Brazilian national bariatric registry - pilot study.

INTRODUCTION: Brazil is a world leader in bariatric surgery. However, the actual number of surgeries performed in the country is still unknown. It is necessary to implement an instrument to monitor the quality of care provided. This study evaluated the implementation of a Bariatric Surgery Data Registry in Brazil. METHODOLOGY: the registry was developed with Dendrite Clinical Systems Ltd., with data collected prospectively on an internet-based software. Seven centers were selected based on surgical volume and data entry commitment. The project covered three years after system implementation. RESULTS: 1,363 procedures performed by 17 surgeons were included. Most patients were female (67.2%), with average age of 39 years old and average baseline BMI of 41.5kg/m2. Diabetes mellitus was present in 34.5%, and hypertension in 40.1%. Roux-en-Y gastric bypass was performed in 79.3%, 95.5% by laparoscopy. There was one in-hospital death of cardiovascular cause. The average hospital stay was 2.03 days. The surgery-related complication rate was 0.97% in the first month, with three reoperations. Short-term follow-up was recorded in 75.6% and one-year follow-up in 21.64%. Total body weight loss was 10% in 30 days, rising to 33.3% after one year, with no difference between surgical techniques. CONCLUSIONS: the population profile was in accordance with the global registry of the International Federation for the Surgery of Obesity and Metabolic Disorders. The main difficulty encountered was low postoperative data entry. The experience acquired in this project will help advance data collection and knowledge of the safety and effectiveness of bariatric surgery in Brazil.

Brazilian national bariatric registry - pilot study / Registro nacional de dados em cirurgia bariátrica - estudo piloto

ABSTRACT Introduction: Brazil is a world leader in bariatric surgery. However, the actual number of surgeries performed in the country is still unknown. It is necessary to implement an instrument to monitor the quality of care provided. This study evaluated the implementation of a Bariatric Surgery Data Registry in Brazil. Methodology: the registry was developed with Dendrite Clinical Systems Ltd., with data collected prospectively on an internet-based software. Seven centers were selected based on surgical volume and data entry commitment. The project covered three years after system implementation. Results: 1,363 procedures performed by 17 surgeons were included. Most patients were female (67.2%), with average age of 39 years old and average baseline BMI of 41.5kg/m2. Diabetes mellitus was present in 34.5%, and hypertension in 40.1%. Roux-en-Y gastric bypass was performed in 79.3%, 95.5% by laparoscopy. There was one in-hospital death of cardiovascular cause. The average hospital stay was 2.03 days. The surgery-related complication rate was 0.97% in the first month, with three reoperations. Short-term follow-up was recorded in 75.6% and one-year follow-up in 21.64%. Total body weight loss was 10% in 30 days, rising to 33.3% after one year, with no difference between surgical techniques. Conclusions: the population profile was in accordance with the global registry of the International Federation for the Surgery of Obesity and Metabolic Disorders. The main difficulty encountered was low postoperative data entry. The experience acquired in this project will help advance data collection and knowledge of the safety and effectiveness of bariatric surgery in Brazil.

RESUMO Introdução: o Brasil é líder mundial em cirurgia bariátrica. No entanto, o número de cirurgias realizadas no país ainda é desconhecido. É necessário um instrumento para monitorar a qualidade da assistência prestada. Este estudo avaliou a implantação de um Registro de Dados de Cirurgia Bariátrica no Brasil. Metodologia: O registro foi desenvolvido com a Dendrite Clinical Systems Ltd., com dados coletados prospectivamente em software na internet. Sete centros foram selecionados, baseado no volume cirúrgico e compromisso de inserção de dados. O projeto abrangeu três anos após implementação. Resultados: foram incluídos 1.363 procedimentos realizados por 17 cirurgiões. A maioria dos pacientes eram mulheres (67,2%), com idade média de 39 anos e IMC basal médio de 41,5kg/m2. Diabetes mellitus estava presente em 34,5% e hipertensão em 40,1%. Bypass gástrico em Y de Roux foi realizado em 79,3%, 95,5% por laparoscopia. Houve um óbito hospitalar de causa cardiovascular. A média de permanência hospitalar foi de 2,03 dias. A taxa de complicações relacionadas à cirurgia foi 0,97% no primeiro mês, com três reoperações. Seguimento de curto prazo foi registrado em 75,6% e de um ano em 21,64%. A perda de peso corporal total foi de 10% em 30 dias, aumentando para 33,3% após um ano, sem diferença entre técnicas cirúrgicas. Conclusões: o perfil populacional está de acordo com o registro global da IFSO. A principal dificuldade encontrada foi a baixa inserção de dados pós-operatórios. A experiência adquirida neste projeto ajudará no conhecimento da segurança e eficácia da cirurgia bariátrica no Brasil.

Good Clinical Practices on Argon Plasma Coagulation Treatment for Weight Regain Associated with Dilated Gastrojejunostomy Following Roux-en-Y Gastric Bypass: a Brazilian-Modified Delphi Consensus.

INTRODUCTION: Argon plasma coagulation (APC) alone is effective and safe at treating weight regain following Roux-en-Y gastric bypass (RYGB). However, technical details of the treatment vary widely among studies. Therefore, we aimed to create good clinical practice guidelines through a modified Delphi consensus, including experts from the collaborative Bariatric Endoscopy Brazilian group. METHODS: Forty-one locally renowned experts were invited to the consensus by email. Experiences of > 150 APC-treated cases or authorship of relevant articles were the eligibility criteria. An initial questionnaire with short-answer questions was distributed to the experts. The organizing committee converted the responses into statements for an online 2-day voting webinar. Consensus was defined as more than 67% of positive answers. Three consecutive voting rounds were planned with discussion and statement refinements between rounds. RESULTS: Thirty-seven experts fulfilled eligibility criteria and attended the live webinar voting. The total number of patients treated by the panel was 12,349. By the third round, all 79 statements reached consensus. The recommendations include the definition of dilated gastrojejunal anastomosis as ≥ 15 mm, minimum regain of 20% of the lost weight to indicate the APC therapy, 6 to 8 weeks as the ideal interval between ablation sessions, and stopping treatment when the stoma reaches < 12 mm of breadth. CONCLUSIONS: This consensus provides several recommendations based on a highly experienced panel of endoscopists. Although it covers most aspects of the treatment, the level of evidence is low for the majority of the statements. Therefore, bariatric endoscopists should be constantly attentive to new evidence on APC treatment.

The "Hug" Technique-Roux-en-Y Gastric Bypass with Preservation of the Posterior Wrap in Patients with Previous Nissen Fundoplication: a Simple Solution for a Complex Problem.

BACKGROUND: Laparoscopic conversion of Nissen Fundoplication to Roux-en-Y gastric bypass (RYGB) is a complex procedure due to increased operative time, morbidity, and length of hospital stay (LOS). In this study, a new simplified technique avoiding the total dismantling of the previous Nissen repair to construct the gastric pouch, the so-called hug technique is presented for the conversion of Nissen fundoplication to RYGB. METHODS: The present study is a prospective single-center clinical series reporting on the feasibility and safety of the "hug" technique for the creation of laparoscopic RYGB. The major innovation of this approach is the fact that the posterior part of the fundoplication wrap is left in place without further dissection or manipulation. The anterior part is stapled and remains attached to the excluded stomach. Prospective data on intraoperative and postoperative morbidity and bariatric outcomes were collected. RESULTS: A total of 44 consecutive patients with a mean body mass index (BMI) of 43.7 kg/m2 (SD = 4.0, range = 35.6-52.0) underwent the "hug" procedure between 2004 and 2015. Mean operative time was 72 min (58-105 min). Morbidity was 4.5%, with no mortality. For patients with follow-up at 3 years, the percentage of total body weight loss (%TBWL) was 32.5%; the excess weight loss (EWL) was 64.2%. CONCLUSION: In contrast to current other techniques of bariatric surgery for patients having previously undergone a Nissen fundoplication, the "hug" procedure to create an RYGB is safe and simple to perform. This technique avoids the deconstruction of the previous repair and is still maintaining anti-reflux anatomy. Nevertheless, there is a need for further studies to evaluate the long-term outcomes of the procedure.

Does weight gain, throughout 15 years follow-up after Nissen laparoscopic fundoplication, compromise reflux symptoms control?

BACKGROUND: Gastroesophageal reflux disease is defined by the abnormal presence of gastric content in the esophagus, with 10% incidence in the Western population, being fundoplication one treatment option. AIM: To evaluate the early (six months) and late (15 years) effectiveness of laparoscopic fundoplication, the long term postoperative weight changes, as well as the impact of weight gain in symptoms control. METHODS: Prospective study of 40 subjects who underwent laparoscopic Nissen's fundoplication. Preoperatively and early postoperatively, clinical, endoscopic, radiologic, manometric and pHmetric evaluations were carried out. After 15 years, clinical and endoscopic assessments were carried out and the results compared with the early ones. The presence or absence of obesity was stratified in both early and late phases, and its influence in the long-term results of fundoplication was studied, measuring quality of life according to the Visick criteria. RESULTS: The mean preoperative ages, weight, and body mass index were respectively, 51 years, 69.67 kg and 25.68 kg/m2. The intraoperative and postoperative complications rates were 12.5% and 15%, without mortality. In the early postoperative period the symptoms were well controlled, hernias and esophagitis disappeared, the lower esophageal sphincter had functional improvement, and pHmetry parameters normalized. In the late follow-up 29 subjects were assessed. During this period there was adequate clinical control of reflux regardless of weight gain. In both time periods Visick criteria improved. CONCLUSION: Fundoplication was safe and effective in early and late periods. There was late weight gain, which did not influence effective symptoms control.

Correction to: Endoscopic Argon Plasma Coagulation Vs. Multidisciplinary Evaluation in the Management of Weight Regain after Gastric Bypass Surgery: a Randomized Controlled Trial with SHAM Group.

In the original article the captions for Figs. 1-3 are incorrect.

Endoscopic Argon Plasma Coagulation vs. Multidisciplinary Evaluation in the Management of Weight Regain After Gastric Bypass Surgery: a Randomized Controlled Trial with SHAM Group.

BACKGROUND: Roux-en-Y gastric bypass is one of the most widely performed bariatric surgeries. However, the relapse of obesity occurs in approximately 20% of patients and enlargement of the anastomosis is one of the factors associated with this relapse. Endoscopic treatment of the anastomosis has been proposed to assist in renewed weight loss. One endoscopic technique is the narrowing of the anastomosis argon plasma coagulation (APC). OBJECTIVE: Evaluate the effectiveness and safety of the endoscopic treatment of an enlarged anastomosis with APC. METHODS: A randomized controlled study was conducted comparing APC to exclusive multidisciplinary management after weight regain. RESULTS: Forty-two patients were divided into two groups: APC (n = 22) and control (n = 20). After 14 months of follow-up with a crossover at 6 months, significant improvement in satiety and greater weight loss were found in the APC group and after crossover. APC was associated with significant weight loss [9.73 (7.46, 12) vs. + 1.38 (- 1.39, 2.15)], a reduction in the anastomosis diameter [p < 0.001], early satiation [0.77 (0.44, 1.11) vs. - 0.59 (- 0.95, - 0.23), p < 0.001], and increased quality of life measured using the EQ5D index [p = 0.04] and EQ5D VAS scale [p = 0.04]. Considering total mean weight loss throughout the entire follow-up, weight loss was similar in both groups (13.02 kg in the APC and 11.52 kg in the control). CONCLUSION: Treatment of the gastrojejunal anastomosis with APC was effective and safe, with significant weight loss, the return of early satiation, and an improvement in quality of life.

Does weight gain, throughout 15 years follow-up after Nissen laparoscopic fundoplication, compromise reflux symptoms control? / O ganho do peso no seguimento de 15 anos após Nissen laparoscópico compromete o controle dos sintomas de refluxo?

ABSTRACT Background: Gastroesophageal reflux disease is defined by the abnormal presence of gastric content in the esophagus, with 10% incidence in the Western population, being fundoplication one treatment option. Aim: To evaluate the early (six months) and late (15 years) effectiveness of laparoscopic fundoplication, the long term postoperative weight changes, as well as the impact of weight gain in symptoms control. Methods: Prospective study of 40 subjects who underwent laparoscopic Nissen's fundoplication. Preoperatively and early postoperatively, clinical, endoscopic, radiologic, manometric and pHmetric evaluations were carried out. After 15 years, clinical and endoscopic assessments were carried out and the results compared with the early ones. The presence or absence of obesity was stratified in both early and late phases, and its influence in the long-term results of fundoplication was studied, measuring quality of life according to the Visick criteria. Results: The mean preoperative ages, weight, and body mass index were respectively, 51 years, 69.67 kg and 25.68 kg/m2. The intraoperative and postoperative complications rates were 12.5% and 15%, without mortality. In the early postoperative period the symptoms were well controlled, hernias and esophagitis disappeared, the lower esophageal sphincter had functional improvement, and pHmetry parameters normalized. In the late follow-up 29 subjects were assessed. During this period there was adequate clinical control of reflux regardless of weight gain. In both time periods Visick criteria improved. Conclusion: Fundoplication was safe and effective in early and late periods. There was late weight gain, which did not influence effective symptoms control.

RESUMO Racional: A doença do refluxo gastroesofágico é definida pela presença anormal do conteúdo gástrico no esôfago com incidência de 10% na população ocidental, sendo a fundoplicatura uma das opções de tratamento. Objetivo: Avaliar a efetividade precoce (seis meses) e tardia (15 anos) da fundoplicatura laparoscópica, bem como a evolução ponderal pós-operatória em longo prazo, e o impacto do ganho de peso no controle tardio dos sintomas. Métodos: Estudo prospectivo com 40 indivíduos submetidos à fundoplicatura laparoscópica pela técnica de Nissen. No pré e pós-operatório precoce, foram realizadas avaliações clínica, endoscópica, radiológica, manométrica e pHmétrica. Após 15 anos, realizaram-se avaliações clínica e endoscópica, comparando-se os resultados com os da fase precoce. Estratificou-se a presença ou ausência de obesidade nestas fases e estudou-se sua influência nos resultados em longo prazo, mensurando-se a qualidade de vida pelos critérios de Visick. Resultados: As médias de idade, peso e do índice de massa corporal pré-operatórias foram 51 anos, 69.67 kg e 25,68 kg/m2. O índice de complicações intra e pós-operatórias foram 12,5% e 15%, sem mortalidade. No pós-operatório precoce houve controle dos sintomas, remissão das hérnias e esofagites, melhora funcional do esfíncter esofágico inferior e normalização dos parâmetros pHmétricos. No seguimento tardio, 29 indivíduos foram acompanhados. Nesta fase, houve adequado controle clínico do refluxo, independente do ganho de peso. Em ambas as fases houve melhora nos critérios de Visick. Conclusão: A fundoplicatura foi segura e efetiva, precoce e tardiamente. Houve ganho de peso tardio, o que não influenciou no controle efetivo dos sintomas.

The Role of Gastrojejunostomy Size on Gastric Bypass Weight Loss.

BACKGROUND: The laparoscopic Roux-en-Y gastric bypass (LRYGB) has been considered a reference procedure in the bariatric surgery. The linear-stapled gastrojejunostomy (GJ) has proved to be safe and effective, but its optimal size referred to postoperative weight loss remains poorly understood. OBJECTIVES: Evaluate the role of the linear-stapled GJ size in the mid-term post-LRYGB weight loss and occurrence of complications. MATERIALS AND METHODS: From January to April 2014, 128 patients underwent LRYGB with linear-stapled GJ in a 2-year follow-up. The LRYGB were carried out with the same technical steps, except for the length of the GJ. In GJ-15-mm group (n = 64), the GJ was constructed with white 45-mm cartridge in an extension of only 15 mm whereas in GJ-45-mm group (n = 64), the GJ was achieved using full extension of the cartridge. The body mass index (BMI) reduction was recorded for 24 months after procedure. RESULTS: The mean ages were 38 ± 10.6 and 41.3 ± 12.3 years, and there were 45 (70.3%) and 51 (79.7%) females in the GJ-15-mm and GJ-45-mm groups, respectively. The analysis on raw BMI data showed that both groups had significant reduction of BMI over time (p ≤ 0.05); however, reduction was greater in the GJ-15-mm group from 18 months onwards (p ≤ 0.05). The only complication observed was a case (1.56%) of stenosis in the group GJ-15 mm. CONCLUSION: The global analysis of BMI reduction indicated that the narrower GJ used (GJ-15-mm group) represented a favoring factor decreasing significantly more the BMI when compared to the wider one (GJ-45-mm group).

IMPROVEMENT IN OXIDATIVE STRESS AFTER DUODENOJEJUNOSTOMY IN AN EXPERIMENTAL MODEL OF TYPE 2 DIABETES MELLITUS.

Background: Type 2 Diabetes Mellitus is a multifactorial syndrome with severe complications. Oxidative stress is accepted as a causal factor of chronic complications. Aim: To demonstrate alterations in oxidative stress after metabolic surgery. Methods: Twenty-four 2-day-old Wistar rats were used. In 16, Type 2 Diabetes Mellitus was induced by 100 mg/kg streptozotocin injection. The development of diabetes was confirmed after 10 weeks using an oral glucose tolerance test. Eight diabetic rats composed the diabetic surgical group; the remaining eight composed the diabetic group. Eight animals in which diabetes was not induced formed the clinical control group. The Marchesini technique was used in the diabetic surgical group. After 90 days, the rats were sacrificed, and the oxidative stress markers were measured. Results: Thiobarbituric acid reactive substances, superoxide dismutase and catalase were significantly reduced in the diabetic surgical group compared to the diabetic group. Conclusion: The duodenojejunostomy was effective in controlling the exacerbated oxidative stress present in diabetic rats.

Racional: Diabete melito tipo 2 é síndrome multifatorial com complicações graves. O estresse oxidativo é aceito como um fator causal de complicações crônicas. Objetivo: Demonstrar alterações no estresse oxidativo após a cirurgia metabólica. Métodos: Foram utilizados 24 ratos Wistar de dois dias de idade. Em 16, diabete melito tipo 2 foi induzida por 100 mg/kg de injeção de estreptozotocina. O desenvolvimento do diabete foi confirmado após 10 semanas, utilizando teste oral de tolerância à glucose. Oito ratos diabéticos compuseram o grupo cirúrgico diabético; os oito restantes constituíram o grupo diabético. Oito animais em que não foi induzido o diabete formaram o grupo controle clínico. A técnica de Marchesini foi utilizada no grupo cirúrgico diabético. Após 90 dias, os ratos foram sacrificados, e os marcadores de estresse oxidativo foram medidos. Resultados: Ácido tiobarbitúrico, superóxido dismutase e catalase foram significativamente reduzidos no grupo cirúrgico diabético quando comparado ao grupo diabético. Conclusão: O duodenojejunostomia foi eficaz no controle do estresse oxidativo exacerbado presente em ratos diabéticos.

IMPROVEMENT IN OXIDATIVE STRESS AFTER DUODENOJEJUNOSTOMY IN AN EXPERIMENTAL MODEL OF TYPE 2 DIABETES MELLITUS / MELHORA DO ESTRESSE OXIDATIVO APÓS DUODENOJEJUNOSTOMIA EM UM MODELO EXPERIMENTAL DE DIABETE MELITO TIPO 2

ABSTRACT Background: Type 2 Diabetes Mellitus is a multifactorial syndrome with severe complications. Oxidative stress is accepted as a causal factor of chronic complications Aim: To demonstrate alterations in oxidative stress after metabolic surgery. Methods: Twenty-four 2-day-old Wistar rats were used. In 16, Type 2 Diabetes Mellitus was induced by 100 mg/kg streptozotocin injection. The development of diabetes was confirmed after 10 weeks using an oral glucose tolerance test. Eight diabetic rats composed the diabetic surgical group; the remaining eight composed the diabetic group. Eight animals in which diabetes was not induced formed the clinical control group. The Marchesini technique was used in the diabetic surgical group. After 90 days, the rats were sacrificed, and the oxidative stress markers were measured. Results: Thiobarbituric acid reactive substances, superoxide dismutase and catalase were significantly reduced in the diabetic surgical group compared to the diabetic group. Conclusion: The duodenojejunostomy was effective in controlling the exacerbated oxidative stress present in diabetic rats.

RESUMO Racional: Diabete melito tipo 2 é síndrome multifatorial com complicações graves. O estresse oxidativo é aceito como um fator causal de complicações crônicas. Objetivo: Demonstrar alterações no estresse oxidativo após a cirurgia metabólica. Métodos: Foram utilizados 24 ratos Wistar de dois dias de idade. Em 16, diabete melito tipo 2 foi induzida por 100 mg/kg de injeção de estreptozotocina. O desenvolvimento do diabete foi confirmado após 10 semanas, utilizando teste oral de tolerância à glucose. Oito ratos diabéticos compuseram o grupo cirúrgico diabético; os oito restantes constituíram o grupo diabético. Oito animais em que não foi induzido o diabete formaram o grupo controle clínico. A técnica de Marchesini foi utilizada no grupo cirúrgico diabético. Após 90 dias, os ratos foram sacrificados, e os marcadores de estresse oxidativo foram medidos. Resultados: Ácido tiobarbitúrico, superóxido dismutase e catalase foram significativamente reduzidos no grupo cirúrgico diabético quando comparado ao grupo diabético. Conclusão: O duodenojejunostomia foi eficaz no controle do estresse oxidativo exacerbado presente em ratos diabéticos.

Efeitos da cirurgia metabólica no portador de diabetes mellitus tipo 2 / Effects of metabolic surgery in diabetes mellitus type 2 patients

JUSTIFICATIVA E OBJETIVOS: O diabetes mellitus tipo 2) é a principal causa de doença renal terminal. O tratamento inicial da progressão da nefropatia diabética engloba o controle estrito da hiperglicemia, hiperfiltração e hipertensão. Algumas cirurgias envolvendo derivações intestinais melhoram a homeostase da glicose.Os objetivos deste estudo são avaliar os efeitos da cirurgia metabólica em pacientes com diabetes mellitus tipo 2. MÉTODOS:Estudo retrospectivo. Foram revisados prontuários de 17 pacientes diabéticos que foram submetidos à cirurgia de derivação do intestino proximal. Para comparar as variáveis foram utilizados os testes t de Student e Wilcoxon. Um valor de p<0,05 foi considerado estatisticamente significativo. RESULTADOS:A média da idade dos pacientes foi de 52,1 ± 3,5 anos e houve predomínio do sexo masculino (59%). Ocorreu redução estatisticamente significativa no peso, índice de massa corpórea, colesterol total, glicemia de jejum e hemoglobina glicada (p<0,05). Entretanto, não houve diferença estatisticamente significativa nos níveis de colesterol-HDL, colesterol-LDL, triglicerídeos, creatinina,depuração de creatinina, microalbuminúria e proteinúria de 24h (p>0,05). CONCLUSÃO: Os presentes dados sugerem que a cirurgia de derivação do intestino proximal, além da perda de peso, favorece o controle do diabetes mellitus tipo 2. Estudos com maior seguimento e número de pacientes são necessários para melhor definição do papel da cirurgia metabólica no tratamento do diabetes.

BACKGROUND AND OBJECTIVES: Type 2 diabetes mellitus is the leading cause of end-stage renal disease worldwide. Initial treatment in the progression of diabetic nephropathy includes strict control of hyperglycemia, hyperfiltration and arterial hypertension. Certain operations involving intestinal diversions improve glucose homeostasis. The objective of this study is to evaluate the effects of metabolic surgery in diabetes mellitus type 2 patients. METHODS: This is a retrospective study. We reviewed medical records of 17 diabetic patients who had undergone laparoscopic duodenal-jejunal exclusion. To compare the variables Student t and Wilcoxon tests were used. A p value < 0.05 was considered statistically significant. RESULTS: Patients mean age was 52.1 ± 3.5 years and 59% of them were male. There was a statistical significant decrease in weight, body mass index, total cholesterol, fasting glucose and glycosylated hemoglobin (p< 0.05). However, there was no statistical significant difference in levels of HDL-cholesterol, LDL-cholesterol, triglycerides, creatinine, creatinine clearance, microalbuminuria and proteinuria (p > 0.05). CONCLUSION: Our data suggest that laparoscopic duodenal-jejunal exclusion, in addition to weight loss, favors glycemic control in type 2 diabetes. Studies with longer follow-up and a larger number of patients are necessary to better define the role of metabolic surgery in the treatment of diabetes.

Effects of bariatric surgery on the central nervous system and eating behavior in humans: a systematic review on the neuroimaging studies / Efeitos da cirurgia bariátrica no sistema nervoso central e comportamento alimentar em humanos: uma revisão sistemática dos estudos de neuroimagem

INTRODUCTION: Neuroimaging studies suggest that obese people might show hyperactivity of brain areas regarding reward processing, and hypoactivity of brain areas concerning cognitive control, when exposed to food cues. Although the effects of bariatric surgery on the central nervous system and eating behavior are well known, few studies have used neuroimage techniques with the aim of investigating the central effects of bariatric surgery in humans. OBJECTIVES: This paper systematically and critically reviews studies using functional neuroimaging to investigate changes on the patterns of activation of central areas related to the regulation of eating behavior after bariatric surgery. METHOD: A search on the databases Medline, Web of Science, Lilacs and Science Direct on Line, was conducted in February 2013, using the keywords "Neuroimaging", "Positron-Emission Tomography", "Magnetic Resonance Imaging", "Gastric Bypass", "Gastroplasty", "Jejunoileal Bypass", "Bariatric Surgery". RESULTS: Seven manuscripts were included; the great majority studied the central effects of Roux en Y gastric bypass, using positron emission tomography or functional magnetic resonance. CONCLUSIONS: Bariatric surgery might normalize the activity of central areas concerned with reward and incentive salience processing, as the nucleus accumbens and mesencephalic tegmental ventral area, as well as circuitries processing behavioral inhibition, as the dorsolateral prefrontal cortex.

INTRODUÇÃO: Estudos de neuroimagem sugerem que indivíduos obesos podem apresentar hiperatividade de áreas cerebrais associadas à recompensa e hipoatividade em áreas associadas ao controle cognitivo quando expostos a pistas alimentares. Apesar do conhecimento dos efeitos da cirurgia bariátrica sobre o sistema nervoso central e sobre o comportamento alimentar, poucos estudos empregaram técnicas de neuroimagem para estudar os efeitos centrais da cirurgia bariátrica em humanos. OBJETIVOS: O presente trabalho revisa sistemática e criticamente os estudos de neuroimagem funcional a respeito das alterações na ativação de regiões centrais relacionadas à regulação do comportamento alimentar após a cirurgia bariátrica. MÉTODO: Foi realizada uma busca nas bases de dados Medline, Web of Science, Lilacs e Science Direct on Line, em fevereiro de 2013, utilizando-se as palavras-chave "Neuroimaging", "Positron-Emission Tomography", "Magnetic Resonance Imaging", "Gastric Bypass", "Gastroplasty", "Jejunoileal Bypass", "Bariatric Surgery". RESULTADOS: Foram incluídos sete trabalhos, dos quais a grande maioria estudou os efeitos centrais do bypass gástrico em Y de Roux empregando tomografia por emissão de pósitrons ou ressonância magnética funcional. CONCLUSÕES: A cirurgia bariátrica parece regular a atividade de áreas centrais associadas ao processamento da recompensa e da saliência de incentivo diante de pistas alimentares, como o núcleo accumbens e a área tegmental ventral do mesencéfalo, e também de circuitos neurais que processam a inibição comportamental, como o córtex pré-frontal dorsolateral.