RESUMEN
BACKGROUND: Transarterial radioembolization with yttrium-90 (Y-90 TARE) microspheres therapy has demonstrated positive clinical benefits for the treatment of liver metastases from colorectal cancer (lmCRC). This study aims to conduct a systematic review of the available economic evaluations of Y-90 TARE for lmCRC. METHODS: English and Spanish publications were identified from PubMed, Embase, Cochrane, MEDES health technology assessment agencies, and scientific congress databases published up to May 2021. The inclusion criteria considered only economic evaluations; thus, other types of studies were excluded. Purchasing-power-parity exchange rates for the year 2020 ($US PPP) were applied for cost harmonisation. RESULTS: From 423 records screened, seven economic evaluations (2 cost-analyses [CA] and 5 cost-utility-analyses [CUA]) were included (6 European and 1 USA). All included studies (n = 7) were evaluated from a payer and the social perspective (n = 1). Included studies evaluated patients with unresectable liver-predominant metastases of CRC, refractory to chemotherapy (n = 6), or chemotherapy-naïve (n = 1). Y-90 TARE was compared to best supportive care (BSC) (n = 4), an association of folinic acid, fluorouracil and oxaliplatin (FOLFOX) (n = 1), and hepatic artery infusion (HAI) (n = 2). Y-90 TARE increased life-years gained (LYG) versus BSC (1.12 and 1.35 LYG) and versus HAI (0.37 LYG). Y-90 TARE increased the quality-adjusted-life-year (QALY) versus BSC (0.81 and 0.83 QALY) and versus HAI (0.35 QALY). When considering a lifetime horizon, Y-90 TARE reported incremental cost compared to BSC (range 19,225 to 25,320 $US PPP) and versus HAI (14,307 $US PPP). Y-90 TARE reported incremental cost-utility ratios (ICURs) between 23,875 $US PPP/QALY to 31,185 $US PPP/QALY. The probability of Y-90 TARE being cost-effective at £ 30,000/QALY threshold was between 56% and 57%. CONCLUSIONS: Our review highlights that Y-90 TARE could be a cost-effective therapy either as a monotherapy or when combined with systemic therapy for treating ImCRC. However, despite the current clinical evidence on Y-90 TARE in the treatment of ImCRC, the global economic evaluation reported for Y-90 TARE in ImCRC is limited (n = 7), therefore, we recommend future economic evaluations on Y-90 TARE versus alternative options in treating ImCRC from the societal perspective.
Asunto(s)
Neoplasias Colorrectales , Neoplasias Hepáticas , Femenino , Embarazo , Humanos , Análisis Costo-Beneficio , Microesferas , Radioisótopos de Itrio/uso terapéutico , Neoplasias Hepáticas/radioterapiaRESUMEN
BACKGROUND: Transarterial radioembolization (TARE) with yttrium-90 microspheres is a clinically effective therapy for hepatocellular carcinoma (HCC) treatment. This study aimed to perform a systematic review of the available economic evaluations of TARE for the treatment of HCC. METHODS: The Preferred Reported Items for Systematic reviews and Meta-Analyses guidelines was followed by applying a search strategy across six databases. All studies identified as economic evaluations with TARE for HCC treatment in English or Spanish language were considered. Costs were adjusted using the 2020 US dollars based on purchasing-power-parity ($US PPP). RESULTS: Among 423 records screened, 20 studies (6 cost-analyses, 3 budget-impact-analyses, 2 cost-effectiveness-analyses, 8 cost-utility-analyses, and 1 cost-minimization analysis) met the pre-defined criteria for inclusion. Thirteen studies were published from the European perspective, six from the United States, and one from the Canadian perspectives. The assessed populations included early- (n = 4), and intermediate-advanced-stages patients (n = 15). Included studies were evaluated from a payer perspective (n = 20) and included both payer and social perspective (n = 2). TARE was compared with transarterial chemoembolization (TACE) in nine studies or sorafenib (n = 11). The life-years gained (LYG) differed by comparator: TARE versus TACE (range: 1.3 to 3.1), and TARE versus sorafenib (range: 1.1 to 2.53). Of the 20 studies, TARE was associated with lower treatment costs in ten studies. The cost of TARE treatment varied widely according to Barcelona Clinic Liver Cancer (BCLC) staging system and ranged from 1311 $US PPP/month (BCLC-A) to 71,890 $US PPP/5-years time horizon (BCLC-C). The incremental cost-utility ratio for TARE versus TACE resulted in a 17,397 $US PPP/Quality-adjusted-Life-Years (QALY), and for TARE versus sorafenib ranged from dominant (more effectiveness and lower cost) to 3363 $US PPP/QALY. CONCLUSIONS: Economic evaluations of TARE for HCC treatment are heterogeneous. Overall, TARE is a cost-effective short- and long-term therapy for the treatment of intermediate-advanced HCC.
Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Canadá , Carcinoma Hepatocelular/radioterapia , Análisis Costo-Beneficio , Femenino , Humanos , Neoplasias Hepáticas/radioterapia , Microesferas , Embarazo , Sorafenib/uso terapéuticoRESUMEN
PURPOSE: To assess the feasibility of the Sentinel lymph node biopsy (SLNB) technique in cutaneous non-melanoma malignancies. MATERIALS AND METHODS: Nine patients were retrospectively evaluated performing a scintigraphy with 99mTc-nanocolloid. On the day of the surgery, an initial dynamic study and static images were obtained. The first drainage station visualized was considered the sentinel node (SLN). The SLN position was marked on the skin and after a correct localization in the surgical field with a gamma probe the SLN was obtained. Patients of this study have been followed up for 8 to 48 months. RESULTS: Lymphoscintigraphy detected the sentinel node in 88,8 % of our studies (the SLN was not observed in a patient with a Merkel's tumour on the back). The SLN was identified intraoperatively in those patients with positive imaging. Those cases without scintigraphic demonstrated migration were also not found intraoperatively. Histopathological analysis of the SLN showed non metastatic disease and none patient developed metastases or local recurrence in the monitoring period. CONCLUSIONS: Sentinel node biopsy can be applied to certain cutaneous non-melanoma malignancies. In patients with unclear drainage and to avoid unnecessary lymphadenectomy, the technique offers clear advantages. In our study the SLN analysis was related to the clinical progress. A large number of patients should be examined to truly assess the benefit of this technique in this kind of malignancies and to determinate when the technique must be performed.
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Metástasis Linfática/diagnóstico , Biopsia del Ganglio Linfático Centinela , Neoplasias Cutáneas/patología , Adulto , Anciano , Carcinoma/diagnóstico , Carcinoma/diagnóstico por imagen , Carcinoma/secundario , Carcinoma Basocelular/diagnóstico , Carcinoma Basocelular/diagnóstico por imagen , Carcinoma Basocelular/secundario , Carcinoma de Células de Merkel/diagnóstico , Carcinoma de Células de Merkel/diagnóstico por imagen , Carcinoma de Células de Merkel/secundario , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/secundario , Niño , Dermatofibrosarcoma/diagnóstico , Dermatofibrosarcoma/diagnóstico por imagen , Dermatofibrosarcoma/secundario , Reacciones Falso Negativas , Femenino , Humanos , Metástasis Linfática/diagnóstico por imagen , Metástasis Linfática/patología , Masculino , Persona de Mediana Edad , Cintigrafía , Radiofármacos , Estudios Retrospectivos , Biopsia del Ganglio Linfático Centinela/estadística & datos numéricos , Neoplasias Cutáneas/diagnóstico por imagen , Agregado de Albúmina Marcado con Tecnecio Tc 99mRESUMEN
Objetivo. Valorar la utilización de la biopsia selectiva del ganglio centinela (BSGC) en tumores cutáneos no melanoma. Material y métodos. Se evaluaron retrospectivamente 9 pacientes a los que se realizó linfogammagrafía con 99mTc-nanocoloides. El día de la cirugía se obtuvo un estudio dinámico inicial e imágenes estáticas posteriores. El primer ganglio de drenaje visualizado fue considerado como ganglio centinela (GC). La posición del GC fue marcada cutáneamente en varias proyecciones y posteriormente la correcta localización durante la extracción quirúrgica se realizó con sonda de detección externa. El seguimiento de los pacientes osciló entre 8 y 48 meses. Resultados. La linfogammagrafía localizó el ganglio centinela en 88,8 % de los casos. El GC no fue observado en un paciente con un tumor de Merkel localizado en la espalda. El GC fue identificado intraoperatoriamente en los pacientes que presentaron una imagen positiva. En aquellos casos en que no hubo migración gammagráfica tampoco se detectó intraoperatoriamente. La inmunohistopatología mostró adenopatías libres de metástasis, y los pacientes permanecieron sin afectación durante el periodo de seguimiento. Conclusiones. La utilización de la BSGC tiene una potencial aplicación en determinados tumores cutáneos no melanoma. En pacientes con drenaje linfático errático y la capacidad de evitar una linfadenectomía radical terapéutica, ofrece a la técnica destacadas ventajas. La situación del GC fue congruente con la evolución clínica de los pacientes. Sería necesario analizar un mayor número de pacientes para asegurar los beneficios de la técnica con el objeto de determinar los tumores más susceptibles para su realización y el estadio en el cual llevarla a cabo
Purpose. To assess the feasibility of the Sentinel lymph node biopsy (SLNB) technique in cutaneous non-melanoma malignancies. Materials and methods. Nine patients were retrospectively evaluated perfoming a scintigraphy with 99mTc-nanocolloid. On the day of the surgery, an initial dynamic study and static images were obtained. The first drainage station visualized was considered the sentinel node (SLN). The SLN position was marked on the skin and after a correct localization in the surgical field with a gamma probe the SLN was obtained. Patients of this study have been followed up for 8 to 48 months. Results. Lymphoscintigraphy detected the sentinel node in 88,8 % of our studies (the SLN was not observed in a patient with a Merkel's tumour on the back). The SLN was identified intraoperatively in those patients with positive imaging. Those cases without scintigraphic demonstrated migration were also not found intraoperatively. Histopathological analysis of the SLN showed non metastatic disease and none patient developed metastases or local recurrence in the monitoring period. Conclusions. Sentinel node biopsy can be applied to certain cutaneous non-melanoma malignancies. In patients with unclear drainage and to avoid unnecessary lymphadenectomy, the technique offers clear advantages. In our study the SLN analysis was related to the clinical progress. A large number of patients should be examined to truly assess the benefit of this technique in this kind of malignancies and to determinate when the technique must be perfomed
Asunto(s)
Masculino , Femenino , Niño , Adulto , Anciano , Persona de Mediana Edad , Humanos , Biopsia del Ganglio Linfático Centinela/métodos , Neoplasias Cutáneas/patología , Neoplasias Cutáneas , Neoplasias Cutáneas/cirugía , Estudios Retrospectivos , Estudios de SeguimientoRESUMEN
As a first phase in a nationwide multicenter study to obtain myocardial perfusion normality patterns, this work presents the study design and quality control methodology used to guarantee that the gammacameras fulfilled some minimum quality requirements. The following aspects were considered in the study design in order to guarantee the homogeneity and interchangeability of the results: creation and structure of the work group, data interchange system, data selection and acquisition, centralized archiving and processing, assessment system, study acceptance criteria and distribution of the results. To carry out the instrumental quality control, three phantom studies were established, one to control the rotation center, another to verify tomographic uniformity and a third to simulate the shape and orientation of the left ventricle. The three phantoms circulated through all of the 18 participating centers in this project, which corresponded to 19 gammacameras. Very strict guidelines had to be followed in the acquisition and processing of these phantom studies. If any camera and/or center did not fulfill the criteria established, it was advised of the problem detected in order to correct it. Once the defect was repaired, all the phantoms were sent again for verification. Uniformity of the rotation center was quantified by means of the eccentricity of a 360 degrees orbit, admitting up to a maximum of 10%. Tomographic uniformity was visually assessed, taking in account the number of slices with rings and their contrast and finally no artifacts could be present in the reconstructed study of the ventricle. The center of rotation was within limits in all the cameras except one case while the tomographic uniformity was incorrect in 6 cases. All the departments, except one, corrected the defects detected, and passed the acceptance test. The results made it possible to guarantee adequate homogeneity and instrumental quality in this multicenter study.
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Circulación Coronaria , Corazón/diagnóstico por imagen , Compuestos Organofosforados , Compuestos de Organotecnecio , Radiofármacos , Tomografía Computarizada de Emisión de Fotón Único , Diseño de Equipo , Cámaras gamma , Humanos , Selección de Paciente , Control de Calidad , Valores de Referencia , Proyectos de Investigación , España , Tomografía Computarizada de Emisión de Fotón Único/instrumentación , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tomografía Computarizada de Emisión de Fotón Único/normasRESUMEN
This objective of this study was to obtain a pool of Myocardial Perfusion SPECTs with a 99mTetrofosmin stress/rest one day protocol in normal volunteers having a less than or equal to 5% likelihood of coronary artery disease that represents normalcy in the Spanish population. A total of 169 volunteers from 15 hospitals were studied. The volunteers were divided into 5 groups: Groups 1, 2 or 3 corresponding to men < 30 years (n = 33), men between 30 and 50 years (n = 32), or men > 50 years (n = 31); Groups 4 or 5: premenopausal (n = 38) or postmenopausal women (n = 35). A clinical history, physical examination, clinical laboratory parameters, echocardiography and a symptom limited exercise stress test were performed in all of them and had to be normal. The mean likelihood of coronary artery disease was 1.15 +/- 1.07%.Twenty-four segments were analyzed in each study and were classified into 5 grades of uptake (1 = normal, 2, 3, 4 = mild, moderate or severe defect and 5 = no uptake). Defects were then analyzed according to sex and location. Considering the stress and rest studies separately (8,112 segments), only 19 moderate and 75 mild defects were found, these corresponding to 16 volunteers, with more inferior defects in men and anterior defects in women. These data validate the normalcy of our population. A pool of Myocardial Perfusion SPECTs with a 99mTetrofosmin stress/rest one day protocol in normal volunteers that represents Spanish normal values was obtained.
Asunto(s)
Circulación Coronaria , Corazón/diagnóstico por imagen , Compuestos Organofosforados , Compuestos de Organotecnecio , Radiofármacos , Tomografía Computarizada de Emisión de Fotón Único , Adulto , Factores de Edad , Anciano , Femenino , Pruebas de Función Cardíaca , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Selección de Paciente , Posmenopausia , Premenopausia , Valores de Referencia , Factores de Riesgo , Caracteres Sexuales , EspañaRESUMEN
Como primera fase de un estudio multicéntrico para la obtención de patrones de normalidad de perfusión miocárdica, en este trabajo se presenta el diseño del estudio y la metodología de control de calidad empleada para garantizar que las gammacámaras cumplieran con unos requisitos mínimos de calidad. En el diseño del estudio se han considerado los siguientes aspectos a fin de garantizar la homogeneidad e intercambiabilidad de resultados: creación y estructuración de un grupo de trabajo, sistema para el intercambio de datos, selección y adquisición de datos, registro y procesado centralizado de los estudios, sistema de valoración y criterios de aceptación de los estudios y la distribución de resultados. Para el control de calidad de la instrumentación se construyeron tres maniquíes, uno para el control del centro de rotación, otro para la comprobación de la uniformidad tomográfica y un tercero que simulaba la forma y posición del ventrículo izquierdo. Los tres maniquíes circularon por todos los centros participantes en este proyecto (18) que correspondían a 19 cámaras, debiendo seguir unas normas estrictas para su utilización. Si algún equipo no cumplía con los criterios establecidos el centro correspondiente era avisado del problema detectado para que procediera a su rectificación. Un vez reparado el defecto se volvía a enviar el conjunto de maniquíes para su verificación. La constancia del centro de rotación se cuantificó midiendo la excentricidad de la órbita, admitiéndose hasta un máximo de 10 por ciento. La uniformidad tomográfica se valoró visualmente teniendo en cuenta tanto el número de cortes con presencia de anillos como su contraste. En las imágenes del maniquí de ventrículo se comprobó la ausencia de artefactos. El centro de rotación fue correcto en todas las gammacámaras excepto en una mientras que la uniformidad tomográfica presento defectos en 6 casos. El maniquí de ventrículo fue siempre correcto. Todos los centros, excepto uno, corrigieron los defectos detectados por lo que pasaron la prueba de aceptación. Los resultados permitieron garantizar la adecuada homogeneidad y calidad instrumental de los estudios generados en este estudio multicéntrico. (AU)
Asunto(s)
Humanos , Tomografía Computarizada de Emisión de Fotón Único , Circulación Coronaria , España , Compuestos de Organotecnecio , Cámaras gamma , Selección de Paciente , Radiofármacos , Compuestos Organofosforados , Proyectos de Investigación , Control de Calidad , Valores de Referencia , Diseño de Equipo , CorazónRESUMEN
El objetivo fue obtener un número suficiente de Tomogammagrafías Miocárdicas de Perfusión en voluntarios presumiblemente normales, con una probabilidad pretest de padecer enfermedad coronaria menor del 5 por ciento, siguiendo un protocolo corto esfuerzo/reposo con 99mTc-Tetrofosmina, con el fin de constituir un conjunto de estudios de normalidad representativo de la población española. Se estudiaron 169 voluntarios, pertenecientes a 15 centros, divididos en 5 grupos: Grupos 1, 2 y 3 correspondiendo a: varones menores de 30 años (n = 33), entre 30 y 50 años (n = 32) o mayores de 50 años (n = 31); Grupos 4 y 5: mujeres premenopáusicas (n = 38) o postmenopáusicas (n = 35). A todos ellos se les historió y realizó examen físico completo, analítica general, ecocardiografía y prueba de esfuerzo máxima limitada por síntomas, que debieron ser normales. El promedio de la probabilidad pretest de padecer enfermedad coronaria fue de 1,15 ñ 1,07 por ciento. En cada tomogammagrafía se analizaron 24 segmentos que se clasificaron según su captación (1 = normal, 2, 3, 4 = defecto ligero, moderado o severo y 5 = captación nula). Posteriormente, los defectos se agruparon en función del sexo y de su localización. Considerando los estudios en esfuerzo y en reposo (8.112 segmentos), se encontraron únicamente 19 defectos moderados y 75 ligeros, que correspondían a 16 individuos, lo que apoya la 'normalidad' de la muestra estudiada, con una mayor frecuencia de defectos en la pared miocárdica inferior en hombres y anterior en mujeres. Se constituyó un conjunto de estudios de normalidad de Tomogammagrafías miocárdicas de perfusión, siguiendo un protocolo corto esfuerzo/reposo con 99mTc-Tetrofosmina, representativo de la población española (AU)
Asunto(s)
Persona de Mediana Edad , Adulto , Anciano , Masculino , Femenino , Humanos , Tomografía Computarizada de Emisión de Fotón Único , Circulación Coronaria , Factores de Riesgo , España , Compuestos de Organotecnecio , Radiofármacos , Posmenopausia , Selección de Paciente , Premenopausia , Compuestos Organofosforados , Valores de Referencia , Factores de Edad , Estilo de Vida , Corazón , Caracteres Sexuales , Pruebas de Función CardíacaRESUMEN
BACKGROUND: We sought to determine the degree of interhospital agreement in the interpretation of exercise myocardial technetium-99m tetrofosmin single photon emission computed tomography (SPECT). METHODS AND RESULTS: Five experienced hospital laboratories were asked to submit 2 sets of myocardial Tc-99m tetrofosmin SPECT images obtained in 150 patients undergoing coronary angiography: group A used a uniform color scale for all hospitals, and group B used the individual color scale in place at each hospital (uniform color scale, nonuniform color scale, and black-and-white scale). Thus a total of 300 images were interpreted by each center without knowledge of any other patient data. Angiographically significant coronary artery disease (< or =50% diameter stenosis) was present in 90 patients (60%). By a majority decision (3 or more centers), the sensitivity was found to be similar for groups A and B (82% and 84%, respectively), but the specificity was significantly higher for group A (87% vs 73%; P =.021). Four or all 5 of the centers agreed on abnormal or normal results of SPECT images in 87% of patients in group A (kappa 0.626) and in 78% of patients in group B (kappa 0.528). The kappa value of 0.617 was obtained for the uniform color scale, 0.467 for the uniform black-and-white scale, and 0.444 for the nonuniform color scale. Agreement on the left anterior descending artery territory (81% for group A and 78% for group B) was similar to that of the right coronary artery territory (79% for A and 75% for B) and to that of the left circumflex artery territory (91% for A and 85% for B). Agreement was similar in patients with 1-, 2-, and 3-vessel coronary artery disease (91%, 88%, and 86% for group A and 81%, 82%, and 82% for group B, respectively). CONCLUSIONS: In the interpretation of myocardial Tc-99m tetrofosmin SPECT images, good interinstitutional observer agreement was found, mainly when the uniform display method was adopted.
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Prueba de Esfuerzo , Compuestos Organofosforados , Compuestos de Organotecnecio , Radiofármacos , Tomografía Computarizada de Emisión de Fotón Único , Adulto , Anciano , Angiografía Coronaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Sensibilidad y EspecificidadRESUMEN
INTRODUCTION AND OBJECTIVES: The aim of this study is to analyze the impact of clinical data and the interhospital agreement in the interpretation of myocardial perfusion single photon emission tomography (SPECT) images and polar mapping. METHODS: 150 patients from 5 hospitals were studied. Each center contributed with tomographic images and polar maps of 99mTc-tetrofosmin exercise SPECT and clinical reports of 30 patients. Thus, 300 images (150 of tomographic images and 150 of polar maps) were interpreted by each center without knowledge of clinical data of the patient ("blinded" report). RESULTS: 90 (60%) out of 150 patients had a coronary stenosis > or = 50%. Sensitivity and specificity of "non blinded" report were 91% and 86%, respectively. Sensitivity determined by majority decision (three or more centers) was 82% for tomographic images and 83% for polar maps (p = 0.002 and p = 0.03, respectively, regarding the "non-blinded" report). Specificity was 88% for tomographic images and 79% for polar map (p = 0.05 with respect to tomographic images). Interhospital agreement was good not only for tomographic images (kappa: 0.625) but for polar maps (kappa: 0.7) as well. CONCLUSIONS: Sensitivity of clinical or "non blinded" report of myocardial perfusion SPECT is significantly higher than the "blinded" report. Specificity of the "blinded" report of polar mapping is lower than that of tomographic images. A good interhospital agreement in interpretation of both types of images was observed.
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Corazón/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único/estadística & datos numéricos , Anciano , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/diagnóstico por imagen , Variaciones Dependientes del Observador , Pronóstico , Radiofármacos , Sensibilidad y Especificidad , España , Tomografía Computarizada de Emisión de Fotón Único/métodosRESUMEN
We report a new case of Lyme disease with cardiac manifestations, which has been possible to follow during the long period of 12 years. We have detected the usual ECG abnormalities, and concentric hypertrophic myocardiopathy, by echocardiography. The acute myocarditis was demonstrated by 111In-antimyosin scintigraphy, which showed global myocardial uptake of the tracer, constituting the first report, to our knowledge, of Lyme myocarditis diagnosed by this method.
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Anticuerpos Monoclonales , Radioisótopos de Indio , Enfermedad de Lyme/complicaciones , Miocarditis/diagnóstico por imagen , Miosinas/inmunología , Adulto , Femenino , Humanos , Miocarditis/etiología , CintigrafíaAsunto(s)
Cardiomiopatías/diagnóstico por imagen , Epirrubicina/efectos adversos , Adulto , Anciano , Neoplasias de la Mama/tratamiento farmacológico , Cardiomiopatías/inducido químicamente , Epirrubicina/uso terapéutico , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Cintigrafía , Factores de Riesgo , Volumen Sistólico , Factores de TiempoRESUMEN
The hemodynamic changes induced by spinal cord stimulation (SCS) have been studied in a group of 20 patients with peripheral vascular pain. The surgical technique consisted of the introduction of 1 or 2 electrodes in the subarachnoid space up to the level of the painful area, for mono or bipolar SCS. Several techniques have been used for evaluation of hemodynamic changes induced by SCS. Peripheral blood flow speed was measured by means of ultrasound Doppler, showing a raised maximum speed during stimulation, and a tendency of the pulse wave to return to normal. Thermography showed a marked increase of temperature in the painful area. Preoperatively, plethysmography showed an absence of the typical flow waveform, whilst postoperative recordings showed a small wave of progressively increasing amplitude. Scintigraphy with 201TI showed an increase in muscular blood flow in previously hypovascularized areas. The mechanism of action of SCS on peripheral blood flow and vascular pain is discussed.