Study on erythrocyte aggregation using computerized image analysis methods.

AIM: To study the relationship between erythrocyte aggregation and physical parameters: temperature and pH. MATERIAL AND METHODS: Aggregation was evaluated using computerized image analysis by Aggregate Shape Parameter (ASP), defined as the ratio of the aggregate projected area to its square perimeter, and erythrocyte aggregation index (EAI). EAI was measured and compared at different temperatures (4 degreeC, 20 degreeC, 37 degreeC) and different pH values (3, 5, 7 and 9). RESULTS AND DISCUSSION: The results show that the increase in temperature induces EAI increase and a decrease in Ph, a decrease of erythrocyte aggregation. It was found that, at pH=3 and 5, erythrocytes are destroyed and, at pH=9 RBC clusters are formed. CONCLUSIONS: RBC aggregate shape reflects intercellular interaction and its quantification may thus be another characteristic of RBC aggregation. Increased RBC aggregation was observed in various pathological states, such as diabetes and myocardial infarction, or following trauma.

[Assessment of some biophysical parameters of human erythrocyte by FT-IR spectroscopy--preliminary study]. / Evaluarea unor parametri biofizici ai eritrocitului uman prin spectroscopie FT-IR--studiu preliminar.

UNLABELLED: Based on the biochemical composition of erythrocyte membrane and asymmetric distribution of phospholipids, proteins, and cholesterol, FT-IR spectroscopy can monitor the distribution and interaction pattern of membrane constituents. MATERIAL AND METHODS: The study series included 21 clinically healthy subjects aged between 20 and 60 years. Complete blood counts were performed and the serum biochemical compounds (cholesterol, triglycerides, total protein, glucose) were determined. RESULTS AND DISCUSSIONS: The parameters that can be assessed by erythrocyte FT-IR in relation with the biochemical factors that may influence membrane fluidity are: degree of fatty acids unsaturation, saturated fatty acids/unsaturated fatty acids ratio, cholesterol/phospholipids ratio, and phospholipids/protein ratio. Based on the obtained results, in the assessment of membrane status the following vibration modes were selected as spectral parameters: vibration associated valence bond (=CH), asymmetric valence CH2 groups, modes associated with P=O bond and amine bands I and II specific for proteins. Other parameters, such as v(C-O) specific to glucose, may provide additional information on glucose metabolic status. CONCLUSIONS: By correlating biochemical markers with these spectral parameters information on red cell membrane status, status that may reflect different pathological processes, can be obtained.

[Membrane fluidity--biophysical parameter in relation to membrane transport processes]. / Fluiditatea membranara--parametru biofizic in relatie cu procesele de transport membranare.

Membrane fluidity is a complex parameter, influenced both through some biophysical (temperature, electrical charges, pH) and biochemical factors (protein/phospholipids ratio, phospholipids/cholesterol ratio, degree of fatty acids unsaturation). It is a parameter that reflects the main membrane characteristic organization (gel or liquid crystal structure). Experiments provide consistent data about membrane fluidity relations to various cellular processes, especially membrane processes. Passive transport is influenced directly by membrane lipid composition, and consequently, membrane fluidity, or by channels and carriers molecules interactions with adjacent membrane lipids. Membrane diffusion is related both to the hydrophobic nature of the particles and of the membrane environment. Depending on the mode of interaction with membrane proteins, lipids may be classified as non-annular lipids, annular and "mass" lipids. Different types of fatty acids affect the function of many channels, by stimulating or inhibiting them. These effects might be mediated through direct binding of the lipids to the channel or through indirect hydrophobic interactions. Active transport pumps conformation could be modulated, also, through interactions with adjacent lipids of the bilayer (especially cholesterol) and membrane micro-domains organization. In conclusion, membrane fluidity is close related both to passive and active transport.

[Unique monoblock lung right-left, unique pleural cavity]. / Plamân monobloc dreapta-stânga. Cavitate pleurala unica. Plamîn hipoplazic stâng. Caz clinic.

A 34-year-old female with WPW syndrome has been under surgical treatment in our clinic with left basal chronic pleural empyema. During the surgical intervention multiple anatomical anomalies were detected, like unique pleural cavity, monoblock lung left-right, hypoplasic left lung, no scissures on the left side, no left pulmonary arteria with an aberrant arteria for the left lung derived from the right pulmonary arteria, the same for the bronchis. The pleural-pulmonary shelling proceeded without incidents and it has been finalized with the drainage of the whole pleural cavity.

[PSA as a marker for prostate cancer progression]. / PSA CA marker in evolutia cancerului de prostata.

Monitoring the evolution of prostate cancer has crucial importance since this tip of neoplasia has a variable biology, ranging from latent cancers to extremely aggressive tumors. At the moment, PSA (prostate specific antigen) values point out to either successful or unsuccessful prostate cancer therapy. Depending on therapeutic strategies, biochemical recurrence (BCR) is differently defined. After radical prostatectomy, the PSA declines to undetectable levels in 3-4 weeks; BCR: PSA = 0.2-0.5 ng/mL for a single measurement or two consecutive values which surpass 0,2-0,4 ng/mL. PSADT < 10 months is a predictor for the progression of the disease. After external beam therapy, PSA is slowly decreasing reaching up the nadir of 0.2-0.5 ng/mL in months or years; BCR: PSA = nadir + 2 ng/mL. In the case of brachytherapy, the nadir is reached in 2-4 years; BCR: nadir + 2 ng/mL. After hormonal therapy, PSA declines in 3-6 months, maintains low values for 18-24 months, then increases, settling for hormone independency. After chemotherapy, PSA is considered normal at values < 2 ng/mL; the response of PSA represents a confirmed decreasing from the second test at 4 or more weeks after the initial decline; the length of the response is the period between first decline with 50 % of PSA to 50 % increase from nadir; the progression of PSA is shown in the increase with 25 % in comparison to the basic level. In the case of active monitoring, a PSADT < 2 years is an indication for radical prostatectomy, but there are cancers which can evoluate despite a stable PSA. The "PSA bounce" phenomenon and the "PSA surge postchimiotherapie" syndrome can complicate the assessment of biochemical recurrence.

[Thermal and structural properties of nano- and micro-filled composites]. / Proprietati termice si structurale ale unor compozite dentare cu nano- si micro-filler.

The thermal and structural properties of nano-filled and micro-filled restorative composites (Filtek Supreme XT and Filtek Z250) are studied in comparison with the ones of teeth. Our results show slightly decreased values of the thermal constants of Filtek Supreme XT with respect of Filtek Z250. Both analyzed composite materials have the values of the thermal conductivity and diffusivity very close to the one of enamel, with the better fitting in the case of Filtek Supreme XT. Comparing the effusivities, a good compatibility with all dental tissues resulted. The thermal expansion coefficient is about two times higher for Filtek Supreme XT than Filtek Z250 which fits better with the one of teeth. The chemical composition is similar for both composites except for zirconium which indicate a lower percent of zirconia particle for Filtek Supreme XT.

[Studying erythrocyte deformation by optical methods]. / Studiul deformabilitatii eritrocitare prin metode optice.

UNLABELLED: Erythrocyte deformation is an important factor of the microcirculation in physiological and pathophysiological conditions. MATERIAL AND METHOD: Deformability was evaluated through the elongation index (IE) using two instruments based on optical methods: LORCA and RHEODYN-SSD. RESULTS: The elongation index (IE) was compared for normal red blood cell (RBC) and heated RBC at 49 degrees C for 9, 30, 60 minutes duration. Erythrocyte deformability was measured for RBC treated with diamide (two concentrations), too. The results show that the increase of the diamide concentration induces the increase of the rigidity and a decreased deformability through the decreased IE. The elongation index was found decreasing as long as the time of heating is bigger, the RBC becoming more rigid.

[Parathyroid glands involvement in multiple endocrine neoplasia]. / Interesarea paratiroidelor in neoplaziile endocrine multiple.

UNLABELLED: Multiple endocrine neoplasias are syndromes characterized by the involvement of at least two endocrine glands. Parathyroid gland involvement is usually noted in Multiple Endocrine Neoplasia (MEN) type I and type II. Parathyroid glands tumor associated with endocrine pancreatic tumor, as well as pituitary tumors is the typical pattern of MEN I. The parathyroid gland is the most frequent abnormality in MEN I. CASES REPORTS: We presented five cases with MEN I and parathyroid glands involvement. In three cases with young ages (28-33 years old) and familial setting, the MEN I syndrome was "complete" (parathyroid adenoma, gastrinoma or insulinoma and pituitary adenoma--prolactinoma or GH-secreting tumors), and, in the other two cases, with 57 and 68 years old respectively, the MEN I syndrome was "incomplete" with parathyroid glands and pituitary gland involvement. The cases with gastrinomas were operated in emergency for complication of peptic ulcer (perforation associated with peritonitis and gastro-intestinal bleeding); then the pancreatic tumors were diagnosed and left pancreatectomy with spleen preservation and respectively, tumor resection have been performed. Hyperparathyrodism was then diagnosed and subtotal parathyroidectomy has been performed in both cases. Unfortunately one patients died due to severe endocrine disorder. During the necropsy, the pituitary adenoma has been diagnosed. The third case with "complete" MEN was a women of 33 years old, admitted for severe hypoglycemia. The imagistic and laboratory test diagnosed a tumor situated into the pancreatic body, and an parathyroid adenoma. The resection of pancreatic tumor associated with resection of the parathyroid adenoma, in the same time, were performed. The other two cases with "incomplete" MEN were older then the first patients, and were diagnosed with hyperparathyrodism and pituitary gland tumor. The resection of parathyroid gland adenoma has been performed in both cases, with uneventful postoperative course. The literature data was also discussed. CONCLUSIONS: The parathyroid glands involvement in MEN is common. There are two kinds of MEN associated with parathyroid gland involvement: the "complete" form, especially in young patients, with diffuse involvement of the parathyroid glands, and the subtotal parathyroidy is the best choice, and the "incomplete" form, especially in elderly, with the involvement of a single parathyroid gland; in this way, the resection of the adenoma associated with biopsy from the other parathyroid gland is the best approach. The presence of gastrinomas, complicate the disease prognosis and the surgical approach. The treatment of these patients is challenging and has to be done in multidisciplinary team.

[Animal model of acute respiratory distress syndrome]. / Model animal de SDRA.

UNLABELLED: Studying the animal models of acute respiratory distress syndrome (ARDS) represents a key factor in understanding the pathophysiology of this condition. OBJECTIVE: Creating a simple animal model of ARDS based on oleic acid injection, suitable for studying the alveolo-capillary membrane dysfunction. MATERIAL AND METHOD: 8 common rabbits weighting between 3 and 3.5 kg were subjected to peripheral vein injection of 0.5 ml of oleic acid. During the first 75 minutes chest radiographs were performed at each 15 minutes. At the end of this period an arterial blood-gas analysis was done, the animals were sacrificed and a complete autopsy and a microscopic examination of the lung were performed. RESULTS: Clinical, radiologic and histological features of ARDS were obtained in all cases after 75 minutes of oleic acid injection. CONCLUSION: Intravenous injection of oleic acid consistently induces ARDS in rabbits. The model is simple, reproducible and suitable for animal experimentation.

[Unusual forms of liver abscesses]. / Forme particulare de abces hepatic.

UNLABELLED: Liver abscess is a rare disease. In this paper we present five unusual cases of liver absceses. These cases represents 5.68% from all patients with liver abscesses treated in the First Surgical Clinic Iasi, from 1977 to 2007. The ethiology of the abscesses was different: intrahepatic biliary duct migration of Ascaris lumbricoides, migration of a foreign body (toothpick) from stomach into the liver, infected hydatid cyst with a large biliary leak and cholangitis and, residual cavities after surgical treatment of hepatic hydatid cyst associated with foreign bodies. Another case was a patient with a very large, multilocular liver abscess (2000 mL) with biliary ethiology. In all cases a surgical drainage was performed. In the cases with hydatid cysts and biliary leakage, ERCP procedures were performed. The postoperative course was uneventful. CONCLUSIONS: Surgical treatment remains a valuable option in the treatment of pyogenic hepatic abscesses especially in unusual form.

[Scintigraphic visualization of Pgp protein: a non-invasive method to evaluate the MDR cellular character]. / Vizualizarea prin scintigrafie a proteinei Pgp--metoda neinvaziva de evaluare a caracterului MDR tumoral.

The MDR character is a major factor that influence the effectiveness of cancer chemotherapy. This feature can be noninvasively evaluated through 99mTc isonitrils (MIBI, Tetrofosmin) scintigraphy, because these radiotracers cellular efflux is mediated by the Pgp membranar active transport system, the same that mediate chemotherapy drugs cellular efflux. The Pgp glycoprotein overexpression in the case of the MDR positive tumoral cells will determine both the chemotherapic drug and the isonitrile radiotracer quickly efflux from the cell. This paper present, based both on the literature and personal authors research work, the principle of the method, radiotracers structural characteristics and cellular uptake mechanism, practical protocol details from the acquisition untill the qualitative and quantitative image processing and results interpretation. Quantification indexes are proposed for the radiotracer cellular uptake quantitative evaluation on the scintigraphic image. The results could bring the possibility to make MDR positive patient diagnosis and further selection for the MDR modulators drug therapy.

[German influences on Romanian medical terminology]. / Influente germane asupra terminologiei medicale Românesti.

The medical terminology plays a key part both in the study of medicine as well as in its practice. Moreover, understanding the medical terms is important not only for the doctor but also for the patients who want to learn more about their condition. For these reasons we believe that the study of medical terminology is one of great interest. The aim of our paper was to evaluate the German linguistic and medical influences on the evolution of the Romanian medical terminology. Since the Romanian-German cultural contacts date back to the 12th century we had reasons to believe that the number of German medical words in Romanian would be significant. To our surprise, the Romanian language has very few German words and even less medical terms of German origin. However, when we searched the list of diseases coined after famous medical personalities, we found out that 26 % of them bore the names of German doctors and scientists. Taken together this proves that the German medical school played an important role on the evolution of Romanian medicine despite the fact that the Romanian vocabulary was slightly influenced by the German language. We explain this fact on the structural differences between the Romanian and German languages, which make it hard for German loans to be integrated in the Romanian lexis. In conclusion we state that the German influence on the Romanian medical terminology is weak despite the important contribution of the German medical school to the development of medical education and healthcare in Romania. Key

[The role of fine needle aspiration biopsy in differentiated thyroid carcinoma]. / Utilitatea punctiei cu ac fin in carcinoamele tiroidiene bine diferentiate.

UNLABELLED: Fine needle aspiration biopsy (FNAB) in evaluation of nodular goiter generated a true revolution. It is generally assumed that the use of FNAB reduces the number of surgical procedures by 50%, while doubles the proportion of carcinoma in surgically treated patients. The aim of the study was to demonstrate the utility of FNAB in preoperative diagnosis of thyroid carcinoma. MATERIAL AND METHOD: We have investigated 3240 patients with nodular goiter by FNAB (MGG stain and morphometrical analysis), followed by morphological examination in those who underwent surgery. RESULTS: Globally, FNAB had a good sensitivity (77%) and specificity (95%), which made an accuracy of 92%, proving its diagnostic value. In follicular carcinoma (FC), where the cytological diagnostic cannot be certain, morphometry helped the diagnostic: mean cells diameter was significantly higher (p < 0.001) in FC (9.5 mm) vs. thyroid adenoma (8.6 mm). CONCLUSION: With good statistical value, FNAB remain a useful preoperative diagnostic method.

[Red cell shape--a biophysical analysis]. / Forma eritrocitului--o analiza biofizica.

Red cells have three main characteristics: specific shape--discoidal, deformability and aggregability. To give an explanation for his specific shape there are two ways: a) one, use hypothesis from mechanics, as: interfacial pressure, stress, deformability; b) the other way try to explain it by using data from molecular structure of biomembrane and cytoskeleton who are responsible of specific interactions between molecules. First direction was supported by many models, interesting but unrealized some of them because the theories from macroscopic mechanics wasn't well supported. The second direction, even more interesting then the first, was the subject of many studies but none of them gives a complete explanation for this particular shape of red cells. In present, there are many artificial data obtained experimental or in relation with pathological states. In our opinion, sustained also of literature data, the Helfrich's model is the most truth-like. After 1970, W. Helfrich tries to give an explanation of the particular shape of red cells, based on the curvature of elasticity and the grade of filled with hemoglobin. This model was proved also by experimental data, using "simplified red cells", and has also many others extensions. In the same direction are the studies of T.M. Fischer who describes a shape memory of human red blood cells, sustained experimental.

99mTc isonitrils biophysical aspects in pulmonary tuberculosis. Part II. In vitro evaluation of 99mTc MIBI cellular uptake mechanism.

UNLABELLED: The aim of this experimental work was to assess the uptake of 99mTc MIBI (metoxy-isobutil-isonitril) on Mycobacterium tuberculosis (MT) cultures, and to compare this uptake level with the uptake of two normal cell types in culture (fibroblasts and myocytes), and with MT membrane fluidity. MATERIAL AND METHOD: Mycobacterium tuberculosis cultures were realised on Löwenstein Jensen medium by standard methodology. Normal cells were neonatal rat heart myocytes and fibroblasts. Final plating was done to have an almost complete cell monolayer the day of the experiment, in culture dishes. The cells were incubated with a 1.85 kBq/ml concentration of 9mTc MIBI, at 37 degrees C, using three dishes for each cell type. A three point kinetic (15, 60 and 90 minutes) was realised. Static polarization of fluorescence with Diphenylhexatrien (DPH) fluorescent marker of Mycobacterium tuberculosis in suspension (concentration 10(4)/ml NaCl 9 per thousand) was realized. RESULTS: Mycobacterium tuberculosis have high 99mTc MIBI uptake, 106,47% (compared with the known higher normal uptake cells--the myocytes, considered 100%); the highest uptake kinetic point is at 15 minutes radiotracer incubation. The assessment of Mycobacterium tuberculosis wall fluidity has not brought conclusive results. CONCLUSION: Our results could give informations to understand the Mycobacterium tuberculosis 99mTc MIBI uptake mechanisms in in vivo lesions.

99mTc isonitrils biophysical aspects in pulmonary tuberculosis. Part I. In vivo evaluation of 99mTc MIBI and 99mTc Tetrofosmin biophysical localization mechanisms.

UNLABELLED: The aim of our study was to compare the role of lung perfusion scintigraphy with 1mTc MIBI and 99mTc Tetrofosmin (Mw) for the initial diagnostic evaluation of pulmonary tuberculosis-PTB). MATERIAL AND METHOD: Two groups of new PTB diagnosed patients, without treatment, were studied: group I--41 patients were imaged with 99mTc MIBI (sex ratio men:women = 17:24, mean age 25 years, 26 positive Mycobacterium Tuberculosis (MT) smears, 15 negative MT smears), group II--40 patients were imaged with 99mTc Mw (sex ratio men:women = 21:19; mean age: 32.5 years; 31 positive MT smears, 9 negative MT smears. Both groups received a 7.4 MBq (0.2 mCi)/kg radiotracer i.v. dose. Two anterior planar 3000000 counts/image on the thorax, one at 15 minutes and the other at 60 minutes after radiotracer administration and a SPECT acquisition were performed. For 99mTc Mw, three extra images were, in addition, performed, at 5, 90 and 120 minutes, in order to compare its kinetic with the known 99mTc MIBI kinetic. Clinical, radiological (Rx) and bacteriologic assessments of the patients were also done. RESULTS: Qualitatively, radiotracer uptake classification was coded: without uptake (-); low uptake (+); moderate uptake (++); high uptake (+++). Three identical interest regions were drawn: on the pathologic site, on a homolateral normal pulmonary field and on a myocardial field. The quantification has been assessed using three indexes (counts/pixel): I1= lesion/ normal; I2 = lesion/heart; I3 = normal/heart. We have found a significant difference between the mean value of I1:1.484, in the case of 99mTc MIBI versus 1.95 in the case of 99mTc Mw. The sensibility of the method was 96% for 99mTc MIBI versus 94% for 99mTc Mw, the specificity being 86 % for 99mTc MIBI versus 88% for 99mTc Mw. CONCLUSION: Both radiotracers are useful for the imaging evaluation of PTB, and can give evidence of new sites, related to radiology. The contrast between pathologic and normal uptake is more evident in 99rTc Mw images than in 99mTc MIBI images, how it was demonstrated by the index quantification. The in vivo uptake kinetic for 99mTc Mw seems to be similar with that of 99mTc MIBI for the first 60 minutes but, at 120 minutes showed delayed washout. This can be useful in the differential diagnosis from other lung disease where the radiotracer kinetic is different.

[PET-CT scan: a major progress toward fused, metabolic and functional images]. / PET-CT: un progres major în fuziunea imaginilor metabolice si anatomice.

Positron emission tomography (PET) is an imaging method that allows metabolic mapping of disease processes after a specific radiotracer administration. One of the major disadvantages of using radioactive glucose is the fact that this radiotracer is not entirely specific for tumor tissue. Also, the physiological distribution of 18F FDG makes difficult the anatomical localization. Computed tomography (CT) provides en excellent anatomic resolution but the functional information is reduced. In this circumstances PET and CT gives complementary information, and together increase the lesions localization and reduce the artifacts of interpretation. That was exactly the purpose for building the new hybrid gamma camera PET-CT. The new concept of hardware fusion between PET and CT is now commercially available from five years. By the meaning of fused anatomic and functional imaging PET-CT has already found a number of clinical applications in oncology. The new imaging technology reduces image acquisition time, improves tumor localization which is difficult if not impossible with PET alone, and calculate more accurate the target tumor volume for radiotherapy planning. This article is a review from literature data, concerning the mean indications, weaknesses, current evidence and future directions of PET-CT. In Romania, there are not available either PET or PET-CT. We believe that the aspiration at the European standards will remedy it as soon as possible.

An image pre-processing automatic system for bone scan metastasis evaluation.

Scintigraphic images provide morphologic and functional information referring to pointed human body tissues and organs. Depending on the ability and experience of the nuclear medicine physician and the degree of scintigram complexity, the diagnosis process becomes very difficult sometimes. Image processing might decrease subjectivity and help physicians in decision making in complex cases as bone metastasis diagnosis based on scintigraphic explorations. The aim of this paper is to describe the compulsory steps of a pre-processing method in order to build a database for an automatic final appreciation of pathologic bone scan areas as a percentage of the total bone scintigraphic surface. This may include the scintigraphic result in some metastasis probability category with more accuracy than a simple, subjective appreciation of the scintigram, especially in doubtful cases. This paper points to the steps of the processing method of the database used in the rule-based nuclear medicine aide-decision expert system (NMADES). The objective evaluation of the pathological sites requires image preprocessing operations in a number of steps: histogram transforms, correlated superposition of direct and reversed incidences to reinforce the uptake sites, smoothing by pseudo-cepstrum methods, symmetry axes extraction by robust linear regression and symmetric areas search with fuzzy methods. Some for and against's are underlined in the last section, devoted to conclusions and future work.

Dystonic posturing in seizures of mesial temporal origin: electroclinical and metabolic patterns.

OBJECTIVE: To test the hypothesis that extratemporal neuronal networks are involved in dystonic posturing (DP) observed in mesial temporal epilepsy (MTLE). METHODS: The authors analyzed electroclinical findings in 36 patients with MTLE with or without DP. Three DP types were defined (types I, II, III) corresponding to a gradual increase in duration and complexity. Interictal [18F]fluorodeoxyglucose-PET in different groups and subgroups was compared with control subjects using statistical parametric mapping software (SPM99). RESULTS: DP was found in 20 patients (55%), contralateral to the epileptogenic focus in 95%. Patients with DP had longer seizure duration, higher frequency of head deviation, salivation, motor manifestations, secondary generalization, severe clouding of consciousness, and prolonged postictal confusion when compared with patients without DP. Ictal discharge patterns during DP consisted of fast rhythmic activity spreading to frontal or suprasylvian areas, whereas slow rhythmic activity restricted to the temporal areas occurred in the absence of DP. In patients with DP, widespread temporal and extratemporal hypometabolism including the putamen was found. Hypometabolism was restricted to the anteromesial part of the temporal lobe and anterior insula in patients without DP. Putaminal hypometabolism was found in all DP types, but different extratemporal cortical involvements were found in DP subgroups: insula and inferior frontal gyrus in type I, inferior and superior frontal gyri and anterior cingulate gyrus in type II, and parietal areas in type III. CONCLUSION: Dystonic posturing may result from involvement of both putaminal and extratemporal cortical areas. Moreover, different frontal or parietal networks may be involved according to the duration or complexity of dystonic posturing.

[Radioisotopes for the evaluation of pulmonary capillary permeability in ARDS]. / Evaluarea radioizotopica a permeabilitati capilare pulmonare în ARDS.

The dysfunction of pulmonary capillary represents the marker of Acute Respiratory Distress Syndrome (ARDS). Each current mean of investigation in ARDS (radiography, CT, ultrasonography, double dilution technique, electric impedance, bronchoscopy) has its downfalls and has not succeeded in becoming a gold standard in evaluation of this pathology. The development of any treatment is hampered by the lack of a rapid and objective method of evaluation of the progress of the disease. The radioisotopic evaluation of pulmonary capillary permeability realizes a picture of a physiologic process blood-interstitial exchange at pulmonary level. The most recent studies appear to suggest that this method of investigation can objectively evaluate and be a predictive parameter for ARDS evolution. We will present the principle of the radio-isotopic method and some of its current clinical applications.