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1.
J Biomed Opt ; 24(3): 1-7, 2018 12.
Article in English | MEDLINE | ID: mdl-30569670

ABSTRACT

The reflection and transmission of coherent light from a biological system can yield information about its condition. In the case of blood exposed to the air, there is a change in the properties of the speckle patterns observed in the coagulation process. This can be studied by means of the rate of temporal variation, the contrast, and also the fractality of patterns. The fractality of the speckle pattern can be investigated by a fractal dimension, which can quantify a level of the complexity of platelet aggregation structure and a fibrin network formed in the process of blood coagulation. In addition, dynamic characteristics of a movement in blood also contain information on the progress of the coagulation process. Fractality and dynamic characteristics are investigated simultaneously for speckle patterns observed in the coagulation process of stored horse blood. Experimental results show the feasibility of the proposed method for detecting hemolysis and formation of platelet aggregation structure and the fibrin network during the coagulation process.


Subject(s)
Blood Coagulation/physiology , Diagnostic Imaging/methods , Image Interpretation, Computer-Assisted/methods , Lasers
2.
Int J Hematol ; 97(1): 43-9, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23212465

ABSTRACT

Positron emission tomography (PET) is used for staging and response evaluation in primary gastric lymphoma (PGL). However, the implications of [(18)F]-2-fluoro-2-deoxy-D-glucose ((18)F-FDG) uptake in PGL at first diagnosis have not been reported. The relationship between (18)F-FDG uptake and the expression of facilitative glucose transporters (GLUTs), hexokinase II (HK II), and Ki67, as well as malignant potential in PGL, was assessed in this study. We analyzed 23 patients with PGL [nine with diffuse large B-cell lymphoma (DLBCL); seven with high-grade mucosa-associated lymphoid tissue (MALT) lymphoma; and seven with low-grade MALT lymphoma]. The expression levels of GLUT1, GLUT3, HK II, and Ki67 were evaluated according to the percentage of positive area determined by immunohistochemistry. Standardized uptake values correlated significantly with pathological malignant potentials (low-grade/high-grade MALT lymphoma and DLBCL: p = 0.001-0.002), Ki67 (p < 0.001), and GLUT1 expression (p = 0.02). We determined that (18)F-FDG uptake is related to GLUT1 expression and tumor histological grade as well as Ki67 in PGL.


Subject(s)
Fluorodeoxyglucose F18/metabolism , Glucose Transporter Type 1/metabolism , Lymphoma, Non-Hodgkin/diagnosis , Lymphoma, Non-Hodgkin/metabolism , Multimodal Imaging , Positron-Emission Tomography , Stomach Neoplasms/diagnosis , Stomach Neoplasms/metabolism , Tomography, X-Ray Computed , Aged , Aged, 80 and over , Female , Gastroscopy , Glucose Transporter Type 3/metabolism , Hexokinase/metabolism , Humans , Ki-67 Antigen/metabolism , Lymphoma, Non-Hodgkin/pathology , Male , Middle Aged , Neoplasm Grading , Neoplasm Staging , Stomach Neoplasms/pathology
3.
Opt Lett ; 37(12): 2202-4, 2012 Jun 15.
Article in English | MEDLINE | ID: mdl-22739855

ABSTRACT

We present a method for optical identification of dielectric and metal nanoparticles in a liquid matrix using phase retrieval of reflectance with TE- and TM-polarized light. A formula is derived for extracting the effective complex dielectric function of a nanoparticle colloid based on different complex reflectance components. The phase retrieval is performed using the maximum entropy method. We observe excellent accuracy both for dielectric and metallic nanoparticles with volume fractions up to 10%.

4.
Pancreas ; 41(4): 535-540, 2012 05.
Article in English | MEDLINE | ID: mdl-22228048

ABSTRACT

OBJECTIVE: We aimed to compare perfusion computed tomography (CTP) characteristics of the normal pancreas with those of chronic pancreatitis (CP) and to examine the possibility of evaluating pancreatic exocrine function with CTP. METHODS: Thirty-two patients (control group, n = 18; CP group, n = 14) who completed the whole pancreas CT perfusion examination with 256-slice CT were studied. Four parameters, including perfusion (PF), peak enhancement intensity (PEI), time-to-peak (TTP), and blood volume (BV), were measured and compared between the control and CP groups, and between patients with and without exocrine pancreatic insufficiency (EPI) in the CP group. Pancreatic exocrine function was determined via serum trypsinogen. RESULTS: There was no significant difference between the distribution of PF, PEI, and BV in different pancreas regions, namely, the head, body, and tail (P > 0.05). PF, PEI, and BV of the CP group were significantly decreased, and TTP was significantly increased compared with the control group (P < 0.05). A significant decrease of PF, PEI, and BV and increase of TTP were observed in patients with EPI than in patients without EPI (P < 0.05). CONCLUSIONS: Perfusion CT is an appropriate imaging technique to diagnose CP and may be useful as a screening test to rule out early EPI.

5.
Clin Nucl Med ; 37(2): 152-7, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22228338

ABSTRACT

PURPOSE: The aim of this study was to compare endoscopic macroscopic classification with fluorine-18 fluorodeoxyglucose (F-18 FDG) uptake in gastric mucosa-associated lymphoid tissue (MALT) lymphoma and to investigate the usefulness of F-18 FDG positron emission tomography (PET) for diagnosing gastric MALT lymphoma. MATERIALS AND METHODS: Sixteen patients with gastric MALT lymphoma who underwent F-18 FDG PET and gastrointestinal imaging modalities were included in this study. Sixteen healthy asymptomatic participants undergoing both F-18 FDG PET and endoscopy for cancer screening were in the control group. We investigated the difference of F-18 FDG uptake between the gastric MALT lymphoma and the control group and compared the uptake pattern in gastric MALT lymphoma with our macroscopic classification. RESULTS: The endoscopic findings of 16 gastric MALT lymphoma patients were classified macroscopically as chronic gastritis-like tumors (n = 6), depressed tumors (n = 5), and protruding tumors (n = 5). Abnormal gastric F-18 FDG uptake was observed in 63% of tumors in the gastric MALT lymphoma group and 50% of cases in the control group. The median maximum standardized uptake values for gastric MALT lymphoma patients and control group were 4.0 and 2.6, respectively, the difference of which was statistically significant (P = 0.003). F-18 FDG uptake results were positive for all protruding tumors but only 50% for chronic gastritis-like tumors and 40% for depressed-type tumors. CONCLUSIONS: F-18 FDG PET may be a useful method for evaluating protrusion-type gastric MALT lymphoma. When strong focal or diffuse F-18 FDG uptake is detected in the stomach, endoscopic biopsy should be performed, even if the endoscopic finding is chronic gastritis.


Subject(s)
Endoscopy , Fluorodeoxyglucose F18 , Gastric Mucosa/diagnostic imaging , Gastric Mucosa/pathology , Lymphoma, B-Cell, Marginal Zone/classification , Lymphoma, B-Cell, Marginal Zone/diagnostic imaging , Positron-Emission Tomography , Adult , Aged , Aged, 80 and over , Case-Control Studies , Female , Humans , Lymphoma, B-Cell, Marginal Zone/pathology , Male , Middle Aged , Young Adult
6.
Kurume Med J ; 57(4): 91-100, 2011.
Article in English | MEDLINE | ID: mdl-21778670

ABSTRACT

This study aimed to compare the usefulness of multidetector row CT (MDCT), MR cholangiopancreatography (MRCP), and endoscopic ultrasonography (EUS) in diagnosing branch duct intraductal papillary mucinous neoplasms (IPMNs) of the pancreas. Imaging and pathological findings were retrospectively evaluated for 25 patients with branch duct IPMNs of the pancreas who underwent surgical resection (13 adenomas, 4 borderline lesions, and 8 carcinomas). MDCT and MRCP were performed on all 25 patients, whereas EUS was performed on 22 patients. MDCT and MRCP were used to identify features predictive of malignancy, including carcinoma, borderline lesions, and the presence of thickened irregular walls/septa or a solid mass. EUS was used to identify the presence of intramural nodules or a solid mass. Correlations between histopathology and maximum diameter of the main pancreatic duct (MPD) or cyst size detected by MDCT and MRCP were also examined. Presence of a solid mass was highly correlated with malignancy with all imaging methods (MDCT; P=0.001, MRCP; P=0.008, EUS; P<0.001, respectively). Presence of thickened irregular walls/septa on MDCT correlated well with malignancy (P=0.019). In contrast, presence of thickened irregular walls/septa on MRCP and intramural nodules on EUS did not correlate with malignancy. No significant correlation was found between malignancy and average maximum MPD diameter or cyst size (P>0.05), though values tended to be larger in malignant tumors. Our results suggest that the presence of thickened irregular walls/septa or a solid mass on MDCT are highly correlated with malignancy, and that MDCT is useful for diagnosis of branch duct IPMNs of the pancreas.


Subject(s)
Adenocarcinoma, Mucinous/diagnosis , Carcinoma, Pancreatic Ductal/diagnosis , Cholangiopancreatography, Magnetic Resonance/methods , Endoscopy/methods , Pancreas/pathology , Pancreatic Neoplasms/diagnosis , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Diagnostic Imaging/methods , Female , Humans , Male , Medical Oncology/methods , Middle Aged , Reproducibility of Results
7.
Clin Nucl Med ; 35(7): 505-9, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20548142

ABSTRACT

A 74-year-old woman had dysphagia and underwent esophagogastroduodenoscopy. A giant submucosal tumor was seen from the middle to the lower esophagus. Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG-PET/CT) was performed and F-18 FDG was found to accumulate in the submucosal tumor. The maximum standardized uptake value of the early phase was 4.93 and that of the delayed phase was 6.48. Gastrointestinal stromal tumor (GIST) was confirmed by both fine needle aspiration under endoscopic ultrasound and postoperative histopathologic findings. We stained the postoperative histopathologic specimen to investigate glucose transporter (GLUT) expression using immunohistochemistry, which revealed that GLUT-1 had a weak expression on membranes and GLUT-4 had a strong expression on membranes or in cytoplasm. GLUT-3 had no expression on membranes or in cytoplasm. Esophageal GIST is rare and the relationship between GLUT expression and F-18 FDG accumulation in GIST is probably rare.


Subject(s)
Esophageal Neoplasms/diagnostic imaging , Fluorodeoxyglucose F18 , Glucose Transport Proteins, Facilitative/metabolism , Positron-Emission Tomography , Tomography, Emission-Computed , Aged , Esophageal Neoplasms/metabolism , Female , Humans , Immunohistochemistry , Magnetic Resonance Imaging , Radiography
8.
Jpn J Radiol ; 28(3): 205-13, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20437131

ABSTRACT

PURPOSE: The aim of this study was to compare multidetector-row computed tomography (MDCT) findings between cases of sclerosing cholangitis with autoimmune pancreatitis (SC-AIP) and infiltrative extrahepatic cholangiocarcinoma (IEC). MATERIALS AND METHODS: We retrospectively assessed MDCT findings from 16 IEC cases and 13 SC-AIP cases. MDCT findings were analyzed with regard to location, length, wall thickness, contour, stricture wall enhancement pattern, proximal duct diameter, and the presence of diffuse concentric thickening in the proximal duct and gallbladder wall thickness. RESULTS: Stricture length, stricture wall thickness, and proximal duct diameter were significantly smaller for SC-AIP than for IEC: 19.3 +/- 8.7 vs. 31.8 +/- 12.0 mm (P = 0.004), 2.1 +/- 1.3 vs. 4.1 +/- 1.3 mm (P < 0.001), and 9.2 +/- 3.9 vs. 13.3 +/- 5.0 mm (P = 0.012), respectively. SC-AIP was correlated with stricture location in both the intrapancreatic and hilar hepatic bile ducts, concentric stricture contour (P < 0.001), and diffuse concentric thickening of the proximal bile duct (P = 0.010). Overall values of sensitivity, specificity, and accuracy used to distinguish between SC-AIP and IEC for stricture wall thickness of <3.0 mm and concentric contour were 76.9%, 93.8%, and 86.2%, respectively, and 100%, 87.5%, 93.1%, respectively. CONCLUSION: Concentric contour and stricture wall thicknesses of <3.0 mm may help distinguish between SC-AIP and IEC.


Subject(s)
Autoimmune Diseases/diagnostic imaging , Bile Duct Neoplasms/diagnostic imaging , Bile Ducts, Extrahepatic , Cholangiocarcinoma/diagnostic imaging , Cholangitis, Sclerosing/diagnostic imaging , Pancreatitis, Chronic/diagnostic imaging , Tomography, X-Ray Computed , Adult , Aged , Aged, 80 and over , Autoimmune Diseases/complications , Cholangitis, Sclerosing/complications , Female , Humans , Male , Middle Aged , Pancreatitis, Chronic/complications , Sensitivity and Specificity
9.
Gan To Kagaku Ryoho ; 37(4): 727-30, 2010 Apr.
Article in Japanese | MEDLINE | ID: mdl-20414036

ABSTRACT

We report a case of drug eruption (erythema multiforme type) in a 54-year-old woman, following concurrent chemoradiotherapy for squamous cell carcinoma of the anal canal. Chemotherapy comprised one cycle of mitomycin C 10 mg/m2/day (intravenous bolus injection)on day 1 and 5-fluorouracil(5-FU)1, 000 mg/m 2/day (continuous intravenous infusion) on days 1-4 of radiotherapy. External irradiation of the pelvic space was performed, using daily fractions of 1. 5 Gy(total dose, 33 Gy). From day 4 after chemoradiotherapy, erythema appeared proximal to the forearm site used for drug administration. On day 6, erythema was noted on the trunk, hip and thigh. We suspected erythema multiforme based on the appearance of wheals and target lesions of the skin and a patient history of chemoradiotherapy. Steroids were administered orally, which resolved systemic eruption at week 2. The patient also experienced grade 3 leukocytopenia, neutropenia, thrombopenia, diarrhea, and anorexia. Although we could not provide sufficient chemotherapy and radiation therapy due to severe side effects, squamous cell carcinoma of the anal canal responded extremely well with a marked decrease in complete response. We surmise that the drug eruption was associated with 5-FU. Concurrent chemoradiotherapy is safe and effective for squamous cell carcinoma of the anal canal, but care is required to prevent drug eruption during treatment.


Subject(s)
Anal Canal/pathology , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Carcinoma, Squamous Cell/drug therapy , Erythema Multiforme/chemically induced , Fluorouracil/adverse effects , Mitomycin/therapeutic use , Rectal Neoplasms/drug therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Squamous Cell/radiotherapy , Combined Modality Therapy/adverse effects , Erythema Multiforme/drug therapy , Female , Fluorouracil/administration & dosage , Fluorouracil/therapeutic use , Humans , Middle Aged , Mitomycin/administration & dosage , Mitomycin/adverse effects , Rectal Neoplasms/radiotherapy , Steroids/therapeutic use
10.
Opt Lett ; 34(23): 3743-5, 2009 Dec 01.
Article in English | MEDLINE | ID: mdl-19953181

ABSTRACT

Internationally standardized turbidity measurements for probing solid particles in liquid are problematic in the case of simultaneous light scattering and absorption. A method and a sensor to determine the turbidity in the presence of light absorption are presented. The developed sensor makes use of the total internal reflection of a laser beam at the liquid-prism interface, and the turbidity is assessed using the concept of laser speckle pattern. Using average filtering in speckle data analyzing the observed dynamic speckle pattern, which is due to light scattering from particles and the static speckle due to stray light of the sensor, can be separated from each other. Good correlation between the standard deviation of dynamic speckle and turbidity value for nonabsorbing and for absorbing liquids was observed. The sensor is suggested, for instance, for the measurement of ill-behaved as well as small-volume turbid liquids in both medicine and process industry.

12.
Nihon Shokakibyo Gakkai Zasshi ; 104(3): 373-80, 2007 Mar.
Article in Japanese | MEDLINE | ID: mdl-17337874

ABSTRACT

Thirty patients with intraductal papillary-mucinous tumor (IPMT) of the pancreas underwent multidetector-row CT (MD-CT) in addition to endoscopic retrograde pancreatography (ERP), and, in 27 cases magnetic resonance cholangiopancreatography (MRCP) and endoscopic ultrasonography (EUS). The usefulness of MD-CT was investigated by comparing various imaging methods of the communication from the main pancreatic duct (MPD) to patulous/bulging papilla in addition to the indices for benign or malignant disease, the degree of dilation of the MPD, localization and size of cystic lesions, and presence or absence of neoplastic lesions, such as thickened walls and septa, intramural nodule, solid mass. With MD-CT, dilation of the MPD and localization and size of cystic lesions were accurately assessed, even in patients with obstruction of the main pancreatic duct in whom ERP was difficult to perform regardless of the presence or absence of massive amount of mucus. MD-CT with reconstructive imaging, such as MPR imaging and CPR imaging, allowed us to assess communication with the MPD and patulous/bulging papilla easier than MRCP. In our study, MD-CT was useful in the evaluation of thickened walls and septa that are predictive factors of malignancy in IPMT.


Subject(s)
Adenocarcinoma, Mucinous/diagnosis , Carcinoma, Pancreatic Ductal/diagnosis , Diagnostic Imaging/methods , Pancreatic Neoplasms/diagnosis , Adult , Aged , Aged, 80 and over , Cholangiopancreatography, Endoscopic Retrograde , Cholangiopancreatography, Magnetic Resonance , Endosonography , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Tomography, X-Ray Computed
13.
Opt Express ; 15(12): 7415-22, 2007 Jun 11.
Article in English | MEDLINE | ID: mdl-19547065

ABSTRACT

It was shown in previous studies that, when a diffuser is illuminated by coherent light with an average spatial intensity distribution obeying a negative power function, the scattered field in the Fraunhofer diffraction region exhibits random fractal properties. The method employed so far for producing such fields has a disadvantage in that generated speckle intensities are low due to small transmittance of fractal apertures used in the illumination optics. To overcome this disadvantage, a generation of fractal speckles by means of a spatial light modulator is proposed. The principle is explained and experimental results are also shown.

14.
Ann Nucl Med ; 20(4): 317-20, 2006 May.
Article in English | MEDLINE | ID: mdl-16856576

ABSTRACT

We report a case of early gastric cancer and early colon cancer detected by positron emission tomography (PET) cancer screening. A 64-year-old male patient with an unremarkable past history except for hypertension and cerebrovascular disease underwent 18F-FDG PET for cancer screening. Images revealed increased uptake in the gastric antrum and sigmoid colon. Both areas appeared suspicious for neoplasm on subsequent fluoroscopy and endoscopy, and biopsies were positive for neoplasia at both sites. The gastric lesion was treated by distal gastrectomy and D2 lymphadenectomy and the colon cancer by endoscopic mucosal resection (EMR). Both surgical specimens were positive for cancer.


Subject(s)
Colonic Neoplasms/diagnostic imaging , Fluorodeoxyglucose F18 , Positron-Emission Tomography/methods , Stomach Neoplasms/diagnostic imaging , Humans , Incidental Findings , Male , Middle Aged , Radiopharmaceuticals
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