The Prevalence of Blebs or Bullae Among Young Healthy Adults

Association of Underlying Comorbidities and Sites of tuberculosis: an analysis using surveillance data

Background

Tuberculosis (TB) is a highly heterogeneous disease that can affect any organ. Extrapulmonary TB (EPTB) is more difficult to diagnose due to various clinical presentations. Depending on the characteristics of the patient, the involved site of TB may vary. However, data on clinical characteristics of EPTB are inconsistent and insufficient. This study aimed to identify the characteristics of patients with pulmonary TB (PTB) and EPTB and describe characteristic differences for each involved site.

Methods

We systemically collected data of TB patients included in the national surveillance system in South Korea from July 2018 to June 2019 and compared the characteristics of patients with EPTB with that of PTB.

Results

A total of 7674 patients with a mean age of 60.9 years were included. Among them, 6038 (78.7%) patients were diagnosed with PTB and 1636 (21.3%) with EPTB. In PTB group, the mean age (61.7 ± 18.7 vs. 57.8 ± 19.9) and proportion of male sex (63.3% vs. 50.1%) were higher, but the body mass index was lower (21.2 ± 3.4 vs. 22.7 ± 3.5) than that of the EPTB group. Prevalence of diabetes (20.5% vs. 16.9%) and chronic lung disease (5.1% vs. 2.9%) were higher in PTB group, meanwhile, those of chronic kidney disease (CKD) (2.7% vs. 5.4%) and long-term steroid use (0.4% vs. 1.0%) were higher in EPTB group. Abdominal TB was more prevalent in patients with chronic liver disease (odds ratio [OR]: 2.69, 95% CI: 1.52–4.74), and urogenital TB was more prevalent in patients with CKD (OR: 2.75, 95% CI: 1.08–6.99).

Conclusions

We found that underlying comorbidities were closely associated with the location of TB development, and therefore, the possibility of EPTB should be carefully evaluated while monitoring for underlying disease in TB-endemic areas.

Chest CT scan for the screening of air anomalies at risk of pulmonary barotrauma for the initial medical assessment of fitness to dive in a military population

Introduction: The presence of intra-pulmonary air lesions such as cysts, blebs and emphysema bullae, predisposes to pulmonary barotrauma during pressure variations, especially during underwater diving activities. These rare accidents can have dramatic consequences. Chest radiography has long been the baseline examination for the detection of respiratory pathologies in occupational medicine. It has been replaced since 2018 by the thoracic CT scan for military diving fitness in France. The objective of this work was to evaluate the prevalence of the pulmonary abnormalities of the thoracic CT scan, and to relate them to the characteristics of this population and the results of the spirometry.

Methods: 330 records of military diving candidates who underwent an initial assessment between October 2018 and March 2021 were analyzed, in a single-center retrospective analysis. The following data were collected: sex, age, BMI, history of respiratory pathologies and smoking, treatments, allergies, diving practice, results of spirometry, reports of thoracic CT scans, as well as fitness decision.

Results: The study included 307 candidates, mostly male, with a median age of 25 years. 19% of the subjects had abnormal spirometry. We identified 25% of divers with CT scan abnormalities. 76% of the abnormal scans were benign nodules, 26% of which measured 6 mm or more. Abnormalities with an aerial component accounted for 13% of the abnormal scans with six emphysema bullae, three bronchial dilatations and one cystic lesion. No association was found between the presence of nodules and the general characteristics of the population, whereas in six subjects emphysema bullae were found statistically associated with active smoking or abnormal spirometry results.

Conclusion: The systematic performance of thoracic CT scan in a young population free of pulmonary pathology revealed a majority of benign nodules. Abnormalities with an aerial component are much less frequent, but their presence generally leads to a decision of unfitness. These results argue in favor of a systematic screening of aeric pleuro-pulmonary lesions during the initial assessment for professional divers.

Preoperative bullae and subsequent pneumothorax in 6605 patients who underwent robotic prostatectomy

PURPOSE

Robotic prostatectomy is the most common surgical approach for treating prostate cancer. Patients undergoing robotic prostatectomy may have bullae, which may rupture leading to pneumothorax. We evaluated the incidence of pneumothorax due to preoperative bullae rupture in robotic prostatectomy.

METHODS

A large retrospective study of patients who underwent robotic prostatectomy between 2009 and 2021 was conducted. Bullae were detected using chest computed tomography. Pneumothorax was detected using a chest X-ray. The primary outcome was the incidence of pneumothorax due to bullae rupture. Secondary outcomes were the prevalence of preoperative bullae and the evaluation of postoperative outcomes, including length of hospital stay, intensive care unit admission rate, and prolonged intensive care unit stay (> 2 days).

RESULTS

A total of 6605 patients were included. The prevalence of preoperative bullae was 3.0% (196/6,605). There was no incidence of pneumothorax due to bullae rupture. No significant difference in the incidences of pneumothorax between patients with and without bullae (0/196 vs. 2/6,409, P > 0.999) was observed. In addition, length of hospital stay, intensive care unit admission rate, and prolonged intensive care unit stay were not significantly different between the two groups. Kaplan-Meier analysis showed that there was no significant difference in lengths of hospital stay between the two groups (log-rank test, P > 0.999).

CONCLUSION

In our cohort, there was no incidence of pneumothorax following robotic prostatectomy in patients with preoperative bullae. This result could help in the management of patients with prostate cancer with bullae.

Results of the surgical treatment of pulmonary bleb and bullous disease: A retrospective study

Objective

Bullous lung disease is characterised by the development of bullae within the lung parenchyma. Smoking is considered as a main risk factor of bullae formation. The clinical manifestation varies from asymptomatic bullae to severe respiratory distress. The exact medical approach is still controversial. Here, we aimed to evaluate the patient clinical characteristics and the indication of surgery in the patients.

Methods

This study was an analytic cross-sectional study in Razi hospital, Rasht, Iran, in 2016-2020. A total of 110 patients with newly diagnosed lung bullae underwent evaluation based on a checklist, which assessed the variables as clinical characteristics, bullae features, the medical treatment, and its complication. Eventually, statistical analysis was performed by using SPSS v21.0.

Results

: A total of 110 patients were enrolled. All the patients were smokers. In 72.9%, the primary presentation was respiratory distress, which needed surgical resection with no recurrence over 8 months. The clinical manifestation varies from asymptomatic bullae in 4.3% and pneumonia in 34.3% to respiratory distress in 61.4%. There was no statistical correlation between clinical manifestation and all the studied variables excluding respiratory distress (p value: 0.659). Seventy patients underwent surgical treatment, in which 20 cases were complicated by air leak that was managed by the chest tube in 16 patients and the Heimlich valve in four patients. No evidence of recurrence was detected.

Conclusion

The main risk factor of bulla formation is smoking. Because of various clinical presentations, the appropriate medical approach is of paramount importance.

Aetiology of Primary Spontaneous Pneumothorax

Air in the pleural cavity is termed pneumothorax. When this occurs in the absence of trauma or medical intervention, it is called spontaneous pneumothorax. Primary spontaneous pneumothorax typically occurs in young patients without known lung disease. However, the idea that these patients have “normal” lungs is outdated. This article will review evidence of inflammation and respiratory bronchiolitis on surgical specimens, discuss the identification of emphysema-like change (i.e., blebs and bullae), the concept of pleural porosity and review recent data on the overexpression of matrix metalloproteinases in the lungs of patients who have had pneumothorax.

An evidence-based review of primary spontaneous pneumothorax in the adolescent population

Primary spontaneous pneumothorax (PSP) is a relatively common problem in emergency medicine. The incidence of PSP peaks in adolescence and is most common in tall, thin males. Recent advances in the care of patients with PSP have called into question traditional approaches to management. This clinical review highlights the changing management strategies for PSP and concludes with a proposed evidence-based pathway to guide the care of adolescents with PSP.

Pulmonary carcinoid presenting in pregnancy with an unusual radiological feature

Pulmonary carcinoid tumours are a rare form of malignancy that often present with clinical heterogeneity and are challenging to diagnose. Diagnosis during pregnancy is further complicated by delays in imaging and procedures to minimise harm to the fetus. This case describes a primigravid healthcare worker who was diagnosed with pulmonary carcinoid in her first trimester of pregnancy, with particular focus on the unique radiological findings of subpleural blebs as a feature.

Severity of Pectus Excavatum is a Risk Factor for Primary Spontaneous Pneumothorax

BACKGROUND AND OBJECTIVE

This study aimed to investigate the relationship between bleb formation, primary spontaneous pneumothorax (PSP) and pectus excavatum (PE).

METHODS

From July 2005 to December 2016, the records of 514 patients with PE who underwent the Nuss procedure were obtained from a prospectively collected database and reviewed. Clinical features, images and treatments were analyzed retrospectively.

RESULTS

The incidence rate of bleb formation was 26.5% in PE patients. The bleb group had a greater body height (174.4 cm vs. 170.4 cm, p < 0.001), a higher Haller index (HI; 4.2 vs. 3.43, p < 0.001) and a higher risk of developing PSP than the non-bleb group (risk ratio 9.8, p = 0.002). HI values larger than 3.615 had good discriminatory power for predicting bleb formation in patients with PE. With each increase in the HI, PE patients had a 2.2-fold greater odds ratio of bleb formation (odds ratio 2.221, CI 1.481-3.330, p < 0.001).

CONCLUSION

We discovered that a high percentage of PE patients have bleb formation and a higher risk of PSP, especially those with an HI >3.615. High-resolution computed tomography of the chest may be useful for evaluating both the HI and the presence of blebs in the lungs before performing a corrective surgical procedure.

Long-term risk of pneumothorax in asthmatic children: A 12-year population-based cohort study

Pneumothorax is a life-threatening complication during acute asthma attack. However, long-term risk of pneumothorax in asthmatic children remains unknown.In this retrospective cohort study, 333,657 children were defined as asthma cohort and a 1:1 matched non-asthma cohort were generated from 2000 to 2011. At the end of 2012, the incidence of pneumothorax in asthma and non-asthma cohorts and asthma to non-asthma hazard ratios (HRs) with confidence intervals (CIs) of pneumothorax were analyzed.The incidence of pneumothorax was 1.35-fold higher in the asthma cohort than that in the non-asthma cohort. The asthma to non-asthma HRs of pneumothorax were higher in children younger than 6 years (1.76, 95% CI: 1.21-2.57) and in girls (2.27; 95% CI: 1.23-4.16). The HRs of pneumothorax were higher in asthmatic children with more asthma-related out-patient clinic visits/per year (>5 visits; HR: 2.81; 95% CI: 1.79-4.42), more emergency department visits/per year (>4 visits; HR: 1.68; 95% CI: 1.02-2.78), and longer hospitalization days due to asthma (>4 days; HR: 3.42; 95% CI: 1.52-6.94) (P < .0001, the trend test).Asthmatic children had greater risk for pneumothorax, particularly in young children and in those with severe and uncontrolled asthma.

Pneumothorax in connective tissue disease-associated interstitial lung disease

Background

Spontaneous pneumothorax is a complication that occurs in patients with connective tissue disease-associated interstitial lung disease (CTD-ILD); however, few studies on the clinical implications of pneumothorax for patients with CTD-ILD have been performed.

Objectives

This study aimed to investigate the incidence and prognostic significance of pneumothorax and the risk factors for its onset in patients with CTD-ILD.

Methods

This study included 140 consecutive patients with CTD-ILD. Clinical characteristics, laboratory findings, pulmonary function test results, and chest high-resolution computed tomography (HRCT) images were retrospectively evaluated.

Results

A total of 18 patients (12.9%) developed pneumothorax during their clinical course. The cumulative incidence of pneumothorax from the time of CTD-ILD diagnosis was 6.5%, 8.7%, and 11.3% at 1, 3, and 5 years, respectively. The 10-year survival rate was significantly lower in patients with pneumothorax (29.6%) than that in those without pneumothorax (81.3%). The development of pneumothorax was significantly associated with poor prognosis (HR 22.0; p < 0.010). Furthermore, a lower body mass index, greater extent of reticular abnormalities on HRCT, and administration of methylprednisolone pulse therapy were significantly associated with the development of pneumothorax.

Conclusion

Pneumothorax is a serious complication in the clinical course of patients with CTD-ILD and the onset of pneumothorax predicts a poor outcome.

The Importance of Genetic Factors in the Management of Spontaneous Pneumothorax

Purpose of Review

Spontaneous pneumothoraces can be the presenting phenotype in a variety of different syndromic genetic conditions. Respiratory physicians therefore have the opportunity to diagnose and manage these patients early to prevent serious complications associated with these syndromes.

Recent Findings

The genetic syndromes that present with pneumothoraces can be split broadly between those resulting from defective extracellular matrix formation and those caused by defective tumour-suppressor pathways. When connective tissues are weakened, lifelong surveillance for arterial dilatation can be life-saving as surgical intervention is effective. Long-term aggressive treatment of blood pressure can also commence, although some controversy surrounds which drugs are most effective and precisely how these drugs modify disease progression. Rational treatments of syndromes in which tumour suppressor function is lost are being developed and, in some instances, can already be offered.

Summary

Careful clinical assessment of spontaneous pneumothorax may identify an underlying causal condition and facilitate life-saving intervention. Respiratory physicians must therefore be aware of these diseases and their diagnostic criteria.

Prevalence of Pulmonary Bullae and Blebs in Postmortem CT Imaging With Potential Implications for Diving Medicine

BACKGROUND

Pulmonary bullae and blebs can result in a pneumothorax. Their prevalence in the normal population is currently unknown. Postmortem CT (PMCT) images from a forensic database were used to determine the prevalence of pulmonary bullae/blebs in the normal Dutch adult population and its consequence for diving medicine, as bullae and blebs are often considered a contraindication for diving.

METHODS

Forensic PMCT scans of 130 adults were analyzed for the presence of bullae and/or blebs in a cross-section of the Dutch population without pulmonary disorders. The lungs had to be unharmed, expanded, and without signs of illnesses. Normal early-stage postmortem changes in the lungs were accepted.

RESULTS

Analysis was performed per decade. Group I (aged 21-30 years) included 26 patients. Blebs were observed in four persons; one exhibited blebs and bullae. Group II (aged 31-40 years) included 28 patients; blebs were observed in nine individuals, one with bullae. Group III (aged 41-50 years) included 27 patients; blebs were noted in nine individuals, bullae in one, and bullae and blebs in four. Group IV (aged 51-60 years) included 28 patients; blebs were noted in seven individuals and two with bullae and blebs. Group V (aged 61-70 years) included 21 patients; blebs were noted in three persons, bullae and blebs in two, and isolated bullae in one. On average, most bullae/blebs were < 10 mm, and none exceeded 20 mm.

CONCLUSIONS

By reassessing pulmonary PMCT scans, we found a surprisingly high incidence of small bullae and/or blebs in one-third (33.8%; 95% CI, 25.7-41.9) of the general population without underlying lung disease. This finding can have potential implications for diving medicine.

The Genetics of Pneumothorax

A genetic influence on spontaneous pneumothoraces-those occurring without a traumatic or iatrogenic cause-is supported by several lines of evidence: 1) pneumothorax can cluster in families (i.e., familial spontaneous pneumothorax), 2) mutations in the FLCN gene have been found in both familial and sporadic cases, and 3) pneumothorax is a known complication of several genetic syndromes. Herein, we review known genetic contributions to both sporadic and familial pneumothorax. We summarize the pneumothorax-associated genetic syndromes, including Birt-Hogg-Dubé syndrome, Marfan syndrome, vascular (type IV) Ehlers-Danlos syndrome, alpha-1 antitrypsin deficiency, tuberous sclerosis complex/lymphangioleiomyomatosis, Loeys-Dietz syndrome, cystic fibrosis, homocystinuria, and cutis laxa, among others. At times, pneumothorax is their herald manifestation. These syndromes have serious potential extrapulmonary complications (e.g., malignant renal tumors in Birt-Hogg-Dubé syndrome), and surveillance and/or treatment is available for most disorders; thus, establishing a diagnosis is critical. To facilitate this, we provide an algorithm to guide the clinician in discerning which cases of spontaneous pneumothorax may have a genetic or familial contribution, which cases warrant genetic testing, and which cases should prompt an evaluation by a geneticist.

The link between tuberculosis and body mass index

The evidence behind the strong correlation between reactivation of tuberculosis (TB) and low body mass index (BMI) was reviewed. This strong association between TB and BMI occurred only with pulmonary TB and not extra-pulmonary TB, indicating that a low-BMI body build may in some way predispose to TB reactivation in the lungs. A possible explanation may be the congenital apical lung bullae that occur in 15% of the population and are likely to enlarge in young low-BMI males since biomechanical modeling of pleural stress has shown a massive 40x increase in apical pleural stress in low antero-posterior (AP) diameter chests associated with a low-BMI build. This suggests that pre-existing lung cavities may predispose to TB reactivation instead of current thinking that cavitation occurs after reactivation. Supporting this hypothesis is the relatively common incidence of both TB and primary spontaneous pneumothorax (PSP) occurring simultaneously. Furthermore, this hypothesis also gives a potential explanation for the apical location of secondary TB in the lower lobe as the conventional explanations of high apical oxygen levels and gravity appear to be invalid for the lower lobe. This opens up the possibility of a clinical trial that low-dose computerized tomography (CT) may be used to screen for the presence of subclinical apical bullae in low-BMI, high TB risk cohorts.

Imaging in noncardiovascular thoracic emergencies: a pictorial review

Cardiovascular and noncardiovascular conditions are commonly encountered in the emergency department. While the majority of patients have underlying cardiovascular aetiologies, such as acute myocardial infarction, congestive heart failure, aortic dissection and pulmonary embolism, a small subset of patients have underlying noncardiovascular conditions, although they present with similar symptoms of chest pain, dyspnoea, cough, haemoptysis and haematemesis. This article aims to describe the imaging findings in common noncardiovascular conditions of the chest that are frequently encountered in the emergency department, with a review of the existing literature.

Is it possible to standardize the treatment of primary spontaneous pneumothorax? Part 1: etiology, symptoms, diagnostics, minimally invasive treatment

The authors of this report present the history of primary spontaneous pneumothorax (PSP) treatment, its etiology, clinical symptoms, and diagnostic methodology. Further, they discuss minimally invasive methods of treating PSP such as thoracentesis and chemical pleurodesis. They discuss the pros and cons of each method, emphasizing that, according to the international recommendations, they should be used as the first line of treatment for PSP.

A biomechanical hypothesis for the pathophysiology of apical lung disease

OBJECTIVE

A hypothesis is presented suggesting that the pathogenesis of apical lung disease is due to progression of subclinical congenital apical bullae in people with low Body Mass Index (BMI), a combination present in 15% of the population, due to high pleural stress levels present in the antero-posteriorly flattened chests of these individuals.

DESIGN

The hypothesis was tested for validity in two apical lung pathologies with widespread epidemiological literature, namely tuberculosis (TB) and primary spontaneous pneumothorax (PSP), assessing whether the hypothesis could identify high-risk populations, explain exceptional cases like apical lower lobe disease and confirm predictions.

RESULTS

The biomechanical hypothesis can explain the high-risk factors of apical location, age, gender and low-BMI build, as well as the occurrence of disease in the apex of the lower lobe, in both TB and PSP patients. A predicted common pathogenesis for apical lung disease was confirmed by the higher-than-expected incidence of concomitant TB and PSP.

CONCLUSION

Pleural stress levels depend on chest wall shape, but are highest in the apex of young males with low BMI, leading to growth of congenital bullae that can eventually limit clearance inhaled material, superinfect or burst. This hypothesis suggests that low-dose computerized tomography may be used to screen for TB eradication. This paper is the first to propose a biomechanical mechanism for all apical lung disease pathophysiology.

Spontaneous pneumothorax: time to rethink management?

There are substantial differences in international guidelines for the management of pneumothorax and much geographical variation in clinical practice. These discrepancies have, in part, been driven by a paucity of high-quality evidence. Advances in diagnostic techniques have increasingly allowed the identification of lung abnormalities in patients previously labelled as having primary spontaneous pneumothorax, a group in whom recommended management differs from those with clinically apparent lung disease. Pathophysiological mechanisms underlying pneumothorax are now better understood and this may have implications for clinical management. Risk stratification of patients at baseline could help to identify subgroups at higher risk of recurrent pneumothorax who would benefit from early intervention to prevent recurrence. Further research into the roles of conservative management, Heimlich valves, digital air-leak monitoring, and pleurodesis at first presentation might lead to an increase in their use in the future.

A hypothesis for reactivation of pulmonary tuberculosis: How thoracic wall shape affects the epidemiology of tuberculosis

This study was aimed at determining the cause for the high incidence of tuberculosis (TB) reactivation occurring in males with a low body mass index (BMI). Current thinking about pulmonary TB describes infection in the lung apex resulting in cavitation after reactivation. A different hypothesis is put forward for TB infection, suggesting that this occurs in subclinical apical cavities caused by increased pleural stress due to a low BMI body habitus. A finite element analysis (FEA) model of a lung was constructed including indentations for the first rib guided by paramedian sagittal CT reconstructions, and simulations were conducted with varying antero-posterior (AP) diameters to mimic chests with a different thoracic index (ratio of AP to the transverse chest diameters). A Pubmed search was conducted about gender and thoracic index, and the effects of BMI on TB. FEA modeling revealed a tenfold increase in stress levels at the lung apex in low BMI chests, and a four-fold increase with a low thoracic index, r(2)  = 0.9748 P < 0.001. Low thoracic index was related to BMI, P = 0.001. The mean thoracic index was statistically significantly lower in males, P = 0.001, and increased with age in both genders. This article is the first to suggest a possible mechanism linking pulmonary TB reactivation to low BMI due to the flattened thoracic wall shape of young male adults. The low thoracic index in young males may promote TB reactivation due to tissue destruction in the lung apex from high pleural stress levels.

[Respiratory manifestations of Marfan's syndrome]

Marfan's syndrome is a rare genetic disorder caused by a mutation of the gene FBN1, coding for the protein fibrillin-1. Cardiovascular, musculoskeletal and ophthalmic manifestations are the most commonly observed, but minor diagnostic criteria also include pulmonary manifestations. Pneumothorax, frequently relapsing, affects 5 to 11% of patients. Rib cage abnormalities (pectus excavatum or pectus carinatum) and apical blebs may contribute to their occurrence. Treatment does not require any specific procedure but there is an increased risk of recurrence. Pectus excavatum affects up to 60% of the patients, without any functional impairment in most cases. Surgery may be required (using the Nuss procedure) in case of cardiovascular or psychological symptoms. Marfan's syndrome is frequently associated with obstructive sleep apnoea, which may itself contribute to aortic dilatation. Some studies suggest a potential role of craniofacial abnormalities in the pathogenesis of sleep apnea in these patients. Pulmonologists should consider Marfan's syndrome when treating patients for recurrent spontaneous pneumothorax or rib cage abnormalities, since early detection of cardiac abnormalities improves the prognosis significantly.

Pneumothorax from subpleural blebs-a new association of sotos syndrome?

We describe two unrelated patients with molecularly confirmed Sotos syndrome with multiple subpleural blebs and pneumothorax. We propose this as a new association. Patient 1 is a 3-year-old boy with a 1.9 Mb interstitial deletion of the long arm of chromosome 5, with breakpoints at q35.2 and q35.3, encompassing NSD1 and Patient 2 is a 9-year-old girl with a de novo truncating mutation within NSD1. Both patients presented with sudden onset dyspnea due to a unilateral pneumothorax: Patient 1 at the age of 18 months and Patient 2 at 9 years. In both, the pneumothorax recurred following removal of the chest drain and, on further investigations, multiple subpleural blebs were identified necessitating a pleurodesis and tissue resection. This is the first report of multiple subpleural blebs leading to pneumothorax in association with Sotos syndrome. Given the similar and unusual presentation in the two affected patients, we suggest that this may be a real association, albeit a rare one. While screening would not be advocated for such a rare association, we recommend that clinicians consider pneumothorax in patients with Sotos syndrome and sudden onset of dyspnea and are aware that it may be refractory to first line treatment.

Advances in the management of pleural disease

Pleural disease affects over 3000 people per million population annually. Consequently, it represents a significant proportion of the respiratory physician's workload and can present to clinicians of all backgrounds in primary and secondary care. Pleural effusions have been reported in association with over 50 different conditions; some related to specific pulmonary pathologies, but many being manifestations of multisystem disease. The burden that conditions such as pleural infection; malignant pleural disease; and pneumothorax impose on patients and health care systems is enormous and growing. As such, a clear understanding of these key conditions is crucial to any physician regardless of the specialty. This article addresses a number of areas relating to pleural disease, providing an overview of the diagnostic and therapeutic advances that have been made in our understanding of pleural pathology in recent years. The directions that future research in this important area of respiratory medicine might take will also be discussed.

Diagnosis and treatment of patients with spontaneous pneumomediastinum

BACKGROUND

Although many patients complaining of chest pain visit the emergency department, very few are diagnosed with spontaneous pneumomediastinum (SPM). We present the management of 20 patients with SPM.

METHODS

We retrospectively analyzed the clinical features, past history, chest X-rays (CXRs), 64-slice helical computed tomography (CT) images, and clinical course of 20 patients with SPM (19 men and 1 woman) who visited the emergency department of the Tokyo Metropolitan Bokutoh Hospital between 2005 and 2010.

RESULTS

SPM predominantly resulted from physical exertion during such activities as sports and weight lifting (8 patients). The most common complaint was chest pain (15 patients), followed by dysphagia (10 patients), and dyspnea (8 patients). Subcutaneous emphysema was detected in 9 patients. The mean body mass index of the patients was 20.8±1.4kg/m(2). Although CXR findings of pneumomediastinum were absent in 5 patients, CT showed findings of the Macklin effect in all patients-interstitial gas was observed in the perihilar area in all patients and in the peripheral lung area in 9 patients (45%). Ten patients were hospitalized. The others received ambulatory care in the form of analgesics without antibiotics. All patients fully recovered without complications.

CONCLUSIONS

Our results showed that 64-slice helical CT is more reliable than CXRs for diagnosing SPM. Moreover, some patients with SPM can be treated without hospitalization, thus decreasing medical expenses for these patients.

Technical difficulties and complications of sympathectomy in the treatment of hyperhidrosis: an analysis of 1731 cases

BACKGROUND

The aim of this study was to ascertain the technical difficulties and complications of video-assisted thoracic sympathectomy (VTAS) in the treatment of hyperhidrosis in a large group of patients.

METHODS

Between October 1995 and February 2008, 1731 patients with palmar, axillary, or craniofacial hyperhidrosis, who were treated using bilateral VTAS, were studied. We assessed the technical difficulties, early and late complications, and the approaches that were used to resolve them.

RESULTS

Therapeutic success was achieved in 91% of the cases as evidenced by anhidrosis. The most common and severe technical difficulty during the procedure was pleural adhesions in 116 cases (6.7%); azygos lobes were seen in 7 patients (0.4%) and apical blebs in 3 patients (0.2%). The most frequent postoperative immediate complication was postoperative pain in 1685 (97.4%) patients; pneumothorax with chest drainage was seen in 60 cases (3.5%), neurologic disorders involving the upper limbs in 36 cases (2.1%), Horner's syndrome in 11 cases (0.9%), significant bleeding in 8 cases (0.4%), and 1 patient had extensive subcutaneous emphysema. The most frequent late complication was compensatory hyperhidrosis, which occurred in 1531 cases (88.4%). Although 27.2% of the patients reported severe compensatory hyperhidrosis, only 2.5% expressed regret for undergoing surgery. Gustatory sweating occurred in 334 patients (19.3%). No deaths occurred in this series.

CONCLUSIONS

VTAS is safe and has shown good results. The major complication is compensatory hyperhidrosis and, when severe, the patient may express regret for undergoing surgery. Improvements in instrumentation, adequate training, and careful patient selection may help to reduce the number of drawbacks associated with VTAS.

A unique, histopathologic lesion in a subset of patients with spontaneous pneumothorax

CONTEXT

Spontaneous pneumothorax can be idiopathic (primary), or it can occur in association with an underlying predisposing condition (secondary). Spontaneous pneumothorax may be a harbinger of an undiagnosed clinical condition, which may be associated with serious systemic abnormalities, making early recognition and diagnosis important. The pulmonary pathology of some of these disorders has not been fully elucidated.

OBJECTIVE

To review cases of pneumothorax in the hope of identifying pathologic features that might correlate to specific clinical syndromes.

DESIGN

The pathology computer files at 3 hospitals were searched for all cases of spontaneous pneumothorax, primary and secondary, regardless of etiology during a 11-year period. Ninety-two cases were retrieved. Each of the cases was evaluated for reactive eosinophilic pleuritis, elastosis, pleural fibrosis, emphysema, intra-alveolar macrophages, cholesterol clefts, vasculopathy, and intraparenchymal or intrapleural cysts. Clinical information regarding asthma and smoking history, site of the pneumothorax, family history, radiographic findings, predisposing conditions, recurrence, age, and sex were extracted from the medical records.

RESULTS

In 11 patients (12% of all the patients with spontaneous pneumothorax), a distinctive pattern of pleural fibrosis with islands of fibroblastic foci within a myxoid stroma was noted at the pleural-parenchymal interface or leading edge. These lesions correlated with a select subset of patients, consisting predominantly of young men.

CONCLUSIONS

Our review identified a distinct pattern of pneumothorax-associated fibroblastic lesions in a subset of cases of spontaneous pneumothorax. Whether this is related to the pathogenesis of the pneumothorax remains to be elucidated.

On the Stability of Lung Parenchymal Lesions with Applications to Early Pneumothorax Diagnosis

Spontaneous pneumothorax, a prevalent medical challenge in most trauma cases, is a form of sudden lung collapse closely associated with risk factors such as lung cancer and emphysema. Our work seeks to explore and quantify the currently unknown pathological factors underlying lesion rupture in pneumothorax through biomechanical modeling. We hypothesized that lesion instability is closely associated with elastodynamic strain of the pleural membrane from pulsatile air flow and collagen-elastin dynamics. Based on the principles of continuum mechanics and fluid-structure interaction, our proposed model coupled isotropic tissue deformation with pressure from pulsatile air motion and the pleural fluid. Next, we derived mathematical instability criteria for our ordinary differential equation system and then translated these mathematical instabilities to physically relevant structural instabilities via the incorporation of a finite energy limiter. The introduction of novel biomechanical descriptions for collagen-elastin dynamics allowed us to demonstrate that changes in the protein structure can lead to a transition from stable to unstable domains in the material parameter space for a general lesion. This result allowed us to create a novel streamlined algorithm for detecting material instabilities in transient lung CT scan data via analyzing deformations in a local tissue boundary.

Laparoscopic retroperitoneal/mesenteric lymph node sampling: a safe and effective technique

INTRODUCTION

Needle aspiration and core biopsies are commonly used to assess retroperitoneal lymph nodes. However, the tissue obtained by this method is insufficient to define and type the tumour. This article demonstrates the feasibility and safety of the laparoscopic approach in obtaining an adequate volume of lymph node tissue for typing.

METHODS

Laparoscopic retroperitoneal lymph node biopsy was performed on 12 patients over a period of five years. A pneumoperitoneum was induced with a Veress needle, and an initial 10-mm trocar was inserted in the sub-umbilical region in order to carry a 30-degree telescope. Two or more 5-mm ports were inserted into the targeted areas under laparoscopic guidance to achieve optimal triangulation in order to access the nodal tissue.

RESULTS

The procedure was successful in 11 out of the 12 patients. An average volume of 1.7 cm3 of tissue was harvested for each patient. In one patient with preoperatively undiagnosed portal hypertension, laparoscopy was converted to an open procedure due to bleeding. In all patients, the histology was adequate and contributed to the diagnosis, allowing rapid institution of treatment. The diagnosis was reactive lymphadenopathy in three patients and sarcoidosis in one patient. Seven others suffered from various conditions, including lymphoma, leukaemia, secondary from unknown origin and Castleman's disease.

CONCLUSION

Laparoscopy allows access to perihepatic and perisplenic areas, and is a procedure of choice when needle biopsy is not possible or fails to provide an adequate sample.

Primary spontaneous pneumothorax: a diffuse disease of the pleura

Primary spontaneous pneumothorax (PSP) is by definition not associated with any underlying lung disease. However, this does not mean that there is no underlying pathological process. It has become increasingly apparent over recent years that PSP is associated with diffuse and often bilateral abnormalities within the pleura and is not simply a disease caused by ruptured blebs/bullae. The pathological process includes emphysema-like changes, pleural porosity and inflammation. In this review, we summarise the recent advances in our understanding of the pathogenesis of PSP and discuss how this relates to management strategies for patients with PSP.

Pleural controversy: aetiology of pneumothorax

Pneumothoraces are classified as spontaneous, traumatic and iatrogenic. Spontaneous pneumothoraces that occur without recognized lung disease are termed primary spontaneous pneumothoraces (PSP), whereas those that occur due to an underlying lung disease are termed secondary spontaneous pneumothoraces. The aetiology of secondary, traumatic or iatrogenic pneumothoraces is not usually debated. However, the aetiology of PSP is potentially controversial and often debated. Therefore, PSP is the focus of this article. There are several purported causes, which include blebs, bullae, emphysema-like changes (ELC) and pleural porosity. The controversy is valid because of the importance of recurrence prevention. This article reviews the current available evidence for the causes of PSP. The causes of PSP are likely a combination ELC, pleural porosity and other potential factors.

Frequency of undiagnosed cystic lung disease in patients with sporadic renal angiomyolipomas

OBJECTIVE

The aim of this study was to assess the frequency of undiagnosed cystic lung lesions suggestive of pulmonary lymphangioleiomyomatosis (LAM) in patients who received a diagnosis of sporadic renal angiomyolipomas (AMLs).

METHODS

We conducted a retrospective review of CT scans of the chest or abdomen for cystic lung lesions on 176 adult patients who received a diagnosis of sporadic renal AML during a 10-year period, 1997 to 2006, and comparison with chest CT scans of 176 control subjects without renal AML but matched for age, sex, and smoking history. Patients presenting with suspected or known pulmonary LAM and those with underlying tuberous sclerosis were excluded.

RESULTS

Sporadic renal AML was diagnosed in 176 patients with a median age of 58 years (range, 20-91 years), the majority of whom were women (81.8%). Renal tumor was an incidental finding on imaging studies for most patients (90.3%). Nineteen patients (10.8%) had one or more cystic lung lesions and included nine patients (5.1%) with four or more cysts, all of whom were women. In comparison, eight control subjects (4.6%) had one to three cystic lung lesions and none of them exhibited four or more cysts. None of the patients with renal AML and cystic lung lesions, including six women with 10 or more cysts, had undergone an evaluation of their cystic lung disease.

CONCLUSIONS

We conclude that a significant portion of women with sporadic renal AMLs exhibit cystic lung lesions suggestive of pulmonary LAM but may remain undiagnosed. Coexistence of pulmonary LAM should be considered in women incidentally found to have sporadic renal AMLs.

Pneumothorax and bullae in Marfan syndrome

BACKGROUND

Increased risk of spontaneous pneumothorax has been described in patients with Marfan syndrome and has been attributed, in part, to the presence of apical blebs and bullae.

OBJECTIVES

We assess the risk of pneumothorax and its relationship to the presence of apical blebs and bullae in patients with Marfan syndrome in the era of CT imaging.

METHODS

A retrospective cohort study was performed of all patients 13 years or older with Marfan syndrome evaluated at the Mayo Clinic, Rochester, Minn., USA, from 1998 through 2008. One hundred and sixty-six patients met the current diagnostic criteria for Marfan syndrome and had chest imaging studies available for review.

RESULTS

The median age was 40 years (range 14-71); 37% had a smoking history. Eight of 166 patients (4.8%) had experienced 1 or more episodes of spontaneous pneumothorax, and 2 of these 8 patients had 2 or more episodes. Apical blebs or bullae were identified on radiologic imaging in 16 patients (9.6%). Four of 16 (25%) patients with apical blebs or bullae had a history of spontaneous pneumothorax compared to 4 of 150 patients (2.7%) without blebs or bullae (p = 0.003).

CONCLUSIONS

The frequency of blebs is relatively low in patients with Marfan syndrome but the risk of pneumothorax is significantly higher in those with radiologically detectable blebs or bullae. Chest CT scanning to identify blebs and bullae may allow risk stratification for pneumothorax in patients with Marfan syndrome.

Review: Diagnosis and treatment of primary spontaneous pneumothorax

Primary spontaneous pneumothorax (PSP) commonly occurs in tall, thin, adolescent men. Though the pathogenesis of PSP has been gradually uncovered, there is still a lack of consensus in the diagnostic approach and treatment strategies for this disorder. Herein, the literature is reviewed concerning mechanisms and personal clinical experience with PSP. The chest computed tomography (CT) has been more commonly used than before to help understand the pathogenesis of PSP and plan further management strategies. The development of video-assisted thoracoscopic surgery (VATS) has changed the profiles of management strategies of PSP due to its minimal invasiveness and high effectiveness for patients with these diseases.