Characterization and classification of kinesthetic motor imagery levels.

Objective.Kinesthetic Motor Imagery (KMI) represents a robust brain paradigm intended for electroencephalography (EEG)-based commands in brain-computer interfaces (BCIs). However, ensuring high accuracy in multi-command execution remains challenging, with data from C3 and C4 electrodes reaching up to 92% accuracy. This paper aims to characterize and classify EEG-based KMI of multilevel muscle contraction without relying on primary motor cortex signals.Approach.A new method based on Hurst exponents is introduced to characterize EEG signals of multilevel KMI of muscle contraction from electrodes placed on the premotor, dorsolateral prefrontal, and inferior parietal cortices. EEG signals were recorded during a hand-grip task at four levels of muscle contraction (0%, 10%, 40%, and 70% of the maximal isometric voluntary contraction). The task was executed under two conditions: first, physically, to train subjects in achieving muscle contraction at each level, followed by mental imagery under the KMI paradigm for each contraction level. EMG signals were recorded in both conditions to correlate muscle contraction execution, whether correct or null accurately. Independent component analysis (ICA) maps EEG signals from the sensor to the source space for preprocessing. For characterization, three algorithms based on Hurst exponents were used: the original (HO), using partitions (HRS), and applying semivariogram (HV). Finally, seven classifiers were used: Bayes network (BN), naive Bayes (NB), support vector machine (SVM), random forest (RF), random tree (RT), multilayer perceptron (MP), and k-nearest neighbors (kNN).Main results.A combination of the three Hurst characterization algorithms produced the highest average accuracy of 96.42% from kNN, followed by MP (92.85%), SVM (92.85%), NB (91.07%), RF (91.07%), BN (91.07%), and RT (80.35%). of 96.42% for kNN.Significance.Results show the feasibility of KMI multilevel muscle contraction detection and, thus, the viability of non-binary EEG-based BCI applications without using signals from the motor cortex.

Dual-energy CT in the differentiation between adrenal adenomas and metastases: Usefulness of material density maps and monochromatic images.

OBJECTIVE: To evaluate the behavior of adrenal adenomas and metastases with dual-energy CT, analyzing the attenuation coefficient in monochromatic images at three different levels of energy (45, 70, and 140 keV) and the tissue concentrations of fat, water, and iodine in material density maps, with the aim of establishing optimal cutoffs for differentiating between these lesions and comparing our results against published evidence. MATERIALS AND METHODS: This retrospective case-control study included oncologic patients diagnosed with adrenal metastases in the 6-12 months prior to the study who were followed up in our hospital between January and June 2020. For each case (patient with metastases) included in the study, we selected a control (patient with an adrenal adenoma) with a nodule of similar size. All patients were studied with a rapid-kilovoltage-switching dual-energy CT scanner, using a biphasic acquisition protocol. We analyzed the concentration of iodine in paired water-iodine images, the concentration of fat in the paired water-fat images, and the concentration of water in the paired iodine-water and fat-water images, in both the arterial and portal phases. We also analyzed the attenuation coefficient in monochromatic images (at 55, 70, and 140 keV) in the arterial and portal phases. RESULTS: In the monochromatic images, in both the arterial and portal phases, the attenuation coefficient at all energy levels was significantly higher in the group of patients with metastases than in the group of patients with adenomas. This enabled us to calculate the optimal cutoffs for classifying lesions as adenomas or metastases, except for the arterial phase at 55 KeV, where the area under the receiver operating characteristic curve (AUC) for the estimated threshold (0.68) was not considered accurate enough to classify the lesions. For the arterial phase at 70 keV, the AUC was 0.76 (95% CI: 0.663‒0.899); the optimal cutoff (42.4 HU) yielded 92% sensitivity and 60% specificity. For the arterial phase at 140 keV, the AUC was 0.94 (95% CI: 0.894‒0.999); the optimal cutoff (18.9 HU) yielded 88% sensitivity and 94% specificity). For the portal phase at 55 keV, the AUC was 0.76 (95% CI: 0.663‒0.899); the optimal cutoff (95.4 HU) yielded 68% sensitivity and 84% specificity. For the portal phase at 70 keV, the AUC was 0.82 (95% CI: 0.757‒0.955); the optimal cutoff (58.4 HU) yielded 80% sensitivity and 84% specificity. For the portal phase at 140 keV, the AUC was 0.9 (95% CI: 0.834‒0.987); the optimal cutoff (16.35 HU) yielded 96% sensitivity and 84% specificity. In the material density maps, in the arterial phase, significant differences were found only for the iodine-water pair, where the concentration of water was higher in the group with metastases (1018.8 ±â€¯7.6 mg/cm3 vs. 998.6 ±â€¯8.0 mg/cm3 for the group with adenomas, p < 0.001). The AUC was 0.97 (95% CI: 0.893‒0.999); the optimal cutoff (1012.5 mg/cm3) yielded 88% sensitivity and 96% specificity. The iodine-water pair was also significantly higher in metastases (1019.7 ±â€¯12.1 mg/cm3 vs. 998.5 ±â€¯9.1 mg/cm3 in adenomas, p < 0.001). The AUC was 0.926 (95% CI: 0.807‒0.977); the optimal cutoff (1009.5 mg/cm3) yielded 92% sensitivity and 92% specificity. Although significant results were also observed for the fat-water pair in the portal phase, the AUC was insufficient to enable a sufficiently accurate cutoff for classifying the lesions. No significant differences were found in the fat-water maps or iodine-water maps in the arterial or portal phase or in the water-fat map in the arterial phase. CONCLUSIONS: Monochromatic images show differences between the behavior of adrenal adenomas and metastases in oncologic patients studied with intravenous-contrast-enhanced CT, where the group of metastases had higher attenuation than the group of adenomas in both the arterial and portal phases; this pattern is in line with the evidence published for adenomas. Nevertheless, to our knowledge, no other publications report cutoffs for this kind of differentiation in contrast-enhanced monochromatic images obtained in rapid-kilovoltage-switching dual-energy CT scanners, and this is the first new contribution of our study. Regarding the material density maps, our results suggest that the water-iodine pair is a good tool for differentiating between adrenal adenomas and metastases, in both the arterial and portal phases. We propose cutoffs for differentiating these lesions, although to our knowledge no cutoffs have been proposed for portal-phase contrast-enhanced images obtained with rapid-kilovoltage-switching dual-energy CT scanners.

Modified Chevrel technique for abdominal closure in critically ill patients with abdominal hypertension and limited options for closure.

Abdominal compartment syndrome is a potentially life-threatening condition seen in critically ill patients, and most often caused by acute pancreatitis, postoperative abdominal vascular thrombosis or mesenteric ischemia. A decompressive laparotomy is sometimes required, often resulting in hernias, and subsequent definitive wall closure is challenging. AIM: This study aims to describe short term results after a modified Chevrel technique for midline laparotomies in patients witch abdominal hypertension. MATERIALS AND METHODS: We performed a modified Chevrel as an abdominal closure technique in 9 patients between January 2016 and January 2022. All patients presented varying degrees of abdominal hypertension. RESULTS: Nine patients were treated with new technique (6 male and 3 female), all of whom had conditions that precluded unfolding the contralateral side as a means for closure. The reasons for this were diverse, including presence of ileostomies, intraabdominal drainages, Kher tubes or an inverted T scar from previous transplant. The use of mesh was initially dismissed in 8 of the patients (88,9%) because they required subsequent abdominal surgeries or active infection. None of the patients developed a hernia, although two died 6 months after the procedure. Only one patient developed bulging. A decrease in intrabdominal pressure was achieved in all patients. CONCLUSION: The modified Chevrel technique can be used as a closure option for midline laparotomies in cases where the entire abdominal wall cannot be used.

Relevance of subclinical right ventricular dysfunction measured by feature-tracking cardiac magnetic resonance in non-ischemic dilated cardiomyopathy.

BACKGROUND: Right ventricular (RV) dysfunction in patients with non-ischemic dilated cardiomyopathy (NICM) is associated with cardiovascular events. To analyze the feasibility of assessing RV myocardial deformation by feature tracking (FT)-cardiac magnetic resonance (CMR), and its usefulness as a prognostic marker. METHODS: Retrospective study of NICM patients undergoing CMR. Longitudinal FT-RV free wall (LFT-RVFW) and fractional area change (FAC) were obtained. Correlation with standard RV parameters was studied. An association with combined event (heart failure (HF), ICD implantation or cardiovascular death) was assessed using a logistic regression model. RESULTS: 98 patients (64 ± 13 years) were included. Left ventricular (LV) systolic function (LVEF 29.5 ± 9.6%, 47% with LVEF ≥ 30%) and RV (RVEF 52.2 ± 14.6%, 72% with RVEF ≥ 45%). Follow-up of 38 ± 17 months, 26.5% presented at least one admission for HF. An excellent correlation of LFT-RVFW (r = 0.82) and FAC (r = 0.83) with RVEF was evident. No association of RV-FT parameters with prognosis entire study population was found. However, in patients with LVEF ≥ 30%, admissions for HF were associated with lower LFT-RVFW (-21.6 ± 6.6% vs -31.3 ± 10%; p = 0.006) and FAC (36.6 ± 9.6% vs 50.5 ± 13.4%; p < 0.001) values. Similar differences were observed when only patients with RVEF ≥ 45% were considered. An LFT-RVFW cut-off point of -19.5% and FAC of 36.5% showed good prognostic performance. Decreased LFT-RVFW or FAC represented an independent predictor of combined event in patients with LVEF ≥ 30%. CONCLUSIONS: In NICM patients without severe LV dysfunction, decreased values of LFT-RVFW and/or FAC were associated with HF admissions, independently of RVEF.

Isoniazid preventive therapy completion in children under 5 years old who are contacts of tuberculosis cases in Lima, Peru: study protocol for an open-label, cluster-randomized superiority trial.

BACKGROUND: Children < 5 years old in contact with TB cases are at high risk for developing severe and fatal forms of TB. Contact investigation, BCG vaccination, and isoniazid preventive therapy (IPT) are the most effective strategies to prevent TB among children. However, the implementation of IPT faces challenges at several stages of the cascade of care of TB infection among children, particularly those less than 5 years old. In Peru, a large proportion of children do not complete IPT, which highlights the need to design effective interventions that enhance preventive therapy adherence and completion. Although the body of evidence for such interventions has grown, interventions in medium TB incidence settings are lacking. This study aims to test the effectiveness, acceptability, and feasibility of an intervention package to increase information and motivation to complete IPT among children < 5 who have been prescribed IPT. METHODS: An open-label, cluster-randomized superiority trial will be conducted in two districts in South Lima, Peru. Thirty health facilities will be randomized as clusters, 10 to the intervention and 20 to control (standard of care). We aim to recruit 10 children from different households in each cluster. Participants will be caretakers of children aged < 5 years old who initiated IPT. The intervention consists of educational material, and short message services (SMS) reminders and motivators. The primary outcomes will be the proportion of children who picked up > 90% of the 24 weeks of IPT (22 pick-ups) and the proportion of children who picked up the 24 weeks of IPT. The standard of care is a weekly pick-up with monthly check-ups in a health facility. Feasibility and acceptability of the intervention will be assessed through an interview with the caretaker. DISCUSSION: Unfavorable outcomes of TB in young children, high effectiveness of IPT, and low rates of IPT completion highlight the need to enhance adherence and completion of IPT among children < 5 years old. Testing of a context-adapted intervention is needed to improve IPT completion rates and therefore TB prevention in young children. TRIAL REGISTRATION: ClinicalTrials.gov NCT03881228. Registered on March 19, 2019.

Pharmacokinetics/pharmacodynamics and therapeutic drug monitoring of ceftazidime/avibactam administered by continuous infusion in patients with MDR Gram-negative bacterial infections.

BACKGROUND: Therapeutic drug monitoring (TDM) of ß-lactams in critically ill patients has been correlated with better clinical outcomes. Evidence on TDM of newer ß-lactams such as ceftazidime/avibactam administered by continuous infusion (CI) is very limited. OBJECTIVES: To describe our experience with TDM of ceftazidime/avibactam and pharmacokinetic/pharmacodynamic (PK/PD) target attainment in patients with MDR bacterial infections. Clinical outcomes of ceftazidime/avibactam administered by CI were also assessed. METHODS: Patients treated with ceftazidime/avibactam administered by CI and undergoing TDM of ceftazidime plasma concentrations were included. Blood samples were obtained as part of the TDM program. The PK/PD therapeutic target of ceftazidime/avibactam was defined as 100%fT > 4 × MIC of the causative pathogen, and 100%fT > 10 × MIC was considered overexposure. Dose changes were made according to the TDM results. RESULTS: Thirty-one patients were included. Ceftazidime/avibactam total daily doses ranged from 1 g/0.25 g to 6 g/1.5 g. Twenty-six patients (83.9%) achieved a 100%fT > 4 × MIC, 15 (48.4%) of which were overexposed (100%fT > 10 × MIC). Dose reduction was suggested in 16/28 (57.1%) patients and dose maintenance in 12/28 (42.9%). Overall clinical cure was observed in 21 (67.7%) patients, and 18 of these (85.7%) achieved a 100%fT > 4 × MIC. CONCLUSIONS: Administering ceftazidime/avibactam by CI enabled the desired PK/PD target to be achieved in a large proportion of patients, even at lower doses than those recommended for a 2 h extended infusion. We suggest that the use of CI with TDM may be a useful tool for reducing initial doses, which could help to reduce antimicrobial-related adverse effects and treatment costs.

Hypofractionated whole breast irradiation after IORT treatment is safe in patients receiving adjuvant chemotherapy.

INTRODUCTION: Hypofractionated whole breast irradiation (hWBI) and intraoperative radiotherapy (IORT) could be associated in breast cancer patients showing high-risk factors of local recurrence after breast conserving therapy (BSC). The aim of this trial was to evaluate, for the first time, the toxicity and cosmesis of hWBI after photon-IORT in high-risk patients treated by adjuvant chemotherapy. MATERIALS AND METHODS: Thirty-one high-risk localized breast cancer patients treated by BCS, IORT (20 Gy), and adjuvant chemotherapy were included from February 2019 to August 2020 in this prospective trial, of hWBI (40.5 Gy/2.67 Gy/15 fractions). Acute and late toxicity (CTCAEv5.0) and cosmesis (Harvard scale), were assessed after treatment. RESULTS: All patients completed their treatment and were evaluable after treatment. No patients showed severe (G3) acute/late toxicity. Excellent/good cosmesis at least 6 months after completing the treatment, was present in 93.6% of the patients. CONCLUSION: hWBI in high-risk localized breast cancer patients treated by chemotherapy seems to have similar toxicity and cosmetic results than conventionally fractionated WBI in combination to photon-IORT after BCS.

[Comprehensive post-stroke rehabilitation: its long-term effects and the socio-environmental factors conditioning access to it]. / Rehabilitación integral postictus: efectos a largo plazo y factores socioambientales condicionantes del acceso.

INTRODUCTION: Recovery of all brain functions affected after stroke is essential for the patient's quality of life, with comprehensive rehabilitation key. OBJECTIVES: Identify social and environmental factors affecting access to comprehensive post-ictus rehabilitation, and assess long-term effects of comprehensive rehabilitation on patient functionality. PATIENTS AND METHOD: 171 consecutive patients (84 women and 87 men) hospitalized in 2015 in Neurology Service with first ischemic stroke, without prior functional dependence, candidates for comprehensive rehabilitation are studied. Various socio-environmental and clinical variables potentially associated with access to it are analyzed. The long-term prognostic impact (average period of 54 months) on the functional situation is studied using the Barthel index. RESULTS: The average age of patients is 69 years. Only 53% were able to access the recommended comprehensive rehabilitation. Predictor variables of access were resulted: residence in urban environment (OR: 2,957; 95% CI: 1,067-8,199; p = 0.037), complement with private rehabilitation (OR: 2,89; 95% CI: 1,130-7,392; p = 0.027), best Rankin to high (OR: 22,437; 95% CI: 3,247-155,058; p = 0.014). After average follow-up for 54 months, of the 137 survivors, access to comprehensive post-ictus rehabilitation was independently associated with better long-term functional situation (OR: 12,441; 95% CI: 4.7-32.5; p < 0.001). CONCLUSIONS: Comprehensive post-ictus rehabilitation is associated with better long-term prognosis, but access to it is conditioned by environmental and social factors such as the place of residence and the possibility of contracting private services.

TITLE: Rehabilitación integral postictus: efectos a largo plazo y factores socioambientales condicionantes del acceso.Introducción. La recuperación de todas las funciones cerebrales afectadas tras un ictus es esencial para la calidad de vida del paciente y la rehabilitación integral resulta clave. Objetivos. Identificar los factores sociales y ambientales condicionantes del acceso a la rehabilitación integral postictus, y valorar los efectos a largo plazo de la rehabilitación integral en la funcionalidad del paciente. Pacientes y método. Se estudia a 171 pacientes consecutivos (84 mujeres y 87 hombres) hospitalizados en 2015 en el servicio de neurología con un primer ictus isquémico, sin dependencia funcional previa, candidatos a rehabilitación integral. Se analizan diversas variables socioambientales y clínicas potencialmente asociadas al acceso a ésta. Se estudia el impacto pronóstico a largo plazo (período medio de 54 meses) sobre la situación funcional mediante el índice de Barthel. Resultados. La edad media de los pacientes era de 69 años. Sólo el 53% pudo acceder a la rehabilitación integral recomendada. Resultaron variables predictoras del acceso: residencia en medio urbano ­odds ratio (OR): 2,957; intervalo de confianza al 95% (IC 95%): 1,067-8,199; p = 0,037­, complemento con rehabilitación privada (OR: 2,89; IC 95%: 1,13-7,392; p = 0,027) y mejor Rankin en el momento del alta (OR: 22,437; IC 95%: 3,247-155,058; p = 0,014). Tras un seguimiento medio durante 54 meses de los 137 supervivientes, el acceso a rehabilitación integral postictus se asoció independientemente a mejor situación funcional a largo plazo (OR: 12,441; IC 95%: 4,7-32,5; p menor de 0,001). Conclusiones. La rehabilitación integral postictus está asociada a un mejor pronóstico a largo plazo, pero su acceso está condicionado por factores ambientales y sociales, como el lugar de residencia y la posibilidad de contratar servicios privados.

Hypofractionated whole breast irradiation after IORT treatment: evaluation of acute toxicity and cosmesis.

INTRODUCTION: Hypofractionated whole breast irradiation (HWBI) is the current standard of treatment after breast conservative surgery (BCS). Intraoperative radiotherapy (IORT) must be associated to WBI in patients showing high-risk factors of local recurrence in the definitive pathology report. The aim of this trial was to evaluate, for the first time, the acute toxicity and cosmesis of HWBI after photon-IORT. MATERIALS AND METHODS: Twenty-six luminal breast cancer patients treated by BCS and IORT(20 Gy) were included between February and December 2019, in this prospective trial, of adjuvant HWBI (40.5 Gy/2.67 Gy/15 fractions). Acute toxicity (CTCAEv5.0) and cosmesis (Harvard scale), were assessed 3 months after treatment. RESULTS: All patients completed their treatment without interruptions. All cases were evaluable 3 months after treatment showing no toxicity ≥ G3 and excellent/good cosmesis assessment in 88% of the patients. CONCLUSION: HWBI seems to have similar acute toxicity and cosmesis results than conventionally fractionated WBI in combination to photon-IORT after BCS.

Left ventricular pseudothrombus: multimodality imaging rules out a "ghost image" of a thrombus seen on cardiac computed tomography. / Pseudotrombo en ventrículo izquierdo. "Imagen fantasma" en tomografía axial computarizada. Diagnóstico multimodalidad.

Cardiac computed tomography showed a hypodense area in the apex of the left ventricle in a 57-year-old man with a history of anterior myocardial infarction three years earlier. To confirm or rule out a suspected thrombus, he underwent gadolinium-enhanced cardiac magnetic resonance imaging, contrast-enhanced two-dimensional transthoracic echocardiography, and three-dimensional transthoracic echocardiography. Multimodality imaging ruled out the presence of a thrombus.

Immunohistochemical analysis of cancer-associated fibroblasts and podoplanin in head and neck cancer.

BACKGROUND: To immunohistochemically evaluate the association between the presence of cancer-associated fibroblasts (CAFs) and the tumour expression of podoplanin (PDPN) in head and neck squamous cell carcinoma (HNSCC) and their association with clinicopathological variables. MATERIAL AND METHODS: A tissue microarray (TMA) with biopsy sections from patients diagnosed with HNSCC was stained with antibodies against the CAFs marker, α-smooth muscle actin (α-SMA), and PDPN. We subsequently evaluated their expression to determine the association between them and with clinicopathological variables including age, primary tumour site, TNM stage, and tumour differentiation grade. RESULTS: Positive reaction to α-SMA was observed in the tumour stroma, revealing spindle-shaped cells compatible with CAFs, which showed a high expression in 62% of cases and a significant association with laryngeal carcinomas, advanced clinical stages, and lower tumour differentiation (P ≤ 0.05). PDPN staining on tumour cells showed low expression in 72% of cases, and it was not associated with any clinicopathological variable or with the presence of CAFs. CONCLUSIONS: The presence of CAFs in the tumour stroma is related to an aggressive phenotype and could increase as the disease progresses, although based on our findings, it would have no relationship, at least directly, with the expression of PDPN.

Influence of nanoholes array geometrical parameters on magnetic properties of Dy-Fe antidot thin films.

Nanoscale artificially engineered spintronic materials could be used to enlarge the storage density of magnetic recording media. For this purpose, magnetic nanostructures such as antidot arrays exhibiting high uniaxial magnetic anisotropy are new contestants in the field of ultrahigh density magnetic data storage devices. In this context, we focus on the synthesis of nanostructured magnetic materials consisting of Dy-Fe alloyed antidot thin films, deposited onto the surface of nanoporous alumina membranes served as patterned templates. Noticeable variations of in the in-plane magnetic anisotropy have been observed by modifying the layer thickness at both microscopic and macroscopic scales. The microscopic magnetic properties have been locally studied by Nano-MOKE magnetometry. For thinner antidot samples with 15, 20 and 25 nm in thickness, a tri-axial in-plane magnetic anisotropy has been detected. Meanwhile, for thicker antidot samples (40-60 nm of layer thickness), an in-plane uniaxial magnetic anisotropy has been noted. We attribute these changes in the magnetic anisotropy to the strong correlation between the edge-to-edge distance among adjacent nanoholes, W, and the local magnetic anisotropy of antidot samples. The effective magnetic anisotropy exhibits an unexpected crossover from the in-plane to out-of-plane direction due to the increasing of the effective perpendicular magnetic anisotropy with varying the layer thickness of antidot thin films. Therefore, we detected a critical layer thickness, t = 25 nm for the Dy-Fe alloy antidot arrays, at which the appearance of the perpendicular magnetization is observed. Furthermore, an enhancement in the Curie temperature of the antidot arrays compared to the continuous thin films has been obtained. We attribute these effects to the complex magnetization reversal processes and the high thermal stability of the hexagonal structure of antidot arrays. These findings can be of high interest for the development of novel magnetic sensors and for thermo-magnetic recording patterned media based on template-assisted deposition techniques.

Extraperitoneal laparoscopic ventral hernia repair: one step beyond.

PURPOSE: The objective of the study was to analyze the experience of the Department of Surgery of two institutions of high complexity in Colombia, with the extra peritoneal ventral hernia repair by laparoscopy during the last 2 years and characterize the clinical and surgical aspects most relevant in the procedures performed. METHODS: Observational, descriptive, retrospective study, case series type: collection of data by clinical history and analysis thereof including calculation of frequency and central tendency measurements. RESULTS: 59 Cases of Ventral Hernia Repair by laparoscopy, 41 with Transabdominal Preperitoneal approach and 18 totally Extraperitoneal. In total, 7 complications were presented as follows: 1 Case of recurrence, 1 case of chronic pain, 2 complications Dindo-Clavien IIIa and 1 complication IIIb. CONCLUSIONS: The repair of the ventral hernia by Extraperitoneal route is an innovative approach of increasing popularity, which avoids the contact of the mesh with the intestines, thus avoiding the potential complications that this situation generates with good outcomes and at a lower cost.

Biomechanical and functional effects of shoulder kinesio taping® on cerebral palsy children interacting with virtual objects.

The reaching of objects is usually practiced by CP children in conventional or Virtual Reality-based therapies to enhance motor skill performance. Recently, Kinesio Taping® method has been studied to increase mechanical stability and improve functional movement of the upper limb; however, its influence on CP children´s upper limb motion has been rarely quantified due to lack of sensory measurement. Therefore, in this paper, we evaluate the biomechanical and functional effects of applying shoulder Kinesio Taping® on CP children in the reaching-transporting of virtual objects, by using a low-cost tracking device, exact robust differentiation of data and a simple nonlinear biomechanical dynamic model of the trunk and arm.

Advanced magnetic resonance imaging techniques for tumors of the head and neck. / Técnicas avanzadas de resonancia magnética en patología tumoral de cabeza y cuello.

Magnetic resonance imaging has become a fundamental tool for the evaluation of head and neck tumors. The anatomic details that magnetic resonance images provide are fundamental for diagnosing, characterizing, and staging both primary tumors and lymph node metastases. In addition to technical improvements in anatomic sequences, such as Dixon techniques to improve fat suppression, other sequences being developed, such as diffusion and perfusion, provide molecular, biological, and physiological information about the tumor and are yielding imaging biomarkers that can help in determining the tumor's biology at the time of diagnosis and in the follow-up of the disease. Magnetic resonance imaging also provides very useful information about the response to treatment.

Juxtaoral organ: an anatomical finding to be considered.

The juxtaoral organ (JOO) is a vestigial anatomical structure which is not usuallydescribed in lectures and classic texts of general histology and oral histology, despiteit being included in the "Terminologia Histologica: International terms for humancytology and histology". Although there is evidence about its histological structure,there are no macroscopic anatomical reports about it. We report the finding ofa structure of glandular macroscopic appearance in a horizontal section of a plastinatedhuman head belonging to the Morphology Laboratory of the Department ofBiomedical Basic Sciences at the University of Talca. Due to its location, dimensionsand anatomical relations, we determined it to be the JOO. Using a digital calliper, wemeasured the anteroposterior and transverse dimensions of the JOO and observedits anatomical relationships with neighbouring structures of clinical relevance. Weconclude that the JOO is relevant to surgical practice due to its anatomical relationswith relevant structures such as inferior third molar and lingual nerve. Its clinicalapplication lies in the differential diagnosis with invasive processes of malignantneoplasia originating in the oral cavity.

[Determination and hierarchy of clinical signs for early detection of cerebrotendinous xanthomatosis]. / Determinación y jerarquización de signos clínicos para diagnóstico temprano de xantomatosis cerebrotendinosa.

BACKGROUND: Cerebrotendinous Xanthomatosis (CTX) is an autosomal recessive disease caused by mutations in the CYP27A1 gene resulting in a decreased synthesis of bile acids. An early diagnosis and treatment would reduce the longterm complications observed in this disease. AIM: To identify and hierarchize initial clinical signs of CTX to establish an early diagnostic suspicion index. MATERIAL AND METHODS: Clinical information was collected from 387 patients diagnosed with CTX, published in MEDLINE between 1968 and 2016. Clinical manifestations were identified, determining their prevalence and age of onset. Sensitivity, specificity and the positive Likelihood ratio (LR+) was calculated for each clinical sign evaluated. RESULTS: The average ages for early symptoms' onset and CTX diagnosis were 13.3 ± 10.6 years and 34.6 ± 12.6 years respectively. The early clinical signs and their respective LR+ were: juvenile cataracts (143), epilepsy (81), chronic diarrhea (15.6) and psychomotor development delay (3.4). The presence of consanguinity among parents resulted in a LR+ of 31. The combination of two early signs increased the post-test probability to 30%. If the early diagnostic criteria would have been applied in three Chilean patients with diagnosis of CTX, their disease would have been diagnosed from 12 to 25 years earlier. CONCLUSIONS: The use of a hierarchical system of predictive clinical signs allows an early screening of CTX, which may avoid the natural progression of the disease using an appropriate treatment.

Determinación y jerarquización de signos clínicos para diagnóstico temprano de xantomatosis cerebrotendinosa / Determination and hierarchy of clinical signs for early detection of cerebrotendinous xanthomatosis

Background: Cerebrotendinous Xanthomatosis (CTX) is an autosomal recessive disease caused by mutations in the CYP27A1 gene resulting in a decreased synthesis of bile acids. An early diagnosis and treatment would reduce the longterm complications observed in this disease. Aim: To identify and hierarchize initial clinical signs of CTX to establish an early diagnostic suspicion index. Material and Methods: Clinical information was collected from 387 patients diagnosed with CTX, published in MEDLINE between 1968 and 2016. Clinical manifestations were identified, determining their prevalence and age of onset. Sensitivity, specificity and the positive Likelihood ratio (LR+) was calculated for each clinical sign evaluated. Results: The average ages for early symptoms' onset and CTX diagnosis were 13.3 ± 10.6 years and 34.6 ± 12.6 years respectively. The early clinical signs and their respective LR+ were: juvenile cataracts (143), epilepsy (81), chronic diarrhea (15.6) and psychomotor development delay (3.4). The presence of consanguinity among parents resulted in a LR+ of 31. The combination of two early signs increased the post-test probability to 30%. If the early diagnostic criteria would have been applied in three Chilean patients with diagnosis of CTX, their disease would have been diagnosed from 12 to 25 years earlier. Conclusions: The use of a hierarchical system of predictive clinical signs allows an early screening of CTX, which may avoid the natural progression of the disease using an appropriate treatment.

Kinematic reconstruction in cardiovascular imaging. / Reconstrucción cinemática en imagen cardiovascular.

OBJECTIVE: Advances in clinical applications of computed tomography have been accompanied by improvements in advanced post-processing tools. In addition to multiplanar reconstructions, curved planar reconstructions, maximum intensity projections, and volumetric reconstructions, very recently kinematic reconstruction has been developed. This new technique, based on mathematical models that simulate the propagation of light beams through a volume of data, makes it possible to obtain very realistic three dimensional images. This article illustrates examples of kinematic reconstructions and compares them with classical volumetric reconstructions in patients with cardiovascular disease in a way that makes it easy to establish the differences between the two types of reconstruction. CONCLUSION: Kinematic reconstruction is a new method for representing three dimensional images that facilitates the explanation and comprehension of the findings.

Neuroradiologic correlation with aphasias. Cortico-subcortical map of language. / Correlación neurorradiológica de las afasias. Mapa cortico-subcortical del lenguaje.

Aphasia is an acquired language disorder due to a cerebral lesion; it is characterized by errors in production, denomination, or comprehension of language. Although most aphasias are mixed, from a practical point of view they are classified into different types according to their main clinical features: Broca's aphasia, Wernicke's aphasia, conduction aphasia, transcortical aphasia, and alexia with or without agraphia. We present the clinical findings for the main subtypes of aphasia, illustrating them with imaging cases, and we provide an up-to-date review of the language network with images from functional magnetic resonance imaging and tractography.