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1.
J Clin Endocrinol Metab ; 91(4): 1423-7, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16403821

RESUMEN

CONTEXT: Adults with Klinefelter's syndrome (KS) are known to present disturbances of language skills and delayed learning abilities. OBJECTIVES: The aim of this study was to assess brain morphometry in KS and to correlate eventual volumetric changes with performance on neuropsychological tests. PATIENTS: Patients included 18 KS adults and 20 age-matched controls. METHODS: All participants underwent prospectively double-spin-echo brain magnetic resonance imaging and neuropsychological testing of verbal and nonverbal domains. On the axial stack of magnetic resonance imaging slices, regional brain volumes were measured either by automated segmentation (full brain, total cerebrospinal fluid, and ventricular volume) or manual drawing with help of a neuroanatomy atlas (frontal, temporal, and parietal lobes, gray matter component of the lobes, cerebellar hemispheres, and hippocampal complexes). RESULTS: KS patients performed significantly lower than controls on language-related tasks exploring verbal processing speed and verbal executive function. They were diagnosed with significant enlargement of ventricular volume and bilateral reduction of cerebellar hemispheres. Furthermore, after separation of participants according to handedness and after correction of regional brain volumes for atrophy, a significant reduction of left temporal lobe volume was found in KS compared with controls. Ventricular volume was inversely correlated with cognitive function, whereas left temporal lobe volume was positively correlated with language-related tasks. CONCLUSION: This study hypothesizes that supernumerary X-chromosome and/or congenital hypogonadism provoke structural alterations in the subcortical pathways involved in language processing, thus providing a neurobiological substrate for cognitive deficits in KS.


Asunto(s)
Encéfalo/patología , Trastornos del Conocimiento/patología , Trastornos del Conocimiento/psicología , Síndrome de Klinefelter/patología , Síndrome de Klinefelter/psicología , Adolescente , Adulto , Ventrículos Cerebrales/patología , Femenino , Lateralidad Funcional/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Testosterona/farmacología
2.
J Natl Cancer Inst ; 90(11): 846-9, 1998 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-9625173

RESUMEN

BACKGROUND: In randomized trials, screening mammography has led to decreased mortality from breast cancer. However, the low positive predictive value of mammography (i.e., the proportion of patients with a positive test result who actually have breast cancer) results in a large number of unnecessary biopsies. We determined whether scintimammography with technetium-99m-sestamibi is a useful supplemental diagnostic tool for women with nonpalpable breast abnormalities identified by conventional mammography. METHODS: Scintimammography was performed preoperatively on 70 women who were 31-66 years of age (mean age and median age = 51 years). These women had nonpalpable breast abnormalities identified by conventional mammography; subsequently, a needle-localization excisional biopsy of each suspicious lesion was performed. Scintimammographic images were interpreted independently by two nuclear medicine physicians who were blinded to all clinical and pathologic data, and an interobserver variation analysis was performed. RESULTS: Interobserver variation analysis of the scintimammographic findings showed an agreement for breast diagnosis of 97% and a kappa coefficient of 0.90. Comparison of scintimammographic findings and histopathologic results revealed that the sensitivity (proportion of patients with breast cancer who had a positive test result), the specificity (proportion of patients without breast cancer who had a negative test result), the positive predictive value and the negative predictive value (proportion of patients with a negative test result who actually did not have breast cancer) of scintimammography were 56% (95% confidence interval [CI] = 23%-85%), 87% (95% CI = 75%-94%), 38% (95% CI = 15%-68%), and 93% (95% CI = 82%-98%), respectively. Four of nine breast cancers were not detected by scintimammography. CONCLUSION: Because of excellent interobserver agreement, scintimammography provides an objective way of detecting primary breast carcinoma. In view of its low sensitivity and positive predictive value, however, scintimammography is not currently recommended as a screening test in patients with nonpalpable positive mammographic findings.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Mamografía/métodos , Tecnecio Tc 99m Sestamibi , Adulto , Anciano , Biopsia , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/diagnóstico por imagen , Carcinoma Ductal de Mama/patología , Carcinoma Intraductal no Infiltrante/diagnóstico por imagen , Carcinoma Intraductal no Infiltrante/patología , Estudios de Evaluación como Asunto , Reacciones Falso Negativas , Femenino , Humanos , Tamizaje Masivo , Persona de Mediana Edad , Variaciones Dependientes del Observador , Palpación , Valor Predictivo de las Pruebas , Cintigrafía , Estudios Retrospectivos , Sensibilidad y Especificidad , Método Simple Ciego
3.
J Nucl Med ; 17(1): 26, 1976 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1244443

RESUMEN

We have observed increased activity over the neck on radionuclide angiograms of two patients with cervical lymphadenitis. This incidental findings should not be confused with other causes of locally increased perfusion.


Asunto(s)
Linfadenitis/diagnóstico , Cintigrafía , Adulto , Femenino , Humanos , Tecnecio
4.
J Nucl Med ; 16(5): 343-7, 1975 May.
Artículo en Inglés | MEDLINE | ID: mdl-1194984

RESUMEN

Exogenous fibrinogen has been successfully labeled with 99mTc using a modified electrolytic method. The exact labeling mechanism has not been determined. Experimental data suggest that the labeling process of 99mTc-fibrinogen is quite similar to that of 99mTc-human serum albumin as reported earlier by Benjamin. Technetium-99m-fibrinogen is stable in human plasma or in 1% buffered human serum albumin. A binding efficiency of 76% has been achieved with approximately 25% clottable protein. The entire labeling procedure requires less than 1 hr of preparation time. This short labeling time in a closed system may allow development of a practical method for labeling autologous fibrinogen, thus eliminating the risk of hepatitis transmission.


Asunto(s)
Fibrinógeno , Marcaje Isotópico/métodos , Tecnecio , Humanos
5.
J Nucl Med ; 16(5): 368-9, 1975 May.
Artículo en Inglés | MEDLINE | ID: mdl-1194987

RESUMEN

Sequential frames of different portions of the cardiac cycle are gated into a minicomputer by using an EKG signal recorded onto digital tape simultaneously with imaging information. Serial display of these frames on the computer oscilloscope or projection of 35-mm half frames of these images provides a cardiac motion image with information content adequate for qualitatively assessing cardiac motion.


Asunto(s)
Pruebas de Función Cardíaca/instrumentación , Películas Cinematográficas , Radioisótopos , Humanos
6.
J Nucl Med ; 16(6): 469, 1975 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1159501

RESUMEN

This report presents a patient with a persistent left superior vena cava demonstrated by radionuclide angiocardiography. The appearance is characteristic.


Asunto(s)
Cintigrafía , Vena Cava Superior/anomalías , Adulto , Femenino , Humanos , Tecnecio
7.
J Nucl Med ; 17(10): 937-8, 1976 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-966063

RESUMEN

Rectilinear scans are usually recorded on 14 X 17-in. x-ray film. This is costly both in terms of film and storage space. Using 4 X 5-in. film instead of the larger film will reduce this cost. An Ohio-Nuclear Model 84FD dual-probe 5-in. scanner was converted for the production of scan images directly on 4 X 5-in film (Kodak SO-79 nuclear medicine film). The smaller images may be viewed directly on a standard x-ray viewbox, or they may be projected if a larger image is desired. The image quality is excellent. This system has replaced the 14 X 17-in. film at our institution.


Asunto(s)
Fotograbar
8.
J Nucl Med ; 17(11): 975-6, 1976 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-985674

RESUMEN

By using the arterial and venous phases of an anterior cerebral perfusion study, which showed downward displacement of the sagittal sinus, and the finding of a "rim" on the delayed scans, the specific diagnosis of epidural hematoma was established.


Asunto(s)
Hematoma Epidural Craneal/diagnóstico , Cintigrafía , Adulto , Humanos , Masculino , Tecnecio
9.
J Nucl Med ; 38(7): 1019-22, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9225782

RESUMEN

UNLABELLED: Scintimammography with 99mTc-sestamibi can be used as a complementary technique to improve the mammogram's sensitivity and specificity for detection of breast carcinoma. We have observed in some patients focal areas of increased 99mTc-sestamibi uptake with no corresponding abnormalities on physical examination or mammogram. A phantom device and a special needle were designed to stereotactically localize these lesions before biopsy. METHODS: After intravenous injection of 30 mCI (1110 MBq) of 99m Tc-sestamibi, a prone lateral image of the abnormal breast was obtained. With the patient in the prone position, the breast was compressed with two fenestrated plates in the prone position. The x and y coordinates of the abnormal hot spot of the breast were determined. The z coordinate of focal 99mTc-sestamibi uptake was determined by advancing a localizer needle through a selected predetermined hole of the fenestrated plate using real-time visualization on the persistence monitor. The tip of the opturator inside the needle is welded with 57Co to determine the depth of the hot spot in the breast. RESULTS: Three women, all of whom had normal mammogram and breast physical examinations, were studied using 99mTc-sestamibi prone breast imaging. Pre-excisional biopsy needle localization of abnormal focal uptake was performed. Two women demonstrated infiltrative ductal carcinoma, and the third had proliferative fibrocystic disease of the breast. CONCLUSION: Our initial experience demonstrates that nuclear medicine guided stereotactic needle biopsy of the breast in patients with positive scintimammograms is technically feasible. In the future, this technology will enable us to detect breast carcinoma in the absence of clear-cut clinical and mammographic findings.


Asunto(s)
Biopsia con Aguja/métodos , Mama/diagnóstico por imagen , Mama/patología , Mamografía , Técnicas Estereotáxicas , Adulto , Biopsia con Aguja/instrumentación , Femenino , Humanos , Persona de Mediana Edad , Fantasmas de Imagen , Cintigrafía , Radiofármacos , Sensibilidad y Especificidad , Tecnecio Tc 99m Sestamibi
10.
J Nucl Med ; 23(3): 229-34, 1982 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7062136

RESUMEN

The sensitivity and specificity of Tc-99m-labeled antibacterial antibody (Tc-99m Ab) for detecting bacterial endocarditis were evaluated in an experimental model. Rabbit-produced antistaphylococcal antibody was extracted using Rivanol and chemically labeled with Tc-99m. This Tc-99m Ab was injected intravenously in New Zealand rabbits 24 hr after producing Staphylococcus aureus endocarditis of the aortic valve. Imaging and tissue analyses were performed on the following day. All 11 animals developed S. aureus aortic-valve vegetations and showed increased uptake of Tc-99m Ab at the aortic valve, 118 times higher than at the uninfected tricuspid valve. Although high hepatic radioactivity and anatomic uncertainties interfered with in vivo delineation of these lesions, images of the excised hearts showed all affected valves. Two rabbits inoculated with Escherichia coli did not develop endocarditis and had little uptake of Tc-99m Ab, while six rabbits with enterococcal endocarditis had no uptake of the Tc-99m Ab in their vegetations. The findings suggest potential value of Tc-99m Ab on the rapid diagnosis of endocarditis.


Asunto(s)
Anticuerpos Antibacterianos , Endocarditis Bacteriana/diagnóstico por imagen , Tecnecio , Animales , Femenino , Marcaje Isotópico , Masculino , Conejos , Cintigrafía , Infecciones Estafilocócicas/diagnóstico por imagen , Staphylococcus aureus/inmunología , Distribución Tisular
11.
Semin Nucl Med ; 11(4): 258-65, 1981 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6272421

RESUMEN

Salivary gland imaging with 99mTc as pertechnetate provides functional information concerning trapping and excretion of the parotid and submandibular glands. Anatomic information gained often adds little to clinical evaluation. On the other hand, functional information may detect subclinical involvement, which correlates well with biopsy of the minor labial salivary glands. Salivary gland abnormalities in systemic disease such as sarcoidosis, rheumatoid arthritis, lupus erythematosus, and other collagenvascular disorders may be detected before they result in the clinical manifestaions of Sjögren's syndrome. Such glands, after initially demonstrating increased trapping in the acute phase, tend to have decreased trapping and failure to discharge pertechnetate in response to an appropriate physiologic stimulus. Increased uptake of gallium-67 citrate often accompanies these findings. Inflammatory parotitis can be suspected when increased perfusion is evident on radionuclide angiography with any agent. The ability of the salivary gland image to detect and categorize mass lesions, which result in focal areas of diminished activity such as tumors, cysts, and most other masses, is disappointing, while its ability to detect and categorize Warthin's tumor, which concentrates pertechnetate, is much more valuable, although not specific.


Asunto(s)
Enfermedades de las Parótidas/diagnóstico por imagen , Enfermedades de las Glándulas Salivales/diagnóstico por imagen , Enfermedades de la Glándula Submandibular/diagnóstico por imagen , Tecnecio , Adenolinfoma/diagnóstico por imagen , Humanos , Linfangioma/diagnóstico por imagen , Neoplasias de la Parótida/diagnóstico por imagen , Cintigrafía , Síndrome de Sjögren/diagnóstico por imagen , Pertecnetato de Sodio Tc 99m , Neoplasias de la Glándula Submandibular/diagnóstico por imagen
12.
Chest ; 84(5): 522-8, 1983 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6313303

RESUMEN

Thirty-one patients with biopsy-confirmed sarcoidosis were studied for two to four years to compare serum angiotensin-converting enzyme (ACE) levels to clinical status, 67gallium scans, chest x-ray films, and pulmonary function tests (PFTs). Serum ACE levels and changes in ACE level correlated best with the clinical status of patients and their gallium scans (p less than 0.0005), and less with their chest x-ray films (p = 0.012) or PFTs (p = 0.007). The gallium scan was especially useful for localizing areas of disease involvement. Serial measurements of serum ACE were found to be a sensitive means for following the clinical course of patients with sarcoidosis and at times for predicting clinical relapse or improvement.


Asunto(s)
Enfermedades Pulmonares/enzimología , Peptidil-Dipeptidasa A/sangre , Sarcoidosis/enzimología , Adolescente , Adulto , Anciano , Femenino , Radioisótopos de Galio , Humanos , Estudios Longitudinales , Enfermedades Pulmonares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Radiografía , Cintigrafía , Pruebas de Función Respiratoria , Sarcoidosis/diagnóstico por imagen
13.
Arch Surg ; 122(10): 1139-40, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3662792

RESUMEN

Review of three-phase bone imaging results in three patients with gangrene of the toes showed a unique pattern of absent perfusion and absent bony and soft-tissue uptake. In one of these patients, characteristic bone imaging findings were present before clear-cut clinical presentation. In our experience, the finding of absent uptake in a particular clinical setting is highly specific for gangrene.


Asunto(s)
Huesos/diagnóstico por imagen , Gangrena/diagnóstico por imagen , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteomielitis/diagnóstico , Cintigrafía , Medronato de Tecnecio Tc 99m , Dedos del Pie/diagnóstico por imagen
14.
Arch Surg ; 110(1): 58-63, 1975 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1115610

RESUMEN

In nine patients with lower extremity symptoms of arterial insufficiency, potassium chloride K 43 was injected intravenously during rest, reactive hyperemia, or exercise. Decreased radioactivity in muscle tissue was observed to correspond with symptoms, physical findings, Doppler ultrasound pressures, and angiographic findings in all six who had the procedure. Studies following surgical endarteractomies in two, a bypass procedure in one, and exploration without attempted reconstruction in one showed good correlation with postoperative symptoms, physical findings, and pressure measurements using Doppler ultrasound in three of four patients. The fourth patient showed no change on the postoperative study despite clinical imporvement. These findings suggest that intravenously administered radioactive potassium provides a noninvasive means for demonstrating the perfused muscle mass of the extremities with delieation of ischemic areas. The risk of arterial puncture is eliminated, and the ability to visualize perfusion patterns during exercise is unique to this method.


Asunto(s)
Arteriopatías Oclusivas/diagnóstico , Pierna/irrigación sanguínea , Isótopos de Potasio , Cintigrafía , Adulto , Anciano , Angiografía , Arteriopatías Oclusivas/metabolismo , Femenino , Humanos , Isquemia/diagnóstico , Isquemia/metabolismo , Masculino , Persona de Mediana Edad , Músculos/metabolismo , Esfuerzo Físico , Isótopos de Potasio/metabolismo , Descanso
15.
Psychiatry Res ; 98(1): 15-28, 2000 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-10708923

RESUMEN

3,4-methylenedioxymethamphetamine (MDMA), an illicit recreational drug, damages serotonergic nerve endings. Since the cerebrovasculature is regulated partly by the serotonergic system, MDMA may affect cerebral blood flow (CBF) in humans. We evaluated 21 abstinent recreational MDMA users and 21 age- and gender-matched healthy subjects with brain SPECT and MRI. Ten of the MDMA subjects also had repeat SPECT and MRI after receiving two doses of MDMA. Abstinent MDMA users showed no significantly different global or regional CBF (rCBF) compared to the control subjects. However, within 3 weeks after MDMA administration, rCBF remained decreased in the visual cortex, the caudate, the superior parietal and dorsolateral frontal regions compared to baseline rCBF. The decreased rCBF tended to be more pronounced in subjects who received the higher dosage of MDMA. Two subjects who were scanned at 2-3 months after MDMA administration showed increased rather than decreased rCBF. Low-dose recreational MDMA use does not cause detectable persistent rCBF changes in humans. The lack of long-term rCBF changes may be due to a non-significant effect of serotonergic deficits on rCBF, or regeneration of serotonergic nerve terminals. The subacute decrease in rCBF after MDMA administration may be due to the direct effect of MDMA on the serotonergic system or the indirect effects of its metabolites on the dopaminergic system; the preliminary data suggest these effects may be transient.


Asunto(s)
Encéfalo/efectos de los fármacos , Circulación Cerebrovascular/efectos de los fármacos , Imagen por Resonancia Magnética , N-Metil-3,4-metilenodioxianfetamina/efectos adversos , Serotoninérgicos/efectos adversos , Tomografía Computarizada de Emisión de Fotón Único , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Estudios de Casos y Controles , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , N-Metil-3,4-metilenodioxianfetamina/administración & dosificación , Radiofármacos , Serotoninérgicos/administración & dosificación , Exametazima de Tecnecio Tc 99m , Factores de Tiempo
16.
J Thorac Imaging ; 5(3): 1-8, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2194037

RESUMEN

Radionuclide techniques used for the diagnosis and study of ARDS include the routine clinical procedures of perfusion lung scanning, gallium and white-cell imaging, as well as PET, indicator dilution methods for measuring extravascular lung water, and means of measuring protein accumulation, protein flux, and solute transfer. The techniques that reflect the rate of protein leak from the microvasculature and sensitive measures of rapidly reversible alveolar injury appear most promising. While clinical usefulness remains to be documented, these methods may ultimately assist with the diagnosis of ARDS and with the evaluation of prognosis and therapy.


Asunto(s)
Síndrome de Dificultad Respiratoria/diagnóstico por imagen , Humanos , Cintigrafía , Síndrome de Dificultad Respiratoria/fisiopatología
17.
Angiology ; 30(4): 257-61, 1979 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-443591

RESUMEN

To ascertain the prognostic value of the radionuclide angiogram in ischemic cerebral vascular disease, we reviewed the results of this study in 2200 patients who underwent this procedure. The arterial phase showed decreased activity in 175 patients studied in detail during the acute phase of their neurologic illnesses. In the 120 patients who proved to have ischemic disease and persisting neurologic signs, two basic patterns appeared during the venous phase: (1) no increased (diminished or equal) perfusion, or (2) increased perfusion. Following the initial incident, the clinical course varied from no change to marked clinical improvement. In the first group with either diminished or equal venous perfusion, the chances against improvement are greater than 6:1. In the latter group the chances for improvement or deterioration are equal.


Asunto(s)
Trastornos Cerebrovasculares/diagnóstico por imagen , Arterias , Humanos , Pronóstico , Cintigrafía , Venas
18.
Clin Nucl Med ; 22(4): 222-6, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9099476

RESUMEN

The authors report two cases of parathyroid imaging with double-phase Tc-99m sestamibi used in conjunction with Tc-99m pertechnetate that detected parathyroid hyperplasia when the wash out rate of MIBI from the glands paralleled normal thyroid tissue. Routine use of thyroid images for comparison may avoid this pitfall. The authors also observed that Tc-99m sestamibi has early uptake in brown tumors.


Asunto(s)
Hiperparatiroidismo/diagnóstico por imagen , Lipoma/diagnóstico por imagen , Neoplasia Endocrina Múltiple Tipo 1/diagnóstico por imagen , Neoplasias de las Paratiroides/diagnóstico por imagen , Seudohipoparatiroidismo/diagnóstico por imagen , Tecnecio Tc 99m Sestamibi , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adulto , Femenino , Humanos , Hiperplasia/diagnóstico por imagen , Masculino , Radiografía , Radiofármacos , Sensibilidad y Especificidad , Pertecnetato de Sodio Tc 99m , Glándula Tiroides/diagnóstico por imagen
20.
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