Radiomic-based nonlinear supervised learning classifiers on non-contrast CT to predict functional prognosis in patients with spontaneous intracerebral hematoma.

PURPOSE: To evaluate if nonlinear supervised learning classifiers based on non-contrast CT can predict functional prognosis at discharge in patients with spontaneous intracerebral hematoma. METHODS: Retrospective, single-center, observational analysis of patients with a diagnosis of spontaneous intracerebral hematoma confirmed by non-contrast CT between January 2016 and April 2018. Patients with HIE > 18 years and with TCCSC performed within the first 24 h of symptom onset were included. Patients with secondary spontaneous intracerebral hematoma and in whom radiomic variables were not available were excluded. Clinical, demographic and admission variables were collected. Patients were classified according to the Modified Rankin Scale (mRS) at discharge into good (mRS 0-2) and poor prognosis (mRS 3-6). After manual segmentation of each spontaneous intracerebral hematoma, the radiomics variables were obtained. The sample was divided into a training and testing cohort and a validation cohort (70-30% respectively). Different methods of variable selection and dimensionality reduction were used, and different algorithms were used for model construction. Stratified 10-fold cross-validation were performed on the training and testing cohort and the mean area under the curve (AUC) were calculated. Once the models were trained, the sensitivity of each was calculated to predict functional prognosis at discharge in the validation cohort. RESULTS: 105 patients with spontaneous intracerebral hematoma were analyzed. 105 radiomic variables were evaluated for each patient. P-SVM, KNN-E and RF-10 algorithms, in combination with the ANOVA variable selection method, were the best performing classifiers in the training and testing cohort (AUC 0.798, 0.752 and 0.742 respectively). The predictions of these models, in the validation cohort, had a sensitivity of 0.897 (0.778-1;95%CI), with a false-negative rate of 0% for predicting poor functional prognosis at discharge. CONCLUSION: The use of radiomics-based nonlinear supervised learning classifiers are a promising diagnostic tool for predicting functional outcome at discharge in HIE patients, with a low false negative rate, although larger and balanced samples are still needed to develop and improve their performance.

Optimizing the Definition of Ischemic Core in CT Perfusion: Influence of Infarct Growth and Tissue-Specific Thresholds.

BACKGROUND AND PURPOSE: CTP allows estimating ischemic core in patients with acute stroke. However, these estimations have limited accuracy compared with MR imaging. We studied the effect of applying WM- and GM-specific thresholds and analyzed the infarct growth from baseline imaging to reperfusion. MATERIALS AND METHODS: This was a single-center cohort of consecutive patients (n = 113) with witnessed strokes due to proximal carotid territory occlusions with baseline CT perfusion, complete reperfusion, and follow-up DWI. We segmented GM and WM, coregistered CTP with DWI, and compared the accuracy of the different predictions for each voxel on DWI through receiver operating characteristic analysis. We assessed the yield of different relative CBF thresholds to predict the final infarct volume and an estimated infarct growth-corrected volume (subtracting the infarct growth from baseline imaging to complete reperfusion) for a single relative CBF threshold and GM- and WM-specific thresholds. RESULTS: The fixed threshold underestimated lesions in GM and overestimated them in WM. Double GM- and WM-specific thresholds of relative CBF were superior to fixed thresholds in predicting infarcted voxels. The closest estimations of the infarct on DWI were based on a relative CBF of 25% for a single threshold, 35% for GM, and 20% for WM, and they decreased when correcting for infarct growth: 20% for a single threshold, 25% for GM, and 15% for WM. The combination of 25% for GM and 15% for WM yielded the best prediction. CONCLUSIONS: GM- and WM-specific thresholds result in different estimations of ischemic core in CTP and increase the global accuracy. More restrictive thresholds better estimate the actual extent of the infarcted tissue.

Dyslipidemias and stroke prevention: Recommendations of the Study Group of Cerebrovascular Diseases of the Spanish Society of Neurology.

OBJECTIVE: We present an update of the Spanish Society of Neurology's recommendations for prevention of both primary and secondary stroke in patients with dyslipidaemia. DEVELOPMENT: We performed a systematic review to evaluate the main aspects of the management of dyslipidaemias in primary and secondary stroke prevention and establish a series of recommendations. CONCLUSIONS: In primary prevention, the patient's vascular risk should be determined in order to define target values for low-density lipoprotein cholesterol. In secondary prevention after an atherothrombotic stroke, a target value <55 mg/dL is recommended; in non-atherothombotic ischaemic strokes, given the unclear relationship with dyslipidaemia, target value should be established according to the vascular risk group of each patient. In both primary and secondary prevention, statins are the drugs of first choice, and ezetimibe and/or PCSK9 inhibitors may be added in patients not achieving the target value.

Recommendations of the Spanish Society of Neurology for the prevention of stroke. Interventions on lifestyle and air pollution.

OBJECTIVE: To update the recommendations of the Spanish Society of Neurology regarding lifestyle interventions for stroke prevention. DEVELOPMENT: We reviewed the most recent studies related to lifestyle and stroke risk, including randomised clinical trials, population studies, and meta-analyses. The risk of stroke associated with such lifestyle habits as smoking, alcohol consumption, stress, diet, obesity, and sedentary lifestyles was analysed, and the potential benefits for stroke prevention of modifying these habits were reviewed. We also reviewed stroke risk associated with exposure to air pollution. Based on the results obtained, we drafted recommendations addressing each of the lifestyle habits analysed. CONCLUSIONS: Lifestyle modification constitutes a cornerstone in the primary and secondary prevention of stroke. Abstinence or cessation of smoking, cessation of excessive alcohol consumption, avoidance of exposure to chronic stress, avoidance of overweight or obesity, a Mediterranean diet supplemented with olive oil and nuts, and regular exercise are essential measures in reducing the risk of stroke. We also recommend implementing policies to reduce air pollution.

Stroke prevention in patients with arterial hypertension: Recommendations of the Spanish Society of Neurology's Stroke Study Group.

OBJECTIVE: To update the recommendations of the Spanish Society of Neurology on primary and secondary stroke prevention in patients with arterial hypertension. DEVELOPMENT: We proposed several questions to identify practical issues for the management of blood pressure (BP) in stroke prevention, analysing the objectives of blood pressure control, which drugs are most appropriate in primary prevention, when antihypertensive treatment should be started after a stroke, what levels we should aim to achieve, and which drugs are most appropriate in secondary stroke prevention. We conducted a systematic review of the PubMed database and analysed the main clinical trials to address these questions and establish a series of recommendations. CONCLUSIONS: In primary stroke prevention, antihypertensive treatment should be started in patients with BP levels >  140/90 mmHg, with a target BP of < 130/80 mmHg. In secondary stroke prevention, we recommend starting antihypertensive treatment after the acute phase (first 24 hours), with a target BP of < 130/80 mmHg. The use of angiotensin-II receptor antagonists or diuretics alone or in combination with angiotensin-converting enzyme inhibitors is preferable.

Synthetic MRI in subarachnoid haemorrhage.

AIM: To evaluate the reliability of synthetic magnetic resonance imaging (SyMRI) for detecting complications associated with subarachnoid haemorrhage (SAH), such as ischaemic lesions, hydrocephalus, or bleeding complications. MATERIALS AND METHODS: Twenty patients with SAH, who underwent a conventional brain MRI and a SyMRI on a 3 T MRI machine. Comparable conventional and synthetic T2-weighted fluid attenuated inversion recovery (FLAIR) images were acquired. The presence of ischaemic lesions, hydrocephalus, extra-axial blood collections as well as the volumes of grey matter (GMv), white matter (WMv), and cerebrospinal (CSFv) were compared. The acquisition times of both sequences was also analysed. RESULTS: The concordance between the two techniques was excellent for the detection of ischaemic lesions and extra-axial collections (kappa = 0.80 and 0.88 respectively) and good for the detection of hydrocephalus (kappa = 0.69). No significant differences were detected in the number of ischaemic lesions (p=0.31) or in the Evans index (p=0.11). The WMv and CSFv measures were also similar (p=0.18 and p=0.94, respectively), as well as the volume of ischaemic lesions (p=0.79). Compared to conventional MRI, the SyMRI acquisition time was shorter regardless of the number of sections (32% and 6% time reduction for 4 or 3 mm section thickness, respectively). CONCLUSIONS: SyMRI allows the detection of potential complications of SAH in a similar way to conventional MRI with a shorter acquisition time.

Stroke units could be a valid alternative to intensive care units for patients with low-grade aneurysmal subarachnoid haemorrhage.

BACKGROUND AND PURPOSE: According to current guidelines, patients with aneurysmal subarachnoid haemorrhage (aSAH) are mostly managed in intensive care units (ICUs) regardless of baseline severity. We aimed to assess the prognostic and economic implications of initial admission of patients with low-grade aSAH into a stroke unit (SU) compared to initial ICU admission. METHODS: We reviewed prospectively registered data from consecutive aSAH patients with a World Federation of Neurosurgery Societies grade <3, admitted to our Comprehensive Stroke Centre between April 2013 and September 2018. Clinical and radiological baseline traits, in-hospital complications, length of stay (LOS) and poor outcome at 90 days (modified Rankin Scale score > 2) were compared between the ICU and SU groups in the whole population and in a propensity-score-matched cohort. RESULTS: Of 131 patients, 74 (56%) were initially admitted to the ICU and 57 (44%) to the SU. In-hospital complication rates were similar in the ICU and SU groups and included rebleeding (10% vs. 7%; P = 0.757), angiographic vasospasm (61% vs. 60%; P = 0.893), delayed cerebral ischaemia (12% vs. 12%; P = 0.984), pneumonia (6% vs. 4%; P = 0.697) and death (10% vs. 5%; P = 0.512). LOS did not differ between groups (median [interquartile range] 22 [16-30] vs. 19 [14-26] days; P = 0.160). In adjusted multivariate models, the location of initial admission was not associated with long-term poor outcome either in the whole population (odds ratio [OR] 1.16, 95% confidence interval [CI] 0.32-4.19; P = 0.825) or in the matched cohort (OR 0.98, 95% CI 0.24-4.06; P = 0.974). CONCLUSIONS: A dedicated SU, with care from a multidisciplinary team, might be an optimal alternative to ICU for initial admission of patients with low-risk aSAH.

Stroke prevention in patients with type 2 diabetes or prediabetes. Recommendations from the Cerebrovascular Diseases Study Group, Spanish Society of Neurology. / Prevención de ictus en pacientes con diabetes mellitus tipo 2 o prediabetes. Recomendaciones del Grupo de Estudio de Enfermedades Cerebrovasculares de la Sociedad Española de Neurología.

OBJECTIVE: To update the Spanish Society of Neurology's guidelines for stroke prevention in patients with type 2 diabetes or prediabetes, analysing the available evidence on the effect of metabolic control and the potential benefit of antidiabetic drugs with known vascular benefits in addition to conventional antidiabetic treatments in stroke prevention. DEVELOPMENT: PICO-type questions (Patient, Intervention, Comparison, Outcome) were developed to identify practical issues in the management of stroke patients and to establish specific recommendations for each of them. Subsequently, we conducted systematic reviews of the PubMed database and selected those randomised clinical trials evaluating stroke as an independent variable (primary or secondary). Finally, for each of the PICO questions we developed a meta-analysis to support the final recommendations. CONCLUSIONS: While there is no evidence that metabolic control reduces the risk of stroke, some families of antidiabetic drugs with vascular benefits have been shown to reduce these effects when added to conventional treatments, both in the field of primary prevention in patients presenting type 2 diabetes and high vascular risk or established atherosclerosis (GLP-1 agonists) and in secondary stroke prevention in patients with type 2 diabetes or prediabetes (pioglitazone).

Dyslipidemias and stroke prevention: recommendations of the Study Group of Cerebrovascular Diseases of the Spanish Society of Neurology. / Dislipidemias y prevención del ictus: recomendaciones del Grupo de Estudio de Enfermedades Cerebrovasculares de la Sociedad Española de Neurología.

OBJECTIVE: We present an update of the Spanish Society of Neurology's recommendations for prevention of both primary and secondary stroke in patients with dyslipidaemia. DEVELOPMENT: We performed a systematic review to evaluate the main aspects of the management of dyslipidaemias in primary and secondary stroke prevention and establish a series of recommendations. CONCLUSIONS: In primary prevention, the patient's vascular risk should be determined in order to define target values for low-density lipoprotein cholesterol. In secondary prevention after an atherothrombotic stroke, a target value <55mg/dL is recommended; in non-atherothombotic ischaemic strokes, given the unclear relationship with dyslipidaemia, target value should be established according to the vascular risk group of each patient. In both primary and secondary prevention, statins are the drugs of first choice, and ezetimibe and/or PCSK9 inhibitors may be added in patients not achieving the target value.

[Focal epileptic seizures mimicking a stroke: neuroimaging and electroencephalographic correlations]. / Crisis epilépticas focales que imitan un ictus: neuroimagen y correlaciones electroencefalográficas.

TITLE: Crisis epilépticas focales que imitan un ictus: neuroimagen y correlaciones electroencefalográficas.

Efecto antagonista del flumazenil sobre el isoflurano en la emersión de la anestesia general / Antagonist effect of flumazenil on isofluran in reversion of general anesthesia

INTRODUCTION AND OBJECTIVES: Isoflurane, an inhalational general anesthetic widely used in medical practice, belonging to the group of volatile liquids together with desflurane and sevoflurane, with various properties including sedation, hypnosis and anesthesia of patients undergoing treatment. surgical acts. Volatile inhalational anesthetics (halogenated) as mechanism of action, has the property of increasing inhibitory synaptic transmission at postsynaptic level by potentiating ion channels regulated by ligand activated by alpha-aminobutyric acid (GABA). Flumazenil is a benzodiazepine antagonist belonging to the group of imidazobenzodiazepine. It is currently known that there is no specific drug capable of antagonizing the effects of halogenates that allow the rapid and complete recovery of general anesthesia, for this reason this work focuses its efforts on demonstrating whether flumazenil has the ability to reverse the actions of the patient. isoflurane and allow an early restoration of the level of consciousness. MATERIAL AND METHODS: The study to be performed is a clinical type of longitudinal, prospective, unicentric and double blind. The sample will be formed by patients who are going to be subjected to a balanced general anesthesia. The sample will be divided into 2 large groups: group C (control) and group F (Flumazenil). At the end of the surgery, the mixture will be administered according to the selected group in a random manner (Flumazenil 0.25 mg or 0.9% solution in a 20 cc syringe) and the time of extubation, recovery time of the level of consciousness, time of discharge UCPA and hemodynamic state (FC, TAM and SO2). RESULTS: The flumazenil group showed a significantly shorter time from injection to extubation than the placebo group (p = 0.007). Differences in terms of shorter times needed to achieve Aldrete of 9 points in the flumazenil group (P = 0.04) were observed as were shorter anesthetic arousal times represented by a Ramsey 2. Heart rate, mean arterial pressure and saturation they had similar values between the 2 groups. CONCLUSION: The study showed that a single dose of 0.25 mg of flumazenil administered at the end of the surgical act, just after completing all surgical stimulation was beneficial (P = 0.007) in the context of extubation times and shorter anesthetic arousal times.

INTRODUCCIÓN Y OBJETIVOS: El isoflurano un anestésico general inhalatorio usado ampliamente en la práctica médica, perteneciente al grupo de los líquidos volátiles junto con el desflurano y sevoflurano, con variadas propiedades entre las que se encuentran la sedación, hipnosis y anestesia de los pacientes sometidos a actos quirúrgicos. Los anestésicos inhalatorios volátiles (halogenados) como mecanismo de acción, tiene la propiedad de aumentar la transmisión sináptica inhibidora a nivel postsináptico potenciando los canales iónicos regulados por ligando activados por ácido alfa-aminobutírico (GABA). El flumazenil es un antagonista benzodiazepínico perteneciente al grupo de los imidazobenzodiazepina. Se conoce actualmente que no existe un fármaco específico capaz de antagonizar los efectos de los halogenados que permitan la recuperación rápida y completa de la anestesia general, por tal motivo este trabajo centra sus esfuerzos en demostrar si el flumazenil tiene la capacidad para revertir las acciones del isoflurane y permitir un restablecimiento temprano del nivel de conciencia. MATERIALES Y MÉTODOS: El estudio a realizar es de tipo clínico de corte longitudinal, prospectivo, unicéntrico y doble ciego. La muestra se conformará por pacientes que vayan a ser sometidos a anestesia general balanceada. Se procederá a dividir la muestra en 2 grandes grupos: grupo C (control) y grupo F (flumazenil). Al final de la cirugía se administrará la mezcla según grupo seleccionado de manera al azar (flumazenil 0,25 mg o solución 0,9% en una jeringa de 20 cc) y se valorará el tiempo de extubación, tiempo de recuperación del nivel de conciencia, tiempo de alta de la UCPA y estado hemodinámico (FC, TAM y SO2). RESULTADOS: El grupo de flumazenil presentó un tiempo desde la inyección hasta la extubación significativamente más bajo que el grupo placebo (p = 0,007). Se observaron diferencias en términos de tiempos más bajos necesario para alcanzar Aldrete de 9 puntos en el grupo flumazenil (P = 0,04) al igual que tiempos de despertar anestésico más cortos representados por un Ramsey 2. La frecuencia cardíaca, presión arterial media y la saturación tuvieron valores similares entre los 2 grupos. CONCLUSIÓN: El estudio demostró que una única dosis de 0,25 mg de flumazenil administrado al final del acto quirúrgico, justo después de culminar toda estimulación quirúrgica fue beneficiosa (P = 0,007) en el contexto de tiempos de extubación y tiempos de despertar anestésico más cortos.

Leukoaraiosis May Confound the Interpretation of CT Perfusion in Patients Treated with Mechanical Thrombectomy for Acute Ischemic Stroke.

BACKGROUND AND PURPOSE: Leukoaraiosis frequently coexists in patients with acute stroke. We studied whether leukoaraiosis could confound the interpretation of CTP findings in patients treated with mechanical thrombectomy. MATERIALS AND METHODS: We analyzed 236 patients with stroke treated with mechanical thrombectomy and studied with CTP, of whom 127 (53.8%) achieved complete reperfusion. Periventricular white matter hyperintensities on MR imaging and hypodensities on NCCT were assessed through the Fazekas score. CTP-predicted nonviable tissue was defined as relative CBF <30%, and final infarct volume was quantified in DWI. We estimated mean MTT, CBV, and CBF in the asymptomatic hemisphere. In patients achieving complete reperfusion, we assessed the accuracy of nonviable tissue to predict final infarct volume using the intraclass correlation coefficient across periventricular hyperintensity/hypodensity Fazekas scores and variable relative CBF cutoffs. RESULTS: MTT was longer (Spearman ρ = 0.279, P < .001) and CBF was lower (ρ = -0.263, P < .001) as the periventricular hyperintensity Fazekas score increased, while CBV was similar across groups (ρ = -0.043, P = .513). In the subgroup of patients achieving complete reperfusion, nonviable tissue-final infarct volume reliability was excellent in patients with periventricular hyperintensity Fazekas score grade 0 (intraclass correlation coefficient, 0.900; 95% CI, 0.805-0.950), fair in patients with periventricular hyperintensity Fazekas scores 1 (intraclass correlation coefficient, 0.569; 95% CI, 0.327-0.741) and 2 (intraclass correlation coefficient, 0.444; 95% CI, 0.165-0.657), and poor in patients with periventricular hyperintensity Fazekas score 3 (intraclass correlation coefficient, 0.310; 95% CI, -0.359-0.769). The most accurate cutoffs were relative CBF <30% for periventricular hyperintensity Fazekas score grades 0 and 1, relative CBF <25% for periventricular hyperintensity Fazekas score 2, and relative CBF <20% for periventricular hyperintensity Fazekas score 3. The reliability analysis according to periventricular hypodensity Fazekas score grades on NCCT was similar to that in follow-up MR imaging. CONCLUSIONS: In patients with stroke, the presence of leukoaraiosis confounds the interpretation of CTP despite proper adjustment of CBF thresholds.

Metformin-associated hyperlactacidaemia acidosis: Diagnosis rate in standard clinical practice and its relationship with renal failure. / Acidosis con hiperlactacidemia por metformina: frecuencia de su diagnóstico en la práctica clínica habitual y relación con la insuficiencia renal.

BACKGROUND AND OBJECTIVES: Observational study on the difference between the number of cases of acidosis with hyperlactacidaemia suspected of being caused by metformin diagnosed in standard clinical practice and the incidence of this condition according to the datasheet. The study also explored the relationship between renal function and metformin-associated hyperlactacidaemia acidosis. PATIENTS: We identified cases of acidosis between 2013 and 2014 by analysing the minimum basic data set and laboratory requests. We selected patients who presented venous lactate levels >2.7 mmol/L at the time they were treated and for whom the use of outpatient metformin was confirmed. The causal relationship with metformin was independently evaluated by several researchers. The incident cases were calculated based on the number of patients who had been dispensed a drug containing metformin during the same period in the study area. RESULTS: We identified 476 cases of acidosis. Metformin was suspected of causing the condition of acidosis with hyperlactacidaemia in 20 of these cases, which represents an incidence rate of 6.57/10,000 patients. Eighty-five percent of the cases presented acute renal failure. CONCLUSIONS: The apparent incidence of acidosis with hyperlactacidaemia in patients treated with metformin is greater than that established in the datasheet (<1/10,000). The onset of metformin-associated hyperlactacidaemia acidosis is related to acute renal impairment.

Value of Posterior circulation ASPECTS and Pons-Midbrain Index on non-contrast CT and CT Angiography Source Images in patients with basilar artery occlusion recanalized after mechanical thrombectomy. / Valor de la escala ASPECTS de circulación posterior y del índice puente-mesencéfalo en imágenes de TC sin contraste y angiografía por TC en pacientes con oclusiones de la arteria basilar recanalizados tras trombectomía mecánica.

PURPOSE: Endovascular treatment with mechanical thrombectomy devices demonstrated high recanalization rates but functional outcome did not correlate with high rates of recanalization obtained. Patient selection prior to the endovascular treatment is very important in the final outcome of the patient. The primary aim of our study was to evaluate the prognostic value of posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) and Pons-Midbrain Index (PMI) scores in patients with Basilar Artery Occlusion (BAO) treated with successful angiographic recanalization after mechanical thrombectomy. METHODS: Retrospective single-center study including 18 patients between 2008 and 2013 who had acute basilar artery occlusion managed with endovascular treatment within 24hours from symptoms onset and with successful angiographic recanalization. The patients were initially classified into two groups according to clinical outcome and mortality at 90 days. For analysis we also divided patients into groups based on pc-ASPECTS (≥8vs.<8) and PMI (≥3vs.<3) on non-contrast CT (NCCT) and CT Angiography Source Images (CTASI). Imaging data were correlated to clinical outcome and mortality rate. RESULTS: CTASI pc-ASPECTS, dichotomized at <8 versus≥8, was associated with a favorable outcome (RR: 2.6; 95% CI: 1.3-5.2) and a reduced risk of death (RR: 6.5: 95% CI: 7.8-23.3). All patients that survived and were functionally independent had pc-ASPECTS score≥8. None of the 5 patients with CTASI pc-ASPECTS score less than 8 survived. CONCLUSION: PC-ASPECTS on CTASI is helpful for predicting functional outcome after BAO recanalization with endovascular treatment. These results should be validated in a randomized controlled trial in order to decide whether or not to treat a patient with BAO.

Perfusion Deficits and Mismatch in Patients with Acute Lacunar Infarcts Studied with Whole-Brain CT Perfusion.

BACKGROUND AND PURPOSE: The incidence and significance of perfusion abnormalities on brain imaging in patients with lacunar infarct are controversial. We studied the diagnostic yield of CTP and the type of perfusion abnormalities in patients presenting with a lacunar syndrome and in those with MR imaging-confirmed lacunar infarcts. MATERIALS AND METHODS: A cohort of 33 patients with lacunar syndrome underwent whole-brain CTP on admission. Twenty-eight patients had an acute ischemic lesion at follow-up MR imaging; 16 were classified as lacunar infarcts. Two independent readers evaluated NCCT and CTP to compare their diagnostic yield. In patients with DWI-confirmed lacunar infarcts and visible deficits on CTP, the presence of mismatch tissue was measured by using different perfusion thresholds. RESULTS: The symptomatic acute lesion was seen on CTP in 50% of patients presenting with a lacunar syndrome compared with only 17% on NCCT, and in 62% on CTP compared with 19% on NCCT, respectively, in patients with DWI-confirmed lacunar infarcts. CTP was more sensitive in supratentorial than in infratentorial lesions. In the nonblinded analysis, a perfusion deficit was observed in 12/16 patients with DWI-confirmed lacunar infarcts. The proportion of mismatch tissue was similar in patients with lacunar infarcts or nonlacunar strokes (32% versus 36%, P = .734). CONCLUSIONS: Whole-brain CTP is superior to NCCT in identifying small ischemic lesions, including lacunar infarcts, in patients presenting with a lacunar syndrome. Perfusion deficits and mismatch are frequent in lacunar infarcts, but larger studies are warranted to elucidate the clinical significance of these CTP findings.

Dermatosis por neblina ácida: a propósito de un caso / Dermatosis be caused by exposure to acid mist: a case report

Las dermatosis laborales son patologías frecuentes en la práctica clínica y producen un problema importante en la salud de los pacientes, siendo la dermatitis de contacto ocupacional la más frecuente. A continuación presentamos el caso clínico de un trabajador de la minería expuesto en su ambiente laboral a un aerosol ácido, llamado neblina ácida, presentando una hipopigmentación post inflamatoria secundaria a la exposición a éste. Tanto el proceso diagnóstico, como la prevención de las dermatitis de contacto laboral, debe ser un proceso riguroso, ya que su pronóstico es variable, incluso cuando se logre evitar la exposición al agente causal.

Work-related dermatoses are frequent pathologies in the clinical practice and produce a major health- problem, being the occupational contact dermatitis the most frequent disease. We study the case of a mining worker exposed in his work enviroment to an acid aerosol, called acid mist, presenting a post inflammatory hypopigmentation after the exposure to this acid. The diagnosis process, as well as the prevention of occupational contact dermatitis must be rigorous, since their prognosis is variable, despite of avoiding the exposure to the causative agent.

Fístula odontogénica: revisión de la literatura a propósito de un caso / Odontogenic sinus: a case report and literature review

Las fístulas odontogénicas son canalizaciones anormales originadas a partir de procesos infecciosos de los ápices radiculares, las cuales puede adoptar distintas morfologías en piel. Se presenta el caso de hombre de 40 años, con una lesión en mejilla derecha de 2 años de evolución. El estado de las piezas dentarias, a la inspección, era deficiente. Debido a la sospecha clínica, se solicitó una ecografía de partes blandas que fue compatible con una fístula odontogénica. Estas lesiones, muchas veces son subdiagnosticadas, lo cual limita y retrasa el tratamiento adecuado.

Odontogenic cutaneous sinus are abnormal tracts originated from infectious processes of the root canal, which can show different morphologies on the skin. We present a 40 year old man, who had a lesion on his right cheek of 2 years of duration. The tooth pieces were compromised. Due to the clinical suspicion, a soft tissue ultrasound was requested which result was consistent with odontogenic cutaneous sinus. These injuries are often underdiagnosed, limiting and delaying a proper treatment.

Dermatitis de contacto alérgica secundaria a implantes ortopédicos metálicos. A propósito de un caso clínico / Contact dermatitis secondary to metallic implants

La Dermatitis de Contacto secundaria a metales tiene una alta prevalencia en Chile y el mundo, sin embargo estas reacciones han sido poco estudiadas, pese a que podrían verse hasta en un21 por ciento de personas previamente sensibilizadas. Níquel, Cobalto y Cromo son los metales mayormente implicados. La mayoría corresponde a reacciones eccematosas. Test de parche es el gold standard para el estudio de alergia a metales, no obstante, rara vez se utiliza debido principalmente al bajo índice de sospecha de estas reacciones y a la dificultad para disponer de la aleación exacta del metal utilizado. El tratamiento muchas veces consiste en retirar el implante, puesto que el cuadro se torna inmanejable. Se presenta un caso clínico altamente sospechoso de alergia a implantes metálicos, al que se le realizó el estudio completo de alergia a metales, si bien esta no se demostró. Se realiza una revisión de la literatura existente.

Contact dermatitis secondary to metals has a high prevalence in Chile and around the world. Nevertheless, these reactions have been slightly studied, even though they might be found inpreviously sensitized people, with a percentage of 21 percent. Nickel, cobalt and chromium are the most involved metals. The majority of them correspond to eczematous reactions. Patch test is the gold standard for the study of metal allergies; however, specific tests to the implant material are rarely performed, mainly because of the low index of suspicion for these reactions and the difficulty to have the exact alloy of the metal used. Treatment often consists on removing the implant, since the situation becomes unmanageable. A highly suspicious clinical case of allergy to metallic implants is presented, a complete study of allergy to metals was made, although it couldn’t be demonstrated. A review of the existing literature was conducted.

Eritema Ab Igne como dermatosis laboral: revisión de la literatura a partir un caso clínico / Erythema ab igne as a dermatosis labor: case report and literature review

El eritema ab igne es una entidad que fue descrita por primera vez por Buschke como “hitze melanosis” (melanosis inducida por calor), en piernas de personas que trabajaban frente a fuegos abiertos o estufas de carbón. Se define como lesiones cutáneas eritematosas o hiperpigmentadas en un patrón reticulado característico, secundario a la exposición crónica de bajos niveles de radiación infrarroja. A pesar que la aparición de calefacción centralha significado una dramática disminución en su incidencia, aún se describen casos de causa cultural, médica o laboral. Una de susconsecuencias más graves es la posibilidad de aparición de un carcinoma espinocelular sobre la lesión. A continuación se presenta un caso clínico de etiología laboral y se realizará una revisión de la literatura.

Erythema ab igne is an entity that was first described by Buschke as “hitze melanosis” (heat-induced melanosis), in the legs of people working in front of open fires or coal stoves. It is defined as erythematous or hyperpigmented skin lesions in a reticulated pattern. The main cause is the chronic exposure tolow levels of infrared radiation. Although the occurrence of central heating has meant a dramatic decrease in incidence, cultural, medical or occupational causes are still described. One of the most serious consequences is the possibility of develoging an squamous cell carcinoma. We present a case of occupational aetiology and a review of the literature.

Notas micológicas XI: Tritirachium oryzae, paecilomyces formosus y alcances en la sección fumigati de aspergillus con énfasis en el complejo Aspergillus viridinutans / Micological notes XI: tritirachium oryzae, paecilomyces formosus, and extent in the Section Fumigati with enfasis in thea aspergillus viridinutans complex

En estas notas micológicas, se comentan los aspectos taxonómicos, ecológicos fisiológicos y moleculares de 2 especies fúngicas filamentosas oportunistas en humanos tales como: Tritirachium oryzae y Paecilomyces formosus, poco conocidas en su distribución en Chile. Almismo tiempo se aportan datos recientes de la literatura referentes a la distribución y patología de los nuevos integrantes de de la sección Fumigati de Aspergillus, con énfasis en el complejo A. viridinutans, un grupo de especiemorfológicamente similares y generalmente oportunista en humanos y animales, las cuales no han sido biendefinidas en la últimas décadas.

In these notes, taxonomic, ecological, physiological and molecular aspects are discussed of two opportunisticfilamentous fungal species in humans, such as Tritirachium oryzae and Paecilomyces formosus, little known in its distribution in Chile. While recent literature data concerning the distribution and pathology of the newmembers of the Aspergillus section Fumigati contribute, emphasizing the complex A. viridinutans, a group ofmorphologically similar species and generally opportunistic in humans and animals did, which have not been welldefined in recent decades.