution of the rst
division of the trigeminal nerve-the dermatome
V1 [24]. PWS may also accompany these in the
distribution of the V2 and V3. Notably, the PWS
not involving the V1 is not associated with the
SWS. Nearly 32–65% of patients with PWS in
the V1 dermatome have ocular and/or neurological associations [28]. Although in the past, the
PWS has been described in the context of the trigeminal nerve dermatomes, it is now known that
these are purely vascular lesions and have nothing to do with nerves and hence need to be
described in the context of location rather than
dermatome [29].
The PWS, red or darker in colour and called
naevus ammeus, consists of permanently
dilated, malformed dermal vessels. The PWS
appears to follow the distribution of the trigeminal nerve dermatomes and is generally restricted
to the skin of one-half of the forehead, face, and
the ipsilateral lids (Fig.14.7). The presence of the
PWS on the upper or the lower lid carries a lifelong risk of developing glaucoma [29]. However,
bilateral lesions of PWS can be seen in 10–20%
of patients [28]. The PWS should be treated with
a pulsed dye laser in infancy[29]. The PWS must
be differentiated from benign periocular capillary
hemangiomas present at birth or in infancy in
nearly 10% of newborns. These may be strawberry nevi in the supercial dermis, which may
also be combined with a subcutaneous component, or subcutaneous nevi may be associated
with orbital hemangioma [30]. The supercial
periocular hemangiomas may appear as small
macular lesions of telangiectatic vessels that may
grow during infancy. However, a large majority
will spontaneously involute with time by
4–7years of age. In the past, ultrasonography or
ab
cd
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MRI scans were used to dene the site of these
hemangiomas. More recently, using a Swept
source Doppler Optical coherence tomography,
the malformed vessels of the PWS were found to
be 114±92μ in diameter, increasing in diameter
with their depth in the dermis compared to
39 ± 19 μ seen in the capillary hemangioma.
Although highly variable, both were seen at an
almost similar mean depth of about 300μ. The
large cavitary lesions of the PWS also showed
blood ow on Doppler. While nearly 3/4th of vessels in the hemangioma were capillaries, only
1/3rd of the vessels in the PWS were capillaries
[31]. It has been shown that compared to the noninvolved skin, vessels in the PWS are poorly
innervated by the autonomic nerve bres that
regulate the vessel diameter. Hence, the absence
of these bres leads to uncontrolled dilatation/
ectasia of these vessels [32].
14.3.2 Sturge-Weber Syndrome—
Diuse Choroidal
Hemangioma
Diffuse choroidal hemangioma (DCH) is a common association of SWS and may be seen in up to
55% of cases [33]. The fundus in diffuse hemangioma appears ‘tomato ketchup’ coloured due to
the expansion of the choroidal vasculature that
has no well-dened borders (Fig.14.8). The clinical diagnosis of diffuse choroidal hemangioma
Fig. 14.8 Diffuse choroidal haemangioma. Conventional
camera fundus photographs of right (a) and left (b) eyes
of the patient in Fig.14.7, and ultrawide eld fundus photographs of right (c) and left (d) eyes of the same patient.
The fundus in diffuse haemangioma (left eye in this case)
appears ‘tomato ketchup’ coloured due to the expansion
of the choroidal vasculature that has no well-dened borders. The clinical diagnosis of diffuse choroidal haemangioma can be a challenge and is best noted by quickly
comparing the colour of the fundus in the affected eye
(left eye in this case) with the contralateral normal eye
(right eye in this case)
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can be challenging and is best noted by quickly
comparing the colour of the fundus in the affected
eye with the contralateral eye. Diffuse choroidal
hemangioma may be bilateral in nearly 20% of
the patients with SWS, compounding the clinical
diagnosis. DCH is very commonly associated
with leptomeningeal angiomas. Thus, patients
who have PWS must undergo a retina exam to
detect it. On optical coherence tomography
(OCT), there is a loss of the usual pattern of the
choroidal vasculature, thickening of the choroid,
and loss of the choroido-scleral interface [34].
There is anecdotal evidence that photodynamic
therapy (PDT) with verteporn for diffuse choroidal hemangioma may improve vision and stabilize the hemangioma [35]. In the past, diffuse
choroidal hemangioma with symptomatic exudation was subjected to external beam radiotherapy
over 4 weeks. More recently, plaque therapy for 4
days has been found highly successful for quick
resolution of the subretinal uid in these hemangiomas [36].
14.3.3 Circumscribed Choroidal
Hemangiomas Are Not
Associated withSWS
Diffuse hemangiomas must also be differentiated
from circumscribed choroidal hemangiomas
(CCH). While DCH may be asymptomatic, both
may cause localized or diffuse exudative retinal
detachment. However, it is unusual for a CCH to
be associated with SWS.In more than 1/3rd of
the patients, CCH may be mistaken for metastatic
deposits or an amelanotic choroidal melanoma
[37]. The CCH are always a unilateral, orangecoloured solitary lesion, often located in the posterior pole. The lesion may have a pigmented
outline and some punctate white spots on the
surface, both occurring due to alterations in the
overlying RPE. Early hyperuorescence during
indocyanine green angiography and fundus uorescein angiography, and late uorescence are
highly characteristic (Fig. 14.9) [38]. On OCT
angiography, a distinct pattern of abnormal vessels can be seen in the choriocapillaris slab with
clear demarcation between the normal and the
affected area [39]. These are associated with
serous detachment of the retina (Fig.14.9). In the
past, the long-term visual outcome of treatment
with external beam radiation, plaque therapy, or
laser photocoagulation remained poor in most
eyes [37, 40]. Introducing photodynamic therapy
(PDT) with intravenous verteporn has vastly
improved the visual outcome in circumscribed
choroidal hemangiomas ([41]). Adding antiVEGF therapy to PDT may improve the visual
outcome [42].
14.3.4 Sturge-Weber
Syndrome—Glaucoma
Unilateral glaucoma is commonly associated with
SWS and may be seen in up to 71% of the patients
with this syndrome [33]. Glaucoma in SWS has a
bimodal presentation, nearly 2/3rd presenting
early in infancy or up to 2years of age with raised
intraocular pressure, open-angle, and even buphthalmos due to enlargement of the globe and cornea and corneal edema. Anterior chamber
anomalies are likely responsible for this type of
glaucoma. Nearly 1/3rd of patients with glaucoma
may present after 5 years of age or in young adolescents. The raised episcleral venous pressure is
likely responsible for raised intra- ocular pressure
in such patients. The conjunctival and episcleral
involvement is seen as dilated, and tortuous vessels are seen in up to 70% of the cases with
SWS.Electron microscopy studies in a 20-yearold woman with SWS revealed the presence of a
cluster of abnormal vessels and the accumulation
of granular extracellular matrix in the trabecular
meshwork [43]. The raised episcleral venous
pressure in patients presenting late may be due to
intrascleral or episcleral hemangioma. The veins
draining from the canal of Schelmm may likely be
draining into the hemangioma, or even the canal
of Schelmm may be a part of the hemangioma
[44]. The episcleral venous pressure in SWS-
associated glaucoma is signicantly higher than
in the normal contralateral eye [45]. Patients with
PWS remain at risk for developing glaucoma
throughout life and should have an annual checkup
of their eyes [46]. Medical management of SWS
glaucoma includes timolol maleate, and latanoprost may be effective in a small number of cases,
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ba
dc
Fig. 14.9 Circumscribed choroidal haemangioma: fundus photograph (a) showing exudative retinal detachment
(black arrows) in right eye due to a circumscribed choroidal haemangioma along the upper temporal vessels (blue
a majority requiring an Ahmed glaucoma valve
(AGV) drainage implant to normalize the pressure. Exudative and even haemorrhagic choroidal
detachments are frequent in the presence of diffuse choroidal hemangioma. Preoperative use of
oral propranolol has been found highly effective
in preventing and treating these sight-threatening
complications [47, 48].
14.3.5 Sturge-Weber Syndrome—
Neurological Associations
Nearly 80% of children with SWS develop seizures, and 75% get them before one year. Patients
with PWS in trigeminal nerve dermatomes V1
and V2 are likelier to have these than those with
arrow). OCT through macula shows serous retinal detachment (b). Fluorescein and ICG angiography show the
hyperuorescence due to the choroidal haemangioma (c,
d)
PWS elsewhere. More than half of the patients
also suffer from delayed development [49]. The
delayed development may be linked to a deciency of growth hormones in SWS [50]. In neuroimaging studies, a leptomeningeal angioma is
seen in the parieto-occipital area, which is seen
as ipsilateral to the PWS and has a strong association with diffuse choroidal hemangioma also
on the same side. A CT scan may reveal an
S-shaped calcication associated with cortical
atrophy [28]. However, the contrast-enhanced
MRI scan is superior to a CT scan for evaluating
patients with SWS [51, 52], especially for demonstrating the cortical atrophy and also the
patency and extent of the leptomeningeal angioma. In the past, it was recommended that children with SWS should have neuroimaging done
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from 6 to 12 months of age and, if positive,
should have an FDG-PET scan for initiating prophylactic anti-epileptic therapy [28]. However,
recently there has been a change in the recommendations for neuroimaging. Routine screening
for neuroimaging is not recommended in infants
and newborns with high-risk PWS but no history
of seizures or neurological symptoms. It should
be done only in select cases if prophylactic therapy is being considered [53].
14.4 Arteriovenous Malformation
oftheRetina (AVM)—
Wyburn-Mason Syndrome
Arteriovenous malformations of the retina (AVM)
are rare congenital unilateral disorders of the retinal vessels which are part of an oculo- cutaneousneurological syndrome now named after
Wyburn-Mason after a critical and detailed analysis of several anecdotal reports available; till then
was the rst to synthesize a detailed clinical account
of the AVM occurring in the midbrain where these
were most symptomatic by way of squint and intracranial haemorrhage and were seen simultaneously
in the ipsilateral retina and facial vascular nevi and
mental changes. In many cases, these were fatal
and discovered only in autopsy studies [54]. In his
review series, nearly 80% of the patients had intracranial AVM, many of whom also had subarachnoid haemorrhage. This information is likely
skewed as carotid angiography was rarely done in
his era. AVM of the retina is likely seen only in
about 8% of patients with CNS AVM [55]. The
AVMs may occasionally be seen in other brain
areas and even the orbit producing a pulsatile proptosis [56]. Rarely, an AVM may occur in the
suprasellar region and the orbit without retinal
involvement [57]. or with retinal involvement [58].
Magnetic resonance angiography may reveal a
direct communication of facial vascular nevus with
the retinal AVM and has serious visual implications
for any interventions, including embolization,
sclerotherapy, laser photocoagulation, or even the
proton beam irradiations for the communicating
facial naevi [59]. Unlike VHL disease, which has a
strong autosomal inheritance pattern, there is no
evidence that AVMs are inherited.
Moreover, there is no angioma or tumour formation. The retinal AVM arise on the optic disc
and extends into the macular area or the peripheral retina. At least three patterns were recognized by Archer etal. [60]. Type 1 AVM is seen
either in one or more than one quadrant, most
often in the macula. It has a dilated capillary network between the dilated arterioles and the draining veins. It is difcult to tell the difference
between the arteriole and the vein except on FFA,
which also shows the site of AV communication.
These do not show any extravasation of the uorescein dye and remain stable over the long term.
Type 2 AVM are high ow AV malformations
without intervening capillary bed. These are
high-ow AVM, and arteries and veins dilate
more than in type 1. Not uncommonly, the high
ow in the retinal veins may cause endothelial
damage from shear stress and cause thrombosis
[61–64].
Thrombosis may also cause spontaneous resolution of the AVM [65]. These arterioles may
develop macroanuerysmal dilatations, and some
decompensation may be seen. Although these
seem stable, the macroaneurysms may cause exudation and rupture years later with sub-retinal
haemorrhage. These may nally resolve [66].
These involute spontaneously, but in those causing exudation or haemorrhage, laser photocoagulation, or even the use of intravitreal anti-VEGF
agents may help [67, 68]. In the event of type 2
AVM in the macular area with macular edema,
anti-VEGF agents may have an inadequate
response and laser photocoagulation may help
resolve the macular edema [69, 70]. In type 3
AVM, the vessels are hugely dilated and may be
decompensated. It is difcult to tell the difference between the arteries and the veins. This type
has malformations originally described by
Wyburn-Mason and has a strong component of
AVM in the midbrain [60]. By and large, WyburnMason syndrome is an asymptomatic disorder
and is detected on routine examination. However,
it is vital to recognize these malformations as
nearly 30% of the patients may have associated
AVM in the midbrain. Unlike the AVM in the
retina, which may remain unaltered for decades,
the ones in the brain usually cause cerebral haemorrhage and may be fatal. All patients with
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Archer’s type 3 AVM in the retina should be evaluated by MR/CT angiography to rule out intracranial involvement.
14.5 Congenital Retinal
Macrovessel
Congenital retinal macrovessel (CRM) is a rare
retinal vascular anomaly characterized by a large
retinal vein that crosses the horizontal raphe in
the macula and receives blood from above and
below the horizontal raphe. Jensen drew detailed
fundus drawings of the left eye of 100 patients to
study the distribution pattern of the retinal arterioles and veins. He found a strict quadrant-wise
territorial distribution of both the retinal arterioles and the corresponding veins except in one
patient where a normal retinal arteriole crossed
the horizontal raphe [71]. The CRM vessel may
even cross the foveal avascular zone. While CRM
was rst described in the German literature in the
nineteenth century, in more recent years, it was
described by Archer etal. in 1973 as group 1 arteriovenous malformations [60].
A detailed description of these abnormal vessels was provided by Brown et al. [72], who
noted small arteriovenous anastomosis around
the fovea. Although group 1 AVM of Archer etal.
[60] had arteriovenous anastomosis between the
larger than capillary vessels, not all patients with
CRM have these arteriovenous anastomoses.
While the large, dilated veins of the CRM may be
explained by the AV anastomosis communicating
high-pressure arterial blood into these vessels
and early lling of the CRM, not all patients with
CRM show obvious anastomosis and hence
dilated retinal vein appears to be a standalone
characteristic feature of the CRM. Remarkably
delayed dye clearance in the FFA’s late frames is
seen in these vessels. There may be perivenous
capillary non-perfusion surrounding the CRM
[72]. There is no dye leakage from these vessels,
and they appear stable [73]. Systemic associations were not known earlier as non-invasive neuroimaging studies were unavailable, and invasive
arteriography was not done in the asymptomatic
patients. Compared to the general population
who show venous malformations of the brain in
0.2–6%, a review of the 10-year data from multiple centres worldwide has shown that 24% of
the patients with CRM on MRI scans had venous
malformations in the brain. Seventy–ve per cent
of the venous malformations associated with
CRM were in the frontal lobe, and most of these
were ipsilateral to the CRM.MRI scans are recommended for all patients with CRM based on
this data. Instead of the CRM, these should be
labelled as retinal venous malformations, given
their close association with cerebral venous malformations [74].
14.5.1 Retinal Cavernous
Hemangioma—Clinical
Presentations
Retinal cavernous hemangioma (RCH) is a rare,
benign, unilateral retinal angioma characterized
by a cluster of sac-like or dark-red grape-like
aneurysmal dilatations along a major retinal
vein. Rarely, the RCH may be seen on the optic
disc [75, 76]. Most RCH cases are asymptomatic and discovered on routine examination in
young adults. The RCH has no feeder vessels
unlike the retinal capillary hemangioma associated with VHL disease, which has highly characteristic dilated and tortuous feeder vessels.
Moreover, RCH is stationary and has no potential to grow or leak uid in the retinal interstitial
tissues. However, they develop brous scar tissue on the surface or rarely even a phlebolith
[77]. The RCH may get thrombosed or brosed
over time [78]. Fundus uorescein angiography
(FFA) is highly characteristic as there is a delay
in the venous lling in the affected quadrant.
There is a delayed lling of aneurysmal sacs
with the uorescein dye with late uorescence
of the supernatant plasma and blocking of the
uorescence of the bottom of the sac due to sedimented red blood cells. These features suggest
stagnant venous blood in these cavernous sacs
[75]. The optical coherence tomography shows
thin-walled large cystic cavities with a thin
epiretinal membrane stretched over these cystic
lesions [79].
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14.5.2 Retinal Cavernous
Hemangioma—Systemic
Associations andGenetics
The RCH is a part of the neuro-oculo-cutaneous
syndrome (phakomatosis) and may occur in sporadic and inherited forms. Of the three patients,
Gass [75] described a female patient presented
with RCH and multiple cutaneous angiomas. Her
father had RCH, a history of seizures, and ultimately died of a cerebral haemorrhage. His
autopsy revealed cavernous hemangioma of the
midbrain and the cerebellum. [75]. While the
cavernous hemangiomas of the skin are relatively
common because of their occurrence in association with brain stem and cerebellar cavernous
hemangioma and RCH, cavernous skin hemangiomas are likely a component of the neurooculo- cutaneous syndrome, as has also been
noted in a 4-generation pedigree of 90 members
with an autosomal dominant transmission of this
syndrome [80] and another, a 3-generation pedigree [81]. Mutations in at least three cerebral cavernous hemangiomas (CCH) genes, a point
mutation within exon 5 of KRIT19 (7q21.2), a
large deletion in MGC4607 (7p13), and complete
deletion of PDCD10 (3q26.1) have also been
noted in patients with RCH [82, 83]. Nearly, 5%
of the patients with familial cavernous hemangioma of the brain have RCH [83], whereas 14% of
all the RCH patients had CCH, most of whom
were asymptomatic [84]. Compared to computerized tomography, magnetic resonance imaging
(MRI) of the brain is far more sensitive in detecting these malformations. Multiple lesions may be
seen in the familial forms of the CCH, compared
to the sporadic variety, which has a solitary lesion
[85]. Moreover, various MR imaging techniques
have been used to improve the localization of
these lesions [86].
the OCT shows a brous membrane stretched
over the surface of the thin-walled RCH cystic
lesions. Contraction of this membrane may
explain why a vitreous haemorrhage occurs spontaneously or following a minor trauma [79].
However, spontaneous or birth trauma-related
vitreous haemorrhages are rarely reported [79,
87–89]. A unique case of RCH was followed up
from birth to the age of 52 with recurrent vitreous
haemorrhages, and hyphema, ultimately leading
to a painful blind eye. The eye was ultimately
removed and subjected to histopathology. The
RCH consisted of large endothelial cell-lined
vascular channels typically seen in cavernous
hemangioma. The RCH was seen extending into
the ciliary body and was responsible for recurrent
hyphema in this patient [90].
14.5.4 Retinal Cavernous
Hemangioma—Treatment
A majority of the RCH do not require any treatment. However, in patients with recurrent vitreous haemorrhages, one may consider either
cryotherapy, PDT, or plaque radiation (https://
retinatoday.com/pdfs/0715RT_Mini_Shields.
pdf). However, patients with RCH should
undergo MRI to rule out any asymptomatic or
symptomatic CCH [91]. The CCH are circumscribed and can be excised by neurosurgeons, and
those located in deep inaccessible areas can be
treated with stereotactic radiosurgery.
14.6 Retinal Astrocytoma
14.6.1 Hamartomas-Tuberous
Sclerosis
Complex—Introduction
14.5.3 Retinal Cavernous
Hemangioma—Complications
By and large, the RCH remains unchanged over
decades. Occasionally, however, they may
develop vitreous haemorrhage. As noted above,
Hamartomas are uncommon congenital benign
growths of a mixture of various cells and tissues
found in their normal place. The tuberous sclerosis complex (TSC) is a neuro-oculo-cutaneous
autosomal dominant disorder (9q34.13 mutation
in the gene TSC1/2) with the development of
hamartomatous growths in multiple organs, the
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