Right main pulmonary artery distensibility on dynamic ventilation CT and its association with respiratory function.

BACKGROUND: Heartbeat-based cross-sectional area (CSA) changes in the right main pulmonary artery (MPA), which reflects its distensibility associated with pulmonary hypertension, can be measured using dynamic ventilation computed tomography (DVCT) in patients with and without chronic obstructive pulmonary disease (COPD) during respiratory dynamics. We investigated the relationship between MPA distensibility (MPAD) and respiratory function and how heartbeat-based CSA is related to spirometry, mean lung density (MLD), and patient characteristics. METHODS: We retrospectively analyzed DVCT performed preoperatively in 37 patients (20 female and 17 males) with lung cancer aged 70.6 ± 7.9 years (mean ± standard deviation), 18 with COPD and 19 without. MPA-CSA was separated into respiratory and heartbeat waves by discrete Fourier transformation. For the cardiac pulse-derived waves, CSA change (CSAC) and CSA change ratio (CSACR) were calculated separately during inhalation and exhalation. Spearman rank correlation was computed. RESULT: In the group without COPD as well as all cases, CSACR exhalation was inversely correlated with percent residual lung volume (%RV) and RV/total lung capacity (r = -0.68, p = 0.003 and r = -0.58, p = 0.014). In contrast, in the group with COPD, CSAC inhalation was correlated with MLDmax and MLD change rate (MLDmax/MLDmin) (r = 0.54, p = 0.020 and r = 0.64, p = 0.004) as well as CSAC exhalation and CSACR exhalation. CONCLUSION: In patients with insufficient exhalation, right MPAD during exhalation was decreased. Also, in COPD patients with insufficient exhalation, right MPAD was reduced during inhalation as well as exhalation, which implied that exhalation impairment is a contributing factor to pulmonary hypertension complicated with COPD. RELEVANCE STATEMENT: Assessment of MPAD in different respiratory phases on DVCT has the potential to be utilized as a non-invasive assessment for pulmonary hypertension due to lung disease and/or hypoxia and elucidation of its pathogenesis. KEY POINTS: • There are no previous studies analyzing all respiratory phases of right main pulmonary artery distensibility (MPAD). • Patients with exhalation impairment decreased their right MPAD. • Analysis of MPAD on dynamic ventilation computed tomography contributes to understanding the pathogenesis of pulmonary hypertension due to lung disease and/or hypoxia in patients with expiratory impairment.

Association of Respiratory Functional Indices and Smoking with Pleural Movement and Mean Lung Density Assessed Using Four-Dimensional Dynamic-Ventilation Computed Tomography in Smokers and Patients with COPD.

Purpose: To correlate the ratio of the non-dependent to dependent aspects of the maximal pleural movement vector (MPMVND/D) and gravity-oriented collapse ratio (GCRND/D), and the mean lung field density (MLD) obtained using four-dimensional (4D) dynamic-ventilation computed tomography (DVCT) with airflow limitation parameters and the Brinkman index. Materials and Methods: Forty-seven patients, including 22 patients with COPD, 13 non-COPD smokers, and 12 non-smokers, with no/slight pleural adhesion confirmed using a thoracoscope, underwent 4D-DVCT with 16 cm coverage. Coordinates for the lung field center, as well as ventral and dorsal pleural points, set on the central trans-axial levels in the median and para-median sagittal planes at end-inspiration, were automatically measured (13-17 frame images, 0.35 seconds/frame). MPMVND/D and GCRND/D were calculated based on MPMV and GCR values for all the included points and the lung field center. MLD was automatically measured in each of the time frames, and the maximal change ratio of MLD (MLDCR) was calculated. These measured values were compared among COPD patients, non-COPD smokers, and non-smokers, and were correlated with the Brinkman index, FEV1/FVC, FEV1 predicted, RV/TLC, and FEF25-75% using Spearman's rank coefficients. Results: MPMVND/D was highest in non-smokers (0.819±0.464), followed by non-COPD smokers (0.405±0.131) and patients with COPD (-0.219±0.900). GCRND/D in non-smokers (1.003±1.384) was higher than that in patients with COPD (-0.164±1.199). MLDCR in non-COPD smokers (0.105±0.028) was higher than that in patients with COPD (0.078±0.027). MPMVND/D showed positive correlations with FEV1 predicted (r=0.397, p=0.006), FEV1/FVC (r=0.501, p<0.001), and FEF25-75% (r=0.368, p=0.012). GCRND/D also demonstrated positive correlations with FEV1 (r=0.397, p=0.006), FEV1/FVC (r=0.445, p=0.002), and FEF25-75% (r=0.371, p=0.011). MPMVND/D showed a negative correlation with the Brinkman index (r=-0.398, p=0.006). Conclusion: We demonstrated that reduced MPMVND/D and GCRND/D were associated with respiratory functional indices, in addition to a negative association of MPMVND/D with the Brinkman index, which should be recognized when assessing local pleural adhesion on DVCT, especially for ventral pleural aspects.

Impact of thoracic esophageal displacement after lobectomy on the continuity of oral adjuvant chemotherapy.

BACKGROUND: Adjuvant tegafur-uracil therapy has prolonged postoperative survival in patients with non-small cell lung cancer. Some patients experience treatment discontinuation due to gastrointestinal disorders such as anorexia, and the associated factors and the impact of lobectomy remain unclear. This study aimed to assess the postoperative esophageal displacement after lobectomy and to clarify its impact on the continuity of tegafur-uracil treatment. METHODS: Patients who received adjuvant tegafur-uracil therapy after lobectomy between April 2009 and March 2019 were retrospectively analyzed. Patient background, perioperative characteristics, treatment findings, and the degree of esophageal displacement measured by computed tomography were compared between the treatment completion group and the discontinuation group. A subgroup comparative analysis was further performed in the groups divided according to the degree of esophageal displacement. RESULTS: A total of 68 patients were reviewed, including 41 males and 27 females with a mean age of 66.2 years old. A total of 41 patients completed the 2-year adjuvant treatment and 27 patients discontinued it. The overall survival and relapse-free survival between the two groups were statistically significant (p = 0.027, p = 0.010). The degree of esophageal displacement at the Th7 level was a significant predictor of treatment discontinuation (p = 0.046, odds ratio [OR]: 1.138, 95% confidence interval [CI]: 1.002-1.291). Among the patients with a high degree of esophageal displacement above the baseline determined from the receiver operating characteristic curve, the cause of discontinuation was anorexia, which was significant in multivariate analysis (p = 0.013, OR: 14.72, 95% CI: 1.745-124.2). CONCLUSIONS: Our study suggested that anatomical displacement of the esophagus after lobectomy may affect the discontinuation of oral adjuvant chemotherapy in patients with lung cancer.

Perioperative changes in respiratory impedance in lobectomy and their clinical impact.

BACKGROUND: Respiratory function declines after lung resection. However, perioperative changes in respiratory impedance and their clinical significance are unclear. The forced oscillation technique can measure respiratory impedance during quiet breathing and possibly early after surgery. We investigated respiratory impedance changes before and after lung lobectomy and examined the correlation of impedance with clinical factors. METHODS: We prospectively included patients who underwent lobectomy between February 2018 and March 2020 and measured respiratory impedance by forced oscillation preoperatively and postoperative days 1 and 7. We statistically analyzed changes in perioperative forced oscillation measurements and their correlation with clinical factors, including subjective symptoms. The modified British Medical Research Council scale and the chronic obstructive pulmonary disease (COPD) assessment test were used for scoring subjective symptoms. RESULTS: Forty-four subjects were included, in whom respiratory impedance could be measured from postoperative day 1. The respective mean values for forced oscillation measurements preoperatively and at postoperative days 1 and 7 were as follows: respiratory resistance, 5 Hz: 2.28, 2.77, and 2.75; respiratory resistance, 20 Hz: 2.00, 2.36, and 2.32; difference in respiratory resistance at 5 and 20 Hz: 0.28, 0.40, and 0.43; respiratory reactance, 5 Hz: -0.31, -0.65, and -0.56; resonant frequency: 7.45, 10.41, and 9.81; and low-frequency reactance area: 1.33, 3.27, and 2.84. These changes were statistically significant (P<0.01). Besides the difference in respiratory resistance at 5 and 20 Hz, all other measurements on postoperative day 7 were relatively weakly correlated with the modified Medical Research Council scale score at this time point (all P<0.05). Respiratory complications correlated with the respiratory resistance difference, respiratory reactance, and resonant frequency on day 7 (R =0.415, -0.421, and 0.441), while the latter also correlated with postoperative hypoxemia on day 1 (R =0.433). CONCLUSIONS: Respiratory impedance was measurable even early after surgery and significantly changed postoperatively. As the sample size was small and appeared to be biased, assessing respiratory impedance and clinical factors in detail was difficult. Since respiratory impedance is suggested to be associated with clinical factors that affect the postoperative course, it is necessary to accumulate cases and observe them over longer periods.

Usability of the lateral decubitus position on four-dimensional ultra-low-dose computed tomography for the detection of localized pleural adhesion in the pulmonary apical region.

BACKGROUND: Localized pleural adhesion (LPA) evaluation in the apical region is difficult even with four-dimensional ultra-low-dose computed tomography (4D-ULDCT) in the supine position due to smaller pleural movements. PURPOSE: To assess usability of 4D-ULDCT in the lateral decubitus (LD) position for LPA detection in the apical region. MATERIAL AND METHODS: Forty-seven patients underwent 4D-ULDCT of a single respiration cycle with 16-cm coverage of body axis in supine and LD positions with the affected lung uppermost. Intraoperative thoracoscopic findings confirmed LPA presence. A pleural point and a corresponding point on costal outer edge were placed in identical axial planes at end-inspiration. Pleuro-chest wall distance between two points (PCD) was calculated at each respiratory phase. In the affected lung, average change in amount of PCD (PCDACA) was compared between patients with and without LPA in total and two sub-groups (non-COPD and COPD, non-emphysematous and emphysematous patients) in supine and non-dependent (ND) LD positions. Receiver operating characteristic (ROC) curve analysis was performed to determine optimal thresholds in PCDACA for differentiating patients with LPA from those without. RESULTS: In COPD/emphysematous patients and total population, PCDACA with LPA was smaller than in those without in the supine and NDLD positions for overall, lateral, and dorsal regions. For the lateral region in COPD patients, area under ROC curve (AUC) increased from supine (0.64) to NDLD position (0.81). For the dorsal region in emphysematous patients, AUC increased from supine (0.76) to NDLD position (0.96). CONCLUSION: 4D-ULDCT in LD position may be useful for LPA detection in apical regions for COPD and/or emphysematous patients.

Airway inflammation and lung function recovery after lobectomy in patients with primary lung cancer.

OBJECTIVE: Fractional exhaled nitric oxide (FeNO), which represents airway inflammation, is an indicator of postoperative complication after lung surgery. However, its effects in the late postoperative period are unknown. The aim of this prospective study was to clarify the impact of FeNO on postoperative lung function in patients with lung cancer. METHODS: We measured preoperative FeNO using NIOX VERO® in patients with primary lung cancer. Patients were divided into two groups according to their potential airway inflammatory status: preoperative FeNO levels below 25 ppb (N group) and above 25 ppb (H group). They were evaluated by spirometry at 3 and 6 months after surgery during follow-up. The relationship between postoperative lung function and preoperative FeNO was evaluated. RESULTS: Between September 2017 and March 2019, 61 participants were enrolled. All of them underwent lobectomy as a curative surgery. There were no significant background variables between the two groups. Postoperative vital capacity (VC) and forced expiratory volume in 1 s (FEV1) in the H group achieved less predictive values than those in the N group, which were not significant. The postoperative VC and FEV1 from 3 to 6 months in the H group were significantly increased as compared to those in the N group (p < 0.001). CONCLUSIONS: Preoperative FeNO is a predictor of delayed lung function recovery 3 months after lobectomy in lung cancer patients. The impact had extended to VC and FEV1. Although this impact is temporary, early postoperative intervention is expected to reduce the adverse effect.

[The Early Removal of the Implant after Nuss Procedure Due to the Infection in Case of Pectus Excavatum with Atopic Dermatitis].

Nuss procedure for pediatric patients with pectus excavatum has been practiced worldwide, including in Japan, due to the simple procedure and has a high therapeutic effect. Because it is usually performed under thoracoscopy to secure the safety, it is performed not only by pediatric or plastic surgeons but also by general thoracic surgeons. On the other hand, a risk of infection must always be considered in this method in which a foreign metal bar is used. In particular, when the skin barrier mechanism is declining due to skin diseases such as atopic dermatitis, the risk of infection of the implant may increase. The present case was an 8-year-old male with a history of atopic dermatitis. He underwent thoracoscopic Nuss procedure. Although there was no problem during his hospitalization, the bar was exposed from the skin on the 58th postoperative day with the infection triggered, and the unexpected early bar removal was performed on the 66th postoperative day. We report this case with some literature review.

Preoperative assessment of localized pleural adhesion: Utility of software-assisted analysis on dynamic-ventilation computed tomography.

PURPOSE: To assess the usefulness of software analysis using dynamic-ventilation CT for localized pleural adhesion (LPA). MATERIALS AND METHODS: Fifty-one patients scheduled to undergo surgery underwent both dynamic-ventilation CT and static chest CT as preoperative assessments. Five observers independently evaluated the presence and severity of LPA on a three-point scale (non, mild, and severe LPA) for 9 pleural regions (upper, middle, and lower pleural aspects on ventral, lateral, and dorsal areas) on the chest CT by three different methods by observing images from: static high-resolution CT (static image); dynamic-ventilation CT (movie image), and dynamic-ventilation CT while referring to the adhesion map (movie image with color map), which was created using research software to visualize movement differences between the lung surface and chest wall. The presence and severity of LPA was confirmed by intraoperative thoracoscopic findings. Parameters of diagnostic accuracy for LPA presence and severity were assessed among the three methods using Wilcoxon signed rank test in total and for each of the three pleural aspects. RESULTS: Mild and severe LPA were confirmed in 14 and 8 patients. Movie image with color map had higher sensitivity (56.9 ±â€¯10.7 %) and negative predictive value (NPV) (91.4 ±â€¯1.7 %) in LPA detection than both movie image and static image. Additionally, for severe LPA, detection sensitivity was the highest with movie image with color map (82.5 ±â€¯6.1 %), followed by movie image (58.8 ±â€¯17.0 %) and static image (38.8 ±â€¯13.9 %). For LPA severity, movie image with color map was similar to movie image and superior to static image in accuracy as well as underestimation and overestimation, with a mean value of 80.2 %. CONCLUSION: Software-assisted dynamic-ventilation CT may be a useful novel imaging approach to improve the detection performance of LPA.

Impact of fractional exhaled nitric oxide on the outcomes of lung resection surgery: a prospective study.

BACKGROUND: Fractional exhaled nitric oxide (FeNO), which is representative of airway inflammation, is an indicator of chronic lung disease. However, its effect on the outcome of lung resection is unknown. The aim of this prospective study was to evaluate FeNO in patients who underwent lung resection, to analyze the perioperative dynamics, and clarify the impact on postoperative complications. METHODS: We measured FeNO using NIOX VERO® once before and on days 1, 3, 5-7 after surgery in participants who were candidates for lung cancer surgery. The primary endpoint was the relationship between postoperative morbidity and preoperative FeNO. The secondary endpoint was the relationship between postoperative FeNO and additional treatment, including readmission. RESULTS: We enrolled 105 patients between September 2017 and March 2019. Anatomical lung resection was the predominant treatment (87%) for primary lung cancer. Postoperative pulmonary complications developed in 16 patients. Multivariate analysis revealed that preoperative FeNO was a significant predictor of postoperative pulmonary complications (P=0.002, OR: 1.004, 95% CI: 1.016-1.074). FeNO levels increased significantly after surgery (P=0.011). Postoperative FeNO was a significant predictor of the need for additional medical treatment within 30 days of surgery (P=0.001, OR: 1.068, 95% CI: 1.028-1.110). CONCLUSIONS: Perioperative FeNO was a significant predictor of surgical outcome among patients who underwent lung resection. The measurement of FeNO is expected to be a simple and useful method for preventing subsequent deterioration in these patients.

Continuous quantitative measurement of the main bronchial dimensions and lung density in the lateral position by four-dimensional dynamic-ventilation CT in smokers and COPD patients.

PURPOSE: The purpose of this study was to measure changes in lung density and airway dimension in smokers in the lateral position using four-dimensional dynamic-ventilation computed tomography (CT) during free breathing and to evaluate their correlations with spirometric values. MATERIALS AND METHODS: Preoperative pleural adhesion assessments included dynamic-ventilation CT of 42 smokers (including 22 patients with COPD) in the lateral position, with the unoperated lung beneath (dependent lung). The scanned lungs' mean lung density (MLD) and the bilateral main bronchi's luminal areas (Ai) were measured automatically (13-18 continuous image frames, 0.35 seconds/frame). Calculations included cross-correlation coefficients (CCCs) between the MLD and Ai time curves, and correlations between the quantitative measurements and spirometric values were evaluated by using Spearman's rank coefficient. RESULTS: The ΔMLD1.05 (from the peak inspiration frame to the third expiratory frame, 1.05 seconds later) in the nondependent lung negatively correlated with FEV1/FVC (r=-0.417, P<0.01), suggesting that large expiratory movement of the nondependent lung would compensate limited expiratory movement of the dependent lung due to COPD. The ΔAi1.05 negatively correlated with the FEV1/FVC predicted in both the lungs (r=-0.465 and -0.311, P<0.05), suggesting that early expiratory collapses of the main bronchi indicate severe airflow limitation. The CCC correlated with FEV1/FVC in the dependent lung (r=-0.474, P<0.01), suggesting that reduced synchrony between the proximal airway and lung occurs in patients with severe airflow limitation. CONCLUSION: In COPD patients, in the lateral position, the following abnormal dynamic-ventilation CT findings are associated with airflow limitation: enhanced complementary ventilation in the nondependent lung, early expiratory airway collapses, and reduced synchrony between airway and lung movements in the dependent lung.

Preoperative assessment of pleural adhesion by Four-Dimensional Ultra-Low-Dose Computed Tomography (4D-ULDCT) with Adaptive Iterative Dose Reduction using Three-Dimensional processing (AIDR-3D).

PURPOSE: To assess the feasibility of Four-Dimensional Ultra-Low-Dose Computed Tomography (4D-ULDCT) for distinguishing pleural aspects with localized pleural adhesion (LPA) from those without. METHODS: Twenty-seven patients underwent 4D-ULDCT during a single respiration with a 16cm-coverage of the body axis. The presence and severity of LPA was confirmed by their intraoperative thoracoscopic findings. A point on the pleura and a corresponding point on the outer edge of the costal bone were placed in identical axial planes at end-inspiration. The distance of the two points (PCD), traced by automatic tracking functions respectively, was calculated at each respiratory phase. The maximal and average change amounts in PCD (PCDMCA and PCDACA) were compared among 110 measurement points (MPs) without LPA, 16MPs with mild LPA and 10MPs with severe LPA in upper lung field cranial to the bronchial bifurcation (ULF), and 150MPs without LPA, 17MPs with mild LPA and 9MPs with severe LPA in lower lung field caudal to the bronchial bifurcation (LLF) using the Mann-Whitney U test. RESULTS: In the LLF, PCDACA as well as PCDMCA demonstrated a significant difference among non-LPA, mild LPA and severe LPA (18.1±9.2, 12.3±6.2 and 5.0±3.3mm) (p<0.05). Also in the ULF, PCDACA showed a significant difference among three conditions (9.2±5.5, 5.7±2.8 and 2.2±0.4mm, respectively) (p<0.05), whereas PCDMCA for mild LPA was similar to that for non-LPA (12.3±5.9 and 17.5±11.0mm). CONCLUSIONS: Four D-ULDCT could be a useful non-invasive preoperative assessment modality for the detection of the presence or severity of LPA.

Decrease in performance status after lobectomy mean poor prognosis in elderly lung cancer patients.

BACKGROUND: Surgery remains the best treatment for obtaining cure in patients with resectable lung cancer, regardless of age. In elderly patients, however, the presumed fear of decreased performance status (PS) after lobectomy has resulted in the delivery of sub-optimal cancer surgery. Surgical decision making for such patients would become easier if post-lobectomy survival benefits and changes in PS were well defined. METHODS: We reviewed patients aged 75 years or older who received lobectomy for non-small cell lung cancer (NSCLC) at our hospital between January 2004 and December 2014. Eastern Cooperative Oncology Group PS was preoperatively and postoperatively assessed in 137 patients. Patients were classified into 2 groups based on the change in PS: in Group 1, postoperative and preoperative PS were the same; in group 2, postoperative PS was less than preoperative PS. We compared the characteristics of patients in groups 1 and 2. RESULTS: Overall 5-year survival was 47.4% in group 1 and 0% in group 2 (P<0.001). History of cardiac ischemia (P=0.001) and squamous cell carcinoma (P=0.015) were identified as significant predictors of reduced postoperative PS. CONCLUSIONS: Our results show that maintenance of PS after lobectomy is expected to be associated with a good prognosis. However, reduction of PS after lobectomy indicates an extremely poor prognosis in elderly patients with lung cancer. History of cardiac ischemia and squamous cell carcinoma are possible risk factors for decreasing PS. Thus, careful patient evaluation and selection are needed when deciding whether to use lobectomy in clinical practice.

[Resection of double bronchogenic cysts within the anterior mediastinum; report of a case].

We reported a case of surgically resected double bronchogenic cysts within the anterior mediastinum. An anterior mediastinal tumor had been found at medical examination 6 years ago in a 66-year-old man, but has been followed up without treatment. After the treatment of another disease, he was referred to our hospital for evaluation of the mediastinal tumor. A chest computed tomography showed 2 anterior mediastinal nodules. Nodules in the thymus were resected with video-assisted thoracic surgery. The tumors were both pathologically diagnosed as bronchogenic cysts.