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Study objectives: To determine the effect of emphysema and lung volume reduction surgery (LVRS) on diaphragm length (Ldi) and its capacity to generate transdiaphragmatic pressure (Pdi). Design: Prospective clinical trial with a parallel group design. Setting: Laboratory investigations in normal volunteers recruited by advertisement and in emphysema outpatients being evaluated for elective LVRS. Study population: Thirteen normal subjects and 13 emphysema patients matched for age and sex. Six emphysema patients underwent LVRS. Measurements: Ldi and maximal Pdi during static inspiratory efforts (PdiMax) were measured at three different lung volumes (LVs). Pdi during maximal bilateral phrenic nerve twitch stimulation (PdiTw) was measured at functional residual capacity (FRC). All measurements were repeated at 3, 6, and 12 months postoperatively. Results: Ldi, PdiMax, and PdiTw were lower in emphysema patients than in normal subjects at their respective LVs. PdiMax and PdiTw at FRC returned within the normal range after LVRS in emphysema patients. The relationships between PdiMax and LV or Ldi were shifted respectively to higher LV and shorter Ldi in emphysema patients relative to normal subjects, both before and after LVRS. LVRS effected craniad displacement of the diaphragm but no change in rib cage dimensions. Improvements in dyspnea and quality of life after LVRS correlated with changes in LV and Ldi but not with changes in airway caliber. Conclusion: Adaptive mechanisms, consistent with sarcomere deletion, tend to restore diaphragm strength in emphysema patients at FRC, which are fully expressed after LVRS. Lung remodeling by LVRS may alter pleural surface pressure distribution, causing a sustained change in chest wall shape.

Chronic exposure to excess glucocorticoids results in cognitive and psychological impairment. A few studies have indicated that cerebral atrophy can be found in patients with Cushing's syndrome (CS), but its evolution after cure has not been studied extensively. We report the presence of apparent cerebral atrophy in CS and its reversibility after the correction of hypercortisolism. Thirty-eight patients with CS, including 21 with Cushing's disease and 17 with adrenal CS were studied. The control groups consisted of 18 patients with other non-ACTH-secreting sellar tumors and 20 normal controls. Twenty-two patients with CS were reevaluated after cure. Subjective loss of brain volume was present in 86% of patients with Cushing's disease and 100% of patients with adrenal CS. The values for third ventricle diameter, bicaudate diameter, and subjective evaluation were significantly increased in CS groups in comparison with the control group (P < or = 0.001). Imaging reevaluated at 39.7 +/- 34.1 months after achieving eucortisolism showed an improvement of the third ventricle diameter (P = 0.001), bicaudate diameter (P < 0.0005), and subjective evaluation (P = 0.05). We conclude that brain volume loss is highly prevalent in CS and is at least partially reversible following correction of hypercortisolism.

Study objectives To define anatomic landmarks that can be used to predict insertions of the diaphragm on chest radiographs and to estimate diaphragm length. Design Prospective clinical trial with a parallel group design. Setting Laboratory investigations in normal volunteers recruited by advertisement and in emphysema outpatients being evaluated for elective bilateral lung volume reduction surgery (LVRS). Patients Twenty-six normal subjects classified into young and older age groups, with a third group of 13 emphysema patients matched for age and sex with the older group. Measurements Identification and between-group comparisons were made of anatomic landmarks on anteroposterior and lateral chest radiographs obtained at total lung capacity. Predicted landmarks were generated from normal subjects. Within-subject and between-group comparisons were made of diaphragm length index (DLI) based on observed anatomic landmarks (DLIobs) and diaphragm length index based on predicted anatomic landmarks (DLIpred) at functional residual capacity. Results Anatomic landmarks were not different between the three groups or between male and female subjects, and were not different before and after LVRS in emphysema patients. No difference was found between DLIobs and DLIpred in normal subjects and emphysema patients, but both were smaller in emphysema patients than in normal subjects and increased after LVRS in emphysema patients. Conclusion This study validates the use of anatomic landmarks to estimate DLI. Using these landmarks simplifies the determination of diaphragmatic lengths and could be a useful tool for the evaluation of the functional capacity of the diaphragm, and possibly as a prognostic indicator of patients who are candidates for LVRS.

Objectives: To compare the distribution of lung volume at total lung capacity (TLC) among adult men and women known to have normal lung function or chronic obstructive disease or restrictive lung disease (RLD). Design: Five-year retrospective study. Setting: Review of available clinical pulmonary function testing (PFT) reports and chest radiographs. Patients: Sixty-four patients presenting with normal PFT and chest radiograph findings (normal subjects), 26 patients with severe COPD and increased TLC (COPD group), 29 patients with cystic fibrosis (CF) and increased TLC (CF group), and 19 patients with RLD with a clinical diagnosis of pulmonary fibrosis and a reduced TLC (RLD group). Measurements: Average posteroanterior rib cage diameter (PAave), average lateral rib cage diameter (LAave), and average vertical height of the diaphragm (HDIave) were measured using radiography. Normal prediction equations were generated based on stature, body mass index (BMI), age, and sex as independent variables and then used in between-group comparisons. Results: PAave correlated positively with BMI and age but not with height, whereas LAave correlated positively with BMI and height but not with age. HDIave correlated positively with height and age but negatively with BMI. PAave and LAave were smaller and HDIave was greater in women than men having the same stature. In the COPD group and in male CF group patients, BMI was low and only HDIave was greater than in sex-, age-, and height-matched normal subjects, but in female CF group patients, only the rib cage diameters were greater than normal. In the RLD group, PAave and HDIave were smaller than predicted and inversely related to each other, but LAave was normal. Conclusion: Variations in maximum lung volume caused by gender, growth, or by lung diseases are nonisotropic and entail substantial changes in chest wall shape. (CHEST 2001; 119:376 ‐386)

We read with interest the article ‘‘Clinical usefulness of chest radiography in detection of pulmonary metastases after curative resection for colorectal cancer’’ that was published in the July 2007 issue of World Journal of Surgery [1]. In a retrospective analysis of patients after curative resection for colorectal cancer, the authors showed that the sensitivity of abdominal computed tomography (CT) with lower thorax images was superior to chest radiography for lung metastasis detection. They concluded that elevating the upper level of the scan during abdominal CT or performing chest CT could result in higher detection of lung metastases. As Lee et al. noted, reports evaluating CT versus radiography for detecting pulmonary metastases in the context of colorectal cancer have been few and somewhat inconsistent [2, 3]. In our center, we did a prospective study in a selected subset of 96 patients undergoing preoperative evaluation for liver metastases resection, 90% of which were from colorectal cancer, with intrapatient comparison of chest radiography and whole-chest CT for the detection of lung metastases. Neoplastic confirmation of lung lesions was done either by lung biopsy or evidence of growth on follow-up. Lung metastases were present in 13 patients (13.5%). Chest CT was more sensitive than radiography and alone prevented unnecessary liver surgery in three patients (3.1%) in whom chest radiography was normal. Four other chest CT-positive/chest radiography-negative patients were not operated on based on the nonresectability of liver lesions demonstrated by abdominal CT. In six patients, lung metastases were demonstrated by both chest CT and radiography. Incidental CT visualization of indeterminate small lung nodules (too small for characterization with biopsy or positron emission tomography) remains a potential drawback of routine chest CT for colorectal cancer in a small number of patients. Those patients require follow-up chest CT [4]. Since our prospective study, we have included chest CT in the preoperative evaluation of our patients for colorectal liver metastases resection. This is especially valuable with the wider indications of surgical resection of liver metastases allowed by the use of improved combination chemotherapy regimens [5].

Objectifs L’etude a pour but de verifier la fiabilite d’un logiciel de volumetrie automatisee sur des nodules synthetiques dans un fantome thoracique et d’etudier l’influence de diverses variables sur la reproductibilite des resultats. Materiels et methodes Le fantome utilise (« Lungman » avance) contient un total de 80 nodules, solides et en verre depoli, de forme ronde et irreguliere, a differentes localisations (intraparenchymateuse, sous-pleurale, juxtavasculaire, paramediastinale), de diametre et de densite variant de 3 a 20 mm, et − 800 a +100 HU respectivement. Le fantome a ete image a l’aide d’un CT 16-barettes, epaisseur de coupe de 0,75 mm, reconstructions de 2 mm et 5 mm, dose standard (180 mAs) et faible (40 mAs), 120 Kv. La segmentation et les mesures de tous les nodules ont ete effectuees avec le logiciel de volumetrie Lungcare (Siemens) par deux observateurs aveugles, puis comparees aux valeurs de volumes reels. Resultats La fiabilite du logiciel est comparable a celle rapportee par la litterature pour les nodules solides, peu importe la forme, la localisation et la dose d’exposition (taux d’erreur maximal de 15 % a une taille Conclusion L’interet du projet repose sur le nombre de nodules et de variables simulant les conditions rencontrees in vivo, incluant une etude comparative dose standard et faible dose.