Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ASPIRATION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 901 records · Page 50Linked to original sources

Ultrasound-guided fine needle aspiration biopsy of portal vein thrombosis in liver cirrhosis: results in 15 patients.

Between 1988 and 1992 ultrasound-guided fine needle aspiration biopsies of thromboses in the main branches of the portal vein were carried out in 15 patients with liver cirrhosis. The aims of the study were to evaluate the usefulness, feasibility and diagnostic accuracy of this procedure in cirrhotics with known or suspected hepatocellular carcinoma. The procedure was carried out only in patients with a platelet count > or = 40,000/microL and prothrombin activity > or = 40%. A single pass, with a 22 gauge spinal needle, was performed in the portal vein lumen. Diagnosis of the aetiology of the portal vein thrombosis was obtained in all 15 cases. In 12 cases, a cytological diagnosis of hepatocellular carcinoma was made. In one case, the neoplastic cells aspirated were compatible with adenocarcinoma, and a subsequent colonoscopy confirmed the presence of colonic cancer. The material aspirated was compatible with chemically-induced thrombosis in one patient who had undergone several percutaneous ethanol injection sessions for treatment of hepatocellular carcinoma, and in the last case only blood was aspirated, thus ruling out the coexistence of hepatic cancer. We conclude that fine needle aspiration biopsy of portal vein thrombosis is a feasible, low risk procedure that facilitates the diagnosis of hepatocellular carcinoma when fine needle biopsy of focal liver lesions fails. Fine needle aspiration biopsy of portal vein thrombosis is also useful in excluding neoplastic aetiology of portal vein thrombosis.

Adenocarcinoma↗

Fine needle aspiration biopsy of tuberculous cervical lymphadenopathy.

Fine needle aspiration biopsies of 42 histologically confirmed tuberculous cervical lesions were studied. Thirty-four patients had subsequent excision of cervical lymph nodes and eight had incision and drainage of cervical abscesses. All aspirates except two (which were inadequate) were satisfactory for diagnosis and contained inflammatory cells. Twenty-seven smears revealed cells typical of granulomatous lymphadenopathy, that is, epithelioid and multinucleated giant cells. Of all aspirates, 17 smears had bacteriological staining by Ziehl-Nielsen technique, nine of which (53%) were positive for acid-fast bacilli. An aspiration biopsy diagnosis of granulomatous or tuberculous cervical lymphadenopathy was made in 30 patients (71%). In regions where mycobacterial infection is common, the presence of granulomatous changes in lymph node aspirates is highly suggestive of tuberculosis. When the aspirates contain purulent material or when tuberculosis is suspected, staining and culture for mycobacteria should be performed. FNA biopsy is a sensitive, specific and cost-effective way to diagnose tuberculous cervical lymphadenopathy and is recommended.

Adolescent↗

Gastric aspirate analysis in the newborn.

The value of gastric aspirate analysis in screening for perinatal infection is disputed. We have studied the cellularity and bacterial content of 231 aspirates from 105 normal, infected and asphyxiated infants, with the following conclusions: (1) A positive culture has no pathological significance. (2). Aspirate cellularity does not correlate with bacterial culture results. (3) An excess of polymorphonuclear leucocytes (PMNL) in aspirates collected at birth is a pathological but non-specific stress response. (4) After birth there is a physiological rise and fall in the aspirate PMNL content parallel to that in the peripheral blood. Aspirate cellularity and bacterial culture are therefore of limited value in the diagnosis of neonatal pneumonia.

Asphyxia Neonatorum↗

Development of a teaching laboratory aid for instruction of fine needle aspiration biopsy cytology technique.

Specialized training is required to obtain adequate cytology smears by needle aspiration biopsy. An educational method that would provide opportunity for numerous trainees to acquire needle aspiration biopsy and cytodiagnostic skills, and which would not result in the interruption of teaching hospital patient care nor result in the use or sacrifice of animals from laboratory animal resources was sought. An aspiration biopsy cytology teaching aid was developed by placing portions of fresh organ tissue from routine submissions to the necropsy laboratory into a specimen container partially filled with chilled normal saline solution. Specimens were stored immersed in saline at 4 degrees C for up to 48 hours. Prior to the cytopathology teaching laboratory period, the specimen container was removed from storage and covered with a latex diaphragm. Instructors responsible for teaching cytodiagnostic techniques used this ex vivo aspiration biopsy cytology device for instruction of fine needle aspiration biopsy, specimen processing, and microscopy. In the teaching laboratory, puncture of the diaphragm and aspiration of a tissue sample with hypodermic needle and syringe was instructed to, and practiced by, numerous trainees simultaneously using clinical operative technique without the need for live animals. Trainees prepared and stained cytology smears as well as evaluated and interpreted specimens in a single, realistic exercise. Such training experience may improve ability of trainees to procure diagnostic-quality biopsy specimens for cytodiagnosis of lesions from clinic patients.

Journal Article↗

An axisymmetric boundary integral model for incompressible linear viscoelasticity: application to the micropipette aspiration contact problem.

The micropipette aspiration test has been used extensively in recent years as a means of quantifying cellular mechanics and molecular interactions at the microscopic scale. However, previous studies have generally modeled the cell as an infinite half-space in order to develop an analytical solution for a viscoelastic solid cell. In this study, an axisymmetric boundary integral formulation of the governing equations of incompressible linear viscoelasticity is presented and used to simulate the micropipette aspiration contact problem. The cell is idealized as a homogeneous and isotropic continuum with constitutive equation given by three-parameter (E, tau 1, tau 2) standard linear viscoelasticity. The formulation is used to develop a computational model via a "correspondence principle" in which the solution is written as the sum of a homogeneous (elastic) part and a nonhomogeneous part, which depends only on past values of the solution. Via a time-marching scheme, the solution of the viscoelastic problem is obtained by employing an elastic boundary element method with modified boundary conditions. The accuracy and convergence of the time-marching scheme are verified using an analytical solution. An incremental reformulation of the scheme is presented to facilitate the simulation of micropipette aspiration, a nonlinear contact problem. In contrast to the halfspace model (Sato et al., 1990), this computational model accounts for nonlinearities in the cell response that result from a consideration of geometric factors including the finite cell dimension (radius R), curvature of the cell boundary, evolution of the cell-micropipette contact region, and curvature of the edges of the micropipette (inner radius a, edge curvature radius epsilon). Using 60 quadratic boundary elements, a micropipette aspiration creep test with ramp time t* = 0.1 s and ramp pressure p*/E = 0.8 is simulated for the cases a/R = 0.3, 0.4, 0.5 using mean parameter values for primary chondrocytes. Comparisons to the half-space model indicate that the computational model predicts an aspiration length that is less stiff during the initial ramp response (t = 0-1 s) but more stiff at equilibrium (t = 200 s). Overall, the ramp and equilibrium predictions of aspiration length by the computational model are fairly insensitive to aspect ratio a/R but can differ from the half-space model by up to 20 percent. This computational approach may be readily extended to account for more complex geometries or inhomogeneities in cellular properties.

Biomechanical Phenomena↗

[Detection of lesions in bone marrow for the diagnosis of miliary tuberculosis: reliability of bone marrow aspiration and biopsy in view of distribution pattern of lesions in autopsy cases].

The usefulness of the serial section method was investigated in four bone marrow aspirates, four biopsies and nine autopsy specimens obtained from patients with miliary tuberculosis who were admitted to our hospital between 1974 and 1994. In original sections, granulomas consistent with tuberculosis were found in two out of four aspirate specimens (50%) but in none of the four bone marrow biopsies. By using serially out sections, however, granulomas were detected in two more aspirate specimens and two biopsies which were negative in original sections. Consequently four of four aspirates (100%) and two of four biopsies ((50%) became positive. In addition, the distribution of granulomas was investigated using vertebral bone marrows obtained from 12 autopsy cases. We divided the vertebral bone marrows obtained from 12 autopsy cases. We divided the vertebra into the peripheral and central portions. Granulomas were more frequently found in the peripheral portions than in the central. The higher detection rate of granulomas in the peripheral bone marrow when the biopsy and aspiration needles easily reach, suggests that bone marrow aspiration and/or biopsy would be a useful procedure for the diagnosis miliary tuberculosis. Therefore if serial sections were utilized for such samples in the miliary tuberculosis patients, the detection rate is expected to became much higher.

Aged↗

Reproducibility of quantitative cultures of endotracheal aspirates from mechanically ventilated patients.

Ventilator-associated pneumonia is frequently diagnosed with quantitative cultures of samples obtained by bronchoscopic techniques, a method associated with high costs and potential adverse effects. Quantitative cultures of endotracheal aspirates are easier and cheaper to obtain, and good correlations between the results of this method and those of bronchoscopic methods have been reported. However, the reproducibility of quantitative cultures of endotracheal aspirates has never been determined. We studied the quantitative analysis of endotracheal aspirates from 21 mechanically ventilated patients taken during two study days with 2- and 6-h intervals between samplings. In all, 40 endotracheal aspirates were obtained. For mechanically ventilated patients, the median variation of quantitative culture results was 12.3% (range, 0 to 63%), corresponding to 0.7 log CFU/ml. Furthermore, variation was independent of the interval of time between samplings. Persistence of significant numbers of pathogens in quantitative cultures (> or = 10(5) CFU/ml) of the consecutive endotracheal aspirates occurred in 82% of samples. We conclude that results of quantitative cultures from endotracheal aspirates are reproducible and may be useful in diagnosing ventilator-associated pneumonia.

Adolescent↗

Diagnosis of metastases from testicular germ cell tumours using fine needle aspiration cytology.

The cytological features of testicular germ cell tumours were established in smears from 15 freshly resected tumours. These features were applied to the fine needle aspiration cytology diagnosis of metastases in 27 patients referred for chemotherapy. There were 16 positive reports in 32 aspirates of which 13 were taken before chemotherapy and three in patients with residual or new masses after chemotherapy. Teratomas and typical seminomas showed certain characteristic morphological features in cytological preparations which when present in fine needle aspiration cytology material enabled tumour types to be diagnosed. Spermatocytic and anaplastic seminoma were not represented in this series. It is unlikely that these could be distinguished from malignant teratoma undifferentiated (MTU) in the fine needle aspiration cytology material. Metastases from carcinomatous areas in MTU and malignant teratoma intermediate (MTI) may not be distinguishable in fine needle aspiration cytology material from metastatic adenocarcinoma or undifferentiated carcinoma from a different primary site. Positive cytological findings are of value to the oncologist in the management of patients with metastases from testicular germ cell tumours; negative cytology does not exclude the presence of viable tumour. The sampling of small foci of viable tumour in large necrotic masses persisting after chemotherapy is a problem for radiologists, cytologists, and histopathologists. This paper does not advocate the use of fine needle aspiration cytology for the diagnosis of primary testicular tumour.

Abdominal Neoplasms↗

Wide needle aspiration cytology in the diagnosis of lymphadenopathy in Zambia.

AIMS: To study the value of wide needle (19 gauge) aspiration cytology in the diagnosis of lymph node disease in Zambia in the absence of a trained cytologist. METHODS: Patients (n = 304) referred for surgical biopsy of an enlarged peripheral lymph node were studied prospectively. Surgical biopsy was routinely preceded by 19 gauge needle aspiration of the same node; aspirates were stained by haematoxylin and eosin and Ziehl Neelsen stains. RESULTS: Of 232 aspirates, 182 contained sufficient material for cytological characterisation. Tuberculosis was diagnosed or suspected in 122 of 126 aspirates with histologically confirmed tuberculous lymphadenitis; reactive follicular hyperplasia in 31 of 38 patients with primary HIV lymphadenopathy; malignancy in all five patients with malignant nodes; and Kaposi's disease in four of nine patients with this. Tuberculous lymphadenitis was falsely suspected in four patients, as was reactive follicular hyperplasia in four, and Kaposi's disease in four. CONCLUSIONS: Wide needle aspiration cytology is useful in the diagnosis of lymphadenopathy in Central Africa, with the exception of lymphadenopathic Kaposi's disease.

Adolescent↗

Immediate assessment of fine needle aspiration cytology of lung.

AIMS: To assess the value of immediate assessment of cytology in percutaneous fine needle aspiration (FNA) cytology of lung. METHODS: FNA specimens from 75 consecutive patients with suspected pulmonary neoplasms were subjected to immediate cytology assessment. Direct smears were prepared in the radiology department and stained using the Diff Quik method. The cellular content was assessed and, if possible, a provisional diagnosis offered. A second FNA was requested if the initial aspirate seemed of doubtful adequacy. The diagnostic accuracy was examined by review of clinical and radiological data in all patients, and by correlation with other histological or cytological material in 25 patients. Complications of the procedure were identified during the clinical review. RESULTS: Two of 75 specimens were inadequate for diagnosis. Satisfactory diagnostic material was obtained in 51 patients on a single aspirate and following a second FNA in 22 patients. Of the 73 satisfactory aspirates, 58 were malignant, one highly suspicious of malignancy and 14 reported as negative for malignancy. All malignant diagnoses were confirmed on clinical or pathological review. FNA accurately distinguished primary small cell and large cell carcinomas in those patients with pathological follow up. There were two false negative reports, one due to sampling error and the other due to misinterpretation of aspirate material. The diagnostic specificity was 100% and sensitivity 96.6%. Complications were recorded in seven (9.3%) patients, five of whom developed pneumothorax; a chest drain was required in one patient. CONCLUSIONS: Percutaneous FNA cytology provides safe and accurate diagnosis in the investigation of pulmonary lesions. Immediate cytology assessment ensures that aspirate material is handled optimally, and those patients requiring further sampling or ancillary investigation identified rapidly. The number of unsatisfactory and false negative lung FNA are therefore reduced. The complication rate is minimised by decreasing the number of pleural punctures.

Adult↗

Fluorescence in situ hybridisation detection of erbB2 amplification in breast cancer fine needle aspirates.

AIM: To develop a method for the detection of amplification of the erbB2 oncogene in breast cancer fine needle aspirates using fluorescence in situ hybridisation (FISH) and to compare amplification with immunohistochemical detection of the erbB2 protein. METHODS: A digoxigenin labelled probe to the erbB2 gene was hybridised to 15 aspirates prepared from operative breast cancer specimens. A chromosome 17 centromere probe was also hybridised to the aspirates either separately or in combination with the erbB2 probe. The aspirates were scored for erbB2 amplification and chromosome 17 centromere number. Subsequently, paraffin wax embedded sections of the tumours were stained with the antibody CB11 and scored for the presence of membrane staining. RESULTS: Three of the 15 tumour aspirates showed high level amplification of erbB2 detected by FISH. These three tumours also showed chromosome 17 polysomy and diffuse membrane staining by immunohistochemistry. CONCLUSIONS: FISH can be used to detect erbB2 amplification in fine needle aspirates and results correlate with conventional immunohistochemical staining. Difficulties were encountered in the visualisation of the signals in non-amplified cases without the use of specialised digital imaging.

Biopsy, Needle↗

Transbronchial fine needle aspiration.

In a pilot study, 21 patients underwent transbronchial fine needle aspiration (TBFNA) using a 45 cm-22 gauge needle guided by means of a semi-rigid metal sleeve, which was introduced through a standard rigid bronchoscope. A total of 33 aspirations were performed from main carina (15), paratracheal (five), and lobar carinal (13) foci. Six aspirations yielded malignant cellular samples, 22 aspirations presented only normal cells, and in five no adequate cellular sample was obtained. Fifteen patients underwent surgical exploration (mediastinoscopy with or without thoracotomy). Four of the cytologically malignant cases were explored and in three the aspiration site was confirmed histologically. In the remaining patients where the site of aspiration was explored, no tumour was demonstrated in the cytologically negative or cytologically inadequate cases. There were no complications from TBFNA. We suggest that TBFNA is useful in determining mediastinal malignant involvement rapidly and with lesser invasion than with current techniques.

Biopsy, Needle↗

US-assisted aspiration thrombectomy: in vitro investigations.

The authors describe the use of a new ultrasound (US)-aspiration thrombectomy technique. An oscillating US probe was inserted into a thin-walled, large-bore aspiration catheter. Experiments tested the ability of the new device and other catheter combinations to remove clot material from a Petri dish, as well as from small and large vessel models made of silicone and glass tubes, respectively. Results of the experiments demonstrated that an oscillating 1.0-mm US probe inserted into an aspiration catheter (7-9 F in diameter) promoted clot fragmentation and allowed continuous aspiration of thrombi of any size. When compared with simple large-bore catheter aspiration and with mechanical fragmentation by means of a US probe within a catheter that was flushed to cool the probe, US-assisted aspiration thrombectomy demonstrated significantly better results for percutaneous transcatheter removal of fresh thrombi.

Equipment Design↗

Hip aspiration: a cost-effective and accurate method of evaluating the potentially infected hip prosthesis.

PURPOSE: The accuracy of fluoroscopy-guided hip aspiration in the diagnosis of infection in hip prostheses was evaluated. MATERIALS AND METHODS: Results from 147 preoperative aspiration cultures were compared with results of operative cultures. The relative costs of aspiration and nuclear medicine studies were also compared. RESULTS: With the operative culture results as the standard, sensitivity of hip aspiration was 92.8% and specificity was 91.7%. The negative and positive predictive values were 99.2% and 54.2%, respectively. Aspiration arthrography costs approximately 20% as much as complementary technetium sulfur colloid-indium-111 granulocyte scans, the most accurate nuclear medicine study used to evaluate potentially infected hip prostheses. CONCLUSION: Hip aspiration is an accurate and cost-effective method of evaluating the potentially infected hip prosthesis.

Bacteria↗

Aspiration of a large pneumothorax resulting from transthoracic needle biopsy.

PURPOSE: To determine whether simple aspiration of air from the pleural space could obviate chest tube placement in patients with a large pneumothorax after transthoracic needle biopsy. MATERIALS AND METHODS: Seventeen patients, who developed a large pneumothorax (> 30%) during computed tomographic (CT)-guided transthoracic needle biopsy and otherwise would have required chest tube placement, underwent percutaneous aspiration of the pneumothorax while on the CT scanner table. Air was aspirated from the pleural space by using an 18-gauge intravenous catheter attached to a three-way stopcock and a 50-mL syringe. The patients were positioned with the puncture site down after aspiration of the pneumothoraces and oxygen was administered both during and after the procedure. RESULTS: The pneumothorax was almost completely aspirated in all 17 patients. Twelve (70%) patients did not require chest tube placement. Follow-up chest radiographs obtained 2 and 4 hours after the procedure revealed complete or almost complete resolution of the pneumothorax in eight (47%) patients and partial recurrence of a small, stable pneumothorax in four (24%) patients. The remaining five (29%) patients had recurrence of their pneumothorax, which ultimately required chest tube placement. CONCLUSION: Percutaneous catheter aspiration of a large biopsy-induced pneumothorax is safe and easy to perform and may obviate chest tube placement.

Adult↗

Neutrophil accumulations due to pulmonary thromboxane synthesis mediate acid aspiration injury.

Acid aspiration leads to lung injury associated with high levels of plasma thromboxane (Tx). This study tests the role of Tx synthesis by the aspirated lung segment in mediating local and remote neutrophil (PMN) sequestration, alveolar diapedesis, and permeability edema. Anesthetized rats underwent tracheostomy and insertion of a fine-bore cannula into the anterior segment of the left lung. This was followed by the installation of either 0.1 ml saline (n = 18) or the Tx synthase inhibitor OKY 046 (0.1 mg/kg in 0.1 ml, n = 18). Twenty minutes later either 0.1 ml 0.1 N HCL or 0.1 ml saline was similarly introduced (n = 18). Three hours later, in the saline-HCl group, the rise in Tx concentration in both plasma (1,340 pg/ml) and bronchoalveolar lavage (BAL) fluid (2,100 pg/ml) was higher than that in the saline-saline aspirated control group (350 and 115 pg/ml, respectively; both P less than 0.05). In the acid-aspirated lung PMN sequestration [87 PMN/10 high-power fields (HPF)] and diapedesis (96 x 10(4) PMN/ml in BAL) were higher than control values of 7 PMN/10 HPF and 3 x 10(4) PMN/ml (both P less than 0.05). Acid aspiration induced local permeability edema with a high protein concentration in BAL of 3,350 micrograms/ml and an increase in lung wet-to-dry weight ratio (W/D) of 6.6, both higher than control values of 482 micrograms/ml and 3.4, respectively (P less than 0.05). Leukosequestration in the aspirated side started at 30 min and was progressive over a 3-h monitoring period.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Pharyngoglottal closure reflex: characterization in healthy young, elderly and dysphagic patients with predeglutitive aspiration.

BACKGROUND: Mechanism(s) of aspiration, a common complication of oropharyngeal dysphagia, is not completely elucidated. Since the pharyngoglottal closure reflex induces vocal cord adduction in healthy young humans, it may help prevent aspiration during premature spill of oral content. OBJECTIVE: The objective of this study was to characterize this reflex in normal young and elderly humans and dysphagic patients with predeglutitive aspiration; a potential group for developing abnormalities of this reflex. METHODS: We used a concurrent video endoscopic and manometric technique for recording of the vocal cords' response to pharyngeal water stimulation. We first studied 9 young (26 +/- 2 years) and 9 elderly (77 +/- 14 years) healthy volunteers to characterize and determine the effect of aging on the pharyngoglottal closure reflex. Subsequently, we studied 8 patients (65 +/- 16 years) with predeglutitive aspiration and 7 age-matched controls to characterize this reflex among patients with compromised airway safety during swallowing. RESULTS: The threshold volume of water for triggering both glottal closure and reflexive pharyngeal swallow in the elderly volunteers for rapid pulse injection was significantly larger than that for the young (p < 0.05). Neither glottal closure reflex nor pharyngeal reflexive swallow could be induced in any of the dysphagic patients with volumes of injected water as large as 1 ml. In contrast, in all age-matched controls, both the pharyngoglottal reflex and reflexive pharyngeal swallow were stimulated with threshold volumes of 0.3 +/- 0.07 and 0.6 +/- 0.05 ml, respectively. CONCLUSIONS: Pharyngeal stimulation by water induces vocal cord adduction in humans; the pharyngoglottal closure reflex. Although preserved, a significantly larger volume of water is required to stimulate this reflex by rapid pulse injection in the elderly, suggesting some deterioration in this age group. The pharyngoglottal closure reflex induced by rapid pulse injection is absent in dysphagic patients with predeglutitive aspiration, suggesting its contribution to airway protection against aspiration.

Adult↗

Computed tomography controlled aspiration surgery for hypertensive intracerebral hemorrhage. Experience of more than 400 cases.

To overcome the disadvantages of conventional surgery, we developed our own method of computed tomography controlled stereotactic aspiration surgery for hypertensive intracerebral hemorrhage. A new ultrasonic surgical aspirator was also developed to facilitate aspiration of a dense clot in the acute stage. Between 1980 and 1988, 437 patients with hypertensive intracerebral hemorrhage underwent aspiration surgery. Computed tomography controlled stereotactic aspiration surgery can be performed in hematomas of any site or any stage with minimal tissue damage, even in aged patients. Aspiration surgery led to a favorable clinical experience and outcome, especially in the acute stage.

Activities of Daily Living↗