Archives of Academic Emergency Medicine. 2019; 7 (1): e54

LE T T E R TO ED I TO R

A Polyvinyl Chloride Eraser as a Surface Marker for Com-
puted Tomography in Emergency Imaging; a Letter to Edi-
tor
Yuya Murakami1, Taihei Yamada1, Hiromichi Naito1∗

1. Department of Emergency, Critical Care and Disaster Medicine, Okayama University Hospital, Okayama, Japan.

Received: July 2019; Accepted: August 2019; Published online: 28 September 2019

Cite this article as: Murakami Y, Yamada T, Naito H. A Polyvinyl Chloride Eraser as a Surface Marker for Computed Tomography in Emer-

gency Imaging; a Letter to Editor. Arch Acad Emerg Med. 2019; 7(1): e54.

Dear Editor,

In the wake of recent progress in computed tomography (CT)

enabling to obtain high quality images within five minutes,

CT scan has been widely used in emergency diagnostic radi-

ology and is considered best suited for detection of patholo-

gies, as well as assessing the location and extent of lesions in

the emergency department.

Emergency physicians often require confirmation of surface

bruises or wounds coexisting with pathology on CT scan. Al-

ternatively, they may want to confirm the presence or ab-

sence of pathology in the painful lesion. The use of an ap-

propriate surface marker on the skin surface of the painful

lesion may enable them to identify areas of interest and safely

reduce radiation exposure.

CT skin markers detected as virtually artifact-free and

opaque, particularly for mammography, have been commer-

cially available from several healthcare companies, but these

markers are expensive ($57-$86 USD) and may not be easily

accessible. Most metal objects cause artifacts through mul-

tiple mechanisms, including beam hardening, scatter, and

Poisson noise, although some can be reduced using iterative

reconstruction or by combining data from multiple scans (1).

We found that a polyvinyl chloride eraser may be the best sur-

face marker for CT marking applications. As shown in Figure

1, a polyvinyl chloride eraser is visualized as a high-density,

artifact-free homogenous object on CT scan and can be used

as a skin surface marker in the emergency setting. Interest-

ingly, an eraser impacted in the nose of a five-year-old girl

was reported to be identified as a calcified nodular mass by

∗Corresponding Author: Hiromichi Naito; Emergency Department, Crit-
ical Care and Disaster Medicine, Okayama University Graduate School of
Medicine Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku,
Okayama-shi, Okayama, 700-8558, Japan. Email: qq-nakao@okayama-u.ac.jp,
naito05084@gmail.com, Tel: +81-86-235-7426, FAX: +81-86-235-7427.

Figure 1: Computed tomography scan of the chest revealed corre-

spondence of rib fracture (arrowhead) and pain location, marked

with an eraser (arrow).

CT, which was diagnosed as rhinoliths. Thus, an eraser is de-

tected as a high-density and opaque object without artifacts

(2, 3).

In conclusion, a polyvinyl chloride eraser, inexpensive and

easily available in the stationery section of retail stores,

even in developing countries, can serve as a suitable surface

marker for CT examination in an emergency setting to local-

ize pathology from the skin surface. This study protocol was

approved by ethical committee of Okayama University Hos-

pital.

1. Appendix

1.1. Acknowledgements

The staff members of Department of Emergency, Critical

Care and Disaster Medicine, Okayama University Hospital

This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0).
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Y. Murakami et al. 2

are thanked for their cooperation in performance of this

study.

1.2. Author’s contribution

YM and TH performed the procedure. HN wrote the

manuscript and edited the manuscript. All authors read and

approved the final manuscript.

Authors ORCIDs
Hiromichi Naito: 0000-0002-7308-1716

Taihei Yamada: 0000-0001-7575-0365

1.3. Conflict of interest

The authors declare that they have no competing interests.

1.4. Funding and support

None.

References

1. Wellenberg RHH, Hakvoort ET, Slump CH, Boomsma MF,

Maas M, Streekstra GJ. Metal artifact reduction techniques

in musculoskeletal CT-imaging. Eur J Radiol. 2018;107:60-

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2. Munoz A, Pedrosa I, Villafruela M. "Eraseroma" as a cause

of rhinolith: CT and MRI in a child. Neuroradiology.

1997;39(11):824-6.

3. Mukherji SK, Castillo M, Sarangi S, Jacoway J. "Eraseroma"

in a nasal cavity. AJR Am J Roentgenol. 1996;166(3):727.

This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0).
Downloaded from: http://journals.sbmu.ac.ir/aaem


	Appendix
	References