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1.
J Digit Imaging ; 28(1): 53-61, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25037586

RESUMEN

In the era of health information exchanges, there are trade-offs to consider when sharing a patient's medical record among all providers that a patient might choose. Exchange among in-network partners on the same electronic medical records (EMR) and other integrated information systems is trivial. The patient identifier is common, as are the relevant departmental systems, to all providers. Difficulties arise when patient records including images (and reports) must be shared among different networks and even with the patients themselves. The National Institutes of Health (NIH) challenged Radiological Society of North America (RSNA) to develop a transport method that could supersede the need for physical media (for patients or other providers), replace point-to-point private networks among providers, and enable image exchange on an ad hoc basis between arbitrary health networks without long legal delays. In concert with the evolving US health care paradigm, patient engagement was to be fundamental. With Integrating Healthcare Enterprise's (IHE's) help, the challenge has been met with an operational system.


Asunto(s)
Redes de Comunicación de Computadores , Registros Electrónicos de Salud , Difusión de la Información/métodos , Radiología , Integración de Sistemas , Humanos , América del Norte , Sociedades Médicas
2.
J Imaging Inform Med ; 37(3): 1228-1238, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38366293

RESUMEN

We evaluated the impact of training set size on generative adversarial networks (GANs) to synthesize brain MRI sequences. We compared three sets of GANs trained to generate pre-contrast T1 (gT1) from post-contrast T1 and FLAIR (gFLAIR) from T2. The baseline models were trained on 135 cases; for this study, we used the same model architecture but a larger cohort of 1251 cases and two stopping rules, an early checkpoint (early models) and one after 50 epochs (late models). We tested all models on an independent dataset of 485 newly diagnosed gliomas. We compared the generated MRIs with the original ones using the structural similarity index (SSI) and mean squared error (MSE). We simulated scenarios where either the original T1, FLAIR, or both were missing and used their synthesized version as inputs for a segmentation model with the original post-contrast T1 and T2. We compared the segmentations using the dice similarity coefficient (DSC) for the contrast-enhancing area, non-enhancing area, and the whole lesion. For the baseline, early, and late models on the test set, for the gT1, median SSI was .957, .918, and .947; median MSE was .006, .014, and .008. For the gFLAIR, median SSI was .924, .908, and .915; median MSE was .016, .016, and .019. The range DSC was .625-.955, .420-.952, and .610-.954. Overall, GANs trained on a relatively small cohort performed similarly to those trained on a cohort ten times larger, making them a viable option for rare diseases or institutions with limited resources.


Asunto(s)
Neoplasias Encefálicas , Encéfalo , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Glioma/diagnóstico por imagen , Glioma/patología , Redes Neurales de la Computación , Interpretación de Imagen Asistida por Computador/métodos
3.
Curr Top Microbiol Immunol ; 318: 73-92, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18219815

RESUMEN

Remyelination of axons that have been demyelinated due to multiple sclerosis (MS) may be a critical step in restoring the damaged axons and reversing the disease process. While it is possible to establish the presence of remyelination with microscopy of tissue samples, it is important to have noninvasive or minimally invasive methods to measure remyelination in living animals and humans. Such tools are critical to establishing the efficacy of agents purported to promote or enhance remyelination. This chapter reviews the technology of imaging of the brain, its application to MS, and the current state of imaging techniques for measuring remyelination and the health of the associated neurons in the setting of MS.


Asunto(s)
Encéfalo/diagnóstico por imagen , Esclerosis Múltiple/diagnóstico por imagen , Vaina de Mielina/diagnóstico por imagen , Neuronas/diagnóstico por imagen , Animales , Humanos , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Vaina de Mielina/fisiología , Neuronas/fisiología , Radiografía , Cintigrafía
4.
Brain ; 131(Pt 7): 1759-75, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18535080

RESUMEN

Atypical imaging features of multiple sclerosis lesions include size >2 cm, mass effect, oedema and/or ring enhancement. This constellation is often referred to as 'tumefactive multiple sclerosis'. Previous series emphasize their unifocal and clinically isolated nature, however, evolution of these lesions is not well defined. Biopsy may be required for diagnosis. We describe clinical and radiographic features in 168 patients with biopsy confirmed CNS inflammatory demyelinating disease (IDD). Lesions were analysed on pre- and post-biopsy magnetic resonance imaging (MRI) for location, size, mass effect/oedema, enhancement, multifocality and fulfilment of Barkhof criteria. Clinical data were correlated to MRI. Female to male ratio was 1.2 : 1, median age at onset, 37 years, duration between symptom onset and biopsy, 7.1 weeks and total disease duration, 3.9 years. Clinical course prior to biopsy was a first neurological event in 61%, relapsing-remitting in 29% and progressive in 4%. Presentations were typically polysymptomatic, with motor, cognitive and sensory symptoms predominating. Aphasia, agnosia, seizures and visual field defects were observed. At follow-up, 70% developed definite multiple sclerosis, and 14% had an isolated demyelinating syndrome. Median time to second attack was 4.8 years, and median EDSS at follow-up was 3.0. Multiple lesions were present in 70% on pre-biopsy MRI, and in 83% by last MRI, with Barkhof criteria fulfilled in 46% prior to biopsy and 55% by follow-up. Only 17% of cases remained unifocal. Median largest lesion size on T2-weighted images was 4 cm (range 0.5-12), with a discernible size of 2.1 cm (range 0.5-7.5). Biopsied lesions demonstrated mass effect in 45% and oedema in 77%. A strong association was found between lesion size, and presence of mass effect and/or oedema (P < 0.001). Ring enhancement was frequent. Most tumefactive features did not correlate with gender, course or diagnosis. Although lesion size >5 cm was associated with a slightly higher EDSS at last follow-up, long-term prognosis in patients with disease duration >10 years was better (EDSS 1.5) compared with a population-based multiple sclerosis cohort matched for disease duration (EDSS 3.5; P < 0.001). Given the retrospective nature of the study, the precise reason for biopsy could not always be determined. This study underscores the diagnostically challenging nature of CNS IDDs that present with atypical clinical or radiographic features. Most have multifocal disease at onset, and develop RRMS by follow-up. Although increased awareness of this broad spectrum may obviate need for biopsy in many circumstances, an important role for diagnostic brain biopsy may be required in some cases.


Asunto(s)
Esclerosis Múltiple/diagnóstico , Adolescente , Adulto , Anciano , Biopsia , Encéfalo/patología , Edema Encefálico/etiología , Edema Encefálico/patología , Niño , Progresión de la Enfermedad , Métodos Epidemiológicos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/patología
5.
Bone Joint J ; 101-B(1): 63-67, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30601051

RESUMEN

AIMS: The number of rotator cuff repairs that are undertaken is increasing. Reverse shoulder arthroplasty (RSA) is the procedure of choice for patients with rotator cuff arthropathy. We sought to determine whether patients who underwent rotator cuff repair and subsequent RSA had different outcomes compared with a matched control group who underwent RSA without a previous rotator cuff repair. PATIENTS AND METHODS: All patients with a history of rotator cuff repair who underwent RSA between 2000 and 2015 with a minimum follow-up of two years were eligible for inclusion as the study group. Outcomes, including the American Shoulder and Elbow Surgeons (ASES) scores, were compared with a matched control group of patients who underwent RSA without having previously undergone rotator cuff repair. RESULTS: The study group included 45 patients. Their mean age was 69 years (sd 8.6) and 27 patients (60%) were women. The mean ASES score improved from 43.1 to 76.6 two years postoperatively, and to 66.9 five years postoperatively. There was no significant difference between the outcomes at two years in the two groups (all p ≥ 0.05), although there was significantly more improvement in ASES scores in the control group (44.5 vs 33.4; p = 0.01). However, there was no significant difference between ASES scores at two and five years when baseline ASES scores were matched in the two groups (p = 0.42 at two years; p = 0.35 at five years). CONCLUSION: Significant improvements in ASES scores were seen following RSA in patients who had previously undergone rotator cuff repair. They had higher baseline ASES scores than those who had not previously undergone this surgery. However, there was no significant difference in outcomes between the two groups, two years postoperatively. Previous rotator cuff repair does not appear to affect the early outcome after RSA adversely.


Asunto(s)
Artroplastía de Reemplazo de Hombro , Lesiones del Manguito de los Rotadores/cirugía , Anciano , Femenino , Humanos , Masculino , Dimensión del Dolor , Dolor Postoperatorio/etiología , Satisfacción del Paciente , Reoperación/estadística & datos numéricos , Lesiones del Manguito de los Rotadores/psicología , Resultado del Tratamiento
6.
Musculoskelet Surg ; 101(3): 213-218, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28255840

RESUMEN

PURPOSE: Intertrochanteric hip fracture is a common injury in the Medicare population. Very little is known about the in-hospital mortality risk of intertrochanteric hip fractures and associated demographics for the US Medicare population. The purpose of this study is to determine the in-hospital mortality rate of closed intertrochanteric hip fractures and to evaluate demographic factors influencing an increased mortality risk. METHODS: The PearlDiver Medicare database from 2005 to 2010 was queried for closed intertrochanteric hip fractures. Stratified sampling was conducted by creating subset for individuals with a death discharge from inpatient facilities. Statistical analysis was performed where appropriate. RESULTS: Throughout 2005-2010 there were a total of 1,138,142 intertrochanteric hip fractures. There were 19,385 deaths during the initial hospital stay, yielding a mortality rate of 1.70%. There was a 1.83% mortality rate for patients 75 and older and patients over the age of 84 comprised the majority of deaths at 58%. The mortality rate was lower for females (1.39%) than for males (2.56%) (p < 0.0002). CONCLUSION: We found in the Medicare database that there is a relatively low rate of in-hospitality mortality associated with intertrochanteric hip fractures; this rate is lower than previously reported. We report a 1.70% in-hospital mortality using a complete Medicare dataset. Based on previous reporting for short term and one-year mortality risk, the present study suggests that mortality risk is greatest after patients have been released from the hospital. More attention should be paid to understanding and attenuating the mortality associated with intertrochanteric hip fractures after the acute hospital phase.


Asunto(s)
Fracturas de Cadera/mortalidad , Mortalidad Hospitalaria , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Fracturas Cerradas/mortalidad , Humanos , Masculino , Medicare/estadística & datos numéricos , Riesgo , Factores Sexuales , Estados Unidos/epidemiología
7.
Bone Joint J ; 99-B(7): 934-938, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28663400

RESUMEN

AIMS: The aim of the present study was to compare the 30- and 90-day re-admission rates and complication rates of outpatient and inpatient total shoulder arthroplasty (TSA). PATIENTS AND METHODS: The United States Medicare Standard Analytical Files database was questioned to identify patients who had undergone outpatient or inpatient TSA between 2005 and 2012. Patient characteristics were compared between the two groups using chi-squared analysis. Multivariate logistic regression analysis was used to control for differences in baseline patient characteristics and to compare the two groups in terms of post-operative complications within 90 days and re-admission within 30 days and 90 days. RESULTS: A total of 123 347 Medicare subscribers underwent TSA between 2005 and 2012; 3493 (2.8%) had the procedure performed as an outpatient. A significantly greater proportion of patients who underwent TSA as inpatients were women, had a history of smoking, and had a greater incidence of medical comorbidity including diabetes, coronary artery disease, congestive heart failure, and chronic kidney disease (p < 0.05 for all). Re-admission rates were significantly higher for inpatients at both 30 days (0.83% versus 0.60%, p = 0.016, odds ratio 1.8) and 90 days (2.87% versus 2.04%, p < 0.001, odds ratio 1.8). Complications, including thromboembolic events (p < 0.001) and surgical site infection (p = 0.002), were significantly higher in inpatients. CONCLUSION: Patients who underwent TSA on an outpatient basis were overall younger and healthier than those who had inpatient surgery, which suggests that patient selection was taking place. After controlling for age, gender, and medical conditions, patients who underwent TSA as outpatients had lower rates of 30- and 90-day re-admission and a lower rate of complications than inpatients. Cite this article: Bone Joint J 2017;99-B:934-8.


Asunto(s)
Artroplastía de Reemplazo de Hombro , Evaluación de Resultado en la Atención de Salud , Readmisión del Paciente/estadística & datos numéricos , Factores de Edad , Anciano , Anciano de 80 o más Años , Comorbilidad , Femenino , Humanos , Pacientes Internos , Masculino , Medicare , Persona de Mediana Edad , Pacientes Ambulatorios , Complicaciones Posoperatorias/epidemiología , Rango del Movimiento Articular , Factores de Riesgo , Estados Unidos/epidemiología
8.
Yearb Med Inform ; Suppl 1: S23-31, 2016 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-27362590

RESUMEN

The science and applications of informatics in medical imaging have advanced dramatically in the past 25 years. This article provides a selective overview of key developments in medical imaging informatics. Advances in standards and technologies for compression and transmission of digital images have enabled Picture Archiving and Communications Systems (PACS) and teleradiology. Research in speech recognition, structured reporting, ontologies, and natural language processing has improved the ability to generate and analyze the reports of imaging procedures. Informatics has provided tools to address workflow and ergonomic issues engendered by the growing volume of medical image information. Research in computeraided detection and diagnosis of abnormalities in medical images has opened new avenues to improve patient care. The growing number of medical-imaging examinations and their large volumes of information create a natural platform for "big data" analytics, particularly when joined with high-dimensional genomic data. Radiogenomics investigates relationships between a disease's genetic and gene-expression characteristics and its imaging phenotype; this emerging field promises to help us better understand disease biology, prognosis, and treatment options. The next 25 years offer remarkable opportunities for informatics and medical imaging together to lead to further advances in both disciplines and to improve health.


Asunto(s)
Diagnóstico por Imagen/tendencias , Informática Médica/tendencias , Diagnóstico por Imagen/normas , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Informática Médica/historia , Informática Médica/normas , Sistemas de Información Radiológica/tendencias , Integración de Sistemas
9.
J Orthop Surg (Hong Kong) ; 24(2): 222-7, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27574267

RESUMEN

PURPOSE: To review the outcome of 12 patients who underwent debridement and injection of bioceramic for unicameral bone cyst (UBC). The resorption rate of the bioceramic was estimated by both traditional and novel methods. METHODS: Records of 10 males and 2 females aged 6 to 34 years who underwent debridement and injection of bioceramic for UBC and were followed up for a mean of 41 (range, 26-57) months were reviewed. Functional outcome was assessed using the selfcompleted Musculoskeletal Tumor Society (MSTS) questionnaire. Radiological outcome was assessed using both original and modified Neer Outcome Rating System. The resorption rate of the bioceramic was estimated using both traditional and novel (ImageJ) methods. RESULTS: The mean MSTS score was 29.7 (range, 28-30) indicating excellent functional outcome. Of the 12 patients, 9 achieved complete healing and 3 had a residual cyst of 1%, 11%, and 52%. The last was considered a local recurrence, and the patient underwent repeat percutaneous injection of the bioceramic 1.5 years later and remained disease-free 4 years later. The mean resorption rate was 29% faster when estimated using the traditional rather than the ImageJ method (0.47 vs. 0.33 cm3/day, p=0.02). In the patient with recurrence, the resorption rate was faster than the average (0.68 vs. 0.33 cm3/day). CONCLUSION: A single percutaneous injection of the bioceramic for UBC achieved good functional and radiological outcome while avoiding donor-site morbidity.


Asunto(s)
Quistes Óseos/cirugía , Sustitutos de Huesos/administración & dosificación , Trasplante Óseo , Adolescente , Adulto , Materiales Biocompatibles , Cerámica , Niño , Desbridamiento , Femenino , Humanos , Inyecciones , Masculino , Adulto Joven
10.
Musculoskelet Surg ; 100(3): 157-163, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27628911

RESUMEN

PURPOSE: The purpose was to perform a systematic review of the literature investigating biomechanical studies of ulnar collateral ligament reconstruction (UCLR) techniques to summarize the most commonly analyzed methods of fixation (at both the ulna and humerus), the degree of elbow flexion at the time of fixation, graft characteristics, and modes of failure with these techniques. MATERIALS AND METHODS: A systematic review was performed. All cadaveric biomechanical studies that tested a reconstruction method for UCLR were included. Descriptive statistics were calculated for each study and parameter/variable analyzed. RESULTS: Twenty-three studies were included with a total of 397 elbows in 242 cadavers (mean age 54.8 ± 20 years, range 16-96). The majority of studies (65 %) used a palmaris longus graft. The docking technique (37.2 %) was the most commonly tested reconstruction method. Significant heterogeneity between studies precluded assimilation of specific techniques (each of the 23 studies utilized a unique technique). Fixation was performed at 30°-90° of elbow flexion. The most common mode of failure was suture failure (51 %), followed by midsubstance rupture (27.00 %), and bone tunnel fracture (14.00 %). No significant differences were observed amongst techniques for all measures analyzed. CONCLUSION: This study found the docking technique to be the most commonly tested technique, while the mode of reconstruction failure was most commonly at the suture interface. If the graft failed at the bone interface, it was most likely to occur at the ulna. Surgeon preference and comfort level with a specific technique should dictate choice.


Asunto(s)
Fenómenos Biomecánicos , Ligamento Colateral Cubital/cirugía , Procedimientos de Cirugía Plástica , Cadáver , Articulación del Codo/cirugía , Humanos , Procedimientos Ortopédicos/métodos , Rango del Movimiento Articular , Procedimientos de Cirugía Plástica/métodos , Factores de Riesgo , Rotura/cirugía , Trasplantes
11.
AJNR Am J Neuroradiol ; 36(12): 2242-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26359151

RESUMEN

BACKGROUND AND PURPOSE: Relative cerebral blood volume, as measured by T2*-weighted dynamic susceptibility-weighted contrast-enhanced MRI, represents the most robust and widely used perfusion MR imaging metric in neuro-oncology. Our aim was to determine whether differences in modeling implementation will impact the correction of leakage effects (from blood-brain barrier disruption) and the accuracy of relative CBV calculations as measured on T2*-weighted dynamic susceptibility-weighted contrast-enhanced MR imaging at 3T field strength. MATERIALS AND METHODS: This study included 52 patients with glioma undergoing DSC MR imaging. Thirty-six patients underwent both non-preload dose- and preload dose-corrected DSC acquisitions, with 16 patients undergoing preload dose-corrected acquisitions only. For each acquisition, we generated 2 sets of relative CBV metrics by using 2 separate, widely published, FDA-approved commercial software packages: IB Neuro and nordicICE. We calculated 4 relative CBV metrics within tumor volumes: mean relative CBV, mode relative CBV, percentage of voxels with relative CBV > 1.75, and percentage of voxels with relative CBV > 1.0 (fractional tumor burden). We determined Pearson (r) and Spearman (ρ) correlations between non-preload dose- and preload dose-corrected metrics. In a subset of patients with recurrent glioblastoma (n = 25), we determined receiver operating characteristic area under the curve for fractional tumor burden accuracy to predict the tissue diagnosis of tumor recurrence versus posttreatment effect. We also determined correlations between rCBV and microvessel area from stereotactic biopsies (n = 29) in 12 patients. RESULTS: With IB Neuro, relative CBV metrics correlated highly between non-preload dose- and preload dose-corrected conditions for fractional tumor burden (r = 0.96, ρ = 0.94), percentage > 1.75 (r = 0.93, ρ = 0.91), mean (r = 0.87, ρ = 0.86), and mode (r = 0.78, ρ = 0.76). These correlations dropped substantially with nordicICE. With fractional tumor burden, IB Neuro was more accurate than nordicICE in diagnosing tumor versus posttreatment effect (area under the curve = 0.85 versus 0.67) (P < .01). The highest relative CBV-microvessel area correlations required preload dose and IB Neuro (r = 0.64, ρ = 0.58, P = .001). CONCLUSIONS: Different implementations of perfusion MR imaging software modeling can impact the accuracy of leakage correction, relative CBV calculation, and correlations with histologic benchmarks.


Asunto(s)
Neoplasias Encefálicas/irrigación sanguínea , Glioma/irrigación sanguínea , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Modelos Neurológicos , Adulto , Anciano , Neoplasias Encefálicas/patología , Circulación Cerebrovascular/fisiología , Femenino , Glioma/patología , Humanos , Masculino , Persona de Mediana Edad , Perfusión , Programas Informáticos
12.
Neurology ; 51(5): 1342-52, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9818858

RESUMEN

OBJECTIVE: To determine whether sulfasalazine is better than placebo in slowing disability progression in MS. METHODS: In this randomized, double-blind, placebo-controlled phase III trial, 199 patients with active relapsing-remitting (n = 151) or progressive (n = 48) MS were evaluated at 3-month intervals for a minimum of 3 years (94% completed 3 years of follow-up; mean follow-up, 3.7 years). MRI studies were performed at 6-month intervals on a subset of 89 patients. RESULTS: Sulfasalazine failed to slow or prevent disability progression as measured by the primary outcome (confirmed worsening of the Expanded Disability Status Scale [EDSS] score by at least 1.0 point on two consecutive 3-month visits). Sulfasalazine influenced favorably a number of secondary outcomes during the first 18 months of the trial (e.g., annualized relapse rate, proportion of relapse-free patients; progressive subgroup only: rate of EDSS progression at 1 and 2 years, median time to EDSS progression) but these positive findings were not sustained into the second half of the trial. CONCLUSIONS: Sulfasalazine does not prevent EDSS score progression in the subset of MS patients studied by this protocol. Treatments may improve relapse-related outcomes in MS, at least temporarily, without providing sustained slowing of EDSS progression. Phase III MS trials should be of sufficient length to determine a meaningful impact on disease course.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Sulfasalazina/uso terapéutico , Adulto , Encéfalo/patología , Canadá , Personas con Discapacidad , Progresión de la Enfermedad , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Minnesota , Esclerosis Múltiple/fisiopatología , Placebos , Recurrencia , Análisis de Supervivencia , Factores de Tiempo
13.
Neurology ; 55(8): 1135-43, 2000 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-11071491

RESUMEN

BACKGROUND: Immunoglobulin (Ig) administration induces remyelination in the Theiler's virus model of MS. METHODS: A randomized, double-blinded, placebo-controlled trial of IV immunoglobulin (IVIg) was performed in patients with MS who had persistent muscle weakness that had been stable for between 4 and 18 months to determine whether this would improve muscle strength (primary outcome: isometric muscle strength). Patients received either IVIg (0.4 g/kg) or placebo daily for 5 days, then single infusions every 2 weeks for 3 months (total, 11 infusions). Muscle groups identified by clinical measures to have unchanging significant weakness were the major targets for therapeutic response (targeted neurologic deficit [TND]). RESULTS: IVIg was well tolerated. An interim analysis after 67 patients were enrolled indicated no difference in the degree of change in strength between treatment groups in either the TND or non-TND muscle groups at 6 months, and the trial was terminated. There was no apparent benefit in relapse behavior or impairment measures during the 6-month observation period. Nor was there apparent benefit in either patients who remained clinically stable or in those with evidence of disease activity. Patients with active MS during the trial worsened in both TND and non-TND muscle groups. This worsening was seen regardless of whether the clinical manifestations of disease activity involved the TND muscle groups. CONCLUSIONS: IVIg does not reverse established weakness in MS. Measurements of isometric muscle strength were reliable (reproducible) indices of strength and may be sensitive, objective methods to document functional changes in impairment in future MS trials.


Asunto(s)
Inmunoglobulinas Intravenosas/uso terapéutico , Distrofias Musculares/tratamiento farmacológico , Adulto , Método Doble Ciego , Femenino , Humanos , Inmunoglobulinas Intravenosas/administración & dosificación , Contracción Isométrica/efectos de los fármacos , Contracción Isométrica/fisiología , Masculino , Persona de Mediana Edad , Músculos/efectos de los fármacos , Músculos/fisiopatología , Distrofias Musculares/fisiopatología , Pronóstico
14.
Mayo Clin Proc ; 72(11): 1080-9, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9374985

RESUMEN

Magnetic resonance imaging (MRI) has become an important technique for monitoring the effectiveness of putative treatments for multiple sclerosis (MS) because of its high sensitivity, objectivity, and noninvasive nature. Its importance as a surrogate measure of disease, however, is an issue that is more difficult to validate than might seem to be the case. In this review, we describe the role of MRI in the assessment of putative therapies for MS. New magnetic resonance techniques and methods of image analyses aimed at better demonstrating the nature and extent of disease are discussed, and the role of MRI in published MS therapeutic trials is examined. MRI is a frequently used secondary outcome measure for putative treatment strategies for MS. Although it is sensitive to changes in the inflammatory component of the MS disease process, poor correlation has been noted between MRI findings and long-term patient outcome. There is a widespread expectation that new magnetic resonance techniques--such as fluid-attenuated inversion recovery, magnetization transfer imaging, and magnetic resonance spectroscopy--will ultimately be useful for characterization of pathologic changes within the MS lesion and more generally of the MS disease process. Whether magnetic resonance changes seen in experimental therapies predict the long-term clinical course of the disease remains to be determined.


Asunto(s)
Imagen por Resonancia Magnética , Esclerosis Múltiple/diagnóstico , Ensayos Clínicos como Asunto , Humanos , Esclerosis Múltiple/terapia , Valor Predictivo de las Pruebas , Resultado del Tratamiento
15.
Mayo Clin Proc ; 74(7): 661-70, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10405694

RESUMEN

OBJECTIVE: To assess the advantages and disadvantages of an endoscopic transnasal approach to pituitary surgery for a select group of clinically nonfunctioning macroadenomas and to compare results of this approach with the sublabial transseptal approach at a single institution. PATIENTS AND METHODS: We retrospectively reviewed the records of 26 patients with clinically nonfunctioning pituitary macroadenomas approached endoscopically and 44 matched control patients with the same tumors approached sublabially between January 1, 1995, and October 31, 1997. RESULTS: At baseline, the groups were not significantly different for age, sex distribution, number of comorbid conditions, visual field defects, degree of anterior pituitary insufficiency, or preoperative assessment of tumor volume or invasiveness. Mean (SD) operative times were significantly reduced in the endoscopic group vs the sublabial group: 2.7 (0.7) hours vs 3.4 (0.9) hours (P < .001). Postoperative assessment of surgical resection and postoperative alterations of anterior pituitary function or visual fields were not significantly different between groups, and complication rates were similar in both groups. CONCLUSION: This endoscopic transnasal approach to pituitary resection results in significantly shorter operative time without compromising the extent of tumor resection. The distinct disadvantage of this approach is an off-center view of the sella and a diminished working channel to the sella turcica. For these reasons, the endoscopic approach or its variation is an alternative to the sublabial approach but should be considered only by experienced pituitary neurosurgeons.


Asunto(s)
Adenoma/cirugía , Endoscopía/métodos , Neoplasias Hipofisarias/cirugía , Adenoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Labio/cirugía , Masculino , Registros Médicos , Persona de Mediana Edad , Estadificación de Neoplasias , Nariz/cirugía , Neoplasias Hipofisarias/patología , Estudios Retrospectivos , Resultado del Tratamiento
16.
AJNR Am J Neuroradiol ; 14(3): 713-20, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8517364

RESUMEN

PURPOSE: To describe our approach to mapping the functional information provided by single photon emission computed tomography (SPECT) onto the anatomic template provided by MR, and to determine both the number of markers required to achieve accuracy and the impact of voxel shape on accuracy. METHODS: Point-to-point iterative minimization using externally fixed fiducial markers was involved and computer simulations were performed. Two types of validation studies were performed using a phanton using a phantom of known dimensions. First, the spatial distortion that may be present in MR was investigated for spin-echo and gradient-recalled echo images. Next, the accuracy with which the SPECT image could be transformed to match the MR template was analyzed. The method is also demonstrated in four cases of patients with epilepsy. RESULTS: Computer simulations indicated that for voxel dimensions we expected to use, eight fiduciary markers would consistently produce acceptable accuracy. Simulations also showed that more isotropic voxels would be more accurate if voxel volume is held constant. The spatial accuracy of both spin-echo and gradient-recalled echo images of a phantom was accurate to within 3 mm. When the SPECT image of the same phantom was correlated with the MR image using this technique, internal marker errors were never greater than 3 mm, and the mean error was 2.2 mm. CONCLUSIONS: Images from different modalities can be accurately correlated using multiple fiduciary markers. SPECT and MR images of the given dimensions can be correlated to within 3 mm. The technique aids in clarification of the nature of SPECT perfusion abnormalities and in their anatomic localization.


Asunto(s)
Imagen por Resonancia Magnética , Tomografía Computarizada de Emisión de Fotón Único , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Niño , Epilepsia/diagnóstico , Epilepsia/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Estructurales
17.
Diabetes Technol Ther ; 3(1): 81-90, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11469711

RESUMEN

Alternative methods for self-monitoring of blood glucose have been pursued by many researchers, largely in response to evidence gathered in several long-term studies of patients with diabetes mellitus. These studies suggest that long-term complications of the disease may be mitigated if the disease is intensively managed, a component of which is increased monitoring. Many of the alternative methods utilize interstitial fluid (ISF) as the diagnostic fluid, rather than finger blood. A time lag in the distribution of glucose from blood to the interstitium has been observed by many, with estimates of lag time varying from none to 45 min. Dermal ISF was sampled from diabetic subjects in two tests and compared to finger blood glucose. In the first test, data were collected over time in a manner that allowed a cross-correlation analysis to predict an average lag time. Information from this test was then used as input to a data collection format for a method comparison test of 691 patients with diabetes in which ISF data were collected immediately after the finger blood reference and 15 min after the reference. An average lag time of about 25 min was determined from the cross-correlation analysis, with the correlation error reduced by three-fourths within a 15-min lag time. In the method comparison test, the correlation coefficient between finger blood glucose and ISF glucose improved from 0.923 to 0.951, and the percentage of data in the A zone of the Clarke Error Grid rose from 80.2% to 90.6% for the ISF glucose data collected at no lag and 15-min lag, respectively. Dermal ISF glucose measurement might be a reasonable alternative to blood glucose measurement for patients routinely monitoring ambient glycemia, although more testing in the sensitive hypoglycemic range is needed to clarify what might happen in cases of rapidly changing glucose.


Asunto(s)
Glucemia/análisis , Diabetes Mellitus/sangre , Espacio Extracelular/química , Dedos/irrigación sanguínea , Glucosa/análisis , Recolección de Muestras de Sangre/instrumentación , Recolección de Muestras de Sangre/métodos , Capilares , Diseño de Equipo , Humanos , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Valores de Referencia , Análisis de Regresión , Reproducibilidad de los Resultados , Manejo de Especímenes/instrumentación , Manejo de Especímenes/métodos
18.
Thyroid ; 11(3): 221-6, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11327612

RESUMEN

Graves' ophthalmopathy (GO) is an autoimmune disease characterized by an increase in the volume of the orbital fatty/connective tissues and extraocular muscles. This volume change is due to expansion of the adipose tissues and to accumulation of glycosaminoglycans and edema within the connective tissues of the orbit. We have shown previously that a subpopulation of confluent human orbital preadipocyte fibroblasts can be induced in vitro to differentiate into cells with morphological features of adipocytes and that these cultures express functional thyrotropin receptor (TSHR). In order to identify and study these cells further, we examined the expression of leptin protein and TSHR and leptin mRNA in these cultures. Using immunocytochemistry with objective measurement of immunofluorescent staining intensity on digitized microscopic images, we determined leptin protein expression to be 6 to 37 times greater in differentiated cultures than in control cultures. In addition, we showed that the expression of both genes is enhanced in differentiated cultures. We suggest that an unknown humoral stimulus, present in Graves' disease, might act to induce the differentiation of normal orbital fibroblasts into TSHR-bearing adipocytes. This process would be expected to result in expansion of the orbital adipose tissues and increased TSHR expression within the orbit.


Asunto(s)
Adipocitos/metabolismo , Fibroblastos/metabolismo , Expresión Génica , Enfermedad de Graves/patología , Leptina/genética , Órbita/patología , Diferenciación Celular , Células Cultivadas , Técnica del Anticuerpo Fluorescente , Enfermedad de Graves/metabolismo , Humanos , ARN Mensajero/análisis , Receptores de Leptina , Receptores de Tirotropina/genética , Células Madre/metabolismo
19.
Gen Hosp Psychiatry ; 15(5): 307-15, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8307344

RESUMEN

The availability of short-stay beds for brief admissions to a Psychiatric Emergency Service (PES) is a model that meets a variety of patient and system needs, allowing time to develop alternatives to hospitalization or gain diagnostic clarity, serving a respite function, providing a hospital setting that does not gratify dependency needs, and relieving inpatient census pressures. An eight-bed service for brief inpatient stays of up to 3 days was developed on a PES which serves a large nine-country catchment area in northeastern New York State. Admissions to this unit would otherwise have gone to a medical school teaching hospital psychiatric unit or a state psychiatric center. Fifty-one consecutive admissions were studied. The majority of patients were dischargeable in the short time frame and did not require transfer for longer-term care. The patients as a group showed improvement in psychiatric symptomatology and rated high satisfaction with the program. Most patients were diagnosed with schizophrenia or personality disorder (PD). Suicidality and substance abuse were frequent. The PD patients had a strong association with suicidality and some association with substance abuse, whereas the schizophrenics had more psychiatric symptomatology. PD patients were more likely to be discharged, leading us to propose a rationale for why this group may be uniquely suited to this approach. The study was replicated after a year on another sample of 51 consecutive admissions, confirming the earlier results and providing a 1-year follow-up on the program.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Intervención en la Crisis (Psiquiatría) , Servicios de Urgencia Psiquiátrica , Trastornos Mentales/terapia , Admisión del Paciente/estadística & datos numéricos , Adolescente , Adulto , Anciano , Estudios Transversales , Servicios de Urgencia Psiquiátrica/estadística & datos numéricos , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Tiempo de Internación/estadística & datos numéricos , Masculino , Trastornos Mentales/epidemiología , Persona de Mediana Edad , New York/epidemiología , Readmisión del Paciente/estadística & datos numéricos , Satisfacción del Paciente , Trastornos de la Personalidad/epidemiología , Trastornos de la Personalidad/terapia , Derivación y Consulta/estadística & datos numéricos , Esquizofrenia/epidemiología , Esquizofrenia/terapia , Psicología del Esquizofrénico , Resultado del Tratamiento , Revisión de Utilización de Recursos
20.
Gen Hosp Psychiatry ; 20(1): 44-7, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9506253

RESUMEN

This study describes "County Drift," the tendency of chronic psychiatric patients to move from outlying counties to the central county containing the psychiatric hospital. Changes of residence of repeat visitors to a Psychiatric Emergency Service were examined to substantiate that a higher proportion (34.2%) moved to the central county than the reverse (5.3%). An analysis comparing patients who moved to the central county with those who did not showed that patients already connected to treatment and with schizophrenic/psychotic, disorders remained in their home counties. Patients presenting complications reflected by secondary diagnoses of personality or substance use disorders were more likely to relocate to the area of the psychiatric facility.


Asunto(s)
Servicios de Urgencia Psiquiátrica/estadística & datos numéricos , Trastornos Mentales/epidemiología , Readmisión del Paciente/estadística & datos numéricos , Dinámica Poblacional , Adulto , Anciano , Enfermedad Crónica , Femenino , Mal Uso de los Servicios de Salud/estadística & datos numéricos , Humanos , Masculino , Área sin Atención Médica , Trastornos Mentales/psicología , Trastornos Mentales/rehabilitación , Persona de Mediana Edad , New York/epidemiología , Trastornos Psicóticos/epidemiología , Trastornos Psicóticos/psicología , Trastornos Psicóticos/rehabilitación , Esquizofrenia/epidemiología , Esquizofrenia/rehabilitación , Psicología del Esquizofrénico
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