Name of the Procedure:

Ophthalmic Ultrasound, Diagnostic; Quantitative A-Scan Only

Summary

An ophthalmic ultrasound using a quantitative A-scan is a diagnostic procedure that measures the structures in the eye. This scan helps in the precise assessment of the eye's interior, particularly the length of the eyeball.

Purpose

The procedure is used to:

• Accurately measure the axial length of the eye
• Assist in diagnosing conditions like cataracts or intraocular tumors
• Aid in planning for cataract surgery by determining the appropriate lens implant size

Indications

The procedure is recommended for patients who:

• Are preparing for cataract surgery
• Have ocular conditions that affect the eye's internal structures
• Require detailed measurements of the eye for diagnosis or treatment planning

Preparation

• No special fasting or medication adjustments are typically required.
• The patient should remove contact lenses prior to the procedure.
• An initial eye examination may be conducted.

Procedure Description

1. The patient reclines comfortably and an ophthalmologist administers numbing eye drops.
2. A small probe is gently placed on the surface of the eye.
3. Ultrasonic waves are sent into the eye and the echoes are measured to determine the internal eye structures’ dimensions.
4. The scan focuses on obtaining the axial length measurement.

Equipment used includes:

• A-scan ultrasound probe
• Ultrasound machine

Anesthesia: Topical anesthetic eye drops are often used to prevent discomfort.

Duration

The procedure typically takes about 10-15 minutes.

Setting

The procedure is usually performed in an outpatient clinic or an ophthalmologist's office.

Personnel

• Ophthalmologist
• Ophthalmic technician or trained assistant

Risks and Complications

Common risks include:

• Mild discomfort or irritation during the procedure
• Rarely, temporary changes in vision or slight corneal abrasions

Benefits

The precise measurements obtained can:

• Improve the outcomes of cataract surgeries by ensuring the correct lens implant is used
• Aid in accurate diagnosis and management of various eye conditions

Recovery

• Patients can resume normal activities immediately after the procedure.
• Follow-up appointments may be scheduled as needed for additional eye care or surgery planning.

Alternatives

Other diagnostic methods:

• Optical Coherence Tomography (OCT)
• B-Scan Ultrasound

These alternatives may provide different types of information about the eye, and their use depends on the specific diagnostic requirements.

Patient Experience

During the procedure, the patient might feel slight pressure from the ultrasound probe but generally experiences minimal discomfort due to the numbing eye drops. After the procedure, it's normal for the eye to feel a bit irritated, but this sensation should resolve quickly.