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

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Monthly intravitreous injections of anti-VEGF (Lucentis*) were continued for 9 months and the response to treatment was evaluated with visual acuity, OCT, fluorescein and ICG angiography.

The patient demonstrated reliable compliance with fol- low-up and injections. This treatment initially achieved a good result but each attempt to defer injections was followed by recurrences of variable severity.

During these 9 months of follow-up, treatment maintained the lesions to a limited stage, and the pathology always remained sensitive to anti-VEGF therapy (Figure 5).

9Visual acuity was relatively good, but the patient experienced changes in visual acuity after a maximum of two months between injections.

At the last follow-up, VA remained stable at 20/63, allowing satisfactory reading. Maintenance treatment with alternating ranibizumab and pegaptanib was considered.

Spectralis* OCT

▬By the first follow-up examination, the retinal thickness had decreased considerably to almost normal. The vertical cross-section, selected exactly over the lesion detected by fluorescein angiography, showed almost complete resolution of the intraretinal lesion

(Figure 5a).

Only a few large bright hyper-reflective spots and disruption of the IS/OS interface and external limiting membrane were still present.

▬Two months later, the situation appeared to have improved with VA of 20/50 and barely detectable lesions, with similar features but attenuated and more localized (Figure 5b).

▬Two months later, the patient experienced a recurrence. The OCT appearance was identical to the initial findings: discontinuity of the RPE, disruption of the outer layers, intraretinal extension, fluid accumulation, and numerous bright hyper-reflective spots (Figure 5c).

▬After another injection, the features improved immediately, but another recurrence was observed 2 months later with return of the same fluorescein angiography, ICG angiography, and OCT signs (Figure 5d).

▬The last examination showed a satisfactory appearance.

Retinal layers were well-organized, with normal thickness and regression of the signs, even at the site of the original lesions.

Several bright hyper-reflective spots, occasionally confluent, were still visible (Figure 5e).

Fluorescein Angiography

The small (300 μm) hyper-fluorescent zone remained visible but became almost punctate during phases of improvement (Figure 5a and b).

Each relapse was marked by reappearance of fluorescein leakage but with no new hemorrhage and no change in the numerous adjacent drusen.

Dark hypo-fluorescent lipofuscin material was visualized in the foveal region.

ICG Angiography

The dark PED remained small, poorly-delineated, and with poor contrast.

Choroidal neovascularization was barely visible with no marked neovascular membrane (Figure 5a-d).

FA

Recurrence Æ IVT-4

20/80

During follow-up of this case, a calliper placed on the angiogram allowed simultaneous visualization of the corresponding lesion on the OCT cross-section together with graphic representation of retinal thickness

A numerical representation of retinal thickness at the green line selected with the calliper was also displayed.

At each subsequent examination, retinal thickness was obtained by a simple click with automatic alignment on the lesion selected at the first examination.

In this particular case, follow-up demonstrated very rapid and spectacular improvement after the first injection (green zone on the graph) (Figure 6 a and b).

Subsequently, at the time of recurrence, retinal thickness returned to the pretreatment value (Figure 6c and d).

Finally, after the 4th injection, retinal thickness returned to normal (260 μm, i.e. 166 μm less than on the initial examination).

A 95-year-old woman with bilateral AMD progressing over many years and monocular blindness (due to longstanding chorioretinal anastomosis in the right eye) presented with a recent, moderate decline of visual acuity in the left eye.

VA RE: 20/320 – VA LE: 20/50.

Biomicroscopic examination revealed a few disseminated soft drusen and a highly suggestive, small juxtafoveal hemorrhage at 5 o’clock, (Figure 8, color).

Fluorescein Angiography

▬ Small zone (200 μm) of early hyper-fluorescence adjacent to the macular termination of retinal ves-

9sels with fluorescein leakages partially masked by hemorrhage (Figure 7a).

▬In the late phase, progressive filling of a small PED and the overlying SRF with numerous cysts (Figure 7b).

SLO-ICG Angiography

a): Early phase: small, round, juxtafoveal hyper-fluores- cent lesion.

The enlarged image more clearly visualized the end-to- end retino-retinal anastomosis between a retinal arteriole and a retinal venule and a direct communication between retinal vessels and a deeper, small choroidal neovascularization (Figure 7c).

b): Late phase: dark, hypo-fluorescent, low-density PED containing a zone of hyper-fluorescent choroidal neovascularization (Figure 7d).

Suggested Diagnosis:

Early chorioretinal anastomosis with active fluorescein

leakage and a small serous PED.

Horizontal cross-section

Characteristic and immediately suggestive appearance:

▬Discontinuity of the RPE, disruption of the external limiting membrane, alteration of the IS/OS interface,

▬Presence of a pre-RPE dense zone and numerous bright hyper-reflective spots,

▬Marked intraretinal fluid with numerous small cysts in two layers.

The chorioretinal anastomosis was visualized as a hyperreflective zone appearing to arise from the choroid and protruding anterior to the RPE.

The retinal hemorrhage induced a juxtafoveal hyperreflective zone in the inner layers with characteristic shadowing (Figure 8a).

The vertical cross-section centered on the hyper-fluores- cent zone demonstrated the same characteristic signs: disruption of the RPE and clearly visible protrusion of CNV into the retina (Figure 8b).

Stratus* TD-OCT cross-sections showed the same lesions but with much less detail (Figure 8c and d).

▬Anterior to the RPE, increased retinal thickness with subretinal and intraretinal fluid and numerous cysts.

▬The outer retinal layers were severely altered over the zone of protrusion of the CNV with numerous bright hyper-reflective spots.

A long course of intravitreous injections of anti-VEGF was planned with monthly follow-up of visual acuity, OCT, and fluorescein and ICG angiography.

However, this elderly patient elected to suspend her treatment after the third injection when she obtained subjectively satisfactory stabilization.

During these 4 months of follow-up, the various imaging modalities demonstrated partial regression of the lesions that appeared to respond to treatment without completely

resolving (Figure 9).

9

This patient’s visual acuity stabilized at 20/125 with subjective improvement of functional disability.

Spectralis* OCT

By the first examination, the lesion appeared to decrease in size, although retinal thickness remained markedly increased.

Horizontal cross-section

All of the initial signs were still present but less marked: disruption of the RPE, hyper-reflective zone anterior to the RPE, numerous cysts in two layers, and multiple bright hyper-reflective spots (mainly around the zone of intraretinal fluid).

The localized zone of juxtafoveal hyper-reflectivity corresponding to hemorrhage persisted with shadowing ex-

tending throughout the choroid. All these signs were less marked than on the initial examination.

Vertical cross-section

The appearance on the vertical section was just as diagnostic with disruption of the RPE, intraretinal fluid, and juxtafoveal hemorrhage. The numerous bright hyperreflective spots indicated that the lesion was still active despite a relative improvement (Figure 10a and b).

Graphic thickness representations

Comparison of the same location as on the initial examination with two graphs of the horizontal and vertical cross-sections showed a slight increase of retinal thickness despite attenuation of the patient’s symptoms (Figure 11a and b).

Fluorescein Angiography

The neovascular membrane and anastomosis were less well perfused and initially masked by retinal hemorrhage. In the late phase, several fluorescein leakages were visible beyond the hemorrhage with almost no staining or cystoid edema (Figure 9a and b).

ICG Angiography

The neovascular membrane was not clearly visualized and the retino-retinal anastomosis was barely visible. The dark area, indicative of PED, remained visible but presented low contrast (Figure 9c and d).

a

b

Hemorrhage

Fluid

Shadowing

Cystoid Spaces

Hyper reflective Zone

An 86-year-old woman with AMD, predominantly affecting the left eye and evolving slowly for several months, presented with loss of visual acuity.

VA RE: 20/50 – VA LE: 20/160.

Biomicroscopic examination demonstrated highly suggestive pigment migrations forming a network, several perifoveal soft drusen, and most notably, a small juxtafoveal hemorrhage at 5 o’clock (Figure 13a, color).

On autofluorescence, the pigmented network was autofluorescent and xanthophyll pigment was normal.

Fluorescein Angiography

▬ Early phase, minimal hyper-fluorescent, juxtafoveal

9lesion at the termination of a retinal venule, which was partially masked by hemorrhage (Figure 12a).

▬Late phase, the lesion was rapidly masked by staining of the material (Figure 12b).

SLO-ICG Angiography

a)Early phase: the deep, round, hyper-fluorescent, juxtafoveal neovascular membrane was immediately visible. The enlarged view clearly demonstrated that the lesion was in contact with a terminal retinal venule (Figure 12c).

b)Late phase: the initial juxtafoveal lesion was visualized within the dark, hypo-fluorescent PED with irregular margins. It was associated with a large hyper-fluorescent area that invaded almost all of the surface of the PED (Figure 12d).

Suggested Diagnosis:

Chorioretinal anastomosis associated with PED almost

completely invaded by choroidal neovascularization, in-

dicating a chronic lesion.

Horizontal cross-section

The horizontal cross-section showed the inferior part of the PED and the autofluorescent lesions.

The RPE was irregular and thickened due to deposits.

It was also elevated and separated from Bruch’s membrane, demonstrating the vascularized PED.

Anterior to the RPE, OCT showed

▬Disruption of the external limiting membrane,

▬Alteration of the IS/OS interface,

▬Presence of a pre-RPE dense zone,

▬Several bright hyper-reflective spots,

▬Marked intraretinal fluid, and

▬Numerous, and small, tightly packed cysts.

The neurosensory retina was also globally thickened (Figure 12a).

Vertical cross-section

The vertical cross-section centered directly over the hemorrhage and the neovascular lesion immediately demonstrated characteristic signs: discontinuity of the RPE and clearly visible protrusion of CNV into the retina (Figure 12b).

Anterior to the RPE, increased retinal thickness with subretinal and intraretinal fluid and a large number of cysts. The outer retinal layers were altered over the protrusion of CNV with numerous bright hyper-reflective spots. The severely altered outer nuclear layer was no longer detectable in the central retina.

The hyper-fluorescent zone in the inner retinal layers was visualized simultaneously on ICG angiography and by the vertical line on OCT. The hyper-reflective zone corresponded to the juxtafoveal retinal hemorrhage with shadowing extending as far as the choroid.