Eye and orbit 超声波

定义

眼睛和轨道 超声波 is a test to look at the eye area. It also measures the size and structures of the eye.

选择的名字

Echography - eye orbit; Ultrasound - eye orbit; Ocular ultrasonography; Orbital ultrasonography; Ocular sonography; Orbital sonography

How the Test is Performed

The test is most often done in the ophthalmologist's office or the ophthalmology department of a hospital or clinic.

Your eye is numbed with anesthetic drops. The 超声波 wand (transducer) is placed against the front surface of the eye.

The 超声波 uses high-frequency sound waves that travel through the eye. Reflections (echoes) of the sound waves form a picture of the structure of the eye. The test takes about 15 minutes.

There are two types of scans: A-scan and B-scan.

a片:

• You will most often sit in a chair and place your chin on a chin rest. You will look straight ahead.
• A small probe is placed against the front of your eye.
• The test may also be done with you lying back. With this method, a fluid-filled cup is placed against your eye to do the test.

b线扫描:

• You will be seated and you may be asked to look in many directions. The test is most often done with your eyes closed.
• A gel is placed on the skin of your eyelids. The B-scan probe is gently placed against your eyelids to do the test.

How to Prepare for the Test

No special preparation is needed for this test.

考试的感觉如何

Your eye is numbed, so you should not have any discomfort. You may be asked to look in different directions to improve the 超声波 image or so it can view different areas of your eye.

The gel used with the B-scan may run down your cheek, but you will not feel any discomfort or pain.

Why the Test is Performed

You may need this test if you have 白内障 or other eye problems.

An A-scan 超声波 measures the eye to determine the right power of a lens implant before 白内障手术.

A B-scan is done to look at the inside part of the eye or the space around and behind the eye (orbit) that cannot be seen directly. This may occur when you have 白内障 or other conditions that make it hard for the doctor to see into the back of your eye. The test may help diagnose 视网膜脱离, tumors, or other disorders.

正常的结果

For an A-scan, measurements of the eye are in the normal range.

For a B-scan, the structures of the eye and orbit appear normal.

What Abnormal Results Mean

b线扫描可能显示:

• Bleeding into the clear gel (vitreous) that fills the back of the eye (vitreous hemorrhage)
• 视网膜癌(视网膜母细胞瘤), under the retina, or in other parts of the eye (such as 黑素瘤)
• Damaged tissue or injuries in the bony socket (orbit) that surrounds and protects the eye
• 异物
• Pulling away of the retina from the back of the eye (视网膜脱离)
• 肿胀(炎症)

风险

To avoid scratching the cornea, do not rub the numbed eye until the anesthetic wears off (about 15 minutes). There are no other risks.

参考文献

Campion T, Miszkiel K, Davagnanam I. 轨道. In: Adam A, Dixon AK, Gillard JH, Schaefer-Prokop CM, eds. 格兰杰 & Allison's Diagnostic Radiology. 7日艾德. Philadelphia, PA: Elsevier; 2021:chap 60.

Fisher YL, Bacci T. Contact B-scan ultrasonography. In: Yanoff M, Duker JS, eds. 眼科学. 6日艾德. Philadelphia, PA: Elsevier; 2023:chap 6.3.

Fisher YL, Silverman RH, Ledesma-Gill G, Engelbert M. Diagnostic ophthalmic 超声波. In: Sadda SVR, Sarraf D, Freund KB, et al, eds. 瑞恩的视网膜. 7日艾德. Philadelphia, PA: Elsevier; 2023:chap 10.