Ординатура / Офтальмология / Английские материалы / Optical Coherence Tomography in Age-Related Macular Degeneration_Coscas_2009

Intravitreal anti-VEGF therapy (Lucentis*) was monitored for a period of almost two years.

Visual acuity improved progressively after each of the six intravitreal injections to reach 20/25 (score: 81), which remained stable over the next six months. The patient was again able to read, one year after starting treatment (Figure 49).

OCT

At the First Follow-up Examination

8Despite functional improvement, the OCT remained relatively unchanged: the PED decreased, but the hyper-

reflectivity anterior to the RPE and the moderate intraretinal fluid persisted (Figure 49a).

During the first year

The course was favorable, with slow, regular improvement of visual acuity from 20/63 to 20/50, and then to 20/40 and 20/32. The vascularized PED remained visible, fairly flat, and partially organized, while thickening of the RPE resolved.

The IS/OS interface and external limiting membrane were visible but disrupted. The outer nuclear layer remained very irregular, with denser and slightly hyper-reflective zones. Retinal thickness gradually decreased but did not return to normal (Figure 49b).

Subsequent follow-up examinations were performed every 3 months, or more frequently, often at the time of treatment of the fellow eye. The improvement of visual

acuity was maintained and remained stable at 20/25. The OCT appearance improved.

At the 15th Month

The PED persisted with irregularities of the RPE and hy- per-reflectivity of the PED cavity in the subfoveal zone. A small SRF remained visible on SD-OCT, possibly related to alterations of the RPE.

Outer retinal layers were clearly distinguishable and regular with persistent thickening of the IS/OS interface and jagged irregularities of the outer nuclear layer with a few rare bright hyper-reflective spots (Figure 49c).

At the last Follow-Up Examination

The OCT features remained stable 6 months after stopping intravitreal injections to the left eye.

The retinal layers had an almost normal appearance, apart from several irregularities of the outer nuclear layer and significant thickening of the IS/OS interface over the residual SRF with irregularities of outer segments (Figure 49d). Note that the posterior vitreous was detached.

Angiography

Fluorescein angiography: the radial folds became smaller and gradually faded. The hyper-fluorescent occult CNV and pinpoint leakage persisted but became smaller and less intense.

ICG angiography: the dark PED was replaced by a weakly fluorescent late plaque. The neovascular membrane was poorly visible and limited to large vessels (Figure 49).

At this Stage

This case of a partially retracted vascularized pig-

ment epithelium detachment with radial folds, largely invaded by a neovascular membrane with fi-

brosis, was identified and treated at a very advanced

stage.

The response to treatment was very slow but favor-

able, with more rapid improvement after the 3rd IVT,

justifying continuation of treatment until stabiliza-

tion, obtained after the 6th injection.

At the last examination, the morphology of the neuro-

sensory retina was almost normal, despite persistence

of a small SRF and several alterations of outer segments, probably related to the prolonged course.

The PED persisted almost unchanged with moderate fibrosis. Inner and outer retinal layers were clearly visible

and well-organized, accounting for the good visual acuity.

The prognosis was favorable at this stage, but quarterly

and half-yearly observation remained essential.

Occult choroidal neovascularization can be associated with major hemorrhagic complications that can sometimes be the first signs of a lesion that has slowly advanced over a long period of time. These hemorrhagic complications can occur with no apparent cause. They often present as a sub-macular hemorrhage measuring several disc diameters and may sometimes be very extensive, extending as far as the temporal arcade or beyond, inducing sudden severe loss of visual acuity.

8This subretinal hemorrhage can be treated surgically to slide the hematoma inferiorly (with air bubble and po-

sitioning), or it can be surgically evacuated, sometimes with useful results, but the indications have not been

clearly defined. When the hemorrhage is behind the RPE, these treatments may be ineffective or even deleterious. In many cases, intraretinal and subretinal hemorrhage and hemorrhagic pigment epithelium detachment are related to an RPE tear, often in the temporal sector. In this situation, the hemorrhage usually has a suggestive arcuate shape, masking the tear and the associated choroidal neovascularization.

Fundus imaging is particularly useful in all of these cases, especially SLO-ICG angiography, which can cross a relatively thin layer of blood, and OCT, which can demonstrate the tear and the type of neovascularization (Figures 50, 51, and 52).

Clinical Signs

An 88-year-old woman, previously followed for AMD, presented with sudden loss of vision in her left eye with a central scotoma. VA RE: 20/40 - VA LE: 20/200.

Biomicroscopic Examination

The first examination of the left eye demonstrated a very large, arcuate shaped hemorrhage in the temporal macula. The blood was subretinal with another less marked and deeper paracentral hemorrhage (Figure 53a).

8

Fluorescein Angiography

The early phases demonstrated a well-delineated zone of very intense hyper-fluorescence with marked fluorescein leakage and a thin dark crown of hemorrhage around this zone

This area was situated in a larger, poorly-delineated area of delayed hyper-fluorescence with pinpoint leakage and

late fluorescein leakage. These findings were suggestive of an occult CNV and vascularized PED, at the edge of which an arcuate-shaped hemorrhage was observed (Figure 53b).

SLO-ICG Angiography

The area of classic CNV stained rapidly but with early washout. The vast area of occult CNV was stained later with a deep neovascular membrane clearly visible against the dark background of the PED (Figure 53c).

Suggested Diagnosis:

Vast area of occult CNV in a vascularized PED with

a small area of classic CNV (minimally classic) and

recent development of an extensive arcuate hemorrhage at the edge of the vascularized PED, suggesting

an RPE tear.

Spectralis* horizontal section

The RPE was markedly elevated and separated from Bruch’s membrane, forming an optically empty pigment epithelium detachment. The temporal part of the RPE was suddenly disrupted (tear) with retraction of the

RPE.

Only Bruch’s membrane was visible throughout the zone of the old PED. The RPE was only visible further away from the PED. The zone exposed by the tear, and retraction of the RPE presented intense posterior shadowing.

Anterior to the RPE, the IS/OS interface was masked by a hyper-reflective zone, corresponding to hemorrhage. This hemorrhage extended beyond the tear (and masked the tear on angiography). A large SRF was visible in the area of the RPE tear (Figure 53d).

Spectralis* vertical section

The section passed through the most temporal part of the PED, which was masked by hemorrhage.

The residual PED was clearly visible together with the RPE tear and the zone in which Bruch’s membrane and the choroid were exposed, together with subretinal fluid.

A vast hyper-reflective zone corresponding to retinal hemorrhage was observed anterior to the RPE

The external limiting membrane and IS/OS interface were visible with bright hyper-reflective spots and thinning of the outer nuclear layer.

The inner retinal layers were only slightly altered (Figure 53e).

Chapter 8 · Clinical Features and Natural History of AMD on OCT

HEMORRHAGIC COMPLICATIONS

d

V-PED

e

ICG

O-CNV c

RPE Tear

Hemorrhage

Bruch’ Membrane

Clinical Signs

An 82-year-old woman had been followed previously for AMD for several years, with major changes in both eyes. Both eyes developed irreversible central scotomas despite various treatments.

The patient presented with progressive loss of visual acuity and with the hope of a new treatment.

VA RE: 20/800 - VA LE: 20/400.

ited fluorescein leakage except at the periphery. A central hypo-fluorescent zone was suggestive of accumulation of material.

Diffuse alterations of the RPE were also observed with abnormal transmission of fundus fluorescence all around the central area.

SLO-ICG angiography (Figure 54c)

Biomicroscopic Examination

8Examination of the left eye revealed a poorly-demarcated, discolored, extensive 4 DD lesion with several peripheral

retinal hemorrhages. The lesion was relatively flat except in the superior temporal sector (Figure 54a).

On autofluorescence, the lesion was dark, suggesting moderate but extensive atrophy with a large peripheral hyper-fluorescent halo and visible hemorrhages.

Fluorescein angiography (Figure 54b)

Fluorescein angiography showed an early and moderate hyper-fluorescent zone with progressive staining but lim-

The large choroidal vessels were abnormally visible. The lesion was extensive, hypo-fluorescent, and clearly demarcated, except in the peripheral active lesions, visible against the dark background of the PED.

Suggested Diagnosis:

Old, extensive lesion, essentially in the process of atro-

phy but with active lesions in the periphery and persis-

tent symptoms.

Spectralis* horizontal section

The RPE was irregular and thinned with zones of variable density. The RPE was separated from Bruch’s membrane over the entire surface of the lesion with a flat, organized, moderately reflective vascularized PED.

Anterior to the RPE, the external limiting membrane and IS/OS interface were not visible. The outer nuclear layer no longer visible in the foveal zone, appeared to be invaded by an irregular zone of increased density with scattered bright hyper-reflective spots.

Increased retinal thickness, intraretinal fluid, and cysts induced major disorganization of the retinal structure (Figure 53d).

Spectralis* vertical section

This section visualized the flat and organized vascularized PED, the marked changes of the outer retinal layers with bright hyper-reflective spots, dense zones, cysts, and increased retinal thickness.

The inner retinal layers were only slightly altered (Figure 53e).

Stratus* horizontal section

This section confirmed the increased retinal thickness, cysts, and SRF, but the flat vascularized PED was not visible (Figure 53f).

The response to treatment by intravitreous injections of anti-VEGF (Lucentis*) was monitored in terms of functional results and imaging before each injection.

Unfortunately, visual acuity ended up stable at 20/320 despite a slight initial improvement.

The patient’s metamorphopsias resolved, and she started low vision rehabilitation (Figure 54).

8

OCT

The first follow-up examination demonstrated a slight improvement and all of the outer nuclear layer was clearly visible, although displaced and raised by dense material with bright hyper-reflective spots and several cysts (Figure 54a).

At the 6th month, no functional improvement was observed despite a 4th injection. Bruch’s membrane was clearly visible, and the flat, organized PED remained unchanged (Figure 55b).

At this Stage

This case of longstanding, extensive occult CNV in the

process of atrophy, with active lesions at the periphery was treated due to the presence of several signs of activity, despite the long history of the lesions.

In view of the poor visual acuity in the fellow eye, repeated intravitreous injections were administered for 6 months.

No functional improvement was obtained. However,

the intraretinal fluid and reactive inflammatory signs (bright hyper-reflective spots and dense zones) faded

and then resolved.

Anterior to the RPE, the outer layers were disorganized and the IS/OS interface was only occasionally visible.

The outer nuclear layer was altered with numerous persistent bright hyper-reflective spots with a partially retracted epiretinal membrane.

At the 9th month (Figure 55c)

The OCT appearance was practically unchanged with decreased retinal thickness and bright hyper-reflective spots.

At the last examination (Figure 55d)

Six months after the last IVT injection, all of the retina was thinned, especially in the foveal region with thinning of the RPE and loss of the outer retinal layers.

The outer nuclear layer was in contact with the atrophic RPE, suggesting photoreceptor atrophy. These alterations were clearly visible on enlarged views (Figures 56a and b).

Angiography (Figure 55)

The lesion remained the same size, but fluorescein leakage and hemorrhages had resolved. Atrophy was clearly visible on ICG angiography.

The inner retinal layers regained a normal structure,

but with thinning of all of the retina, corresponding to

atrophy of inner and outer segments, clearly visible on SD-OCT and justifying discontinuation of treatment.

By stopping extension and exudation, treatment was nevertheless useful, but it did not provide any improvement of visual acuity due to the longstanding nature of the lesions.

Low vision rehabilitation would be considered useful for this patient.