KJY (2023): incidental findings and the duty to review the whole image

KJY v University College London Hospitals NHS Foundation Trust

[2023] EWHC 2719 (KB)
High Court, King’s Bench Division
Mr Dexter Dias KC, sitting as a Deputy High Court Judge
Judgment delivered: 25 July 2023

Anonymisation applies. The claimant must be referred to as KJY and his mother and litigation friend as LMD. Information capable of identifying the claimant or his immediate family must not be published.

Background

KJY was born by Caesarean section on 14 October 2010. Shortly after birth, he experienced choking and difficulty tolerating feeds. Three abdominal radiographs were obtained on 15 and 16 October to investigate possible gastrointestinal malrotation and related abdominal pathology.

The examinations were not requested to assess the hips. However, the pelvis and proximal femora were included on the images.

Two radiologists reviewed the examinations. Neither reported any hip abnormality. One radiologist reviewed the first image once. The second radiologist reviewed the available images on several occasions, giving him multiple opportunities to assess the included hip region.

At 14 months of age, KJY was diagnosed with bilateral developmental dysplasia of the hips. The condition had serious and lasting consequences, including impaired mobility and repeated surgery.

The trial was confined to whether the radiologists had breached their duty of care by failing to identify and report the hip abnormality or possible abnormality on the neonatal images. Causation and quantum were not determined.

Common ground

The parties agreed that:

all three radiographic examinations demonstrated abnormal hip alignment.
the examinations were of adequate diagnostic quality.
the radiologists were required to review the whole image.
every part of the image required professional and diligent assessment.
any identified abnormality or possible abnormality had to be reported.
incidental findings were not excluded merely because they were unrelated to the referral question.
the radiologists knew the important imaging features of developmental dysplasia of the hip.
neonatal radiographs are not the preferred investigation for diagnosing developmental dysplasia.
ultrasound is the preferred diagnostic modality in neonates.
hip abnormalities may nevertheless be visible on conventional radiographs.
the radiologists were not required routinely to draw alignment lines, measure acetabular angles or make a definitive diagnosis of developmental dysplasia.

The central dispute was therefore narrow: were the abnormalities sufficiently apparent that no reasonable and responsible radiologist would have failed to identify and report them?

The competing cases

The claimant submitted that the abnormal position and alignment of the proximal femora were sufficiently clear to require reporting. At minimum, the appearances created an index of suspicion that a hip abnormality might be present and warranted clinical review or targeted ultrasound.

The defendant argued that the findings were too subtle to be identified prospectively. They were said to become apparent only retrospectively, once the subsequent diagnosis of bilateral developmental dysplasia was known.

The legal test

The claimant bore the burden of proving breach of duty on the balance of probabilities.

The court applied the professional standard derived from Bolam v Friern Hospital Management Committee, subject to the logical scrutiny required by Bolitho v City and Hackney Health Authority.

In a diagnostic case, the court must distinguish between:

what was objectively shown on the images.
whether a reasonably careful radiologist could have failed to identify it.
whether a reasonably competent radiologist could properly have treated the examination as showing no reportable abnormality.

The existence of competing expert opinions does not determine the outcome. The court must assess the reasoning supporting each opinion and decide the issue for itself. An expert’s view cannot protect a defendant merely because it is honestly held or expressed by an appropriately qualified practitioner. It must also be responsible, reasonable and logically defensible.

The correct formulation was not whether a reasonable body of radiologists would have identified the abnormality. The question was whether no reasonable and responsible radiologist would have failed to identify it.

Professional reporting standards

The applicable professional guidance required radiologists to:

address the clinical question.
assess the whole image for expected and unexpected findings.
use both active and passive observation.
identify unequivocal abnormalities.
identify findings that might be abnormal.
report relevant incidental pathology.

The court accepted that professional standards are an important starting point rather than a conclusive legal test. Whether a departure amounts to negligence remains a matter for the court after considering all the evidence.

By the end of the trial, there was no material dispute that the entire image had to be reviewed with appropriate professional care. The fact that the examination had been requested for gastrointestinal symptoms did not reduce the required standard of scrutiny applied to the included hips.

The duty to review the whole image

The court identified three responsibilities when reviewing the neonatal radiographs:

answer the clinical question.
identify other clear abnormalities.
identify findings that might represent an abnormality.

A radiologist’s duty does not end once the referral question has been addressed. The review must extend to all anatomy included on the image.

An incidental finding is not subject to a lower standard merely because it lies outside the clinical indication. Its incidental nature may affect the order in which the image is examined, but it does not remove the obligation to identify and report it when sufficiently apparent.

Diagnosis was not required

The radiologists were not required to diagnose developmental dysplasia definitively from the abdominal radiographs.

The relevant question was whether the images demonstrated:

abnormal alignment.
a possible abnormal relationship between the proximal femur and acetabulum.
sufficient uncertainty to justify recording a possible abnormality.

Radiology is often indicative rather than definitive. A reportable observation may therefore be that an abnormality may be present, with a recommendation for clinical correlation or targeted imaging.

The fact that ultrasound was the preferred diagnostic test did not make the radiographic findings irrelevant. Nor did it relieve the reporting radiologists of the obligation to report an apparent or possible abnormality visible on the examinations before them.

The claimant’s expert evidence

The claimant’s expert, a consultant paediatric radiologist with musculoskeletal experience, considered that the abnormal alignment was apparent on the relevant images.

Her principal observations included:

abnormal orientation of the proximal femur.
malalignment between the femur and the expected position of the acetabulum.
an unusually wide relationship between the femur and ischium.
appearances that were, at minimum, suspicious for a hip abnormality.

The expert used PACS annotations and alignment lines to demonstrate the abnormalities to the court. She did not suggest that the original radiologists were negligent because they had failed to draw those lines. The annotations illustrated the anatomical relationship supporting her opinion.

She accepted during the litigation that the left hip on one image was difficult to assess and withdrew criticism relating to that particular appearance. The court regarded that concession as evidence of balanced and reflective expert practice rather than a weakness in her overall opinion.

The court also considered whether knowledge of the eventual diagnosis had created hindsight or outcome bias. It found no evidential basis for concluding that such bias had materially impaired her reasoning. Awareness of a diagnosis may focus an expert’s attention, but it does not necessarily invalidate the resulting opinion. The court instead examined whether the opinion remained logical and consistent with the images and the wider evidence.

The defendant’s expert evidence

The defendant’s expert considered the abnormalities subtle and maintained that responsible radiologists could reasonably have missed them.

The court identified several significant difficulties with that evidence:

his report initially suggested that reviewing the hips was not a necessary part of assessing a neonatal abdominal radiograph.
that position was inconsistent with the governing professional standard and was modified at trial.
he moved between describing detection as “almost impossible” and “extremely difficult”.
he appeared to require near-dislocation before an abnormality became reportable.
he disclosed a personal practice of not reporting some observed signs of neonatal hip subluxation, relying instead on later clinical screening.
that approach was difficult to reconcile with the obligation to report an identified or possible abnormality.
his reasoning did not adequately accommodate the distinction between making a definitive diagnosis and identifying a possible abnormality.

The court considered parts of his approach inconsistent, implausible and insufficiently aligned with accepted professional standards. It therefore rejected his opinion on the central issue.

The court’s assessment of expert evidence

The court strongly preferred the claimant’s expert evidence because it was:

consistent with the appearances on the images.
responsive to the applicable professional standards.
anatomically coherent.
appropriately focused on possible abnormality rather than definitive diagnosis.
internally consistent after proper concessions had been made.
supported by the evidence of the reporting radiologists concerning their own training and usual practice.

The court emphasised that expert evidence assists but does not replace judicial evaluation. The judge must test each opinion against:

the images and other objective evidence.
the contemporaneous documentation.
professional guidance.
the expert’s assumptions.
internal consistency.
concessions made during the proceedings.
changes of position.
the expert’s clinical experience.
the logic of the conclusion.

Qualifications and good faith are important but insufficient. The decisive consideration is whether the opinion withstands logical and evidential scrutiny.

Multiple misses do not establish reasonable practice

Both reporting radiologists failed to identify the abnormality. One radiologist had several opportunities to review the images.

The court took those failures into account but rejected circular reasoning. It could not be assumed that the abnormality was reasonably missable merely because two clinicians had missed it.

An independent professional standard remained necessary. Otherwise, the fact constituting the alleged negligence would itself become the justification for concluding that there had been no negligence.

The relevant comparison was with the conduct of a reasonable and responsible radiologist, informed by expert evidence, professional standards and the objective appearances on the images.

Findings on breach

The court found that the hip malalignment was clear enough that all reasonable and responsible radiologists should have identified at least a possible abnormality.

In relation to the first radiologist, the court found that:

the hip region was not examined with reasonable and sufficient care.
the abnormal alignment was missed.
the fact that developmental dysplasia was not specifically “on his mind” did not excuse the omission.
the appearances created at least an index of suspicion requiring reporting.

In relation to the second radiologist, the court found that:

he had repeatedly reviewed the images.
he accepted that he examined the hip region and looked for subtle abnormalities.
the abnormalities were present on the relevant images.
he failed to identify any of them.
no reasonable and responsible radiologist would have failed to recognise at least a possible hip abnormality.

The defendant was therefore found to have breached its duty of care.

Causation was not decided

The judgment resolved breach of duty only.

The court did not determine:

whether reporting the abnormality would have led to immediate ultrasound.
whether earlier investigation would have resulted in earlier treatment.
whether earlier treatment would have changed the claimant’s clinical outcome.
the extent of any avoidable injury.
the appropriate amount of damages.

The seriousness of the claimant’s subsequent condition and treatment did not form part of the court’s reasoning on breach.

Significance for radiological practice

Review the entire image. The referral question defines the principal clinical purpose but not the outer boundary of the radiologist’s responsibility.
Apply appropriate care throughout. Anatomy outside the immediate area of interest is not subject to a lesser standard of review.
Report possible abnormalities. The duty is not confined to findings that permit a definitive diagnosis.
Incidental does not mean immaterial. An unrelated finding must be reported when it is sufficiently apparent and potentially significant.
Do not rely on later clinical screening. An existing or possible abnormality should not be left unreported because another clinician or screening process may identify it subsequently.
Use available tools where appropriate. PACS magnification, comparison and measurement may assist when an area raises concern, although every examination does not require formal measurements.
Avoid circular reasoning. The fact that several radiologists missed a finding does not establish that missing it was reasonable.
Separate detection from diagnosis. A finding may require reporting and further investigation even where the modality cannot establish its precise cause.
Document uncertainty constructively. Where appearances may be abnormal, the report should say so and identify any appropriate next step.
Consider cognitive bias without speculation. Hindsight and outcome bias are legitimate concerns, but their presence and material effect require evidential assessment.

Significance for expert witnesses

Use the correct legal formulation: whether no reasonable and responsible radiologist would have failed to identify the finding.
Distinguish clearly between identifying an abnormality, diagnosing a condition and recommending further investigation.
State the factual and clinical information provided in the letter of instruction.
Address the professional standards applicable at the material time.
Explain whether annotations or measurements demonstrate an opinion or define the required clinical practice.
Avoid holding the defendant to a subspecialist or retrospective standard.
Reconsider earlier conclusions when the evidence changes.
Make appropriate concessions rather than defending an unsustainable position.
Ensure that personal clinical practice accords with the professional standard relied upon.
Test the opinion against the whole evidential picture rather than isolated image features.

Practical framework for incidental findings

When assessing whether an incidental finding required reporting, consider:

Was the relevant anatomy included and adequately demonstrated?
Was the image of sufficient quality for meaningful assessment?
What would a competent radiologist know about the normal appearance?
Was there a clear abnormality or an appearance that might be abnormal?
Was the finding clinically material despite being unrelated to the referral?
Did identifying it require routine observation or unusually specialised knowledge?
Was definitive diagnosis possible or merely suspicion required?
Would magnification, comparison or another PACS function reasonably have assisted?
Was the uncertainty communicated in the report?
Was appropriate further assessment recommended?
Does supporting expert opinion reflect the professional standards applicable at the time?
Is the expert’s reasoning logical, consistent and independent of hindsight?

Educational case commentary only. It is not legal advice and is not a substitute for the full judgment. The claimant and his family remain protected by an anonymity order. The publication date above is the date of this commentary, and judgment was delivered on 25 July 2023.