Diagnostic and Interventional Radiology

01Purpose and scope

• This manual supports the course Diagnostic and Interventional Radiology. It describes how imaging departments choose, perform, and report examinations, and how image-guided procedures such as biopsies, drainages, vascular access, and embolizations are planned and carried out in daily practice.
• The diagnostic side covers radiography, fluoroscopy, computed tomography, magnetic resonance imaging, ultrasound, and mammography. The interventional side covers procedures where a radiologist uses real-time imaging to guide a needle, catheter, or device through the body. Nuclear medicine and radiation therapy are adjacent specialties and are touched on only where they affect shared workflow.
• This manual is a working reference. It does not replace formal residency or fellowship training, hospital credentialing, supervision by a qualified radiologist, local protocols, or the equipment manufacturer's instructions. Radiation and procedural rules vary by jurisdiction and by accrediting body, so confirm current requirements with your state or national radiation control authority, your facility's radiation safety officer, and the current published standards from professional societies such as the American College of Radiology.
• Radiology sits inside a larger care pathway. Most decisions start with a referring clinician's question, and most outcomes depend on whether the right study was done, at the right dose, for the right patient, and reported in a way that the next clinician can act on.

02Core principles

• The first principle is justification. Every exam should answer a specific clinical question. Before ordering or performing a study, the team asks what result would change management. If the answer is unclear, the request goes back to the referrer for clarification. Appropriateness tools such as the ACR Appropriateness Criteria help structure this conversation, but they inform rather than dictate the decision.
• The second principle is optimization of radiation dose. Ionizing radiation carries a small cumulative risk, so exposure should be as low as reasonably achievable while still producing a diagnostic image. In practice this means matching protocols to the patient's size and the clinical question, avoiding repeat acquisitions, and using dose-reduction features on modern scanners. Protocol defaults are a starting point, not a final answer.
• The third principle is least invasive effective care. An ultrasound-guided biopsy is often preferred over a surgical biopsy, and a non-contrast study may answer a question that would otherwise need contrast. Each step up in invasiveness should be justified by what it adds.
• The fourth principle is patient-centered communication. Patients need a clear explanation of what the test or procedure involves, what they will feel, what the risks are in plain language, and what happens afterward. Consent is a conversation with a documented outcome, not a signature collected at the table.
• The fifth principle is verification. Patient identity, laterality, procedure type, and allergy status are confirmed by more than one method. Image labels, orders, and the patient's own account should agree before anything invasive begins.

03Planning and preparation

• Planning starts when the request arrives. The reviewer checks the indication, the requested body part, prior imaging available for comparison, and whether the study is consistent with appropriateness guidance. For procedures, the reviewer also checks whether the referring team has documented the reason for intervention and whether the patient has been seen recently enough to judge current status.
• Medication and laboratory review is central for procedures. Anticoagulant and antiplatelet agents must be identified, and the plan for holding or continuing them should follow the proceduralist's protocol, which often draws on published society guidance and the prescribing clinician's input. Laboratory values such as platelet count, international normalized ratio, and hemoglobin are reviewed against the procedure's bleeding risk. Kidney function is reviewed before iodinated contrast, and diabetic medication plans are confirmed with the patient when fasting is required.
• Allergy history needs specific detail. A reported contrast reaction should be characterized by type, severity, and treatment given, because that information shapes premedication decisions and whether an alternative agent is preferred. Latex allergy, anesthesia history, and claustrophobia are also recorded.
• Pregnancy status is confirmed for any patient of reproductive potential using facility policy, which typically combines a direct question with a documented screening step before radiation exposure. Pediatric patients need weight-based planning, appropriate immobilization or sedation planning, and a caregiver present for consent.
• Sedation planning depends on the procedure length, the patient's airway and comorbidities, and the local model of care. Some facilities use nurse-administered moderate sedation, while others involve anesthesia for longer or higher-risk cases. The plan names who is responsible for monitoring and what rescue equipment is in the room.
• Equipment and room preparation are part of planning. Sterile supplies, imaging system checks, emergency medications, a crash cart, and a working suction and oxygen supply should be confirmed before the patient arrives. Contrast agents are checked for expiration and correct labeling.

04Recommended workflow

1. 1
   : Accept and triage the request. Confirm the referring clinician, the clinical question, and urgency. Route incomplete or unclear requests back to the referrer rather than guessing. Flag any request that needs radiologist review before scheduling.
2. 2
   : Review appropriateness and safety data. Check the indication against the applicable appropriateness guidance, pull prior studies, and review renal function, anticoagulation status, allergies, and pregnancy screening where relevant. Record any decision to modify or cancel the request along with the reason.
3. 3
   : Schedule and prepare the patient. Give written and verbal instructions on fasting, medication timing, hydration, and what to bring. Confirm transportation and a responsible adult for sedated procedures. Make sure the interpreter or language support needs are met before arrival.
4. 4
   : Confirm identity and consent on arrival. Use two patient identifiers, confirm the planned exam or procedure, and check the consent form against what is being done. For procedures, the proceduralist or a qualified delegate completes the consent discussion and records it.
5. 5
   : Select and optimize the protocol. Choose the technique and protocol that answers the question with the lowest reasonable dose. For CT, consider automatic exposure control, appropriate scan range, and iterative or deep-learning reconstruction if the scanner offers it and your facility has validated it. For fluoroscopy, use pulsed mode, collimation, and minimal magnification where possible.
6. 6
   : Perform the examination or procedure. For diagnostic studies, the technologist acquires images to the protocol and checks each series for artifacts, positioning, and coverage before the patient leaves. For interventional cases, the team completes a time-out that confirms patient, procedure, site, laterality, allergies, antibiotic timing, and equipment availability. Sterile technique is maintained, and imaging guidance is used to confirm needle or catheter position at each stage.
7. 7
   : Monitor and recover. Vital signs, sedation depth, and bleeding or access-site status are checked at intervals set by the procedure protocol. Discharge criteria and post-procedure instructions are given in writing. Patients who have had contrast are advised on hydration and on signs of delayed reaction.
8. 8
   : Interpret, report, and communicate. The radiologist reviews the images, produces a structured report with findings, comparison, and an impression that answers the clinical question, and communicates critical or unexpected results directly to the responsible clinician with the time and recipient documented. Dose information is recorded in the report or in the radiology information system.

05Quality checks, risk controls and compliance

• Quality control for imaging equipment is required by regulation for many modalities. In the United States, the Mammography Quality Standards Act governs mammography facilities, and the Food and Drug Administration sets performance standards for radiation-emitting products. State agencies usually license facilities and may impose additional rules on staff qualifications, shielding, and dose records. Requirements differ by country and by state, so the authoritative current text should always be checked directly.
• Routine physics testing and acceptance testing after installation or major repair are performed by qualified medical physicists or service personnel according to the facility's quality program. Results are documented, and failures are acted upon before further clinical use. Many departments track image quality and dose indicators over time so that drift is caught early.
• Contrast media carry specific risks. The ACR Manual on Contrast Media is a widely used reference for reaction management, premedication considerations, and renal risk assessment. Facilities should keep reaction kits and emergency drugs current and train staff in their use. Gadolinium-based agents require attention to renal function and to the specific product's labeling.
• Sedation and procedural safety should follow a written policy that defines monitoring standards, the level of staff present, and escalation pathways. Incident reporting systems should capture retained device events, wrong-site concerns, medication errors, and unplanned transfers. These events are reviewed in a non-punitive way to find system causes.
• Peer review is a quality control that many departments use to check interpretive accuracy. The ACR RADPEER framework is one structured method in which a sample of reports is scored for agreement with a later review. Results are used for education and feedback rather than only for discipline.
• Credentialing and privileging define who may perform each procedure. Staff need documented training, supervised experience, and ongoing competence assessment. Scope of practice rules vary by jurisdiction and by the institution's bylaws, so local policy governs.
• Guidance in this manual does not replace qualified professional judgment, approved procedures, or required authorization. Radiology and interventional procedures carry clinical, legal, and regulatory obligations. Decisions about a specific patient belong to the responsible physician, and decisions about a facility's rules belong to its governing body and licensing authority.

06Collaboration and documentation

• Radiology works with many partners. Referring clinicians define the question. Technologists or radiographers acquire images and manage patient safety during scans. Nurses prepare and monitor patients for procedures. Medical physicists manage dose and equipment quality. Anesthesia teams support sedation. Schedulers, pharmacists, and interpreters all affect whether a study happens safely and on time.
• Communication between these roles is most reliable when it is structured. A brief pre-procedure huddle that names the patient, the plan, the access route, the anticoagulation plan, and any concerns takes only a few minutes and catches many problems. Handoffs at the end of a case should include what was done, any complications, and the follow-up expected.
• Documentation serves clinical care, legal record-keeping, and billing, and it should be accurate in all three roles. A procedure note typically records the indication, consent, sedation, technique, equipment and contrast used, findings, specimens sent, complications, and the plan. Dose data, including dose length product or air kerma values where the scanner records them, should be retained according to local retention policy.
• Report wording deserves care. The impression should state the most important conclusion first and make the recommended next step explicit when one is needed. Uncertain findings should be described with appropriate language and with a specific recommendation, such as a follow-up interval or a referral. Recommendations that depend on local resources should name the resource category rather than a specific clinic unless the referrer has agreed to it.
• Patient-facing documentation includes written instructions, consent forms, and discharge information. Plain language matters here. Interpreter use and the method used to confirm understanding should be recorded.

07Measures and continuous improvement

• Useful measures are tied to decisions the department can actually make. Common indicators include the proportion of orders that meet appropriateness guidance, repeat or unplanned repeat examination rates, turnaround time for urgent studies, dose index trends by protocol and body region, discrepancy rates from peer review, procedural complication rates, and incident report volume by type.
• Each measure needs a clear definition, a named data source, and an owner. Without those, numbers drift and become hard to compare. Sampling methods for peer review and for complication tracking should be described in writing so that changes over time can be interpreted correctly.
• Targets should be set locally with leadership and clinical staff. Published benchmarks exist for some measures, but they vary with case mix, population, and equipment, so a facility should not adopt a figure from another setting without checking that it fits. Trend lines usually teach more than single values.
• Improvement work follows a plan, do, study, act cycle or a similar structured method. A typical example is reducing repeat chest radiograph rates by revising the order set and adding a technologist check at acquisition, then measuring the repeat rate again over a defined period. Changes that affect dose or safety should be validated before wide use.
• Feedback to individuals should be specific and private. Technologists who see their own dose or image-quality outliers, and radiologists who see their own peer review results, are more likely to adjust practice when the feedback is framed as learning.

08Common mistakes and how to prevent them

• Wrong-site or wrong-patient errors are among the most serious events in this field. Prevention depends on two identifiers, a time-out before invasive procedures, laterality marking, and a rule that staff stop and verify whenever something looks inconsistent. Image labels and orders should be checked against each other, not assumed to match.
• Protocol creep is a common source of unnecessary dose. A protocol copied from a higher-dose indication, or a default left unchanged for a small patient, can expose people to more radiation than the question requires. Regular protocol review by the radiologist and physicist, along with patient-size-based settings, reduces this risk.
• Incomplete anticoagulation review leads to bleeding, and sometimes to a canceled procedure on the day. Checking medications at the scheduling stage and again at check-in gives two chances to catch changes. The patient should be asked directly, not only through the chart.
• Unrecognized contrast reactions can progress quickly. Staff should know the early signs, have emergency drugs immediately available, and rehearse the response. Patients with a prior reaction may need a documented premedication plan, and the reasoning should be recorded.
• Vague report impressions lead to follow-up failures. An impression that lists findings without a clear conclusion or next step leaves the referrer to interpret the report alone. Structured templates help, but the radiologist still needs to state what matters most.
• Missed incidental findings can create liability and harm. A facility should define a policy for incidental findings, including how they are recorded, communicated, and tracked to a follow-up decision. The responsible clinician is named in the report where the policy requires it.
• Pregnancy screening skipped under time pressure is preventable with a checklist item that cannot be bypassed without a documented reason.

09Practical checklist

• Confirm the clinical question and the urgency before scheduling any study.
• Check the indication against the applicable appropriateness guidance and document the outcome.
• Review prior imaging for comparison and note whether it is available for the reader.
• Verify renal function before iodinated or gadolinium-based contrast when indicated by policy.
• Record contrast allergy details, including reaction type, severity, and treatment.
• Confirm anticoagulant and antiplatelet status and the plan for each agent with the proceduralist.
• Complete pregnancy screening for patients of reproductive potential according to facility policy.
• Use two patient identifiers at check-in and again at the start of the procedure.
• Confirm consent matches the planned procedure and that the discussion is documented.
• Select the protocol for the patient's size and the clinical question, and review dose indicators after the exam.
• Hold a time-out for every invasive procedure that confirms patient, site, laterality, procedure, and allergies.
• Confirm emergency drugs, reaction kits, and monitoring equipment are present and working before sedation.
• Communicate critical or unexpected results directly to the responsible clinician and document the recipient and time.
• Check that the report impression answers the clinical question and states any recommended next step.
• Log incidents, near misses, and equipment faults through the facility reporting system.
• Review quality indicators, peer review results, and dose trends on a scheduled basis.

★Learning sources

• Micro Degree: Diagnostic and Interventional Radiology
• Micro Degree: Healthcare Administration Practice
• Micro Degree: Physiotherapy Assistant Operations
• Micro Degree: Cardiac Care Support