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Pulmonary Ventilation/Perfusion (VQ) Scan

Pulmonary ventilation/perfusion scans are the most commonly used nuclear scanning tests when measuring breathing and circulation in the lungs. VQ Scans are often done in two parts: Pulmonary Ventilation (breathing) and Pulmonary Perfusion (circulation).

Pulmonary Ventilation/Perfusion Indications

VQ Scan Preparation

The patient must have a chest X-ray within 24 hours of having the exam. There are no restrictions for the patient prior to a VQ scan.

VQ Scan Procedure

There are two parts to a VQ scan: ventilation and perfusion. For the pulmonary ventilation portion of the scan, the patient will breathe through a mask for approximately five minutes.  Images will be taken of the lungs during this time. These images show the airflow of the lungs. The patient then receives an IV injection of Tc99mMAA and eight images are taken of the lungs at various angles showing the pattern of the blood flow to the lungs. These pictures allow the physician to look for blood clots in the lung. The total time for the exam is approximately forty-five minutes.