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1.
BMC Med Res Methodol ; 23(1): 21, 2023 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-36681808

RESUMEN

BACKGROUND: Patient-reported physical function (PF) is a key endpoint in cancer clinical trials. Using complex statistical methods, common metrics have been developed to compare scores from different patient-reported outcome (PRO) measures, but such methods do not account for possible differences in questionnaire content. Therefore, the aim of our study was a content comparison of frequently used PRO measures for PF in cancer patients. METHODS: Relying on the framework of the International Classification of Functioning, Disability and Health (ICF) we categorized the item content of the physical domains of the following measures: EORTC CAT Core, EORTC QLQ-C30, SF-36, PROMIS Cancer Item Bank for Physical Function, PROMIS Short Form for Physical Function 20a, and the FACT-G. Item content was linked to ICF categories by two independent reviewers. RESULTS: The 118 items investigated were assigned to 3 components ('d - Activities and Participation', 'b - Body Functions', and 'e - Environmental Factors') and 11 first-level ICF categories. All PF items of the EORTC measures but one were assigned to the first-level ICF categories 'd4 - Mobility' and 'd5 - Self-care', all within the component 'd - Activities and Participation'. The SF-36 additionally included item content related to 'd9 - Community, social and civic life' and the PROMIS Short Form for Physical Function 20a also included content related to 'd6 - domestic life'. The PROMIS Cancer Item Bank (v1.1) covered, in addition, two first-level categories within the component 'b - Body Functions'. The FACT-G Physical Well-being scale was found to be the most diverse scale with item content partly not covered by the ICF framework. DISCUSSION: Our results provide information about conceptual differences between common PRO measures for the assessment of PF in cancer patients. Our results complement quantitative information on psychometric characteristics of these measures and provide a better understanding of the possibilities of establishing common metrics.


Asunto(s)
Personas con Discapacidad , Neoplasias , Humanos , Clasificación Internacional del Funcionamiento, de la Discapacidad y de la Salud , Medición de Resultados Informados por el Paciente , Encuestas y Cuestionarios , Neoplasias/terapia , Evaluación de la Discapacidad , Actividades Cotidianas , Calidad de Vida
2.
Knee Surg Sports Traumatol Arthrosc ; 28(3): 952-959, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31267191

RESUMEN

PURPOSE: The aim of this study was to investigate the association of femoral (FT), tibial (TT), and knee torsion (KT) on the patella tilt (PT), the axial engagement index (AEI), and the tibial tuberosity-trochlear groove distance (TTTG). METHODS: Femoral torsion, tibial torsion, knee torsion, patella tilt, the axial engagement index, the TTTG, and trochlear dysplasia were retrospectively evaluated on 59 patients suffering from recurrent patella instability or anterior knee pain with 118 torsional lower limb magnetic resonance imaging studies. RESULTS: FT and TT did not show any significant associations with TTTG, PT, and AEI (n.s.). KT was significantly associated with a higher TTTG, higher PT, and lower AEI (all, p < 0.001). Higher grade trochlear dysplasia was associated with a higher PT and lower AEI (both, p < 0.001). The Dejour classification showed no significant association with FT, TT, KT, and TTTG (n.s.). All measurement parameters showed an excellent interrater agreement (ICC 0.89-0.97). CONCLUSIONS: Static patella tilt and patellofemoral axial engagement in knee extension are mainly influenced by knee torsion, TTTG, and trochlear dysplasia but not by femoral or tibial torsion. These findings help to understand the underlying reasons for the patella position in knee extensions in CT and MRI investigations in patients suffering from patella instability and patellofemoral pain syndrome. LEVEL OF EVIDENCE: III.


Asunto(s)
Fémur/fisiopatología , Inestabilidad de la Articulación/fisiopatología , Articulación de la Rodilla/fisiopatología , Rótula/fisiopatología , Tibia/fisiopatología , Adolescente , Adulto , Desviación Ósea/diagnóstico por imagen , Desviación Ósea/patología , Desviación Ósea/fisiopatología , Femenino , Humanos , Inestabilidad de la Articulación/diagnóstico por imagen , Inestabilidad de la Articulación/patología , Articulación de la Rodilla/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tibia/patología , Tomografía Computarizada por Rayos X , Adulto Joven
3.
Eur J Orthop Surg Traumatol ; 30(2): 267-274, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31820095

RESUMEN

INTRODUCTION: Single-item questions assessing patient satisfaction following total hip or knee arthroplasty (THA/TKA) provide immediate and comprehensible information. However, they have limited reliability as satisfaction as a concept is influenced by factors unrelated to surgery. The aim of this retrospective study was to evaluate variation in pain, function and joint awareness relative to the patients' satisfaction response following THA/TKA. METHODS: We analysed absolute and improvement scores on the Oxford Knee or Hip score (OKS or OHS) and the Forgotten Joint Score-12 (FJS-12) across satisfaction groups. Patient-reported outcome measures were assessed prior to surgery and at 12-month follow-up. Postoperative satisfaction was assessed using a 5-point Likert scale single-item question. RESULTS: We analysed data from 434 TKA patients (mean age 70.4 ± 9.2 years; 54.8% female) and 247 THA patients (mean age 67.3 ± 11.8 years; 57.5% female). Satisfied or very satisfied patients showed higher absolute scores and better improvement in function, pain and joint awareness at 12 months (both, p < 0.001). 13.4% of (very) satisfied THA patients scored equally or worse on the FJS-12 than before surgery. On the OHS, this percentage was 2.8%. In TKAs, these percentages were 7.0% on the FJS-12 and 3.2% on the OKS. CONCLUSIONS: While higher satisfaction is associated with better patient-reported outcomes and stronger postoperative improvement, a certain percentage of patients score poorly while reporting a high satisfaction. Our results highlight the difficulty in interpreting the meaning of a single satisfaction question, as this provides limited information on patients' treatment outcome and may be biased by factors unrelated to the intervention.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Dolor Postoperatorio/epidemiología , Satisfacción del Paciente/estadística & datos numéricos , Recuperación de la Función , Actividades Cotidianas , Anciano , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/psicología , Artroplastia de Reemplazo de Cadera/estadística & datos numéricos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Artroplastia de Reemplazo de Rodilla/psicología , Artroplastia de Reemplazo de Rodilla/estadística & datos numéricos , Femenino , Humanos , Masculino , Dolor Postoperatorio/etiología , Estudios Retrospectivos
4.
Psychol Med ; 48(10): 1634-1643, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29048273

RESUMEN

BACKGROUND: Prior research has typically found a negative relationship between chronic pain and memory, and we examined whether cognitive control processes (e.g. reflection and rumination) moderated this relationship in individuals with Chiari malformation Type I (CM). CM is a neurological condition in which the cerebellar tonsils descend into the medullary and upper cervical spine regions potentially resulting in severe headaches and neck pain. METHODS: CM patients who had (n = 341) and had not (n = 297) undergone decompression surgery completed the McGill Pain Questionnaire-Short Form-Revised (SF-MPQ-2), the Rey Auditory Verbal Learning Test (RAVLT), and the Rumination-Reflection Questionnaire (RRQ). Immediate recall scores were compared to those of 102 healthy controls, and delayed recall performance was compared across other variables within the CM group. RESULTS: CM patients performed more poorly on immediate recall than did controls. Within CM patients, we observed main effects for reflection and age, and a pain x reflection x surgical status (surgery v. no surgery) interaction in which non-decompressed individuals with low levels of pain and high levels of reflection showed superior delayed recall relative to non-decompressed individuals with higher pain and all decompressed individuals. CONCLUSIONS: CM patients show an immediate recall deficit relative to controls, regardless of surgical status. High levels of reflection were associated with better delayed recall performance in non-decompressed CM patients with lower pain levels. High levels of chronic pain may overwhelm increased focused attention abilities, but higher levels of reflection partially overcome the distracting effects of pain and this may represent a type of resilience.


Asunto(s)
Malformación de Arnold-Chiari/fisiopatología , Malformación de Arnold-Chiari/cirugía , Atención/fisiología , Dolor Crónico/fisiopatología , Disfunción Cognitiva/fisiopatología , Memoria a Corto Plazo/fisiología , Recuerdo Mental/fisiología , Evaluación de Resultado en la Atención de Salud , Sistema de Registros , Rumiación Cognitiva/fisiología , Adulto , Malformación de Arnold-Chiari/complicaciones , Dolor Crónico/etiología , Disfunción Cognitiva/etiología , Descompresión Quirúrgica , Femenino , Humanos , Masculino
5.
BMC Musculoskelet Disord ; 19(1): 5, 2018 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-29310652

RESUMEN

BACKGROUND: Joint awareness was recently introduced as a new concept for outcome assessment after total knee arthroplasty (TKA). Findings from qualitative and psychometric studies suggest that joint awareness is a distinct concept especially relevant to patients with good surgical outcome and patients at late follow-up time points. The aim of this study was to improve the understanding of the concept of joint awareness by identifying situations in which patients are aware of their artificial knee joint and to investigate what bodily sensations and psychological factors raise a patient's awareness of her/his knee. In addition, we evaluated the relative importance of patient-reported outcome parameters that are commonly assessed in orthopaedics. METHODS: Qualitative interviews were conducted with patients being at least 12 months after TKA. The interviews focused on when, where and for what reasons patients were aware of their artificial knee joint. To evaluate the relative importance of 'joint awareness' after TKA among nine commonly assessed outcome parameters (e.g. pain or stiffness), we collected importance ratings ('0' indicating no importance at all and '10' indicating high importance). RESULTS: We conducted interviews with 40 TKA patients (mean age 69.0 years; 65.0% female). Joint awareness was found to be frequently triggered by kneeling on the floor (30%), climbing stairs (25%), and starting up after resting (25%). Patients reported joint awareness to be related to activities of daily living (68%), specific movements (60%), or meteoropathy (18%). Sensations causing joint awareness included pain (45%) or stiffness (15%). Psychological factors raising a patient's awareness of his/her knee comprised for example feelings of insecurity (15%), and fears related to revision surgeries, inflammations or recurring pain (8%). Patients' importance ratings of outcome parameters were generally high and did not allow differentiating clearly among them. CONCLUSIONS: We have identified a wide range of situations, activities, movements and psychological factors contributing to patients' awareness of their artificial knee joints. This improves the understanding of the concept of joint awareness and of a patient's perception of his/her artificial knee joint. The diversity of sensations and factors raising patient's awareness of their joint encourages taking a broader perspective on outcome after TKA.


Asunto(s)
Actividades Cotidianas/psicología , Artroplastia de Reemplazo de Rodilla/psicología , Concienciación , Prótesis de la Rodilla , Dimensión del Dolor/psicología , Anciano , Artroplastia de Reemplazo de Rodilla/tendencias , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor/tendencias
6.
Knee Surg Sports Traumatol Arthrosc ; 26(11): 3257-3264, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29417168

RESUMEN

PURPOSE: This study investigated the impact of body mass index (BMI) on improvement in patient outcomes (pain, function, joint awareness, general health and satisfaction) following total knee arthroplasty (TKA). METHODS: Data were obtained for primary TKAs performed at a single centre over a 12-month period. Data were collected pre-operatively and 12-month postoperatively with the Oxford Knee Score (OKS) measuring pain and function, the EQ-5D-3L measuring general health status, the Forgotten Joint Score-12 (FJS-12) measuring joint awareness and a single question on treatment satisfaction. Change in scores following surgery was compared across the BMI categories identified by the World Health Organization (< 25.0, 25.0-29.9, 30.0-34.9, 35.0-39.9 and ≥ 40.0). Differences in postoperative improvement between the BMI groups were analysed with an overall Kruskal-Wallis test, with post hoc pairwise comparisons between BMI groups with Mann-Whitney tests. RESULTS: Of 402 patients [mean age 70.7 (SD 9.2); 55.2% women] 15.7% were normal weight (BMI < 25.0), 33.1% were overweight (BMI 25.0-29.9), 28.2% had class I obesity (BMI 30.0-34.9), 16.2% had class II obesity (BMI 35.0-39.9), and 7.0% had class III obesity (BMI ≥ 40.0). Postoperative change in OKS (n.s.) and EQ-5D-3L (n.s.) was not associated with BMI. Higher BMI group was associated with less improvement in FJS-12 scores (p = 0.010), reflecting a greater awareness of the operated joint during activity in the most obese patients. Treatment satisfaction was associated with BMI category (p = 0.029), with obese patients reporting less satisfaction. CONCLUSIONS: In TKA patients, outcome parameters are influenced differently by BMI. Our study showed a negative impact of BMI on postoperative improvement in joint awareness and satisfaction scores, but there was no influence on pain, function or general health scores. This information may be useful in terms of setting expectations expectation in obese patients planning to undergo TKA. LEVEL OF EVIDENCE: Level 1.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Índice de Masa Corporal , Obesidad/complicaciones , Osteoartritis de la Rodilla/cirugía , Medición de Resultados Informados por el Paciente , Anciano , Artroplastia de Reemplazo de Rodilla/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/fisiopatología , Osteoartritis de la Rodilla/complicaciones , Osteoartritis de la Rodilla/fisiopatología , Sobrepeso/complicaciones , Sobrepeso/fisiopatología , Satisfacción del Paciente , Propiocepción , Recuperación de la Función , Resultado del Tratamiento
7.
Bone Joint J ; 99-B(2): 218-224, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28148664

RESUMEN

AIMS: To validate the English language Forgotten Joint Score-12 (FJS-12) as a tool to evaluate the outcome of hip and knee arthroplasty in a United Kingdom population. PATIENTS AND METHODS: All patients undergoing surgery between January and August 2014 were eligible for inclusion. Prospective data were collected from 205 patients undergoing total hip arthroplasty (THA) and 231 patients undergoing total knee arthroplasty (TKA). Outcomes were assessed with the FJS-12 and the Oxford Hip and Knee Scores (OHS, OKS) pre-operatively, then at six and 12 months post-operatively. Internal consistency, convergent validity, effect size, relative validity and ceiling effects were determined. RESULTS: Data for the TKA and THA patients showed high internal consistency for the FJS-12 (Cronbach α = 0.97 in TKAs, 0.98 in THAs). Convergent validity with the Oxford Scores was high (r = 0.85 in TKAs, r = 0.79 for THAs). From six to 12 months, the change was higher for the FJS-12 than for the OHS in THA patients (effect size d = 0.21 versus -0.03). Ceiling effects at one-year follow-up were low for the FJS-12 with just 3.9% (TKA) and 8.8% (THA) of patients achieving the best possible score. CONCLUSION: The FJS-12 has strong measurement properties in terms of validity, internal consistency and sensitivity to change in TKA and THA patients. Low ceiling effects and good relative validity allow the monitoring of longer term outcomes, particularly in well-performing groups after total joint arthroplasty. Cite this article: Bone Joint J 2017;99-B:218-24.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Indicadores de Salud , Osteoartritis/cirugía , Anciano , Artroplastia de Reemplazo de Cadera/psicología , Artroplastia de Reemplazo de Rodilla/psicología , Concienciación , Femenino , Humanos , Masculino , Osteoartritis/psicología , Evaluación de Resultado en la Atención de Salud , Estudios Prospectivos , Psicometría , Recuperación de la Función , Reino Unido
8.
Patient Educ Couns ; 99(12): 2012-2017, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27506581

RESUMEN

OBJECTIVE: To investigate cancer patients' understanding of graphical presentations of longitudinal EORTC QLQ-C30 scores. METHODS: We conducted semi-structured interviews with brain tumour patients participating in routine patient-reported outcome (PRO) monitoring. We assessed understanding of longitudinal quality of life (QOL) profiles, presented as bar charts objectively and with self-ratings. In addition, patients' opinions on congruency of the QOL scores with their self-perceived health status were evaluated. RESULTS: We recruited 40 brain tumour patients (57.5% female; mean age 52.7, SD 13.7). In total, 90% of patients rated the graphs as easy to understand. Accordingly, almost all questions on assessing understanding objectively were answered correctly by at least 80% of the patients. More than 95% indicated that the displayed QOL scores matched their personal perception of symptom burden and functional health in the observed period. CONCLUSION: Patients are able to understand their QOL results when presented graphically and are able to interpret important changes. Displayed QOL scores obtained with the EORTC QLQ-C30 are consistent with the patients' personal perception of physical and emotional functioning, pain and fatigue. PRACTICE IMPLICATIONS: Knowledge about patients' understanding of graphically displayed QOL results contributes to creation of optimal evidence-based feedback on the patients' present QOL and its trajectory.


Asunto(s)
Neoplasias Encefálicas/psicología , Comprensión , Gráficos por Computador , Alfabetización en Salud , Calidad de Vida , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Fatiga , Femenino , Humanos , Entrevistas como Asunto , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Medición de Resultados Informados por el Paciente , Investigación Cualitativa , Encuestas y Cuestionarios
9.
Magn Reson Imaging ; 18(6): 697-706, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10930779

RESUMEN

In this paper, a method of three-dimensional (3D) vessel localization is presented to allow the identification of a vessel of interest, the selection of a vessel segment, and the determination of a slice orientation to improve the accuracy of phase-contrast magnetic resonance (PCMR) angiography. A marching-cube surface-rendering algorithm was used to reconstruct the 3D vasculature. Surface-rendering was obtained using an iso-surface value determined from a maximum intensity projection (MIP) image. This 3D vasculature was used to find a vessel of interest, select a vessel segment, and to determine the slice orientation perpendicular to the vessel axis. Volumetric flow rate (VFR) was obtained in a phantom model and in vivo using 3D localization with double oblique cine PCMR scanning. PCMR flow measurements in the phantom showed 5. 2% maximum error and a standard deviation of 9 mL/min during steady flow, 7.9% maximum error and a standard deviation of 13 mL/min during pulsatile flow compared with measurements using an ultrasonic transit-time flowmeter. PCMR VFR measurement error increased with misalignment at 10, 20, and 30 degrees oblique to the perpendicular slice in vitro and in vivo. The 3D localization technique allowed precise localization of the vessel of interest and optimal placement of the slice orientation for minimum error in flow measurements.


Asunto(s)
Encéfalo/anatomía & histología , Arterias Carótidas/anatomía & histología , Angiografía por Resonancia Magnética/métodos , Velocidad del Flujo Sanguíneo , Encéfalo/irrigación sanguínea , Arterias Carótidas/fisiología , Arterias Cerebrales/anatomía & histología , Arterias Cerebrales/fisiología , Humanos , Imagen por Resonancia Cinemagnética/métodos , Flujo Sanguíneo Regional
10.
Joint Bone Spine ; 68(1): 74-5, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11235786

RESUMEN

Bone lesions are fairly uncommon in sarcoidosis (5 to 10% of cases). We report the case of a 40-year-old man in whom sarcoidosis of the lungs and bones was revealed by excruciating buttock and sacral pain. Computed tomography showed multiple punched-out defects in the left iliac bone. No similar cases have been reported in the literature.


Asunto(s)
Enfermedades Óseas/diagnóstico por imagen , Ilion/diagnóstico por imagen , Sarcoidosis/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Humanos , Masculino , Dolor/etiología
11.
Surg Neurol ; 54(2): 145-52; discussion 152-3, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11077096

RESUMEN

BACKGROUND: Recent publications have pointed out the importance of evaluating patients with in-tandem stenosis and in particular the association of moderate stenosis of the extracranial internal carotid artery (ICA) with moderate or severe stenosis of the intracranial internal carotid artery. Such evaluations are needed in symptomatic patients before planning carotid endarterectomies because observations have shown that in some cases the removal of an extracranial lesion does not necessarily improve these symptoms. This paper examines the hemodynamic effects of in-tandem stenosis in the internal carotid artery. METHODS: Equations describing flow in arteries are modified to accommodate two regions of stenosis in tandem. An equivalent value of stenosis is derived such that two stenoses in tandem behave as a single stenosis with similar hemodynamic properties. The solution to this problem is solved mathematically and this was used to analyze the observations made in five studies published on in-tandem stenosis of the internal carotid artery. RESULTS: Equivalent stenoses for various values of extracranial and intracranial stenoses are presented. It was found that two stenotic lesions in tandem are not equivalent to a simple summation of both values. A graphical solution is presented to show the hemodynamic effects of both stenoses. CONCLUSIONS: The most critical determinant of hemodynamic compromise when two lesions are in tandem is the larger one. Hence removal of a more proximal lesion may have little effect on a larger distal lesion if the symptoms are due to hypoperfusion. It is important that one distinguish between hypoperfusion and thromboembolic causes of the symptoms. No conclusions about the risk of thromboembolic events after a carotid endarterectomy in the setting of a distal stenosis can be made from this study.


Asunto(s)
Encéfalo/irrigación sanguínea , Arteria Carótida Interna/cirugía , Estenosis Carotídea/cirugía , Endarterectomía Carotidea , Hemodinámica/fisiología , Anciano , Anciano de 80 o más Años , Velocidad del Flujo Sanguíneo/fisiología , Arteria Carótida Interna/fisiopatología , Estenosis Carotídea/fisiopatología , Diagnóstico por Imagen , Femenino , Humanos , Modelos Teóricos
12.
Neurosurg Focus ; 11(1): E6, 2001 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-16724816

RESUMEN

OBJECT: A pilot study was performed to assess noninvasively the change in intracranial compliance (ICC) and intracranial pressure (ICP) in patients with Chiari I malformation who undergo foramen magnum decompression. The working hypothesis was that the main effect of the decompressive surgery is a change in ICP. Noninvasive cine phasecontrast magnetic resonance (MR) imaging is a motion-sensitive dynamic MR imaging technique that allows for visualization and quantitation of tissue motion and flow. The authors' group has used dynamic phase-contrast MR imaging to visualize and quantify pulsatile blood and cerebrospinal fluid (CSF) flow in the craniospinal system. METHODS: A system approach has been used to characterize the hemodynamic-hydrodynamic coupling in the craniospinal system and to derive measures for ICC and ICP. Magnetic resonance imaging-based ICC and ICP values are derived from the ratio of the volume and pressure changes that occur naturally during each cardiac cycle. The authors conducted a prospective study of four patients, three of whom were studied before and after decompressive surgery; significant change in MR imaging-derived ICC and ICP values was documented in only one of the three surgically treated patients. A significant change in the dynamics of the intracranial volume change (ICVC) during the cardiac cycle, however, was observed in all three patients. In healthy individuals the ICVC waveform usually consists of the following sequence: monotonic increase in intracranial volume (ICV) during the systolic phase due to increased blood inflow, monotonic decrease in ICV caused by the onset of CSF outflow into the spinal canal, and increase in the venous outflow. A nonmonotonic decline in the ICVC waveform has been observed in all patients with headaches, and a relatively normal waveform was found in those without headaches or whose headaches were resolved or alleviated by the surgery. A "partial-valve" mechanism is proposed as an explanation for the abnormal ICVC dynamics. The monotonic decline in ICVC is interrupted by a "premature" reduction in the CSF outflow. This may be caused by a displacement of the hindbrain into the cervical spinal canal during the systolic phase. This obstructs the CSF flow at the later part of the systolic phase such that the ICV does not continue its gradual decline. Postsurgery, the ICVC waveforms presented a more normal-appearing ICVC dynamics profile. CONCLUSIONS: Magnetic resonance imaging measurement of transcranial CSF and blood flow may lead to a better understanding of the pathophysiology of Chiari malformations and may prove to be an important diagnostic tool for guiding for the treatment of patients with Chiari I malformation.


Asunto(s)
Malformación de Arnold-Chiari/sangre , Malformación de Arnold-Chiari/líquido cefalorraquídeo , Velocidad del Flujo Sanguíneo/fisiología , Presión del Líquido Cefalorraquídeo/fisiología , Imagen por Resonancia Magnética , Adulto , Malformación de Arnold-Chiari/patología , Malformación de Arnold-Chiari/cirugía , Cerebelo/patología , Cerebelo/cirugía , Circulación Cerebrovascular/fisiología , Adaptabilidad , Descompresión Quirúrgica/métodos , Femenino , Foramen Magno/patología , Hemodinámica/fisiología , Humanos , Hidrocefalia/sangre , Hidrocefalia/líquido cefalorraquídeo , Hidrocefalia/patología , Hidrocefalia/cirugía , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Modelos Biológicos , Proyectos Piloto , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Factores de Tiempo
13.
ASAIO J ; 41(3): M430-4, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8573840

RESUMEN

The removal of endotoxins by extracorporeal adsorption processes seems the most promising therapeutic approach to Gram-negative sepsis and endotoxin shock. However, thus far adsorbents have failed to bind endotoxins efficiently or have shown adverse biocompatibility characteristics. To overcome these disadvantages, small particles of regenerated cellulose in the range of 1-8 microns in diameter were produced. Before use, the microspheres were cationically modified by substitution with polyethyleneimine (PEI) or diethylaminoethyl (DEAE) groups. A third kind of adsorbent was manufactured by (physically) coating the cellulose matrix with PEI. All three types of adsorbents exhibited a high adsorption capacity for endotoxins in human plasma, whereas activated charcoal and various anion exchange resins removed only small amounts of endotoxins under the same conditions. In addition, because the outer surface area is very large, adsorption takes place rapidly and diffusion becomes almost irrelevant. The adsorption process is primarily based on electrostatic interactions, which could be demonstrated by a significantly higher adsorption rate and binding capacity for lipid A-diphosphoryl, compared with lipid A-monophosphoryl. Use of these adsorbents in a newly developed plasma sorption system could be of great clinical interest because of the low production costs, the high adsorption efficiency, and the excellent biocompatibility data.


Asunto(s)
Endotoxinas/sangre , Endotoxinas/aislamiento & purificación , Hemoperfusión/métodos , Animales , Materiales Biocompatibles , Proteínas Sanguíneas/aislamiento & purificación , Cationes , Celulosa/química , Estudios de Evaluación como Asunto , Infecciones por Bacterias Gramnegativas/terapia , Humanos , Técnicas In Vitro , Lípido A/sangre , Lípido A/aislamiento & purificación , Lipopolisacáridos/sangre , Lipopolisacáridos/aislamiento & purificación , Ensayo de Materiales , Sepsis/terapia , Choque Séptico/terapia , Porcinos
14.
Int J Artif Organs ; 17(11): 595-602, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7744520

RESUMEN

Plasma sorption processes have so far been performed with filters and appropriate adsorption columns. In this paper, we introduce a newly developed plasma sorption system, which is based on the high adsorption capacity of microspheres in a recirculation system. The technology has been applied successfully in vitro to eliminate endotoxins, low density lipoproteins (LDL) and barbiturates from human plasma.


Asunto(s)
Barbitúricos/sangre , Endotoxinas/sangre , Lipoproteínas LDL/sangre , Microesferas , Desintoxicación por Sorción/normas , Animales , Barbitúricos/química , Barbitúricos/aislamiento & purificación , Bovinos , Cromatografía Líquida de Alta Presión , Endotoxinas/química , Endotoxinas/aislamiento & purificación , Humanos , Lipoproteínas LDL/química , Lipoproteínas LDL/aislamiento & purificación , Presión , Estándares de Referencia , Desintoxicación por Sorción/tendencias , Porcinos
15.
Gastroenterol Clin Biol ; 22(6-7): 634-8, 1998.
Artículo en Francés | MEDLINE | ID: mdl-9762335

RESUMEN

Aseptic osteonecrosis is a rare extraintestinal manifestation in patients with inflammatory bowel disease; its true prevalence is not precisely known. Steroid treatment undoubtedly participates in the pathophysiology of avascular osteonecrosis, however, other factors like hypercoagulability may be involved. Two cases of bilateral osteonecrosis of the knees--the first occurring during the course of ulcerative colitis, the second in a patient presenting with Crohn's disease--are described. Specific location of the lesions and regression of symptoms, as well as the importance of magnetic resonance imaging for early recognition of osteonecrosis, are noteworthy.


Asunto(s)
Colitis Ulcerosa/etiología , Enfermedad de Crohn/complicaciones , Epífisis/irrigación sanguínea , Isquemia/etiología , Adulto , Femenino , Humanos , Masculino
16.
Pharmazie ; 41(4): 250-3, 1986 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-3725867

RESUMEN

A new procedure of microencapsulation was studied with regard to substance release and quantification of diffusion processes on the capsule membrane. The permeability behaviour on the capsule membrane was especially studied in metabolites, which are essential for immobilized biological objects (i.g. preimplantative mammal embryos). Peptide and proteohormones, cyanmethemoglobin and proteins were enclosed in simple and multiple Symplex Capsules. All substances examined are able to pass the Symplex membrane. The speed of release is influenced by the size of the capsule, the ion force, temperature, concentration of immobilized substances as well as their linear and globular structur. Compared with simple capsules the release of substances from multiple capsules was delayed. Corresponding to the results found under the experimental design described the Symplex membrane can be considered as coating for the compartmentation of cells, that allows the passage of essential substances for the immobilized objects. The method of microencapsulation used and described has various ways of application.


Asunto(s)
Cápsulas , Fenómenos Químicos , Química Farmacéutica , Química Física , Estabilidad de Medicamentos , Radioisótopos de Yodo , Factores de Tiempo
19.
Artículo en Alemán | MEDLINE | ID: mdl-3407255

RESUMEN

A biomaterial on cellulose basis capable of swelling was developed for a progressive occlusion of vessels. Pathologic courses of the human arteriosclerosis can be imitated in animal experiment by means of this material.


Asunto(s)
Arteriosclerosis/fisiopatología , Materiales Biocompatibles , Tromboembolia/fisiopatología , Animales , Celulosa , Modelos Animales de Enfermedad , Humanos
20.
Artículo en Alemán | MEDLINE | ID: mdl-3407256

RESUMEN

Occlusions of different visceral arteries were imitated by progressive swelling substance constriction in 30 mongrel dogs. The variants of the developed collateral circulation could be proved by the postoperative angiographies. There is given reference to the importance of the connections of the visceral vascular system among one another and for the abdominal surgery of the human. Evidence is given that occlusions of the celiac artery and of the superior mesenteric artery are compensable only with the formation of large collateral vascular systems. But on certain circulation conditions the inferior mesenteric artery has a great significance too.


Asunto(s)
Arteriopatías Oclusivas/fisiopatología , Arteria Celíaca/fisiología , Arterias Mesentéricas/fisiología , Animales , Modelos Animales de Enfermedad , Perros , Humanos , Arterias Mesentéricas/diagnóstico por imagen , Métodos , Radiografía
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