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

The response to treatment of monthly intravitreal injections of anti-VEGF (Lucentis*) was monitored with visual acuity, OCT, fluorescein angiography, and ICG angiography.

Each injection was administered as indicated, which was followed by an immediate and dramatic improvement in retinal architecture (Figure 33).

After the first injection, visual acuity was moderately improved but with a marked improvement of visual symptoms.

8

OCT

By the first examination, dramatic improvement was demonstrated, with reduction of retinal thickness and a complete and rapid resolution of the large foveal and juxtafoveal intraretinal cysts.

On the horizontal section, resolution of intraretinal fluid and restoration of a normal and symmetrical foveal depression.

The inner and outer retinal layers became clearly visible. The outer nuclear layer was constantly visible and was only thinned over the classic CNV. The external limiting membrane was distinguishable with a normal appearance.

The only residual sign after resolution of classic CNV was the localized zone of hyper-reflectivity between the external limiting membrane and the IS/OS interface with thickening of the IS/OS interface (Figure 33).

In the inferior part of the vertical section, persistence of the vascularized PED still extended as far as the foveal region, but with a normal appearance of retinal layers.

Fluorescein Angiography and ICG Angiography

On fluorescein angiography, classic CNV regressed immediately with only minimal fluorescein leakage.

ICG angiography showed low perfusion of the classic CNV, but the occult CNV remained clearly visible and appeared to have become larger, justifying a second IVT injection.

Six Months Later

The situation remained stable and did not warrant any further IVT injections. VA had improved to 20/32.

Spectralis* OCT examinations confirmed resolution of intraretinal fluid and normalization of outer retinal layers.

Only the persistence of a hyper-reflective band anterior to the RPE suggested residual fibrosis of classic CNV.

The external limiting membrane was clearly visible with no hyper-reflective bright spots (Figure 34).

However, the vertical section showed a wavy, irregular, and relatively flat residual PED with a moderately reflective cavity, suggesting partial organization.

The external limiting membrane was normal but several irregularities were visible in the outer nuclear layer, which was thinned over the dome of the PED.

Autofluorescence photographs showed persistence of a superior temporal lesion but sparing the central macula.

Angiography confirmed the stabilized and scarred appearance of the lesion (Figure 34).

Residual Fibrosis

6 month later

External limiting membrane

a

6 months later

b

Clinical Signs

A 73-year-old man was followed for wet AMD of his left eye, which had been treated by PDT.

Autofluorescence showed a fairly large but regular perimacular halo of hyper-fluorescence (Figure 37a and b).

Fluorescein angiography (Figure 37c and d):

In the absence of symptoms and with normal visual acuity, routine assessment of the right eye demonstrated the presence of an extrafoveal area of classic choroidal neovascularization measuring 1 DD, more than 1500 μm from the center. This lesion was successfully treated by a single session of thermal laser, without recurrence and

8with a good scar that remained stable for half a year.

After about 6 months, the patient reported slowly progressive visual discomfort that became more marked during the following month, with the appearance of angiographic signs of recurrence (occult CNV), justifying a full evaluation and a treatment decision.

VA RE: 20/32 - VA LE: 20/125.

Biomicroscopic Examination

The laser scar was stable and unchanged. A grayish zone was observed on the foveal edge of the scar, extending onto the fovea. Several soft drusen were observed, with no hemorrhage or lipid exudates.

▬The laser scar was hypo-fluorescent with regular margins, which disappeared into the fovea.

▬A zone of moderate, progressive hyper-fluorescence was observed throughout the superior nasal region of the macula with minimal fluorescein leakage. Disseminated area of pinpoint leakage, suggested deep occult CNV with no cysts.

SLO-ICG angiography (Figure 37e and f):

a): Early phase: vast zone of macular and superior temporal hypo-fluorescence crossed by several large choroidal vessels which were in contact with the atrophic laser scar. b): Late phase: more marked hypo-fluorescence, suggesting an oval-shaped juxtafoveal and subfoveal vascularized

PED.

Suggested Diagnosis:

Post-laser recurrence in the form of occult CNV after a

long phase of stability.

Section through the center of the fovea: The RPE was raised and irregular in the juxtafoveal and nasal areas. Within and anterior to the RPE, marked increase of retinal thickness with large intraretinal cysts (Figure 38).

The moderately raised, juxtafoveal and nasal vascularized pigment epithelium detachment was well demonstrated from below with cysts. A small amount of subfoveal fluid was also demonstrated (Figure 38).

The response to treatment by monthly intravitreous injections of anti-VEGF (Lucentis*) was monitored with visual acuity, OCT, fluorescein angiography, and ICG angiography.

The decision to inject was made according to the clinical presentation and resulted in an immediate improvement of VA to 20/25 that was maintained throughout the 15 months of follow-up (Figure 39).

8

OCT

By the first follow-up examination, there was reduction of retinal thickness with almost complete resolution of the large intraretinal cysts, but persistence and even enlargement of the inferior foveal and juxtafoveal SRF on the vertical section (Stratus OCT).

The third and fourth intravitreous injections were therefore performed due to persistence of this intraretinal fluid (Figures 39a and b).

The Spectralis* vertical section showed marked improvement with normal retinal thickness, but persistence of numerous bright hyper-reflective spots in the outer layers and at the edge of the inferior SRF (Figures 39b and c).

At the ninth month, the examination appeared to be almost normal with a very flat PED and good visibility of the external limiting membrane and IS/OS interface. Almost all of the outer nuclear layer had become regular despite scattered bright hyper-reflective spots (Figure 39c).

At this Stage

This post-laser recurrence in the form of occult CNV, after a remission interval of six months, evolved very

slowly and progressively with preservation of fairly

good VA due to its initially extrafoveal site.

The intraretinal fluid and cysts resolved slowly in

response to treatment with return of almost normal

morphology after 3 or 4 months (Figure 39).

This improvement persisted for several months, but another recurrence was observed on OCT and an-

However, one month later, the patient experienced a recurrence with no loss of visual acuity but with multiple changes on OCT.

OCT demonstrated accentuation of the PED, a dense hyper-reflective zone anterior to the RPE, disruption of the external limiting membrane, and numerous subfoveal bright hyper-reflective spots at the edge of the recurrent SRF (Figures 39d and 40).

A fifth injection (Macugen*) was therefore performed and was rapidly effective, restoring normal morphology (Figures 39e and 41).

At the last Examination

Fifteen months after the first visit, retinal morphology was almost normal, despite a small amount of subretinal fluid, slight thickening of the IS/OS interface, and several subfoveal alterations of the outer segments with a concomitant decrease of VA to 20/32.

Angiography

Only minor lesions were observed: the area of occult CNV was still visible in the form of several pinpoint leaks with slight diffuse leakage.

On SLO-ICG, the zone of the PED remained dark but had low contrast and was poorly-delineated. The neovascular membrane was barely visible (Figure 39).

giography after 9 months at the monthly follow-up with return of all signs but with no loss of VA. This emphasized the importance of follow-up imaging.

Another IVT injection was again effective, throughout 15 months of follow-up.

This suspension of treatment is probably only tem-

porary. Persistence of the several alterations of the outer retinal layers, bright hyper-reflective spots, and a small SRF indicate the need for long-term follow-up.

a

b

3 rd month

Fluid

After IVT 3

20/25

Hyper-reflective dots

6 th month

d

e

20/32