What are the other Names for this Condition? (Also known as/Synonyms)

• RAM (Retinal Arterial Microaneurysm)
• RAMA (Retinal Arterial Microaneurysm)
• Retinal Arterial Microaneurysm (RAM)

What is Acquired Retinal Macroaneurysm? (Definition/Background Information)

• Acquired Retinal Macroaneurysm is a condition involving the retinal arterioles (small diameter blood vessel) that is mostly noted in elderly women with high blood pressure. In majority of cases, only a single aneurysm involving one eye is noted
• In this condition, the retinal blood vessel walls weaken due to factors, such as cardiovascular disease or hypertension, and develops a macroaneurysm (an aneurysm/bulge developing on a small blood vessel)

Who gets Acquired Retinal Macroaneurysm? (Age and Sex Distribution)

• The incidence rate of Acquired Retinal Macroaneurysm is reportedly 1 in 4,500 among the general population
• Individuals of any age category may be affected; however, a vast majority of the cases are reported in older adults
• Both males and females may be affected; a greater number of cases are seen in women. Around 80% of the cases are reported in females
• Worldwide, individuals of all races and ethnicity are prone to developing the condition

What are the Risk Factors for Acquired Retinal Macroaneurysm? (Predisposing Factors)

The main risk factors for Acquired Retinal Macroaneurysm may include:

• Hypertension or high blood pressure, causing chronic venous stasis
• Cardiovascular diseases
• Hyperlipidemia - a group of disorders that result in high levels of fats and cholesterol in the body

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Acquired Retinal Macroaneurysm? (Etiology)

Acquired Retinal Macroaneurysm develops secondary to a condition known as arteriosclerosis, which is a form of atherosclerosis.

• In atherosclerosis, the arteries become hard and clogged, thus weakening the arterial wall. An aneurysm is an abnormal widening or bulge in an artery, caused by a weakening of the arterial wall
• In Acquired Retinal Macroaneurysm, the retinal arteriole is affected resulting in a macroaneurysm. Thus, the condition is also known as Retinal Arterial Macroaneurysm (RAM)

What are the Signs and Symptoms of Acquired Retinal Macroaneurysm?

The signs and symptoms of Acquired Retinal Macroaneurysm may differ from one individual to another. It may be mild or severe, depending on several factors.

• In most cases, the condition develops silently, and the individual is unaware of the condition during the initial stages. In others, a rapid deterioration of vision is noted
• Typically, a solitary macroaneurysm is noted. However, in 10% of the cases, involvement of both the eyes are noted. And, in about 20% cases, more than one aneurysm is seen
• Superotemporal retinal arteriole is the most common site for RAM, followed less commonly by the cilioretinal arteries

Based on the onset and development of Retinal Arterial Macroaneurysm (RAM), the condition is classified as quiescent, hemorrhagic, and exudative.

• Quiescent RAM: This is an incidental finding on imaging studies; the condition does not present any significant symptoms. Most of the cases are known to be asymptomatic and quiescent
• Hemorrhagic RAM: An acute onset of the condition is noted with significant visual symptoms and progressive vision impairment. Internal hemorrhaging of the eye structures is noted
• Exudative RAM: The onset of the condition is slow and gradual. A progression of the condition can result in fluid-filled intraretinal structures that has the potential to result in retinal edema and irreversible central vision loss

Associated signs and symptoms of the underlying condition/disorder may also be observed.

How is Acquired Retinal Macroaneurysm Diagnosed?

Individuals with Acquired Retinal Macroaneurysm may have sudden vision loss in the absence of pain. 

Acquired Retinal Macroaneurysm may be diagnosed by the following observations and tests:

• Physical examination and medical history evaluation
• Assessment of signs and symptoms
• General eye exam
• Lipid profile test
• Fundoscopic (ophthalmoscopic) examination by an eye specialist, who examines the back part of the eye (or the fundus)
• Visual acuity test using a special and standardized test chart (Snellen chart)
• Slit-lamp examination
• Visual evoked potential (VEP) test
• Fundus fluorescein angiography
• Optical coherence tomography (OCT) of eye
• Imaging studies including CT and MRI scans of the head and neck region, if needed

Additional tests and procedures to diagnose the underlying causative condition may be needed.

A differential diagnosis to eliminate other conditions may be considered, before arriving at a definitive diagnosis. These may include:

• Adult-onset Coat’s disease 
• Arteriovenous malformation (AVM)
• Branch retinal vein occlusion
• Capillary hemangioma
• Cavernous hemangioma
• Diabetic retinopathy and diabetic macular edema
• Exudative age-related macular degeneration (ARMD)
• Retinal telangiectasia
• Traumatic multilayer hemorrhage
• von Hippel Lindau syndrome 

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Acquired Retinal Macroaneurysm?

The complications of Acquired Retinal Macroaneurysm may include:

• Severe bleeding in the eye
• Development of epiretinal membrane
• Permanent damage to the retina and retinal structures, including retinal detachment
• Permanent vision loss
• Decreased quality of life
• Treatment related complications

Complications arising from the underlying/associated condition, if any, may be noted.

How is Acquired Retinal Macroaneurysm Treated?

The treatment of Acquired Retinal Macroaneurysm depends on the severity of the condition, the presenting signs and symptoms, the underlying causative factor, and overall health status of the individual. The treatment measures include treating the symptoms and managing the underlying condition/disorder.

• Undertaking suitable treatment for hypertension and cardiovascular diseases, if any, such as through medications and suitable lifestyle modifications
• Laser eye surgery may be recommended based on the healthcare expert’s evaluation, particular in case of macular edema, exudative RAM, and retinal detachment
• Intravitreal anti-VEGF injections
• Pars plana vitrectomy if vitreous hemorrhage is noted
• Close follow-up and periodic visits to the healthcare provider is important

In many individuals, a spontaneous resolution of the condition (involution of the aneurysm or decrease in size) is noted. Hence, the healthcare provider may choose to have a ‘wait and watch’ approach following diagnosis of the condition.

How can Acquired Retinal Macroaneurysm be Prevented?

It may be difficult to prevent some cases of Acquired Retinal Macroaneurysm. However, the following factors may help reduce one’s risk for developing the condition:

• Adopting a healthy lifestyle
• Considering weight loss if one is overweight or obese
• Smoking cessation
• Early and adequate treatment of any heart health issues

What is the Prognosis of Acquired Retinal Macroaneurysm? (Outcomes/Resolutions)

The overall prognosis of Acquired Retinal Macroaneurysm depends on the severity of the condition, the underlying risk factors, and overall health status of the individual.

• Some cases are known to get better spontaneously, and no vision impairment is observed. However, this may take several years
• It is reported that the prognosis is poor when the macula is involved (such as due to macular edema), or if other eye complications are noted
• Sometimes, a favorable prognosis is noted despite internal hemorrhaging (bleeding) within the eye, when it is mild

Additional and Relevant Useful Information for Acquired Retinal Macroaneurysm:

Please visit our Eye & Vision Health Center for more physician-approved health information:

https://www.dovemed.com/health-topics/vision-center/