Left common iliac vein compression identified by vascular ultrasonography in asymptomatic women: does standing position influence diagnosis?

BACKGROUND: Vascular ultrasonography is the imaging exam of choice for initial screening for left common iliac vein compression, which is an asymptomatic finding that can be detected in up to 25% of some patient samples. OBJECTIVE: To determine, using vascular ultrasonography, whether findings of left common iliac vein compression in asymptomatic women are different when assessed in the prone and standing positions. METHODS: This is a cross-sectional observational study of 50 adult female volunteers with no symptoms of pelvic venous compression. The parameters assessed with vascular ultrasonography in the prone and standing positions were diameters and maximum velocities of the left common iliac vein at the point at which it crosses behind the right common iliac artery and before this point, in addition to left common iliac vein velocity indices at the crossing. RESULTS: Eight cases of significant compression of the left common iliac vein were identified when assessed in prone position (16%) and just two cases (4%) were identified in the standing position. Left common iliac vein diameters were statistically larger (p = 0.002) at the point where it crosses behind the right common iliac artery in the standing position and velocities and velocity indices were statistically higher (p < 0.001) in the prone position. No significant compression of the left common iliac vein was identified in the standing position when velocity indices were normal in the prone position. CONCLUSIONS: There was no difference in detection of significant compression of the left common iliac vein when assessed in the standing position in comparison with assessment in the prone position. However, the study showed that anatomic compression of the left common iliac vein may be reduced in the standing position.

Bilateral anterior tibial artery entrapment by the ankle extensor retinaculum: case report.

Vascular entrapment is rare. In the lower limbs it is generally asymptomatic, but may cause atypical intermittent claudication in young people without risk factors for atherosclerosis and inflammatory diseases. The most common type of compression involves the popliteal artery, causing symptoms in the region of the infra-patellar muscles. When discomfort is more distal, other entrapment points should be considered, such as the anterior tibial artery. This article reports the case of a patient with intermittent claudication in both feet due to extrinsic compression of the anterior tibial artery bilaterally by the extensor retinaculum of the ankle, diagnosed by vascular ultrasonography and angiotomography during plantar flexion maneuvers. The patient was treated surgically, resulting in improvement of clinical symptoms.

Location and hemodynamic role of perforating veins independent of saphenous veins.

BACKGROUND: The perforating veins of the lower limbs (LL) have valves that enable the blood flow to be directed from the superficial vein system to the deep vein system and they may or may not be connected to the saphenous vein system. OBJECTIVES: To use vascular ultrasonography (VUS) to identify the frequency, location, caliber, and hemodynamic role of perforating veins that do not connect to saphenous veins, during preoperative mapping of LL varicose veins. METHODS: A cross-sectional study was conducted using VUS in women to study the frequency, location, distance from the sole of the foot, and hemodynamic role of perforating veins. RESULTS: The frequencies of perforating veins independent of the saphenous veins were 92.6%, 5.1%, and 2.3%, in the leg, thigh, and knee, respectively, and 25.2% of them were incompetent while 72.3% were drainage veins. The mean diameters of perforating veins were 2.9 mm, 3.5 mm, and 3.7 mm, in the leg, thigh, and knee, respectively. Perforating veins were located at mean distances of 23.8 cm, 43.6 cm, and 59.4 cm above the sole of the foot in the leg, knee, and thigh, respectively. Perforating veins with reflux had a mean caliber of 3.5 mm, irrespective of location. CONCLUSIONS: Perforating veins independent of the saphenous veins are most frequent in the leg, draining reflux from tributary veins. Irrespective of location, perforating veins with reflux had mean caliber of 3.5 mm.

Proposal for computer-aided diagnosis based on ultrasound images of the kidney: is it possible to compare shades of gray among such images?

OBJECTIVE: To compare ultrasound images of the kidney obtained, randomly or in a controlled manner (standardizing the physical aspects of the ultrasound system), by various professionals and with different devices. MATERIALS AND METHODS: We evaluated a total of 919 images of kidneys, obtained by five professionals using two types of ultrasound systems, in 24 patients. The images were categorized into four types, by how they were acquired and processed. We compared the gray-scale median and different gray-scale ranges representative of virtual histological tissues. RESULTS: There were statistically significant differences among the five professionals, regardless of the type of ultrasound system employed, in terms of the gray-scale medians for the images obtained (p < 2.2e-16). Analyzing the four categories of images-a totally random image (without any standardization); a standardized image (with fixed values for gain, time gain control, and dynamic range); a normalized version of the random image; and a normalized version of the standardized image-we determined that the random image, even after normalization, differed quite significantly among the professionals (p = 0.006098). The analysis of the normalized version of the standardized image did not differ significantly among the professionals (p = 0.7319). CONCLUSION: Our findings indicate that a gray-scale analysis of ultrasound images of the kidney performs better when the image acquisition process is standardized and the images undergo a process of normalization.

OBJETIVO: Comparar imagens renais ultrassonográficas obtidas de maneira aleatória e controlada (padronizando fatores físicos do aparelho de ultrassom) por diferentes profissionais e aparelhos. MATERIAIS E MÉTODOS: Foram obtidos quatro tipos de imagens, de acordo com sua aquisição e processamento por cinco profissionais e dois tipos de aparelhos de ultrassonografia, em 24 pacientes, totalizando 919 imagens. Comparamos a mediana de escala de cinza e diferentes intervalos de tons de cinza representantes de tecidos histológicos virtuais. RESULTADOS: As medianas de escala de cinza de imagens renais obtidas por dois tipos de aparelhos foram estatisticamente diferentes (p < 2.2e-16). Analisando os quatro tipos de imagens, partindo de uma totalmente aleatória (sem qualquer padronização), uma padronizada (fixado o ganho, time gain control e dynamic range), e essas duas passando por um processo de normatização, obteve-se que a imagem aleatória é totalmente diversa entre os profissionais (p = 0,006098), mesmo passando pelo processo de normatização. A imagem padronizada, após passar pelo processo de normatização, apresentou resultados equivalentes, não possuindo diferença estatística (p = 0,7319). CONCLUSÃO: Constatou-se que na análise de tons de cinza deve-se usar um mesmo tipo de máquina e uma imagem em que sejam padronizados aspectos físicos, passando por um processo de normatização/padronização.

Absence of right common carotid artery in a patient with common origin of the innominate artery and left common carotid artery.

A 50-year-old woman was referred to the noninvasive vascular laboratory for carotid artery evaluation because of a bruit in the neck. Color Doppler ultrasound examination demonstrated absence of the right common carotid artery and parallel internal and external carotid arteries originating at the brachiocephalic trunk. Computed tomography angiography further described anomalous anatomy, demonstrating a common origin of the innominate artery and left common carotid artery. Knowledge of such unusual anatomy may become valuable in future evaluation or treatment of this patient.

Foam sclerotherapy for lower-limb varicose veins: impact on saphenous vein diameter.

OBJECTIVE: To assess changes in the great saphenous vein (GSV) after foam sclerotherapy for varicose veins. MATERIALS AND METHODS: This was a prospective study of 33 patients who were treated with polidocanol foam sclerotherapy after having had varicose veins with a clinical severity-etiology-anatomy-pathophysiology classification of C4-C6 for three months. The patients were evaluated by ultrasound before, during, and after the procedure (on post-procedure days 7, 15, 30, 60, and 90). The GSV diameter, the rate of venous occlusion, and the rate of reflux elimination were determined. Two patients were excluded for having a history of deep vein thrombosis history, and one was excluded for having bronchial asthma. RESULTS: Thirty patients (26 females and 4 males, with mean age of 62 years) completed the protocol. The mean pre-procedure GSV diameter was 6.0 ± 0.32 mm (range, 3.6-11.2 mm). During the sclerotherapy, the mean GSV diameter was reduced to 1.9 ± 0.15 mm (range, 0.6-3.8 mm). On post-procedure day 7, the mean GSV diameter increased to 6.3 ± 0.28 mm (range, 3.9-9.7 mm). On post-procedure day 90, the mean GSV diameter was 4.0 ± 0.22 mm (range, 1.9-8.2 mm). The rate of GSV reflux was significantly lower in the assessment performed on post-procedure day 90 than in the pre-procedure assessment (p < 0.0028). CONCLUSION: On the basis of our ultrasound analysis, we can conclude that foam sclerotherapy for varicose veins results in a significant reduction in GSV diameter, as well as in the elimination of GSV reflux.

Proposal for computer-aided diagnosis based on ultrasound images of the kidney: is it possible to compare shades of gray among such images? / Proposição de um diagnóstico auxiliado por computador de imagem renal ultrassonográfica: é possível comparar tons de cinza das imagens ultrassonográficas renais?

Abstract Objective: To compare ultrasound images of the kidney obtained, randomly or in a controlled manner (standardizing the physical aspects of the ultrasound system), by various professionals and with different devices. Materials and Methods: We evaluated a total of 919 images of kidneys, obtained by five professionals using two types of ultrasound systems, in 24 patients. The images were categorized into four types, by how they were acquired and processed. We compared the gray-scale median and different gray-scale ranges representative of virtual histological tissues. Results: There were statistically significant differences among the five professionals, regardless of the type of ultrasound system employed, in terms of the gray-scale medians for the images obtained (p < 2.2e-16). Analyzing the four categories of images-a totally random image (without any standardization); a standardized image (with fixed values for gain, time gain control, and dynamic range); a normalized version of the random image; and a normalized version of the standardized image-we determined that the random image, even after normalization, differed quite significantly among the professionals (p = 0.006098). The analysis of the normalized version of the standardized image did not differ significantly among the professionals (p = 0.7319). Conclusion: Our findings indicate that a gray-scale analysis of ultrasound images of the kidney performs better when the image acquisition process is standardized and the images undergo a process of normalization.

Resumo Objetivo: Comparar imagens renais ultrassonográficas obtidas de maneira aleatória e controlada (padronizando fatores físicos do aparelho de ultrassom) por diferentes profissionais e aparelhos. Materiais e Métodos: Foram obtidos quatro tipos de imagens, de acordo com sua aquisição e processamento por cinco profissionais e dois tipos de aparelhos de ultrassonografia, em 24 pacientes, totalizando 919 imagens. Comparamos a mediana de escala de cinza e diferentes intervalos de tons de cinza representantes de tecidos histológicos virtuais. Resultados: As medianas de escala de cinza de imagens renais obtidas por dois tipos de aparelhos foram estatisticamente diferentes (p < 2.2e-16). Analisando os quatro tipos de imagens, partindo de uma totalmente aleatória (sem qualquer padronização), uma padronizada (fixado o ganho, time gain control e dynamic range), e essas duas passando por um processo de normatização, obteve-se que a imagem aleatória é totalmente diversa entre os profissionais (p = 0,006098), mesmo passando pelo processo de normatização. A imagem padronizada, após passar pelo processo de normatização, apresentou resultados equivalentes, não possuindo diferença estatística (p = 0,7319). Conclusão: Constatou-se que na análise de tons de cinza deve-se usar um mesmo tipo de máquina e uma imagem em que sejam padronizados aspectos físicos, passando por um processo de normatização/padronização.

Identificação pela ultrassonografia vascular da compressão da veia ilíaca comum esquerda em mulheres assintomáticas: ortostatismo pode influenciar o diagnóstico? / Left common iliac vein compression identified by vascular ultrasonography in asymptomatic women: does standing position influence diagnosis?

Resumo Contexto A ultrassonografia vascular é o exame de imagem de escolha para rastreamento inicial da compressão na veia ilíaca comum esquerda, cujo achado assintomático pode ser encontrado em até 25% em algumas casuísticas. Objetivo Identificar, pela ultrassonografia vascular, se há diferença na avaliação da compressão na veia ilíaca comum esquerda em mulheres assintomáticas em decúbito dorsal e ao ortostatismo. Métodos Trata-se de um estudo observacional transversal em 50 mulheres voluntárias, sem sintomas de compressão venosa pélvica. Os parâmetros avaliados pela ultrassonografia vascular em decúbito dorsal e ao ortostatismo foram os diâmetros e as velocidades máximas na veia ilíaca comum esquerda no local do cruzamento com a artéria ilíaca comum direita e antes desse cruzamento, além dos índices de velocidade na veia ilíaca comum esquerda no local do cruzamento. Resultados Foram identificados oito casos de compressão significativa na veia ilíaca comum esquerda na avaliação em decúbito dorsal (16%) e somente dois casos (4%) ao ortostatismo. Os diâmetros na veia ilíaca comum esquerda foram estatisticamente maiores (p = 0,002) no local de cruzamento com a artéria ilíaca comum direita ao ortostatismo, e as velocidades e índices de velocidades foram estatisticamente maiores (p < 0,001) em decúbito dorsal. Não houve identificação de compressão significativa na veia ilíaca comum esquerda em ortostatismo quando os índices de velocidades estavam normais em decúbito dorsal. Conclusão Não houve diferença na detecção de compressão significativa da veia ilíaca comum esquerda ao ortostatismo em relação ao decúbito dorsal; no entanto, o estudo mostrou que pode haver menor compressão anatômica da veia ilíaca comum esquerda em posição ortostática.

Abstract Background Vascular ultrasonography is the imaging exam of choice for initial screening for left common iliac vein compression, which is an asymptomatic finding that can be detected in up to 25% of some patient samples. Objective To determine, using vascular ultrasonography, whether findings of left common iliac vein compression in asymptomatic women are different when assessed in the prone and standing positions. Methods This is a cross-sectional observational study of 50 adult female volunteers with no symptoms of pelvic venous compression. The parameters assessed with vascular ultrasonography in the prone and standing positions were diameters and maximum velocities of the left common iliac vein at the point at which it crosses behind the right common iliac artery and before this point, in addition to left common iliac vein velocity indices at the crossing. Results Eight cases of significant compression of the left common iliac vein were identified when assessed in prone position (16%) and just two cases (4%) were identified in the standing position. Left common iliac vein diameters were statistically larger (p = 0.002) at the point where it crosses behind the right common iliac artery in the standing position and velocities and velocity indices were statistically higher (p < 0.001) in the prone position. No significant compression of the left common iliac vein was identified in the standing position when velocity indices were normal in the prone position. Conclusions There was no difference in detection of significant compression of the left common iliac vein when assessed in the standing position in comparison with assessment in the prone position. However, the study showed that anatomic compression of the left common iliac vein may be reduced in the standing position.

Síndrome do aprisionamento da artéria tibial anterior bilateral pelo retináculo extensor do tornozelo: relato de caso / Bilateral anterior tibial artery entrapment by the ankle extensor retinaculum: case report

Resumo Os aprisionamentos vasculares são raros. Nos membros inferiores, geralmente são assintomáticos, mas podem causar claudicação intermitente atípica em indivíduos jovens sem fatores de risco para aterosclerose ou doenças inflamatórias. O vaso mais frequentemente acometido é a artéria poplítea, causando a síndrome do aprisionamento da artéria poplítea (SAAP), com sintomas na região dos músculos infrapatelares. Quando o desconforto ao esforço é mais distal, deve-se pensar em outros locais de aprisionamento arterial, como a artéria tibial anterior. Neste trabalho, é relatado o caso de um paciente com claudicação intermitente nos pés devido ao aprisionamento da artéria tibial anterior (AATA) bilateral, causado pelo retináculo dos músculos extensores e diagnosticado pela ultrassonografia vascular e angiotomografia durante flexão plantar. O paciente foi tratado cirurgicamente, evoluindo com melhora dos sintomas clínicos.

Abstract Vascular entrapment is rare. In the lower limbs it is generally asymptomatic, but may cause atypical intermittent claudication in young people without risk factors for atherosclerosis and inflammatory diseases. The most common type of compression involves the popliteal artery, causing symptoms in the region of the infra-patellar muscles. When discomfort is more distal, other entrapment points should be considered, such as the anterior tibial artery. This article reports the case of a patient with intermittent claudication in both feet due to extrinsic compression of the anterior tibial artery bilaterally by the extensor retinaculum of the ankle, diagnosed by vascular ultrasonography and angiotomography during plantar flexion maneuvers. The patient was treated surgically, resulting in improvement of clinical symptoms.

Vascular color Doppler ultrasound for assessing renovascular hypertension: accuracy of the direct technique for assessing the renal arteries.

OBJECTIVE: To assess the accuracy of vascular color Doppler ultrasound as compared with digital subtraction arteriography for identifying hemodynamically significant renal artery stenoses. METHODS: One hundred and thirty-seven renal arteries from 69 adult patients suspected of having renovascular arterial hypertension were prospectively studied with ultrasound. The results obtained were compared in a double-blind manner with those obtained on digital subtraction arteriography, and the following parameters were calculated according to previously defined criteria: sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy. RESULTS: The inconclusive results (7 arteries) were excluded. The comparison of the 2 methods in regard to the 130 remaining arteries showed concordant results for 116 (89.2%) arteries and discordant results for 14 (10.8%) arteries. The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of vascular color Doppler ultrasound were, respectively, 95.33%, 88.14%, 89.86%, 94.55%, and 91.94%. CONCLUSION: A good correlation between the 2 examinations was observed in the evaluation of the hemodynamically significant renal artery stenoses, making vascular color Doppler ultrasound a noninvasive method useful for selecting patients with suspected renovascular hypertension.

O Uso do Role-Play no Ensino da Técnica de Anamnese e de Habilidades de Comunicação para Estudantes de Medicina / The Use of Role-Play in Teaching Anamnesis Technique and Communication Skills for Medical Students

RESUMO Contexto Comunicação adequada é uma habilidade clínica e, portanto, deve fazer parte dos currículos nas escolas médicas. Várias técnicas podem ser empregadas para ensinar habilidades de comunicação aos estudantes de Medicina. Objetivo Relatar experiência baseada na utilização da técnica de role-play na aprendizagem e satisfação dos estudantes de Medicina na realização da entrevista médica. Métodos Estudo transversal com alunos da disciplina de Semiologia em três etapas distintas: entendimento da teoria, aplicação prática na simulação por representação de papéis (role-play) entre os alunos e gravação de vídeo com pacientes internados no hospital.O desempenho dos estudantes no role-play e no vídeo gravado foi avaliado com base em instrumento adaptado do Guia Calgary-Cambridge. Também foi realizada uma pesquisa de satisfação com os estudantes no final do semestre. Resultados Foram avaliados 30 estudantes, 43% dos quais não foram capazes de detalhar adequadamente os sintomas durante a simulação, porém na gravação do vídeo não apresentaram esta dificuldade. Em relação ao desempenho na simulação e no vídeo, cinco estudantes (16,6%) mantiveram o mesmo desempenho; um estudante (3,3%) apresentou desempenho inferior; e 25 estudantes (83%) apresentaram melhora do desempenho na entrevista com os pacientes em relação à simulação. A grande maioria (92,5%) dos estudantes considerou a atividade útil na sua formação. Conclusão O uso da técnica de role-play no ensino da anamnese apresentou-se como um método de aprendizagem útil e foi bem aceito pelos estudantes de Medicina participantes deste estudo.

ABSTRACT Context Suitable communication is a clinical skill and therefore should be part of the curriculum in medical schools. Several techniques can be used to teach communication skills to medical students. Objective To report an experience based on the role-play technique in the learning process and the satisfaction of medical students in the application of the medical interview. Methods A cross-sectional study with students of the discipline of semiology in three distinct stages related to theory comprehension, practical application with role-play simulation among students and taped interviews with patients in the hospital. Student performance evaluation during simulation and video recording was based on an instrument adapted from the Calgary-Cambridge Guide. A student satisfaction survey was also conducted at the end of the semester. Results Thirty students were evaluated, 43% were not able to adequately detail the symptoms during the simulation but did not present the same difficulty in the taped video. When comparing the simulation and the taped videos exercise 5 students (16.6%) showed the same performance, 1 student (3.3%) displayed a worse performance with the patient interview and 25 students (83%) improved their performance with patients. The vast majority (92.5%) of the students considered the activity useful in their medical training. Conclusion: The use of the role-play technique in the teaching process of anamnesis and in the development of communication skills was demonstrated as a useful learning method and was well accepted by the medical students that participated in this study.

Foam sclerotherapy for lower-limb varicose veins: impact on saphenous vein diameter / Impacto da escleroterapia com espuma no diâmetro da veia safena magna para tratamento de varizes de membros inferiores

Abstract Objective: To assess changes in the great saphenous vein (GSV) after foam sclerotherapy for varicose veins. Materials and Methods: This was a prospective study of 33 patients who were treated with polidocanol foam sclerotherapy after having had varicose veins with a clinical severity-etiology-anatomy-pathophysiology classification of C4-C6 for three months. The patients were evaluated by ultrasound before, during, and after the procedure (on post-procedure days 7, 15, 30, 60, and 90). The GSV diameter, the rate of venous occlusion, and the rate of reflux elimination were determined. Two patients were excluded for having a history of deep vein thrombosis history, and one was excluded for having bronchial asthma. Results: Thirty patients (26 females and 4 males, with mean age of 62 years) completed the protocol. The mean pre-procedure GSV diameter was 6.0 ± 0.32 mm (range, 3.6-11.2 mm). During the sclerotherapy, the mean GSV diameter was reduced to 1.9 ± 0.15 mm (range, 0.6-3.8 mm). On post-procedure day 7, the mean GSV diameter increased to 6.3 ± 0.28 mm (range, 3.9-9.7 mm). On post-procedure day 90, the mean GSV diameter was 4.0 ± 0.22 mm (range, 1.9-8.2 mm). The rate of GSV reflux was significantly lower in the assessment performed on post-procedure day 90 than in the pre-procedure assessment (p < 0.0028). Conclusion: On the basis of our ultrasound analysis, we can conclude that foam sclerotherapy for varicose veins results in a significant reduction in GSV diameter, as well as in the elimination of GSV reflux.

Resumo Objetivo: Avaliar alterações ultrassonográficas na veia safena magna (VSM) após escleroterapia com espuma para varizes. Materiais e Métodos: Estudo prospectivo de 33 pacientes com varizes classificadas como C4-C6 (classificação clinical severity- etiology-anatomy-pathophysiology), durante três meses, submetidos a escleroterapia com espuma de polidocanol. Os pacientes foram acompanhados por ultrassonografia vascular antes, durante e 7, 15, 30, 60 e 90 dias após o procedimento. Avaliaram-se o diâmetro da VSM, a taxa de oclusão venosa e a taxa de abolição do refluxo. Dois indivíduos foram excluídos do estudo por apresentarem história prévia de trombose venosa profunda e um paciente não participou do estudo por asma brônquica. Resultados: Dos 30 pacientes que completaram o protocolo, 26 eram do sexo feminino e 4 eram do sexo masculino, com idade média de 62 anos. O diâmetro da VSM médio pré-operatório foi 6,0 ± 0,32 mm (variação: 3,6-11,2 mm). Na escleroterapia, houve redução do diâmetro médio para 1,9 ± 0,15 mm (variação: 0,6-3,8 mm). Em 7 dias, houve aumento médio do diâmetro da VSM para 6,3 ± 0,28 mm (variação: 3,9-9,7 mm). Em 90 dias, o diâmetro da VSM médio reduziu para 4,0 ± 0,22 mm (variação: 1,9-8,2 mm). O refluxo venoso apresentou redução estatisticamente significante entre o pré-operatório e pós-operatório após 90 dias (p < 0,0028). Conclusão: Com base em nossa análise ultrassonográfica, podemos concluir que a escleroterapia com espuma para varizes resulta em uma redução significativa do diâmetro da VSM, bem como abolição do refluxo da VSM.

Localização e papel hemodinâmico das veias perfurantes independentes das veias safenas / Location and hemodynamic role of perforating veins independent of saphenous veins

As veias perfurantes dos membros inferiores (MMII) apresentam válvulas que permitem o direcionamento do fluxo sanguíneo do sistema venoso superficial para o profundo e podem estar conectadas ou não ao sistema das veias safenas. Objetivos: Identificar, pela ultrassonografia vascular (USV), a frequência, localização, calibre e o papel hemodinâmico das veias perfurantes independentes das veias safenas no mapeamento pré-operatório das varizes dos MMII. Métodos: Foi realizado estudo transversal utilizando a USV em mulheres com o intuito de estudar a frequência, a localização, a altura em relação à base do pé e o papel hemodinâmico das veias perfurantes. Resultados: A frequência de veias perfurantes independentes das veias safenas foi de 92,6%, 5,1% e 2,3%, na perna, coxa e joelho, respectivamente, sendo 25,2% incompetentes e 72,3% de drenagem. O diâmetro médio das veias perfurantes foi de 2,9 mm, 3,5 mm e 3,7 mm, na perna, coxa e joelho, respectivamente. As veias perfurantes localizaram-se em média 23,8 cm, 43,6 cm e 59,4 cm acima da base do pé na perna, joelho e coxa, respectivamente. As veias perfurantes com refluxo apresentaram calibre médio de 3,5 mm, independentemente da localização. Conclusões: As veias perfurantes independentes das veias safenas são mais frequentes na perna, drenando refluxo de veias tributárias. Independentemente da localização, as veias perfurantes com refluxo apresentam calibre médio de 3,5 mm

The perforating veins of the lower limbs (LL) have valves that enable the blood flow to be directed from the superficial vein system to the deep vein system and they may or may not be connected to the saphenous vein system. Objectives: To use vascular ultrasonography (VUS) to identify the frequency, location, caliber, and hemodynamic role of perforating veins that do not connect to saphenous veins, during preoperative mapping of LL varicose veins. Methods: A cross-sectional study was conducted using VUS in women to study the frequency, location, distance from the sole of the foot, and hemodynamic role of perforating veins. Results: The frequencies of perforating veins independent of the saphenous veins were 92.6%, 5.1%, and 2.3%, in the leg, thigh, and knee, respectively, and 25.2% of them were incompetent while 72.3% were drainage veins. The mean diameters of perforating veins were 2.9mm, 3.5mm, and 3.7 mm, in the leg, thigh, and knee, respectively. Perforating veins were located at mean distances of 23.8cm, 43.6 cm, and 59.4 cm above the sole of the foot in the leg, knee, and thigh, respectively. Perforating veins with reflux had a mean caliber of 3.5 mm, irrespective of location. Conclusions: Perforating veins independent of the saphenous veins are most frequent in the leg, draining reflux from tributary veins. Irrespective of location, perforating veins with reflux had mean caliber of 3.5 mm

Profilaxia da trombose venosa profunda em cirurgia bariátrica: estudo comparativo com doses diferentes de heparina de baixo peso molecular / Deep venous thrombosis prevention in bariatric surgery: comparative study of different doses of low weight molecular heparin

Contexto: A cirurgia bariátrica é considerada a melhor opção para o tratamento da obesidade, cujos pacientes são considerados de alto risco para fenômenos tromboembólicos. Objetivos: Comparar o uso de doses diferentes de heparina de baixo peso molecular (HBPM) na profilaxia da trombose venosa profunda (TVP) em pacientes candidatos à cirurgia bariátrica em relação ao risco de TVP, alteração na dosagem do fator anti-Xa e sangramento pré ou pós-operatório. Métodos: Estudo comparativo transversal em pacientes submetidos à cirurgia bariátrica distribuídos em dois grupos, que receberam doses de HBPM de 40 mg (grupo controle, GC) e 80 mg (grupo de estudo, GE). Foram avaliados por ultrassonografia vascular e dosagem de KPTT, TAP, plaquetas e fator anti-Xa. Resultados: Foram avaliados 60 pacientes, sendo 34 no GC e 26 no GE. Foi observada diferença significativa somente no peso (p = 0,003) e índice de massa corporal (p = 0,018) no GE em relação ao GC. Não houve diferença na dosagem de KPTT, TAP, plaquetas e fator anti-Xa entre os grupos. Não foram detectados TVP ou sangramentos significativos em ambos os grupos. Conclusões: Não houve diferença estatisticamente significativa na utilização de doses maiores de HBPM na profilaxia da TVP em pacientes candidatos à cirurgia bariátrica em relação ao risco de TVP, dosagem do fator anti-Xa e sangramento pré ou pós-operatório

Background: Bariatric surgery is considered the best treatment option for patients with obesity who are classed as high risk for thromboembolic events. Objectives: To compare two different doses of low weight molecular heparin (LWMH) for prevention of deep venous thrombosis (DVT) in candidates for bariatric surgery, in terms of DVT risk, abnormal anti-Xa levels, and preoperative and/or postoperative bleeding. Methods: A cross-sectional comparative study of bariatric surgery patients divided into two groups given different doses of LWMH; 40 mg of LWMH (control group, CG) and 80 mg of LWMH (study group, SG), both evaluated by vascular ultrasonography (VU) and according to the results of PTT, PT, platelets, and anti-Xa factor assays. Results: Sixty patients were evaluated, 34 in the CG and 26 in the SG. The only significant differences between the patients in the SG and the CG were weight (p = 0.003) and body mass index (p = 0.018). There were no differences between the groups in PTT, PT, platelets, or anti-Xa factor levels. There was no DVT or significant bleeding in either group. Conclusions: There were no statistical differences when higher doses of LWMH were used for prevention of DVT in bariatric surgery patients, in terms of DVT risk, anti-Xa factor levels, or preoperative and postoperative bleeding

Ultrasound tissue characterization of the normal kidney.

AIM: Ultrasound tissue characterization (USTC) is a precursor of ultrasound virtual histology (USVH), already applied to B-mode images of coronary, carotid, and peripheral arteries, as well as venous thrombosis. Elevated echogenicity has been described for a rejected transplanted kidney. We analyzed data from healthy young adults as reference for further renal USTC. METHODS: Ultrasound kidney images of 10 volunteers were analyzed. Pixel brightness in the 0-to-255 range was rescaled to zero for black and 200 for fascia brightness before automatic classification into 14 ranges, including "blood-like" (0-4), "fat-like" (8-26), "hypoechoic muscle-like" (41-60), "hyperechoic muscle-like" (61-76), 4 ranges of "fiber-like" (112-196), "calcium-like" (211-255) and intermediary intervals. Nomenclature was readapted using nonechoic, hypoechoic I to IV, echoic I to IV, hyperechoic I to IV, and saturated echoes to avoid inference to actual kidney tissue. Descriptive and comparative statistics were based on percentages of pixels in specific brightness ranges. SAMPLE POPULATION: Eight women and 2 men, 26 ± 4 years (range, 22-34 years) old, were studied. Kidney length was 10.5 ± 0.9 cm (9.0-12.0 cm). Doppler US resistivity index was 0.67 ± 0.03 (0.62-0.71). RESULTS: Original fascia brightness converted to 200 value had a mean ± SD of 206 ± 16 (range, 181-236). Kidney grayscale median averaged 37 ± 6 (27-48). Most pixels were hypoechoic II to IV (8-60), averaging 78% ± 6% (66%-87%). Percentages for fat-like, intermediary fat/muscle-like, and hypoechoic muscle-like intervals averaged 25%, 28%, and 25%, respectively. CONCLUSIONS: A reference database for USTC/USVH of normal young kidneys was created for future comparisons with transplanted and abnormal kidneys. Normal renal echoes have low brightness. Hyperechoic pixels may represent abnormalities.