Target Lobe Research Articles

Lessons learned: Risk factors and clinical impact of severe pneumothorax after endoscopic lung volume reduction with endobronchial valves

BackgroundPneumothorax is a major complication following endoscopic lung volume reduction with valves with a prevalence of up to 34%. While some patients benefit from valve implantation despite pneumothorax, others are significantly impaired after lung collapse. Research questionWhat are the differences in the severity grades of pneumothorax and how does that affect our clinical practice? Study design and MethodsThis single-center retrospective study analyzed patients undergoing endoscopic valve implantation with and without post-interventional pneumothorax. Emphysema characteristics, collateral ventilation, management, and outcome of patients with pneumothorax 3 months after valve implantation were assessed. Pneumothorax was categorized as “severe pneumothorax” (chest tube insertion, prolonged air leak requiring valve removal), “moderate pneumothorax” (chest tube, no valve removal), and “mild pneumothorax” (no chest tube). ResultsPneumothorax occurred in 102/532 patients (19%) and was significantly more common after valve placement in the upper lobes (31.3%) compared to the lower lobes (11.3%, p < 0.001). Fissure integrity was significantly higher in patients with pneumothorax (mean 96.6 ± 6.3 % vs. 93.4 ± 10.3 %, p = 0.002). Of all pneumothoraces, 30.4% were mild, 30.4% moderate, 39.2% severe. Severe pneumothorax caused multiple complications and prolonged hospitalization. Valve placement in the left upper lobe and a larger size of the target lobe were identified as risk factors for severe pneumothorax. Patients with pneumothorax developed complete lobar atelectasis in >60% as a sign of therapeutic success, but obviously only when valves could be left in place or re-implanted. However, valve re-implantation resulted in re-pneumothorax in 42.9%. InterpretationPatients could be more individually informed about their risk of pneumothorax, which varies with target lobe location, fissure integrity and re-implantation. The poor outcome and high complication rate of severe pneumothorax calls for future research into the prediction of severe pneumothorax.

Role of quantitative planar lung perfusion scintigraphy and tomography in identifying target lobes in patients with emphysematous phenotype of advanced chronic obstructive pulmonary disease: a retrospective cross-sectional study.

Chronic obstructive pulmonary disease (COPD) is a common, preventable, and treatable disease. Despite optimal medical therapy and pulmonary rehabilitation, bronchoscopic and surgical lung volume reduction may still be necessary. Identifying the target lobe is crucial for the success of these treatments. This study aims to compare the role of quantitative planar lung perfusion scintigraphy (QPLPS) with quantitative lung computed tomography (StratX®), which is used in identifying the target lobe before the Zephyr® endobronchial valve (EBV) placement in patients with the emphysematous phenotype of advanced COPD. A single-center retrospective cross-sectional study was performed in the Department of Pulmonology at the University of Health Sciences Turkey, Yedikule Chest Diseases and Thoracic Surgery Education and Research Hospital between June 2019 and June 2022. The study included 46 patients with the emphysematous phenotype of advanced COPD, who were all candidates for Zephyr® EBV therapy. The target lobes were assessed using the QPLPS and StratX® and the agreement between the methods was analyzed by the Kappa statistic method. Additionally, demographic characteristics, respiratory function tests, distributions of emphysema, and 6-minute walk test results of patients were recorded. The median age was 67 (42-80) years and 42 (91.3%) were male. In QPLPS, the perfusion percentages were 7.47%±3.31%, 9.59%±2.67%, and 13.32%±2.59% for the 1st, 2nd and 3rd target lobes, respectively while in StratX®, the voxel densities were 68.28%±9.16%, 63.79%±7.42%, and 60.69%±5.35%. In StratX®, the fissure integrity (FI) at the target lobe was 76.25%±21.18%, 84.68%±17.67%, and 86.19%±13.19%, respectively. There was a significant agreement between the methods in identifying the first, second, and third target lobes in all patients (Kappa coefficient: 0.897, 0.700, and 0.522), and also in identifying the first and second target lobes in patients with heterogeneous (Kappa coefficient: 0.879, and 0.735), and homogeneous subgroups (Kappa coefficient: 0.919, and 0.672). There is an agreement between QPLPS and StratX® in identifying the target lobe in patients with severe emphysema, including those with homogeneous diseases. However, StratX® may be preferred, considering that it also predicts FI.

First real-time imaging of bronchoscopic lung volume reduction by electrical impedance tomography

BackgroundBronchoscopic lung volume reduction (BLVR) with one-way endobronchial valves (EBV) has better outcomes when the target lobe has poor collateral ventilation, resulting in complete lobe atelectasis. High-inspired oxygen fraction (FIO2) promotes atelectasis through faster gas absorption after airway occlusion, but its application during BLVR with EBV has been poorly understood. We aimed to investigate the real-time effects of FIO2 on regional lung volumes and regional ventilation/perfusion by electrical impedance tomography (EIT) during BLVR with EBV.MethodsSix piglets were submitted to left lower lobe occlusion by a balloon-catheter and EBV valves with FIO2 0.5 and 1.0. Regional end-expiratory lung impedances (EELI) and regional ventilation/perfusion were monitored. Local pocket pressure measurements were obtained (balloon occlusion method). One animal underwent simultaneous acquisitions of computed tomography (CT) and EIT. Regions-of-interest (ROIs) were right and left hemithoraces.ResultsFollowing balloon occlusion, a steep decrease in left ROI-EELI with FIO2 1.0 occurred, 3-fold greater than with 0.5 (p < 0.001). Higher FIO2 also enhanced the final volume reduction (ROI-EELI) achieved by each valve (p < 0.01). CT analysis confirmed the denser atelectasis and greater volume reduction achieved by higher FIO2 (1.0) during balloon occlusion or during valve placement. CT and pocket pressure data agreed well with EIT findings, indicating greater strain redistribution with higher FIO2.ConclusionsEIT demonstrated in real-time a faster and more complete volume reduction in the occluded lung regions under high FIO2 (1.0), as compared to 0.5. Immediate changes in the ventilation and perfusion of ipsilateral non-target lung regions were also detected, providing better estimates of the full impact of each valve in place.Trial registrationNot applicable.

The Diagnostic Efficiency and Safety of Transbronchial Lung Cryobiopsy Using 1.1-mm Cryoprobe in Diagnosing Interstitial Lung Disease.

Transbronchial lung cryobiopsy (TBLC) is increasingly used to diagnose interstitial lung disease (ILD). The 1.1-mm cryoprobe has recently been available in clinical practice. The diagnostic yield and safety of TBLC using a 1.1-mm cryoprobe need to be confirmed. A prospective, randomized controlled trial was conducted in patients with suspected ILD and randomly assigned to 1.1-mm and 1.9-mm cryoprobe groups. The primary outcome was the diagnostic yield of multidisciplinary discussion. Secondary outcomes were sample quality and incidence of complications. The tension and stress effects during TBLC onto the target lobe caused by 1.1-mm and 1.9-mm cryoprobes were also evaluated using finite element analysis. A total of 224 patients were enrolled. No significant differences were observed in the diagnostic yield (80.4% vs. 79.5%, p = 0.845) and sample quality scores (5.73 ± 0.64 vs. 5.66 ± 0.77; p = 0.324) between the 1.9-mm cryoprobe group and 1.1-mm cryoprobe group. The average surface areas of samples in 1.1-mm cryoprobe group were smaller, while no difference in sample weights was observed. A decreased incidence of moderate bleeding was found in the 1.1-mm cryoprobe group (17.0% vs. 6.2%, p = 0.027), while there was no difference in the incidence of the pneumothorax, there was a trend to higher rate of pneumothorax in 1.1-mm group. In finite element analysis, the 1.1-mm cryoprobe required the largest tension and produced the largest stress. Compared with a 1.9-mm cryoprobe, there was no difference in specimen quality or diagnostic rate but smaller sample size with a 1.1-mm cryoprobe. There was a decreased risk of moderate bleeding, but a trend towards increased risk for pneumothorax with 1.1-mm cryoprobe. Clinicaltrials.gov identifier NCT04047667; registered August 4, 2019.

Quantitative lobar Tc99m-MAA SPECT/CT of the lung in pre-and post-procedural guidance for bronchoscopic lung volume reduction.

This prospective study included 92 patients who underwent BLVR with quantitative SPECT/CT study pre- and post-procedure between November 2018 and June 2023. The mean age was 70 years (range 56-85). with 51 males and 41 females. SPECT/CT quantified perfusion for each lobe, and the lowest counts/volume ratio determined the procedural target. Postprocedure SPECT/CT assessed total atelectasis and perfusion shifts. The 6-minute walk test and pulmonary function tests were compared pre- and post-BLVR. SPECT/CT-guided BLVR showed clinical benefits (decreased oxygen requirements) and physiological improvements in total lung capacity, forced expiratory volume, and forced vital capacity ( P < 0.05). Significant perfusion shifts were observed away from the target lobe, with unique patterns noted for ipsilateral and contralateral nontarget lobes ( P < 0.05). Quantitative lobar SPECT/CT in preprocedural guidance for BLVR proved useful in identifying suitable targets in multi-lobe homogeneous emphysema, resulting in physiological and clinical improvements for this patient group. The perfusion shift information provided by SPECT/CT offers valuable insights for pulmonologists.

Impact of Bronchoscopic Lung Volume Reduction with Valves on the Pulmonary Gas Exchange.

Introduction: Bronchoscopic lung volume reduction (BLVR) with endobronchial valves has been shown to be a safe and effective treatment for patients with severe lung emphysema. Previous studies have reported a benefit in pulmonary function, exercise capacity, and quality of life after BLVR-treatment. The effect of BLVR with valves on the pulmonary gas exchange and its association with clinical outcomes has not been analyzed to date. The primary goal of this study was to investigate the impact of BLVR on the pulmonary gas exchange and the impact of the target lobe selection in patients with discordant target lobes in high-resolution computed tomography (HRCT) scan and perfusion scan on the pulmonary gas exchange and clinical outcomes. Methods: In this single-center study, we retrospectively analyzed pulmonary function tests, 6-min-walk-tests, HRCT scans, perfusion scans, and blood gas analyses in 77 patients over the course of 6 months following BLVR treatment. Results: We observed that complete lobar occlusion with bronchoscopic valves leads to a transient impairment of pulmonary gas exchange. Despite this, an overall positive clinical outcome could be shown in patients treated with endobronchial valves. If the target lobe selection based on HRCT and perfusion scans is discrepant, a selection based on the HRCT scan tends to be associated with a better outcome than a selection based on the perfusion scan. Conclusions: Complete lobar occlusion with bronchoscopic valves leads to a transient impairment of pulmonary gas exchange but nevertheless results in an overall positive clinical outcome.

Efficacy and safety of the Spiration Valve System™ for the treatment of severe emphysema in patients with Alpha-1 antitrypsin deficiency (EMPROVE)

ObjectivesAlpha-1 antitrypsin deficiency (AATD) is a hereditary condition associated with emphysema. This study analyzed the efficacy and safety of Spiration Valve System TM (SVS) among AATD patients with severe emphysema. MethodsThis multicenter prospective study included 20 patients demonstrating AATD as assessed by quantitative levels of AAT and genotype containing two ZZ alleles. Most diseased lobe based on high resolution computed tomography was selected for treatment with endobronchial SVS. The change from baseline in forced expiratory volume in 1 s (FEV1) at 6 months (Primary outcome) and at 12 months, quality-of-life (QoL) measured by St. George's Respiratory Questionnaire (SGRQ) as health status, dyspnea scale measured by mMRC, Chronic obstructive pulmonary disease (COPD) Assessment Test (CAT), 36-item Short Form Health Survey (SF-36) physical component summary (PCS) and safety were assessed. ResultsLung function (FEV1) significantly improved at 6 months (P = 0.02); but did not reach statistical significance at 12 months (P = 0.22). Significant improvement was observed in dyspnea (at all time points), QoL measures (3, 6, and 12 months), CAT score and PCS of SF-36 (1, 3 and 6 months). Response rates based on minimal clinically important difference reached 50–80% for all variables. Overall, 4.4 valves/patient were used to isolate the target lobe, with a mean procedure time of 20.3 min. Serious adverse events included COPD exacerbations (5%), pneumonia (10%), pneumothorax (15%) and death (5%), occurring within first three months. ConclusionSVS endobronchial valve treatment showed improvement in lung function, dyspnea, and QoL in AATD patients with severe emphysema.

A Quantitative Computed Tomography Analysis of Fissure Integrity and Emphysema Destruction in Japanese Patients with Severe Chronic Obstructive Pulmonary Disease.

Objective Bronchoscopic lung volume reduction (BLVR) using a one-way endobronchial valve (EBV) can provide clinically meaningful benefits to chronic obstructive pulmonary disease (COPD) patients. Although the Japanese Pharmaceuticals and Medical Devices Agency approved EBVs in November 2022, information regarding the number of Japanese patients with severe COPD eligible for BLVR treatment is still lacking. We therefore screened computed tomography (CT) images of patients with severe COPD using a quantitative CT (QCT) analysis to estimate the proportion of candidates eligible for BLVR treatment with an EBV. Methods CT scans of COPD patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages 3 and 4 were retrospectively analyzed using QCT to evaluate fissure integrity and tissue destruction. The difference in volume-weighted percentage was measured using the density scores of the target lobe and ipsilateral non-target lobe at -910 Hounsfield units. The target lobe was defined as the most affected lobe, with an emphysema destruction score of >50% for each patient. Results High-resolution CT scans of 32 patients (GOLD 3=19, GOLD 4=13) were analyzed. The target lobe could not be identified in 1 patient, whereas the target lobes for 8 patients were not surrounded by fissures with ≥80% completeness. Conversely, in 13 patients, the target lobes were surrounded by fissures with >95% completeness. The remaining 10 patients had fissure completeness between 80% and 95% at the target lobes and were considered candidates for collateral ventilation assessment. Conclusion A QCT analysis showed that 23 of 32 patients with severe COPD could be considered for a thorough examination of BLVR treatment with EBV.

Bronchoscopic Lung Volume Reduction: Highlighting the Patient Selection Process

Patients with advanced emphysema frequently experience severe dyspnea that is inadequately treated with medical therapy alone. Over the past 4 years, we have seen increased usage of bronchoscopic lung volume reduction (BLVR) with endobronchial valves. Success of the procedure is dependent on patient selection because it is not necessarily appropriate for all patients with severe emphysema. (Table 1) The purpose of this review is to highlight the selection process at a single institution. We also discuss the influence of this process on outcomes. Between March 1, 2019, and October 12, 2021, 2402 patients were referred to a dedicated chronic obstructive pulmonary disease clinic at Mayo Clinic – Rochester, whereas 161 patients were subsequently referred for multidisciplinary BLVR review. Of those patients, 53 (32.9%) were selected to receive valves and 35 (21.7%) ultimately underwent the procedure. The main reasons for exclusion included an incompatible quantitative computed tomography analysis (n=37, 34.3%), presence of pulmonary nodule or active malignancy (n=14, 13.0%), or need for completion of pulmonary rehabilitation (n=9, 8.3%). Full or partial (>70%) target lobe collapse was observed in 58.6% of patients who received valves. Those with collapse experienced statistically significant improvements in spirometric measures. Twelve patients experienced a pneumothorax (34.3%), with 10 patients requiring thoracostomy tube placement and prolonged hospitalization (median, 11 days; range, 4-39 days). Nineteen patients required a secondary procedure within the first year. The study highlights how a multidisciplinary approach to the BLVR selection process enables individualization of a complex procedure and enhances the exclusion of inappropriate candidates.

The impact of emphysema heterogeneity on treatment response after endobronchial valve treatment.

Lung volume reduction with endobronchial valves can significantly improve functional outcomes in patients with advanced emphysema. The extent and spatial distribution pattern of emphysema shows considerable heterogeneity, which might affect response to endobronchial valve treatment. Our aim was to study the effect of emphysema heterogeneity on change in clinical outcomes after endobronchial valve treatment. Data were collected from our national registry of patients who received endobronchial valve treatment between 2016 and 2020. We assessed the association between the heterogeneity index, absolute difference in destruction between the target and ipsilateral lobe, and relative change in forced expiratory volume in 1 s (FEV1), residual volume (RV), St George's Respiratory Questionnaire (SGRQ) and 6-min walk distance (6MWD) at 6-week, 6-month and 12-month follow-up. In total, 236 patients were included. Heterogeneity index was significantly associated with improvements in FEV1, RV and 6MWD at all follow-up visits, and in SGRQ at the 6- and 12-month follow-up visits. The majority of patients, independent of heterogeneity index, showed clinically meaningful improvements based on minimal important difference thresholds. Heterogeneity index influences the degree of clinical improvement after endobronchial valve treatment where in general a more heterogeneous distribution translates to larger improvements. However, patients with a more homogeneous distribution also showed clinically meaningful improvements. Therefore, we believe emphysema heterogeneity alone should not be used as a decisive patient selection criterion, but should be weighed in the context of all other relevant patient and target lobe characteristics when deciding on a patient's treatment eligibility.

Lung Volume Reduction in Patients with Severe Emphysema: Bronchoscopic Lobar versus Surgical Tailored Treatment

Abstract Background Bronchoscopic lung volume reduction (BLVR) with valves excludes one whole lobe while lung volume reduction surgery (LVRS) allows tailored treatment by resection of only heterogeneous, hardly perfused target areas. Aims We hypothesize that by (bilateral) LVRS, more areas of low attenuation (LAA, ≤ - 950 houndsfield units) can be resected more precisely, thus generating more functional improvement than BLVR. Methods Empysema patients treated with BLVR and LVRS at our institution between August 2019 and October 2020 were collected prospectively and analyzed retrospectively. LVRS responders were defined as patients with a postoperative improvement of at least 10% in FEV1 in combination with 10% delta in 6-minute-walking-distance (6MWD) or residual volume (RV) or diffusion capacity (DLCO), within the BLVR group additionally with a chest CT scan proven target lobe atelectasis. We performed LAA measurement in preoperative CT scan and 3 months (LVRS) or 1 month (BLVR) postoperatively. Functional improvement as well as LAA reduction was measured in each group and the groups compared with each other. Results 29 patients underwent LVRS, 19 were responders (5 bilateral LVRS, 14 unilateral), 3 were lost for follow up. Within the BLVR group (n=29), 18 were responders. In bilateral LVRS, improvement of 6MWD and FEV1 was significantly higher than in BLVR, accompanied by a significantly higher LAA-reduction (22.18 vs 9.54, p=0.009). In unilateral LVRS, LAA-reduction was not significantly higher (12.06 vs 9.54, p=0.267), while 6MWD and FEV1 still showed a higher postoperative improvement. RV reduction and DLCO improvement did not differ significantly between the groups. Conclusions LVRS might lead to significantly more functional improvement than BLVR with valves, maybe due to more resected LAA, especially in bilateral surgery. This concept may justify favoring primary bilateral LVRS over BLVR with valves in bilateral heterogeneous emphysema.

Response to endobronchial valve treatment: it's all about the target lobe.

Bronchoscopic lung volume reduction using endobronchial valves (EBV) has been shown to be beneficial for severe emphysema patients. The most important predictor of treatment response is absence of collateral ventilation between the treatment target and ipsilateral lobe. However, there are still a substantial number of nonresponders and it would be useful to improve the pre-treatment identification of responders. Presumably, predictors of response will be multifactorial, and therefore our aim was to explore whether we can identify response groups using a cluster analysis. At baseline and 1 year follow-up, pulmonary function, exercise capacity and quality of life were measured. A quantitative chest computed tomography scan analysis was performed at baseline and 2-6 months follow-up. The cluster analysis was performed using a hierarchical agglomerative method. In total, 428 patients (69% female, mean±sd age 61±8 years, forced expiratory volume in 1 s 27±8% predicted, residual volume 254±50% pred) were included in our analysis. Three clusters were generated: one nonresponder cluster and two responder clusters. Despite solid technical procedures, the nonresponder cluster had significantly less clinical response after treatment compared to the other clusters. The nonresponder cluster was characterised by significantly less emphysematous destruction, less air trapping and a higher perfusion of the target lobe, and a more homogeneous distribution of emphysema and perfusion between the target and ipsilateral lobe. We found that target lobe characteristics are the discriminators between responders and nonresponders, which underlines the importance of visual and quantitative assessment of the potential treatment target lobe when selecting patients for EBV treatment.

Validation of RAH VQ SPECT/CT lobar quantification program using a modified version of GE Q lung.

The value of ventilation-perfusion (VQ) single photon emission tomography/computed tomography (SPECT/CT) lobar quantification for pre-operative assessment of lobectomy and lung volume reduction is known. Our in-house developed software, RAH ventilation perfusion SPECT/CT quantification (RAHVQSQ) has been shown to be able to identify the target lobe for collapse in bronchoscopic lung volume reduction (BLVR) for advanced emphysema. We have proven inter and intra observer reproducibility but are yet to validate the accuracy of our program. This study aims to validate the accuracy of our quantitative program through comparison with a modified version of GE Q lung which is a commercial program certified for clinical use. Ventilation-perfusion SPECT/CT data of 19 subjects from our previous study using RAHVQSQ for BLVR assessment were re-analysed using Q lung by 2 technologists independently and in a blinded fashion to determine lobar differential ventilation, perfusion and volume percentages. The data were from GE Hawkeye 4 and external CT, thus a modified version of Q lung was used. To determine interobserver variation in the 3 parameters between the 3 assessors, intraclass correlation coefficient (ICC) and Bland-Altman limits of agreement (LoA) were generated. Paired comparisons between the 3 assessors had high ICC (range for ventilation: 0.69-0.97; perfusion: 0.69-0.97; volume: 0.63-0.97) and means of LoA differences close to zero (range for ventilation: -0.04 - 0.10; perfusion: 0.00-0.02; volume: -0.12 - 0.09) were noted indicative of good concordance for all parameters. Using VQ SPECT/CT data of participants with advanced airway disease, our study has found a close concordance of estimated differential lobar ventilation, perfusion and volume percentages using RAHVQSQ when compared with a duplicated blinded assessment using Q lung. The good concordance supports the validity of our quantitative methodology.

Impact of bronchoscopic lung volume reduction with endobronchial valves on dynamic hyperinflation: Results from the PIERCE study.

Dynamic hyperinflation (DH) is a major marker of exertional dyspnoea in severe emphysema. We hypothesized that bronchoscopic lung volume reduction (BLVR) using endobronchial valves (EBVs) decreases DH. In this prospective bi-centre study from both Toulouse and Limoges Hospitals, we assessed DH during an incremental cycle ergometry before and 3months after EBVs treatment. The primary objective was to observe the change in inspiratory capacity (IC) at isotime. Target lobe volume reduction (TLVR) and changes in residual volume (RV), forced expiratory volume in one-second (FEV1 ), mMRC, 6minutes walking distance (6MWD), BODE and other dynamic measures like tele-expiratory volume (EELV) were also analysed. Thirty-nine patients were included, of whom thirty-eight presented DH. IC and EELV at isotime significantly improved (+214 mL, p= 0.004; -713 mL, p˂0.001, respectively). Mean changes were +177 mL for FEV1 (+19%, p< 0.001), -600 mL for RV (p< 0.0001), +33 m for 6MWD (p< 0.0001), respectively. Patients who responded on RV (>430 mL decrease) and FEV1 (>12% gain) had better improvements compared to non-responders (+368 mL vs. +2mL; +398 mL vs. -40 mL IC isotime, respectively). On the opposite, in patients who responded on DH (>200 mL IC isotime increase), changes in TLV (-1216 mL vs. -576 mL), FEV1 (+261 mL vs. +101 mL), FVC (+496 mL vs. +128 mL) and RV (-805 mL vs. -418 mL) were greater compared to non-responders. DH decreases after EBVs treatment, and this improvement is correlated with static changes.

Improved exercise capacity results in a survival benefit after endobronchial valve treatment

BackgroundBronchoscopic lung volume reduction using endobronchial valves (EBV) is a treatment option for selected patients with advanced emphysema. The treatment significantly improves pulmonary function, exercise capacity, quality of life, and potentially improves survival. Our main aim was to assess whether treatment response significantly influences survival time after EBV treatment. MethodsWe evaluated treatment response at 6-week and 1-year follow-up of all patients treated with EBVs between 2008 and 2020. Survival status was retrieved on December 1, 2021. Patients were defined as responders or non-responders based on known minimal important differences for FEV1, residual volume (RV), RV/Total Lung Capacity (TLC) ratio, 6-min walk distance (6MWD), St. George's Respiratory Questionnaire (SGRQ), target lobe volume reduction (TLVR), and complete lobar atelectasis. Uni- and multivariate cox regression models were used to evaluate the effect of response on survival time. ResultsA total of 428 patients were included. EBV treatment resulted in significant improvements in pulmonary function, exercise capacity and quality of life. Median survival was 8.2 years after treatment. SGRQ and 6MWD response were independent predictors for improved survival time (Hazard Ratio (HR) 0.50 [0.28–0.89], p = .02 and HR 0.54 [0.30–0.94], p = .03, respectively). The presence of a complete lobar atelectasis did not significantly affect survival, neither did pulmonary function improvements. ConclusionsOur results suggest that improvement in exercise capacity and quality of life after EBV treatment are associated with a survival benefit, independent of improvements in pulmonary function, reduction in target lobe volume or the presence of complete lobar atelectasis.

Initial Report on Liver Reirradiation with Proton Beam Therapy after 90Y Transarterial Chemoembolization

<h3>Purpose/Objective(s)</h3> With the increasing use of proton beam therapy (PBT) in treatment of hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA), and other cancers involving the liver, there is a growing need to determine treatment-related toxicity, particularly when used as re-treatment. There is limited safety and efficacy data on re-treatment with PBT after Transarterial Radioembolization (TARE). This study evaluates safety of PBT use in patients who received PBT following previous TARE for liver-related cancer. <h3>Materials/Methods</h3> A single center retrospective study identified 12 patients with liver-related cancers who received PBT after initial treatment with TARE between 2014 – 2020. Patient-related toxicity was assessed using Child-Turcott-Pugh (CTP) Scores and the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Secondary endpoints were overall survival (OS), progression-free survival (PFS), and Local control (LC). <h3>Results</h3> All patients received microsphere-based ⁹⁰Y TARE with a median dose of 150 Gy (range, 120 - 150 Gy) prescribed to the target lobe. Of the included patients, seven (58%) had hepatocellular carcinoma, three (25%) had metastatic disease, and two (17%) had intrahepatic cholangiocarcinoma. Prior to TARE median CTP score was A6 (range A5-B7). Median time to initial failure was 5.6 months (range 2.4 - 47.7 months) with seven (58%) local failures at site of TARE. Median CTV volume for PBT was 493ccs (range 104 – 1395ccs). Ten patients (83%) received 5805CGE in 15 fractions and two patients (17%) received 5000CGE in 5 fractions. No patients had a decline in CTP score greater than 1 point with a median CTP A6 (range A5 – B8). There were no CTCAE grade 3+ acute or late toxicities. Median follow-up after PBT was 12.7 months and median OS was 12.5 months (95% CI, 8.8 - 16.2 months) and PFS was 9.0 months (95% CI, 6.5 – 12.4 months). No patients had local failure, while two had liver failure, and eight had distant metastatic failure. <h3>Conclusion</h3> Use of PBT as re-treatment following ⁹⁰Y TARE appears to be well-tolerated and safe in an early evaluation for patients with definitive doses. Larger, multi-institutional studies are needed to verify this evaluation.

The Role of 18F-FLT PET/CT in Assessing Early Response to Transarterial Radioembolization and Chemoembolization in Patients with Primary and Metastatic Liver Tumors.

Objectives:Metastases and primary malignancies are common in the liver. Local ablative applications such as transarterial chemoembolization (TACE), and transarterial radioembolization (TARE) provide minimally invasive and safe treatment in unresectable liver tumors. Early detection of response to treatment prevents unnecessary toxicity and cost in non-responder patients and provides an earlier use of other options that may be effective. This study aimed to identify the role of 18F-fluorothymidine (FLT) positron emission tomography/computed tomography (PET/CT) in the assessment of early response to TACE and TARE treatments in patients with unresectable primary and metastatic liver tumorsMethods:This single-center study included 63 patients who underwent 18F-FLT PET/CT for response evaluation after TACE and TARE. After excluding 20 patients whose data were missing 43 TARE-receiving patients were analyzed. The compatibility of change in semi-quantitative values obtained from the 18F-FLT PET/CT images with the treatment responses detected in 18F-fluorodeoxyglucose PET/CT, CT, and MR images and survival was evaluated.Results:There was no correlation between early metabolic, morphological response, and 18F-FLT uptake pattern, and change in standardized uptake values (SUV) which were ΔSUVmax, ΔSUVmean, ΔSUVpeak., ΔSUVmean, Δ SUVpeak values. There was no significant correlation between 18F-FLT uptake pattern, ΔSUVmax, ΔSUVmean, ΔSUVpeak, and overall survival, progression-free survival (PFS) for the target lobe PFS for the whole-body. The survival distributions for the patients with >30% change in Δ SUVmax and ΔSUVpeak values were statistically significantly longer than the patients with <30% change (p<0.009 and p<0.024, respectively).Conclusion:There was significant longer PFS for target liver lobe in patients with more than 30% decrease in 18F-FLT SUVmax and SUVpeak of the liver lesion in primary and metastatic unresectable liver tumors undergoing TARE.

When Treatment of Pulmonary Emphysema with Endobronchial Valves Did Not Work: Evaluation of Quantitative CT Analysis and Pulmonary Function Tests Before and After Valve Explantation.

PurposeTo investigate changes in quantitative CT analysis (QCT) and pulmonary function tests (PFT) in pulmonary emphysema patients who required premature removal of endobronchial valves (EBV).Patients and MethodsOur hospital’s medical records listed 274 patients with high-grade COPD (GOLD stages 3 and 4) and pulmonary emphysema who were treated with EBV to reduce lung volume. Prior to intervention, a complete evaluation was performed that included quantitative computed tomography analysis (QCT) of scans acquired at full inspiration and full expiration, pulmonary function tests (PFT), and paraclinical findings (6-minute walking distance test (6MWDT) and quality of life questionnaires). In 41 of these 274 patients, EBV treatment was unsuccessful and the valves had to be removed for various reasons. A total of 10 of these 41 patients ventured a second attempt at EBV therapy and underwent complete reevaluation. In our retrospective study, results from three time points were compared: Before EBV implantation (BL), after EBV implantation (TP2), and after EBV explantation (TP3). QCT parameters included lung volume, total emphysema score (TES, ie, the emphysema index) and the 15th percentile of lung attenuation (P15) for the whole lung and each lobe separately. Differences in these parameters between inspiration and expiration were calculated (Vol. Diff (%), TES Diff (%), P15 Diff (%)). The results of PFT and further clinical tests were taken from the patient’s records.ResultsWe found persistent therapy effect in the target lobe even after valve explantation together with a compensatory hyperinflation of the rest of the lung. As a result of these two divergent effects, the volume of the total lung remained rather constant. Furthermore, there was a slight deterioration of the emphysema score for the whole lung, whereas the TES of the target lobe persistently improved.ConclusionInterestingly, we found evidence that, contrary to our expectations, unsuccessful EBV therapy can have a persistent positive effect on target lobe QCT scores.

INITIAL EXPERIENCE WITH INTRAPROCEDURAL ELECTRICAL IMPEDANCE TOMOGRAPHY FOR EVALUATING REGIONAL VENTILATION CHANGES DURING BRONCHOSCOPIC LUNG VOLUME REDUCTION

INITIAL EXPERIENCE WITH INTRAPROCEDURAL ELECTRICAL IMPEDANCE TOMOGRAPHY FOR EVALUATING REGIONAL VENTILATION CHANGES DURING BRONCHOSCOPIC LUNG VOLUME REDUCTION

Chest three-dimensional-computed tomography imaging data analysis for the variation of exercise capacity after lung lobectomy.

Postoperative loss of exercise capacity and pulmonary function is a major concern among lung cancer patients. In this study, the time for a stair-climbing to 12-m height was used to investigate whether preoperative chest 3D-computed tomography (CT) could be a useful tool for predicting postoperative variations in exercise capacity and pulmonary function. Seventy-eight patients undergoing lobectomy for suspected stage I lung cancer were prospectively enroled. Preoperatively, lobe volume and low attenuation volume (LAV) were evaluated using the SYNAPSE VINCENT system. Preoperative data on stair-climbing time, spirometryand diffusing capacity of the lung for carbon monoxide (DLCO ) at baseline and 6-month postoperative data were used to evaluate variations in exercise capacity and pulmonary function. Maximal oxygen uptake (VO2 t) was evaluated based on the stair-climbing time. Significant differences in the variation of exercise capacity at 6 months postoperatively were found between the groups categorized by target lobe volume and LAV status: The large volume/LAV (+) group had a greater decline in VO2 t. Mean loss of VO2 t was -6.2%, -1.4%, -1.6%and -0.1% in the large volume/LAV (+), large volume/LAV (-), small volume/LAV (+)and small volume/LAV (-) groups, respectively. The large volume/LAV (-) group had a greater decline in forced expiratory volume in 1 s. The small volume/LAV (+)group showed a reduced decline in the DLCO . Analysis of chest 3D-CT scans is a potential tool for predicting the loss of exercise capacity and pulmonary function after lung lobectomy.