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At least 451 records · Page 25Linked to original sources
PubMed1986

A blind controlled trial of phase-contrast microscopy by two observers for evaluating the source of haematuria.

Two observers, unaware of each other's findings and of the diagnosis, examined red cells in the urine of 109 patients by phase-contrast microscopy. All specimens were examined uncentrifuged by inverted microscopy, and 48 of the 109 were also examined under a light microscope after centrifugation. We were unable to confirm with either method the close correlation between red-cell morphology and diagnosis reported in previous studies, and our 2 observers differed in their interpretation on 38% of occasions. Proteinuria associated with the presence of casts in uncentrifuged urine examined by inverted microscopy was a better indication than red-cell morphology of renal parenchymal disease.

Centrifugation↗
PubMed1989

[Microbial populations and periodontal condition--evaluation by differential phase contrast microscopy].

The purpose of this study was to determine correlations between various clinical assessments of inflammatory periodontal disease and the proportion of bacterial morphotypes in the subgingival flora of sites representing widely varying states of periodontal disease. Phase-contrast microscopy was used to determine the proportion of varying bacterial morphotypes at 154 sites. For each site the following clinical assessments were recorded: gingival index, probing depth, plaque index and calculus index. Statistically significant (p less than 0.01) positive correlations were found between gingival index and spirochetes or motile rods, and between probing depth and spirochetes. Significant negative correlations were found between gingival index and coccoid cells, and between probing depth and coccoid cells or rods. The significant increase in the proportion of spirochetes or motile bacteria occurred when bleeding upon probing was observed. The ratio of motile to non-motile cells at advanced disease sites was in the vicinity of 1:1. The data obtain in this study may be useful in monitoring the effects of various treatment modalities on the periodontal flora and may be helpful in determining the presence or absence of active disease.

Bacteria↗
PubMed1998

[Values of phase-contrast microscopy in the etiological diagnosis of hematuria in adults. Part I. Establishing individual norms for glomerular hematuria].

UNLABELLED: In the cohort of 123 patients (average age 44 years) criteria for glomerular and nonglomerular hematuria (H) were established by phase-contrast microscopy (PCM). According to literature, hematuria was divided into glomerular, mixed or nonglomerular if: > 60%, 20-60% and < 20% dysmorphic erythrocytes (E) of fresh morning urine sediment were found. Diagnosis of glomerulonephritis was confirmed by renal biopsy in 54/57 glomerular H as well as in all 8 cases of mixed H. On the contrary, urological reasons for H were found in 55/58 cases of nonglomerular H with normal renal biopsy in the remaining 3 patients. Using value > 20% of dysmorphic E as a new norm for glomerular H, we found sensitivity and specificity of this test as 100% and 95% respectively. IN CONCLUSION: glomerular H should be suspected and renal biopsy recommended when > 20% dysmorphic E are found by PCM what means exclusion of the term "mixed H".

Adolescent↗
PubMed1989

[Differentiation of hematuria by phase contrast microscopy studies of urine erythrocytes].

The results of phase-contrast microscopic investigations of urinary erythrocytes in 300 patients (120 patients with bioptical verified glomerulonephritis, 54 patients suffering from interstitial nephritis, 56 patients with urinary tract diseases and 70 healthy probands) are discussed. The portion of glomerular erythrocytes is dependent on diuresis, renal function and activity of glomerulonephritis. This non-invasive procedure is quick and easy practicable and its results are reliable (sensitivity and specifity of more than 90%). The proof of mainly glomerular erythrocytes save from instrumental and invasive diagnostic procedures in nephrological diseases, whereas non-glomerular erythrocytes may have an urological or hematological origin.

Adolescent↗
PubMed1989

Erythrocyte morphology under phase contrast microscopy in haematuria.

Fresh urine samples from twenty patients with macroscopic haematuria were examined by phase contrast microscopy to study the erythrocyte morphology. Other appropriate investigation like - renal biopsy in suspected glomerulonephritis and appropriate urological investigations in other cases to prove the site of origin of erythrocyte were done in all cases. Changes in erythrocyte morphology were observed in all the 12 patients with histological evidence of proliferative glomerulonephritis. These changes included extrusion of cell cytoplasm (39.5%), 'Doughnut' cell (26.5%) budding cell (15%) and cell membrane rupture with loss of cytoplasm (15%). Overall 83.3% of the erythrocytes showed some morphologic change or the other. In 8 patients where bleeding was into the pelvicalyceal system, ureter or bladder, 95% of RBCs showed no discernible morphologic change. It is concluded that the morphological changes in the erythrocyte identified under the phase contrast microscope can help to differentiate between glomerular and non glomerular causes of bleeding.

Adolescent↗
PubMed1987

Complete staining of human spermatozoa and immature germ cells combined with phase contrast microscopy.

A method combining Janus green B and Thymol blue stains the anterior part of the head, the nuclear membrane, middle piece, and tail of spermatozoa light green and the nucleus deep purple. The method provides excellent stained preparations for the evaluation of sperm morphology by phase contrast microscopy. It produces significantly less abnormal spermatozoa compared with the Papanicolaou stain.

Azo Compounds↗
PubMed2003

Comparison of red blood cell volume distribution curves and phase-contrast microscopy in localization of the origin of hematuria.

OBJECTIVES: To determine the ability, reliability, and accuracy of urinary red blood cell volume distribution curves obtained with the use of an autoanalyzer to identify the origin of isolated microscopic hematuria and compare the results with those obtained with phase-contrast microscopy (PCM). METHODS: A prospective evaluation was performed in 45 patients with glomerular or nonglomerular microhematuria detected by urinalysis, PCM, radiologic evaluation, endoscopy, and, sometimes, renal biopsy. Urine samples were analyzed in an electronic particle-size analyzer, and the tests were repeated to assess reliability. The kappa correlation coefficient was used to assess reliability and to compare the results with the final diagnosis and with those obtained with PCM. RESULTS: Of the 28 patients who had a single definite cause of hematuria, 16 had glomerular bleeding and 12 nonglomerular bleeding. The origin of hematuria was correctly identified by the autoanalyzer in 60.7% of cases. A statistically significant correlation was found with the final diagnosis (kappa = 0.433, P = 0.048). The reliability was excellent (kappa = 0.917, P <0.0001). Of 16 patients with glomerulonephritis, 10 (62.5%) were correctly identified by PCM and 14 (87.5%) by the autoanalyzer. In 12 patients with nonglomerular bleeding, PCM was accurate in 7 (58%) and the autoanalyzer in 3 (25%). The results were statistically correlated with the findings of PCM (kappa = 0.327, P <0.00001). CONCLUSIONS: The use of an autoanalyzer is easy, reproducible, and noninvasive. It provides reliable information to orient the diagnosis toward glomerular or nonglomerular bleeding. It is as accurate as PCM for screening for the source of hematuria.

Adult↗
PubMed1998

[Value of phase-contrast microscopy in the etiological diagnosis of hematuria in adults. Part II: Analysis of factors modifying morphology of erythrocytes in urine sediment].

In 41 patients with glomerular hematuria diagnosed by renal biopsy no correlation between intensity of tubulo-interstitial changes and range of dysmorphic erythrocytes (E) in phase-contrast microscopy (PCM) was found. However, such correlation existed in the case when acanthocytes in PCM were detected. From factors of potential influence on the morphology of E such as value of proteinuria, glomerular filtration rate, crystalluria, osmolarity and pH of urine, none had any significant role in changing the morphology of E of glomerular as well as of non-glomerular origin.

Adult↗
PubMed1987

Phase contrast microscopy of the urine sediment for the diagnosis of glomerular and nonglomerular bleeding-data in children and adults with normal creatinine clearance.

In a pediatric and in an adult group of patients with hematuria and normal creatinine clearance overnight urine examination was carried out on 2 nonconsecutive days by means of phase contrast microscopy by two independent observers working in two different institutions. In this way it was possible to distinguish between patients on the basis of dysmorphic (glomerular) and isomorphic (nonglomerular) red cells in urine and to correlate the findings with the final diagnosis. A clear-cut indication (more than 80% of isomorphic and/or dysmorphic red cells) was obtained in 163 patients (102 of pediatric age) and final diagnosis of hematuria correlated with red-cell microscopy findings in 96.4% of glomerular diseases and in all cases of nonglomerular origin. Mixed hematuria (50-75% of dysmorphic red cells) was found in 2 cases of renal tuberculosis, 2 cases of polycystic kidney disease and in 1 child with viral meningoencephalitis with a bladder stone. The data indicate that the method is safe and accurate but further experience must be gathered for the many etiologies of glomerular and nonglomerular diseases hitherto not studied.

Adolescent↗
PubMed1987

[Diagnosis of glomerular and non-glomerular erythrocyturia using phase contrast microscopy of the urine sediment].

Recently the appearance of deformed polymorphous erythrocytes in the urinary sediment has been described as characteristic of glomerular bleeding. We studied 30 patients with histologically confirmed glomerular disorders and 25 patients with urological diseases and with hematuria. In the sediment of 10 ml urine 200 erythrocytes were counted under phase-contrast microscopy and evaluated relative to their morphology. The number of glomerular erythrocytes was expressed as a percentage. In all groups of glomerular disorders (mesangial-proliferative, membranous and membrano-proliferative glomerulonephritis, focal segmental glomerulosclerosis, glomerulonephritis of systemic disease, thinning of the glomerular basement membrane) the percentage of glomerular erythrocytes varied widely between 2 and 100%. In 7 cases less than 10% of glomerular erythrocytes were found. There was no correlation between the percentage of glomerular erythrocytes and the degree of renal insufficiency, hematuria or proteinuria. On the other hand, in patients with hematuria from the lower urinary tract, erythrocytes were uniformly non-glomerular in shape (95-100%). We conclude that 10-20% or more of glomerular erythrocytes in the urinary sediment are a good indicator of glomerular disease, whereas lower figures do not definitely rule out a glomerular origin for hematuria.

Erythrocytes↗
PubMedDate not supplied

Precision and accuracy of asbestos fiber counting by phase contrast microscopy.

A new method was developed to prepare permanent asbestos slides with relocatable fields of view by imprinting these fields directly on the cleared wedges of filters containing asbestos fibers. The image quality of the fibers is comparable with that of the fibers prepared by the acetone/triacetin and the dimethyl formamide/Euparal method. The slides are suitable for evaluating the intercounter precision and accuracy of fiber counts by phase contrast microscopy. Seventeen chrysotile and 16 amosite slides, prepared from American Industrial Hygiene Association/National Institute for Occupational Safety and Health Proficiency Analytical Testing program samples, were evaluated by 58 analysts of 38 government and private laboratories in Canada. By asking the analysts to examine the same fields of view of the slides, the present study found that when examined at 400x, an average of 59.2 fiber counting errors were made for every 100 chrysotile fibers reported and 24.4 errors for 100 amosite fibers reported. The chrysotile fibers were underestimated by 25.0%, but there was no bias in counting amosite fibers. Remedial steps have been proposed to control the major source of errors, which is the subjective ability of the analyst to observe and size fibers. The slides may also be used to harmonize various phase contrast optical microscopy methods and proficiency testing programs.

Asbestos, Amosite↗
PubMed2003

[Identification of asbestos in bulk materials by polarised light microscopy and phase contrast--method and results].

The implementation of the 1997 law on the banned use of asbestos, entailing a successive elimination of asbestos products, is planned for 30 years. Asbestos identification in samples of bulk materials is essential before starting dismantling works. The presented method of asbestos identification by polarized light microscopy and phase contrast involves the study of the following optical parameters of asbestos fibers: color, morphology, refractive index, anisotropy, pleochroism, optic nature and extinguish angle. The major advantages of this method are: small material samples, short time of analysis, high asbestos sample detectability (0.1%) and high reliability of results. This paper presents the results of asbestos identification in over a dozen of samples of bulk materials derived from various buildings and installations.

Asbestos↗
PubMedDate not supplied

Phase contrast microscopy with modified Hansel's staining: mast cell identification and activity-related changes in cell membrane refractivity in allergic nasal smears.

BACKGROUND: A new technique called phase contrast microscopy with modified Hansel's staining (used with bright field microscopy) was developed to identify mast cells (MCs) and granulocytes (eosinophil/neutrophil/basophil [E/N/B]). METHODS: Nasal scratching smears from 618 patients with Japanese cedar pollinosis were examined using this new technique. RESULTS: This technique permitted accurate morphological identification. MCs can be discriminated from E/N/Bs. The surface of the cell membrane appeared as low refractile (lr), moderately refractile (mr), or high refractile (hr). This was caused by the light, which is not related to the phase difference, but rather originated from the difference in the refraction of the direct light. In specimens from the onset stage (i.e., 1-3 days after onset), lr-MC and mr/hr-E/N/B were dominant. In specimens from the early stage (i.e., 4-7 days after onset), lr-E/N/B significantly increased in number. CONCLUSION: The phospholipid bilayers of the cell membrane exhibit a phase transition after the onset, and phase refractivity of the cell membrane is closely related to the activity of the cell. This indicates that in the onset stage, MCs are already activated, whereas most of the E/N/Bs are not. In contrast, the latter cell types become activated subsequently in the early stage.

Adult↗
PubMed2005

[Intraepithelial cervical squamous lesions: comparison between PAP-test, colposcopy, phase contrast microscopy and histology; usefulness of their synergic use].

AIM: In the last 10 years the tumors of cervix have showed a significant reduction in incidence, while the preneoplastic lesions are increased (linked often to human papilloma virus [HPV] infection), and so it is enhanced the role of early diagnosis. METHODS: The Authors have examined 124 patients at colposcopy showing transformation zone anomalies and/or HPV infections. The patients have submitted to PAP-test, phase contrast microscopy and to biopsy. RESULTS: The analysis of our cases show oneself better sensitivity of colposcopy than cytologic exam, in particular in the diagnosis of low grade intraepithelial lesions (LSIL), corresponding to CIN 1 and HPV lesions. CONCLUSIONS: Phase contrast microscopy, by search of possible preneoplastic elements in the smear, is a complementary technique, and if performed systematically and by qualified operators allows to reduce furthermore false negative rate. The synergic use of tools allows to increase of number of intrecervical neoplasia diagnosis. The following cost's increase cannot be considered an obstacle and it is not should be necessary to counsel always the colposcopy in case of anomalous PAP smear revealed during screening.

Carcinoma, Squamous Cell↗
PubMed1983

Phase contrast microscopy of microbial aggregates in the gingival sulcus of Macaca mulatta. Subgingival plaque bacteria in macaca mulatta.

The objective of this study was to study the relationship of microbial aggregates in the subgingival crevice to changes in periodontal health in Macaca mulatta. The sample included 68 oral sites from 17 Rhesus monkeys of various ages. The periodontal health of each site was evaluated using Plaque and Gingival Indices and crevice depth measurement. The subgingival plaque samples were examined by phase contrast microscopy and recorded on 16 mm film. A Microbial Index was developed based on a qualitative estimate of the numbers of organisms, morphology of predominant organisms, and the presence or absence of motility. The Microbial Index was demonstrated to be simple in use and highly reproducible. The findings indicate that changes in the Microbial Index are consistent with tissue changes seen in the periodontal status in M. mulatta. From this preliminary study, the oral flora of adult M. mulatta appears to have sufficient similarities to human oral flora to be used as a microbial model for experimental periodontal disease research. Future studies to refine and confirm the validity of the Microbial Index are warranted. It may prove to be a useful tool to monitor the effect of various treatment modalities on the periodontal flora and to determine the presence or absence of active disease.

Animals↗
PubMed2001

Validity of wet-mount bacterial morphotype identification of vaginal fluid by phase-contrast microscopy for diagnosis of bacterial vaginosis in family practice.

The aim of this study was to determine the accuracy of a wet-mount bacterial morphology scoring (BMS) system and Nugent's Gram stain analysis for the diagnosis of bacterial vaginosis, using Amsel's criteria as the gold standard. The three diagnostic criteria were assessed independently The BMS diagnosis was based on a scoring system which weighed the number of small bacterial morphotypes regarded as typical of bacterial vaginosis against lactobacillary morphotypes in phase-contrast microscopy of wet-mount preparations. Three groups of non-pregnant women attending either because of vaginal discharge, other genitourinary symptoms, or for a routine check-up, and a group of pregnant women attending for antenatal care were studied. The diagnostic accuracy was measured by sensitivity, specificity, positive and negative predictive values, and likelihood ratio. The accuracy of the BMS diagnosis was substantially high in all of the examined groups (LR 15.4-20.3). The accuracy of the Gram stain diagnosis was lower (LR 7.6-10.9). In the total material, the accuracy of the BMS diagnosis was higher than that of the Nugent's Gram staining. Intra- and inter-observer reproducibility of all three criteria applied was high. We propose greater routine use of the new BMS diagnosis for point-of-care testing in family practice as well as in research and in microbiology laboratories.

Adult↗
PubMed1993

Phase contrast microscopy for identifying epidermal margins in unstained cryosections for Mohs micrographic surgery.

BACKGROUND: Mohs fresh tissue micrographic surgery has been accepted as the most reliable therapeutic modality for the eradication of recurrent cutaneous malignancies or those skin cancers that are difficult to treat otherwise. OBJECTIVE: We have developed a method to ascertain the presence of the epidermis and other edges in the tissue sections before staining the cryosections and microscopically searching them for cancer cells. METHODS: Our method for screening the cryosections for the epidermis can be done quickly and easily using relatively inexpensive phase contrast optics. RESULTS: Use of this method allows easy visualization of freshly cut cryosections, especially the presence of the epidermis and other edges of the tissue, in just a matter of seconds instead of a half hour to stain and recut the sections. CONCLUSIONS: Phase contrast microscopy and/or dark field illumination are instrumental in screening unstained cryosections for the presence of the tissue borders, especially the epidermis, before they are stained with hematoxylin and eosin. This method saves a great deal of time and effort both for the surgeon and the patient.

Epidermis↗