Chromatic confocal microscopy with a finite pinhole size.

Chromatic confocal microscopy has the advantage of short measurement times because of its parallel depth scan. As most white-light sources have limited optical output power, light-efficient setups are necessary. Using an extended detection pinhole is one way to improve light efficiency. We have calculated the effect of extended pinholes in chromatic confocal setups. We found that, for certain pinhole sizes, the FWHM of the confocal signal is nearly constant over a large wavelength interval.

Signal evaluation for high-speed confocal measurements.

The confocal-detection principle is open especially for use in medical applications. For inspection systems applications for technical objects in reflection confocal setups are of growing importance. For such applications the confocal measurements need to have a very short measuring time. A fast detection system is needed and to satisfy this requirement only a small number of height levels are measured and a fast-evaluation algorithm is used. Drawbacks of the reduction of height levels are a greater influence of noise and additional systematic errors on the measured heights. Study the effects of the reduction are calculated, different evaluation algorithms are analyzed, and the optimization of the parameters is discussed.

Aberration measurement from confocal axial intensity response using neural network.

We propose a high-speed, parallel system for lens aberration measurement employing a confocal optical setup. This method uses a non-interferometric, conventional confocal axial response to determine the spherical aberration coefficient of a confocal objective. The aberration coefficients are successfully calculated from the intensity axial response by employing a neural network. It is estimated that the system can find out the aberration coefficients of 10,000 microlenses in 20 seconds of measurement and 1 second of calculation time. Our experimental results also demonstrate the practicality of this system.

[Severe hypoxemia with orthodeoxia due to right to left shunt in idiopathic bronchiolitis obliterans organizing pneumonia]. / Hypoxémie sévère avec orthodéoxie par shunt droit-gauche au cours d'une bronchiolite oblitérante avec organisation pneumonique idiopathique.

We report a case of BOOP with severe hypoxemia and orthodeoxia. Chest X-ray showed bilateral infiltrative pneumonia and computed tomography scan revealed consolidations on lower lobes. Diagnosis of right-to-left shunt was made on the increase of alveolar-arterial oxygen difference under FIO2 100%, accented in standing position. Contrast-enhanced echocardiography and technetium-99 macroaggregated albumin body scanning did not show anatomical right-to-left shunt and permitted the diagnosis of intrapulmonary shunt at the capillary level because of intra-alveolar organisation. Treatment with corticosteroids and cyclophosphamide led to clinical, and radiological improvement with correction of the hypoxemia and the shunt.

Self-expanding metal stents for the management of bronchial stenosis and bronchomalacia after lung transplantation.

BACKGROUND: Airway stenosis or malacia after lung transplantation, usually as a result of anastomotic ischemia, remains a major problem. METHODS: The authors report their experience with the Gianturco expandable stent for the management of 23 bronchial stenoses in 18 patients following lung transplantation. Stent placement occurred an average of 5.6 months after transplantation. RESULTS: Stents were well tolerated and produced immediate symptomatic and functional improvement. The mean follow-up after implantation was 21 months (range, 4 to 48 mo). The authors removed five stents by endoscopy and replaced them, and removed one stent entirely. Laser resection was used to control granulomas or partial fibrosis stenosis that occurred in four stents (14.3%) after an average of 4 months. One stent broke but was still in place and effective 32 months later. One patient died of hemorrhage 4 months after stenting. CONCLUSION: Although it can still be improved, this expandable metal stent is suitable for the treatment of posttransplantation proximal bronchial stenosis.

Late resolution of hepatopulmonary syndrome after liver transplantation.

We report a 38-year-old patient with hepatopulmonary syndrome related to posthepatitis C liver cirrhosis. After liver transplantation, hypoxemia initially worsened markedly, then resolved completely 14 months after transplantation. Liver transplantation may be a reliable treatment of hepatopulmonary syndrome, but clinicians should be aware that the correction of hypoxemia may be delayed and that transient deterioration is possible.

[Radiation tolerance of patients after pneumonectomy for bronchial cancer: role of pulmonary function tests]. / Tolérance à l'irradiation des patients ayant eu une pneumonectomie pour cancer bronchique: place de l'exploration fonctionnelle respiratoire.

Radiation is often necessary after pneumonectomy, either immediately or due to local cancer recurrence. High radiation doses represent a challenge due to the limited tolerance of the lung and the necessity of preserving and protecting the remaining lung parenchyma. The use of CT scan based-treatment planning allows delivery of high radiation doses. To evaluate the radiation tolerance of the lung after high radiation dose, we compared pulmonary function tests performed before surgery and after radiation therapy. Ten male patients (mean age, 56 years old; age range, 45-73) were irradiated after pneumonectomy for lung cancer. All patients had a CT scan-based treatment planning. The mean radiation dose was 56 Gy (45-66 Gy) delivered with a linear accelerator and multiple complex fields. Two or more sets of pulmonary function tests were available (before surgery and 2 to 6 months after radiation). No patient developed clinical radiation pneumonitis and most of the patients had a minimal paramediastinal fibrosis at CT scan. Postirradiation pulmonary lung tests were compared to the theoretical values of the estimated defect observed after pneumonectomy. No significant decrease in forced expiratory volume in 1 s/inspiratory vital capacity (FEV1/IVC) was observed in ten evaluable patients; the observed values were comparable to those expected after pneumonectomy without irradiation (FEV1/IVC: 61 to 100%), showing that irradiation did not alter pulmonary function. Computerized tomography-based treatment planning and the use of complex beam positioning allowed optimal lung parenchymal preservation. Through this procedure, high doses of radiation can be delivered to the mediastinum and bed tumor. Comparison of pulmonary function tests performed before surgery and after radiation showed no alteration of lung function, even after high doses. Optimal tools required for the evaluation of radiation on lung parenchyma are still to be defined.

Thin-section CT detection of emphysema associated with bronchiectasis and correlation with pulmonary function tests.

PURPOSE: To evaluate, on thin-section CT scans, the prevalence of emphysema in patients with bronchiectasis and to correlate the results of thin-section CT scans with the results of pulmonary function tests, in order to question whether there was a particular functional test profile in this group of patients. PATIENTS AND METHODS: This is a retrospective study including 90 patients having both thin-section CT scans and pulmonary function tests for bronchiectasis. A CT scoring system was established for assessing the airway disease by the severity and extent of bronchiectasis and by the extent of emphysema. CT scans were reviewed independently by two reviewers and final interpretation was obtained by consensus. Results of thin-section CT scans were correlated with results of pulmonary function tests, including FEV1 and FEV1/FVC to assess air-way obstruction, total lung capacity and residual volume to assess air trapping, and diffusing capacity for carbon monoxide/alveolar volume (DCO/VA). RESULTS: CT evidence of emphysema, which was noted in 45% of the patients (n = 41), was mainly localized in the same bronchopulmonary segments as bronchiectasis. The presence of emphysema was in relation to the extent and to the severity of bronchiectasis. Only eight patients with CT evidence of emphysema had functional evidence of emphysema (20%). When comparing the group of patients with CT evidence of emphysema with the group of patients with no CT evidence of emphysema, the group of patients with CT evidence of emphysema had significantly higher airflow obstruction and air trapping, had significantly lesser value of diffusing capacity, but with no decreased gas transfer (DCO/VA > 80%). CONCLUSION: Our series suggests that there is a high prevalence of emphysema in patients with bronchiectasis. Emphysema that was not suggested using pulmonary function tests in most of the cases could explain in part the higher airway obstruction observed in the group of patients with CT evidence of emphysema. This study could support the suggestive notion that emphysema, which was mainly localized in bronchiectatic lobes, could be due to the inflammatory airway process.

Post-transplant obstructive lung disease ("bronchiolitis obliterans"): a clinical comparative study of bone marrow and lung transplant patients.

Patients at a single pulmonary centre who developed obstructive lung disease after bone marrow transplantation (BMT) and lung transplantation (LT) were studied, in order to compare the clinical expression of post-transplant obstructive lung disease (PTOLD) (bronchiolitis obliterans) in these two conditions, which have so far been studied separately. Nine out of 179 patients surviving more than 100 days after BMT (5%) and 9 out of 44 patients surviving more than 100 days after LT (20%) developed post-transplant obstructive lung disease. This was defined by an irreversible airflow obstruction, as characterized by a forced expiratory volume in one second divided by forced vital capacity (FEV1/FVC) of less than 70%, and a FEV1 of less than 70% of predicted value. The mean interval between transplantation and the diagnosis of post-transplant obstructive lung disease was 262 days and 217 days for BMT and LT patients, respectively. In all cases, pulmonary symptoms consisted of dyspnoea and progressively productive cough. Bronchial dilatation on high-resolution computed tomography scans was the main imaging feature present in both groups of patients at the onset of post-transplant obstructive lung disease. The mean FEV1/FVC ratio was 51 and 54% for BMT and LT patients, respectively. All BMT and LT patients had normal transfer coefficient. Clinical chronic graft-versus-host disease was present in all BMT patients before or concurrent with the onset of post-transplant obstructive lung disease, and all LT patients had presented at least one episode of acute lung rejection.(ABSTRACT TRUNCATED AT 250 WORDS)

Bronchiectasis detected with thin-section CT as a predictor of chronic lung allograft rejection.

PURPOSE: To evaluate bronchiectasis detected with thin-section computed tomography (CT) as a potential early finding of chronic lung allograft rejection. MATERIALS AND METHODS: Forty patients were studied at least 6 months after transplantation. Follow-up CT scans were obtained 6-48 months after transplantation and were retrospectively reviewed for evidence and anatomic extent of bronchiectasis. Irreversible dysfunction of the lung transplant, called the bronchiolitis obliterans syndrome (BOS), was staged according to pulmonary function testing. Pathologic proof of bronchiolitis obliterans was obtained. RESULTS: BOS occurred in 14 (35%) of the 40 patients. When considering bronchiectasis preceding BOS, bronchiectasis was a predictor of chronic rejection with a sensitivity of 14%, a specificity of 77%, a positive predictive value of 25%, and a negative predictive value of 63%. Bronchiectasis appeared concomitantly with BOS in eight (67%) of 12 patients. CONCLUSION: The diagnosis of chronic rejection relies on the degree of impairment of pulmonary function. When the diagnosis is only suspected on the basis of minimal impairment, CT can aid in the diagnosis of rejection by depicting early pulmonary changes.

[Bilateral diaphragmatic paralysis, the cause of acute insufficiency in chronic obstructive bronchopathy. The value of nasal mechanical ventilation]. / Paralysie diaphragmatique bilatérale, cause de décompensation aiguë d'une bronchopathie chronique obstructive. Intérêt de la ventilation mécanique par voie nasale.

A 57 year old man with chronic bronchitis sought a consultation for dyspnoea at rest associated with an absolute inability to lie flat. Examination revealed paradoxical respiration and respiratory function testing revealed a mixed ventilation disturbance, which was predominantly obstructive and was aggravated in the dorsal decubitus position. Radiology revealed bilateral diaphragmatic paralysis, which was confirmed on measurement of transdiaphragmatic pressure. The patient benefited from assisted ventilation by the nasal route with an excellent result in both the short and the medium term. Investigation into the cause was negative, in particular there was no evidence of any neuromuscular abnormality. This case recalls the role of the diaphragm in acute respiratory failure and shows the value of mechanical ventilation by the nasal route in the treatment of certain types of diaphragmatic paralysis.

[Bronchiolitis obliterans with severe obstructive ventilation disorder after a bone marrow transplant. Study of 7 cases]. / Bronchiolite oblitérante avec trouble ventilatoire obstructif sévère après allogreffe de moelle osseuse. Etude de 7 cas.

In 40 to 60% of bone marrow grafts there are pulmonary complications of which the most frequent is the occurrence of an interstitial pneumonia. We report 7 cases here of a more rare complication, that of bronchiolitis obliterans (BO). Between December 1979 and November 1989, 7 patients (3.4% of our cases of GMO) have developed over several months a chronic obstructive respiratory failure (a mean VEMS of 43% of the theoretical value) in the year following the transplantation (mean delay 190 days). 6 patients presented with cutaneous, digestive or hepatic signs of chronic graft v host illness (GVH) whereas the prevalence of this complication in the population studied was 17%. Treatment combining bronchodilators and immunosuppressants was only successful in 2 cases and the outcome was fatal in the 5 other cases as a result of respiratory failure (mean delay 208 days between the appearance of respiratory symptoms and death). The pathogenesis of BO after GMO remains poorly understood. It may rest on an immune process during the course of which the BO would be the result of a chronic pulmonary GVH. Another hypothesis is that the state of the immunosuppression in these patients would favour the appearance of a bronchiolitis of an infectious origin, particularly viral. The prognosis of BO after GMO is very poor and in the absence of specific effective treatment the therapeutic strategy remains essentially that of prevention by the early detection of respiratory anomalies.

[Alveolar proteinosis. Prolonged favorable course after total pulmonary lavage]. / Protéinose alvéolaire. Evolution favorable prolongée après lavage pulmonaire total.

We report the outcome in a case of alveolar proteinosis diagnosed histologically in a 43 year old female. The increase in dyspnoea and the deterioration in the pulmonary function tests have lead to the realisation that a total pulmonary lavage was required under general anaesthesia. This was performed in two stages. A biochemical analysis of the lavage liquid showed an accumulation of phospholipids, proteins, and LDH. A subjective improvement was obtained in a few weeks followed by a slow radiological improvement as well as on CT scanning, and in respiratory function. Radiological and blood gas improvement was noted 19 months after total bilateral pulmonary lavage. Broncho-alveolar lavage is thus able to induce long-term improvement in pulmonary alveolar proteinosis.

[Pulmonary arteriovenous fistula. Apropos of 12 cases]. / Fistules artério-veineuses pulmonaires. A propos de 12 cas.

Arteriovenous fistula of the lung is a relatively rare lesion with various clinical manifestations. It may be clinically silent and discovered by chance on X-ray films of the chest or during evaluation of Rendu-Osler-Weber disease with which it is associated in about one-half of the cases. It may also have loud manifestations when complicated. The fistula is diagnosed in successive steps, mainly by respiratory function tests and pulmonary angiography. Conservative treatment should be the rule, especially in case with multiple fistulae, but it must begin at an early stage to avoid the dramatic complications of this abnormality, such as acute neurological disorders, haemoptysis, haemothorax, etc. Wide and crippling lung resection must be avoided. Aneurysmorrhaphy or embolization is sufficient to cure most of these multiple angiomas. The results obtained are measured by calculating the blood flow rate in the shunt, as it should theoretically disappear after surgery.

Gallium-67 scanning in the staging of cryptogenetic fibrosing alveolitis and hypersensitivity pneumonitis.

Gallium-67 citrate is known to localize within inflammatory sites. Gallium-67 scanning is used for the evaluation of lung inflammation (i.e. alveolitis) during interstitial lung diseases. We investigated 27 patients with cryptogenetic fibrosing alveolitis (n = 17) and hypersensitivity pneumonitis (n = 10) using gallium-67 lung scanning and lung function tests (forced vital capacity, diffusing capacity, resting and exercise blood gases). Investigations were performed before and after one year of methylprednisolone treatment. None of eight healthy volunteers had any abnormal gallium-67 uptake. In all patients with cryptogenetic fibrosing alveolitis an initial abnormal gallium-67 uptake was observed (mean fixation index: 163 +/- 18). In addition, analysis of lung function tests a year after initial evaluation showed that unchanged or improving patients presented initially with a lower gallium-67 index than patients with evidence of deterioration (153.9 +/- 23.7 vs 251.0 +/- 23.3.; p less than 0.01). Similarly, among patients with hypersensitivity pneumonitis the index was lower in unchanged or improving patients than in those with deterioration (74.9 +/- 22 vs 226.7 +/- 4.9; p less than 0.05). Thus gallium-67 scanning is useful in the management of cryptogenetic fibrosing alveolitis and hypersensitivity pneumonitis.

[Spontaneous recurrent pneumothorax in young patients. Treatment by bilateral one stage apical pleurectomy by axillary approach]. / Pneumothorax spontané et récidivant du sujet jeune. Traitement par pleurectomie apicale bilatérale en un temps par voie axillaire.

The quality of the surgical and respiratory functional results of one-stage bilateral apical pleurectomy for alternating or successive bilateral pneumothorax was evaluated in 30 patients operated upon from 1970 to 1984. These 4 women and 26 men represented 15% of the 194 patients surgically treated for pneumothorax during the same period. Among early results figure absence of mortality, moderate blood loss (295 +/- 130 ml) and short stay in hospital (11 +/- 3 days). Late results could be assessed in 23 patients with a mean post-operative follow-up of 50 +/- 21 months; 7 patients were lost sight of. No clinical or radiological recurrence of pneumothorax was observed. No dyspnoea associated by post-operative ventilatory restriction was demonstrated in our 23 patients. Among the 12 patients subjected to a total of 16 spirographic examinations, 4 out of 10 examined after 6 months showed slight restriction. These good functional results are confirmed by the literature which only gives the results of unilateral pleurectomy.