CT Triage for Laryngotracheal Stenosis Faces a Resource-Limited Test of Accuracy
Laryngotracheal stenosis is a potentially dangerous cause of airway narrowing, and the diagnostic problem is familiar to any clinician who has watched a patient move from mild breathlessness to audible stridor or outright respiratory failure. The condition can follow intubation-related injury, trauma, infection, autoimmune disease, or idiopathic fibrosis, but the first barrier is often recognition rather than classification. Symptoms are nonspecific, presentation varies across populations, and delays can be costly when the airway is already compromised.
This prospective study protocol sets up a direct comparison between point-of-care ultrasound and neck radiography for triage of suspected laryngotracheal stenosis in a resource-limited setting. The design is straightforward and clinically practical: consecutive patients will undergo paired testing, with both bedside imaging approaches measured against the same CT reference standard. In a condition where timing and access can shape whether a patient is stabilized or escalated, the value of a fast triage tool is obvious.
A narrow airway does not wait for referral logistics.
Paired Imaging Against a Common CT Reference Standard
The study architecture is built to support within-participant comparison rather than indirect cross-patient inference. Consecutive recruitment reduces selection drift, while paired testing allows each participant to serve as their own comparator when ultrasound and radiography are judged against CT. That structure matters because diagnostic accuracy studies can be distorted when one modality is applied to a different clinical mix than another, especially in airway disease where symptom severity and anatomy both shape the imaging readout.
Standardised acquisition and blinded interpretation are central to the protocol. Those safeguards are meant to reduce measurement and review bias, two familiar threats in imaging research where the interpreter may be influenced by prior impressions or by knowledge of the alternative test result. A planned 24-hour testing interval adds a timing buffer intended to limit bias from rapid clinical change, which is relevant when airway symptoms can fluctuate or worsen over short periods.
The protocol also specifies explicit recording of technical failures and indeterminate findings. In real-world airway assessment, those results are not peripheral; they are often the exact outcomes that determine whether a bedside tool can function as a triage test. An ultrasound examination that cannot visualize the relevant anatomy, or a radiograph that cannot confidently categorize a narrowed segment, has limited practical value even if its accuracy appears strong in ideal conditions.
Why Ultrasound and Radiography Matter Where CT Access Is Limited
CT remains the reference standard in this study, but the protocol is being framed in a setting where CT is not always immediately available. That is the core clinical question. If bedside POCUS or neck radiography can identify patients likely to have stenosis with enough reliability, clinicians may be able to prioritize urgent referral, accelerate airway planning, or avoid unnecessary transfer in patients without significant narrowing.
Ultrasound has practical appeal because it can be performed at the bedside, repeated quickly, and deployed without the infrastructure demanded by CT. In airway disease, however, operator dependence is unavoidable. Image quality can be limited by patient habitus, neck anatomy, calcification, or inability to visualize deeper structures. Neck radiography, by contrast, is familiar and more widely available, but it offers less dynamic detail and may miss subtle or anatomically complex stenoses. The protocol is designed to test whether one or both modalities can serve as realistic triage tools rather than just technically interesting substitutes.
Sensitivity, Specificity, and the Problem of Indeterminate Results
Although the abstract does not provide numeric hypotheses or sample size details, the clinical logic of the study is clear: diagnostic accuracy will determine whether either test can meaningfully redirect care. Sensitivity will matter when the priority is not to miss stenosis in a symptomatic patient. Specificity will matter when false positives would trigger unnecessary transfers, anxiety, or further testing. Indeterminate results will be especially important in this population because a triage test that frequently fails to classify patients may still impose delay rather than prevent it.
The protocol’s sensitivity analyses around technical failure and indeterminate readings should help expose where the methods are most fragile. In diagnostic research, those edge cases are often more informative than tidy positive-and-negative bins. If ultrasound performs well only when anatomy is easy to see, or if radiography becomes unreliable in ambiguous cases, then the practical adoption threshold rises quickly. Triage tools earn their place by working in difficult patients, not only in textbook scans.
Single-Centre Referral Cohort and the Limits of Generalisability
The study will recruit from a single centre among patients already referred for CT. That makes the reference standard feasible, but it also narrows external validity. A tertiary or referral cohort is not the same as a primary care triage population. Patients already sent for CT are more likely to have been selected because symptoms, severity, or diagnostic uncertainty already raised concern. As a result, the prevalence of true stenosis may be higher than in frontline settings, and accuracy estimates may not transport cleanly to clinicians deciding who should be referred in the first place.
There is also an inherent tension in using CT as the reference standard while acknowledging that CT itself is imperfect. In airway stenosis, morphology, motion, and interpretation can all influence what is counted as disease and how severe it appears. If the reference standard is imperfect, then any test paired against it may be judged against a moving target. Still, CT remains the most practical comparator for this protocol, and the study’s value lies in defining how close bedside methods can come in ordinary practice.
The pathway from symptoms to diagnosis is often the bottleneck in laryngotracheal stenosis. If this protocol can show that a bedside test reliably sorts patients who need urgent escalation from those who do not, the impact would extend beyond imaging performance into airway workflow, referral timing, and resource allocation. The unresolved issue is not whether stenosis can be serious; it already is. The question is whether accessible imaging can identify it fast enough to matter when CT is distant, capacity is limited, and respiratory decline is still on the table.