Multi-imaging distinguishes choroidal neovascularization types

Four imaging techniques identified signs of retinal angiomatous proliferation in patients with AMD.

Using a range of imaging modalities can be effective in identifying the types of choroidal neovascularization lesions in patients with age-related macular degeneration, according to a study.

The cross-sectional retrospective study singled out retinal angiomatous proliferation (RAP), a particularly aggressive lesion type, in a group of AMD patients by using the multi-imaging approach.

At Luigi Sacco Hospital Eye Clinic at the University of Milan, Italy, researchers studied images of one eye in each of 30 patients with neovascular AMD. Each of the subjects was affected by active neovascular lesions, including occult type 1, classic type 2 and RAP type 3. Sixteen of the 30 cases were classified as RAP cases.

Corresponding study author Giovanni Staurenghi, MD, told Ocular Surgery News that the problems associated with choroidal neovascularization vary, from loss of visual acuity to low vision.

“In particular, RAP lesions are quite aggressive and have a high possibility of involving both eyes in a shorter [period of time],” he said.

Lesion characteristics

Using the images, the authors looked for characteristics found more often in RAP lesions than in other types. Fluorescein angiography showed shunting of blood flow to the lesions; indocyanine green angiography detected late leakage; spectral domain OCT showed both intraretinal cysts and retinal pigment epithelium interruption along the retinal pigment epithelium detachment; and infrared light showed pseudodrusen.

Shunting of blood flow to lesions was seen in 56% of eyes with RAP but in none of the other eyes. Late leakage was evident in all RAP cases and in 7% of the others. Intraretinal cysts were found in all RAP cases and in 14% of the others. Retinal pigment epithelium interruption was detected in 93% of RAP cases and 15% of the other types, and reticular pseudodrusen was found in 87% of RAP patients and 21% of the others.

Study limitations noted by the authors included the small sample size and the potential for bias because they used “selective nonconsecutive cases analyzed in a retrospective manner.”

Nonetheless, the authors maintained that multi-imaging helps differentiate lesion types.

“This [multi-imaging] approach has important prognostic implications that could affect therapeutic results. In fact, evaluation of a single sign can make diagnosis difficult and unreliable. This is important in both clinical practice and in multicentered clinical trials,” the authors wrote. “In the clinic, recognizing RAP lesions may lead to a more aggressive follow-up of the patients. In clinical trials, a correct classification of lesion types is mandatory when considering the results and any possible bias.”

Other risks

According to Staurenghi, in cases of “normal” choroidal neovascularization in AMD, there is about a 30% chance that the second eye will become involved in 5 years, whereas in the RAP type, there is about a 50% chance in 3 years.

“Moreover, pseudodrusen is a common sign for geographic atrophy. These patients are also at high risk of developing geographic atrophy not related to the treatment,” Staurenghi said. “In the CATT study and IVAN study, geographic atrophy could be more correlated to the presence of RAP lesions.”

Staurenghi added that choroidal neovascularization may be treated with anti-VEGFs, but when diagnosed early, the chance that it can be controlled with minimal treatment could be high.

Staurenghi said the four multi-imaging modalities used in the study can be performed quickly and efficiently. The Spectralis HRA+OCT (Heidelberg Engineering) was the single device used in the study.

“Everything can be done in the same session with the same instrument in 10 minutes maximum, without asking the patient to move from the instrument,” he said. – by Joe Green

Disclosure: Staurenghi reports no relevant financial disclosures.

Using a range of imaging modalities can be effective in identifying the types of choroidal neovascularization lesions in patients with age-related macular degeneration, according to a study.

The cross-sectional retrospective study singled out retinal angiomatous proliferation (RAP), a particularly aggressive lesion type, in a group of AMD patients by using the multi-imaging approach.

At Luigi Sacco Hospital Eye Clinic at the University of Milan, Italy, researchers studied images of one eye in each of 30 patients with neovascular AMD. Each of the subjects was affected by active neovascular lesions, including occult type 1, classic type 2 and RAP type 3. Sixteen of the 30 cases were classified as RAP cases.

Corresponding study author Giovanni Staurenghi, MD, told Ocular Surgery News that the problems associated with choroidal neovascularization vary, from loss of visual acuity to low vision.

“In particular, RAP lesions are quite aggressive and have a high possibility of involving both eyes in a shorter [period of time],” he said.

Lesion characteristics

Using the images, the authors looked for characteristics found more often in RAP lesions than in other types. Fluorescein angiography showed shunting of blood flow to the lesions; indocyanine green angiography detected late leakage; spectral domain OCT showed both intraretinal cysts and retinal pigment epithelium interruption along the retinal pigment epithelium detachment; and infrared light showed pseudodrusen.

Shunting of blood flow to lesions was seen in 56% of eyes with RAP but in none of the other eyes. Late leakage was evident in all RAP cases and in 7% of the others. Intraretinal cysts were found in all RAP cases and in 14% of the others. Retinal pigment epithelium interruption was detected in 93% of RAP cases and 15% of the other types, and reticular pseudodrusen was found in 87% of RAP patients and 21% of the others.

Study limitations noted by the authors included the small sample size and the potential for bias because they used “selective nonconsecutive cases analyzed in a retrospective manner.”

Nonetheless, the authors maintained that multi-imaging helps differentiate lesion types.

“This [multi-imaging] approach has important prognostic implications that could affect therapeutic results. In fact, evaluation of a single sign can make diagnosis difficult and unreliable. This is important in both clinical practice and in multicentered clinical trials,” the authors wrote. “In the clinic, recognizing RAP lesions may lead to a more aggressive follow-up of the patients. In clinical trials, a correct classification of lesion types is mandatory when considering the results and any possible bias.”

Other risks

According to Staurenghi, in cases of “normal” choroidal neovascularization in AMD, there is about a 30% chance that the second eye will become involved in 5 years, whereas in the RAP type, there is about a 50% chance in 3 years.

“Moreover, pseudodrusen is a common sign for geographic atrophy. These patients are also at high risk of developing geographic atrophy not related to the treatment,” Staurenghi said. “In the CATT study and IVAN study, geographic atrophy could be more correlated to the presence of RAP lesions.”

Staurenghi added that choroidal neovascularization may be treated with anti-VEGFs, but when diagnosed early, the chance that it can be controlled with minimal treatment could be high.

Staurenghi said the four multi-imaging modalities used in the study can be performed quickly and efficiently. The Spectralis HRA+OCT (Heidelberg Engineering) was the single device used in the study.

“Everything can be done in the same session with the same instrument in 10 minutes maximum, without asking the patient to move from the instrument,” he said. – by Joe Green

Disclosure: Staurenghi reports no relevant financial disclosures.