Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
J Nucl Med ; 37(9): 1444-8, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8790189

RESUMEN

UNLABELLED: Imaging results in patients with high-grade osteosarcoma of the extremities were reviewed to determine whether scintigraphic appearance correlated with histologic response to preoperative chemotherapy. METHODS: Histologically, the percent tumor necrosis in specimens from 30 patients were classified into three grades: grade 1 = necrosis less than 60%, grade 2 = 60%-89% necrosis and grade 3 = diffuse necrosis greater than 90% based upon whole transverse sections. Scintigraphically, we analyzed 201TI uptake before and after preoperative chemotherapy. The changes in the tumor-to-background ratio were defined by an alteration ratio. RESULTS: Of the 11 patients with a grade 1 response, the ratio showed -67.1% +/- 45.4% (mean +/- s.d.). Of the 9 patients with a grade 2 response, the ratio showed 37.9% +/- 29.9% of the 10 patients with a grade 3 response the ratio showed 105.5% +/- 12.4%. The ratios correlated well with the histologic grades (p < 0.0001; analysis of variance). CONCLUSION: Thallium-201 scintigraphy accurately assesses the effect of chemotherapy on osteosarcoma.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/tratamiento farmacológico , Osteosarcoma/diagnóstico por imagen , Osteosarcoma/tratamiento farmacológico , Radioisótopos de Talio , Adolescente , Adulto , Neoplasias Óseas/mortalidad , Quimioterapia Adyuvante , Niño , Femenino , Neoplasias Femorales/diagnóstico por imagen , Neoplasias Femorales/tratamiento farmacológico , Neoplasias Femorales/mortalidad , Humanos , Masculino , Osteosarcoma/mortalidad , Cintigrafía , Talio
2.
Ann N Y Acad Sci ; 972: 235-41, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12496023

RESUMEN

This paper deals with interaction between a bubble and fluid around it, visualized by a moving object flow image analyzer (MOFIA) consisting of a three-dimensional (3D) moving object image analyzer (MOIA) and two-dimensional particle image velocimetry (PIV). The experiments were carried out for rising bubbles of various sizes and shapes in stagnant water in a vertical pipe. In the MOFIA employed, 3D-MOIA was used to measure bubble motion and PIV to measure fluid flow. The 3D position and shape of a bubble and the velocity field were measured simultaneously. The experimental results showed that the interaction was characterized by the shape, size and density of a bubble. Concretely, they showed the characteristics of bubble motion, wake shedding, and flow field.

3.
Neuroreport ; 11(10): 2151-5, 2000 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-10923661

RESUMEN

We investigated the effects of l-menthol on cultured dorsal root ganglion (DRG) cells, instead of free nerve endings of sensory fibers. Using Fura-2 microfluorimetry, we identified a few DRG neurons that showed an increase in intracellular free Ca2+ concentration ([Ca2+]i) in response to l-menthol. They made up only 10% of the neurons activated by a high K+ solution. l-Menthol induced the [Ca2+]i increase in a dose-dependent manner, with an EC50 of 37.9 microM and a Hill coefficient of 0.97. A related compound, cyclohexanol, had no effect. When extracellular Ca2+ was removed, l-menthol did not induce the [Ca2+]i increase. Whole-cell current-clamp recordings revealed that l-menthol induced depolarization (13.2 mV, receptor potential) leading to impulses. We conclude that l-menthol induced the impulses through activation of menthol receptors in a small subset of the cultured sensory neurons.


Asunto(s)
Calcio/metabolismo , Mentol/farmacología , Neuronas Aferentes/fisiología , Animales , Células Cultivadas , Relación Dosis-Respuesta a Droga , Ganglios Espinales/citología , Ganglios Espinales/fisiología , Cinética , Potenciales de la Membrana/efectos de los fármacos , Neuronas Aferentes/citología , Neuronas Aferentes/efectos de los fármacos , Técnicas de Placa-Clamp , Potasio/farmacología , Ratas , Ratas Wistar
4.
Ann Nucl Med ; 8(1): 55-64, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8204398

RESUMEN

The purpose of this study was to investigate Tl-201 as a tumor scanning agent in patients with malignant soft tissue sarcomas and to establish the sensitivity of this type of scintigraphy concerning local recurrences or metastases that may remain clinically suspected. Seventy-eight patients with malignant soft tissue sarcomas and 22 with benign soft tissue tumors were studied. Of these 78 malignant soft tissue sarcomas patients, the sensitivity of Tl-201 (81.2%) was higher than that of Ga-67 (68.8%). Thirty-three out of 78 patients received a total of 95 consecutive scintigraphic follow-up examinations. Therapeutic effects was assessed by comparing the results of Tl-201 examinations with the clinical findings. Of these 33 patients, the therapeutic effects observed were as follows: complete remission 1, partial remission 8, progress of disease 1, and no remarkable change 23. Tl-201 scintigraphy has proved itself very useful not only in clinically detecting the malignant soft tissue sarcomas and in assessing therapeutic effects on these diseases, but also in assessing the follow-up patients with malignant soft tissue sarcomas.


Asunto(s)
Sarcoma/diagnóstico por imagen , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Radioisótopos de Talio , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Radioisótopos de Galio , Histiocitoma Fibroso Benigno/diagnóstico por imagen , Humanos , Leiomiosarcoma/diagnóstico por imagen , Liposarcoma/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Neurofibrosarcoma/diagnóstico por imagen , Cintigrafía , Estudios Retrospectivos , Sarcoma Sinovial/diagnóstico por imagen , Sensibilidad y Especificidad
5.
Ann Nucl Med ; 6(4): 247-51, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1336964

RESUMEN

This study was undertaken to evaluate the use of Indium-111-labeled leukocyte (111In-WBC) imaging compared with Technetium-99m pertechnetate (99mTcO4-) imaging in 19 patients with rheumatoid arthritis (RA) and 8 with osteoarthritis. Knee and wrist joints were evaluated for both radionuclides. The results indicated a good correlation of the clinical assessment of pain and swelling with joint uptake ratio (JUR) between 111In-WBC and 99mTcO4- in RA and osteoarthritis patients. We observed a discrepancy in both imagings in "burned out" cases. It was concluded that a JUR of 111In-WBC could distinguish active RA from inactive RA or osteoarthritis at a value of 1.15 and that the use of 111In-WBC was a more reliable procedure than 99mTcO4-.


Asunto(s)
Artritis Reumatoide/diagnóstico por imagen , Radioisótopos de Indio , Leucocitos , Osteoartritis/diagnóstico por imagen , Pertecnetato de Sodio Tc 99m , Adulto , Anciano , Femenino , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Cintigrafía , Articulación de la Muñeca/diagnóstico por imagen
6.
Angiology ; 43(11): 925-32, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1443766

RESUMEN

To achieve the visualization of regional lymph nodes by lymphoscintigraphy, 21 patients with head-and-neck cancer were studied with the aid of 99mTc-labeled rhenium sulfur colloid (99mTc Re). Four injection sites were selected; the injections were given into the subcutaneous tissue of the parietal area of 11 patients, into the submucosa of the retromolar area of 6 patients, into the subcutaneous tissue of the postauricular area of 2 patients, and into the thyroid glands of 2 patients. Lymphoscintigraphy was done three hours after the injection. The cervical regions were visible in 85.7% of the patients on the affected side and in 90.5% on the healthy side. The visualization comprised the following regions: submental, submandibular, deep cervical, accessory, and supraclavicular regions. In total, 102 nodes were visualized on the affected side (average 4.8 per patient) and 110 nodes in the healthy side (average 5.5). Histologically, 15 of 21 patients had lymph nodes metastases and 6 did not. Of these 21 patients, 66.7% (14/21) had confirmed lymph node metastases in the visualized regions. This technique appears to be a relatively easy and efficient method of imaging the regional lymph nodes in head-and-neck cancer both before treatment and after neck surgery.


Asunto(s)
Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Ganglios Linfáticos/diagnóstico por imagen , Compuestos de Tecnecio , Anciano , Coloides , Terapia Combinada , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/terapia , Humanos , Metástasis Linfática , Masculino , Cuello , Disección del Cuello , Cintigrafía , Renio , Tecnecio
7.
Clin Nucl Med ; 22(1): 38-41, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8993872

RESUMEN

Tc-99m pertechnetate scintigraphy was compared with Tl-201 chloride and Ga-67 citrate to evaluate the avidity of Tc-99m pertechtate for malignant soft-tissue tumors. Twenty-three patients with malignant soft-tissue tumors underwent scintigraphic studies. All 23 received Tc-99m and Tl-201, whereas 14 also were injected with Ga-67. In 21 (91%) of the 23 patients, Tc-99m accumulated extensively in the tumors. Tl-201 accumulated in 12 (52%) of the 23 tumors. Ga-67 accumulated in only 5 (36%) of the 14 tumors. The avidity of Tc-99m for myxoid tumors was markedly different from the other two agents. Tc-99m accumulated in all eight myxoid tumors, while neither Tl-201 or Ga-67 showed marked accumulation except for one patient with increased accumulation of Tl-201. This study shows that Tc-99m pertechnetate has the potential to localize malignant soft-tissue tumors and may be useful in the evaluation of these tumors.


Asunto(s)
Radioisótopos de Galio , Pertecnetato de Sodio Tc 99m , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Radioisótopos de Talio , Extremidades , Femenino , Histiocitoma Fibroso Benigno/diagnóstico por imagen , Humanos , Liposarcoma/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Cintigrafía , Estudios Retrospectivos
8.
Masui ; 48(9): 1011-3, 1999 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-10513179

RESUMEN

A decrease in urinary volume during surgery is often encountered. Usually it can be treated with intravenous fluid or diuretics. We here report a rare case of intraoperative anuria in which renal blood flow ceased totally. The patient was 36 year old female (166 cm 50 kg), who was admitted for a investigations of long-term severe hypertension of unknown origin. Radiographic examination showed no adrenal tumor but a right ovarian cyst was found and suspected to be malignant, for which oophorectomy was indicated. After epidural catheterization, general anesthesia was induced by intravenous propofol and vecuronium, and maintained with epidural lidocaine and the inhalation of isoflurane and nitrous oxide mixed with oxygen. During surgery, urinary outflow decreased gradually leading to total anuria, which was resistant to intravenous fluid and furosemide. Intraoperative pyelography was performed and both kidneys and urinary tracts were not visualized. After the surgery, when the patient returned to the ward, urine began to flow. Postoperative pathological examination of the removed ovary showed a presence of renin excreting tumor cells. The anuria was considered to be the result of transient spastic obstruction of bilateral renal arteries, presumably in response to a high level of plasma renin.


Asunto(s)
Anuria/etiología , Histerectomía , Complicaciones Intraoperatorias/etiología , Ovariectomía , Obstrucción de la Arteria Renal/etiología , Adulto , Anestesia General , Femenino , Humanos , Neoplasias Ováricas/cirugía
11.
Br J Cancer ; 97(11): 1493-8, 2007 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-18040274

RESUMEN

(18)F-2-deoxy-2-fluoro-glucose Positron Emission Tomography (FDG-PET) has been recently proposed as a promising cancer-screening test. However, the validity of FDG-PET in cancer screening has not been evaluated. We investigated the sensitivity of FDG-PET compared with upper gastric endoscopy in gastric cancer screening for asymptomatic individuals. A total of 2861 consecutive subjects (1600 men and 1261 women) who were asymptomatic and who underwent both FDG-PET and upper gastrointestinal endoscopy between 1 February 2004 and 31 January 2005 were included in this study. Both endoscopists and a radiologist were unaware of the results of the other diagnostic tests. The FDG-PET images were examined using criteria determined by the pattern of FDG accumulation. Sensitivity and specificity of FDG-PET were calculated compared with endoscopic diagnosis as the gold standard. Among 2861 subjects enrolled in the study, there were 20 subjects with gastric cancer, of whom 18 were T1 in depth of cancer invasion. Positive FDG-PET results were obtained only in 2 of the 20 cancer subjects. The calculated sensitivity and specificity for overall gastric cancers were 10.0% (95% confidence interval (CI): 1.2-31.7%) and 99.2% (95% CI: 98.8-99.5%), respectively. (18)F-2-deoxy-2-fluoro-glucose Positron Emission Tomography was poorly sensitive for detection of gastric cancer in the early stages.


Asunto(s)
Endoscopía Gastrointestinal/métodos , Fluorodesoxiglucosa F18 , Tomografía de Emisión de Positrones/métodos , Neoplasias Gástricas/diagnóstico , Anciano , Femenino , Humanos , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
12.
Nihon Igaku Hoshasen Gakkai Zasshi ; 52(4): 491-6, 1992 Apr 25.
Artículo en Japonés | MEDLINE | ID: mdl-1630894

RESUMEN

111In labelled leukocyte scintigraphy (ILLS) was performed in five patients with hepatic abscess. For the accurate diagnosis of hepatic abscess, ILLS was superimposed on 99mTc phytate liver scintigraphy. The results of ILLS were compared with CT and US findings. Four of five patients (80%) showed abnormal accumulations in the liver. The smallest abscess detected was 46 mm x 43 mm. CT scan showed rim enhancement, which was a specific finding for hepatic abscess, in three patients. It was rather difficult to diagnose hepatic abscess by US. In two cases without definite rim enhancement on CT, the abscesses were diagnosed as hot spots by ILLS. We conclude that ILLS combined with 99mTc liver scintigraphy is useful for the diagnosis of hepatic abscess.


Asunto(s)
Radioisótopos de Indio , Leucocitos/diagnóstico por imagen , Absceso Hepático/diagnóstico por imagen , Hígado/diagnóstico por imagen , Anciano , Niño , Femenino , Humanos , Hígado/patología , Masculino , Persona de Mediana Edad , Cintigrafía , Tomografía Computarizada por Rayos X , Ultrasonografía
13.
Skeletal Radiol ; 24(5): 331-6, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7570152

RESUMEN

The purpose of this study was to investigate technetium-99m pertechnetate (Tc-99m) as a tumor-scanning agent in patients with extra-abdominal fibromatosis, and to establish the sensitivity of this type of scintigraphy. Eleven patients with extra-abdominal fibromatosis were studied: all but one having postsurgical recurrences. Of the 11 patients, diagnosed histologically, 5 underwent repeated Tc-99m scintigraphic follow-up examinations. The injected 370 MBq Tc-99m gave us an early scintigram within 10 min and a delayed one 2 h later. For adequate comparison, the region of interest (ROI) of the scintigram was placed over the tumor. The tumor-to-background (T/BG) count ratio was computed. Extra-abdominal fibromatoses, even recurrences, were demonstrated scintigraphically in both the early and the delayed phase, in all 11 patients. The average T/BG ratio was 2.11 in the early scintigram and 2.15 in the delayed one. The sensitivity and the specificity were both 100%. Tc-99m scintigraphy has proved useful in detecting extra-abdominal fibromatoses and in the follow-up of patients.


Asunto(s)
Fibroma/diagnóstico por imagen , Pertecnetato de Sodio Tc 99m , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Adulto , Femenino , Fibroma/patología , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/patología , Valor Predictivo de las Pruebas , Cintigrafía , Sensibilidad y Especificidad , Neoplasias de los Tejidos Blandos/patología
14.
Cardiovasc Intervent Radiol ; 13(6): 384-6, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2126998

RESUMEN

With the use of a new improved coaxial catheter system, superselective hepatic catheterization has become easier. The improvements consist of a decrease in the outer and an increase in the inner diameters of the coaxial catheters from 0.98 to 0.96 mm and from 0.55 to 0.65 mm, respectively, and thickening of core guidewire material from 0.014 inch (0.35 mm) to 0.018 inch (0.40 mm). With this new catheter system, it is possible to inject contrast medium (iopamidol 300) at a higher rate (3 ml/sec) and gelatin sponge particles instead of gelatin powder for arterial embolization. The success rates for superselective catheterization using conventional (n = 10 procedures) and the improved coaxial catheter systems (n = 7) were 30% and 86%, respectively.


Asunto(s)
Cateterismo/instrumentación , Arteria Hepática , Cateterismo/métodos , Femenino , Arteria Hepática/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Radiografía
15.
Acta Radiol ; 31(6): 575-7, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2278780

RESUMEN

In 3 patients with primary hepatic malignancies, a communication between the right gastric vein and the left portal vein system was recognized at angiography. The right gastric vein entered directly into the left lateral portal veins in 2 patients and into the left medial portal veins in one. Portal angio-CT performed in one patient demonstrated a specific defect only in the left lateral superior area of the liver, consistent with the segmental opacification of the portal vein branch recognized on the angiogram. This rare communication was seen in 3 (1.5%) of 200 consecutive patients who underwent celiac angiography and is most likely an anomaly in which the right gastric vein directly enters the left portal vein instead of the portal vein trunk. When interpreting a filling defect not associated with a mass lesion on portal angio-CT for hepatic neoplasms or the right gastric vein communicating with the left portal vein system on the angiogram, this particular anomaly should be considered.


Asunto(s)
Vena Porta/anomalías , Estómago/irrigación sanguínea , Venas/anomalías , Adulto , Anciano , Angiografía , Anomalías Congénitas/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad
16.
Solid State Nucl Magn Reson ; 11(3-4): 169-75, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9694383

RESUMEN

A solid state NMR method is presented for determination of a backbone dihedral angle phi in peptides, being based on the previously reported method, relayed anisotropy correlation (RACO) NMR [Y. Ishii et al., Chem. Phys. Lett. 256 (1996) 133]. In the present method, the 15N-1H and the 13C-1H dipolar tensors in the 1H-15N-13C-1H system are two-dimensionally (2D) correlated via polarization transfer from 15N to 13C under magic angle spinning (MAS). This method was applied to N-acetyl[1,2-13C,15N]D,L-valine, and the H-C-N-H dihedral angle was determined to be 154.0 +/- 1.4 degrees or 206.0 +/- 1.4 degrees, the former agreeing with the X-ray value of 154 +/- 5 degrees.


Asunto(s)
Resonancia Magnética Nuclear Biomolecular/métodos , Péptidos/química , Anisotropía , Humanos
17.
Nihon Igaku Hoshasen Gakkai Zasshi ; 51(8): 942-9, 1991 Aug 25.
Artículo en Japonés | MEDLINE | ID: mdl-1945776

RESUMEN

The helical scanning CT unit, in which an X-ray tube continuously rotates at the rate of one revolution per second with constant movement of the table on which the patient is placed, was clinically tested in scanning of upper abdomen. Quality of the images obtained was equal to that of conventional CT. The images were particularly good at an X-ray beam width of 5 mm and table movement of 5 mm/sec with scan parameters of 120 kvp, 200 mA. Because of limitation of the X-ray tube capacity. X-ray beam width of 5 mm and table movement of 10 mm/sec with scan parameters of 120 kvp, 150 m, would be the most appropriate clinically. Application of the helical scanning CT will result in examination times shorter than in the case of conventional high-resolution CT and be obtained images at early vascular enhancement phase through the whole scanning area, so that it can be expected to be extremely useful in clinical diagnosis involving upper abdomen.


Asunto(s)
Radiografía Abdominal , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
18.
Gan No Rinsho ; 35(5): 554-9, 1989 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-2716187

RESUMEN

Using 24 lung cancer patients (20 males and 4 females) who had received radiotherapy, a multivariate analysis has been performed in relation to 19 factors suspected of exerting an effect on natural killer (NK) cell activity. As influencing factors, two factors of the disease, the stage (p less than 0.05) and the leukocyte count (p less than 0.08), were calculated to be significant. In the univariate analysis, the NK activity was found to be significantly low (p less than 0.05) when the leukocyte count was 7,000 or higher. In addition, patients who had died during the course of radiotherapy showed an NK activity which was significantly lower (p less than 0.05) than the activity manifested in both the disease-free patients and the relapsed progressive disease patients. Moreover, the patients with a PS of 40% or less had a significantly lower NK activity than the patients with a PS of 50% or more, though no correlation was found between the NK activity and the disease stage. In the use of this radiotherapy, the NK activity was found to be more strongly influenced by the size of the irradiated field than by the irradiated dose.


Asunto(s)
Células Asesinas Naturales/inmunología , Neoplasias Pulmonares/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Femenino , Humanos , Recuento de Leucocitos , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/radioterapia , Masculino , Persona de Mediana Edad , Pronóstico , Dosificación Radioterapéutica , Análisis de Regresión
19.
Nihon Gan Chiryo Gakkai Shi ; 24(3): 592-600, 1989 Mar 20.
Artículo en Japonés | MEDLINE | ID: mdl-2768971

RESUMEN

NK activity in patients with head and neck neoplasms treated with radiation and chemotherapeutics was studied on the influence of 19 factors by using the method of multiregression analysis. Of these factors, BUN, WBC, the size of radiation portal, chemotherapy, radiation doses, total protein (T.P.), age and GOT were significantly influenced on the fluctuation of NK activity (p less than 0.05). In the studies of the size of radiation portal and its doses, NK activity showed a tendency to increase with radiation dose in small size of radiation portal and a tendency to reduce in large size of it.


Asunto(s)
Neoplasias de Cabeza y Cuello/inmunología , Células Asesinas Naturales/inmunología , Adulto , Anciano , Terapia Combinada , Femenino , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica , Análisis de Regresión
20.
AJR Am J Roentgenol ; 164(4): 885-90, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7726041

RESUMEN

OBJECTIVE: The purpose of this study was to determine the sensitivity of CT in detecting early hepatocellular carcinoma and to evaluate its CT appearance. An early hepatocellular carcinoma is a nodular lesion with no fibrous capsule composed of well-differentiated tumor histologically. It differs from a small hepatocellular carcinoma, which is an overt tumor that is moderately to poorly differentiated and has a fibrous capsule. Size is not a criterion for distinguishing between early and small hepatocellular carcinomas. MATERIALS AND METHODS: Thirty-one patients with 39 histopathologically proved early hepatocellular carcinomas (mean diameter, 1.7 cm) found by sonography, MR imaging, and/or intraoperative sonography were included in a retrospective study. We reviewed unenhanced CT scans of the entire liver in 30 patients (37 lesions) and early and late (35 sec and 5 min after the beginning of injection of contrast material) contrast-enhanced CT scans of the entire liver in all 31 patients (table incremental CT in 21; helical CT in 10; 39 lesions). Eighteen histologically proved small hepatocellular carcinomas (< or = 3 cm; mean diameter, 2.3 cm), present in the same patients, served for comparison. Histopathologically, nine patients had chronic hepatitis, and 22 had cirrhosis. RESULTS: The overall sensitivity of CT in detecting early hepatocellular carcinoma was 56%. These tumors were usually isodense with respect to surrounding liver on unenhanced, early enhanced, and late enhanced CT scans (iso-iso-iso). This pattern was seen in 17 (46%) of 37 lesions; thus, these 17 histologically proved early hepatocellular carcinomas were not detected with CT. An iso-iso-low density pattern was recognized in eight (22%), a low-low-low pattern in seven (19%), and several different patterns in five (13%) of the 37 lesions. Only two (5%) of 39 early hepatocellular carcinomas had a high-density appearance on early enhanced CT scans. In comparison, the most common pattern of small overt hepatocellular carcinomas on CT scans was low-high-low, seen in 17 lesions (94%) detected with CT. When the density of lesions on unenhanced CT scans was compared with the histopathologic appearance of the masses, low-density lesions showed mild to moderate fatty change and isodense lesions showed no or minimal fatty change (p = .006). CONCLUSION: The sensitivity of CT in detecting early hepatocellular carcinoma is poor (56%). However, the diagnosis of early hepatocellular carcinoma should be considered if CT scans show a small lesion with an iso-low or low-low density enhancement pattern on early and late contrast-enhanced CT scans, respectively, in patients with chronic liver disease.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Anciano , Carcinoma Hepatocelular/patología , Medios de Contraste , Femenino , Humanos , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA