Related Experiment Video
Updated: Apr 19, 2026
Quantitative Mapping of Specific Ventilation in the Human Lung using Proton Magnetic Resonance Imaging and Oxygen as a Contrast Agent
Published on: June 5, 2019
Regional ventilation/perfusion mismatch pattern in patient with Swyer James (MacLeod's) syndrome
Sait Sager1, Sertac Asa1, Reşit Akyel1
1Department of Nuclear Medicine, Cerrahpaşa Medical Faculty, Istanbul University, Cerrahpasa, Fatih, Istanbul, Turkey.
Abstract:
Swyer James (McLeod's) syndrome (SJMS) is an uncommon disease, which occurs as a result of childhood bronchiolitis obliterans. Patients may not be diagnosed until later in their life. A 46-year-old man underwent ventilation/perfusion scintigraphy for acute onset of dyspnea. The scan showed markedly diminished ventilation and perfusion unilaterally on the right middle and inferior lobes. However, mismatched ventilation-perfusion pattern was shown on the upper right lobe, which was consistent with pulmonary embolism. Unilaterally matched ventilation/perfusion defect can see in SJMS in lung scintigraphy; however, when pulmoner embolism may accompany, scintigraphy should be carefully examined.
Insights
Swyer James syndrome (SJMS) can be diagnosed in adulthood, often presenting with unilateral lung defects on ventilation/perfusion scans. Differentiating SJMS from pulmonary embolism requires careful scintigraphic examination due to overlapping imaging findings.
Area of Science:
- Pulmonology
- Radiology
- Medical Imaging
Background:
- Swyer James (McLeod's) syndrome (SJMS) is a rare consequence of childhood bronchiolitis obliterans.
- Diagnosis of SJMS can be delayed until adulthood.
- Patients may present with symptoms mimicking other acute pulmonary conditions.
Observation:
- A 46-year-old male presented with acute dyspnea.
- Ventilation/perfusion scintigraphy revealed diminished ventilation and perfusion in the right middle and inferior lobes.
- A mismatched ventilation-perfusion pattern was observed in the right upper lobe, suggestive of pulmonary embolism.
Findings:
- Unilateral matched ventilation/perfusion defects are characteristic of SJMS on lung scintigraphy.
- The presence of pulmonary embolism can complicate the interpretation of scintigraphic findings in SJMS.
- Careful examination of ventilation/perfusion scans is crucial when pulmonary embolism is suspected in patients with potential SJMS.
Implications:
- This case highlights the importance of considering SJMS in adult patients with unilateral lung defects on V/Q scans.
- Accurate diagnosis requires differentiating SJMS from other conditions like pulmonary embolism, which can present with similar imaging patterns.
- Enhanced awareness and careful interpretation of scintigraphy are vital for timely diagnosis and appropriate management of SJMS.
Related Concept Videos
01:21Acute Respiratory Failure-II
The underlying physiological abnormalities that contribute to hypoxemic respiratory failure include:
01:10Atelectasis II: Pathophysiology
01:30Alterations in Respiration II
In Biot's breathing, the respiratory rate and depth are irregular, alternating between periods of deep gasping and apnea. Common causes...
01:23Acute Respiratory Failure-IV
01:29Assessment of Ventilation II: Respiratory Depth and Rhythm
Respiratory depth measures the volume of air inhaled or exhaled during a breath. It can vary from shallow to deep and typically remains consistent when a person is at rest or asleep. Occasionally, individuals will automatically inhale deeply, known as sighing, which inflates the lungs with more air than normal breathing.
To assess respiratory depth, observe the degree of chest excursion or movement:
01:19Factors Affecting Pulmonary Ventilation
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...