One of the few very urgent scans we perform is perfusion only lungs scans on pregnant individuals. Nuclear Medicine allows the patient to receive a relatively low radiation dose in comparison to CTPA which non pregnant patients may receive. The perfusion only scan is non invasive with a simple injection needed and the scan taking a short period of time.

Prior to patients attending Nuclear Medicine, they will already have received a chest x-ray. If this chest x-ray is clear they will then attend NM. If the scan is inconclusive the patient may still undergo a CTPA scan on occasions.

There is a great deal of evidence available online particularly in the EANM guidelines which supports perfusion only imaging in pregnant patients. A lot of this research is dated however, with newer CT scanners having lower radiation doses it may be in future CTPA scans are an option for pregnant individuals if research supports this.

MAG3 studies are frequently performed as a follow up after the patient having a CT scan.

A CT KUB/Abdomen may show a degree of hydronephrosis, and the MAG3 is performed to actually asses the kidney function which a CT scan is unable to demonstrate.

The findings of the CT may be incidental, with the patient receiving the scan for another clinical indication.

Alongside CT scanning, the pateint may have also had a renal ultrasound of abdomen.

MAG3 studies are also performed om paediatric patients. These might be indicated due to prenatal ultrasound scans. A MAG3 can be used to assess the child's renal function once they have been born.

Indirect cystograms can also be carried out on patients to assess for ureteric reflux. This is less invasive than a cystogram performed under fluoroscopy.

The use of MAG3 scans in the assessment of renal function is long established. It is the only imaging modality where function can be assessed.

It is supported by guidelines published by the BNMS and EANM,