Streamlining and adapting the OSCER case presentation
The new OSCER format for RANZCR exams is a certain departure from the traditional viva based format. The structure has moved away from a candidate driven presentation of live cases to a standardised question and answer format with allocated marks and marking rubrics. As such, we need to adapt how we interact with the cases being presented.
Listen to the question
Based on the sample questions and answers, there will be separate questions for observations, diagnoses/differential diagnoses and management points. As such, it will be very important to listen to what your examiner is asking and responding to the specific question. If you have been asked for "observations", time could be wasted by going into a long differential diagnosis list or debating the appropriate management plan. Describe the salient abnormalities and pull the findings together. Then wait for the next question, differential diagnosis and management plan in hand.
Hone in on the abnormality
Depending on how the case images are presented in the OSCER, that is as a series or as a static image, your approach and search strategy will need to be adapted. For a scrollable stack, you will naturally need to give yourself a couple of seconds to find the abnormality and hone in on it - but don't spend too much time doing this. For a single captured image, the abnormality should jump out at you fairly quickly.
Your practice and preparation will need to encompass drilled search strategies and pattern recognition. This will vary based on pathologies and ideally draw out the information which will be clinically important for the patient.
Get to the point
In the old exam format, I was a strong advocate for talking to give yourself "thinking time" at the beginning. This would involve repeating the history and clarifying the exam in front of you, giving you time to cast you eyes over the case and get your bearings. In the new format, there will be less time for this "throat clearing" exercise - you need to jump straight in and start reading-out the findings.
Regardless of how the exam is shown, you need to get to the point quickly and get the pertinent findings out quickly. For each case, focus on the high yield and relevant facts, that is those that will win you the most marks and drive the case forward.
You might find that asking yourself this puts things into perspective:
"If I was on a busy shift and I had 30 seconds to tell the ED doctor what was happening on the scan, what would I say?"
Streamlining your presentation
In a generic sense, I suggest starting with "what" and "where" to give a broad topic sentence. This orientates you in the scan and will aid in forming differential diagnoses. For example: "There is a large, heterogenous right retroperitoneal mass" or "There is fat stranding in the right iliac fossa".
Starting with "where" might not always be appropriate, however, particularly if there is a diffuse abnormality, e.g. the starting sentence could be "There is large volume pneumoperitoneum". If the what is unclear, focusing on the "where" primarily gives a good starting point, e.g. "The mediastinal contour is abnormal".
After starting your presentation with the salient abnormality, you can move through the characterisation of the finding and problem solving. This may encompass a "causes, complications, associated findings" approach, pair this with a staging system in the setting of malignancy (tumour, nodes, metastases), or conduct a systematic appraisal e.g. when assessing a trauma scan.
Causes, complications, associated findings
A mantra of mine for case presentation to help identify and consider the pathology as a whole. Even medical students can point out an abnormality and say "there's the problem". Where we add value as radiologists is considering the abnormality in its context:
Can I see the cause somewhere on this scan, or is there something in the clinical history which will give me a clue? How can this help to narrow down my differential diagnosis?
How is the abnormality affecting the surrounding environment in the body?
What are the common complications associated with this abnormality? Can I screen for them on the series I have been given?
Is this condition associated with other manifestations and could they be present on these images?
If you see a lung mass, for example, you could apply this framework as follows:
Are there features of smoking related lung disease? (Cause)
Is there bronchial obstruction/post obstructive bronchiectasis? Is there vascular invasion or pulmonary emboli? (Complications)
Is there evidence of nodal or visceral metastases? (Associated findings)
The more practiced this approach (or your chosen approach) is, the more streamlined your presentation will become. It is also a good way to consider whether you need to include relevant negatives, which can be a challenge in the exam setting as well as daily reporting.
Close it out
A brief conclusion will still be important if your presentation extends beyond 20 seconds or a few short sentences. Again, this should be as short and to the point as possible given the information at hand. If the diagnosis is unequivocal, you could offer it at this stage. If there is a long differential list, it may be best to hold back pending the next question from the examiner.
If you have been solely asked for your observations, you could conclude a more complex anterior mediastinal case like this: "In summary, there is a large heterogeneously enhancing anterior mediastinal mass with associated mediastinal lymphadenopathy." Try to avoid restating the findings or relevant negatives in full.
When you have concluded your presentation, however fits best, make signal to your examiner with a pause. They will ask you the next question and you carry on with your answer, building on what you already know about the case.