Diseases Involving the Central Bronchi: Multidetector CT for Detection, Characterization, and Differential Diagnosis

Congenital Lung Anomalies in Adults

Congenital lung anomaly (CLA) refers to a rare group of malformations that are typically identified prenatally or in early childhood. However, a significant proportion of cases evade detection until adulthood and either are incidentally discovered or manifest with symptoms of recurrent respiratory infection or pulmonary hemorrhage. While most CLAs have characteristic imaging findings at CT and MRI, they remain a diagnostic challenge due to the infrequency with which they are encountered in adults. Radiologists frequently play a pivotal role in suggesting the diagnosis and guiding appropriate management strategies, and recognition of characteristic imaging patterns is crucial for accurate diagnosis. The authors examine the imaging appearances and clinical manifestations in adult patients with CLA, with a focus on patients who have bronchopulmonary involvement and those with combined bronchopulmonary and vascular anomalies. Entities discussed include bronchogenic cyst, bronchial atresia, congenital lobar overinflation, congenital pulmonary airway malformation, proximal interruption of the pulmonary artery, bronchopulmonary sequestration, hypogenetic lung syndrome, placental transmogrification of the lung, and hybrid lesions. Common complications that may arise in these patients are discussed and illustrated. ©RSNA, 2024 Supplemental material is available for this article.

Raman-Guided Bronchoscopy: Feasibility and Detection Depth Studies Using Ex Vivo Lung Tissues and SERS Nanoparticle Tags

Image-guided and robotic bronchoscopy is currently under intense research and development for a broad range of clinical applications, especially for minimally invasive biopsy and surgery of peripheral pulmonary nodules or lesions that are frequently discovered by CT or MRI scans. Optical imaging and spectroscopic modalities at the near-infrared (NIR) window hold great promise for bronchoscopic navigation and guidance because of their high detection sensitivity and molecular/cellular specificity. However, light scattering and background interference are two major factors limiting the depth of tissue penetration of photons, and diseased lesions such as small tumors buried under the tissue surface often cannot be detected. Here we report the use of a miniaturized Raman device that is inserted into one of the bronchoscope channels for sensitive detection of “phantom” tumors using fresh pig lung tissues and surface-enhanced Raman scattering (SERS) nanoparticle tags. The ex vivo results demonstrate not only the feasibility of using Raman spectroscopy for endoscopic guidance, but also show that ultrabright SERS nanoparticles allow detection through a bronchial wall of 0.85 mm in thickness and a 5 mm-thick layer of lung tissue (approaching the fourth-generation airway). This work highlights the prospects and potential of Raman-guided bronchoscopy for minimally invasive imaging and detection of lung lesions.

Preoperative Thoracic CT Findings Associated With Postoperative Mechanical Ventilation in Patients Undergoing Major Abdominal or Pelvic Surgery: A Matched Case-Control Study

Background: Postoperative prolonged mechanical ventilation is associated with increased morbidity and mortality. Reliable predictors of postoperative mechanical ventilation after abdominal or pelvic surgeries are lacking. Objective: To explore associations between preoperative thoracic CT findings and need for postoperative mechanical ventilation after major abdominal or pelvic surgeries. Methods: This retrospective case-control study included patients who underwent abdominal or pelvic surgeries (01/01/2014-12/31/2018) and underwent preoperative thoracic CT. Cases were patients who required postoperative mechanical ventilation. Control and case patients were matched at a 3:1 ratio based on age, sex, body mass index, chronic obstructive pulmonary disease, smoking status, and surgery type. Two radiologists (R1, R2) reviewed CT images. Findings were compared between groups. Results: The study included 165 patients (70 female, 95 male; mean age 67.0±9.7 years; 42 cases, 123 matched controls). Bronchial wall thickening and pericardial effusion were more frequent in cases than controls for R2 (10% vs 2%, p=.03; 17% vs 5%, p=.01), but not R1. Pulmonary artery diameter was greater in cases than controls for R2 (2.9±0.5 cm vs 2.8±0.5 cm, p=.045) but not R1. Right lung height was lower in cases than controls for R1 (18.4±2.9 cm vs 19.9±2.7 cm, p=.01) and R2 (18.3±2.9 cm vs 19.8±2.7 cm, p=.01). Left lung height was lower in cases than controls for R1 (19.5±3.1 cm vs 21.1±2.6 cm, p=.01) and R2 (19.6±2.4 cm vs 20.9±2.6 cm, p=.01). Anteroposterior chest diameter was greater for cases than controls for R1 (14.0±2.3 cm vs 12.9±3.7 cm, p=.02) and R2 (14.2±2.2 cm vs 13.2±3.6 cm, p=.04). In multivariable regression model using pooled reader data, bronchial wall thickening exhibited odds ratio (OR) of 4.6 (95% CI: 1.3, 16.5; p=.02); pericardial effusion, OR 5.1 (95% CI: 1.7, 15.5; p=.004); pulmonary artery diameter, OR 1.4 (95% CI: 0.7, 3.0; p=.32); mean lung height, OR 0.8 (95% CI: 0.7, 1.001; p=.05); anteroposterior chest diameter, OR 1.2 (95% CI: 1.013, 1.4; p=.03). Conclusion: CT features are associated with the need for postoperative mechanical ventilation following abdominal or pelvic surgery. Clinical Impact: Many patients undergo thoracic CT before abdominal or pelvic surgery; the CT findings may complement preoperative clinical risk factors.