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(From left) Adjunct Assistant Professor Troy Puar and Professor Roger Foo at the Clinical Imaging Research Centre (CIRC)

Hypertension is a serious and underestimated silent killer in Singapore and around the world, with one in four adults1 (25 years and above) here diagnosed with the illness. Left untreated, hypertension is a leading risk factor for heart, kidney disease and stroke.

While most patients with hypertension have no underlying curable cause, about 5% of patients may have a potentially curable form called primary aldosteronism, caused by an underlying hormone excess2. Recognising and treating this condition in patients with severe, treatment-resistant hypertension is important, as treatment to cure hypertension is possible for about half of these patients.

A novel imaging technique can identify the source of the hormone excess in patients with primary aldosteronism, according to Professor Roger Foo from the Department of Medicine at the NUS Yong Loo Lin School of Medicine (NUS Medicine) and Senior Consultant Cardiologist at the National University Heart Centre, Singapore; and Adjunct Assistant Professor Troy Puar, Consultant Endocrinologist at Changi General Hospital (CGH). They believe that these findings are pertinent to Singapore and also relevant to patients worldwide.

Working with the Clinical Imaging Research Centre (CIRC) at NUS Medicine, Prof Foo and Adj Asst Prof Puar used a sensitive functional imaging scan to pick up these abnormal glands. This scan, called 11C-Metomidate PET/CT, is able to identify small (<1cm) growths in the gland, and show if the gland is producing too much aldosterone.

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An imaging scan conducted on a patient at CIRC

“Unlike previous techniques that require patients to stay overnight, and undergo an invasive procedure, this scan can be done in less than an hour, without the need for hospitalisation. This imaging technique requires a team with the necessary infrastructure and expertise and the CIRC has enabled Singapore to perform this scan from July 2018,” said Prof Foo.

Currently, patients with primary aldosteronism are identified through adrenal vein sampling (AVS) which is invasive and requires hospitalisation. Hypertension patient, Mr Lim In Chong, who has undergone both AVS and the PET/CT scan said, “The scan is a lot better, simple, non-invasive and quick."

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(From left) Adj Asst Prof Puar, with hypertension patient Mr Lim In Chong, and Prof Roger Foo at CIRC

This new procedure is currently undergoing clinical trials and with this imaging technique, both professors hope that more patients would soon be able to benefit from this scan.

Read the press release here.

WATCH: New Scan to Identify Curable Hypertension

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  1. National Health Survey 2010, Ministry of Health
  2. Loh KC JCEM.2000