Precordial Doppler evaluation of simple bone cyst injection

Area of Science:

• Orthopedics
• Radiology
• Critical Care Medicine

Background:

• Solitary bone cysts are treated with marrow or steroid injections.
• Contrast injection is a standard protocol, sometimes revealing rapid venous outflow.
• Rapid outflow carries risks including embolization and acute respiratory distress syndrome.

Purpose of the Study:

• To evaluate the utility of precordial Doppler monitoring in detecting rapid venous outflow during solitary bone cyst injections.
• To assess the potential for embolization and associated physiological effects.

Main Methods:

• A case series of patients undergoing solitary bone cyst injections.
• Monitoring included precordial Doppler, heart rate, end-tidal CO2 (ETCO2), blood pressure, electrocardiogram, and pulse oximetry.
• Level IV evidence based on a case series with a poor reference standard.

Main Results:

• Seven out of seven particulate injections showed rapid venous outflow via precordial Doppler.
• One bone marrow injection led to transient bradycardia and decreased blood pressure.
• One patient experienced a transient decrease in exhaled CO2.

Conclusions:

• Precordial Doppler monitoring is a novel technique for assessing rapid venous outflow during peripheral cyst injections.
• The findings highlight the potential for serious physiologic effects due to embolization.
• This technique may improve understanding of cyst healing failures and inform the use of particulate substances in injections.