Since the development of cone beam computed tomography (CBCT), the quality of images and availability of the technique has increased rapidly. This has been in part due to the relatively low price of scanners and the technical improvements by manufacturers.
As a clinician, there are many situations in which you may decide to take a CBCT scan. Some practices may have their own scanner, while others might refer patients to a different practice or imaging centre. In both circumstances, it is possible for the image to be sent off-site for a report. This multi-centre imaging is called teleradiology, and in this article we will discuss its clerical aspects.
CBCT has been shown to be beneficial in a wide number of treatments, with common ones outlined below.
- Clinical indications: bone volume measurements, detection of local anatomy
- Example selection criteria: SEDENTEXCT section 442
Wisdom tooth removal
- Clinical indications: Root morphology and proximity to the ID canal
- Example selection criteria: SEDENTEXCT section 441
- Clinical indications: Diagnosis of pathology and surgical planning
Selection criteria is evidence-based guidance on what type of imaging may be useful in which clinical scenarios. The useful nature of CBCT is outlined in selection criteria, which has been included above.
The imaging chain
The imaging chain is the name for the processes involved in imaging. It starts with the decision to take an image, and ends with the image being reported. For dental intraoral radiography, the dentist often acts as the referrer, practitioner, operator (radiography) and operator (reporting).
From an administrative point of view, this imaging chain is very simple. For CBCT, however, it is unlikely these roles will be carried out by the same person and a whole team is likely to be involved across different sites.
Brief recap of the legislation
The Ionising Radiations Regulations (IRR) is the legislation which protects workers and members of the public. It is enforced by HSE in England, Wales and Scotland and HSENI in Northern Ireland. As part of the compliance with IRR, an imaging centre needs to have 'local rules'.
The Ionising Radiation (Medical Exposure) Regulation (IRMER) is the legislation that protects patients. It is enforced by the CQC (in England), the Healthcare Inspectorate Wales (in Wales), The Regulation and Quality Improvement Authority (in Northern Ireland) and Healthcare Improvement Scotland (in Scotland). As part of compliance with IRMER an imaging centre needs to have 'written procedures'.
There are five key roles within IRMER.
1. Legal person: person or body corporate.
- enforce the local rules
- ensures training compliance
- ultimately responsible for radiation safety.
2. Referrer: registered health care professional. Entitled to refer in the local rules. Aware of relevant selection criteria.
- must provide the practitioner with sufficient information.
3. Practitioner: registered health care professional. Expert in selection criteria.
- justifies the scan based on the risk/benefit to the patient.
4. Operator - radiography: any person involved in the practical aspects of taking the scan. May include employees (receptionist, nurse, dentist, DCP) or others (scanner engineer, IT expert).
- practical aspects of taking the scan, maintenance and QA of the scanner, and IT support.
5. Operator - reporting: registered health care professional. A dentist who has undergone extra training.
Advice on referrals
CBCT scans 'in house'
Ensure that your local rules set out which staff members can refer for CBCT. Written procedures provide guidance for which staff members are involved in the different aspects of the imaging chain.
Sending referrals to other imaging centres
Ensure you have prior agreement from the imaging centre in the form of a Service Level Agreement (SLA) so everyone involved in the imaging chain knows their role. This would mean you are 'entitled' to refer the patient to the imaging centre.
An example SLA is included as appendix C in the Health Protection Agency's Guidance on the Safe Use of Dental Cone Beam CT (Computed Tomography) Equipment.
Accepting referrals from others
Accept referrals only from those who you have a prior arrangement and SLA. It would be prudent to hold a record of the referrer's CPD relating to radiation protection and CBCT as well as their GDC registration. If you are satisfied with the information you have, you can formally record them as a referrer in the local rules. You may also ask for a referral pro forma (click here to download an example).
Ensure it is clear who is providing the report (ie, acting as the operator - reporting). More 'straightforward' scans can be reported by dentists who have undergone extra training if they feel confident in doing so.
It is strongly advised there is a formal reporting pathway in place for scans outside the area of expertise of the reporter. This will likely involve large volume scans (>10cm height), those outside the dentoalveolar region (ie, including pharynx, skull base, orbits, temporal bones) and equivocal dentoalveolar pathology. It is important to consider the security of data transfer and the training, registration and indemnity of the reporter, as per the guidelines from the Royal College of Radiology.
Dento-legal referrals for CBCT
The above guidance applies to clinical/diagnostic radiology. Any aspect of imaging for the purpose of dento-legal work is covered by a different set of rules. This is a very complex area, so it might be best that this is only undertaken under the direction of a GDC registered specialist in dental and maxillofacial radiology.
There are comprehensive guidelines produced by the European Academy of DentoMaxilloFacial Radiology which outlines a 2 tier system for CBCT training (level 1 = referrer, level 2 = reporting).
Example of a multi-centre imaging chain
A GDC registered dentist (1) has a valid and applicable SLA for referring small volume CBCT to The Imaging Centre. She provides the relevant information to enable justification, refers to named selection criteria and is entitled to refer in the local rules.
Another GDC registered dentist (2) works at The Imaging Centre and has an interest in CBCT. He is authorised in the working procedures by the legal person to undertake this role. He is an expert in selection criteria and justifies and protocols the scan.
A receptionist (3) at The Imaging Centre is authorised in the working procedures to correctly identify the patient and show them to the CBCT room. The nurse (4) is authorised in the working procedures to position the patient in the scanner. A third GDC registered dentist (5) carries out final checks, exposes the patient, and records the exposure details.
A GDC registered specialist in dental and maxillofacial radiology (6) reports the scan remotely using a secure, transparent, rapid reporting solution (see RCR standards for more on this).
The receptionist at The Imaging Centre (3) shares the images with the original referrer (1) using a secure, transparent, rapid data transfer.
Finally, an IT specialist (7) has trained the referring dentist (1) on manipulating the images and also ensures IT security.
Other aspects to take into consideration
There is potential for embarrassment to all parties if the payment terms, location and amounts are not agreed in advance.
If you are referring it is paramount to express the urgency. One simple way to do this is with a traffic light system; for example, Red = within two weeks, Amber = six weeks, Green = within 20 weeks.
It would be prudent to have all parties in the imaging chain aware of your current standards and practices relating to COVID-19. Communication with all the people in the chain is key.