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Segmentation tasks in medical imaging represent an exhaustive challenge for scientists since the image acquisition nature yields issues that hamper the correct reconstruction and visualization processes. Depending on the specific image modality, we have to consider limitations such as the presence of noise, vanished edges, or high intensity differences, known, in most cases, as inhomogeneities. New algorithms in segmentation are required to provide a better performance. This paper presents a new unified approach to improve traditional segmentation methods as Active Shape Models and Chan-Vese model based on level set. The approach introduces a combination of local analysis implementations with classic segmentation algorithms that incorporates local texture information given by the Hermite transform and Local Binary Patterns. The mixture of both region-based methods and local descriptors highlights relevant regions by considering extra information which is helpful to delimit structures. We performed segmentation experiments on 2D images including midbrain in Magnetic Resonance Imaging and heart's left ventricle endocardium in Computed Tomography. Quantitative evaluation was obtained with Dice coefficient and Hausdorff distance measures. Results display a substantial advantage over the original methods when we include our characterization schemes. We propose further research validation on different organ structures with promising results.

Migraine with aura may be confused with a stroke. Magnetic resonance imaging is an important tool for the differential diagnosis. Cerebral hypoperfusion has been described in classic migraine, mainly during the aura. A 47-year-old male had an unremarkable past medical history. After sneezing, he developed a left hemi hypoesthesia, bitemporal vision loss, photopsia, and some distortion in the position of letters and words. This lasted <1 h, and it was followed by a severe headache. A magnetic resonance angiography was performed during the headache. It showed a left hemispheric hypoperfusion that did not correlate with the symptoms described by the patient. It is believed that during the aura, cerebral blood flow decreases, leading to hypoxia and decreased cellular energy generation, and these metabolic alterations define the symptoms of the patient. In our case, we documented brain hypoperfusion during the headache in the ipsilateral brain hemisphere to the symptoms, which has no clinical correlation. This condition could be due to spasm in the capillary arteries, and it may persist and influence the clinical manifestations during the headache phase in migraine with aura. A state of generalized cerebral hyperperfusion has been suggested, and there may be a coexistence of both phenomena for some period. This may open a new line of research regarding the pathophysiology and vascular changes of migraine with aura.

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