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1.
Acad Radiol ; 8(4): 335-42, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11293782

RESUMEN

RATIONALE AND OBJECTIVES: This study evaluated the specificity of ultrasound (US) characteristics of solid breast lesions and the interreader variability in their interpretation. MATERIALS AND METHODS: In 61 patients, 70 sonographically visible solid masses, scheduled for biopsy because of findings from conventional imaging, were prospectively and sequentially accrued for evaluation. Three readers interpreted the sonograms and described the solid masses in terms of established US characteristics. The specificity and positive predictive value (PPV) for each characteristic were calculated by comparing US findings with biopsy findings, and interreader variability was evaluated. Five assessment categories were developed to guide recommendations for patient care. The relative performance of each reader was assessed by measuring the PPV for each assessment category and by measuring the area under the receiver operating characteristic curve. RESULTS: The specificity and PPV were calculated for all characteristics and for each reader. The average specificities of the three readers for the most frequently used six characteristics were as follows: spiculation, 97%+/-5 (standard deviation); taller than wide, 91%+/-4; central shadowing, 77%+/-1; markedly hypoechoic, 86%+/-5; duct extension, 95%+/-5; and microlobulation, 84%+/-3 (overall average specificity, 88.5%). The average PPVs for categories II-V were 5%, 10%, 63%, and 94%, respectively. The readers' interpretations were similar and correlated well. CONCLUSION: The proposed US recommendation system is an accurate predictor of histologic findings. A sonographic classification lexicon should prove valuable.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Ultrasonografía Mamaria , Mama/patología , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/patología , Femenino , Humanos , Persona de Mediana Edad , Variaciones Dependientes del Observador , Proyectos Piloto , Valor Predictivo de las Pruebas , Curva ROC , Distribución Aleatoria , Sensibilidad y Especificidad
2.
J Ultrasound Med ; 19(7): 427-40; quiz 441-2, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10898296

RESUMEN

Seventy-four biopsy proven breast masses were imaged by color and power Doppler imaging to evaluate vascular pattern of malignant and benign breast masses. The images were analyzed for vascularity. The measurements were made over the entire mass as well as regionally at its core, at its periphery, and in the tissue surrounding it. The surgical specimens were analyzed for microvessel density. The diagnostic performance of Doppler sonographic vascularity indices was evaluated by receiver operating characteristic analysis. The malignant masses were 14 to 54% more vascular than the benign masses. Both types of masses were more vascular by ultrasonography than the tissue surrounding them. Whereas benign masses were 2.2 times more vascular than the surrounding tissue, the malignant masses were 5.0 times more vascular. In a subset of patients the regional vascularity at the core, periphery, and surrounding tissue by Doppler imaging exhibited a strong correlation (R2 > 0.9) with the corresponding histologic microvessel density measurements. Although the malignant masses exhibited a strong gradient in vascularity, core > periphery > surrounding tissue, the benign masses had relatively uniform distribution of vascularity. The area under the receiver operating characteristic curve (A(Z)) for the Doppler indices ranged from 0.56 +/- 0.07 to 0.65 +/- 0.07. A nonlinear analysis including age-specific values of Doppler indices improved the diagnostic performance to A(Z) = 0.85 +/- 0.06. In conclusion, quantitative Doppler imaging when used in combination with a nonlinear rule-based approach has the potential for differentiating between malignant and benign masses.


Asunto(s)
Neoplasias de la Mama/irrigación sanguínea , Neoplasias de la Mama/diagnóstico por imagen , Ultrasonografía Doppler , Ultrasonografía Mamaria , Adulto , Anciano , Área Bajo la Curva , Biopsia , Mama/patología , Neoplasias de la Mama/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Microcirculación , Persona de Mediana Edad , Neovascularización Patológica , Curva ROC , Sensibilidad y Especificidad
4.
AJR Am J Roentgenol ; 172(4): 983-8, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10587132

RESUMEN

OBJECTIVE: Our goal was to determine if normal and abnormal pregnancies could be distinguished at smaller sac sizes with a higher frequency transvaginal transducer than with a 5-MHz transducer. SUBJECTS AND MATERIALS: Thirty-nine patients with potentially abnormal pregnancies identified with a 5-MHz transvaginal transducer were immediately reimaged with a 9-5-MHz transducer. We compared our ability to visualize the yolk sac, embryo, and cardiac activity relative to mean sac diameter on imaging at both frequencies in women with normal and abnormal pregnancies. RESULTS: Of the 39 pregnancies, 22 (56%) were normal or probably normal. Using the 5-MHz transducer, a yolk sac was first seen in a 6.4-mm gestational sac but was not definitively seen in 12 gestational sacs measuring 5-13 mm. Using the 9-5-MHz transducer, yolk sacs were identified in all gestational sacs measuring 4.6-13 mm, and live embryos were seen in five of eight sacs measuring 8.1-13 mm. The largest normal gestational sac without a live embryo measured 11 mm. When we compared these pregnancies with 17 (44%) abnormal pregnancies, we found that all pregnancies that had no yolk sac by the time the gestational sac measured 5.0 mm or no live embryo by 13 mm had abnormal findings on higher frequency imaging. CONCLUSION: The ability to visualize the yolk sac and embryo in early pregnancy is critically dependent on transvaginal transducer frequency. Threshold values and discriminatory sizes used to distinguish normal and abnormal pregnancies are smaller on higher frequency than on lower frequency imaging and, therefore, should be redetermined for specific transducer frequencies.


Asunto(s)
Complicaciones del Embarazo/diagnóstico por imagen , Ultrasonografía Prenatal , Adolescente , Adulto , Membranas Extraembrionarias/diagnóstico por imagen , Femenino , Humanos , Embarazo , Primer Trimestre del Embarazo , Ultrasonografía Prenatal/instrumentación , Ultrasonografía Prenatal/métodos
5.
J Vasc Interv Radiol ; 8(4): 549-56, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9232569

RESUMEN

PURPOSE: To evaluate the role of ultrasound (US) in the detection of elevated portosystemic gradients and loss of shunt function in patients with a transjugular intrahepatic portosystemic shunt (TIPS). MATERIALS AND METHODS: The authors' prospectively compared 151 Doppler hepatic sonograms with follow-up portal venograms in 64 patients with TIPS. Sonographic data from within the portal system, hepatic arteries, and three areas within the TIPS were collected. Statistical analysis of these parameters was used to establish the US criteria for shunt dysfunction. RESULTS: Midshunt velocity thresholds of less than 50 and less than 60 cm/sec yielded sensitivities and specificities of 46% and 93%, and 57% and 89%, respectively, for the detection of portosystemic gradients exceeding 15 mm Hg. Use of a threshold midshunt velocity of less than 60 cm/sec or main portal vein velocity of less than 40 cm/sec raised the shunt dysfunction detection sensitivity to 86%, with a specificity of 54%. CONCLUSION: Doppler US is an effective noninvasive screening tool for detecting elevated portosystemic gradients and evaluating the functional status of a TIPS. Midshunt velocities of less than 60 cm/sec or main portal vein velocities less than 40 cm/sec are a useful threshold for detecting shunt dysfunction.


Asunto(s)
Oclusión de Injerto Vascular/diagnóstico por imagen , Derivación Portosistémica Intrahepática Transyugular/efectos adversos , Complicaciones Posoperatorias/diagnóstico por imagen , Ultrasonografía Doppler/métodos , Adulto , Anciano , Velocidad del Flujo Sanguíneo , Estudios de Seguimiento , Oclusión de Injerto Vascular/fisiopatología , Arteria Hepática/diagnóstico por imagen , Arteria Hepática/fisiopatología , Humanos , Persona de Mediana Edad , Flebografía , Sistema Porta/diagnóstico por imagen , Sistema Porta/fisiopatología , Complicaciones Posoperatorias/fisiopatología , Estudios Prospectivos , Sensibilidad y Especificidad
6.
Radiology ; 203(1): 211-7, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9122395

RESUMEN

PURPOSE: To test the reliability of established ultrasound (US) parameters in predicting the outcome of first-trimester pregnancy. MATERIALS AND METHODS: The authors retrospectively reviewed 2,655 first-trimester US scans in 2,285 patients. Parameters tested against outcome were (a) a yolk sac and mean gestational sac diameter of 8 mm on transvaginal US scans, (b) an embryo and mean sac diameter of 16 mm on transvaginal US scans, and (c) a difference between the mean sac diameter and crown-rump length of less than 5 mm (oligohydramnios) at 5.5-9.0 weeks gestation. RESULTS: Thirty (22%) of 135 patients without yolk sacs and with an 8-mm mean sac diameter developed live embryos: 24 had normal follow-up or delivery; six were lost to follow-up. Five (8%) of 59 patients with no depiction of embryos and with a 16-mm mean sac diameter developed live embryos: Two delivered, one spontaneously aborted, one had death of one twin embryo before being lost to follow-up, and one was lost to follow-up. Seventeen (0.74%) of 2,285 patients had early oligohydramnios: Six (35%) had normal follow-up scans or delivery, two (12%) spontaneously aborted, and nine (53%) were lost to follow-up. CONCLUSION: Established parameters predictive of early pregnancy failure potentially result in misdiagnosis of nonviability or poor prognosis when applied to a large, unselected patient population. Close follow-up is necessary in cases with borderline abnormal findings.


Asunto(s)
Complicaciones del Embarazo/diagnóstico por imagen , Ultrasonografía Prenatal , Aborto Espontáneo/diagnóstico por imagen , Largo Cráneo-Cadera , Desarrollo Embrionario y Fetal , Femenino , Humanos , Oligohidramnios/diagnóstico por imagen , Embarazo , Resultado del Embarazo , Primer Trimestre del Embarazo , Estudios Retrospectivos , Sensibilidad y Especificidad , Saco Vitelino/diagnóstico por imagen
7.
Br J Radiol ; 70: 311-3, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9166060

RESUMEN

Clinical symptoms are rarely produced by ectopic pancreas arising in the jejunum. We report a case of a patient with left lower quadrant abdominal pain due to jejunal ectopic pancreas complicated by acute pancreatitis and pseudocyst formation.


Asunto(s)
Coristoma/complicaciones , Diverticulitis/complicaciones , Enfermedades del Yeyuno/complicaciones , Páncreas , Seudoquiste Pancreático/complicaciones , Pancreatitis/complicaciones , Enfermedad Aguda , Coristoma/diagnóstico , Diagnóstico Diferencial , Diverticulitis/diagnóstico , Urgencias Médicas , Humanos , Enfermedades del Yeyuno/diagnóstico , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
10.
J Urol ; 155(1): 228-31, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7490841

RESUMEN

PURPOSE: We evaluated the strategy for repeat biopsy of patients with prostatic intraepithelial neoplasia without concurrent carcinoma detected on prostate needle biopsy. MATERIALS AND METHODS: Of 1,275 consecutive patients undergoing prostate needle biopsy 61 were identified with prostatic intraepithelial neoplasia but without concurrent prostate carcinoma. Of the 61 patients 53 had undergone repeat biopsy. The medical records, transrectal ultrasound, and operative and pathological reports of these patients were reviewed. RESULTS: Repeat biopsy was done in 53 patients with prostatic intraepithelial neoplasia, yielding carcinoma in 15, prostatic intraepithelial neoplasia without carcinoma in 8 and benign tissue in 30. The yield of carcinoma from repeat biopsy of a prostatic intraepithelial neoplasia site was 8.3% (7 of 84 sites). A total of 18 sites of carcinoma was detected by repeat biopsy of a previous random biopsy site (8), a prostatic intraepithelial neoplasia site only (5), a transrectal ultrasound nodule (3), a palpable nodule and prostatic intraepithelial neoplasia site (1), and a transrectal ultrasound nodule and prostatic intraepithelial neoplasia site (1). Carcinoma was as frequently detected by repeat biopsy of a prostatic intraepithelial neoplasia site (6 patients) as by random repeat biopsy (6 patients). CONCLUSIONS: Repeat prostate needle biopsy of patients with prostatic intraepithelial neoplasia should include random repeat biopsy and repeat biopsy of transrectal ultrasound abnormalities as well as previous sites of prostatic intraepithelial neoplasia.


Asunto(s)
Adenocarcinoma/patología , Próstata/patología , Neoplasia Intraepitelial Prostática/patología , Neoplasias de la Próstata/patología , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/epidemiología , Anciano , Biopsia con Aguja , Humanos , Masculino , Próstata/diagnóstico por imagen , Neoplasia Intraepitelial Prostática/diagnóstico por imagen , Neoplasia Intraepitelial Prostática/epidemiología , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/epidemiología , Ultrasonografía
11.
Semin Roentgenol ; 30(4): 324-46, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8539643

RESUMEN

Hepatic sonography is useful in characterizing many focal liver lesions (Tables 2-6). It is safe, portable, and relatively inexpensive. With the development of color Doppler imaging, power Doppler imaging, and intravenous-ultrasound contrast agents, the ability to detect and precisely diagnose a focal hepatic lesion may be improved.


Asunto(s)
Hepatopatías/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Carcinoma Hepatocelular/diagnóstico por imagen , Medios de Contraste/administración & dosificación , Humanos , Inyecciones Intravenosas , Absceso Hepático/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Ultrasonografía Doppler/economía , Ultrasonografía Doppler/métodos , Ultrasonografía Doppler en Color/economía , Ultrasonografía Doppler en Color/métodos
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