Correlación entre escalas visuales de atrofia entorrinal y temporomesial con volumetría hipocampal / Correlation between visual scales of entorhinal and temporomesial atrophy with hippocampal volumetry

Resumen Objetivo: En pacientes con enfermedad de Alzheimer (EA) se han descrito cambios neuropatológicos tempranos en la corteza entorrinal, que anteceden el compromiso temporomesial. La evaluación de la atrofia hipocampal mediante escalas visuales y volumetría son herramientas útiles en la valoración de pacientes con deterioro cognitivo. Nuestro objetivo es establecer la correlación entre la evaluación visual de la atrofia de la corteza entorrinal (ACE), la atrofia temporomesial (ATM) y el volumen hipocampal. Material y métodos: Estudio retrospectivo de corte transversal. Se incluyeron pacientes con queja cognitiva y resonancia magnética (RM) cerebral. Se utilizaron escalas visuales de ACE y ATM. Se midió el volumen hipocampal mediante el software volBrain 1.0. Resultados: Se incluyeron 48 pacientes, 31 eran mujeres (64,6%). Mediana de edad: 76,5 (RIQ: 69-83). La correlación entre las escalas visuales ACE y la ATM del lado derecho fue de 0,67 p < 0,0001) y del lado izquierdo de 0,69 (p < 0,0001). Encontramos correlación negativa moderada entre la ACE y el volumen hipocampal, del lado derecho fue de –0,59 (p < 0,0001) y del lado izquierdo de –0,42 (p = 0,003). Conclusión: La escala de ACE muestra moderada correlación con la escala de ATM y con el volumen hipocampal. Su uso podría aportar información valiosa para valoración de trastornos cognitivos.

Abstract Objective: In patients with Alzheimer’s disease (AD), early neuropathological changes in the entorhinal cortex have been described, which precede temporomesial involvement. The evaluation of hippocampal atrophy using visual scales and volumetry are useful tools in the assessment of patients with cognitive impairment. Our objective is to establish the correlation between the visual evaluations of entorhinal cortex atrophy (ECA), temporomesial atrophy (TMA), and hippocampal volume. Material and methods: Retrospective cross-sectional study. Patients with cognitive complaint and brain magnetic resonance imaging (MRI) were included. ACE and TMA visual scales were used. Hippocampal volume was measured using the volBrain 1.0 software. Results: Forty-eight patients were included, 31 were women (64.6%). Median age was 76.5 (IQR: 69-83). The correlation between ECA and TMA on the right side was 0.67 (p < 0.0001) and on the left side was 0.69 (p < 0.0001). We found a negative moderate correlation between ECA and hippocampal volume, on the right side it was –0.59 (p < 0.0001) and on the left side it was –0.42 (p = 0.003). Conclusion: The ECA scale shows high correlation with the TMA scale and moderate correlation with hippocampal volume. Its use could provide valuable information for the assessment of cognitive disorders.

Understanding progressive multifocal leukoencephalopathy: links between milky-way appearance and mismatch T2/FLAIR.

BACKGROUND: Magnetic resonance imaging is essential to diagnose progressive multifocal leukoencephalopathy. The broad radiological spectrum may partially be explained by genetic viral mutations and their differential neurotropism. Recent pharmacovigilance-magnetic resonance imaging studies have provided new insight into pathophysiology and radiological markers of early stages. However, how lesions evolve and why certain anatomical locations are more frequently affected remains unknown. We aim to describe a new sign - T2/fluid-attenutated inversion recovery mismatch - as a complementary marker of cavitated lesions and propose a link with the milky-way appearance, a key early sign. Furthermore, we hypothesise viral dissemination routes. METHODS: We conducted a retrospective longitudinal study from January 2010 to January 2020, to analyse clinical and magnetic resonance imaging features of 13 progressive multifocal leukoencephalopathy individuals at the symptomatic stage (mean age 58.3 years (SD ± 16.8) - 61.5% were women). RESULTS: The most prevalent pathology was HIV (61.5%) and motor deficit prevailed regarding other symptoms (76.9%). Frontal lobes (76.9%), middle cerebellar peduncle (61.5%), cerebellum (61.5%), and pons (53.8%) were most commonly affected, and the cortico-ponto-cerebellar pathway seemed involved in these patients. Five patients had a pure radiological pattern. Milky-way appearance was the most frequent radiological sign (58.3%). Five patients with milky-way appearance had concomitantly T2/fluid-attenuated inversion recovery mismatch (P = 0.02). This sign showed high sensitivity and specificity (100-71%, P = 0.02) to assess evolved lesions besides diffusion. CONCLUSION: The possible tract-dependent spread, as well as clinical and genetic, have implications on the MRI variability of progressive multifocal leukoencephalopathy. The milky-way appearance could reflect a transitional phase towards evolved lesions, the latter demonstrated by T2/fluid-attenuated inversion recovery mismatch. Both could be key magnetic resonance imaging signs to diagnose progressive multifocal leukoencephalopathy at the symptomatic stage.

Hereditary spastic paraplegia: An "ears of the lynx" magnetic resonance imaging sign in a patient with recessive genetic type 11.

Hereditary spastic paraplegias are an uncommon group of monogenic diseases that include 79 types of genetic disorders. The most frequent cause of recessive hereditary spastic paraplegia is a mutation in the spastic paraplegia gene type 11 followed by type 15. This group is usually associated with non-specific clinical features like cognitive decline and may precede the progressive weakness and spasticity of lower limbs. The magnetic resonance imaging hallmark of hereditary spastic paraplegia is thinning of the spinal cord. However, brain magnetic resonance imaging may provide relevant clues for specific hereditary spastic paraplegia subtypes, and thinning of the corpus callosum has been described as the most frequent abnormality in almost one-third of recessive hereditary spastic paraplegias. Moreover, a characteristic abnormality affecting the forceps minor of the corpus callosum has been recently reported as the "ears of the lynx" sign and is highly suggestive of type 11 and 15 hereditary spastic paraplegias. We report a patient who was diagnosed with hereditary spastic paraplegia type 11 by exome genetic testing, presenting the ears of the lynx sign in the first magnetic resonance imaging assessment.