Diagnostic Imaging at The Health Equation

Diagnostic imaging can provide valuable information when a patient’s history and clinical examination indicate that further investigation is required.

At The Health Equation, imaging is not requested routinely or simply to “look for something.” An investigation is recommended when its findings are reasonably likely to:

• Clarify a diagnosis
• Confirm or exclude clinically important pathology
• Influence treatment or rehabilitation
• Guide referral to a medical specialist
• Help determine whether further investigation is required

Available investigations include X-ray, MRI, ultrasound, CT and DXA bone-density scanning. The most appropriate form of imaging is selected according to the clinical question, taking account of its likely benefits, limitations, safety and cost.

Imaging findings are interpreted alongside the patient’s history and clinical examination rather than being considered in isolation.

When May Diagnostic Imaging Be Helpful?

Imaging may be considered when symptoms, examination findings or the clinical history suggest that visualising internal structures could materially assist diagnosis or management.

Examples include:

• Significant trauma or suspected fracture
• Persistent or progressive pain that has not responded as expected
• Neurological symptoms such as weakness, altered sensation or loss of coordination
• Suspected joint, tendon, ligament or muscle injury
• Possible inflammatory, infective or malignant disease
• Unexplained swelling or a palpable mass
• Assessment of internal organs or vascular structures
• Evaluation of bone density and fracture risk
• Further investigation of an abnormal clinical or laboratory finding
• Planning specialist referral, injection or surgical opinion

The presence of pain alone does not necessarily mean that imaging is required. Many common age-related findings are also present in people without symptoms. The decision to request imaging therefore depends upon whether the result is likely to change the patient’s clinical management.

Choosing the Appropriate Investigation

Different forms of imaging answer different clinical questions. The choice depends upon the structures being assessed, the suspected diagnosis and whether exposure to ionising radiation is justified.

• X-ray: primarily used for fractures, joint alignment, arthritis and other changes affecting bone
• MRI: provides detailed assessment of soft tissues, intervertebral discs, nerves, joints, bone marrow and many internal structures
• Ultrasound: useful for selected tendons, muscles, joints, abdominal and pelvic organs, and vascular assessment
• CT: produces detailed cross-sectional images and is particularly useful for bone, lungs, internal organs and selected cardiovascular investigations
• DXA: measures bone-mineral density and supports assessment of osteoporosis and fracture risk

Sometimes more than one investigation may be appropriate, but the least invasive and most clinically useful option should generally be selected first.

X-ray

X-rays use a small amount of ionising radiation and are particularly useful for assessing:

• Suspected fractures or dislocations
• Joint alignment and instability
• Osteoarthritis and other degenerative changes
• Certain inflammatory joint conditions
• Bone lesions or structural abnormalities
• Chest and lung conditions where clinically indicated

X-rays provide good definition of bone but much less information about muscles, tendons, discs, nerves and other soft tissues.

Because they involve ionising radiation, X-rays should only be requested when clinically justified. Routine spinal X-rays are generally not appropriate for uncomplicated back or neck pain unless the history or examination suggests fracture, significant pathology, deformity or another finding likely to alter management.

Patients should inform the referrer and imaging centre if they are pregnant or could potentially be pregnant.

MRI – Magnetic Resonance Imaging

MRI uses a powerful magnetic field and radiofrequency energy to produce detailed cross-sectional images without ionising radiation.

It is particularly useful for assessing:

• Intervertebral discs, spinal nerves and the spinal cord
• Brain and neurological structures
• Ligaments, tendons, muscles and cartilage
• Joints and surrounding soft tissues
• Bone marrow and occult bone injury
• Inflammatory, infective or malignant processes
• Selected internal organs and blood vessels

MRI can provide considerable anatomical detail, but abnormal findings do not always explain a patient’s symptoms. Disc degeneration, disc protrusions, osteoarthritis and tendon changes are commonly found in people without pain. Results must therefore be correlated carefully with the history and clinical examination.

An MRI examination commonly takes between 20 and 45 minutes, although more complex studies may take longer. Patients need to remain relatively still, and the enclosed scanner can be challenging for people with claustrophobia. Open or wider-bore scanners, reassurance or appropriate sedation may be considered when necessary.

MRI Safety and Patient Screening

MRI does not use ionising radiation, but it produces a powerful magnetic field. Every patient must therefore complete detailed safety screening before entering the scanner.

Particular consideration is required for patients with:

• A pacemaker, implantable cardioverter-defibrillator or other cardiac device
• Cochlear implants, neurostimulators, infusion pumps or other implanted electronic devices
• A history of metal fragments in the eye, particularly following grinding, welding or metalwork
• Surgical clips, plates, screws, pins or other implanted metal
• Joint replacements, including total hip or knee replacements
• Previous brain, spinal, cardiac or vascular surgery
• Retained shrapnel, bullets or other metallic foreign bodies
• Pregnancy or possible pregnancy
• Severe claustrophobia or difficulty lying still

Having a pacemaker or metallic implant does not automatically prevent MRI. Many modern devices and joint replacements are MR Conditional, meaning that scanning may be possible under defined conditions. The imaging centre must know the precise make, model and date of implantation wherever possible. Joint replacements may also produce image distortion or artefact close to the implant.

A patient with a possible metallic foreign body in the eye may require an X-ray or review of previous imaging before MRI can safely proceed.

MRI Contrast and Kidney Function

Some MRI examinations require an intravenous gadolinium-based contrast agent to improve visualisation of particular tissues, blood vessels or areas of suspected pathology. Contrast is not required for every MRI and should be used only when it is likely to provide additional clinically useful information.

Before contrast is administered, the imaging centre may require a recent blood test measuring kidney function, particularly the estimated glomerular filtration rate (eGFR). This is especially important for patients with known kidney disease, reduced renal function, previous kidney surgery or transplantation, diabetes, or other relevant risk factors.

Patients should also disclose any previous reaction to MRI contrast, significant allergies and whether they may be pregnant. The radiology team makes the final decision about whether contrast can be administered safely and whether any additional precautions are required. MHRA MRI safety guidance supports detailed screening for implanted devices and metallic foreign bodies, while UCLH guidance confirms that renal function/eGFR may be required when contrast is planned.

Ultrasound

Ultrasound uses high-frequency sound waves to create real-time images and does not involve ionising radiation.

Depending on the clinical question, it may be used to assess:

• Tendons, muscles, bursae and selected ligaments
• Joint swelling, inflammation and fluid collections
• Soft-tissue lumps or masses
• Abdominal and pelvic organs
• The thyroid and other superficial structures
• Blood vessels using Doppler ultrasound
• Image-guided injections or other procedures

Ultrasound allows structures to be examined dynamically while the patient moves, which can be particularly helpful for selected musculoskeletal problems.

Its usefulness depends upon the structure being examined, the patient’s anatomy and the experience of the practitioner performing the scan. Some deep structures, intra-articular tissues and areas obscured by bone or gas cannot be assessed adequately with ultrasound and may require MRI, CT or another investigation.

CT – Computed Tomography

CT uses X-rays and computer processing to produce detailed cross-sectional images of the body. It is much faster than MRI and is particularly useful for assessing:

• Complex fractures and detailed bone anatomy
• The lungs and chest
• Abdominal and pelvic organs
• Kidney stones
• Acute trauma
• Selected blood-vessel and cardiovascular conditions
• Areas where MRI is unsuitable or unavailable

CT involves more ionising radiation than a conventional X-ray, although the dose varies considerably according to the body area and scanning protocol. It should therefore be requested only when the expected clinical benefit justifies the exposure.

Some CT examinations require an iodine-based contrast agent. Patients may need assessment of kidney function, including a recent eGFR, and should disclose kidney disease, diabetes, relevant medication, thyroid disease, allergies or any previous contrast reaction.

Coronary Artery Calcium Scoring

A coronary artery calcium score is a specialised, low-dose CT scan that measures calcified plaque within the coronary arteries. It may provide additional information about cardiovascular risk when conventional risk assessment leaves uncertainty about the need for preventive treatment.

It is not a complete examination of the heart, does not detect all forms of coronary plaque and is not appropriate for every patient. The result should be interpreted alongside symptoms, family history, blood pressure, cholesterol, smoking history, diabetes risk and established tools such as QRISK3. Patients with possible cardiac symptoms may require a different or more urgent form of assessment.

DXA Bone-Density Scanning

Dual-energy X-ray absorptiometry—usually abbreviated to DXA—uses a very low dose of ionising radiation to measure bone-mineral density, most commonly at the hip and lumbar spine.

DXA may be appropriate for patients with:

• Suspected osteoporosis or osteopenia
• A previous low-trauma or fragility fracture
• Early menopause or other hormonal risk factors
• Prolonged corticosteroid use
• Low body weight or significant loss of height
• Conditions or medication associated with reduced bone density
• A strong family history of osteoporosis or hip fracture
• An elevated fracture risk identified using tools such as FRAX®

Results are reported using T-scores and Z-scores. A T-score compares your bone mineral density with that of a healthy young adult at peak bone mass. In postmenopausal women and men aged 50 years or over, the usual diagnostic thresholds are:

• –1.0 or above: bone density within the normal range
• Between –1.0 and –2.5: low bone density, often termed osteopenia
• –2.5 or below: osteoporosis

A Z-score compares your bone density with that expected for someone of a similar age, sex and ethnicity. It is particularly useful in children, premenopausal women and men under 50. A Z-score of –2.0 or below is described as “below the expected range for age” and may indicate that further investigation for an underlying cause is appropriate. In these groups, osteoporosis should not usually be diagnosed from bone density alone.

Bone density is only one component of fracture risk. The findings should therefore be considered alongside age, previous fragility fractures, family history, medical conditions, medication, nutrition, muscle strength, balance and falls risk. Tools such as FRAX® may also be used to estimate the probability of a major osteoporotic or hip fracture and help guide management.

DXA scanning is quick and painless. The radiation exposure is very low, but the investigation should still be clinically justified. Repeat scanning is usually undertaken only after an appropriate interval when the result is likely to influence management.

Benefits, Limitations and Incidental Findings

Diagnostic imaging can clarify pathology, support referral and guide management, but no scan provides a complete explanation of a patient’s health.

Important limitations include:

• Structural findings may not correspond with the patient’s symptoms
• Age-related changes are common in people without pain
• A normal scan does not exclude every possible cause of symptoms
• Different investigations vary in their sensitivity and specificity
• Image quality may be affected by movement, body composition or metal artefact
• Some findings remain uncertain and require further investigation

Imaging may also identify an incidental finding—an unexpected abnormality unrelated to the reason the scan was requested. Many incidental findings are harmless and would never cause symptoms or affect health. Nevertheless, once identified, they may lead to surveillance, repeat imaging, specialist referral or occasionally biopsy or another invasive investigation. This can create anxiety, cost and medical intervention without necessarily providing a meaningful health benefit.

For this reason, The Health Equation does not routinely recommend whole-body scans for people without a specific clinical indication, an approach shared by many of our private medical and radiology colleagues. Although whole-body MRI does not involve ionising radiation, it can still reveal uncertain or clinically insignificant abnormalities that are difficult simply to disregard. Whole-body CT carries the additional consideration of radiation exposure.

We favour clinically targeted imaging: selecting the most appropriate examination and anatomical area after considering the patient’s symptoms, history and examination findings. This improves the likelihood that the scan will answer a meaningful clinical question while reducing unnecessary investigation. There may be circumstances in which broader imaging is medically justified, but this should follow careful individual assessment and shared decision-making.

Before requesting imaging, consideration is therefore given not only to what the scan might reveal, but also to whether the result is likely to change management and how any unexpected findings would be handled. This helps reduce unnecessary testing, anxiety and the possibility of an avoidable diagnostic cascade.

Referral, Reporting and Follow-up

When diagnostic imaging is clinically indicated, Gerry prepares an appropriate referral setting out the relevant history, examination findings and the specific clinical question to be addressed.

Imaging is usually arranged through Oryon Imaging in Wimpole Street, London, although other suitable imaging centres may be used according to the investigation required, the patient’s location and clinical circumstances.

The investigation is performed by the imaging provider and interpreted by a consultant radiologist. The radiology report is sent to The Health Equation, where it is reviewed by Gerry. Once Gerry has completed his review, the radiology report is sent directly to the patient, usually within two working days of the investigation.

The radiology report is accompanied by a separate follow-up report from Gerry, helping the patient understand:

• The clinical significance of the imaging findings
• Whether the findings correspond with their symptoms and examination
• Any implications for treatment or rehabilitation
• Whether further investigation or specialist referral is recommended
• The appropriate next steps in management

Where appropriate, Gerry also reviews the images themselves rather than relying solely upon the written radiology report.

The Health Equation makes an administration and clinical review charge of £65, which covers:

• Preparing and submitting the imaging referral
• Reviewing the consultant radiologist’s report
• Reviewing the images where appropriate
• Producing Gerry’s follow-up report for the patient

The cost of the imaging itself is paid directly to the imaging provider. With the patient’s consent, the reports can also be shared with their GP or relevant medical specialist.

Imaging Safety and Shared Decision-making

The decision to request imaging is made collaboratively, considering:

• The clinical question the investigation is intended to answer
• Whether the result is likely to influence management
• The benefits and limitations of the proposed investigation
• Exposure to ionising radiation where relevant
• The possible use of contrast
• Alternative investigations or continued clinical observation
• Cost and patient preference
• The possibility of incidental findings

Gerry holds IR(ME)R certification relating to the safe and appropriate referral of patients for imaging involving ionising radiation. Each referral must be clinically justified and provide the imaging centre with sufficient information to determine the most appropriate examination.

For X-ray and CT investigations, the imaging provider remains responsible for formally justifying and optimising the radiation exposure under its own governance procedures. MRI and ultrasound do not use ionising radiation but have their own safety considerations and limitations.

Patients are encouraged to ask questions and participate in deciding whether imaging is the most appropriate next step. Where the potential risks outweigh the likely clinical value, imaging will not be recommended.

Arranging Diagnostic Imaging

Diagnostic imaging is normally arranged following a clinical assessment so that the referral is based upon an appropriate history, examination and clearly defined clinical question.

New patients should begin with a New Patient Diagnostic Consultation. Existing patients with a new problem or a significant change in symptoms may require an Extended Follow-up Consultation before imaging is requested.