Ординатура / Офтальмология / Английские материалы / Fluorescence Angiography in Ophthalmlogy_Dithmar, Holz_2008

8.1.7 Pigmented Optic Disc Anomalies

the congenital, pigmented anomalies of the optic disc include the juxtapapillary combined hamartoma of the retina and pigment epithelium and the melanocytoma, a very uncommon, pigmented hamartoma. These two benign entities must be distinguished from the uveal melanoma with optic disc involvement.

Fundus

The juxtapapillary combined hamartoma of the retina and the retinal pigment epithelium is an irregular pigmentation in the region of the optic disc and the surrounding retina with glial proliferation and vascular ectasias. The changes are sharply margined and relatively flat. Glial cell

8proliferation and hyperpigmentation are found on the retinal vessels, which can be partially ob-

scured and distorted by the process. The melanocytoma is a very darkly pigmented tumor in the area of the optic disc which in some cases can be very prominent. In contrast to the uveal, parapapillary, malignant melanoma, there is no peripapillary retinal detachment.

Fluorescein Angiography

The juxtapapillary, combined hamartoma of the retina and the retinal pigment epithelium causes a blockage of background fluorescence by its hyperpigmentation and glial cell proliferation. The pronounced capillary ectasias and distorted retinal vessels are clearly revealed. In the late phase there is some leakage of dye from the ectatic vascular segments. The melanocytoma also causes a blockage of the normal papillary fluorescence. Contrary to the uveal malignant melanoma, the malanocytoma has no intrinsic vascular structure.

Fig. 8.10a–d. A 44 year old patient with coincidental discovery of a juxtapapillary combined hamartoma of the retina and retinal pigment epithelium in the left eye. Acuity 20/20. a Fundoscopy finds delicate pigmentation and glial cell proliferation in

the region of the optic disc and the peripapillary fundus. The peripapillary vessels are distorted, which becomes clearly apparent b–d during fluorescein angiography. In the late phase there is a subtle leakage of dye coming from the distorted vascular segments.

Fig. 8.11. A 23 year old patient with a melanocytoma of the optic disc (right eye). There is a flat, rather dark pigmentation with no associated serous

retinal detachment. These findings have been stable for 5 years. The patient has no vision problems; the acuity is 20/20.

8.2Anterior Ischemic Optic Neuropathy

Anterior ischemic optic neuropathy (AION) is the result of a failure of perfusion of the prelaminar optic disc. Underlying problems can be primarily arteriosclerotic or inflammatory processes (temporal arteritis). The hypoxic damage to axoplasmic flow causes swelling of the ganglion cell axons: papilledema. Depending on the severity of

the process, splinter hemorrhages can appear in the nerve fiber layer.

Autofluorescence / Fluorescein Angiography

The swollen axons cause a blockage of both the autofluorescence and the peripapillary background fluorescence. Perfusion of the optic disc can be delayed. In the area of papilledema there are capillary ectasias. In the late phase there is leakage of dye into the swollen tissue of the optic disc.

Fig. 8.12a–e. A 67 year old patient 2 hours after the abrupt onset of visual loss in the right eye, caused by AION. He has been treated for arterial hypertension for the past 10 years. a Fundoscopy shows a relatively pale, swollen optic disc with blurred margins. The papilledema is most prominent in the superotemporal sector of the disc. A choroidal nevus is also seen, located inferonasal to the optic disc. b Autofluorescence imaging. In the region that includes the optic disc swelling there is blockage of

the autofluorescent phenomenon. c–e Simultaneous fluorescein angiography (left half images) and ICG angiography (right half images): The disc swelling blocks the peripapillary background fluorescence. In the early phase there is a delayed perfusion of the optic disc, particularly in the superotemporal sector. There are dilated capillaries on the surface of the optic disc. In the late phase e of the fluorescein angiogram there is leakage of dye which is bounded by the area of optic disc swelling.

8.3Papillitis

Papillitis is a circumscribed inflammation of the optic disc that has a highly varied group of possible underlying causes. Clinically there is a blurring of the margin and a prominence of the optic disc. The swelling of the disc tissue can interfere with blood flow in the retinal vessels, leading to central retinal vein occlusion.

Autofluorescence / Fluorescein Angiography

In the region of disc edema there is a reduction in the normal autofluorescence signal and during fluorescein angiography there is a blockage of the normal background fluorescence. During the course of the angiogram dilated capillaries appear on the surface of the disc. The late phase shows leakage of dye bounded by the swollen disc.

a

Fig. 8.13a–e. A 39 year old patient with left sided

Papillitis and loss of acuity to 20/400 for the past week. Cranial MRI and laboratory values are unremarkable. a Fundoscopy shows optic disc edema with circumscribed nerve fiber layer hemorrhages inferiorly and secondary dilation of the retinal veins. b The normal peripapillary autofluorescence is blocked

b

in the area of disc edema. c–e Simultaneous fluorescein angiography (left half images) and ICG angiography (right half images): In the course of the angiogram there are increasing numbers of telangiectatic and altered capillaries in the region of disc swelling. In the late phase there is demonstration of fluorescein leakage bounded by the edematous disc.

8.4Papilledema

Papilledema arises when there is elevation of the intracranial pressure. The associated elevation of pressure in the optic nerve sheaths leads to interference with axoplasmic flow, the consequence of which is a swelling of the axons. The swelling of the optic disc tissues causes the neuroretina to be displaced, causing an enlargement of the physiological blind spot.

Autofluorescence / Fluorescein Angiography

Papilledema leads to a reduction of the normal peripapillary autofluorescence signal and in the fluorescein angiogram it leads to a blockage of the background fluorescence. Angiography shows the dilated capillaries in the swollen disc tissue, and in the late phase there is leakage of dye bounded by the edematous disc.

Fig. 8.14a–e. A 52 year old patient with pseudotumor cerebri and bilateral papilledema. Acuity has been reduced to in both eyes to 20/30. a Left eye: distinct papilledema with blurring of the disc margins and dilation of the central veins. Associated findings include isolated perimacular zones of RPE atrophy. b Autofluorescence imaging: The optic disc margins are blurred, since the papilledema in part blocks the normal parapapillary autofluorescence.

c–e Simultaneous fluorescein angiography (left half images) and ICG angiography (right half images):

During the angiogram there is demonstration of dilated capillaries on the surface of the swollen optic disc. d An associated finding are hyperfluorescent zones correlating with the areas of RPE atrophy. In the late phase e fluorescein leakage appears in the region of the swollen disc tissue.

8.5Parapapillary Choroidal Neovascularization

Choroidal neovascularization (CNV) can arise directly at the margin of the optic disc, and the temporal side of the disc is the usual point of departure in formation of a CNV membrane. There are many known predisposing factors. These include age-related macular degeneration ( Chapter 5), angioid streaks ( Chapter 5), optic disc anomalies ( Chapter 8.1), and prior inflammatory disease activity (POHS, chorioretinitis, Chapter 7).

Symptoms

The disease is particularly noticed by the patient when fluid exudation originating in the CNV

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reaches the region of the papillomacular bundle, extending to the foveal retina.

Fundus

At the papillary border there appears a prominent gray-white subretinal lesion that is in varying degrees accompanied by subretinal hemorrhages and surrounded by lipid exudation. The neighboring margin of the optic disc is often blurred.

Fluorescein Angiography

As in the CNV lesions that occur in other locations ( Chapter 5) there is a parapapillary CNV that is hyperfluorescent during the course of the angiogram. In the late phase there is a clearly visible leakage of dye from the CNV lesion.

Fig. 8.15a–d. A 70 year old patient with parapapillary CNV in the right eye. a Fundoscopy shows temporal blurring of the optic disc margin, caused by an exudative subretinal process temporal to the optic disc. Isolated subretinal hemorrhages are visible. The process is bounded by a pigmented line that extends to the fovea. b Autofluorescence imaging shows a blockage of the normal autofluo-

rescence in the region of the CNV. c Fluorescein angiography shows a clearly defined choroidal neovascular membrane temporal to the optic disc. The CNV shows the elements of a classic CNV ( Chapter 5.1.4.1) with a hyperfluorescent margin and a small neighboring zone of hypofluorescence. In the late phase d there is clearly visible leakage of dye from the CNV membrane.