堀口 智也

BACKGROUND: We compared the capabilities of quantitatively assessed paired inspiratory-expiratory area-detector computed tomography (ADCT) for pulmonary functional loss and disease severity evaluations between upright and supine ADCT in matched progressive pulmonary fibrosis (PPF) patients. MATERIALS AND METHODS: This retrospective cohort consisted of age-, sex-, and underlying disease-matched patients with PPF who underwent paired inspiratory-expiratory CT on upright ADCT (n = 40) and supine ADCT (n = 40), pulmonary function tests, and disease severity assessment. Based on CT data, the absolute values of the logarithm of the Jacobian determinant and warp-field magnitude of the whole lung and all lobes were calculated. Stepwise regression analyses were performed. RESULTS: On supine ADCT, both indices of the left lower lobe (LLL) were the first and only steps for pulmonary function test results and CT-assessed disease severity (absolute value of the logarithm of the Jacobian determinant: 0.139 ≤ r2 ≤ 0.175, 0.007 ≤ p ≤ 0.018; absolute value of the warp-field magnitude: 0.371 ≤ r2 ≤ 0.447, p < 0.001). However, on upright ADCT, both indices indicated that LLL was the first step and the right lower lobe was the second step for pulmonary function test results and CT-assessed disease severity (0.503 ≤ r2 ≤ 0.674, p < 0.001 or 0.000 < p ≤ 0.006 and 0.474 ≤ r2 ≤ 0.652, 0.002 ≤ p ≤ 0.045, respectively). CONCLUSION: Upright ADCT has equal to or better potential than supine ADCT for detecting pulmonary functional loss and evaluating disease severity when paired inspiratory-expiratory ADCT is applied in PPF patients. RELEVANCE STATEMENT: Upright ADCT has superior potential to supine ADCT for pulmonary functional loss and disease severity evaluations when paired inspiratory-expiratory ADCT is performed in patients with progressive pulmonary fibrosis (PPF). KEY POINTS: Matched progressive pulmonary fibrosis patients compared functional loss and disease severity evaluations between inspiratory-expiratory upright and supine area-detector CT. Clinical parameters demonstrated better correlations with upright than with supine inspiratory-expiratory area-detector CT. Warp-field magnitude showed better correlations with disease severities than the logarithm of the Jacobian determinant on each area-detector CT.

INTRODUCTION: Accurate diagnosis of peripheral pulmonary lesions is crucial in respiratory medicine. Radial endobronchial ultrasound (R-EBUS), navigation technologies, and ultrathin bronchoscopes have progressively enhanced distal airway access. Mixed reality (MR) offers a hands-free method for visualizing and manipulating CT-derived three-dimensional (3D) anatomy within the operator's field of view. This retrospective study aimed to describe the technical feasibility and safety of intraprocedural MR-based holographic virtual bronchoscopy (VB) use. METHODS: This study included patients who underwent bronchoscopy for peripheral pulmonary lesions using an MR-based 3D holographic VB system. CT datasets were converted into 3D polygon models and displayed on a HoloLens 2 headset. Operators/assistants intraprocedurally referenced and manipulated the hologram while advancing the bronchoscope. Procedural variables, R-EBUS findings, biopsy techniques, diagnostic yield, and complications were evaluated. RESULTS: Eighteen patients were included. A direct bronchus sign was present in 12 lesions. The median bronchial generation that could be visualized on CT and 3D-VB was six, whereas bronchoscopy enabled advancement to a median of five generations. Radial EBUS demonstrated a within-lesion position in 13 cases. Biopsy techniques included forceps biopsy, cryobiopsy, and TBNA. The overall diagnostic yield was 72.2% (13/18), with malignant disease accounting for the majority of diagnoses. One patient developed mild pneumothorax, which resolved without drainage. CONCLUSION: MR-based holographic VB enabled real-time, hands-free 3D anatomical referencing without interrupting the procedure. Further prospective studies are warranted to assess procedural benefits and potential integration with other bronchoscopic modalities and devices.

BACKGROUND: Although bronchoscopic biopsy serves as a cornerstone for diagnosing lung cancer in elderly patients, whether this procedure leads to clinically relevant outcomes is still unclear. This study aimed to clarify the clinical significance of diagnostic bronchoscopy in lung cancer patients aged ≥80 years. METHODS: We retrospectively analyzed 803 patients diagnosed with lung cancer who underwent bronchoscopy at our hospital from April 2015 to March 2019. Those aged ≥80 years and <80 years were classified as the elderly group (n = 154) and young group (n = 649), respectively. RESULTS: The diagnostic yield of bronchoscopy in the elderly and young groups was 92.9 % and 83.5 %, respectively; complication rates were 9.6 % and 7.2 %. Approximately 89 % of the patients in the elderly group received specific lung cancer treatment. The 5-year survival rates for elderly and young patients who underwent surgery were 74.5 % and 78.2 %, respectively. In the elderly group, 11 % of the patients chose best supportive care (BSC) only, compared with 2 % in the young group. Notably, patients with non-diagnostic bronchoscopic results selected BSC more frequently in the elderly versus young groups (30.4 % versus 0 %, respectively). CONCLUSIONS: Bronchoscopy in elderly patients with lung cancer demonstrated a high diagnostic yield and an acceptable safety profile, enabling specific treatments in the majority of cases. These findings support the clinical usefulness of bronchoscopy in guiding treatment decisions for elderly patients. However, non-diagnostic results were associated with a higher likelihood of BCS, highlighting the importance of achieving a definitive diagnosis in this population.

Bronchoscopic lung volume reduction (BLVR) with endobronchial valves is an established treatment for selected patients with advanced emphysema. A 74-year-old male patient with chronic obstructive pulmonary disease and severe dyspnea was scheduled to undergo BLVR targeting the right middle lobe bronchus based on high-resolution CT findings, which showed severe emphysematous changes with hyperinflation and fissure completeness of 98% in the right middle lobe. The physician conducted preoperative virtual reality (VR)-assisted planning using the patient's imaging data, enabling comprehensive visualisation of the bronchial tree, airway measurements, and procedural simulation. The Chartis system confirmed a 'no flow' pattern, supporting the absence of collateral ventilation. During the procedure, a size 5.5 valve was placed in the right B4/5 bronchus following VR and intraoperative assessments. The patient remained stable postoperatively without complications. VR enhanced procedural planning by improving airway assessment, optimising valve sizing, and reducing cognitive load, leading to increased efficiency and operator confidence. Further research is warranted to validate the utility of VR in bronchoscopic interventions.