How is Exophthalmos measured?

How is Exophthalmos measured?

Proptosis is measured using an exophthalmometer. This device takes a millimeter measurement of the distance between the anterior cornea and the temporal orbital rim for each eye. For an individual patient the measurement base is the distance between the two temporal orbital rim margins.

How is proptosis measured in CT?

Method 1: Proptosis measurements were made on the CT scan by drawing a horizontal line between the lateral orbital rims on the axial plane that bisects the lens and then drawing a perpendicular line forward to the posterior surface of the cornea.

How is proptosis Radiopaedia measured?

The reference line for measurement of proptosis is the interzygomatic line (a line is drawn at the anterior portions of the zygomatic bones): the distance from this line to the posterior sclera is normally 9.9 +/- 1.7 mm. the distance from this line to the anterior surface of the globe should be <23 mm.

What is the normal range of Exophthalmos?

The normal range is 12–21 mm. Upper normal limit for people of African origin is a little higher, about 23–24 mm. A difference greater than 2 mm between the eyes is significant.

Does exophthalmos go away?

Many of the symptoms of thyroid eye disease tend to improve over time, although this can take several years. There’s a chance your eyes will continue to protrude if corrective surgery is not done. Some people with exophthalmos are left with long-term vision problems, such as double vision.

What is the difference between exophthalmos and Proptosis?

Proptosis can describe any organ that is displaced forward, while exophthalmos refers to only the eyes. Proptosis can include any directional forward displacement.

What is the difference between proptosis and Exophthalmos?

How do you know you have proptosis?

Proptosis can be confirmed with exophthalmometry, which measures the distance between the lateral angle of the bony orbit and the cornea; normal values are < 20 mm in whites and < 22 mm in blacks. CT or MRI of the orbits is often useful to confirm the diagnosis and to identify structural causes of unilateral proptosis.

Does Exophthalmos go away?

When is bilateral ocular proptosis compatible with axial CT?

Abnormal protrusion of the globes bilaterally. On axial CT images and at a level of the lens , the distance from the anterior margin of the globe to interzygomatic line should not exceed 21 mm. If this distance exceeds 21 mm, it is compatible with proptosis 2.

What is the difference between proptosis and exophthalmos?

exophthalmos used to refer to severe (>18 mm) proptosis 5. exophthalmos used to refer to endocrine-related proptosis 6. Proptosis can also be used for other viscera (although rarely seen in contemporaneous usage), but exophthalmos only for the eyes. Enophthalmos is the opposite, referring to displacement of the globe posteriorly.

What does enophthalmos mean in terms of Radiology?

Enophthalmos refers to the posterior displacement of the globe in the orbit. It implies that the globe itself is normal and is caused by either one or a combination of 1: Specific causes include 2: It may or may not be associated with hypoglobus. Exophthalmos (or proptosis) is the opposite, displacement of the globe anteriorly. 1.

What are the requirements for an orbital CT scan?

Review of a number of orbital CT scans (GE 8800) revealed that both scanning and measuring techniques must be standardised to obtain consistent results. The following requirements must be met: The plane of the scan must be parallel to the plane passing through the optic nerve head and lens, i.e. 15 degrees cephalad to the orbitmeatal line.

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