RESUMEN
BACKGROUND: The diagnostic value of perfusion CT in dementia patients was retrospectively evaluated in comparison to the Mini-Mental State Examination (MMSE). MATERIAL AND METHODS: The perfusion CT database of 55 subjects was investigated. All patients underwent an unenhanced, contrast-enhanced, and perfusion CT of the head. The clinical evaluation of the degree of dementia was performed with the MMSE. In the perfusion CT data, 24 ROI were marked. Then blood volume (BV), blood flow (BF), and mean transit time (MTT) were calculated and compared with the ipsilateral and contralateral regions and with the degree of dementia. RESULTS: With increasing degree of dementia, a significant decrease of the occipital and temporal BV was found. A significant decrease of the BF in the frontal lobe, basal ganglia, and occipital region was found. Concurrently, the MTT increased significantly in the basal ganglia region. The group with Alzheimer's disease showed significant regional hypoperfusion compared with the group of cognitively normal subjects in the frontal, basal ganglia, occipital, and temporal region. CONCLUSIONS: The cerebral perfusion decreased with increasing degree of dementia. The inexpensive and widely available perfusion CT reveals information about regional differences of cerebral perfusion, which may be useful in differentiating severity and types of dementia.
Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Isquemia Encefálica/diagnóstico por imagen , Encéfalo/irrigación sanguínea , Angiografía Cerebral/métodos , Demencia Vascular/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Tomografía Computarizada Espiral/métodos , Anciano , Anciano de 80 o más Años , Ganglios Basales/irrigación sanguínea , Velocidad del Flujo Sanguíneo/fisiología , Volumen Sanguíneo/fisiología , Corteza Cerebral/irrigación sanguínea , Diagnóstico Diferencial , Dominancia Cerebral/fisiología , Femenino , Humanos , Masculino , Escala del Estado Mental/estadística & datos numéricos , Psicometría , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
PURPOSE: To evaluate the feasibility of TIPS for portal vein thrombosis (PVT) with/without portal vein occlusion/cavernomatous transformation and with/without underlying cirrhosis. MATERIALS AND METHODS: 13 patients with PVT and refractory ascites (n=7) and variceal bleeding (n = 6) received TIPS placement. The function of the TIPS was controlled with Doppler US at 1 day, 1 week, 4 weeks and 4 months after TIPS placement and subsequently every 3 months. The rates of technical success, revision and mortality after TIPS were evaluated. RESULTS: The TIPS was successfully placed in 85% (11/13) of the cases. TIPS placement was successful in 87.5% (7/8) of patients with occlusion of the right portal vein and in 100% (5/5) of patients with non-occlusive right portal vein (p > 0.05), in 80% (8/10) of cirrhotic (x/10) and in 100% (3/3) of non-cirrhotic patients (p > 0,05), as well as in one patient with a fresh PVT and in 1 of 2 patients with cavernous transformation. 30 and 14.3% of patients needed a TIPS revision in the first and second year, respectively. No patient with occlusion of the right portal vein required a revision. 54.5% (6/11) of patients died within 6 months. Under exclusion of 4 patients with advanced malignant diseases, the mortality rate was 28.6%. CONCLUSION: TIPS should be considered for selected patients with symptomatic occlusive PVT with/without cavernous transformation and with/without underlying cirrhosis. The frequency of TIPS revision is not greater, and the mortality rate 6 months after PVT recanalization seems to be comparable with that of patients without PVT.
Asunto(s)
Síndrome de Budd-Chiari/cirugía , Várices Esofágicas y Gástricas/cirugía , Hemorragia Gastrointestinal/cirugía , Cirrosis Hepática Alcohólica/cirugía , Flebografía , Vena Porta , Derivación Portosistémica Intrahepática Transyugular/métodos , Trombosis/cirugía , Adulto , Anciano , Síndrome de Budd-Chiari/diagnóstico por imagen , Síndrome de Budd-Chiari/mortalidad , Circulación Colateral/fisiología , Embolización Terapéutica/métodos , Várices Esofágicas y Gástricas/diagnóstico por imagen , Várices Esofágicas y Gástricas/mortalidad , Femenino , Hemorragia Gastrointestinal/diagnóstico por imagen , Hemorragia Gastrointestinal/mortalidad , Hemangioma Cavernoso/diagnóstico por imagen , Hemangioma Cavernoso/mortalidad , Hemangioma Cavernoso/cirugía , Humanos , Cirrosis Hepática Alcohólica/diagnóstico por imagen , Cirrosis Hepática Alcohólica/mortalidad , Masculino , Persona de Mediana Edad , Vena Porta/diagnóstico por imagen , Vena Porta/cirugía , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/mortalidad , Complicaciones Posoperatorias/cirugía , Reoperación , Tasa de Supervivencia , Trombosis/diagnóstico por imagen , Trombosis/mortalidad , Resultado del TratamientoRESUMEN
The aim of this study is to evaluate the radiation dose to the interventional radiologist in transjugular intrahepatic portosystemic shunt (TIPS) concerning the risk of cancer and deterministic radiation effects and the relation to recommended dose limits. In 18 TIPS interventions radiation doses were measured with thermoluminescence dosemeters (TLD) fixed at the eyebrow, thyroid and hand of the radiologist without special lead shielding of these body parts and at the chest, abdomen and testes under the lead apron. The doses of the eye lens, thyroid gland and hand were assumed to be equal to the corresponding surface doses. The dose at the abdomen under the lead apron was used as an estimation of the ovarian dose. Effective dose equivalent was estimated by Webster's method. The estimated effective dose equivalent was 0.087 mSv and the effective dose 0.110 mSv. The risk of fatal cancer was of 10(-6) and the risk of severe genetic defect of 10(-7) for one single intervention. The maximum permissible number of TIPS interventions was 181, otherwise the dose limit for effective dose would be exceeded. When the radiologist performed more than 372 TIPS procedures per year for many years, the dose to the lens of the eye could exceed the threshold for cataract. If the interventionist performs a large number of TIPS procedures in a year, the risk of fatal cancer and developing cataracts becomes relatively high.
Asunto(s)
Neoplasias Inducidas por Radiación/etiología , Enfermedades Profesionales/etiología , Exposición Profesional/efectos adversos , Derivación Portosistémica Intrahepática Transyugular , Radiología , Femenino , Humanos , Masculino , Concentración Máxima Admisible , Persona de Mediana Edad , Dosis de Radiación , Protección Radiológica , Radiografía Intervencional , Radiometría , Medición de Riesgo , Factores de RiesgoRESUMEN
PURPOSE: To determine the values of effective dose and partial body dose for the radiologist and the assistant during transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC) und to compare the doses with the dose limits. MATERIALS AND METHODS: In 65 TACE of HCC cases, values of various surface doses for the radiologist and the assistant were measured. The measurements were performed with the help of thermoluminescence dosemeters (TLD) that were attached to the eyebrows, over the lobes of the thyroid gland, to the breasts, abdomen and symphysis, and to the hands and the lower legs. The measured surface dose values were used as indicators of the exposure of the organs and tissues located near the surface, i. e. eye lens, thyroid gland, breast, testes and tibia. They were also seen as conservative estimations of tissues deep inside the body and the extremities. RESULTS: The highest surface dose for the radiologist was measured at the lower leg (0.58 +/- 0.28 mSv) and the highest surface dose for the assistant was measured at the right lower leg (0.24 +/- 0.20 mSv) since it was closer to the tube than the left side, followed by the dose values at the also unprotected areas of the eyebrows, lobes of the thyroid gland and the hands. The estimated value of the effective dose was 0.06 +/- 0.03 mSv for the radiologist and 0.04 +/- 0.01 mSv for the assistant. With regard to the relationship between the dose limits according to the German X-ray regulation and the measured values and with regard to the maximum possible number of interventions per year, the partial body dose of the red bone marrow in the lower leg provided the greatest limitation, followed by the partial body dose of the muscle in the lower leg and the effective dose. CONCLUSION: In order to meet the dose limits, especially the lower leg should be protected, and the effective dose should also be reduced.
Asunto(s)
Empleos Relacionados con Salud , Quimioembolización Terapéutica/estadística & datos numéricos , Neoplasias Hepáticas/diagnóstico por imagen , Exposición Profesional/estadística & datos numéricos , Radiología , Medición de Riesgo/métodos , Recuento Corporal Total/estadística & datos numéricos , Antineoplásicos/administración & dosificación , Carga Corporal (Radioterapia) , Femenino , Alemania/epidemiología , Humanos , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/terapia , Masculino , Concentración Máxima Admisible , Persona de Mediana Edad , Exposición Profesional/análisis , Dosis de Radiación , Monitoreo de Radiación/métodos , Radiografía , Efectividad Biológica Relativa , Factores de RiesgoRESUMEN
Portal vein thrombosis (PVT) is diagnosed by imaging methods. Once diagnosed by means of ultrasound, Doppler ultrasound can be performed to distinguish between a benign and malignant thrombus. If further information is required, magnetic resonance angiography or contrast-enhanced computed tomography is the next step, and if these tests are unsatisfactory, digital subtraction angiography should be performed. Many papers have been published dealing with alternative methods of treating PVT, but the material is fairly heterogeneous. In symptomatic non-cavernomatous PVT, recanalization using local methods is recommended by many authors. Implantation of transjugular intrahepatic portosystemic shunt is helpful in cirrhotic patients with non-cavernomatous PVT in reducing portal pressure and in diminishing the risk of re-thrombosis. In noncirrhotic patients with recent PVT, some authors recommend anticoagulation alone. In chronic thrombotic occlusion of the portal vein, local measures may be implemented if refractory symptoms of portal hypertension are evident.
Asunto(s)
Diagnóstico por Imagen/métodos , Vena Porta/diagnóstico por imagen , Radiología Intervencionista/métodos , Trombosis de la Vena/diagnóstico , Trombosis de la Vena/terapia , Angiografía/métodos , Humanos , Imagen por Resonancia Magnética/métodos , Vena Porta/patología , Portografía/métodos , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía Doppler en Color/métodos , Trombosis de la Vena/diagnóstico por imagenRESUMEN
Myeloproliferative disorder, liver cirrhosis with portal hypertension, deficiency of natural anticoagulant proteins, gene mutation and hepatocellular carcinoma are the most frequent causes of portal vein thrombosis (PVT). Higher accuracy of the diagnostic methods is the reason why today the cause of PVT can be found more frequently. With imaging methods, PVT with or without cavernous transformation can be diagnosed. Fresh thrombus can be undetected in sonography due to the low echogenity but can be recognized in color Doppler sonography, especially with contrast-enhancing agent. Contrast-enhanced 3D MR angiography allows a comparable accuracy in the detection of PVT as digital subtraction angiography. Therapeutical options of PVT consist of mechanical recanalization of the portal vein, local fibrinolysis with or without placement of transjugular intrahepatic portosystemic stent shunt (TIPS), combination of mechanical recanalization and local fibrinolysis, systemic thrombolytic therapy, anticoagulation alone and surgical thrombectomy. Once PVT is found in sonography, Doppler sonography may be performed in order to distinguish benign from malignant thrombus. If further information is needed, MR angiography or contrast enhanced CT is the next step. If these tests are unsatisfactory, digital subtraction angiography should be performed. Until the early nineties, shunt surgery was recommended in patients with PVT who bled despite endoscopic treatment. Today, in symptomatic noncavernomatous PVT, recanalization with local methods is recommended. Additional implantation of TIPS should be performed when the patient is cirrhotic. In recent PVT in non-cirrhotic patients anticoagulation alone is recommended. It is expected that in old PVT anticoagulation can prevent further extension of the thrombus.
Asunto(s)
Terapia Trombolítica/métodos , Procedimientos Quirúrgicos Vasculares/métodos , Trombosis de la Vena/diagnóstico , Trombosis de la Vena/terapia , Animales , Humanos , Vena Porta , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en MedicinaRESUMEN
PURPOSE: To determine the diagnostic value of MRI in preoperative analysis and classification of cartilaginous lesions - especially of the posterior facet - in traumatic calcaneal fractures compared with intraoperative arthroscopy. MATERIALS AND METHODS: Twenty-four consecutive patients with traumatic calcaneal fractures underwent prospective MRI of the subtalar joint surface using T1- and T2-weighted spin echo sequences and fat suppressed 3D gradient echo sequences in semicoronal slice orientation (1.5 T MRI). After randomization, the images were analyzed by two blinded and independent readers experienced in MRI. The results were compared with the intraoperative arthroscopic findings as to location and depth of the defects using the Outerbridge classification. RESULTS: We examined 12 calcaneal fractures of type 2, 8 of type 3 and 4 of type 4 according to the Sanders classification. With respect to principal detection and exact classification, 67 of 96 (69.8 %) of all arthroscopic verified cartilaginous defects were diagnosed correctly by MRI. Disregarding the degree of the defects, 38 of 44 (86.4 %) chondral lesions were detected (sensitivity: 86.4 %, specificity: 86.5 %, diagnostic accuracy: 86.5 %). Considering the chondral lesions of degrees 3 and 4 together, the sensitivity was 86.0 %, the specificity 86.8 %, and the diagnostic accuracy 86.5 % . Assessing these degrees separately, the sensitivity was only 33.3 % for degree 3 and 58.1 % for degree 4, whereas the specificity was definitely higher with 82.1 % for degree 3 and 89.2 % for degree 4. CONCLUSION: The MR detection of cartilaginous defects in calcaneal fractures has a sufficient diagnostic accuracy for planning the surgical intervention and assessing the long-term postsurgical prognosis.
Asunto(s)
Calcáneo/lesiones , Cartílago/patología , Fracturas Óseas/diagnóstico , Imagen por Resonancia Magnética , Adulto , Artroscopía , Interpretación Estadística de Datos , Femenino , Fracturas Óseas/clasificación , Fracturas Óseas/cirugía , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Sensibilidad y EspecificidadRESUMEN
PURPOSE: Evaluation of a correlation between surgical stabilization of fractures of the vertebral spine and postoperative short-term CT findings with special attention to degenerative changes. MATERIALS AND METHODS: The pre- and post-operative CT of 55 patients (43male, 12 female, age: 7 - 73 years, mean = 37.7 years) with traumatic fractures of the vertebral spine who underwent surgical stabilization using an internal fixator were analyzed retrospectively. The interval between surgical intervention and first postoperative CT control did not exceed one week. The interval to the second short-term follow-up CT ranged from 6 up to 24 months (mean: 10.3 +/- 2.7 months). The consensus reading of the short-term CT by two experienced radiologists was compared to the pre- and immediately postoperative CT examinations and with the neurologic findings. Statistical analysis was done using the chi-square- or the Fisher's exact-test. RESULTS: No statistically significant correlation (p > 0.05) was found between the patient's age and the postoperative incidence of osteoporosis, spondylarthrosis, scoliosis, spondylolisthesis or disc protrusion after posttraumatic surgical stabilization using an internal fixator. Also, there was no significant correlation between the fracture's type or location, presence of polytraumatization, the technique of surgical intervention, and the incidence of postoperative degenerative changes in the neighboring segments. The thesis has not been verified (p > 0.05) that polysegment stabilization or prior surgical interventions at the vertebral spine with scar induction are responsible for a higher rate of degeneration. The only risk factor observed for postoperative scoliosis was the burst rotation fracture type C1.3 (AO-classification). CONCLUSIONS: No short-term acceleration of degenerative changes after surgical intervention in vertebral spine fractures was observed. However, due to the short-term interval between surgical intervention and follow-up CT (mean: 10.3 +/- 2.7 months), a final conclusion cannot yet be drawn. A follow-up CT seems to be indicated in patients with increasing complaints during this period. Thus, low grade complications can be diagnosed early.
Asunto(s)
Fijación Interna de Fracturas , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/cirugía , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Distribución de Chi-Cuadrado , Niño , Interpretación Estadística de Datos , Femenino , Estudios de Seguimiento , Humanos , Fijadores Internos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico por imagen , Periodo Posoperatorio , Estudios Retrospectivos , Factores de Riesgo , Escoliosis/diagnóstico por imagen , Espondiloartritis/diagnóstico por imagen , Espondilolistesis/diagnóstico por imagen , Factores de TiempoRESUMEN
PURPOSE: To determine the correlation of the extent of lesions of the supraspinatus tendon in MRI's of the shoulder with surgical or arthroscopic findings using the classification of Snyders and Batemann, respectively. MATERIALS AND METHODS: The preoperative MRI's of 80 patients (age: 16 - 76/47.4 +/- 14.0 years) which were performed due to various complaints of the shoulder were analyzed retrospectively by two experienced and blinded radiologists. We evaluated the incidence and the extent of partial or complete ruptures of the supraspinatus tendon. After MRI, an arthroscopic or open surgical intervention was performed (= gold standard). Various MR-scanners were used with a field strength of 1.0 T (17 cases), or 1.5 T (63 cases) and flexible or inflexible arthro coils. Additionally to plain MRI, 38 of 80 patients underwent contrast enhanced MRI. The MR and the surgical or arthroscopic findings were compared and statistically analyzed. RESULTS: Neglecting the localization and the extent of discontinuity of the supraspinatus tendon, the sensitivity of the 80 MRI's was 0.93, the specificity 0.69, and the accuracy 0.85. The sensitivity increased to 0.96 with constant specificity and an accuracy of 0.83 excluding the lesions with an extent below 1 cm. Compared with non-enhanced examinations, the contrast enhanced MRI revealed higher sensitivity (+ 7 %, 0.89 vs. 0.96), higher specificity (+ 11 %, 0.64 vs. 0.75), and higher accuracy (+ 8 %, 0.81 vs. 0.89) in depicting lesions of the supraspinatus tendon at all. On T 1 -weighted images, the detection of lesions at all and the differentiation between partial and complete ruptures were improved significantly by contrast enhancement, especially in lesions with an extent below 1 cm. Diagnostic failures were seen in examinations without intravenous contrast application, artifacts, extent of the lesion below 1 cm, differentiating between degeneration and partial rupture of the tendon, differentiating between severely degenerated tendons with partial rupture and complete rupture, and covered ruptures. CONCLUSIONS: The performance and consecutively the analysis of the widely used MRI of the shoulder is often not sufficiently reliable in its present routine form. To be able to compete with other imaging modalities such as sonography, standardized MR protocol, contrast enhancement as needed, avoiding the described source of failure, and an exact analysis should be applied.
Asunto(s)
Aumento de la Imagen , Imagen por Resonancia Magnética , Lesiones del Manguito de los Rotadores , Lesiones del Hombro , Traumatismos de los Tendones , Traumatismos de los Tendones/diagnóstico , Adolescente , Adulto , Anciano , Artroscopía , Calcinosis/diagnóstico , Calcinosis/cirugía , Medios de Contraste/administración & dosificación , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Manguito de los Rotadores/patología , Manguito de los Rotadores/cirugía , Rotura/diagnóstico , Rotura/cirugía , Rotura Espontánea/diagnóstico , Rotura Espontánea/cirugía , Sensibilidad y Especificidad , Articulación del Hombro/patología , Articulación del Hombro/cirugía , Traumatismos de los Tendones/cirugía , Tendones/patología , Tendones/cirugíaRESUMEN
In a patient with refractory ascites after right hemihepatectomy TIPS was created between the left hepatic vein and the left portal vein via a transjugular approach. The puncture was guided only by sonography from the epigastrium. Portosystemic pressure gradient was reduced from 28 to 7 mm Hg and ascites disappeared. This case shows that TIPS can be created with technical and clinical success after right hemihepatectomy as left hepatic vein to left portal vein shunt under sonographic guidance.
Asunto(s)
Hepatectomía , Venas Hepáticas , Derivación Portosistémica Intrahepática Transyugular , Venas Hepáticas/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Derivación Portosistémica Intrahepática Transyugular/métodos , Portografía , Punciones , UltrasonografíaRESUMEN
PURPOSE: To evaluate the diagnostic impact of different CT-based measurements to analyze the patellofemoral alignment after arthroscopic reconstruction in patients with patella dislocation. MATERIALS AND METHODS: In 18 patients with dislocation of the patella, CT of the patellofemoral joint was performed after arthroscopic reconstruction. Various methods recommended in the literature were used to analyze the structure and the alignment of the patellofemoral joint with a relaxed quadriceps muscle. Axial CT scans were taken in four different knee flexion angles (15 degrees, 30 degrees, 45 degrees, 60 degrees ). RESULTS: After arthroscopic stabilization in patients with patella dislocation, only the lateral patellofemoral angle (15 degrees and 30 degrees knee flexion) and the congruence angle (15 degrees knee flexion) showed significant differences between the CT-measurements in the normal and the operated group. The differences of the remaining mean values were not significant due to a high standard deviation. With increasing flexion of the knee, the differences between the normal and the dislocation group almost disappeared. Only the lateral patellofemoral angle, the patella tilt and the lateral patella shift revealed differences between the normal and the group with recurrent dislocation in every degree of knee flexion. With increasing knee flexion above 30 degrees and especially at 60 degrees, the majority of the measured values returned to the normal range. CONCLUSIONS: For CT-measurements of the patellofemoral joint after arthroscopic stabilization, the patellofemoral angle and the congruence angle seemed to be most useful. The measurements of the patellofemoral joint should be taken in various degrees of knee flexion.
Asunto(s)
Artroscopía , Desviación Ósea/diagnóstico por imagen , Luxaciones Articulares/cirugía , Articulación de la Rodilla/diagnóstico por imagen , Rótula/lesiones , Complicaciones Posoperatorias/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Femenino , Humanos , Luxaciones Articulares/diagnóstico por imagen , Masculino , Rótula/diagnóstico por imagen , Rótula/cirugía , Recurrencia , Valores de ReferenciaRESUMEN
PURPOSE: To compare the value of B-mode-, plain and contrast enhanced color Doppler ultrasound, CT and MRI with respect to their diagnostic accuracy in palpable enlarged cervical lymph nodes. MATERIAL AND METHODS: Thirty patients (18 - 90 years old) with palpable enlarged lymph nodes of the head and neck underwent B-mode-ultrasound, plain and contrast enhanced color Doppler, CT and MRI (gold standard: histologic analysis in 22 and clinical follow up for at least six months in eight patients). The criteria of malignancy were maximal and minimal lymph node diameter, M/Q-ratio, various morphologic criteria (necrosis, hilus line, internal structure, contour, contrast enhancement), spectral Doppler indices, and vascular architecture in color Doppler. RESULTS: The highest sensitivity (= 1.00, specificity = 0.07 - 0.15) was obtained measuring the lymph node diameter independent on the used imaging modality (ultrasound, CT, MRI), the highest specificity (= 1.00, sensitivity = 0.71) analyzing the vascularity of the lymph node by plain color Doppler. The highest diagnostic (= 0.93) accuracy was delivered by contrast enhanced color Doppler analysis of the vascularity. Sensitivity (= 0.94) and specificity (= 0.92) of this imaging modality were only slightly inferior to the top values. Fisher's exact test revealed significant values in differentiating malignant from benign lymph nodes for B-mode- and MR-analysis of the M/Q-ratio (p < 0001/p < 0.05), B-mode morphology (p < 0.00005), plain and contrast enhanced color Doppler analysis of the vascularity (p < 0.0001/p < 0.000005), MR-morphology (p < 0.0001), and CT-morphology (p < 0.005). CONCLUSION: CT is inferior to MRI, B-mode-ultrasound and contrast-enhanced color Doppler in the differential diagnosis of selectively analyzed, palpably enlarged cervical lymph nodes using the criteria of our study. The analysis of the MR-morphology revealed a slightly inferior diagnostic accuracy to B-mode morphology and color Doppler analysis of the vascularity.
Asunto(s)
Neoplasias de Cabeza y Cuello/secundario , Metástasis Linfática/diagnóstico , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X , Ultrasonografía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Femenino , Neoplasias de Cabeza y Cuello/diagnóstico , Humanos , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Ultrasonografía Doppler en ColorRESUMEN
PURPOSE: To compare the ability of standard power Doppler and color harmonic imaging for visualising breast tumor vascularity using ultrasound probes of various frequencies, and to evaluate the influence on diagnostic accuracy using ultrasound contrast agent. MATERIALS AND METHODS: Twenty patients (x = 43.6 +/- 11.7 years) with suspected malignancy of the breast underwent power Doppler to evaluate vascularity and to offer a differential diagnosis of the lesion. Two criteria were used for differential diagnosis: The quantitative extent of vascularity ("percentage vessel area", PVA) and the qualitative assessment of vascular architecture. The following power Doppler modes were compared in every patient: Plain and enhanced (Levovist(R)) 9 MHz and 12 MHz standard power mode and enhanced 9 MHz color harmonic imaging-(CHI). RESULTS: The PVA increased from a mean of 2.2 +/- 2.9 % (9 MHz standard plain) via 4.8 +/- 4.1 % (12 MHz standard plain), 9.7 +/- 15.3 % (9 MHz standard enhanced), 17.4 +/- 20.0 % (9 MHz CHI enhanced) up to 19.4 +/- 14.8 % (12 MHz standard enhanced). The perceptibility of the vascular structure was best using the enhanced 12 MHz standard power mode, immediately followed by the enhanced 9 MHz CHI mode. The improved detection of vascular signal did not translate into improved diagnostic accuracy. The highest diagnostic accuracy (95 %) was obtained using the enhanced 9 MHz CHI mode (criterion "PVA") and the enhanced 9 MHz standard power mode (criterion "vascular structure"), whereas the 12 MHz probes delivered insufficient diagnostic accuracy and very low specificity. CONCLUSION: Best quantitative and qualitative visualisation of the tumor vascularity was achieved using the enhanced 12 MHz standard power mode. Nevertheless, the highest diagnostic accuracy was obtained using enhanced 9 MHz standard power Doppler and enhanced 9 MHz color harmonic imaging. The visualisation of tumor vascularity and, partially, the diagnostic accuracy are improved significantly by color harmonic imaging without changing the probe frequently.
Asunto(s)
Neoplasias de la Mama/irrigación sanguínea , Aumento de la Imagen , Neovascularización Patológica/diagnóstico por imagen , Ultrasonografía Doppler en Color , Ultrasonografía Mamaria , Adulto , Anciano , Neoplasias de la Mama/diagnóstico por imagen , Medios de Contraste , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polisacáridos , Sensibilidad y EspecificidadRESUMEN
UNLABELLED: Radiological-guided liver-port implantation: Evaluation, technical approach, interventional procedure and follow up. PURPOSE: Description of evaluation, technical approach, interventional procedure and follow up of radiological-guided liver-port implantation. METHOD: Percutaneous implantation of a liver-port system was performed in twelve patients through a transfemoral approach and in one patient via the superficial epigastric artery after surgical exploration. In four patients we used port systems which are accessible via ventral puncture. Strecker-port systems were implanted in the remaining nine patients. RESULTS: The liver-port implantation was technically successful in all cases. No dislocation of the distal catheter tip, no thrombosis of the hepatic or splenic artery, no leakage near connections of the catheters or connections of catheter and port system and no thrombosis of the femoral arteries were observed. Correction of a kink in the catheter was performed in one patient. Another patient showed prolonged healing of the subcutaneous pocket. CONCLUSIONS: Interventional liver-port implantation is a safe procedure and leads to good clinical results. From the view of the radiologist the Strecker-system shows a good performance. The approach via the superficial epigastric artery demands excellent interdisciplinary cooperation.
Asunto(s)
Antineoplásicos/administración & dosificación , Carcinoma Hepatocelular/tratamiento farmacológico , Catéteres de Permanencia , Neoplasias Colorrectales/tratamiento farmacológico , Infusiones Intraarteriales , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Angiografía por Resonancia Magnética , Angiografía , Carcinoma Hepatocelular/irrigación sanguínea , Cateterismo Periférico/instrumentación , Neoplasias Colorrectales/irrigación sanguínea , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Neoplasias Hepáticas/irrigación sanguínea , MasculinoRESUMEN
A major concern about combined pulmonary CT angiography (PCTA) and CT venography (CTV) refers to the additional radiation exposure to the patient. The purpose of this paper is to analyze the organ dose, the effective dose, and the gonadal dose of combined PCTA and CTV. Effective dose and gonadal dose in PCTA and CTV were calculated. Also measured was the organ doses with thermoluminescence dosimeters in six patients who underwent combined PCTA/CTV. The risk from the effective dose and gonadal dose in combined PCTA/CTV is low. Nevertheless, additional CTV increases the gonadal dose by a significant factor and use of this procedure should be limited in younger patients.
Asunto(s)
Angiografía/métodos , Flebografía , Embolia Pulmonar/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Trombosis de la Vena/diagnóstico por imagen , Humanos , Monitoreo de Radiación/métodos , Efectividad Biológica Relativa , RiesgoRESUMEN
The purpose of this study was to evaluate the reliability of unenhanced and enhanced power Doppler sonography in visualization of intratumoral angioneogenesis. Thirty-seven malignant melanomas, which had been implanted intra- or subcutaneously in 22 mice, were examined. Various B-mode criteria, power Doppler criteria and spectral Doppler parameters were evaluated before and after IV-application of the d-galactose-based contrast agent Levovist. After sonographic examination, all tumors were analyzed histologically with semiquantitative grading of tumoral vascularization. Unenhanced, in 70% of the tumors, no intratumoral vessels were visible using power Doppler, but only in 11% of the intracutaneous and in 0% of the subcutaneous after injection of the contrast agent. The enhanced mode was definitely superior to unenhanced Doppler in showing the intratumoral vascularity. The intratumoral vascular structure could be sufficiently analyzed in 30% of all tumors by unenhanced Doppler, but in 92% enhanced. The mean percentage vessel area increased about 433% after application of Levovist (intracutaneous: 485%, subcutaneous: 280%). Despite the missing direct correlation between the sonographically and histologically determined grade of tumor vascularization (Pearson's correlation unenhanced 0,356, p <.05/enhanced 0.395, p <.05), the correlation between the percentage vessel area and the histologic grade of vascularization was improved after application of the contrast agent (Pearson's correlation unenhanced 0.347, p <.05/enhanced 0.686, p <.01). We did not find a significant direct correlation between histologically and sonographically determined degree of vascularization. However, the correlation was improved using a d-galactose-based signal-enhancing agent in power Doppler sonography.
Asunto(s)
Medios de Contraste , Melanoma Experimental/irrigación sanguínea , Melanoma Experimental/diagnóstico por imagen , Neovascularización Patológica/diagnóstico por imagen , Polisacáridos , Neoplasias Cutáneas/irrigación sanguínea , Neoplasias Cutáneas/diagnóstico por imagen , Ultrasonografía Doppler , Animales , Procesamiento de Imagen Asistido por Computador , Masculino , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C57BL , Necrosis , Neoplasias Cutáneas/patologíaRESUMEN
PURPOSE: Confirmation of a new technique for evaluating bone mineral density (BMD). Colored coded imaging of topographical distribution of bone mineral density in the spongy substance. METHOD: For 20 patients, dental CT examinations of the mandible were made in axial slices. Spongy substance and cortical bone pixels were automatically segmented at foramina mentalia level by means of threshold fixation. The segments were separated in areas relevant to implantology. For each region, BMD was measured by means of quantitative computed tomography (QCT). Spongiose substance of 20 mandibles was segmented by using three threshold intervals to image topographical BMD distribution. RESULTS: Cortical bone and spongy substance could be automatically segmented for 20 mandibles. BMD could be measured in each region. The results were comparable with those of other techniques. Three threshold intervals were segmented for 20 mandibles in the spongy substance to depict topographical BMD distribution. CONCLUSIONS: Areas of low BMD can be detected by imaging topographical BMD distribution. This way, subjective rating by the examiner is eliminated.
Asunto(s)
Densidad Ósea/fisiología , Implantación Dental Endoósea , Procesamiento de Imagen Asistido por Computador , Mandíbula/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Sensibilidad y EspecificidadRESUMEN
PURPOSE: Evaluation of colour Doppler criteria to differentiate between malignant and benign skin tumours on the basis of the degree of vascularization. MATERIAL AND METHODS: The B-mode sonomorphology and the degree of vascularization in colour Doppler of 81 clinically potentially malignant tumours of cutaneous and subcutaneous structures were analyzed and quantified by number of intratumoral vessels per sonographic slice and percentage vessel area. RESULTS: Of all criteria employed, counting the intratumoral vessels visible on one ultrasound slice after application of a signal-enhancing agent led to highest sensitivity (94%) of all used criteria but the specificity was poor (64%). The highest specificity (88%) and greatest diagnostic accuracy (86%) discriminating benign and malignant lesions were found using the criterion "percentage vessel area >5.0%" after all inflamed lesions had been excluded on the basis of clinical criteria. Plain colour Doppler increased the specificity up to 97%, although the sensitivity decreased simultaneously to max. 75%. Analysis of the B-mode morphology and spectral Doppler parameter of intratumoral vessels did not contribute to the differential diagnosis. CONCLUSION: Signal-enhanced colour Doppler sonography is a valuable tool in the pretherapeutic assessment of cutaneous lesions. This method may be relevant for therapy and prognosis.
Asunto(s)
Medios de Contraste , Galactosa , Polisacáridos , Neoplasias Cutáneas/irrigación sanguínea , Neoplasias Cutáneas/diagnóstico por imagen , Ultrasonografía Doppler en Color , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Sensibilidad y EspecificidadRESUMEN
Symptomatic portal vein stenosis is an uncommon complication after liver transplantation. Portal vein angioplasty has been successfully established for treatment of portal vein stenosis using mesenteric or percutaneous, transhepatic approaches. We herein report on a patient who suffered from variceal bleeding due to portal hypertension 3 months after liver transplantation. After successful endoscopic sclerotherapy, an extrahepatic portal vein stenosis was diagnosed, and portal vein angioplasty was considered as primary therapeutic option. Instead of mesenteric or percutaneous, transhepatic approaches, we adopted a transjugular, intrahepatic access to introduce a 14-mm balloon catheter into the portal vein. Using this technique, angioplasty was successfully performed. After intervention, no further episodes of variceal bleeding occurred. We favour the transjugular, intrahepatic technique for portal vein angioplasty because it does not require general anesthesia, in contrast to the mesenteric approach, and it reduces the risk of intra-abdominal bleeding, compared to the percutaneous, transhepatic approach.
Asunto(s)
Angioplastia/métodos , Trasplante de Hígado/efectos adversos , Vena Porta/cirugía , Constricción Patológica , Várices Esofágicas y Gástricas/etiología , Várices Esofágicas y Gástricas/cirugía , Humanos , Hipertensión Portal/etiología , Hipertensión Portal/cirugía , Trasplante de Hígado/patología , Masculino , Persona de Mediana Edad , Vena Porta/patologíaRESUMEN
PURPOSE: To investigate the radiation dose for conventional computed tomography (CT) and spiral CT during different CT examinations at various hospitals and practices. MATERIALS AND METHODS: CT dose index with an active length of 15 cm was measured in 16 different types of CT scanners by using ionization chamber dosimetry. Twenty-six holders (one who has legal responsibility under national law for a radiologic installation) operating a total of seven conventional and 20 spiral CT scanners were asked for their standard parameters for various CT examinations. Weighted CT dose index and dose-length product were determined for each examination. RESULTS: For most examinations, the tube current time product was significantly higher for conventional CT than for spiral CT (.002