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1.
Eur Arch Otorhinolaryngol ; 279(5): 2583-2589, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34495350

RESUMEN

PURPOSE: We aimed to evaluate the power of 18F-fluorocholine (FCH) positron emission tomography/magnetic resonance (PET/MR) imaging in unlocalized primary hyperparathyroidism. METHODS: Thirty-four patients were included. In 17/34 patients, PET/MR was performed immediately after a negative 18F-FCH PET/CT. Sensitivity, specificity, positive and negative predictive values were calculated for MR only (blinded to PET data) and PET only (blinded to MR data) findings. RESULTS: 18F-FCH PET/MR was positive in 26/34 (76%) patients. PET/MR was also positive in 12/17 (71%) patients with a negative PET/CT. Among 11/34 (32%) patients where 18F-FCH PET-only and MR-only results were discordant, MR was false positive in 7/11 patients (3/7 of the lesions were not 18F-FCH avid and in 4/7 of them PET and MRI pointed different locations. Postoperative histopathology revealed that 18F-FCH-positive ones were true positives). Sensitivity, specificity, PPV, NPV and accuracy of neck MR evaluated blinded to PET data were 80%, 50%, 70%, 64% and 68%, respectively, and all were calculated as 100% for PET/MR. CONCLUSION: 18F-FCH PET/MR is very effective in preoperative localization of parathyroid adenomas even if 18F-FCH PET/CT is negative. Neck MR alone is insufficient in detecting parathyroid adenomas but PET/MR combination helps in precise localisation.


Asunto(s)
Hiperparatiroidismo Primario , Neoplasias de las Paratiroides , Colina/análogos & derivados , Humanos , Hiperparatiroidismo Primario/diagnóstico por imagen , Hiperparatiroidismo Primario/cirugía , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Tomografía de Emisión de Positrones/métodos
2.
Can Assoc Radiol J ; 70(4): 457-465, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31582328

RESUMEN

PURPOSE: The aim of this study is to evaluate the diagnostic contribution of diffusion-weighted magnetic resonance imaging (MRI) and computed tomography (CT) to distinguish extramural venous invasion (EMVI) in rectal adenocarcinoma. MATERIALS AND METHODS: Fifty-eight patients who had been diagnosed with rectal adenocarcinoma (30 patients with EMVI and 28 patients without EMVI) were enrolled in the study. Apparent diffusion coefficient (ADC) values of the tumour and the EMVI (+) vein, the lengths of the tumours were measured on MRI. The diameters of the superior rectal vein (SRV)-inferior mesenteric vein (IMV) and distant metastatic spread were evaluated on CT. The ability of these findings to detect EMVI was assessed using receiver operating characteristic (ROC) analysis. Pathology was accepted as the reference test for EMVI. RESULTS: Mean diameters of the SRV (4.9 ± 0.9 mm vs 3.7 ± 0.8 mm) and IMV (6.9 ± 0.8 mm vs 5.4 ± 0.9 mm) were significantly larger (P < .001) and tumour ADC values were significantly lower (0.926 ± 0.281 × 10-3 mm2/s vs 1.026 ± 0.246 × 10-3 mm2/s; P = .032) in EMVI (+) patients. Diameters of 3.95 mm for the SRV (area under the curve [AUC] ± standard error [SE]: 0.851 ± 0.051, P < .001, sensitivity: 93.3%, specificity: 67.9%) and 5.95 mm for the IMV (AUC ± SE: 0.893 ± 0.040, P < .001, sensitivity: 93.3%, specificity: 71.4%) and an ADC value of 0.929 × 10-3 mm2/s (AUC ± SE: 0.664 ± 0.072, P = .032 sensitivity: 76.7%, specificity: 57.1%) were found to be cutoff values, determined by ROC analysis, for detection of EMVI. Distant metastases were significantly more prevalent in EMVI (+) patients (P < .001). CONCLUSION: The measurement of ADC values and SRV-IMV diameters seems to have contribution for diagnosis of EMVI in rectal adenocarcinoma. EMVI (+) patients appear to have higher risks of distant metastases at diagnosis.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/patología , Imagen de Difusión por Resonancia Magnética/métodos , Invasividad Neoplásica/diagnóstico por imagen , Invasividad Neoplásica/patología , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/patología , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recto/irrigación sanguínea , Recto/diagnóstico por imagen , Estudios Retrospectivos
3.
Pol J Radiol ; 84: e470-e477, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32082442

RESUMEN

PURPOSE: We aimed to evaluate whether lumbar vertebrae can be correctly numbered using auxiliary parameters. MATERIAL AND METHODS: Vertebra corpus shape, O'Driscoll classification, lumbosacral axis angle, last two square vertebra dimensions, orifice of right renal artery (RRA), orifice of celiac truncus (CT), orifice of superior mesenteric artery (SMA), vena cava inferior confluence (CVC), abdominal aorta bifurcation (AB), and iliolumbar ligament were evaluated in this study. RESULTS: Lumbosacral transitional vertebrae (LSTV) were observed in 13 (9%) patients. The most common locations of the paraspinal parameters were: RRA: L1 vertebrae (45%), SMA: L1 vertebrae (66%), CT: T12 vertebrae (46%), AB: L4 vertebrae (63%), and CVC: L4 vertebrae (52%). CONCLUSIONS: According to the results of our study, no single parameter in the magnetic resonance imaging can accurately indicate the number of vertebrae without counting the levels. As a result, we believe that these parameters may be suspicious in terms of the presence of LSTV rather than the correct level.

4.
AJR Am J Roentgenol ; 211(4): 767-775, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30085839

RESUMEN

OBJECTIVE: The purposes of this study were to discern imaging findings that distinguish Behçet disease from small-bowel Crohn disease, to find initial performance estimates for these findings, and to evaluate the diagnostic value of MR enterography (MRE) for detecting intestinal Behçet disease. MATERIALS AND METHODS: The MRE examinations of 30 consecutively registered patients with established intestinal Behçet disease were reviewed by two blinded readers. The frequencies of MRE findings were compared with those obtained for 30 control subjects with small-bowel Crohn disease who were matched for sex and age. The performance estimates were generated with ileocolonoscopic and histopathologic findings as the reference standard. RESULTS: Polypoid pattern and homogeneous mural enhancement were the findings seen more frequently in Behçet disease (p = 0.000) than in Crohn disease (p = 0.003). Stricture formation, long-segment disease, and involvement of more proximal ileal segments favored small-bowel Crohn disease. The ROC AUCs for polypoid pattern and homogeneous mural enhancement in the detection of intestinal Behçet disease were 0.806 and 0.779. The accuracy of MRE was 70.00% (95% CI, 50.60-85.27%); sensitivity, 57.14% (95% CI, 34.02-78.18%), and specificity, 100% (95% CI, 66.37-100%). CONCLUSION: MRE has potential for use as a radiation-free alternative for clarifying the cause of nonspecific gastrointestinal symptoms in patients with known Behçet disease. However, additional studies are needed to determine the actual value of MRE in patients with Behçet disease and to validate the clinical usefulness of the technique in the detection of unknown intestinal Behçet disease.


Asunto(s)
Síndrome de Behçet/diagnóstico por imagen , Enfermedades Intestinales/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Adulto , Síndrome de Behçet/patología , Estudios de Casos y Controles , Medios de Contraste , Enfermedad de Crohn/diagnóstico por imagen , Diagnóstico Diferencial , Femenino , Humanos , Enfermedades Intestinales/patología , Intestino Delgado , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
5.
Childs Nerv Syst ; 34(5): 933-938, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29392421

RESUMEN

PURPOSE: We aimed to determine whether varying the magnetic field during magnetic resonance imaging would affect the development of chicken embryos and neural tube defects. METHODS: Following incubation for 24 h, we exposed chicken embryos to varying magnetic fields for 10 min to assess the impact on development. Three magnetic resonance imaging devices were used, and the eggs were divided into four groups: group 1 is exposed to 1 T, group 2 is exposed to 1.5 T, group 3 is exposed to 3 T, and group 4, control group, was not exposed to magnetic field. After MRI exposure, all embryos were again put inside incubator to complete 48 h. "The new technique" was used to open eggs, a stereomicroscope was used for the examination of magnified external morphology, and each embryo was examined according to the Hamburger and Hamilton chicken embryo stages. Embryos who had delayed stages of development are considered growth retarded. Growth retardation criteria do not include small for stage. RESULTS: Compared with embryos not exposed to a magnetic field, there was a statistically significant increase in the incidence of neural tube closure defects and growth retardation in the embryos exposed to magnetic fields (p < 0.05). However, although the incidence of neural tube closure defects was expected to increase as exposure (tesla level) increased, we found a higher rate of defects in the 1.5-T group compared with the 3-T group. By contrast, the highest incidence of growth retardation was in the 3-T group, which was consistent with our expectation that growth retardation would be more likely as tesla level increased. CONCLUSIONS: We therefore conclude that the use of magnetic resonance imaging as a diagnostic tool can result in midline closure defects and growth retardation in chicken embryos. We hypothesize that this may also be true for human embryos exposed to MRI. If a pregnant individual is to take an MRI scan, as for lumbar disc disease or any other any other reason, our results indicate that consideration should be given to an avoidance of MRI during pregnancy.


Asunto(s)
Embrión de Pollo/efectos de la radiación , Desarrollo Embrionario/efectos de la radiación , Campos Magnéticos/efectos adversos , Imagen por Resonancia Magnética/efectos adversos , Defectos del Tubo Neural/etiología , Tubo Neural/efectos de la radiación , Animales , Modelos Animales de Enfermedad , Relación Dosis-Respuesta en la Radiación , Tubo Neural/diagnóstico por imagen , Tubo Neural/embriología , Defectos del Tubo Neural/diagnóstico por imagen
6.
Rheumatol Int ; 35(2): 367-70, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24957970

RESUMEN

Behçet's disease (BD) is a chronic multi-system disorder commonly seen in Mediterranean, middle east and far eastern populations. In this report, we describe a case of a 55-year-old male with Behçet's disease who presented with a low back pain and sciatica. Imaging studies showed that he had a destruction of the third lumbar vertebra because of abdominal aortic aneurysm-related Behçet's disease. Aortic aneurysms with vertebral body erosion have been rarely reported, but this vascular complication is a life-threatening clinical picture. Therefore, among the causes of chronic lumbar pain in a BD patient, abdominal aortic aneurysm should be remembered.


Asunto(s)
Aneurisma de la Aorta Abdominal/diagnóstico , Síndrome de Behçet/complicaciones , Vena Ilíaca/patología , Dolor de la Región Lumbar/diagnóstico , Vértebras Lumbares/lesiones , Osteólisis/diagnóstico , Vena Cava Inferior/patología , Trombosis de la Vena/diagnóstico , Angiografía , Aneurisma de la Aorta Abdominal/complicaciones , Humanos , Dolor de la Región Lumbar/etiología , Vértebras Lumbares/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Osteólisis/etiología , Tomógrafos Computarizados por Rayos X , Trombosis de la Vena/etiología
7.
AJR Am J Roentgenol ; 202(1): 74-82, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24370131

RESUMEN

OBJECTIVE: The purpose of this article is to determine the added diagnostic value of T1-weighted gradient-echo in-phase images obtained during MRCP in the detection and differentiation of hepatolithiasis and intrahepatic pneumobilia. MATERIALS AND METHODS: Intrahepatic bile ducts in 47 patients were scored in terms of their possibility of containing biliary stone and air. MRI was performed with a 1-T system for 32 patients and with a 3-T system for 15 patients. Two radiologists independently reviewed two sets of MRI scans: set 1 included T2-weighted MRCP images, and set 2 included T2-weighted MRCP images plus T1-weighted gradient-echo in-phase images. The diagnostic performances of set 1 and set 2 in the evaluation of the bile ducts containing air or stone and bile ducts containing neither of them were analyzed using the area under the receiver operating characteristic curve (AUC) for clustered data. The sensitivities and specificities of both image sets to detect intrahepatic stone or air were also calculated and compared. RESULTS: For the diagnosis of hepatolithiasis, the AUC obtained from set 2 (0.983) was significantly higher than that obtained from set 1 (0.879; p = 0.037). For the diagnosis of pneumobilia, the AUC obtained from set 2 (0.965) was also significantly higher than that of set 1 (0.765; p = 0.002). With use of percutaneous transhepatic cholangiography, ERCP, and CT as the reference standards, the sensitivity of set 2 (97.1%; 95% CI, 91.1-100%) was significantly higher than that of set 1 (74.3%; 95% CI, 56.7-91.9%) in detecting intrahepatic stones (p = 0.011). For the detection of pneumobilia, the sensitivity of set 2 (98.5%; 95% CI, 95.4-100%) was also significantly higher than that of set 1 (70.8%; 95% CI, 57.7-83.3%; p = 0.000). CONCLUSION: The addition of T1-weighted gradient-echo in-phase images to standard MRCP sequences improves the detection and differentiation of hepatolithiasis and intrahepatic pneumobilia.


Asunto(s)
Conductos Biliares Intrahepáticos , Enfermedades de las Vías Biliares/diagnóstico , Pancreatocolangiografía por Resonancia Magnética/métodos , Cálculos Biliares/diagnóstico , Gases , Adulto , Anciano , Enfermedades de las Vías Biliares/etiología , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad
8.
J Stroke Cerebrovasc Dis ; 21(8): 907.e9-12, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21917479

RESUMEN

We present a case of transient ischemic attack (TIA) as an extremely rare presentation of cerebral vein thrombosis. A 41-year-old man presented with a headache and episodes of hypoesthesia on his left side lasting approximately 30 minutes. Several vascular risk factors were remarkable in his medical history. The neurologic examination was normal. TIA of arterial origin was excluded by detailed investigations. Magnetic resonance imaging revealed acute thrombosis of the right superficial middle cerebral vein and the vein of Trolard. TIA-like episodes stopped with anticoagulation. Head trauma a few days earlier was the most likely mechanism of venous thrombosis. We suggest that the patients with TIA and headache should be carefully investigated in terms of cerebral venous thrombosis.


Asunto(s)
Trombosis Intracraneal/diagnóstico , Ataque Isquémico Transitorio/etiología , Trombosis de la Vena/complicaciones , Administración Oral , Adulto , Anticoagulantes/administración & dosificación , Cefalea/etiología , Humanos , Hipoestesia/etiología , Trombosis Intracraneal/complicaciones , Trombosis Intracraneal/tratamiento farmacológico , Ataque Isquémico Transitorio/diagnóstico , Ataque Isquémico Transitorio/tratamiento farmacológico , Imagen por Resonancia Magnética , Masculino , Flebografía/métodos , Valor Predictivo de las Pruebas , Factores de Riesgo , Trombosis de la Vena/diagnóstico , Trombosis de la Vena/tratamiento farmacológico
9.
Diagn Interv Radiol ; 28(4): 286-293, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35950273

RESUMEN

PURPOSE We aimed to evaluate the spectrum of magnetic resonance cholangiopancreatography (MRCP) findings in patients with ectopic opening of the common bile duct (CBD) into the duodenal bulb and to determine the effectiveness of the MRCP technique in diagnosis. METHODS Morphologic and morphometric MRCP/MRI features in 16 patients and 36 controls were retrospectively analyzed by 2 radiologists. The frequency of MRCP findings was determined. The significance of the difference between the MRCP observations in patients and controls was evaluated statistically and the diagnostic effectiveness of MRCP was investigated. RESULTS Hook-shaped ending of CBD and bulbar deformity were the most frequent morphologic findings seen on MRCP in the ectopic bulbar opening. Mean pylorus-papilla distance and mean CBD length were significantly shorter and the median diameter of CBD was significantly larger than the control group (patients: 28.6 ± 15.3 mm, 33.7 ± 12.8 mm, 8.6 (2-16) mm; controls: 66.7 ± 11.7 mm, 50.3 ± 14.4 mm, 3.2 (1.5-10) mm, P < .001, respectively). Receiver operating curve analysis showed sensitivity and specificity of MRCP in the diagnosis to be 87.5% and 100%, respectively, if any 3 of the 4 signs (hook-shaped ending of CBD, bulbar deformity, large, and short CBD) were present in a patient whose pylorus-papilla distance was <50 mm. CONCLUSION At MRCP, the presence of short and large CBD with a hook-shaped ending in the deformed duodenal bulb may support the diagnosis of ectopic biliary drainage.


Asunto(s)
Colangiopancreatografia Retrógrada Endoscópica , Pancreatocolangiografía por Resonancia Magnética , Colangiopancreatografia Retrógrada Endoscópica/métodos , Pancreatocolangiografía por Resonancia Magnética/métodos , Conducto Colédoco/diagnóstico por imagen , Duodeno/diagnóstico por imagen , Humanos , Estudios Retrospectivos
10.
Diagn Interv Radiol ; 27(1): 7-14, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33290237

RESUMEN

PURPOSE: Nonalcoholic fatty liver disease (NAFLD) can progress to liver cirrhosis and is predicted to become the most frequent indication for liver transplantation in the near future. Noninvasive assessment of NAFLD is important for diagnosis and patient management. This study aims to prospectively determine the liver stiffness and T1 and T2 values in patients with NAFLD and to compare the diagnostic performance of magnetic resonance elastography (MRE) and mapping techniques in relation to the proton density fat fraction (PDFF). METHODS: Eighty-three patients with NAFLD and 26 participants with normal livers were imaged with a 1.5 T scanner. PDFF measurements obtained from the multiecho Dixon technique were used to quantify the liver fat. MRE, native T1 mapping (modified Look-Locker inversion recovery [MOLLI] schemes 5(3)3, 3(3)3(3)5, and 3(2)3(2)5 and the B1-corrected variable flip angle [VFA] method), and T2 mapping values were correlated with PDFF. The diagnostic performance of MRE and the mapping techniques were analyzed and compared. RESULTS: T1 values measured with the MOLLI schemes and the B1-corrected VFA (P < 0.001), and the stiffness values from MRE (P = 0.047) were significantly higher in the NAFLD group. No significant difference was found between the groups in terms of T2 values (P = 0.127). In differentiation of the NAFLD and control groups, the B1-corrected VFA technique had slightly higher accuracy and area under the curve (AUC) than the MOLLI schemes. In the NAFLD group, there was a good correlation between the PDFF, MOLLI 3(3)3(3)5 and 3(2)3(2)5, and VFA T1 measurements (r=0.732; r=0.735; r=0.716, P < 0.001, respectively). CONCLUSION: Liver T1 mapping techniques have the potential to distinguish steatotic from nonsteatotic livers, and T1 values seem to have a strong correlation with the liver fat content.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Enfermedad del Hígado Graso no Alcohólico , Humanos , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Protones
11.
Eur J Radiol ; 110: 212-218, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30599862

RESUMEN

OBJECTIVE: To reveal the MR enterography (MRE) findings that distinguish backwash ileitis (BWI) from terminal ileitis due to Crohn's disease (CD) and to determine the usability of barium studies manifestations (ileocecal valve (ICV) gaping, terminal ileum dilatation) in MRE for the diagnosis of BWI in ulcerative colitis (UC) patients by pointing at the diagnostic performance of these imaging findings. SUBJECTS-METHODS: The study population consisted of patients who were diagnosed as ulcerative colitis (UC), and underwent 1.5 T MRI between August 2011 and November 2017 to rule out small bowel involvement. The matched controls were comprised of Crohn's patients examined at the same period. Ileocolonoscopic/ histopathologic findings were accepted as reference standard. Mural/extramural changes in bowel segments, ileocecal valve (ICV) gaping, terminal ileum dilatation, restricted diffusion and anatomical extent of involvement were evaluated. In UC patients, the association between ICV gaping and terminal ileum dilatation and BWI was assessed by χ2 test. The diagnostic accuracy of these two findings in BWI was determined. RESULTS: Sixty patients were included in the study (30 UC; 30 CD; mean age, 43 years in both groups). Ileocecal valve gaping and terminal ileum dilatation were significantly more frequent among BWI patients (p < 0.001) in UC. Patients with BWI showed a higher rate of pancolitis (88.9%). Median terminal ileum wall thickness was found to be significantly greater in patients with CD (p < 0.001). CONCLUSION: In patients with definite diagnosis of UC, ileocecal valve gaping and terminal ileum dilatation suggest the development of BWI. However, these findings cannot be use to differentiate cause of terminal ileitis in patients with unconfirmed diagnosis and do not give reliable information about the causative factor of ileitis.


Asunto(s)
Colitis Ulcerosa/diagnóstico por imagen , Enfermedad de Crohn/diagnóstico por imagen , Ileítis/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Anciano , Colitis Ulcerosa/complicaciones , Enfermedad de Crohn/patología , Diagnóstico Diferencial , Femenino , Humanos , Ileítis/complicaciones , Ileítis/patología , Íleon/diagnóstico por imagen , Íleon/patología , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Adulto Joven
12.
Diagn Interv Radiol ; 14(1): 26-8, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18306141

RESUMEN

Isolated internal iliac aneurysms are rare. Unless rupture occurs, they usually remain asymptomatic. In this paper, a patient with a ruptured internal iliac aneurysm that resulted in chronic stage hematoma causing lumbosacral plexopathy and erosion of the pelvic bony structures is presented, along with magnetic resonance imaging (MRI) and computed tomography (CT) findings. To expedite the diagnosis of extraspinal radicular pain, one should pay attention to the extraspinal structures involved in lumbar CT or MRI examinations. If necessary, further investigation can be made with pelvic CT or MRI.


Asunto(s)
Aneurisma Roto/diagnóstico , Aneurisma Ilíaco/diagnóstico , Dolor de la Región Lumbar/etiología , Plexo Lumbosacro , Enfermedades del Sistema Nervioso Periférico/etiología , Aneurisma Roto/complicaciones , Aneurisma Roto/diagnóstico por imagen , Diagnóstico Diferencial , Humanos , Aneurisma Ilíaco/complicaciones , Aneurisma Ilíaco/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
13.
Am J Orthod Dentofacial Orthop ; 133(6): 823-9, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18538245

RESUMEN

INTRODUCTION: In this prospective clinical study, we used bilateral temporomandibular joint (TMJ) magnetic resonance images (MRIs) to investigate the condylar response to rapid maxillary expansion (RME). METHODS: Bilaterial MRIs of the TMJs of 18 subjects (11 girls, 7 boys; mean age, 12.54 years; range, 9.75-14.8 years) were assessed. All subjects had unilateral or bilateral posterior crossbites involving 3 or more posterior teeth. There was no control group because of the short observation period. The MRI protocol included closed-mouth parasagittal proton density weighted spin echo and fat-suppressed short T1 inversion recovery sequences. The MRIs were taken before treatment (Tx 1), and at 6 weeks (Tx 2) and at 18 weeks (Tx 3) after treatment. Alterations in the signal intensities of the TMJ region were examined visually by a radiologist who was blinded to the subjects' characteristics. RESULTS: Increased signal intensities appeared as bright areas on the MRIs, indicating red bone marrow edema that is a sign of condylar remodeling. There were no bright areas in the condylar regions at Tx 2 in the 36 TMJs. Bright areas at the condylar region were observed both in proton density and fat-suppressed spin echo sequences at Tx 3 in 32 TMJs. Twenty-two TMJs had bright areas localized at the condylar head, and 10 TMJs had bright areas that extended through both the condyle and the mandibular ramus. No bright areas were seen at Tx 2 or Tx 3 for 4 TMJs. CONCLUSIONS: A condylar response to RME was observed in 32 TMJs at 18 weeks after expansion. Both the extensive orthopedic and the functional occlusal forces associated with RME have roles in condylar and ramal responses.


Asunto(s)
Maloclusión/complicaciones , Cóndilo Mandibular/patología , Técnica de Expansión Palatina/efectos adversos , Trastornos de la Articulación Temporomandibular/etiología , Articulación Temporomandibular/patología , Adolescente , Remodelación Ósea , Niño , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Maloclusión/terapia , Estudios Prospectivos , Trastornos de la Articulación Temporomandibular/patología
14.
Diagn Interv Radiol ; 24(6): 328-335, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30272563

RESUMEN

Magnetic resonance elastography (MRE) is a constantly advancing technique for assessment of stiffness of tissues with newer technology and sequences. It is being increasingly used for the assessment of liver fibrosis. In this article, we discuss the advantages of MRE over biopsy and noninvasive methods such as US elastography in the assessment of liver fibrosis. Image acquisition and interpretation of liver MRE is also discussed.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Cirrosis Hepática/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Hígado/diagnóstico por imagen
15.
Br J Radiol ; 91(1082): 20170581, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29120661

RESUMEN

OBJECTIVE: To determine the diagnostic value of 3 Tesla MR imaging in detection of mucosal (Tis), submucosal (T1) and muscularis propria (T2) invasion in patients with early rectal cancer. METHODS: A total of 50 consecutive patients who underwent 3 Tesla MR imaging and curative-intent intervention for MRI-staged Tis/T1/T2 rectal cancer from March 2012 to December 2016 were included. The radiological T category of each rectal tumour was compared retrospectively with histopathological results assessed according to the tumor, node, metastasis (TNM) classification. The sensitivities, specificities, and overall accuracy rates of 3 Tesla MR imaging for Tis, T1, and T2 cases were calculated using MedCalc statistical software v. 16. RESULTS: The sensitivity, specificity, PPV, NPV of 3 Tesla MR imaging in T categorization for T2 were: 93.7% [95% CI (0.79-0.99)], 77.7% [95% CI (0.52-0.93)], 88.2% [95% CI (0.75-0.94)] and 87.5% [95% CI (0.64-0.96)]; for T1 were 92% [95% CI (0.63-0.99)], 91.8% [95% CI (0.78-0.98)], 80% [95% CI (0.57-0.92)] and 97.1% [95% CI (0.83-0.99)]; for Tis were: 20% [95% CI (0.51-0.71)], 100% [95% CI (0.92-1)], 100%, 91.8% [95% CI (0.87-0.94)], respectively. MR categorization accuracy rates for T2, T1 and Tis were calculated as 88, 92 and 92%, respectively. CONCLUSION: 3 Tesla MR imaging seems to be useful for accurate categorization of T-stage in early rectal cancer, especially for T1 cancers. The method is not a reliable tool to detect Tis cases. The potential for overstaging and understaging of the technique should be realized and taken into consideration when tailoring the treatment protocol for each patient. Advances in knowledge: High-resolution MR with phased-array coil is being increasingly used in the pre-operative assessment of rectal cancer. 3 Tesla high-resolution MR imaging allows improved definition of bowel wall and tumour infiltration.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/patología , Imagen por Resonancia Magnética/métodos , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad
16.
AJR Am J Roentgenol ; 189(2): W84-9, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17646444

RESUMEN

OBJECTIVE: The purpose of this study was to establish the role of MR cholangiopancreatography (MRCP) in the diagnosis of biliary rupture in hepatic hydatid disease. We sought to determine whether the morphologic features of cysts and bile duct abnormalities detected on MRCP are specific enough for identification of intrabiliary rupture. CONCLUSION: If one of the following MRCP findings of apparent connection between hydatid cyst and biliary system, deformation of cyst, focal defect in cyst wall, or beaklike projection extending from cyst wall was present in a patient with hepatic hydatid cyst, the sensitivity of MRCP was 91.7% and the specificity was 82.8% for identification of intrabiliary rupture.


Asunto(s)
Pancreatocolangiografía por Resonancia Magnética/métodos , Equinococosis Hepática/diagnóstico , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Rotura Espontánea
17.
Curr Probl Diagn Radiol ; 36(1): 48-50, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17198892

RESUMEN

Synovial cyst is an uncommon cause of back pain and radiculopathy. This case report describes the magnetic resonance imaging findings of two lumbar synovial cysts with special emphasis on the differential diagnoses of other extradural cystic lesions.


Asunto(s)
Dolor de Espalda/etiología , Quiste Sinovial/complicaciones , Quiste Sinovial/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Quiste Sinovial/cirugía
18.
Comput Med Imaging Graph ; 30(8): 465-8, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17049208

RESUMEN

We present ultrasonographic and magnetic resonance imaging findings of intratesticular adrenal rests in a 16-year-old patient with congenital adrenal hyperplasia. Scrotal ultrasonography showed bilateral well-delineated homogenous hypoechoic lesions located around the mediastinum testis, which were highly vascularized on power Doppler ultrasonography. Relative to normal testicular parenchyma the lesions were iso- or hyperintense on T1-weighted and hypointense on T2-weighted images. T2-weighted images also showed a target-like appearance caused by a more hypointense peripheral halo around the lesions. The lesions enhanced remarkably on post-contrast images. This case suggests that radiological evaluation of testes, even in the presence of normal physical examination findings, should be included in periodical follow-up of patients with congenital adrenal hyperplasia. Magnetic resonance (MR) imaging is useful in demonstrating the lesions, because the contrast resolution better than with ultrasonography.


Asunto(s)
Hiperplasia Suprarrenal Congénita/diagnóstico por imagen , Hiperplasia Suprarrenal Congénita/patología , Tumor de Resto Suprarrenal/diagnóstico por imagen , Tumor de Resto Suprarrenal/patología , Neoplasias Testiculares/diagnóstico por imagen , Neoplasias Testiculares/patología , Adolescente , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Ultrasonografía
19.
Curr Probl Diagn Radiol ; 35(6): 258-60, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17084240

RESUMEN

A rare isolated cerebral varix of a superficial convexity cortical vein was described. On conventional magnetic resonance images, the varix was initially interpreted as a meningioma but a subsequent 3D magnetic resonance venography revealed the varix and the associated venous anatomy clearly.


Asunto(s)
Corteza Cerebral/irrigación sanguínea , Imagenología Tridimensional , Angiografía por Resonancia Magnética , Várices/diagnóstico , Adulto , Corteza Cerebral/patología , Medios de Contraste , Diagnóstico Diferencial , Femenino , Gadolinio DTPA , Humanos , Meningioma/diagnóstico , Várices/patología
20.
Diagn Interv Radiol ; 12(3): 125-8, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16972216

RESUMEN

PURPOSE: The aim of this retrospective study was to compare the splenic vein diameter and longitudinal size of the spleen in patients with portal hypertension in whom Gamna-Gandy bodies were present in their spleen with those of cirrhotic patients without Gamna-Gandy bodies and a control group. MATERIALS AND METHODS: Between July 2001 and February 2006, patients in whom Gamna-Gandy bodies were detected in their spleen and the number of patients who had been undergone magnetic resonance (MR) imaging with the diagnosis of chronic liver disease were determined. A total of 43 cases with Gamna-Gandy bodies were noted. Out of these patients, a case of lymphoma was excluded from the study. Additional 3 cases with splenic vein thrombosis were not included in statistical analysis. Accordingly, the splenic vein diameter and longitudinal size of the spleen in 39 patients (group 1: 12 women, 27 men; mean age, 38.5 years) with portal hypertension in whom Gamna-Gandy bodies were detected in their spleen on T1-weighted gradient-echo MR images between July 2001 and February 2006 were measured. The values obtained were compared with those of 29 cirrhotic patients without Gamna-Gandy bodies (group 2: 14 women, 15 men, mean age 48.2 years) and control group (group 3: 13 women, 18 men, mean age 46.8 years). The differences between the groups were analyzed with ANOVA and student-t test. RESULTS: Gamna-Gandy bodies were detected in 6.3% (42/670) of patients with chronic liver disease. The mean longitudinal axis of the spleen (20.2+/-4.2 cm) in group 1 was significantly greater (p<0.001) than in group 2 (14.4+/-3.9 cm). The mean splenic vein diameter was significantly larger in group 1 (14.3+/-4.0 mm) than those in groups 2 and 3 (11.2+/-3.2 mm and 7.8+/-1.4 mm, respectively). CONCLUSION: The splenic vein diameter and longitudinal size of the spleen in portal hypertensive patients with Gamna- Gandy bodies are significantly larger than that of cirrhotic patients without Gamna-Gandy bodies and that of control group.


Asunto(s)
Hipertensión Portal/complicaciones , Cirrosis Hepática/complicaciones , Imagen por Resonancia Magnética/métodos , Bazo/patología , Vena Esplénica/anatomía & histología , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Bazo/irrigación sanguínea , Enfermedades del Bazo
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