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1.
AJNR Am J Neuroradiol ; 28(9): 1778-82, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17885244

RESUMEN

BACKGROUND AND PURPOSE: Thromboembolic events are the most common complications of elective coil embolization of cerebral aneurysms. Administration of oral clopidogrel and/or aspirin could lower the thromboembolic complication rate. MATERIALS AND METHODS: Records over a 10-year period were reviewed in a retrospective cohort study. For 369 consecutive elective coil embolization procedures, 25 patients received no antiplatelet drugs, 86 received antiplatelet drugs only after embolization, and 258 received antiplatelet drugs before and after embolization. RESULTS: Symptomatic thromboembolic complications (transient ischemic attack or stroke within 60 days) occurred in 4 (16%) of 25 when no antiplatelet drugs were given, in 2 (2.3%) of 86 when antiplatelet drugs were administered only after embolization, and in 5 (1.9%) of 258 when antiplatelet drugs were administered before and after embolization. The lower symptomatic thromboembolic complication rate in the patients who received any antiplatelet therapy was statistically significant (P = .004). Clots were visible intraprocedurally in 5 (4.5%) of 111 when no antiplatelet drugs were administered before procedures and in 4 (1.6%) of 258 when they were (P value not significant). None of the 9 was symptomatic postprocedurally, but 7 were lysed or mechanically disrupted. Extracerebral hemorrhagic complications occurred in 0 (0%) of 25 when no antiplatelet drugs were given and in 11 (3.2%) of 344 when they were (P value not significant). CONCLUSION: Oral clopidogrel and/or aspirin significantly lowered the symptomatic thromboembolic complication rate of elective coil embolization of unruptured cerebral aneurysms. There were trends toward a lower rate of intraprocedural clot formation in patients given antiplatelet drugs before procedures and a higher hemorrhagic complication rate in patients given antiplatelet drugs. Benefits of antiplatelet therapy appear to outweigh risks.


Asunto(s)
Embolización Terapéutica/estadística & datos numéricos , Aneurisma Intracraneal/epidemiología , Aneurisma Intracraneal/terapia , Trombosis Intracraneal/epidemiología , Trombosis Intracraneal/prevención & control , Inhibidores de Agregación Plaquetaria/administración & dosificación , Medición de Riesgo/métodos , Quimioterapia Adyuvante/métodos , Quimioterapia Adyuvante/estadística & datos numéricos , Comorbilidad , Embolización Terapéutica/instrumentación , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Missouri/epidemiología , Evaluación de Resultado en la Atención de Salud , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
2.
AJNR Am J Neuroradiol ; 28(9): 1736-42, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17885252

RESUMEN

BACKGROUND AND PURPOSE: This study was undertaken to analyze the outcomes and treatment-related complications of the polyglycolic/polylactic acid (PGLA)-coated Matrix platinum coils in the treatment of intracranial aneurysms and compare these results with those derived from the same single-institutional experience with use of uncoated, bare platinum coils. MATERIALS AND METHODS: In this study, we compared 2 groups of patients in a retrospective fashion. The first group consisted of 70 consecutive patients who underwent 82 aneurysm treatments with Matrix coils during the 14-month period of study, from January 2003 to February 2004. We compared this cohort with 70 consecutive patients who underwent a total of 80 aneurysm treatments with bare platinum coils in the 12 months immediately preceding the use of PGLA-coated coils, from January through December 2002. We then recorded the treatment characteristics, angiographic outcomes, and any complications. RESULTS: There were similar baseline demographic characteristics between the 2 study groups except in age, anatomic location, and length of follow-up. The overall recurrence rate of aneurysms was 41% among the Matrix-treated group and 32% among the patients treated with bare platinum. Among the 42 patients treated with 100% Matrix, the rate of recurrence was 31%. Of the recurrences, 21% of the Matrix group, 19% of the 100% Matrix group, and 9% of the bare platinum group required retreatment. The overall rate of complications was 10% in the Matrix-treated group and 7% in the bare platinum group. There was not a statistically significant difference in the rate of recurrence of aneurysms or complications between the 2 groups. CONCLUSIONS: On the basis of our single-center experience, there is insufficient evidence to support the use of Matrix coils over bare platinum coils, given their disadvantages.


Asunto(s)
Embolización Terapéutica/instrumentación , Embolización Terapéutica/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/terapia , Platino (Metal) , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Estudios Retrospectivos , Prevención Secundaria , Resultado del Tratamiento
3.
Chest ; 117(4): 991-8, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10767229

RESUMEN

OBJECTIVES: We used whole-lung quantitative CT analysis (QCT)-an objective method of evaluating emphysema severity and distribution based on measurement of lung density-to determine whether subjective selection criteria for lung volume reduction surgery are applied consistently and to model the patient selection process, and assessed the relationship of the model to postoperative outcome. DESIGN: Logistic regression analysis using QCT indexes of emphysema and preoperative physiologic test results as the independent variables, and the decision to operate as the dependent variable. SETTING: University hospital. PATIENTS: Seventy patients selected for bilateral lung volume reduction surgery and 32 otherwise operable patients excluded from surgery based on subjective assessment of emphysema morphology on chest radiography, CT, and perfusion scintigraphy. INTERVENTION: Bilateral lung volume reduction surgery in the selected group. MEASUREMENTS AND RESULTS: Emphysema in patients selected for surgery was more severe overall and in the upper lungs by multiple QCT indexes (p < 0.01, unpaired two-tailed t test). Physiologic abnormalities were slightly more severe in selected patients (p < 0.05, unpaired two-tailed t test). The range of many QCT and physiologic values overlapped considerably between the selected and excluded groups. The percent severe emphysema (<- 960 Hounsfield units [HU]), upper/lower lung emphysema ratio (- 900 HU threshold), and residual volume were the key variables in the model predicting selection decisions (model r(2) = 0.48; p < 0.0001). The model correctly predicted selection decisions in 87% of all cases, 91% of the selected group, and 78% of the excluded group. Surgical patients with a higher model-derived probability of selection had greater postoperative improvement in FEV(1) and 6-min walk distance. CONCLUSIONS: Radiologic selection criteria are applied consistently to the majority of patients. QCT features are strongly associated with selection decisions, are related to outcome, and may help improve consistency and confidence in patient selection.


Asunto(s)
Técnicas de Apoyo para la Decisión , Selección de Paciente , Neumonectomía/métodos , Enfisema Pulmonar/cirugía , Tomografía Computarizada por Rayos X , Adulto , Anciano , Femenino , Mortalidad Hospitalaria , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Enfisema Pulmonar/diagnóstico por imagen , Enfisema Pulmonar/fisiopatología , Reproducibilidad de los Resultados , Pruebas de Función Respiratoria , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
4.
Invest Radiol ; 29(10): 890-6, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7852040

RESUMEN

RATIONALE AND OBJECTIVES: Two independent gold standards and diagnoses from three-dimensional computed tomography (CT) images were used to examine the possibility that craniosynostosis is a binary abnormality that potentially may be diagnosed without error. METHODS: Surgical reports, histology of excised sutures, and three-dimensional CT images were compared for 25 children undergoing surgical management of craniosynostosis. Surgical reports identified sutures as normal or abnormal. Histology reported suture closure on a 5-point scale. Four radiologists used three-dimensional CT images to diagnose sutures on a 6-point rated response scale. RESULTS: Sutures with histology 0, 1, or 2 were normal on surgical reports, and those with histology 3 or 4 were abnormal. Most readers achieved nearly perfect sensitivity and specificity. Reader confidence was unrelated to degree of pathology. CONCLUSION: Craniosynostosis appears to be binary in our sample. Surgical reports, pathology results, and three-dimensional CT images read by experienced viewers achieved nearly perfect agreement.


Asunto(s)
Craneosinostosis/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Suturas Craneales/anomalías , Suturas Craneales/diagnóstico por imagen , Suturas Craneales/patología , Craneosinostosis/patología , Craneosinostosis/cirugía , Craneotomía , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Lactante , Masculino , Registros Médicos , Variaciones Dependientes del Observador , Hueso Occipital/anomalías , Hueso Occipital/diagnóstico por imagen , Hueso Occipital/patología , Hueso Parietal/anomalías , Hueso Parietal/diagnóstico por imagen , Hueso Parietal/patología , Estudios Prospectivos , Intensificación de Imagen Radiográfica/métodos , Sensibilidad y Especificidad
5.
AJNR Am J Neuroradiol ; 21(3): 451-4, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10730634

RESUMEN

BACKGROUND AND PURPOSE: Few studies have examined HIV-positive patients presenting with uncomplicated headache for clinical variables that might be predictive of those patients who would most benefit from CT. Because of the value of CD4 counts in predicting the relative risk of developing opportunistic infections and neoplasms, we assessed the diagnostic yield of screening CT in HIV-positive patients presenting with headache as sorted by CD4 count. METHODS: We reviewed CT scan results and CD4 counts in patients presenting with headache uncomplicated by altered mental status, meningeal signs, neurologic findings, or symptoms of subarachnoid hemorrhage. For analysis, scans were considered positive or negative and were grouped according to CD4 counts of less than 200 cells/microL, 200 to 499 cells/microL, and equal to or greater than 500 cells/microL. The results were then analyzed using the chi2 test. RESULTS: One hundred seventy-eight HIV-positive patients underwent a total of 204 unenhanced and contrast-enhanced CT examinations. One hundred twenty-eight (62.7%) of the scans were negative, and 76 (37.3%) were positive. Of the positive scans, 58 (76.3%) showed atrophy only and 18 (23.7%) showed mass lesions or white matter lesions. All cases that were positive for mass lesions or white matter lesions occurred in patients with CD4 counts less than 200 cells/microL (P = .04). CONCLUSION: A recent CD4 count provides an important predictor variable when considering performing CT in HIV-positive patients presenting with uncomplicated headache. Performing CT of the head for patients with CD4 counts equal to or greater than 200 cells/microL is of questionable value considering the low prevalence of positive CT findings. For this select group of patients, MR imaging may be more appropriate than CT. Patients with CD4 counts less than 200 cells/microL should undergo CT because of the high prevalence of positive scans.


Asunto(s)
Encéfalo/diagnóstico por imagen , Recuento de Linfocito CD4 , Seropositividad para VIH/complicaciones , Cefalea/complicaciones , Tomografía Computarizada por Rayos X , Adulto , Encefalopatías/complicaciones , Encefalopatías/diagnóstico , Encefalopatías/diagnóstico por imagen , Femenino , Seropositividad para VIH/inmunología , Cefalea/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
6.
AJNR Am J Neuroradiol ; 18(6): 1081-5, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9194435

RESUMEN

PURPOSE: To measure the mean cerebral circulation time (CCT) in patients with symptomatic vasospasm stemming from subarachnoid hemorrhage and to determine any change after papaverine treatment. METHODS: We studied 27 patients who received intraarterial papaverine from November 1992 to August 1995 to determine the CCT in 59 carotid territories. CCT was measured from the first image in which contrast was seen above the supraclinoid internal carotid artery to the peak filling of parietal cortical veins. Angiograms at the time of presentation were examined in 19 of the 27 patients. A control population of 19 patients (30 carotid territories) was also studied. RESULTS: The mean CCT on presentation was 6.8 seconds +/- 1.1. The prepapaverine mean CCT was 6.1 seconds +/- 1.2. The immediate postpapaverine mean CCT was 3.8 seconds +/- 0.8. CCT decreased in 58 of 59 territories treated with papaverine; the mean change was -35.7%. In eight of these patients, CCT rose on the following day to 6.1 seconds +/- 1.1. In the control group, mean CCT was 5.9 seconds +/- 0.8. The mean CCT in patients with subarachnoid hemorrhage was slightly prolonged on presentation relative to that in control subjects. CONCLUSION: Intraarterial papaverine produces a consistent decrease in CCT in patients with vasospasm.


Asunto(s)
Encéfalo/irrigación sanguínea , Ataque Isquémico Transitorio/tratamiento farmacológico , Papaverina/administración & dosificación , Hemorragia Subaracnoidea/complicaciones , Vasodilatadores/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Angiografía de Substracción Digital , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Angiografía Cerebral/efectos de los fármacos , Femenino , Humanos , Infusiones Intraarteriales , Masculino , Persona de Mediana Edad , Hemorragia Subaracnoidea/tratamiento farmacológico
7.
AJNR Am J Neuroradiol ; 15(10): 1861-9, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7863936

RESUMEN

PURPOSE: To measure diagnostic performance and preference of two three-dimensional CT reconstruction modalities (voxel-gradient and surface-projection) displayed two ways (conventional and unwrapped) in craniosynostosis confirmed by surgical inspection and histologic analysis of resected sutures. METHODS: High-resolution 2-mm contiguous CT sections were obtained and three-dimensional reconstruction images generated for 25 infants and children with skull deformities before surgical treatment of craniosynostosis. Two pediatric radiologists and two neuroradiologists first ranked images by their own preferences for diagnostic use. Then they diagnosed craniosynostosis from images presented in random order and blinded. The standard of reference was inspection during surgery and histologic evaluation of excised sutures. Finally, reviewers repeated their subjective preference tests. RESULTS: The least experienced radiologist had 100% sensitivity for all imaging modalities and specificities ranging from 43% to 83%. The two most experienced radiologists performed nearly identically, with sensitivities of 96% and specificities of 100%. After performing diagnostic tasks using all image types, all radiologists preferred conventional surface projections. CONCLUSION: Experienced readers can achieve nearly perfect diagnostic performance using the latest three-dimensional CT reconstruction images, making it a contribution to the diagnostic process. Although performance is nearly identical for all modalities, readers strongly prefer conventionally presented surface-projection images.


Asunto(s)
Craneosinostosis/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Gráficos por Computador , Suturas Craneales/diagnóstico por imagen , Suturas Craneales/patología , Suturas Craneales/cirugía , Craneosinostosis/patología , Craneosinostosis/cirugía , Femenino , Humanos , Lactante , Masculino , Programas Informáticos
8.
J Neurosurg ; 88(1): 38-42, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9420070

RESUMEN

OBJECT: This study was conducted to determine if there is a change in intracranial arterial diameters after papaverine infusion for vasospasm and to determine whether the change occurs in proximal, intermediate, and distal arteries. METHODS: The authors measured arterial diameters retrospectively in all patients who received intraarterial papaverine for treatment of vasospasm between November 1992 and August 1995. Patients who received papaverine in the same session with or following angioplasty were excluded. Measurements were made in a blinded manner with the aid of a magnification loupe at 12 predetermined sites on each angiogram before and after papaverine infusion. Eighty-one treatments in 34 patients were included. Angiograms obtained at the time of presentation with subarachnoid hemorrhage (SAH) were examined in 26 of the 34 patients. Nine carotid territories visualized by repeated angiography on the day after infusion were examined to determine the duration of the papaverine effect. CONCLUSIONS: In all treatment groups an increase was found in the average arterial diameters ranging from 2.8 to 73.9%, with a mean increase of 26.5%. Increases in diameter were observed in proximal, intermediate, and distal arteries. The timing of treatments ranged from Day 3 to Day 19 post-SAH, and there was no relationship between timing and arterial responsiveness (r = -0.06). There was a moderately good correlation between the degree of vasospasm in an artery and its responsiveness to papaverine (r = -0.54, -0.66, and -0.66, for proximal, intermediate, and distal arteries, respectively). The effect of papaverine did not persist until the following day in patients in whom repeated angiography was performed.


Asunto(s)
Arterias Cerebrales/efectos de los fármacos , Ataque Isquémico Transitorio/tratamiento farmacológico , Papaverina/administración & dosificación , Vasodilatadores/administración & dosificación , Angiografía de Substracción Digital , Arterias Cerebrales/diagnóstico por imagen , Femenino , Humanos , Infusiones Intraarteriales , Ataque Isquémico Transitorio/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Vasodilatación/efectos de los fármacos
9.
J Bone Joint Surg Am ; 79(6): 833-7, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9199379

RESUMEN

Torsion of a long bone is the twist along its longitudinal axis; torsion of the radius is defined by the angle between the proximal and distal metaphyses in the transverse plane. Measurement of the radial torsion angle provides a means of detection and quantification of malrotation after a fracture. The purpose of the current study was to develop and standardize a technique for the measurement of torsion of the radius. Axial computerized tomographic images of thirty-nine pairs of dry cadaver specimens of normal radii, and an additional four pairs of radii with a unilateral deformity of the distal metaphysis that was consistent with a previous fracture, were studied and a measurement protocol was established. The radial torsion angle was measured by three independent observers on two separate occasions. Reproducibility of the technique was determined with use of the intraclass correlation coefficient to express both interobserver and intraobserver reliability. Consistency of measurements between observers and by the same observer was high, with intraclass correlation coefficients ranging from 0.87 to 0.94. The mean torsion angle for the eighty-two normal radii in the study was 32.6 degrees (95 per cent confidence interval of the mean, 30.3 to 34.9 degrees; range, 1.4 to 58.8 degrees). There were small variations in torsion angle between the two radii of each normal pair (mean side-to-side difference, 4.9 degrees; 95 per cent confidence interval of the mean, 3.5 to 6.3 degrees). The mean torsion angle of the four radii with a malunited fracture was 10.4 degrees (95 per cent confidence interval of the mean, 5.7 to 15.1 degrees), and the mean side-to-side difference in the pairs containing these radii was 24.1 degrees (95 per cent confidence interval of the mean, 8.5 to 39.6 degrees; p < 0.0001 compared with the normal radii).


Asunto(s)
Radio (Anatomía)/fisiología , Tomografía Computarizada por Rayos X , Anciano , Anciano de 80 o más Años , Cadáver , Intervalos de Confianza , Antebrazo/fisiología , Fracturas Mal Unidas/diagnóstico por imagen , Fracturas Mal Unidas/fisiopatología , Fracturas Mal Unidas/cirugía , Humanos , Variaciones Dependientes del Observador , Osteotomía , Planificación de Atención al Paciente , Pronación , Radio (Anatomía)/diagnóstico por imagen , Fracturas del Radio/diagnóstico por imagen , Fracturas del Radio/fisiopatología , Fracturas del Radio/cirugía , Reproducibilidad de los Resultados , Rotación , Supinación
10.
Magn Reson Imaging ; 13(1): 1-8, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7898268

RESUMEN

A retrospective study of 164 patients undergoing dynamic contrast-enhanced magnetic resonance (MR) imaging was performed to assess hepatic parenchymal enhancement patterns and to correlate these patterns with hepatic function and disease. Rapid T1-weighted images were acquired before and after gadolinium administration. Hepatic enhancement patterns were analyzed blindly by two observers. Medical records were reviewed to document known liver pathology and liver function test results. A total of 72% of patients had homogeneous enhancement of the liver parenchyma; 28% had heterogeneous enhancement. Of the latter group, 61% of patients had enhancement conforming to segmental or lobar boundaries. Patients with heterogeneous enhancement patterns were more likely to have abnormal liver function test results and hepatic morphological abnormalities on their MR examinations than patients with homogeneous enhancement patterns. Heterogeneous hepatic enhancement on dynamic MR images is associated with a higher likelihood of liver disease and biochemical evidence of hepatic dysfunction than homogeneous enhancement.


Asunto(s)
Medios de Contraste , Hígado/patología , Imagen por Resonancia Magnética , Compuestos Organometálicos , Ácido Pentético/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Gadolinio DTPA , Humanos , Hígado/fisiopatología , Hepatopatías/diagnóstico , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
11.
Magn Reson Imaging ; 15(3): 275-85, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9201674

RESUMEN

This study aimed to determine the overall accuracy of known enhancement patterns for the characterization of a large series of focal hepatic masses on dynamic contrast-enhanced magnetic resonance (MR) images. Breath-hold T1-weighted images of the liver acquired before intravenous gadolinium administration and serially over 6-10 min after contrast injection were acquired in < 25 a using FLASH or rapid spin-echo pulse sequences. A total of 311 proven focal hepatic masses in 128 patients were analyzed, including 192 malignant lesions (166 metastases and 26 hepatomas) and 119 benign lesions (48 cavernous hemangiomas, 45 hepatic cysts, and 26 other abnormalities). The lesions were evaluated for a variety of characteristics independently by two reviewers who were blinded to results. Cavernous hemangiomas showed early peripheral nodular enhancement (80% sensitivity and 99% specificity) and hepatic cysts showed no enhancement (100% sensitivity and 95% specificity). Hepatic metastases showed variable, moderate enhancement (47% by one reviewer and 74% by the other). Metastatic lesions from hypervascular primary neoplasms displayed peak enhancement during the hepatic artery dominant (bolus) phase, while other malignant neoplasms showed later peak enhancement (72% sensitivity and 77% specificity). Five metastatic foci with early homogeneous enhancement showed a delayed peripheral washout of contrast (rim sign), while no nonmetastatic foci displayed this finding (3% sensitivity and 100% specificity). Characteristic enhancement patterns of focal hepatic lesions were described in a large series of patients. This study confirms results of previous investigators who have shown that early nodular peripheral enhancement was highly specific for hemangiomas and lack of enhancement was highly specific for hepatic cysts. Hypervascular metastatic foci show earlier peak enhancement than other malignant lesions. Some (2-3%) metastatic lesions display a peripheral washout of contrast on serial images, with 100% specificity.


Asunto(s)
Medios de Contraste , Neoplasias Hepáticas/diagnóstico , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/diagnóstico , Medios de Contraste/administración & dosificación , Quistes/diagnóstico , Combinación de Medicamentos , Femenino , Estudios de Seguimiento , Gadolinio/administración & dosificación , Gadolinio DTPA , Hemangioma Cavernoso/diagnóstico , Arteria Hepática , Humanos , Aumento de la Imagen/métodos , Inyecciones Intraarteriales , Inyecciones Intravenosas , Hepatopatías/diagnóstico , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/secundario , Masculino , Meglumina/administración & dosificación , Persona de Mediana Edad , Compuestos Organometálicos/administración & dosificación , Ácido Pentético/administración & dosificación , Ácido Pentético/análogos & derivados , Respiración , Estudios Retrospectivos , Sensibilidad y Especificidad , Método Simple Ciego
12.
Acad Radiol ; 3(7): 550-5, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8796716

RESUMEN

RATIONALE AND OBJECTIVES: We determined the prevalence of red marrow around the knee joint in adults and evaluated variations with age, gender, and other variables. METHODS: One hundred ninety-nine adult patients presenting for routine knee magnetic resonance (MR) imaging completed a questionnaire that covered age, gender, menstrual history, past pregnancies, smoking history, and medications. The presence or absence of visible red marrow in the distal femur and proximal tibia on both coronal and sagittal MR images was recorded for each patient. Associations between the presence of red marrow and the other recorded variables then were evaluated. RESULTS: Red marrow was present in more than half of the women and less than one sixth of the men, a statistically significant difference. The age distribution of red marrow in men and women also was different. Red marrow was the most common in women aged 30-60 years. In men, there was no clear-cut age trend. Red marrow also was more likely to be present in obese individuals and smokers. No association was found between the presence of red marrow and any of the other recorded variables. CONCLUSION: There are clear gender, age, obesity, and smoking-related differences in the prevalence of red marrow around the knee joint in adults. Red marrow is relatively common in this site in all age groups, and its presence should not be a cause for clinical concern.


Asunto(s)
Médula Ósea/anatomía & histología , Articulación de la Rodilla/anatomía & histología , Adolescente , Adulto , Anciano , Envejecimiento/fisiología , Peso Corporal , Médula Ósea/fisiología , Femenino , Fémur/anatomía & histología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Factores Sexuales , Tibia/anatomía & histología
13.
J Periodontol ; 61(10): 623-32, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2231229

RESUMEN

Quantitative alveolar bone loss evaluation by digital processing of dental radiographs was performed. More than 20 contrast and edge enhancement techniques were applied to bite-wing radiographs of adult molar teeth and the results subjectively evaluated. Wallis space variant image enhancement was selected as the most promising candidate for improved visualization of the cemento-enamel junctions and alveolar crests. Seventy-three skulls were radiographed, the films digitized, and enhancement performed on the digital images. Alveolar bone loss measurements from skulls (truth) were compared with those from the original radiographs, unprocessed digital images, and enhanced digital images. The average intraclass correlation coefficient for two observers was 0.83 for radiographs, 0.86 for digital images, and 0.91 for enhanced images. The intraclass correlation coefficient between the 2 sets of dry skull measurements made by two additional observers was 0.88. Means and 95% confidence limits were determined for differences between measurements from dry skulls and radiograph-based images. In the worst case for measurements from enhanced images, the mean difference from truth was -0.40 mm with a 95% confidence interval from -0.54 to -0.25 mm. Receiver operating characteristic (ROC) analysis was used to determine the utility of radiograph-based images for the diagnosis of vertical defects. The ability of two observers to diagnose vertical defects on dry skulls was also tested. All methods of vertical defect diagnosis, including the identification of vertical defects on dry skulls, had relatively low diagnostic performance. Image processing technology has considerable potential in periodontal disease studies for quantitative evaluations of alveolar bone height. The diagnosis of vertical defects using current definitions and techniques is problematic, with considerable room for improvement.


Asunto(s)
Pérdida de Hueso Alveolar/diagnóstico por imagen , Índice Periodontal , Radiografía de Mordida Lateral , Pérdida de Hueso Alveolar/patología , Proceso Alveolar/diagnóstico por imagen , Proceso Alveolar/patología , Análisis de Varianza , Diente Premolar/diagnóstico por imagen , Diente Premolar/patología , Cefalometría , Cemento Dental/patología , Esmalte Dental/patología , Humanos , Mandíbula , Diente Molar/diagnóstico por imagen , Diente Molar/patología , Variaciones Dependientes del Observador , Curva ROC , Intensificación de Imagen Radiográfica , Interpretación de Imagen Radiográfica Asistida por Computador , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
14.
J Periodontol ; 70(8): 829-33, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10476888

RESUMEN

BACKGROUND: The relationship between loss of radiographic alveolar bone height and probing attachment loss has been studied by a number of investigators, with mixed results. Recent studies have found weak correlations and have suggested that the relationship between bone loss and attachment loss is complex, perhaps because changes in bone height and attachment level are separated in time. METHODS: The 85 patients in this report were part of a prospective estrogen replacement interventional study. All patients were in good oral health at entry and received annual oral prophylaxis as part of the study. Standard probing measurements were made with a pressure-sensitive probe at 6 sites on each tooth. Vertical bite-wing radiographs were taken of each patient, radiographs were digitized, and 6 linear measurements (corresponding to probing site measurements) were made from the cemento-enamel junction to the alveolar crest. These procedures were performed at baseline and at annual intervals; this study reports results after 2 years. Data were analyzed both by individual site and by averaging identical sites from all measured teeth for each patient. RESULTS: Very weak direct relationships between change in alveolar bone height and change in attachment level were found in both the site data (r2=0.0022; P = 0.189) and the patient average data (r2=0.031; P= 0.104). CONCLUSIONS: The changes in these patients were probably due to systemic changes in bone health rather than to periodontal disease. However, the weak correlations between changes in attachment level and bone height are similar to recent studies of periodontal disease. Our results support suggestions in the literature that the link between changes in attachment and alveolar bone height is complex, perhaps because changes in the 2 tissue types are separated by a considerable time delay.


Asunto(s)
Pérdida de Hueso Alveolar/fisiopatología , Pérdida de la Inserción Periodontal/fisiopatología , Factores de Edad , Envejecimiento/fisiología , Pérdida de Hueso Alveolar/diagnóstico por imagen , Terapia de Reemplazo de Estrógeno , Femenino , Humanos , Modelos Lineales , Persona de Mediana Edad , Pérdida de la Inserción Periodontal/patología , Índice Periodontal , Bolsa Periodontal/patología , Estudios Prospectivos , Radiografía , Estadísticas no Paramétricas
15.
J Periodontol ; 71(3): 335-40, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10776919

RESUMEN

BACKGROUND: We set out to determine whether morphologic measurements extracted from digitized images of bite-wing radiographs correlated with lumbar and femoral bone mineral density (BMD) measurements in 45 postmenopausal women who had no or only mild periodontal disease (no probing depths >5 mm). METHODS: Lumbar spine and femoral BMDs were determined by dual-energy x-ray absorptiometry. Vertical bite-wing radiographs were taken and digitized. Crestal and apical regions of interest (ROIs) were drawn on the digital images of the maxillary and mandibular alveolar bone on the patient's right and left sides. For each patient, a single morphologic measurement was made for each of 8 ROIs. Correlation analysis was performed to determine the strengths of the relationships between the morphologic measurements made at the 8 locations and between these morphologic measurements and BMD measurements. RESULTS: The correlations (r) between the morphologic operator (MO) measurements and lumbar spine and femoral BMDs were weak (mean r = 0.02, range = 0.32 to -0.26) and not statistically significant, with no clear trends discernible. Correlations between MO measurements made at the 8 alveolar sites were also weak (mean r = 0.05, range = 0.35 to -0.38) and not statistically significant. CONCLUSIONS: The MO measurements used in this study were weakly correlated with lumbar spine and femoral BMDs, with no clear trends discernible in this population of postmenopausal women with no or mild periodontal disease.


Asunto(s)
Proceso Alveolar/diagnóstico por imagen , Densidad Ósea , Fémur/anatomía & histología , Vértebras Lumbares/anatomía & histología , Posmenopausia , Radiografía Dental Digital , Absorciometría de Fotón , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Mandíbula/diagnóstico por imagen , Maxilar/diagnóstico por imagen , Persona de Mediana Edad , Bolsa Periodontal/diagnóstico por imagen , Radiografía de Mordida Lateral , Estadística como Asunto
16.
J Periodontol ; 71(5): 683-9, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10872947

RESUMEN

BACKGROUND: Our objective was to test the association between cemento-enamel junction, alveolar-crest distance (CEJ-AC, as measured on digitized vertical bite-wing radiographs) and postcranial bone mineral density (BMD) relative to clinical, dietary, and demographic variables. METHODS: Data were collected in a cross-sectional study of 134 postmenopausal women. CEJ-AC distances were determined from digitized vertical bite-wing radiographs. Lumbar spine and proximal femur BMDs were determined from dual-energy x-ray absorptiometric scans. Correlation analysis and Student t tests were used to identify those variables most associated with CEJ-AC distance. The selected variables were modeled with a backward stepwise regression analysis, with CEJ-AC distance as the dependent variable. RESULTS: Parity (number of pregnancies to term), cigarette smoking, and the interaction of lateral spine BMD with cigarette smoking were independent predictors of CEJ-AC distance (P < or =0.05). Statistical models containing these variables accounted for 19% of the variation in CEJ-AC distances. CONCLUSIONS: CEJ-AC distance in postmenopausal women is the result of a complicated interaction of many effects, including but not limited to, parity, cigarette smoking, and skeletal BMD.


Asunto(s)
Pérdida de Hueso Alveolar/etiología , Pérdida de Hueso Alveolar/fisiopatología , Paridad/fisiología , Posmenopausia/fisiología , Fumar/efectos adversos , Absorciometría de Fotón , Factores de Edad , Pérdida de Hueso Alveolar/diagnóstico por imagen , Densidad Ósea/fisiología , Estudios Transversales , Dieta , Femenino , Humanos , Histerectomía , Análisis de los Mínimos Cuadrados , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/fisiología , Persona de Mediana Edad , Ovariectomía , Radiografía de Mordida Lateral , Análisis de Regresión , Factores de Riesgo , Cuello del Diente/diagnóstico por imagen , Cuello del Diente/fisiología
17.
Spine (Phila Pa 1976) ; 24(17): 1781-5, 1999 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-10488507

RESUMEN

STUDY DESIGN: A cross-sectional retrospective radiologic study. OBJECTIVES: To establish concordance rates between interpretations of computed tomography myelography and magnetic resonance imaging in patients with degenerative cervical spine disease. SUMMARY OF BACKGROUND DATA: Observed discrepancies in interpretation of computed tomography myelography and magnetic resonance imaging question the reliability of comparisons between these two methods. METHODS: This study blindly and randomly evaluated cervical computed tomography myelography and magnetic resonance imaging in 20 patients referred for clinically diagnosed cervical spondylotic radiculopathy, myelopathy, or both. The discovertebral joints, facet joints, lateral recesses, cord size, spinal canal, and neural foramina also were evaluated with graded scales. All results were subjected to the kappa statistic for strength of agreement. RESULTS: Agreement for interpretation of the discovertebral junction occurred in 144 of 240 sites (60%), indicating only moderately good intermethod concordance (kappa = 0.44). Intermethod agreement on the characterization of facet joint disease was only moderately good (143 of 160 sites; 89.4%; kappa = 0.52), and on characterization of lateral recess disease was poor (125 of 160 sites; 78.1%; kappa = 0.20). On degree of spinal canal compromise, there was agreement within one grade in 199 of 240 sites (82.9%; kappa = 0.42). Intermethod agreement on neural foraminal encroachment and cord size was only moderately good (kappa = 0.42 and 0.46, respectively). Computed tomography myelography tended to upgrade the spinal canal narrowing and neural foraminal encroachment. CONCLUSIONS: For most parameters of interpretation, the degree of concordance between computed tomography myelography and magnetic resonance imaging is only moderately good, with discrepancies noted especially in the differentiation of disc and bony pathology. These methods should be viewed as complementary studies.


Asunto(s)
Vértebras Cervicales , Imagen por Resonancia Magnética/métodos , Mielografía/métodos , Radiculopatía/diagnóstico , Compresión de la Médula Espinal/diagnóstico , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/patología , Estudios Transversales , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Osteofitosis Vertebral/diagnóstico
18.
Clin Neurol Neurosurg ; 99(4): 229-34, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9491294

RESUMEN

We reviewed the clinical records of 149 patients with pathologically proved cauda equina lesions in order to define the relative frequency and clinical presentations of the various diagnoses. The most common pathology was ependymomas (47 patients) followed in frequency by nerve sheath tumors (35 patients), metastases (27 patients), nonependymal glial neoplasms (six patients), meningiomas (six patients), lipomas (five patients), paragangliomas (five patients) and various other diagnoses (19 patients). Mean patient age at presentation for the various lesions included: metastases (51.5 years), nerve sheath tumors (49.7 years), nonependymal glial tumors (46.5 years), paragangliomas (41.2 years), ependymomas (38.3 years), meningiomas (34.7 years), and lipomas (18.4 years). ANOVA showed that the relationship between age and diagnosis for these groups to be statistically significant at a high level (P = 0.002). Low back pain was the most common symptom and occurred in 44 patients. Other symptoms included unilateral lower extremity pain or tenderness (24 patients), bilateral lower extremity pain or tenderness (16 patients), and bilateral lower extremity weakness (16 patients). No relationship between pathologic diagnosis and specific symptoms was found.


Asunto(s)
Cauda Equina/patología , Registros Médicos , Neoplasias de la Vaina del Nervio/epidemiología , Neoplasias del Sistema Nervioso Periférico/epidemiología , Academias e Institutos , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Dolor de la Región Lumbar/etiología , Masculino , Persona de Mediana Edad , Personal Militar , Metástasis de la Neoplasia , Neoplasias del Sistema Nervioso Periférico/complicaciones , Estudios Retrospectivos , Estados Unidos/epidemiología
19.
Plast Reconstr Surg ; 95(2): 277-83, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7824607

RESUMEN

Retrospective review of the records of 73 consecutive young children who underwent craniosynostosis surgery between 1978 and 1992 in one center was conducted to determine transfusion requirements, to document morbidity, and to identify causative variables associated with transfusion. Operative age and weight, affected suture(s), craniofacial surgeon, neurosurgeon, anesthesiologist, preoperative and postoperative hematocrit, and transfusion volumes of blood and crystalline products were recoded. Transfusion volumes were converted to percent estimated red cell mass for analysis. Affected sutures were unicoronal (22), sagittal (17), bicoronal (11), multiple (11), metopic (10), and lambdoid (2). Mean operative age was 6.4 months. Mean preoperative hematocrit was 34 percent. Eighty percent of patients were discharged with hematocrit of 29 percent or greater. Discharge hematocrit was unrelated to year of surgery. Mean intraoperative transfusion was 72.1 +/- 56.6 percent estimated red cell mass. Transfusions differed statistically among suture(s), neurosurgeons, and anesthesiologists. Extensive cranio-orbital surgery for synostosis in young children does not produce excessive hemorrhage or transfusion morbidity. The anesthesiologist and neurosurgeon may be equally or more important than the affected suture(s) as causal variables in transfusion.


Asunto(s)
Pérdida de Sangre Quirúrgica , Transfusión Sanguínea/estadística & datos numéricos , Craneosinostosis/cirugía , Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Preescolar , Hematócrito , Humanos , Lactante , Estudios Retrospectivos
20.
Plast Reconstr Surg ; 105(5): 1600-8, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10809087

RESUMEN

This study documents the pattern of unilateral cleft lip nasal reconstruction in the practice of one surgeon at a tertiary cleft center, evaluating the long-term appearance outcome of single-operation unilateral cleft lip nasal reconstruction in childhood. A retrospective medical record review was performed for all patients with a diagnosis of unilateral cleft lip and age greater than 15 years. Operative notes were reviewed, recording 15 variables identifying specific rhinoplastic maneuvers. Nasal appearance outcome analysis was performed for all patients who underwent only one nasal surgery before 12 years of age (n = 19). Standard frontal whole face photographic images were presented as opposing pairs in a looseleaf binder to two panels, 1 of 10 lay persons and 1 of 10 plastic surgeons. Each pair consisted of photographs of the same patient at different ages in one of three combinations: preoperative-perioperative, perioperative-longest postoperative, or preoperative-longest postoperative. Participants were asked to compare the appearance of the noses in the two photographs and assign a rating based on a 5-point Likert scale. Statistical analyses were performed on the data collected in the aesthetic analysis. The effect of surgery upon nasal appearance was assessed by comparing the preoperative and perioperative photographs. The effect of growth was assessed by comparing the perioperative and long-term postoperative photographs. The combined effect of surgery and growth was assessed by comparing the preoperative and long-term postoperative photographs. The data were assessed by lay and professional evaluators, together and separately, to determine whether differences existed. The majority of patients did not undergo revisional nasal surgery, whereas those who did usually had one nasal operation. Most revisional nasal surgery was performed in conjunction with other cleft-related secondary surgery. A majority of lay and professional evaluators perceived revisional nasal surgery as improving nasal appearance in the short-term and to a lesser degree in the long-term, as compared with the preoperative state. Evaluations of revisional nasal surgery are generally constant between the short-term and long-term postoperative images. Lay evaluations may be contaminated by a general decline in attractiveness with aging. Patient preference should be a major factor in the decision for nasal revision surgery. Multiple means of assessing nasal appearance outcome need to be used to validate results. Nasal appearance outcomes need to be correlated with outcomes with respect to nasal morphology and function as well as patient and parent satisfaction.


Asunto(s)
Labio Leporino/cirugía , Complicaciones Posoperatorias/etiología , Rinoplastia , Adolescente , Niño , Fisura del Paladar/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Satisfacción del Paciente , Complicaciones Posoperatorias/cirugía , Reoperación , Estudios Retrospectivos
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