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M Kohlhäufl

Publications and source records attributed to M Kohlhäufl.

36 records · Page 2Linked to original sources
PubMed2000

Aerosol morphometry and aerosol bolus dispersion in patients with CT-determined combined pulmonary emphysema and lung fibrosis.

The simultaneous occurrence of pulmonary fibrosis and emphysema may present considerable problems in clinical assessment. Recent studies have shown that Aerosol Derived Airway Morphometry (ADAM) and Aerosol Bolus Dispersion (ABD) are changed in patients with pulmonary emphysema. This study was performed to assess the effect of simultaneous lung fibrosis in patients with emphysema on ADAM and ABD. ADAM and ABD measurements were performed in 20 patients with lone high resolution CT scan (HRCT) confirmed emphysema (E), and compared to those in 15 emphysematics with HRCT-confirmed superimposed pulmonary fibrosis (FE). In both groups the peripheral effective airspace dimension (EAD) (E: 0.63 +/- 0.20 mm; FE: 0.60 +/- 0.27 mm, N.S.) was increased by more than a factor of two compared to that of healthy subjects (0.28 +/- 0.05 mm) (p < 0.001). Patients with E showed a significantly higher bolus dispersion than patients with FE (724 +/- 122 cm3 vs. 546 +/- 80 cm3; p < 0.001). However, in patients with FE, bolus dispersion was still significantly higher than in previously published control groups of healthy subjects (546 +/- 80 cm3 vs. 455 +/- 68 cm3; p < 0.001). The results of this study confirm that ADAM and ABD are powerful tools for identifying emphysema even in patients with superimposed pulmonary fibrosis.

Aerosols↗
PubMed1999

Increased fine particle deposition in women with asymptomatic nonspecific airway hyperresponsiveness.

Previous studies suggest that lung function tests using monodisperse aerosols can help to identify early stages of lung diseases. We investigated intrapulmonary particle loss and aerosol bolus dispersion-a marker of convective gas transport-in 32 women with asymptomatic nonspecific bronchial hyperresponsiveness (BHR) compared with 60 women without BHR. Deposition of inhaled particles (0.9 micrometer mass median aerodynamic diameter [MMAD]) was calculated from particle losses of inhaled aerosol boluses consisting of di-2-ethylhexyl sebacate droplets. Convective gas mixing was assessed by the aerosol bolus dispersion method. Women with BHR, nonsmokers as well as smokers, showed significantly increased deposition of aerosol particles (nonsmokers: 45.6 +/- 8.8%; smokers: 49.2 +/- 5.4%; mean +/- SD) compared with the control group of female nonsmokers without BHR (38.2 +/- 9.1%; mean +/- SD) (p < 0.01). Aerosol bolus dispersion values showed a trend for higher values in subjects with BHR (nonsmokers: 572 +/- 122 cm3; smokers: 587 +/- 85 cm3) compared with the control group (542 +/- 88 cm3) (p = 0.2). Also, the maximal expiratory flow at 25% vital capacity (MEF25) showed a trend for decreased values in nonsmokers with BHR compared with nonsmokers without BHR (64 +/- 16% of predicted versus 78 +/- 24% of predicted; p = 0.03). These results suggest that deposition of inhaled particles (0.9 micrometer MMAD) administered by the aerosol bolus technique is a sensitive index of peripheral lung injury that is usually not assessable by conventional methods.

Adult↗
PubMed1999

Noninvasive diagnosis of emphysema. Aerosol morphometry and aerosol bolus dispersion in comparison to HRCT.

Aerosol-derived airway morphometry (ADAM) and aerosol bolus dispersion (ABD) test are altered in patients with emphysema. We examined the diagnostic power of these aerosol methods in comparison with the noninvasive "gold-standard" HRCT in 50 consecutive patients with various lung diseases. The severity of airflow limitation was mild to moderate in the group of patients without emphysema and moderate to severe in the group of patients with HRCT-confirmed emphysema (FEV(1), 78 +/- 23% pred versus 53 +/- 33% pred; p < 0. 001). Among all lung function parameters under consideration ADAM showed the highest sensitivity and specificity for separating patients with emphysema from those without emphysema (area under the operating characteristics curve: p(ROC), 0.92), followed by ABD (p(ROC), 0.90), a marker for ventilation inhomogeneities. In patients with HRCT-confirmed macroscopic emphysema, peripheral air-space dimensions (EAD) at a relative volumetric lung depth V(pr) of 0.20 measured by ADAM were 155% larger, and bolus dispersion (ABD) at a lung depth of V(p) 600 ml was 53% larger than those observed in patients with other lung diseases (EAD = 0.84 +/- 0.53 mm versus 0.33 +/- 0.10 mm, p < 0.0001; ABD = 706 +/- 154 cm(3) versus 462 +/- 109 cm(3); p < 0.0001). EAD showed a significant correlation with the HRCT visual score (r = 0.78, p = 0.01). ABD showed weak significant correlations with all HRCT parameters under consideration (visual score, pixel density, mean lung density) (r = 0.45 to 0.66; p < 0.05). ADAM and ABD are powerful tools for the noninvasive diagnosis of macroscopic emphysema.

Aerosols↗
PubMed1999

Aerosol-derived airway morphometry and aerosol bolus dispersion in patients with lung fibrosis and lung emphysema.

OBJECTIVE: Patients with lung emphysema show increased aerosol-derived dimensions of peripheral airspaces and increased aerosol bolus dispersion (AD). To apply these tests in epidemiologic studies, the objective of this pilot study was to investigate whether morphometric changes caused by lung fibrosis can be distinguished from those caused by emphysema. DESIGN: This study was designed as a cross-sectional study in which airspace dimensions and AD in patients with emphysema and in patients with fibrosis were compared. Forty patients participated in the study: 20 patients had high-resolution CT (HRCT)-proved lung emphysema and 20 patients had HRCT-proved lung fibrosis. All patients underwent conventional lung function tests, aerosol-derived airway morphometry (ADAM), and AD measurements. RESULTS: Patients with lung emphysema showed normal dimensions of small airways but enlarged airspace dimensions in the lung periphery. Patients with fibrosis showed in all lung depths increased airspace dimensions. AD was increased in patients with emphysema but was normal in patients with fibrosis. CONCLUSIONS: These results show that when using ADAM and AD, morphometric changes caused by emphysema can be distinguished from those caused by fibrosis with high sensitivity and specificity.

Adult↗
PubMed1999

[Diagnostic pneumology using model aerosols].

Clearance of Aerosol Particles from the Airways: Measurement of the efficiency and kinetics of particle clearance from the airways is dependent on the site of particle deposition within the lungs. Insoluble particles deposited in the alveolar region are mainly cleared by macrophages over a period of hundreds of days, whereas particles from the tracheobronchial airways are mainly cleared within hours or days by mucociliary clearance. We introduce a method for mucociliary clearance measurements called 'Radio-Bolus-Scintigraphy'. A small volume of radiolabelled aerosol particles sandwiched in clean air (aerosol bolus) is inhaled near the end of a tidal breath which leads to a preferential deposition of the particles in the airways. Particles were Fe3O4 labelled with 99mTc with an aerodynamic particle diameter of 3.5 microns (monodisperse). The retention of the particles within the lungs was detected by Gamma Camera and Human Scintillation Counter. 26 healthy subjects volunteered in this study (14 nonsmokers and 12 smokers). The half width of the mucociliary clearance was found to be 2.4 h in nonsmokers and 3.3 h in smokers (p < 0.05). Intersubject variability was small, 24 hours after inhalation 55% (+/- 6%) of the inhaled particles were still found in the airways of the subjects. No difference was found between nonsmokers and smokers. Good intersubject reproducibility makes this method useful in therapy control as well as in early diagnosis of changes in mucociliary clearance kinetics and efficiency.

Aerosols↗
PubMed1998

Diagnosis of emphysema in patients with chronic bronchitis: a new approach.

Aerosol-derived airway morphometry (ADAM) and aerosol bolus dispersion (D) are altered in patients or animal models with lung emphysema. This study was performed to examine the sensitivity and specificity of ADAM and D in the detection of emphysema in vivo compared with conventional lung function parameters. The study comprised patients with chronic obstructive bronchitis (COB) without emphysema (group COB; n=19, age 56+/-8 yrs, forced expiratory volume in one second (FEV1)/vital capacity (VC) 66+/-12% predicted) and patients with chronic bronchitis with high-resolution computed tomography-confirmed emphysema (group COB-E; n=20), age 65+/-7 yrs, FEV1/VC 44+/-16% pred). Using monodisperse aerosol particles ADAM assessed the calibres of peripheral airspaces, while D measured convective gas mixing. Among all lung function parameters, ADAM and D showed the highest sensitivity and specificity for separating patients with COB from those with COB-E (area under the receiver operating characteristics curve (pROC) 0.99 and 1.0, respectively). In patients with COB aerosol parameters did not differ from those found in the control group, whereas patients with COB-E exhibited a two-fold increase in peripheral airspace dimensions compared with subjects with COB (0.86+/-0.07 versus 0.37+/-0.02 mm, p=0.0001) and an increase in D by >50% (541+/-74 versus 345+/-42 cm3, p=0.0001). In conclusion, aerosol-derived airway morphometry and aerosol bolus dispersion are powerful tools in the differential diagnosis of chronic obstructive pulmonary disease.

Administration, Inhalation↗
PubMed1997

Detection of impaired intrapulmonary convective mixing by aerosol bolus dispersion in patients with emphysema.

The broadening of an inhaled aerosol bolus (aerosol bolus dispersion) during respiration provides a noninvasive, nonradioactive, and easy to perform technique which is a measure of the extent of convective gas mixing processes in the lung and symmetry of ventilation during the breathing cycle. In this study, this technique was evaluated for the ability to detect ventilation inhomogeneities in pulmonary emphysema (PE). An aerosol bolus undergoes changes in shape between its inspiration and expiration. In comparison with the inhaled bolus, the exhaled bolus is more spread because of convective mixing and may have a shift in the location of the mode caused by asymmetries of filling and emptying of lung units. We hypothesized that in PE these changes differ from healthy subjects and are related to lung health. Twenty nine patients with PE inhaled 25 ml boluses containing 0.9 micron monodisperse aerosol particles into volumetric lung depths of 200, 400, 600, and 800 cm3. The control group were 79 healthy subjects. As each bolus was expired, we measured bolus dispersion (volumetric width at one-half aerosol concentration peak height) and mode shift. In patients with PE exhaled boluses were significantly broader than those exhaled by normal subjects at all volumetric lung depths. At a lung depth of 800 cm3, patients showed a bolus dispersion that was 52% greater than that of healthy subjects (p < 0.0001) and they exhaled the bolus mode earlier (p < 0.0001). Aerosol bolus parameters were not influenced by anthropometric data. Pulmonary function parameters indicating obstruction showed a weak negative correlation with aerosol bolus parameters (R2 < 0.4). The bolus parameters appeared to be supplemental to conventional lung function tests and significantly indicated marked ventilation asymmetry and altered convective gas transport in pulmonary emphysema. The results support the use of the aerosol bolus dispersion test in assessing peripheral parenchymal lung injury.

Administration, Inhalation↗
PubMed1997

[Atypical morphologic lung manifestations of Pneumocystis carinii infection in AIDS patients].

We report on unusual presentation forms of Pneumocystis carinii infection of the lung in two patients with AIDS. A 36-years-old woman presented a cavitation in the lung middle lobe and bullous changes in the apical portion of the right upper lobe on the chest x-ray. The biopsy of these lesions was not diagnostic and the patient was operated on. The surgical specimen of the removed lung segment showed a cavitary lesion with a border of granulation tissue with giant cells, focal recent and older hemorrhages, rests of fibrinous exudate and dystrophic calcifications. In the surrounding tissue there were Pneumocystis carinii in the alveolar spaces and also in the alveolar walls, this tissue invasion through the organisms being most probably the cause of the cavitary change. A cytomegalic virus infection was also found. A 30-years-old man presented patchy pulmonary infiltrates on his x-ray. The examination of bronchial secretion and bronchial washing specimens revealed P. carinii. In addition, the organisms were demonstrated in the walls of pulmonary vessels and in the stroma of the bronchial mucosa on the biopsy. In a sample of lung tissue which was taken after death, there were no Pneumocystis carinii anymore, but some proliferations of connective tissue with giant cells and calcification, which could represent residual changes of the Pneumocysts carinii infection. Besides, persisting changes of cytomegaly were found. We conclude that a Pneumocystis carinii infection should be considered in all HIV-positive or AIDS patients with any kind of lung lesions.

AIDS-Related Opportunistic Infections↗
PubMed1995

[Percutaneous ultrasound-guided fine needle puncture of parasitic liver cysts: risks and benefits].

AIM: Percutaneous drainage (PD) has been used successfully in the percutaneous drainage of hepatic hydatid cysts in spite of discouragement by some authors from potential complications such as anaphylactic shock or seeding due to spillage. The aim of this meta-analysis was to evaluate the safety and efficacy of this new form of treatment and to develop a rational approach to the management of liver hydatosis by ultrasound guided PD. METHOD: Relevant articles published in English, French and German from 1983 to 1993 were identified through a computer search of data on the clinical manifestations, complications, anthelmintic treatment in combination with PD and on recurrence rate. RESULTS: 104 hydatid cysts treated by US-guided PD were published in literature. In 25% of the cases diagnosis was unsuspected prior to PD. None of these patients developed serious complications. All symptomatic patients were relieved of symptoms. None of the patients needed surgery. The complication rate was 14.4% and mortality was zero. Anthelmintic drug treatment in combination with PD showed no reduction of side effects. No recurrences were reported during follow-up (3-31 months). CONCLUSION: With proper patient monitoring US-guided PD can be recommended as a routine diagnostic and therapeutic tool in liver hydatosis.

Anthelmintics↗
PubMed1987

Biopsy histamine in ulcerative colitis and Crohn's disease.

The histamine content of biopsy specimens obtained from patients with ulcerative colitis (UC), Crohn's disease (CD), or polyps was measured in vitro. This was done using colonic and rectal mucosa taken from affected and healthy tissue. In general, the results demonstrate a significantly higher histamine content in patients with UC. This was true with respect to colonic as well as rectal mucosa. Moreover, affected mucosa contained significantly more histamine than normal in UC and in CD. The histamine content of colonic and rectal mucosa was similar within each patient group. However, specimens from patients with UC again contained significantly more histamine than did those of patients with CD. The data underscore a distinct pathomechanism in UC and in CD. Therefore, determination of the histamine content of biopsy specimens may be an adjuvant criterion for the discrimination of different inflammatory bowel diseases.

Adult↗
PubMedDate not supplied

Human alveolar long-term clearance of ferromagnetic iron oxide microparticles in healthy and diseased subjects.

Monodisperse ferrimagnetic microparticles (Fe3O4) with 1.3 microm geometric diameter were inhaled to study alveolar long-term clearance in healthy and diseased human subjects. Nineteen younger (age 20 to 39 years) and 20 older (age 40 to 65 years) healthy volunteers participated in the study as well as 15 patients with sarcoidosis (SAR), 12 patients with idiopathic pulmonary fibrosis (IPF), and 15 patients with chronic obstructive bronchitis (COB). In each group the subjects were divided into never smokers (NS) and active smokers (S). Clearance was measured by magnetopneumography (MPG) for 300 days after inhalation. In COB, 50% of the deposited particles were removed from the lungs after 2 days, indicating high bronchial deposits due to bronchial obstructions. In healthy NS, only 10% of the particles were removed after 2 days and cigarette smoking enhanced the fraction of fast-cleared particles. In subjects who smoked, slow clearance was significantly impaired (P < . 02). Clearance half-lives (in days) for younger, healthy, NS were 124 +/- 66 (mean +/- SD) compared to 220 +/- 74 for S. Similarly for older subjects, the timeswere 162 +/- 120 for NS and 459 +/- 334 for S. The impairment of alveolar clearance due to cigarette smoking increases by 5.7 +/- 1.3 days/pack-year (P < .01). Alveolar clearance was impaired in SAR and in IPF; half-lives were 275 +/- 109 days (P < .05) and 756 +/- 345 days (P < .02), respectively, compared to healthy NS. Most COB patients were ex-smokers, their long-term clearance was 240 +/- 74 days, which is more than healthy NS (P < .01), but less than healthy S and might indicate a recovery of alveolar clearance. In view of studies using totally inert particles like Teflon, we conclude that the lung clearance measured with iron oxide tracer particles primarily reflects clearance by intraphagosomal particle dissolution within alveolar macrophages, which is impaired by cigarette smoke consumption and in patients.

Administration, Inhalation↗