Designing a workshop for a temporal artery biopsy simulation

Abstract

Purpose

To evaluate a wet-lab session designed to teach temporal artery biopsy (TAB) using simulation.

Methods

The Welsh Institute for Minimal Access Therapy Team (WIMAT) developed two simulation models using pig ureter for the temporal artery. The session consisted of consultant-led teaching on TAB surgical approaches, mapping the temporal artery with a Doppler device, and practical demonstrations with videos. Trainees performed two biopsies using the models under consultant supervision. Participants completed questionnaires to evaluate their pre- and post-session knowledge, understanding, and learning experiences. Three key areas of comparison were mapping the temporal artery, using an ultrasound doppler device, and performing a TAB.

Results

Seven specialist trainees (ST1-5) and 3 staff grade surgeons, supervised by 3 consultants, participated. Paired t test sampling showed statistically significant improvements in mapping the temporal artery (P = 0.0076), using an ultrasound Doppler device (P = 0.0002), and performing a TAB (P = 0.0002). Identified barriers included lack of knowledge, limited prior procedures, concern about damaging the facial nerve, and lack of senior support/supervision, which contributed to trainees’ apprehension about performing TAB.

Conclusions

This innovative teaching event offers a blueprint for medical training programs to improve TAB training. Modern surgical education benefits from wet labs with expert supervision.

Introduction

Giant cell arteritis (GCA), also known as temporal arteritis (TA), is the most common form of large- and medium-vessel vasculitis in adults. Patients are typically >50 years of age and present with a plethora of systemic symptoms, including headache, jaw pain, and vision loss. Patients may present to general practitioners, optometrists, rheumatologists, or ophthalmologists. Vision loss is irreversible; if left untreated, the initially unaffected eye can also lose vision. GCA carries a risk of stroke and must therefore be treated urgently.

There is no single test to diagnose GCA; rather, a combination of the patient’s clinical picture, biochemical markers, and, where available, ultrasound imaging of the temporal artery and or a temporal artery biopsy (TAB) are used to make a definitive diagnosis. If there is a high clinical suspicion of GCA, then treatment is initiated with high-dose corticosteroids, and the aforementioned investigations can be performed soon after starting treatment. According to the British Society for Rheumatology guidelines on the diagnosis and treatment of GCA,1 a confirmatory test is needed in patients with suspected GCA: temporal artery biopsy of at least 1 cm, ultrasound of the temporal and axillary arteries, or both.

As part of the current ophthalmology specialty training program in the United Kingdom, trainees are required to have performed two TABs during their 7-year training path. It may be difficult, however, for trainees to comply with this requirement if such services are unavailable at their hospital or they are available but infrequently performed. This lack of opportunity ultimately affects the quality of patient care and patient safety. To address the lack of opportunity, one of the authors (SR) organized, designed, and delivered a novel TAB workshop for trainees. A structured, regular program of TAB simulation training has the potential to provide trainees with adequate education especially where enough procedures are not available.

Materials and Methods

In July 2023, at The Welsh Institute for Minimal Access Therapy (WIMAT) Centre in Cardiff, the first author (SR), with the support of two ophthalmology consultants (AH, PW), one vascular consultant surgeon (IW), and two professional specialists (PH, CF) delivered a half-day surgical simulation laboratory to teach ophthalmology specialist trainees how to perform a TAB. The workshop consisted of an interactive didactic component followed by simulation training. As part of the teaching, which included a refresher on the anatomy of the region in question, emphasis was placed on avoidance of the “danger zone,” where there can be risk of damaging branches of the facial nerve. Attendees would later be asked to map the danger zone on the models used. Case studies, surgical videos, and animations were used as teaching tools. This multifaceted approach was designed to appeal to different types of learners. Interactive real-life case scenarios allowed attendees to practice their clinical decision making.

Simulation training consisted of an integrated and comprehensive series of practical activities aimed at future clinical practice. Attendees worked in pairs for the practical component, which allowed for reversible roles of “primary surgeon” and “assistant.” This also enabled active feedback to facilitate collaborative learning. Supervision and teaching were provided by the 3 consultants (PW, AH, IW), responsible for three small groups (two groups consisted of 3 participants, and one consisted of 4). The consultants were also given freedom to freely circulated amongst the other groups during the session to provide feedback and assistance. Each step of the procedure was completed independently by each attendee. The models for simulation training were developed by the authors in house (PH, CF, SR, AH) over a 6-week period. The core ideas regarding the components of the model (PH) were refined based on feedback.

Constructing the Models

Initially a protype model was developed (PH, CF) prior to the event to test the practicality and feasibility of using such a model. With input from clinicians (AH, SR), the final modified models were altered to be used for the training. A total of 22 models were constructed, 2 models per attendee and 2 extra models to be trialed by the consultant on the day of the event to familiarize them with the workings of the model.

The model consisted of a suture pad (150 × 100 mm) with the superficial temporal artery represented by a porcine ureter of approximately 120 mm in length, chosen because of its close approximation of the temporal artery size (1.9 vs 1.7 mm, resp.). The ureter was inserted under the surface membrane 5–10 mm in depth, as shown in Figure 1, to represent the anatomical variation in patients. The distal end of the vessel (ureter) was clipped using Ligamax 5 clips (Ethicon Endo-Surgery), with the proximal end plumbed using a 4.5 Fr TAUT operative cholangiogram catheter (Teleflex Medical, Morrisville, NC). To this, a 10 ml syringe containing simulated blood (Limbs&Things, Bristol) under mild pressure was attached to simulate active bleeding in the event of vessel transection due to suboptimal technique. Additionally, a 3-0 undyed polyglactin 910 suture was also tunneled in proximity to the vessel to represent the temporal branch of the facial nerve to allow participants to acknowledge the risk of damage to the facial nerve, a common complication in TAB. This model was dressed with surgical drapes to simulate the area of exposure required for a TAB (Figure 2). The model included an attached ear to help attendees judge and appreciate relative and proximal real-life anatomy. Models were also painted in various skin tones to represent variation in patient groups and demonstrate the visual differences regarding the subdermal vessels (Figure 1).

Figure 1.

Models used, showing the variation in depth of the frontal branch of the superficial temporal artery model. Model A (left) shows the superficial temporal artery inserted at a depth of 5 mm from the surface membrane. Model B (right) shows the superficial temporal artery inserted at a depth of 10 mm from the surface membrane.

Figure 2.

Mapping of the temporal artery and depiction of the danger zone.

Model 1 was constructed to be less complex, with the temporal artery located superficially. After successfully completing the TAB on model 1, attendees were encouraged to move onto the more complex model 2, in which the temporal artery was located deeper. Attendees were given the opportunity to practice locating the temporal artery using the ultrasound doppler probe (Figure 3). Figure 4 shows exposed temporal arteries ready to be biopsied.

Figure 3.

A consultant using the ultrasound doppler device to locate the temporal artery on one of the attendees.

Figure 4.

Exposed temporal arteries ready to be biopsied. A, The more “straightforward” model used as the temporal artery was inserted superficially into the model, thus making identification relatively easy. B, The more complex model showing the deeply situated temporal artery. Marking on the model indicates the path of the temporal artery and the danger zone.

The simulation lab was open to a maximum of 10 ophthalmology trainees. Collaboration between different surgical disciplines aimed to enhance the trainee experience by letting them interact with vascular and ophthalmic surgeons. Before and after the event, participants were asked to complete a 30-item Google forms questionnaire (provided as article supplement), the results of which could be used to evaluate pre- and post-session knowledge and assess learning experiences. The pre-training event survey was completed by participants 1 week prior to the event; the post-training survey, 1 week after the event. A link to the questionnaire was sent to the attendees that had registered to attend the event pre- and post-event. The feedback form consisted of a series of mainly Likert scale response items (using poor, average, good, and excellent), with some free-text response options. Likert scales provide reliable and valid data and are used widely in psychometric research.2,3 A paired sample t test was performed, and P values were calculated.

Results

Ten attendees participated in the course, and 10 completed the end-of-course evaluation. Of the 10 attendees, 7 were ophthalmic specialist trainees (OST), and 3 were trust grade doctors. There were 3 year-3 trainees (30%), 2 year-5 trainees (20%), 1 year-4 trainee (10%), and 1 first-year trainee (10%). Of the 10 attendees, 9 were from the Wales Deanery; 1 attendee was from the South London Deanery.

In response to the question regarding opportunities to perform TAB at their local hospitals, 6 said opportunities were “poor,” and 3 said that they were “fair.” Half of the participants stated that the level of training received to perform TAB prior to this event was “poor,” whereas 4 stated it was “fair.” Prior to this event, 2 attendees had never performed a TAB, 6 had performed 1, 1 had performed 2, and 1 had performed 3.

Questions 6–11 asked attendees to evaluate pre- and post-course knowledge, understanding, and skills. The general findings from these questions (Figure 5, Table 1) demonstrate that across all domains, attendees stated that their knowledge, understanding and skills had improved. All of the results were statistically significant (P < 0.05). Of note, 8 of the 10 of attendees felt that vascular surgeons should perform a TAB, 10 had only ever received informal TAB teaching, and only half were aware of the anatomical danger zone landmark.

Figure 5.

Comparing pre- and post-event knowledge and understanding pertaining to mapping the temporal artery, using an ultrasound doppler to detect the temporal artery and one’s ability to perform a temporal artery biopsy.

Table 1.

Comparing the pre- and post-event results and illustrating their associated levels of statistical significance.

For the free-text question 16, “Do you feel apprehensive about performing a TAB in clinical practice? If so, why?” all participants felt more confident after training. One trainee stated, “I did prior to this event as I lacked basic common knowledge regarding how to perform this procedure. I was also fearful of the nearby anatomical structures and did not want to damage them. Also, within my department no members of the ophthalmology team were performing TABs for patients and so senior support/supervision was lacking.” Of the 10 attendees, 7 had observed 2–5 TABs in clinical practice.

Seven attendees felt that the models were realistic and acknowledged an increase in complexity from model 1 (where the temporal artery was located superficially) and model 2 (where it was located deeper within the model), with 5 stating that model 1 provided a level of complexity that was easy and 7 stating that model 2 was difficult.

The venue was graded as “excellent” by 7 attendees. As part of the course evaluation, attendees were asked to provide an open-ended response on how the course supported their learning needs and how it could be improved. Overall, the course was very well received, with a mean rating of 5/5.

All attendees (10 of 10) affirmed an intention to use what they had learned in their future clinical practice.

Discussion

GCA does not affect every part of every temporal artery. Therefore, it can “skip around,” creating so called “skip lesions.” For a patient to be clinically positive but biopsy negative is not uncommon. The published literature confirms undesirably high false negative rates and a low yield for biopsy.2 Sampling of the incorrect tissue, inadequate sample length, and steroid exposure prior to biopsy are potential reasons for reduced sensitivity of TAB results.3,4 Clinicians therefore can and do opt against performing an invasive TAB (more so when the ultrasound route is available) while treating patients with a high clinical suspicion of GCA. A difficulty with this noninvasive approach is that when the rheumatologists under whom such patients will be under long-term care must make difficult decisions regarding indications for ongoing corticosteroid therapy and the duration of therapy, GCA is conjectural rather than proved. Armed with a positive TAB result for GCA, in the face of systemic upset (eg, hypertension, diabetes, osteoporosis) and an anxious patient, a rheumatologist can justify a decision with respect to ongoing steroid therapy. A recent study investigating quality standards for the care of people with GCA in secondary care5 found that a TAB service needs to be well resourced and not dependent on a single surgeon. A robust well-developed pathway is imperative.

TAB remains an important tool for diagnosing GCA and to rationalize ongoing treatment; however, instruction in this important procedure remains largely informal. To our knowledge, this multidisciplinary TAB simulation lab was the first in the United Kingdom: our search of the published literature (using PubMed, Medline, Web of Science, and Scopus, in the English language and up to July 31, 2023) identified no reported methods of practicing TAB either using cadaveric specimens or purpose-built models. The key words searched included TAB simulation, cadaveric specimens, and TAB models.

A 2002 study6 carried out at King’s College Hospital London investigated the differences between surgical specialties (ophthalmologists vs vascular surgeons vs plastic surgeons) performing TAB and found that ophthalmologists were achieving the longest average length of biopsies, which reduces the risk of obtaining “skip lesions,” and advocated that ophthalmologists were best suited to performing most biopsies. They were also more likely to re-biopsy if needed.6 Currently ophthalmology trainees in the United Kingdom are required to achieve competence in TAB by the end of their 7th and final year of training. Ideally, trainees would be performing TABs more frequently and throughout their entire training programs to hone their skills. Simulation-based training can help trainees acquire the core skills and knowledge required for TABs and establish clear learning objectives.

Our training course addresses a gap in the formal teaching of TAB, which is a complex and specialized procedure. The development of a standard formal teaching curriculum would help to ensure that all trainees would finish training with the key knowledge and skills to perform TAB. Surgical complications of TAB can be reduced by ensuring a structured curriculum, with a multifaceted learning approach (wet labs and simulation), as with current approaches to teaching cataract surgery.7 Osei et al8 advocated for the teaching of important anatomical landmarks, including identification of danger zones, risks and benefits of the procedure, and step-by-step guide with supporting video. Our teaching event fulfilled all of these criteria. The authors also ensured that McGaghie’s best practice principles of simulation-based education (ie, curriculum integration, simulation fidelity, and team training) were fulfilled.9 Additionally, collaboration across surgical disciplines provided trainees insight and access to, for example, vascular surgeons, to which ophthalmologists would otherwise not normally have exposure. The peer learning approach deployed also helped with engagement, interaction, participation, and enjoyment.

In clinical practice, the traditional teaching approach persists: see one, do one, teach one. However, in an era where simulation training is readily available (especially in developed countries), this approach has become less acceptable and is regarded as unethical by some, who raise concerns about patient safety.10,11 Our teaching event addresses these concerns and provides a blueprint for a repeatable and robust teaching experience for the benefit of trainees and patients. When trainees actively participate in the learning process, their motivation to achieve is engaged.12

Simulation training helps to achieve competency-based training goals. Early surgical exposure, technical prowess, and the assimilation of skills are key aims of any simulation training. It is a safe, realistic, and standardizable modality not only for teaching and training but also for performance assessment. Simulation training offers the opportunity to develop and nurture transferable skills into clinical practice.13 Trainers and trainees can collaboratively map out achievable goals, which is important under the current rotation-based training system. Moreover, this approach can aid in appropriate case selection for trainees. A frequently overlooked benefit of training by means of simulation and wet lab is that supervisors understand the ability of trainees prior to their stepping into operating theater. In this context, the EyeSi surgical stimulator, a cataract training system, has been shown to improve trainee confidence, reduce operating times, and reduce intraoperative complications.14–18

Most trainees face difficulties with both achieving the level of training required for and finding opportunities to perform TABs at their local hospitals. Most trainees have performed very few TABs. Our approach can help trainees gain the knowledge and technique necessary for mapping the temporal artery, using an ultrasound doppler to locate the temporal artery, and executing a TAB. Our responses to the trainee questionnaire identified lack of knowledge, inexperience, concern for the facial nerve, and lack of senior support and supervision as reasons for trainee apprehension when it comes to performing TABs.

In August 2024 the Royal College of Ophthalmologists will launch their new curriculum, “Curriculum 2024.” In this General Medical Council–approved curriculum, there will no longer be a minimum set number of TABs that trainees need to perform at level 3 (the expected level of a general ophthalmologist) ophthalmology training in the UK. However, being able to locate the temporal artery with an ultrasound probe, being able to perform a TAB, and understanding its risk and benefits are expected standards of trainees for oculoplastics level 4 (independent specialist) training. We believe that given that GCAs can present with visual loss, it is important for all ophthalmology trainees to know the principles of TAB and ideally be able to perform it. Despite the promise of our approach, models can never be a substitute for “real” anatomy (cadavers). The authors plan on developing a hybrid model to more closely replicate “real life” anatomy. Two areas for improvement include: (1) replacing the spongy material/core component within the suture pad, which was a little too “bouncy”/elastic and soft, making tissue handling and suturing a little unrealistic, and (2) adjusting the tautness of the skin overlying the suture pad, which presented challenges in creating the initial incisions. Future goals for our workshop include the creation of a formal and standardized web-based curriculum that could even be taught, for example, at ophthalmological conferences where simulation training opportunities are now being offered.

Literature Search

PubMed, MEDLINE, Web of Science, and Scopus were searched on July 31, 2023, for English-language results using the following terms: TAB simulation, cadaveric specimens, and TAB models.