Relevancia de la PET/TC con [18F]FDG en la detección de enfermedad localizada en el colon en pacientes estudiados por bacteriemia o endocarditis infecciosa causadas por microorganismos enteropatógenos / Relevance of [18F]FDG-PET/CT in the detection of colon pathology in patients studied by bacteriemia or infectious endocarditis caused by enteropathogenic microorganisms

Objetivo La asociación entre la endocarditis infecciosa (EI) por Streptococcus gallolyticus y las lesiones malignas del tracto gastrointestinal está bien descrita. Asumimos que otros microorganismos enteropatógenos, como el Streptococcus viridans y Enterococcus faecalis también pueden estar relacionados con la enfermedad colorrectal. Nuestro objetivo fue determinar la frecuencia de depósitos focales de la [18F]FDG en localización colorrectal, sugestivos de lesiones tumorales, y su correlación con la enfermedad de colon y recto en pacientes con infección causada por diferentes microorganismos comensales del tracto gastrointestinal. Métodos Examinamos retrospectivamente 61 pacientes con diagnóstico de bacteriemia y de EI (posible o concluyente) según los criterios de Duke y causada por microorganismos enteropatógenos, y que fueron sometidos a una PET/TC de cuerpo entero con [18F]FDG en nuestra institución. Buscamos depósitos de la [18F]FDG en localización colorrectal, así como la presencia de lesiones morfológicas. A todos los pacientes con EI se les realizó una colonoscopia completa y los resultados histológicos se clasificaron según 4 grupos: lesión maligna, lesión premaligna, lesión benigna y ausencia de lesión. Se evaluó la correlación existente entre los hallazgos de la PET/TC con [18F]FDG y el diagnóstico histopatológico y el microorganismo implicado. Resultados La PET/TC detectó 20 depósitos de [18F]FDG en localización colorrectal (32,79%-OR: 47,28), 2 de ellos en pacientes con bacteriemia (16,7%) confirmados como lesiones malignas y premalignas y 18 en el grupo con EI (36,6%), 17 de ellos correspondientes a enfermedad colorrectal: 11 lesiones malignas, 5 premalignas y una benigna. En el subgrupo con EI la colonoscopia detectó lesiones colorrectales en el 51,02% de los pacientes: 11 malignas, 8 premalignas y 6 benignas. En el subgrupo de Streptococcus spp. se detectó una mayor incidencia de depósitos de [18F]FDG en localización colorrectal (AU)

Objective Association between Streptococcus gallolyticus infective endocarditis (IE) and malignant lesions of the gastrointestinal tract is well described. We hypothesize that other enteropathogenic microorganisms, such as Streptococcus viridans and Enterococcus faecalis are also related with colorectal pathology. Our aim is to determine the frequency of focal colorectal FDG deposits, suggestive of tumoral lesions and their correlation with colorectal pathology, in patients with infection caused by different commensal microorganisms of the gastrointestinal tract. Methods We retrospectively examined 61 patients diagnosed with bacteremia (BSI) and IE (possible or definite) according to Duke's criteria, caused by enteropathogenic microorganisms, who underwent a full-body [18F]FDG-PET/CT in our institution. We looked for colorrectal FDG deposits and morphological lesions. All IE patients underwent a complete colonoscopy and the histological results were classified into four groups: malignant lesion, premalignant lesion, benign lesion and no lesion. We evaluated the correlation between the findings of the [18F]FDG-PET/CT with the histopathological diagnosis and the involved microorganism. Results PET/CT detected 20 colorectal FDG deposits (32.79%-OR: 47.28), 2 within bacteriemic patients (16.7%) confirmed as malignant and premalignant lesions and 18 in IE group (36.6%), 17 of them corresponding to colorrectal pathology: 11 malignant, 5 premalignant and 1 benign lesions. In the IE subgroup, the colonoscopy detected colorectal lesions in 51.02% of the patients: 11 malignant, 8 premalignant and 6 benign. We found a higher incidence of colorectal FDG deposits in Streptococcus spp. subgroup. Regarding the anatomopathological colonic findings there was a predominance of patients affected by S. viridans, followed by E. faecalis and S. gallolyticus (AU)

Indocyanine green-guided liposuction for patients presenting with residual nonpitting edema after lymphovenous anastomosis.

INTRODUCTION: Lymphovenous anastomoses (LVA) techniques for the treatment of lymphedema are well defined, and results restoring lymph function are reported in the literature. However, unsatisfactory results (poor-responders) are common, leading to persistent nonpitting edema. Blind liposuction eliminates fat and fibrous tissue but may result in inadvertent damage to the lymph vessel system. Indocyanine green imaging of the lymphatic system provides the potential preservation of functioning lymphatics while conducting liposuction to address the excess adipose and fibrous tissue in these patients. Our study reports the results of a prospectively conducted technique in patients with nonpitting edema after failing previous LVA. It consists of indocyanine green-guided liposuction. PATIENTS AND METHOD: Twenty poor-responders patients to LVA who presented with persistent nonpitting edema were operated with liposuction. Limb volume measurements, SPECT-CT/lymphoscintigraphy, and ICG lymphography were recorded and complemented with a satisfaction inquiry. RESULTS: The overall percentage of volume reduction was 46.2% after liposuction (p = 0.001). None of our patients reported any set back with respect to the improvements they had achieved after LVA nor new infections. Satisfaction showed a mean improvement of 5 points in a 20-point scale. SPECT-CT/lymphoscintigraphy showed further improvements in 17 cases after liposuction, such as dermal back-flow reduction, spots along the lymphatic system, or lymph nodes not described in preoperative reports, without showing significant differences when compared with overall volume reduction (p = 0.12). CONCLUSION: Controlled liposuction with ICG seems to be an effective technique for the reduction of residual non-pitting edema in poor responder patients after LVA. Overall, volume excess reduction after liposuction was 42.6%.

The effect of tissue-segmented attenuation maps on PET quantification with a special focus on large arteries. / Efecto de la segmentación por tejidos en los mapas de atenuación sobre la cuantificación PET con especial hincapié en grandes arterias.

OBJECTIVES: Accuracy on quantitative PET image analysis relies on the correct application of attenuation correction which is one of the major challenges for PET/MRI that remains to be solved. The purpose of this study is to evaluate the effect of MRI-based attenuation maps and the use of flexible coils on the quantitative accuracy of PET images with a special focus on large arteries. MATERIALS AND METHODS: PET/CT data from eight oncologic patients was used. PET data was reconstructed using attenuation maps with different level of detail emulating several approaches available on current PET/MRI scanners. PET images obtained with CT-based and MRI-based attenuation maps were compared to evaluate the quantitative biases obtained. The quantitative effect produced by flexible MRI receiver coils on the attenuation maps was also studied. RESULTS: The use of simpler attenuation maps produced increased biases between PET data reconstructed with CT-based and MRI-based attenuation maps for fat, non-fat soft-tissues and bone. Biases in lung were very high due to the large heterogeneity and inter-patient variability of the lung. The quantification on large arteries had small deviations except for the case when flexible coils were used. The TBR provided smaller biases in all cases as it cancelled out the similar deviations obtained for arteries and reference veins. CONCLUSIONS: Simplified attenuation maps used on PET/MRI significantly increase the quantitative variability of PET images especially on lungs and bones. The quantification of PET images acquired with PET/MRI scanners applied to studies of atherosclerosis has small deviations, especially when the TBR is considered.

Downstaging of bilobar hepatocellular carcinoma after radioembolization with 90Y microspheres as a bridge to liver transplantation. / Downstaging de carcinoma hepatocelular bilobar tras radioembolización con microesferas de 90Y como puente al trasplante hepático.

Hepatic radioembolization with 90Y is an increasingly widely used locoregional therapy in the treatment of hepatocellular carcinoma. Its potential benefit has recently been described as a downstaging treatment, achieving a decreased tumour burden and allowing patients to be rescued for more radical treatments, such as liver transplantation. The case is presented of a patient diagnosed with multifocal bilobar hepatocellular carcinoma, Barcelona Clinic Liver Cancer (BCLC) intermediate stage, in whom treatment with 90Y achieved a satisfactory radiological response with a very significant reduction of tumour burden, allowing rescue with liver transplantation.

[A prospective study to determine the real value of mesenteric ¹8F-FDG uptake in cancer patients. inflammatory or tumoral mesenteric paniculitis?]. / Estudio prospectivo para determinar el valor real de la captación de ¹8F-FDG mesentérica en pacientes oncológicos: ¿paniculitis mesentérica inflamatoria o tumoral?

AIM: To assess the metabolic behavior of mesenteric panniculitis (MP), possible manifestation patterns in ¹8F-FDG PET/CT imaging and to discover if it is a reliable diagnostic method to differentiate tumor disease from inflammatory condition in this context. MATERIAL AND METHODS: A total of 2,666 PET/CT scans were evaluated prospectively from April 2012 to August 2013. Thirty patients were included (37 scans) with radiological signs of MP. There were 8 women and 22 men, aged between 39 and 81 years, in the sample. According to the ¹8F-FDG uptake in the mesenteric lesions, expressed as SUVmax, patients were classified into two different groups: Group A consisted of 10 patients with increased uptake, SUVmax ≥ 2 or greater than the activity found in the surrounding healthy mesenteric tissue, and Group B (20 patients) SUVmax <2 or indistinguishable from healthy tissue. RESULTS: No signs of mesenteric tumour involvement were demonstrated during a mean follow up of 13 months (false positives) in 80% of the Group A patients (mean SUVmax 7.11). Signs of the presence of tumor were only demonstrated in two patients of Group A (SUVmax 7.57 and 9.46) with a positive predictive value of 49.79%. All Group B patients were confirmed to be free of mesenteric involvement. CONCLUSIONS: The presence of radiological signs of suggestive of MP, increase in glycidic metabolism, even intense and focal in these lesions, which may not exclude the possibility of an ongoing tumour process, would have a high likelihood of being indicative of intense inflammatory activity.

[Nuclear medicine in Spain: high technology 2013]. / Medicina nuclear en España: alta tecnología 2013.

This article details the high technology equipment in Spain obtained through a survey sent to the three main provider companies of equipment installed in Spain. The geographical distribution of high technology by Autonomous Communities and its antiquity have been analyzed.

[Utility of radioguided surgery in splenosis]. / Utilidad de la cirugía radioguiada en la esplenosis.

Splenosis is a common finding after traumatic rupture of the spleen or therapeutic splenectomy, defined as a heterotopic autotransplantation of the spleen in peritoneal cavity and surface. In splenectomized patients due to hematologic disease, splenosis can lead to disease recurrence. We present a case of splenosis in a patient with idiopathic thrombocytopenic purpura who relapsed after splenectomy. For its localization, conventional imaging and scintigraphy with (99m)Tc-denatured red cells was performed, and at least five splenic foci were observed. Given the difficult intraoperative localization of these nodules, radioguided surgery was performed, with excellent localization and removal of all known nodules and multiple peritoneal implants of millimeter size that were not previously observed. We conclude that radioguided surgery is an excellent tool for locating foci of peritoneal splenosis, which have difficult access, thus avoiding early recurrence of the disease.

[Utility of the PET/CT in vulvar cancer management]. / Utilidad de la PET/TC en el manejo del cáncer de vulva.

OBJECTIVE: To describe the clinical impact of PET/CT in the management of patients with vulvar cancer. MATERIAL AND METHODS: Retrospective analysis of 13 PET/CT studies with (18)F-FDG (6 staging and 7 suspected recurrence) corresponding to 10 patients diagnosed with vulvar cancer by biopsy, with a mean age of 64.5 years. The preoperative PET/CT study was analyzed qualitatively according to the lesion region. Surgical excision was carried out, covering all the suspected areas according to the PET/CT study. This was compared with the histopathologic analysis. RESULTS: Abnormal vulvar PET/CT uptake was found in 9 out of the 13 studies and invasion of adjacent structures in 5 of them (urethra, perineal, vagina). The inguinal-femoral lymph nodes were considered as affected in 3 studies and one pelvic lymph node was also affected. Four of the studies had extralymphatic involvement: 3 in lung and 1 in ischiorectal fossa. The PET/CT showed a 100% sensitivity for the detection of the vulvar lesion in squamous cell carcinomas and 60% in non-squamous cell ones. There was a false positive result for local invasion due to urine contamination. One of the studies with lung metastases was related to a synchronous breast tumor. All the pathological lymph node levels detected in the PET/CT study were confirmed in the histopathology study. No new lesions were identified by surgery. PET/CT changed the therapeutic management in 8/13 studies (61.5%). CONCLUSIONS: PET/CT is postulated as a useful imaging test for the management of vulvar cancer, mainly in the identification of nodal metastases. It may affect both surgical planning and clinical management. Larger series are needed to confirm our findings.

Normal blood glucose level and (18)F-FDG PET/CT.

Patient preparation for FDG PET studies is perhaps more critical and more complex than for any other commonly performed imaging procedure. We report a patient with normal blood glucose level prior to the execution of a PET study in which FDG uptake was virtually zero in internal organs and was very extense in large muscle groups. The patient recognizes ingestion several minutes before the test. Ten days later, a repeated PET scan with normal blood glucose level, showed a normal organs distribution of FDG.

Valores normales de glucemia y 18F-FDG PET/CT / Normal blood glucose level and 18F-FDG PET/CT

La preparación de un estudio de FDG PET es probablemente de las más críticas dentro de los estudios de imagen. Presentamos el caso de una paciente que presentaba valores normales de glucemia previos a un estudio con PET, en el que la captación de la FDG fue prácticamente nula en órganos internos y muy extensa en los grandes grupos musculares. La paciente reconoció posteriormente una ingesta minutos antes de la prueba. El estudio con PET fue repetido 10 días después, también en normoglucemia, obteniendo una distribución normal de la FDG(AU)

Patient preparation for FDG PET studies is perhaps more critical and more complex than for any other commonly performed imaging procedure. We report a patient with normal blood glucose level prior to the execution of a PET study in which FDG uptake was virtually zero in internal organs and was very extense in large muscle groups. The patient recognizes ingestion several minutes before the test. Ten days later, a repeated PET scan with normal blood glucose level, showed a normal organs distribution of FDG(AU)

[Usefulness of 18F-FDG PET-CT in the presurgical assessment of malignant pleural mesothelioma treated with neoadjuvant chemotherapy]. / Utilidad de la PET-TAC 18F-FDG en la valoración prequirúrgica del mesotelioma pleural maligno tras quimioterapia neoadyuvante.

Malignant pleural mesothelioma is a relatively rare, but highly aggressive, tumor, associated to exposure to asbestos, with a life expectancy between 9 and 17 months. Chest pain and dyspnea are the most frequent symptoms. The most commonly used therapy is surgery accompanied by chemotherapy. Preoperative assessment, after chemotherapy, has been done using magnetic resonance imaging and computed tomography (CT). However, these techniques cannot predict early response to therapy, because of the slow structural change of the tumor. The aim of this case report is to review and learn about the growing use of PET-CT imaging with (18)F-FDG in the preoperative staging of malignant pleural mesothelioma and its influence in selecting the most appropriate type of surgery.

Alteraciones gammagráficas en las enfermedades metabólicas óseas / Scintigraphic alterations in metabolic bone disease

La enfermedad metabólica ósea es un término genérico que involucra a una serie de enfermedades sistémicas que producen repercusión ósea alterando el equilibrio existente entre la reabsorción y la formación de hueso. Existen, según la patología, diferentes herramientas diagnósticas que suelen incluir determinaciones analíticas, estudios radiológicos y gammagrafía ósea entre otras. Hemos realizado una revisión bibliográfica de las patologías metabólicas óseas más frecuentes, describiendo la utilidad de la gammagrafía ósea en su diagnóstico, su seguimiento así como en la valoración de la respuesta al tratamiento(AU)

Metabolic bone disease is a generic term involving a group of systemic diseases that develop bone repercussion altering the existing balance between re-absorption and bone formation. According to the pathology, there are different tools we can usually use for diagnosis, such as analytic determinations, radiologic studies and bone scan, among others. We have made a bibliographical review of the most frequent metabolic bone pathologies, describing the utility of bone scintigraphy for diagnosis, follow up and assessment of treatment response(AU)