CT, MRI & PET Imaging Test: Principles, Purposes, Costs, Pros & Cons

Computed Tomography (CT) scan, Magnetic Resonance Imaging (MRI) scan and Positron Emission Tomography (PET) scan are the special equipment to create cross-sectional images of the body for understanding the conditions and conducting qualitative and quantitative analysis. Each type of scan has its edges and is designed to diagnose different diseases. This article summarises the differences, principles and usages of CT scans, MRIs and PET scans.

When Do You Need Diagnostic Imaging Tests?

CT scans, MRI, and PET scans can detect numerous diseases and injuries, such as muscle disorders, bone fractures, brain tumours, neurologic diseases, cancers, cardiovascular diseases, and stroke.

Do Insurances cover CT Scans, MRIs and PET Scans?

CT Scans, MRIs, and PET Scans are common nowadays, but they can be costly. Under the Voluntary Health Insurance Scheme (VHIS), these diagnostic imaging tests are well covered and subjected to 30% co-insurance with a limit of HK$20,000 per policy year.

Cigna VHIS Flexi Plan (Superior) Provides 100% Coverage for CT, MRI & PET Scans

Do you want to have better protection? Cigna VHIS Flexi Plan (Superior) covers the expenses incurred by various diagnostic imaging tests, including CT scans, MRIs, PET scans, PET-CT combined scans and PET-MRI combined scans. For more information, please click here.

Comparison Between CT Scans, MRIs And PET Scans

	Computed Tomography (CT Scans)	Magnetic Resonance Imaging (MRI Scans)	Positron Emission Tomography (PET Scan)
Principle	CT scan uses x-rays to build cross-sectional images ("slices") of the body. Cross-sections are reconstructed from measurements of attenuation coefficients of x-ray beams in the volume of the object studied.	Our bodies' protons are an excellent substance for MRIs to employ powerful magnets, which produce a strong magnetic field that forces protons in the body to align with that field. When the radiofrequency field is turned off, the MRI sensors can detect the energy released as the protons realign with the magnetic field.	Radioactive substances will be injected into the patient to produce positron emission, which can trace the glucose and abnormal metabolism in a patient's body. The glucose metabolism rate usually is higher than a normal cell. Therefore, they will absorb more radioactive substances and reflect in the imaging result.
Diseases or Injuries	Bone fractures, brain tumours and angiomas etc.	Heart disease, neurologic disease, joint problems and cancer etc.	Cancer, neurologic disease and cardiovascular disease
Advantages	Convenient and safe Painless Clear images produced	Clear images of body soft tissue: internal tissues, nerves and veins of the organs No radiation	Detect the spread of cancer to other parts of the body from the original cancer site
Duration	Scan time: Approx. 10 seconds	Depend on the types of examination and parts of the body to be examined: from 15mins to 1 hour	Full examination: Approx. 3-4 hours Scan time: Approx. 15-20mins
Cost	Low	Average	High

What Are PET-CT Combined Scans/ PET-MR Combined Scans?

Some hospitals (such as Gleneagles Hospital, Baptist Hospital; details below) provide PET-CT combined and PET-MR combined scan services. These two combined scans are more accurate in disease diagnosis, especially cancers, through overlapping two diagnostic images.

Cost of CT Scans, MRIs and PET Scans at Private Hospitals in Hong Kong

The charges of diagnostic imaging tests vary depending on the scanning area and the use of contrast dye. Below are the costs incurred at the general outpatient at six local private hospitals for your references. Fees are listed in Hong Kong Dollars.

Hong Kong Island

1. Gleneagles Hospital Hong Kong: CT, MRI and PET Scan Price List

Items	CT Scans	MRIs
Brain	$4,040	$9,870
Thorax	$6,060	N/A
Upper Abdomen	$6,390	$10,460
Thorax + Abdomen	$11,650	N/A
Joint (One Side)	$5,610	$9,870
Cervical Spine	$7,240	N/A
Thoracic / Lumbar Spine	$7,240	N/A

Items	PET-MR	PET-CT
Whole Body Trunk (Plain) (with one dedicated region contrast MRI)	$18,540	$17,830

2. Hong Kong Sanatorium & Hospital: CT, MRI and PET Scans Price List

Items	CT Scans	MRIs
Brain	$5,450	$13,330
Thorax	$7,740	$14,520
Upper Abdomen	$6,840	$14,520
Thorax + Abdomen	$19,910	N/A
Joint (Single side)	$7,400	$13,520
Cervical / Thoracic / Lumbar Spine	$8,170	$13,520

Items	PET
Brain	$12,820
Whole Body Scanning	$16,870
Regional Scanning	$12,820

Kowloon

1. Hong Kong Baptist Hospital: CT, MRI and PET Scans Price List

Items	CT Scans	MRIs
Brain	$4,080	$9,350
Thorax	$6,270	N/A
Upper Abdomen	$5,840	$10,490
Whole Abdomen	$8,330	$18,800
Thorax + Abdomen	$11,900	N/A
Hypertension Package (Renal Arteries, Adrenals, Kidneys)	$6,790	N/A
Cervical / Thoracic / Lumbar Spine	N/A	$9,350

Items	PET-CR	PET-MR
Whole Body (Contrast)	$18,630	$22,000 – 31,000
Regional	N/A	$12,600 – 22,400

2. St. Teresa's Hospital: CT and MRI Scans Price List

Items	CT Scans	MRI
Brain	$3,500	$9,200
Thorax	$5,400	N/A
Abdomen	$5,400	$9,990
Pelvis	$5,400	$9,990
One Joint	N/A	$9,200

PET Scans are not available in St. Teresa’s Hospital.

New Territories

1. Hong Kong Adventist Hospital – Tsuen Wan: CT and MRI Scans Price List

Items	CT Scans	MRIs
Brain	$2,940	$6,650
Thorax	$4,060	$7,210
Upper Abdomen	$4,060	$7,140
Lower Abdomen	$3,990	$7,140
Whole Abdomen	$6,020	N/A
Thorax + Abdomen	$7,770	N/A
Cervical / Thoracic / Lumbar Spine	$3,640 – $4,550 (depends on different spines)	N/A

Items	PET-CR*
Whole Body Trunk	$12,600
Whole Body Trunk with Brain	$13,300
Whole Body Trunk with Extremities	$13,300
Whole Body Trunk with Brain and Extremities	$14,000

2. Union Hospital: CT, MRI and PET Scans Price List

Items	CT Scans	MRIs
Brain	$3,600	$5,500
Thorax	$5,200	N/A
Abdomen	$5,230	$9,500
Abdomen & Pelvis	$7,950	$17,650
Knee	N/A	$5,500
Cervical / Lumbar Spine	N/A	$5,500

Items	PET-CT (with Contrast)
Whole Body Trunk	$16,800
Whole Body Trunk with Brain	$18,400

FAQs About CT Scans, MRIs and PET Scans

1. How severe is the CT scan radiation?

Using ionised radiation, CT scans expose you to more radiation than typical X-rays. Research shows that receiving one CT scan equals the amount of exposure to natural radiation for several years.

CT Scans Procedure	Time of Exposure to Natural Radiation
Spine	6 months
Head	8 months
Chest	2 years
Abdomen and Pelvis	3 years
PET-CT	8 years

Natural radiation exists everywhere in our daily life and nature. From a medical point of view, CT scans produce clear images for accurate diagnoses. Their advantages outweigh the disadvantages. If you have any concerns before having a CT scan, please consult your doctors and clearly understand the details of the scans:

• Are CT scans necessary?
• What is the dosage of contrast materials used for the scan?
• Are repeated CT scans necessary?

2. Who Should Not Receive CT Scans?

The groups below should not receive CT scans:

• The pregnant
• Those allergic to medications, contrast dye, iodine and shellfish should inform their doctor
• Those with kidney failures or other kidney problems, since contrast materials may lead to kidney failure under certain circumstances

3. How to Choose Between CT Scans and MRIs?

While PET scans trace the abnormalities of the body’s cells, the functions of CT scans and MRIs are relatively similar. In general, your doctor recommends specific diagnostic imaging tests regarding your conditions. For detailed images of soft tissues, ligaments or organs, your doctor may suggest performing MRIs. Conditions include:

• Herniated disc
• Ligament rupture
• Soft tissue disorder

CT scans are recommended for those with bone fracture, head injury or in need of general organ scanning.

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CT scans, MRIs, and PET scans are common diagnostic imaging tests for effectively detecting early-stage cancers or other critical illnesses. Despite high costs, the tests are essentials when needed. Cigna VHIS Flexi Plan(Superior) offers full compensation for diagnostic imaging tests and a lifetime benefit limit up to HK$ 20,000,000. Please click here for more details.

Sources:

1. CT Scan vs. MRI
2. Patient Safety - Radiation Dose in X-Ray and CT Exams
3. 科學人雜誌
4. Risks of Computed Tomography (CT) Scan