Lung Volume Research Articles

Predictors of the efficacy of CO2 laser therapy for female stress urinary incontinence

Background: Predictors of the efficacy of a single-session of CO2 laser therapy for female stress urinary incontinence are important for pretreatment consultation. Thus, the objective of this study was to evaluate these predictors. Methods: All consecutive women who underwent vaginal CO2 laser therapy for stress urinary incontinence were prospectively enrolled. Results: The median duration of subjective improvement (defined as ≥1 on the global response assessment) was 18.3 months (95% confidence interval (CI): 12.1 to 18.3 months, n = 75). Multivariable analysis revealed that low voided volume (dL, hazard ratio [HR] = 0.707; area under the curve [AUC] = 0.66, cutoff value of voided volume ≤4.0 dL), high postvoid residual volume (dL, HR = 2.714; AUC = 0.60, cutoff value of postvoid residual volume ≥1.0 dL), and low functional profile length (HR = 0.956; AUC = 0.58, cutoff value of functional profile length ≤2.8 cm) were predictors of subjective failure. A logit(p) = 1.0 - 0.5 x (voided volume) + 0.9 x (postvoid residual volume) can be used to predict failure (HR = 1.775; AUC = 0.71, cutoff value of logit(p) ≥0.0). Pad weights decreased at 3 and 6-month follow-up visits. At 6 months, 8 women (21%) were cured (<1 g pad weight), and 16 women (42%) showed improvement (>50% decrease in pad weight). Overactive bladder symptoms improved at 3 and 6 months. However, there was no change in female sexual function from baseline. Conclusion: A low voided volume and high postvoid residual volume can be used to predict subjective failure after one session of transvaginal CO2 laser therapy. However, the subjective therapeutic effect may diminish within a median duration of 18 months.

Deep Learning-Based Postoperative Glioblastoma Segmentation and Extent of Resection Evaluation: Development, External Validation, and Model Comparison

Abstract Background The pursuit of automated methods to assess the extent of resection (EOR) in glioblastomas is challenging, requiring precise measurement of residual tumor volume. Many algorithms focus on preoperative scans, making them unsuitable for postoperative studies. Our objective was to develop a deep learning-based model for postoperative segmentation using magnetic resonance imaging (MRI). We also compared our model's performance with other available algorithms. Methods To develop the segmentation model, a training cohort from three research institutions and three public databases was used. Multiparametric MRI scans with ground truth labels for contrast enhancing tumor, edema, and surgical cavity, served as training data. The models were trained using MONAI and nnU-Net frameworks. Comparisons were made with currently available segmentation models using an external cohort from a research institution and a public database. Additionally, the model's ability to classify EOR was evaluated using the RANO-Resect classification system. To further validate our best-trained model, an additional independent cohort was used. Results The study included 586 scans: 395 for model training, 52 for model comparison, and 139 scans for independent validation. The nnU-Net framework produced the best model with median Dice scores of 0.81 for contrast enhancing tumor, 0.77 for edema, and 0.81 for surgical cavity. Our best-trained model classified patients into maximal and submaximal resection categories with 96% accuracy in the model comparison dataset and 84% in the independent validation cohort. Conclusion Our nnU-Net-based model outperformed other algorithms in both segmentation and EOR classification tasks, providing a freely accessible tool with promising clinical applicability.

Predicting life-threatening hemoptysis in traumatic pulmonary parenchymal injury using computed tomography semi-automated lung volume quantification.

Chest computed tomography (CT) can diagnose and assess the severity of pulmonary contusions. However, in cases of severe lung contusion, the total lung volume ratio may not accurately predict severity. This study investigated the association between life-threatening hemoptysis and chest CT imaging data on arrival at the emergency department in patients with pulmonary contusions or lacerations due to blunt chest injury. The records of 277 patients with lung contusions or lacerations treated at a trauma center between 2018 and 2022 were retrospectively reviewed. The ratio of the local lung contusion volume to lobe volume in each lobe was calculated from chest CT images. The maximal ratio in the Hounsfield unit (HU) range was defined as the highest ratio value within the HU range among five lobes. The median patient age was 41 years, and 68.6% were male. Life-threatening hemoptysis occurred in 39 patients. The area under the receiver operating characteristic curve for the maximal ratio at -500 HU to 100 HU was 96.52%. The cutoff value was 45.49%. Multivariate analysis showed a high maximal chest CT ratio ≥ 45.49% at -500 HU to 100 HU (adjusted odds ratio [aOR]: 104.66, 95% confidence interval [CI]: 21.81-502.16, p < 0.001), hemopneumothorax (aOR: 5.18, 95% CI: 1.25-21.47, p = 0.023), and chest abbreviated injury scale (AIS, aOR: 5.58, 95% CI: 1.68-18.57, p = 0.005) were associated with life-threatening hemoptysis. Maximal chest CT ratios ≥ 45.49% at -500 HU to 100 HU, hemopneumothorax, and high chest AIS scores are associated with life-threatening hemoptysis in patients with blunt chest trauma. The present study provides an objective index derived from chest CT images to predict the occurrence of life-threatening hemoptysis. This information helps screen high-risk patients in need of more intensive monitoring for early intervention to improve outcomes. Emergency department CT helps predict life-threatening hemoptysis in patients with lung contusions. Maximal CT ratios ≥ 45.49% (-500 HU to 100 HU, either lung lobe) are associated with life-threatening hemoptysis. High chest abbreviated injury scale scores and hemopneumothorax also predict life-threatening hemoptysis.

Holmium laser enucleation of the prostate: Modified urethral mucosa pre-dissected technique versus traditional three-lobe technique-A retrospective study.

The aim of this study is to investigate the effect of modified holmium laser enucleation of the prostrate (HoLEP) on the function of urine control. An analysis was conducted on a cohort of 305 elderly patients in a retrospective study spanning from February 2019 to February 2023. The cohort consisted of 150 patients who underwent modified HoLEP and 155 patients who underwent traditional HoLEP. Factors such as age, length of membranous urethra, prostate volume, BMI, IPSS, Qmax, enucleated weight, enucleation time, post-operative bladder irrigation time, catheterization and hospitalization were compared between both the groups. Multivariable logistic regression was used to identify independent predictors of urinary incontinence, and receiver operating characteristic (ROC) curve was used to determine the sensitivity and specificity of urethral membrane length in the diagnosis of urinary incontinence. Postoperative Qmax,IPSS, V2 were compared between 2 groups in the 6th month. Groups were compared in terms of age, volume, BMI, IPSS, Qmax and membranous urethral length (MUL). The time of enucleation, bladder irrigation, post-operative catheterization and hospitalization was lower in the modified HoLEP group (p < 0.05). The incidence of urinary incontinence (UI) in the modified group had a statistically significant decrease at 3months (3.3% vs 9.7%, p = 0.025) and 6months (0.6% vs 5.2%, p = 0.048). The median MUL had a significant difference in the 1st month (15.07 vs 12.5mm, p < 0.001). In multivariate regression analysis, older age (OR per SD = 1.102, 95%CI: 1.077-1.136), shortened MUL (OR per SD = 0.776, 95%CI: 0.629-0.957) and increased enucleated prostate weight (OR per SD = 1.29,95%CI: 1.005-1.084) were significantly associated with UI. The ROC curve revealed the threshold value of MUL was 13.5mm, the sensitivity was 76.7%, and the specificity was 98.1%. The modified HoLEP technique is safe and effective on the function of urine control, and is superior to less residual prostate volume and higher maximum urine flow rate after surgery.

Lung Point in a Case of Bronchoscopy Lung Volume Reduction: Consider Its Mimics Before Inserting the Tube

Point of Care Ultrasound (POCUS) is used to evaluate many clinical scenarios. Chest POCUS has been integrated as a part of a clinical protocol to assess patients with lung pathology [1]. The ability to detect pneumothorax using chest POCUS has been shown to be superior to chest radiography, with specificity reported to be as high as 100% when a lung point sign is identified. In addition to improved diagnostic accuracy, chest POCUS has the added benefits of ease of access and absence of ionizing radiation. Here we describe a case where a patient with a high pre-test probability for pneumothorax had a detected lung point sign, but pneumothorax was ruled out via Computed Tomography (CT). This case highlights the importance of considering the mimics of the lung point sign. This case also shows a unique and interesting finding related to pleural movement restriction post-Bronchoscopic lung volume reduction (BLVR).

Endobronchial valve treatment improves diaphragm function in severe emphysema patients

Rationale and aimDiaphragm dysfunction is common in severe emphysema patients, primarily due to hyperinflation, placing the diaphragm at a mechanical disadvantage. Endobronchial valve (EBV) treatment is a bronchoscopic procedure to reduce hyperinflation, and thus potentially restore diaphragm function in this patient population. Our aim was to investigate the effect of EBV treatment on diaphragm function.Patients and methodsA prospective cohort study was performed in which diaphragm function was measured at baseline and 6 weeks after EBV treatment by ultrasonic assessment to measure diaphragm motion and diaphragm thickening fraction (dTF), surface electromyography (sEMG) to quantify diaphragm activity, and maximal inspiratory pressure (MIP) to assess diaphragm strength.ResultsTwenty-five patients were included, with a mean age of 64±7 years. Residual volume (−0.85±0.49 Liter, p&lt;0.001) decreased significantly post EBV treatment, with a significant increase in MIP (+0.6 kPa, range −1.2–2.8, p=0.001). Diaphragm motion on the treated side during tidal breathing significantly decreased (−3.3 mm, range −24.7–14.6, p=0.023). There were no significant changes in dTF on the treated side. Diaphragm activity (sEMG) for tidal breathing (−1.7 µV, p=0.004, range −8.8–5.8), maximal inspiration (−4.1 µV, p=0.004, range −42.3–16.0), and sniff manoeuvre (−6.1 µV, p=0.027, range −42.2–24.2) all significantly decreased.ConclusionOur results show that diaphragm function significantly improves after EBV treatment in severe emphysema patients. This emphasizes the physiological interaction between hyperinflation and diaphragm function, suggesting that reducing hyperinflation can at least partially reverse diaphragm dysfunction.

4DCT image artifact detection using deep learning.

Four-dimensional computed tomography (4DCT) is an es sential tool in radiation therapy. However, the 4D acquisition process may cause motion artifacts which can obscure anatomy and distort functional measurements from CTscans. We describe a deep learning algorithm to identify the location of artifacts within 4DCT images. Our method is flexible enough to handle different types of artifacts, including duplication, misalignment, truncation, andinterpolation. We trained and validated a U-net convolutional neural network artifact detection model on more than 23000 coronal slices extracted from 98 4DCT scans. The receiver operating characteristic (ROC) curve and precision-recall curve were used to evaluate the model's performance at identifying artifacts compared to a manually identified ground truth. The model was adjusted so that the sensitivity in identifying artifacts was equivalent to that of a human observer, as measured by computing the average ratio of artifact volume to lung volume in a givenscan. The model achieved a sensitivity, specificity, and precision of 0.78, 0.99, and 0.58, respectively. The ROC area-under-the-curve (AUC) was 0.99 and the precision-recall AUC was 0.73. Our model sensitivity is 8% higher than previously reported state-of-the-art artifact detectionmethods. The model developed in this study is versatile, designed to handle duplication, misalignment, truncation, and interpolation artifacts within a single image, unlike earlier models that were designed for a single artifact type.

Assessing the Severity of Connective Tissue-Related Interstitial Lung Disease Using Computed Tomography Quantitative Analysis Parameters

Objectives The aims of the study are to predict lung function impairment in patients with connective tissue disease (CTD)-associated interstitial lung disease (ILD) through computed tomography (CT) quantitative analysis parameters based on CT deep learning model and density threshold method and to assess the severity of the disease in patients with CTD-ILD. Methods We retrospectively collected chest high-resolution CT images and pulmonary function test results from 105 patients with CTD-ILD between January 2021 and December 2023 (patients staged according to the gender-age-physiology [GAP] system), including 46 males and 59 females, with a median age of 64 years. Additionally, we selected 80 healthy controls (HCs) with matched sex and age, who showed no abnormalities in their chest high-resolution CT. Based on our previously developed RDNet analysis model, the proportion of the lung occupied by reticulation, honeycombing, and total interstitial abnormalities in CTD-ILD patients (ILD% = total interstitial abnormal volume/total lung volume) were calculated. Using the Pulmo-3D software with a threshold segmentation method of −260 to −600, the overall interstitial abnormal proportion (AA%) and mean lung density were obtained. The correlations between CT quantitative analysis parameters and pulmonary function indices were evaluated using Spearman or Pearson correlation coefficients. Stepwise multiple linear regression analysis was used to identify the best CT quantitative predictors for different pulmonary function parameters. Independent risk factors for GAP staging were determined using multifactorial logistic regression. The area under the ROC curve (AUC) differentiated between the CTD-ILD groups and HCs, as well as among GAP stages. The Kruskal-Wallis test was used to compare the differences in pulmonary function indices and CT quantitative analysis parameters among CTD-ILD groups. Results Among 105 CTD-ILD patients (58 in GAP I, 36 in GAP II, and 11 in GAP III), results indicated that AA% distinguished between CTD-ILD patients and HCs with the highest AUC value of 0.974 (95% confidence interval: 0.955–0.993). With a threshold set at 9.7%, a sensitivity of 98.7% and a specificity of 89.5% were observed. Both honeycombing and ILD% showed statistically significant correlations with pulmonary function parameters, with honeycombing displaying the highest correlation coefficient with Composite Physiologic Index (CPI, r = 0.612). Multiple linear regression results indicated honeycombing was the best predictor for both the Dlco% and the CPI. Furthermore, multivariable logistic regression analysis identified honeycombing as an independent risk factor for GAP staging. Honeycombing differentiated between GAP I and GAP II + III with the highest AUC value of 0.729 (95% confidence interval: 0.634–0.811). With a threshold set at 8.0%, a sensitivity of 79.3% and a specificity of 57.4% were observed. Significant differences in honeycombing and ILD% were also noted among the disease groups (P &lt; 0.05). Conclusions An AA% of 9.7% was the optimal threshold for differentiating CTD-ILD patients from HCs. Honeycombing can preliminarily predict lung function impairment and was an independent risk factor for GAP staging, offering significant clinical guidance for assessing the severity of the patient's disease.

Outcomes of adjuvant radiation treatment following subtotal resection of world health organization grade II meningiomas.

Existing literature on adjuvant radiation after subtotal resection (STR) of WHO II meningiomas is limited by heterogenous patient cohorts, combining adjuvant and salvage radiation, gross total resection (GTR) and STR, primary radiation treatment vs. re-treatment, or grade II and III meningiomas, all of which have different expected outcomes. Tumor control estimates in a large homogenous patient cohort are needed to accurately counsel patients. A retrospective review of patients that had immediate post-operative imaging-confirmed residual WHO grade II meningioma followed by either adjuvant intensity-modulated radiation therapy (IMRT) or stereotactic radiosurgery (SRS) between 1996 and 2020 was conducted. Kaplan-Meier survival analysis and log-rank test was used to assess progression-free survival (PFS). Thirty-nine patients met inclusion criteria (IMRT = 32; SRS = 7). Overall, the 3-, 5-, and 10-year PFS was 81.1%, 61.2%, and 44.6%, respectively. Median follow-up time was 37 months. When comparing IMRT and SRS cohorts, baseline characteristics did not differ significantly between groups, but significantly larger residual tumor volumes were treated with IMRT (22.2 cm3 vs. 6.3 cm3, p = 0.004). PFS was not significantly different between IMRT and SRS at 3 years (81.1% vs. 80.0%) or 5 years (65.5% vs. 40%) (p = 0.19). There was no significant difference in radiation necrosis between groups (IMRT = 3/32 patients vs. SRS = 0/7 patients, p = 0.32). Our homogenous patient cohort displayed acceptable control rates at 3 years using SRS or IMRT as adjuvant therapy. No significant difference in PFS or radiation necrosis was noted between patients treated with adjuvant IMRT versus SRS.

Modeling ventilation of patients with interstitial lung disease at rest and exercise: a bench study.

The ventilatory physiopathology of patients with interstitial lung disease (ILD) remains poorly understood. We aimed to personalize a mechanical simulator to model healthy and ILD profiles ventilation, and to evaluate the effect of spontaneous breathing on respiratory mechanics at rest and during exercise. In a 2-compartment lung simulator (ASL 5000®), we modeled 1 healthy and 3 ILD profiles, at rest and during exercise, based on physiological data from literature and patients. Measurements were: tidal volume, end-expiratory lung volume, driving pressure, transpulmonary driving pressure, dynamic alveolar strain, mechanical power, and time lag of inspiratory flow between compartments 1 and 2. Healthy and ILD models were validated: maximum differences between real and simulated tidal volume were 5% (96ml) and 6% (54ml) at rest and during exercise respectively, considered clinically negligible. When we simulated lung inhomogeneity (compliance in compartment 1 > compartment 2), tidal volume, end-expiratory lung volume, driving pressure and mechanical power increased in compartment 1 and decreased in compartment 2. Driving transpulmonary pressure and dynamic alveolar strain increased in compartment 2 and decreased in compartment 1. Time lag of inspiratory flow between compartments 1 and 2 was positively correlated with a difference of compliance between compartments (r = 0.98, CI95% (0.9106; 0.9962), p < 0.0001). In this bench study, we personalized a mechanical simulator thatmodels the lung inhomogeneity and spontaneous breathing of healthy subjects and ILD patients at rest and during exercise. Our results suggest that lung inhomogeneity could increase lung vulnerability to volo-atelec-trauma mechanisms in ILD. Further physiological studies are needed to evaluate the impact of this vulnerability on acute or chronic ILD worsening.

Impact of deep inspiration breath hold, surface-guided radiotherapy, and daily CBCT on the organs at risk in breast cancer radiotherapy.

The goal of the study was to assess the impact of deep inspiration breath hold technique (DIBH), surface-guided radiotherapy (SGRT), and daily kilovoltage cone-beam computed tomography (kV-CBCT) on the dose to organs at risk (OAR) in left-sided breast cancer radiotherapy. Twenty-six consecutive left-sided breast cancer patients treated using Volumetric Intensity Modulated Arc Therapy (VMAT), DIBH, SGRT, and a hypofractionated regimen were retrospectively evaluated in this study. Dose parameters were extracted from dose-volume histograms (DVH). The Wilcoxon Matched Pairs test was used to test dose parameters obtained in free breathing (FB) and DIBH for statistical significance. Multivariable analysis of variance (ANOVA) and receiver operating characteristics (ROC) analysis were used to identify parameters and cut-off points associated with the reduction of the mean heart dose (MHD) by DIBH. Based on published models, the risk of cardiac and lung toxicity (pneumonitis) using SGRT or daily kV-CBCT was estimated and compared. DIBH substantially reduced the MHD (median, 43.6%; range, 4.2% to 75.1%; P < 0.00001). The risk of cardiac toxicity using SGRT increased by 1%, compared to 3.6% to 20.5% using daily kV-CBCT. No significant difference in the risk of radiation-induced pneumonitis using SGRT versus daily kV-CBCT was detected. The ANOVA revealed the relative increase of the left lung volume by DIBH as the only significant impact factor for the MHD. The ROC analysis of this parameter showed an area under the curve (AUC) of 0.89 (95%CI, 0.71 to 0.98; P < 0.0001). DIBH can substantially reduce the MHD in left-sided breast cancer patients treated with modern radiotherapy techniques and hypofractionation. Patient setup using SGRT compared to daily kV-CBCT may be the preferred option for many patients. In our patient cohort, the relative reduction of the left lung volume by DIBH can be used as a predictor to select patients who benefit from DIBH.

Peritoneal Catheters Malposition/Dysfunction and Their Approach with Catheterography and Radiologic Manipulation in Peritoneal Dialysis: A Minireview and Case Series

Peritoneal catheter dysfunction is one of the most frequent complications of peritoneal dialysis. The malposition of a peritoneal catheter may cause one- or two-way obstruction with fluid outflow or inflow problems, large residual volumes, and, therefore, reduced ultrafiltration and sometimes abdominal pain. Standard procedures may often fail to solve the dysfunction. Catheterography is an interventional radiologic procedure based on the infusion under aseptic conditions of iodated contrast into the peritoneal catheter, followed by the introduction of a guidewire into the catheter for guidewire manipulation. The available literature about catheterography is quite scarce and mainly based on case reports, case series, and small retrospective studies. In this minireview, we describe the guidewire manipulation techniques explored so far and their pros and cons. In addition, four interesting cases of catheterography performed in our center are also reported. In conclusion, in this minireview, the pros and cons of catheterography have been outpointed. Radiologic manipulation of peritoneal catheters may represent an effective and safe solution for malfunctioning peritoneal catheters and may also be exploited as “bridge therapy” to laparotomy in patients temporarily unsuitable for surgery. The advantages of this procedure are that it does not require long-term hospitalization and allows immediate resume of peritoneal dialysis.

Abstract 4135534: Total and Regional Lung Volumes And Pulmonary Blood Flow In Repaired Tetralogy Of Fallot - Smaller Lungs And A Maldistribution of Flow

Introduction: Many pts with repaired tetralogy of Fallot (rTOF) are left with residual pulmonary regurgitation (PR) and poor exercise performance. Small studies in young children suggest that the total lung volume of rTOF pts are smaller than normal and may contribute to these sequelae. As exercise and cardiac performance are intimately related to lung function, it’s surprising that few rTOF studies have investigated cardiopulmonary interactions. Aims: To determine if regional and total lung volumes in rTOF pts are the same size as normals and if the larger amount of forward blood flow courses to the bigger lung. We hypothesized that this may not be the case. Methods: rTOF patients undergoing clinically indicated cardiac magnetic resonance (CMR) were evaluated for lung volumes using dark blood imaging (figure) and blood flow to the branch pulmonary arteries (bPA) using velocity mapping. Significance &lt; P=0.05. Results: Eleven rTOF patients and 25 normal controls were studied. Total control lung volume was significantly larger than those of rTOF. Regional rTOF right and left lung volumes were smaller than their respective control lung volumes, barely missed statistical significance (table). In 6 rTOF pts with CMR prior to and after pulmonary valve replacement (PVR), lung volumes did not differ between the 2 timepoints (1034 vs 998 cc/m 2 respectively). Only 3/11 (27%) rTOF pts had the higher bPA flow coursing to the higher regional lung. The ratio of right bPA forward flow/right lung volume to left bPA forward flow/left lung volume ranged from 0.72-1.51 (ideal balanced flow to each lung would be 1), implying a maldistribution of flow. Conclusion: rTOF patients have smaller total lung volumes than controls with no change after PVR in our study. In addition, only a small proportion of rTOF patients have the larger amount of flow coursing to the larger lung. The ratio of individual bPA flow to individual lung volume implies a maldistribution of pulmonary flow relative to the respective lung volume. Our findings may have implications for timing of PVR, partially explaining PR and poor exercise performance. Flow limiters placed by cath or surgery may be able to redistribute the appropriate flow to regional lung fields.

Evaluation of Volumetric Magnetic Resonance Imaging in Determining the Indication for Total Neoadjuvant Therapy in Rectal Cancer.

This study aims to evaluate the relationship between volumetric measurements of residual tumor via magnetic resonance imaging (MRI) and pathologic complete response (pCR) in rectal cancer patients undergoing neoadjuvant chemoradiotherapy (nCRT). Patients with locally advanced rectal cancer who had pelvic MRI for clinical staging and completed nCRT followed by radical resection were included. Two experienced radiologists measured tumor volume on MRI obtained before and after nCRT. We compared the pre- and post-CRT tumor volume and measured tumor volume reduction rates. The median value of tumor volume reduction rate in all patients was 64.7% (min-max - 81.1-98.1%). When the relationship between tumor volume and tumor regression grade (TRG) after nCRT was assessed, it was found that 18 of 21 (86%) patients with a good response (TRG 1) had a post-CRT tumor volume of ≤ 8 cm3 (p = 0.001). While 9 of 10 patients with pCR after nCRT had a tumor volume of ≤ 8 cm3, one patient had pCR despite having a tumor volume greater than 8 cm3 (p = 0.015). The correlation between post-nCRT residual tumor volume and pCR underscores the potential of volumetric MRI as a predictive tool in tailoring rectal cancer treatment. For patients with residual tumor volumes greater than 8 cm3, extending neoadjuvant chemotherapy as part of TNT may enhance the likelihood of achieving pCR. This approach advocates for a more personalized treatment strategy, potentially optimizing outcomes for rectal cancer patients.

The prognostic importance of glioblastoma size and shape.

Extent of resection, MGMT promoter methylation status, age, functional level, and residual tumor volume are established prognostic factors for overall survival in glioblastoma patients. Preoperative tumor volume has also been investigated, but the results have been inconclusive. We hypothesized that the surface area and the shape were more representative of the tumor's infiltrative capacities, and thus, the purpose of this study was to assess the prognostic value of tumor size and shape in patients with glioblastoma. In total, 271 patients with primary, unifocal glioblastoma were included from two centers in Norway and Sweden, respectively. All tumors were automatically segmented on preoperative MRI scans and manually validated. Tumor volume was used as a measurement of size, whereas sphericity index and area-to-volume ratio defined the shape complexity of the tumor. Contact surface area of the tumor was considered a measurement of both size and shape. Multivariable Cox proportional hazards models were used to assess the prognostic value of the respective tumor measurements, with previously established prognostic factors as covariates. There were no associations between preoperative tumor volume and overall survival. Contact surface area (HR = 1.013, p = 0.002) and sphericity index (HR = 2.223, p = 0.001) were both significant independent prognostic factors for survival in the multivariable Cox models. Contact surface area was also associated with MGMT promoter methylation (p = 0.039) and extent of resection (p = 0.017). Tumor shape complexity appears to be an independent prognostic factor in glioblastoma patients and may also be associated with MGMT promoter methylation status and extent of surgical resection.

Chronic airway diseases: a new frontier in interventional pulmonology

As medical science has advanced, the incidence of central airway lesions, traditionally the primary focus of interventional pulmonology, has decreased significantly. However, the large population suffering from chronic airway diseases, coupled with unmet treatment needs and a high demand for new technologies and methods, has greatly driven the innovation and application of interventional respiratory techniques. The development and clinical application of techniques such as lung volume reduction, targeted lung denervation, pulsed electric field technology, bronchial thermoplasty, and regenerative medicine for chronic airway diseases are providing new treatment options. Chronic airway diseases are becoming a new frontier in interventional pulmonology.

Clinical application and challenges of thermal vapor lung volume reduction

There are major clinical challenges in the management of chronic obstructive pulmonary disease (COPD). Recent studies suggest that thermal vapor lung volume reduction may be an important interventional method in the treatment of emphysema phenotype of COPD. In this article, we reviewed and summarized the research and development, the current situation of clinical application, and the clinical challenges of thermal vapor lung volume reduction, to provide further clinical evidence for the standardized application of thermal vapor lung volume reduction.

Application and innovation of bronchoscopic lung volume reduction with endobronchial valve

Bronchoscopic lung volume reduction with endobronchial valve (BLVR-EBV) involves the placement of an endobronchial valve (EBV) in the emphysema area of patients with chronic obstructive pulmonary disease (COPD) via bronchoscopy, resulting in the collapse of the target lung lobe. This procedure has been shown to improve pulmonary function, quality of life, and activity endurance in COPD patients. Strict selection criteria and thorough preoperative evaluation are essential to ensure the success of BLVR-EBV. Due to its excellent postoperative performance, BLVR-EBV has been widely used in the treatment of patients with end-stage COPD, including those with conditions such as pulmonary tuberculosis cavities or those requiring surgical treatment. This paper provided a brief overview of the application and innovation of BLVR-EBV in patient assessment, perioperative management, and postoperative outcomes.

Cigarette Smoking Impairs Cardiorespiratory and Metabolic Response at Peak Incremental Exercise and during Recovery in Young, Physically Active Adults

ABSTRACT Purpose: Cigarette smoking (CS) induces systemic changes that impair cardiorespiratory and muscular function both at rest and during exercise. Although these abnormalities are reported in sedentary, middle-aged smokers (SM) with pulmonary disease, few and controversial studies focused on young, physically active SM at the early stage of smoking history. This study aimed at assessing the impact CS on cardiorespiratory and metabolic response during an incremental test and the subsequent recovery in young, physically active SM without known lung or cardiovascular disease. Methods: After pulmonary function evaluation, 12 SM (age: 22±2 yr; body mass: 75±8 kg; stature: 1.78±0.06 m; 12±4 cigarette/day for 6±2 years; mean±SD) and 12 non-smokers (CTRL; age: 23±1 yr; body mass: 76±8 kg; stature: 1.79±0.08 m) matched for age and exercise habits, underwent an exhaustive incremental step test (25 W/2 min) on a cycle ergometer. Pulmonary O2 uptake (V’O2), expiratory ventilation (V’E), heart rate (f H) responses and lactate concentration were assessed during the test and subsequent recovery. Results: Despite similar static lung volumes, SM reported lower peak expiratory flow (-23%; P = 0.003) and maximal voluntary ventilation (-10%; P = 0.003). At submaximal exercise, no differences in the cardiorespiratory and metabolic were noted between the two groups. However, SM exhibited ventilatory (P &lt; 0.01) and lactate thresholds at lower work rates (P = 0.01). At peak exercise, SM exhibited lower V’O2 (-8%; P = 0.02), mechanical power (-11%; P = 0.02) and V’E (-9%; P = 0.01). During recovery, SM showed longer time constants (τ) in V’O2 (+52%; P = 0.002), V’E (+19%; P = 0.027) and f H (+21%; P = 0.022) and smaller f H at 30 s of recovery (HRR30; -31%; P = 0.032). Conclusions: These results are compatible with an early CS-related impairment of the cardiorespiratory and metabolic function even in young individuals with relatively short smoking history.

NIMG-24. PRECISION GLIOBLASTOMA MANAGEMENT USING MET AND FMISO PET SCANS

Abstract OBJECTIVE Positron Emission Tomography (PET) may be useful in diagnosing glioblastoma, determining resection areas, and evaluating therapeutic efficacy. This study evaluated the usefulness of PET scans using 11C-Methionine (MET) to assess amino acid metabolism and 18F-Fluoromisonidazole (FMISO) to assess hypoxic regions in glioblastoma treatment. METHODS Thirty glioblastoma patients who underwent MET and FMISO PET studies from July 2013 to March 2024 were included. Patients underwent the Stupp regimen post-tumor resection and were treated with temozolomide (TMZ) and bevacizumab (Bev) upon recurrence. PET scans were performed before and after two courses of Bev treatment. Changes in tumor to normal ratio (TNR) for MET, tumor to blood ratio (TBR) for FMISO, and metabolic tumor volume (MTV) for both MET and FMISO were evaluated. Progression-free survival (PFS) and overall survival (OS) were compared based on the rate of change in MTV for MET and FMISO. RESULTS The residual volumes (contrast-enhanced MRI, MET, and FMISO) with a MET removal rate of &amp;gt;90% were 0.08 ml, 0.1 ml, and 0.08 ml, respectively. For FMISO removal rates of &amp;gt;90%, residual volumes were 0.36 ml, 1.54 ml, and 0.05 ml, respectively. Groups with a decreased rate of change in MET MTV had significantly better outcomes: PFS (months) 10.7 vs. 2.8 (p=0.19) and OS (months) 18.6 vs. 4.9 (p=0.09). In the FMISO groups, decreased TBR change rates correlated with better outcomes: PFS (months) 16.6 vs. 2.5 (p&amp;lt;0.01) and OS (months) 22.8 vs. 4.9 (p&amp;lt;0.01). MTV change rates also showed significant differences in outcomes: PFS (months) 10.5 vs. 3.7 (p=0.76) and OS (months) 14.9 vs. 7.0 (p=0.87). CONCLUSION Higher MET removal rates correlate with fewer contrast-enhanced MRI and FMISO accumulation areas, suggesting MET as a reliable tumor removal indicator. Both MET and FMISO PET scans are valuable in determining glioblastoma treatment response.