Health Technology · Supplementary · from Health Technology
Case 1: AI-Assisted Radiology Diagnosis Error
Patient Presentation
Demographics: 54-year-old female office manager
Chief Complaint: "My doctor said the AI found something on my chest X-ray and I need more tests."
History of Present Illness: A 54-year-old woman underwent a routine pre-operative chest X-ray prior to elective cholecystectomy. The radiology department utilizes a commercially available AI-assisted detection system for preliminary reads. The AI algorithm flagged a 1.2 cm opacity in the right upper lobe as "suspicious for malignancy" with a confidence score of 87%. The patient was informed of the finding and referred for CT imaging.
Upon CT chest with contrast, no discrete pulmonary nodule was identified. The opacity seen on chest X-ray corresponded to an overlap of the first rib and clavicle creating a pseudo-nodule artifact. The AI system had generated a false-positive result, causing significant patient anxiety and a two-week delay in her elective surgery.
A retrospective review of the AI system's performance over the prior quarter revealed a false-positive rate of 11.3% for pulmonary nodule detection, with bone overlap artifacts being the most common cause (38% of false positives). The attending radiologist had not reviewed the AI-flagged image before the result was communicated to the referring physician.
Past Medical History:
- Cholelithiasis (symptomatic)
- Hypertension, well-controlled
- Anxiety disorder
Medications:
- Lisinopril 10 mg daily
- Sertraline 50 mg daily
Social History:
- Never smoker
- Social alcohol use
- Works as office manager, sedentary lifestyle
Family History:
- Mother: breast cancer at age 67
- No family history of lung cancer
Physical Examination
- Vital Signs: BP 138/86 mmHg, HR 88 bpm, RR 16/min, Temp 36.8°C, SpO2 99% on room air
- General: Anxious-appearing female, tearful during examination
- Lungs: Clear to auscultation bilaterally, no wheezes or crackles
- Cardiovascular: Regular rate and rhythm, no murmurs
- Abdomen: Mild RUQ tenderness, positive Murphy's sign
Workup and Results
Laboratory Studies:
| Test | Result | Reference Range |
|---|---|---|
| WBC | 7,200/µL | 4,500-11,000/µL |
| Hemoglobin | 13.8 g/dL | 12.0-16.0 g/dL |
| CEA | 1.2 ng/mL | <3.0 ng/mL |
| ALT | 42 U/L | 7-56 U/L |
| AST | 38 U/L | 10-40 U/L |
Imaging/Additional Studies:
- Chest X-ray (AI-flagged): 1.2 cm opacity in right upper lobe, AI confidence score 87% for malignancy
- CT Chest with contrast: No pulmonary nodule identified; opacity on X-ray corresponds to first rib-clavicle overlap artifact; lungs clear bilaterally
- AI System Audit: False-positive rate 11.3% over prior quarter; bone overlap artifacts accounted for 38% of false positives
Clinical Image
Diagram illustrating how overlapping bone structures on chest X-ray can create pseudo-nodule artifacts that trigger false-positive AI detection alerts. Source: Educational illustration.
Diagnosis
AI-Generated False-Positive Pulmonary Nodule Detection Due to Bone Overlap Artifact
Key Diagnostic Criteria:
- AI system flagged opacity with high confidence score
- CT chest confirmed no true pulmonary nodule
- Opacity corresponded to anatomical bone overlap (first rib and clavicle)
- Workflow gap: AI result communicated before radiologist review
Treatment Plan
- Reassurance and patient education regarding the false-positive finding
- No pulmonary follow-up required
- Proceed with elective cholecystectomy as originally planned
- Implement mandatory radiologist verification before AI results are communicated to referring physicians
- Retrain AI model with augmented dataset including bone overlap artifacts
- Establish departmental protocol for AI-assisted reads requiring attending sign-off
Key Learning Points
- AI diagnostic tools are adjuncts to, not replacements for, physician clinical judgment
- False-positive results from AI systems can cause significant patient harm through anxiety, unnecessary testing, and treatment delays
- Bone overlap artifacts on chest X-ray are a well-known source of false-positive AI detections
- Institutional protocols must mandate physician review of AI-flagged findings before results reach patients or referring providers
- Regular performance audits of AI diagnostic systems are essential for quality assurance