Question of the day: Which of the following answer choices are true?

Question:

Which of the following answer choices are true?

	1. Cement leaks occur in less than 10% of vertebroplasty procedures.
	2. Pulmonary cement embolization occurs in less than 5% of vertebroplasty procedures.
	3. Pulmonary cement embolization is usually clinically significant.
	4. PMMA appears to cause an inflammatory reaction and subsequent fibrosis.
	5. PMMA is considered inert.

Answer:

The correct answers for the question "Which of the following answer choices are true?" are:

2. Pulmonary cement embolization occurs in less than 5% of vertebroplasty procedures.

5. PMMA is considered inert.

Explanation
1. Cement leaks are common with vertebroplasty [A recent meta-analysis demonstrated that cement leaks occur in 76% of patients who undergo vertebroplasty.]

2. Pulmonary cement embolization occurs during 2.1% of vertebroplasty procedures [Although cement leaks are common (76%), most cement leaks do not cause pulmonary cement embolization. According to a prospective trial involving 532 vertebroplasty procedures, pulmonary cement embolization had an incidence of 2.1%.]

3. Pulmonary cement embolization is usually not clinically significant. [A large prospective trial of 532 vertebroplasty procedures determined that pulmonary PMMA embolism had an incidence of 2.1%, with all of the patients who developed a pulmonary cement embolism remaining asymptomatic.]

4. PMMA does not cause an inflammatory reaction. [However, a follow up of 14 patients with pulmonary cement embolism demonstrated no reactive pulmonary changes after 22 months.]

5. PMMA is considered inert. [The absence of inflammatory change from a PMMA embolus is in keeping with numerous studies which have validated the inert in-vivo nature and biocompatibility characteristics of PMMA].

From the manuscript:
Investigation of polymethylmethacrylate pulmonary embolus in a patient ten years following vertebroplasty
Radiology Case. 2011 Oct; 5(10):14-21

This article belongs to the Interventional section.

From the manuscript

Investigation of polymethylmethacrylate pulmonary embolus in a patient ten years following vertebroplasty

Free full text article: Investigation of polymethylmethacrylate pulmonary embolus in a patient ten years following vertebroplasty

Abstract
Percutaneous vertebroplasty (PV) is a procedure commonly used for the treatment of vertebral compression fractures, and the number of procedures has been steadily increasing over the past decade. We report a case of an 81 year old female with a history of breast cancer that developed two vertebral body compression fractures and was subsequently treated with PV. The patient developed a subsegmental pulmonary polymethylmethacrylate (PMMA) embolus as a complication of the procedure. Ten years following the procedure, she remained asymptomatic with the PMMA embolus being discovered incidentally during workup for a suspected chronic obstructive pulmonary disease (COPD) exacerbation. In reviewing the case, we describe the typical presentation of a pulmonary PMMA embolus and consider methods to decrease the incidence of this complication.

References

1. Gangi A, Kastler BA, Dietemann JL. Percutaneous vertebroplasty guided by a combination of CT and fluoroscopy. ANJR American Journal of Radiology 1994; 15:83-86