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1.
J Orthop Case Rep ; 8(5): 67-71, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30740380

RESUMEN

INTRODUCTION: Treatment and risk factors for Parvimonas micra spinal infections are scarcely researched. This study reports a case and presents a systematic review of the literature to provide evidence-based ground for diagnosis and treatment of P. micra spinal infections. CASE REPORT: This is a case of a 78-year-old male with severe back and leg pain. Advanced imaging demonstrated the destruction of L2-L3 with an extensive fluid collection in the remaining intervertebral space, paravertebral myositis, and multiple abscesses. A decompression of L2 and L3 and a posterior spondylodesis from T12 to L5 was performed. Intraoperative cultures showed P. micra. The postoperative treatment consisted of intravenous penicillin for 2 weeks and subsequent oral clindamycin for 4 weeks. At 1-year follow-up, the patient was in good health and reported only occasional back pain. CONCLUSIONS: A total of 15 additional cases of P. micraspinal infections were identified. The antibiotic treatment showed a great variety in the treated patients. Nevertheless, the outcome of these patients was good concerning relapse of the infection and pain. Spinal infections caused by P. micra are rare, but can be successfully treated according to the guidelines for spinal infection.

2.
Best Pract Res Clin Anaesthesiol ; 30(4): 499-510, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27931653

RESUMEN

Differences in physiology and pathophysiology make the treatment of developing, critically ill children particularly challenging as compared to that of adults. Significant differences in the cardiovascular system of neonates and children in size, weight, body proportions, and metabolism should be considered. Hemodynamic monitoring is crucial for early warning of pending deterioration and to guide therapy. Current monitoring is limited to the macrocirculation, but an adequately functioning macrocirculation does not guarantee a well-functioning microcirculation. Research in children revealed loss of hemodynamic coherence, i.e., microcirculatory alterations despite normal systemic hemodynamics. Implementing the framework of hemodynamic coherence in microcirculatory monitoring in children can aid physicians in titrating therapy on both macrocirculatory and microcirculatory effects to assure optimal oxygen delivery. Monitoring the microcirculation at the bedside requires further technical development. Although more research is necessary to validate the concept of hemodynamic coherence in children, the possibilities of applying this concept in children seem promising.


Asunto(s)
Enfermedad Crítica , Hemodinámica , Niño , Humanos , Microcirculación , Microscopía por Video
3.
Crit Care ; 20(1): 352, 2016 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-27794361

RESUMEN

In neonates, cardiovascular system development does not stop after the transition from intra-uterine to extra-uterine life and is not limited to the macrocirculation. The microcirculation (MC), which is essential for oxygen, nutrient, and drug delivery to tissues and cells, also develops. Developmental changes in the microcirculatory structure continue to occur during the initial weeks of life in healthy neonates. The physiologic hallmarks of neonates and developing children make them particularly vulnerable during critical illness; however, the cardiovascular monitoring possibilities are limited compared with critically ill adult patients. Therefore, the development of non-invasive methods for monitoring the MC is necessary in pediatric critical care for early identification of impending deterioration and to enable the initiation and titration of therapy to ensure cell survival. To date, the MC may be non-invasively monitored at the bedside using hand-held videomicroscopy, which provides useful information regarding the microcirculation. There is an increasing number of studies on the MC in neonates and pediatric patients; however, additional steps are necessary to transition MC monitoring from bench to bedside. The recently introduced concept of hemodynamic coherence describes the relationship between changes in the MC and macrocirculation. The loss of hemodynamic coherence may result in a depressed MC despite an improvement in the macrocirculation, which represents a condition associated with adverse outcomes. In the pediatric intensive care unit, the concept of hemodynamic coherence may function as a framework to develop microcirculatory measurements towards implementation in daily clinical practice.


Asunto(s)
Enfermedad Crítica/terapia , Monitorización Hemodinámica/tendencias , Microcirculación/fisiología , Pediatría/métodos , Monitorización Hemodinámica/métodos , Hemodinámica/fisiología , Humanos , Lactante , Recién Nacido , Unidades de Cuidado Intensivo Neonatal/organización & administración , Pediatría/normas
4.
Acta Orthop Belg ; 82(2): 149-160, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27682274

RESUMEN

Recently, guidelines regarding diagnosis and treatment of periprosthetic joint infection (PJI) have been published, but it is unknown how well these are -followed in the Netherlands and Belgium. Therefore, a survey study was performed in the Netherlands and Belgium. 81 orthopedic departments responded (54% in the Netherlands, 52% in Belgium). The majority used protocols for antibiotic and surgical treatment. To discriminate between early and late infection, differences in periods used were seen between respondents, and between countries. Empirical antibiotic treatment varied greatly. Debridement, antibiotics, irrigation and retention of the prosthesis (DAIR) is the -almost unanimous treatment of choice for early PJI. Guidelines are available, but seem not (yet) to be -followed accurately, and do not have answers to all possible treatment options. Perhaps, national guidelines might produce more standardized care, and -consequentially, easier comparison for research, more transparency for patients, and less health care costs.


Asunto(s)
Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Adhesión a Directriz , Guías de Práctica Clínica como Asunto , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones Relacionadas con Prótesis/terapia , Antibacterianos/uso terapéutico , Artroplastia de Reemplazo de Cadera/estadística & datos numéricos , Artroplastia de Reemplazo de Rodilla/estadística & datos numéricos , Bélgica , Desbridamiento , Humanos , Países Bajos , Irrigación Terapéutica
5.
Br J Pharmacol ; 165(2): 532-9, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21745192

RESUMEN

BACKGROUND AND PURPOSE: Bisphosphonate-related osteonecrosis of the jaw (BRONJ) has been identified as a severe complication of patients previously treated with i.v. bisphosphonates. It has been noted that necrotic bone from BRONJ sites display signs of bacterial infection suggesting that an immune defect may play a role in the pathophysiology of BRONJ. Here, we have examined the effect of two potent bisphosphonates, zoledronate and pamidronate, on neutrophil function, differentiation and survival. EXPERIMENTAL APPROACH: The effect of bisphosphonates on chemotaxis, NADPH oxidase activity and neutrophil survival were assessed in vitro using bone marrow-derived primary neutrophils or in vitro differentiated haematopoetic progenitors from mice. The same parameters and the number of circulating neutrophils were quantified in neutrophils isolated from mice treated in vivo with zoledronate. In vivo recruitment of neutrophils was assessed by sodium periodate-induced peritonitis. KEY RESULTS: Zoledronate and pamidronate inhibited in vitro neutrophil chemotaxis and NADPH oxidase activity in a dose-dependent manner. In vivo recruitment of neutrophils was also suppressed. Zoledronate did not affect in vitro differentiation of neutrophils but shortened their life span in a granulocyte-colony stimulating factor-dependent manner. fMLP-induced activation of RhoA activity was decreased by zoledronate treatment. CONCLUSIONS AND IMPLICATIONS: Our results show that bisphosphonate exposure leads to impaired neutrophil chemotaxis, neutrophil NADPH oxidase activity and reduced circulating neutrophil counts. This work suggests that bisphosphonates have the potential to depress the innate immune system for a prolonged time, possibly contributing to the pathogenesis of BRONJ.


Asunto(s)
Conservadores de la Densidad Ósea/farmacología , Difosfonatos/farmacología , Imidazoles/farmacología , Neutrófilos/efectos de los fármacos , Animales , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Quimiotaxis de Leucocito/efectos de los fármacos , Recuento de Leucocitos , Ratones , Ratones Endogámicos C57BL , NADPH Oxidasas/metabolismo , Neutrófilos/inmunología , Neutrófilos/metabolismo , Pamidronato , Ácido Zoledrónico
6.
Eur Respir J ; 32(6): 1599-606, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18768578

RESUMEN

Pneumonia, the main cause of acute lung injury, is characterised by a local pro-inflammatory response and coagulopathy. Mechanical ventilation (MV) is often required. However, MV can lead to additional injury: so-called ventilator-induced lung injury (VILI). Therefore, the current authors investigated the effect of VILI on alveolar fibrin turnover in Streptococcus pneumoniae pneumonia. Pneumonia was induced in rats, followed 48 h later by either lung-protective MV (lower tidal volumes (LV(T)) and positive end-expiratory pressure (PEEP)) or MV causing VILI (high tidal volumes (HV(T)) and zero end-expiratory pressure (ZEEP)) for 3 h. Nonventilated pneumonia rats and healthy rats served as controls. Thrombin-antithrombin complexes (TATc), as a measure for coagulation, and plasminogen activator activity, as a measure of fibrinolysis, were determined in bronchoalveolar lavage fluid (BALF) and serum. Pneumonia was characterised by local (BALF) activation of coagulation, resulting in elevated TATc levels and attenuation of fibrinolysis compared with healthy controls. LV(T)-PEEP did not influence alveolar coagulation or fibrinolysis. HV(T)-ZEEP did intensify the local procoagulant response: TATc levels rose significantly and levels of the main inhibitor of fibrinolysis, plasminogen activator inhibitor-1, increased significantly. HV(T)-ZEEP also resulted in systemic elevation of TATc compared with LV(T)-PEEP. Mechanical ventilation causing ventilator-induced lung injury increases pulmonary coagulopathy in an animal model of Streptococcus pneumoniae pneumonia and results in systemic coagulopathy.


Asunto(s)
Trastornos de la Coagulación Sanguínea/diagnóstico , Neumonía Bacteriana/terapia , Streptococcus pneumoniae/metabolismo , Lesión Pulmonar Inducida por Ventilación Mecánica/diagnóstico , Animales , Antitrombinas/química , Trastornos de la Coagulación Sanguínea/complicaciones , Líquido del Lavado Bronquioalveolar , Modelos Animales de Enfermedad , Fibrinólisis , Lipopolisacáridos/metabolismo , Masculino , Neumonía Bacteriana/complicaciones , Intercambio Gaseoso Pulmonar , Ratas , Ratas Sprague-Dawley , Trombina/química , Lesión Pulmonar Inducida por Ventilación Mecánica/etiología
8.
J Gastrointest Surg ; 10(7): 960-73, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16843866

RESUMEN

The aims of this study were to assess the technical effectiveness of radiofrequency (RF) ablation in patients with primary or secondary hepatic malignancies and to determine survival and complication rates. This was a retrospective analysis of prospectively collected data of patients treated with RF ablation and controlled for recurrence every 3 months by contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI). The outcome is compared with a comprehensive review of data published in recent literature. Forty-seven patients underwent 50 RF sessions for the ablation of 73 tumors. Local tumor progression was observed in 11 patients (23%). A tumor sized larger than 30 mm, a tumor load larger than 14 cm3, and a percutaneous approach were associated with a faster time to local tumor progression. At the end of a mean (+/- SD) follow-up period of 11.4 +/- 7.5 months, 39 patients (83%) were alive, including eight patients with recurrent disease. The overall cumulative survival rates at 12 and 24 months were 87% and 70%, respectively. In our center, RF ablation can be safely performed to achieve adequate local control and survival rates. Time to local tumor progression was significantly related to initial size of the tumor and tumor load.


Asunto(s)
Ablación por Catéter , Neoplasias Hepáticas/terapia , Recurrencia Local de Neoplasia , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/sangre , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/terapia , Neoplasias Colorrectales/patología , Femenino , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/secundario , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Países Bajos , Estudios Retrospectivos , Tasa de Supervivencia , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
9.
Pediatr Blood Cancer ; 44(1): 95-7, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15368548

RESUMEN

L-asparaginase is a key component of the antileukemic therapy in children with acute lymphoblastic leukemia (ALL). Pancreatitis has been noted to be a complication in 2-16% of patients undergoing treatment with L-asparaginase for a variety of pediatric neoplasms. Most cases of pancreatitis associated with L-asparaginase toxicity are self-limiting and respond favorably to nasogastric decompression and intravenous hyperalimentation. However, in rare instances, hemorrhagic pancreatitis or necrosis may occur. L-asparaginase-induced pancreatitis is an uncommon but potential lethal complication of the treatment of leukemia. We present a pediatric patient with leukemia and a severe, L-asparaginase-induced necrotizing pancreatitis, treated successfully with percutaneous drainage used to flush the infected necrotic parts.


Asunto(s)
Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Asparaginasa/efectos adversos , Drenaje/métodos , Pancreatitis Aguda Necrotizante/inducido químicamente , Pancreatitis Aguda Necrotizante/terapia , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Asparaginasa/uso terapéutico , Femenino , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Resultado del Tratamiento
10.
Br J Surg ; 90(8): 950-5, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12905547

RESUMEN

BACKGROUND: The aim was to determine the degree of local control of hepatocellular carcinoma (HCC) in patients with cirrhotic liver disease when treated with ultrasonographically guided interstitial laser coagulation (ILC) with temporary hepatic artery occlusion. METHODS: Sixteen patients with 24 HCC tumours were treated. Follow-up was by computed tomography or magnetic resonance imaging every 3 months. RESULTS: Nineteen of 24 tumours showed complete necrosis immediately after treatment, and there was no tumour recurrence during follow-up (mean 14 months, median 12 months). No effect on liver function was observed after 1 week and there was no death. In 13 of the 16 patients, new HCC foci developed at other sites. CONCLUSION: Percutaneous ILC combined with temporary hepatic artery occlusion during a single session is an effective local treatment for HCC nodules smaller than 5 cm. However, new HCC lesions develop in the majority of patients, which underscores the need for adjuvant therapy or repeated treatment in these patients.


Asunto(s)
Carcinoma Hepatocelular/cirugía , Embolización Terapéutica/métodos , Coagulación con Láser/métodos , Cirrosis Hepática/cirugía , Neoplasias Hepáticas/cirugía , Anciano , Carcinoma Hepatocelular/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Cirrosis Hepática/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Cuidados a Largo Plazo , Masculino , Persona de Mediana Edad , Análisis de Supervivencia , Tomografía Computarizada por Rayos X/métodos
11.
HPB (Oxford) ; 5(2): 100-4, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-18332965

RESUMEN

BACKGROUND: The aim was to assess the value of laparoscopy and laparoscopic ultrasonography (LUS) in selecting patients for resection of colorectal hepatic metastases. METHODS: Sixty patients with potentially resectable colorectal hepatic metastases after helical computer tomography (CT) and scheduled to undergo laparoscopy and LUS were studied retrospectively. Primary outcome measurement was the number of cases in which laparoscopy and LUS resulted in a change of therapeutic approach. RESULTS: Of the 60 patients, 59 patients were examined by LUS and/or laparoscopy. The small intestine was perforated due to adhesions in two patients, necessitating open exploration in one of them. In 17 patients (29%) the combined laparoscopic procedure yielded results prohibiting resection; another 6 patients were denied resection on other grounds. Of the 36 patients who underwent open exploration, 31 underwent resection. Combined laparoscopy and LUS predicted resectability correctly in 86% of the patient group. Compared with resection, the sensitivity of both CT and LUS to detect lesions was 91%. DISCUSSION: Laparoscopy and LUS can avoid open exploration without resection in a substantial number of patients considered eligible for resection of colorectal hepatic metastases based on CT. LUS does not seem to detect more metastases than CT.

12.
J Bone Miner Res ; 16(2): 417-26, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11204442

RESUMEN

An extensive series of dual-energy X-ray absorptiometry (DXA) scans and dual polyenergetic X-ray simulation studies of 150 different phantom arrays were carried out to evaluate quantitatively the extent of systematic inaccuracies inherent in DXA in vivo bone mineral density (BMD). These measurements are particularly relevant to lumbar vertebral and proximal femoral sites. The phantoms were specially fabricated near perfect absorptiometric representations of bone material, red marrow (RM) and yellow marrow (YM), and extraosseous mixtures of fat (F) and lean muscle that spanned the full range of soft tissue anthropometrics encountered clinically. In each case, the DXA-measured BMD values obtained using Hologic, Lunar, and Norland densitometers were found to be virtually the same and to be in excellent agreement with the corresponding quantitative simulation study BMD results. Comparisons of the known phantom BMD values and DXA-measured BMD in each case allowed the BMD inaccuracies to be evaluated. These present findings show that these ubiquitous inaccuracies in DXA BMD methodology are of in vivo soft tissue anthropometric genesis. It is found that patient-specific DXA-measured in vivo BMD inaccuracies as high as 20% or more can be readily anticipated clinically, particularly in cases of osteopenic, osteoporotic, and elderly patients. As these inaccuracies exceed considerably DXA precision errors, they may compromise patient-specific evaluations of fracture risk and, in prospective studies, mask or exaggerate clinically significant true changes in BMD. It is concluded that the magnitudes and variability of inherent inaccuracies in DXA-measured in vivo BMD underscore the need for prudence and circumspection in interpretations and assessments of DXA-based clinical studies.


Asunto(s)
Densidad Ósea , Fantasmas de Imagen , Absorciometría de Fotón , Estudios de Evaluación como Asunto , Humanos
13.
Semin Vasc Med ; 1(2): 195-204, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15199503

RESUMEN

Advancements in computed tomography (CT) have led to the development of noninvasive helical CT of the pulmonary arteries as a diagnostic tool in patients with suspected pulmonary embolism (PE). The first-generation, single-slice CT scanners were capable of acquiring one 3-mm-thick imaging section per second. As a further technical evolution of helical CT, multislice CT scanners now allow simultaneous acquisition of eight slices per second. This increased imaging speed can be used to advantage by scanning the entire thorax with 1-mm-thin imaging sections during a single breath-hold. Because of the increased spatial resolution and increased robustness to motion artifacts of multislice CT, the pulmonary arteries can now be accurately depicted up to the fifth order branches. In comparison with single-slice CT, this holds the promise of better detection of small subsegmental PE and thus, increased accuracy to detect and rule out PE. A few recent management studies suggest that single-slice CT can be used as an accurate cornerstone in the diagnostic work-up of suspected PE-a concept that will be further enhanced with multislice helical CT.


Asunto(s)
Arteria Pulmonar/diagnóstico por imagen , Embolia Pulmonar/diagnóstico por imagen , Tomografía Computarizada Espiral , Algoritmos , Anticoagulantes/administración & dosificación , Análisis Costo-Beneficio , Humanos , Embolia Pulmonar/economía , Sensibilidad y Especificidad , Tomógrafos Computarizados por Rayos X , Tomografía Computarizada Espiral/economía , Tomografía Computarizada Espiral/instrumentación , Tomografía Computarizada Espiral/métodos
14.
Ned Tijdschr Geneeskd ; 144(32): 1542-8, 2000 Aug 05.
Artículo en Holandés | MEDLINE | ID: mdl-10949638

RESUMEN

OBJECTIVE: To evaluate, in patients with hepatocellular carcinoma or colorectal carcinoma disseminated to the liver, treatment with interstitial laser coagulation (ILC) during temporary occlusion of vascular inflow in the liver: feasibility, complications and initial tumour response. DESIGN: Prospective, descriptive. METHODS: Patients were included if their tumours were surgically irresectable and smaller than 4 cm in diameter and did not exceed a number of 3. ILC was performed under general anaesthesia, basically via a percutaneous approach. Vascular inflow was occluded during laser treatment. Twenty-four hours after ILC a triphasic spiral CT was performed to assess the result of the treatment. RESULTS: In 10 patients 14 hepatic tumours were lasered in 12 treatment sessions (10 percutaneous and 2 at laparotomy). After 5 treatment sessions, complications were observed of which pain at the insertion site of the catheters was the most frequent. For 6 out of the 10 patients with percutaneous procedures, discharge was within 24 hours after ILC. Nine out of the 14 tumours (65%) were completely coagulated. CONCLUSION: ILC with vascular inflow occlusion is a safe and feasible technique that can be performed during a short hospital stay. Initial tumour response is 65% and these results justify determination of duration of response in a larger group of patients.


Asunto(s)
Carcinoma Hepatocelular/cirugía , Coagulación con Láser/métodos , Neoplasias Hepáticas/cirugía , Hígado/irrigación sanguínea , Anciano , Carcinoma Hepatocelular/secundario , Neoplasias Colorrectales/patología , Estudios de Factibilidad , Femenino , Humanos , Tiempo de Internación , Hígado/cirugía , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
15.
Maturitas ; 31(2): 151-9, 1999 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-10227009

RESUMEN

OBJECTIVE: Assessment of loss of bone density (BD) 1 year after a 2-year period of hormone replacement therapy (HRT) with two doses of Tibolone as compared to placebo in early post-menopausal women. METHODS: Sixty-four out of 84 women (1-3 years following spontaneous menopause) who completed a 2-year randomised, placebo controlled study to evaluate effects of Tibolone participated in this follow-up study. Quantitative computed tomography was used to exclusively measure trabecular BD, microdensitometry of the mid-phalangeal shaft was used for estimation of cortical BD and biochemical markers of bone metabolism were assessed, 1 year after discontinuation of Tibolone. The study group received either placebo (n = 16), 1.25 mg/day Tibolone (n = 25) or 2.5 mg/day Tibolone (n = 23). RESULTS: Observations revealed a significantly greater decrease in trabecular BD during the post-trial year in both treatment groups compared to the placebo group (for 1.25 mg/day Tibolone, -6.0%, 95% CI -8.4 to -3.5; for 2.5 mg/day Tibolone, -10.0%, 95% CI: -12.9 to -6.9). In contrast, there was no significant difference in loss of phalangeal BD in both treatment groups compared to placebo. Biochemical markers (serum alkaline phosphatase, urinary excretion of hydroxyproline and calcium) do not suggest an increased bone turnover comparing Tibolone groups to placebo, 1 year after cessation of Tibolone. CONCLUSION: The present study suggests an increased loss of trabecular but not cortical BD as compared to the placebo group in the first year after cessation of HRT with Tibolone in early post-menopausal women.


Asunto(s)
Anabolizantes/farmacología , Densidad Ósea/efectos de los fármacos , Resorción Ósea/metabolismo , Terapia de Reemplazo de Estrógeno , Norpregnenos/farmacología , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad
16.
Calcif Tissue Int ; 62(3): 214-8, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9501954

RESUMEN

In this study a new reference value, "corrected vertebral dimension," is presented for vertebral height measurements. Of 68 females (age 18-88 years; mean 44.2 years) and 40 males (age 16-81 years; mean 55 years) the projected vertebral dimensions (T4-L5) were measured on lateral radiographs. In addition to this, the vertebra-to-film distances (VFD) were measured and a fixed focus-to-film distance (FFD) was used during the study. Corrected dimensions of the thoracic and lumbar vertebrae (T4-L5) were calculated using the FFD and VFD. These corrected dimensions were then used to recalculate projected vertebral dimensions at different focus-to-film distances. The applied geometric corrections were verified in a phantom study representing an in vitro situation. The results indicate that studies using different X-ray techniques for making lateral radiographs of the spine can become comparable when using corrected vertebral dimensions.


Asunto(s)
Vértebras Lumbares/anatomía & histología , Vértebras Torácicas/anatomía & histología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Constitución Corporal , Femenino , Humanos , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Osteoporosis/diagnóstico , Fantasmas de Imagen , Radiografía , Valores de Referencia , Reproducibilidad de los Resultados , Vértebras Torácicas/diagnóstico por imagen , Rayos X
17.
Invest Radiol ; 32(2): 83-9, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9039579

RESUMEN

METHODS: The relation between geometry and the distribution of trabecular and cortical bone mass and density in the human femoral neck was evaluated with quantitative computed tomography (QCT). Quantitative computed tomography data were obtained from 2-mm thick computed tomography slices of 20 human femur necks in vitro. A standardized scan position in each femur was used with the smallest cross-section as reference point. RESULTS: When trabecular bone mass (TrBM) and cortical bone mass were presented as percentage of total bone mass (ToBM), it was found that, starting at the cranial (head) side, ToBM consists of 78% TrBM. About 21% of ToBM can be found as TrBM at the caudal (trochanter) side. At the smallest cross-sectional volume TrBM is 33% of ToBM. For every 2-mm slice, an average decrease of 5% TrBM can be seen. CONCLUSIONS: These data show that geometry and bone mass distribution are related. Whereas total bone mass remains relatively stable, the cortical and trabecular bone mass changes extensively. This implies that QCT measurements in the femoral neck depend highly on midneck positioning.


Asunto(s)
Cuello Femoral/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Absorciometría de Fotón/métodos , Anciano , Anciano de 80 o más Años , Densidad Ósea , Femenino , Humanos , Técnicas In Vitro , Masculino
18.
J Anat ; 189 ( Pt 3): 677-82, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8982844

RESUMEN

The purpose of this study was to correlate the in vivo endoanal MRI findings of the anal sphincter with the cross-sectional anatomy and histology. Fourteen patients with rectal tumours were examined with a rigid endoanal MR coil before undergoing abdominoperineal resection. In addition, 12 cadavers were used to obtain cross-sectional anatomical sections. The images were correlated with the histology and anatomy of the resected rectal specimens as well as with the cross-sectional anatomical sections of the 12 cadavers. The findings in 8 patients, 11 rectal preparations, and 10 cadavers, could be compared. In these cases, there was an excellent correlation between endoanal MRI and the cross-sectional cadaver anatomy and histology. With endoanal MRI, all muscle layers of the anal canal wall, comprising the internal anal sphincter, longitudinal muscle, the external anal sphincter and the puborectalis muscle were clearly visible. The levator ani muscle and ligamentous attachments were also well demonstrated. The perianal anatomical spaces, containing multiple septae, were clearly visible. In conclusion, endoanal MRI is excellent for visualising the anal sphincter complex and the findings show a good correlation with the cross-sectional anatomy and histology.


Asunto(s)
Canal Anal/anatomía & histología , Imagen por Resonancia Magnética , Adulto , Anciano , Anciano de 80 o más Años , Anatomía Transversal , Femenino , Humanos , Masculino , Persona de Mediana Edad
19.
Bone ; 19(4): 395-9, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8894146

RESUMEN

The present randomized, double-blind, placebo-controlled, 2-year study is the first to evaluate the effect of 1.25 and 2.5 mg tibolone daily oral administration on trabecular and cortical bone loss in early postmenopausal women. Ninety-four healthy, normal weight, nonsmoking women participated 1-3 years following spontaneous menopause. Twenty-three subjects were randomized to the placebo group, 36 to the 1.25 mg/day tibolone group, and 35 to the 2.5 mg/day tibolone group. Bone density was assessed at 6 month intervals. Spinal trabecular bone density (BD) was measured with quantitative computed tomography. Phalangeal cortical BD was measured by radiographic absorptiometry. The 2-year change vs. baseline in the placebo group for trabecular BD was -6.4% (95% confidence interval -8.1 to -4.7). Cortical BD did not change significantly. At 24 months both tibolone groups showed a statistically significantly higher trabecular [9.4% (6.6-12.2) for the 1.25 mg group and 14.7% (11.8-17.5%) for the 2.5 mg group] and phalangeal BD [4.4% (1.5-7.4) for the 1.25 mg group and 6.8% (3.8-9.8) for the 2.5 mg group] as compared to the placebo group. After 2 years of tibolone in both regimes, trabecular and phalangeal BD was significantly higher as compared to pretreatment values. At 24 months the 2.5 mg group showed a significantly higher trabecular (p < 0.001) but not phalangeal (p = 0.064) BD compared to the 1.25 mg group. Tibolone prevents early postmenopausal bone loss by inducing an increase in trabecular and phalangeal BD.


Asunto(s)
Anabolizantes/uso terapéutico , Densidad Ósea/efectos de los fármacos , Norpregnenos/uso terapéutico , Osteoporosis Posmenopáusica/prevención & control , Absorciometría de Fotón , Anabolizantes/administración & dosificación , Anabolizantes/farmacología , Análisis de Varianza , Biomarcadores/sangre , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Norpregnenos/administración & dosificación , Norpregnenos/farmacología , Osteoporosis Posmenopáusica/tratamiento farmacológico
20.
Osteoporos Int ; 6(1): 25-30, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8845596

RESUMEN

Bone mineral measurements with quantitative computed tomography (QCT) and dual-energy X-ray absorptiometry (DXA) were compared with chemical analysis (ChA) to determine (1) the accuracy and (2) the influence of bone marrow fat. Total bone mass of 19 human femoral necks in vitro was determined with QCT and DXA before and after defatting. ChA consisted of defatting and decalcification of the femoral neck samples for determination of bone mineral mass (BmM) and amount of fat. The mean BmM was 4.49 g. Mean fat percentage was 37.2% (23.3%-48.5%). QCT, DXA and ChA before and after defatting were all highly correlated (r > 0.96, p < 0.0001). Before defatting the QCT values were on average 0.35 g less than BmM and the DXA values were on average 0.65 g less than BmM. After defatting, all bone mass values increased; QCT values were on average 0.30 g more than BmM and DXA values were 0.29 g less than BmM. It is concluded that bone mineral measurements of the femoral neck with QCT and DXA are highly correlated with the chemically determined bone mineral mass and that both techniques are influenced by the femoral fat content.


Asunto(s)
Densidad Ósea/fisiología , Médula Ósea/química , Cuello Femoral/fisiología , Lípidos/análisis , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos X
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