[Magnetic resonance imaging findings on the eyelids of Japanese cadavers for anatomical studies and a comparative examination of their histological pictures].

OBJECTIVE: To clarify ambiguous areas in interpreting MR images of Japanese eyelids, a histological examination was conducted on cadavers after the MRI for a comparative evaluation. SUBJECTS AND METHODS: Orbital sections including the unilateral upper and lower palpebrae of two Japanese cadavers (an 87-year-old woman and a 49-year-old man) were examined. Following MRI, the specimens of the same cadavers were examined histologically for a comparative evaluation. RESULTS: In both cadavers, a high signal intensity area with a hazy appearance unlike the orbital fat--fibroadipose tissue rich with connective tissue--was recognized between the orbicularis muscle and orbital septum. The same high signal intensity area that appeared to encase the posterior section of the descending orbital fat was also composed of fibroadipose tissue. Because of the presence of this intervening fibroadipose tissue, the posterior surface of the orbicularis muscle and the orbital septum could not come into contact with each other. CONCLUSION: Although limited to only two subjects, the current observation proved that fibroadipose tissue exists not only in the superficial layer of the orbital fat but that it further descends to surround the lowest portion of the orbital fat. As already reported, it was mainly the fibroadipose tissue, but not the orbital fat, that descends into the palpebral space.

Electrophysiological and histopathological characteristics of progressive atrioventricular block accompanied by familial dilated cardiomyopathy caused by a novel mutation of lamin A/C gene.

UNLABELLED: Conduction defect caused by lamin A/C gene mutation. INTRODUCTION: Mutations of lamin A/C gene (LMNA) cause dilated cardiomyopathy (DCM) with atrioventricular (AV) conduction defect, although the electrophysiological and histological profiles are not fully understood. METHODS AND RESULTS: We analyzed a large Japanese family (21 affected and 203 unaffected members) of DCM with AV block. The responsible LMNA mutation of IVS3-10A>G was novel and caused an aberrant splicing. The first clinical manifestation was low-grade AV block or atrial fibrillation (AF), which developed in affected members aged >or=30 years. We observed that the AV block progressed to third-degree within several years. The electrophysiological study of the four affected members revealed an impairment of intra-AV nodal conduction. Because of advanced AV block, pacemakers were implanted in 14 out of 21 affected members at the mean age of 44 years. Three affected members died suddenly and two affected members died of heart failure and/or ventricular tachycardia (VT) even after the pacemaker implantation. Postmortem examination showed conspicuous fibrofatty degeneration of the AV node. Endomyocardial biopsies showed remarkably deformed nuclei and substantial glycogen deposits in the subsarcolemma. CONCLUSION: The clinical phenotype in this family was characterized by (1) the first manifestation of the prolonged PQ interval or AF in adolescence, (2) progressive intra-AV nodal block to the third degree in several years, and (3) progressive heart failure after pacemaker implantation. Histological study revealed preferential degeneration at the AV node area and novel cellular damages in the working myocardium.