Contribution of muscle MRI for diagnosis of myopathy.

Inherited myopathies are a group of disease, which, although distinct from a genetic and prognostic point of view, can lead to non-specific clinical pictures due to phenotypic overlap. Acquired immuno-mediated myopathies may also pose the problem of clinically accurate etiological orientation. The assessment of fatty infiltration and pathological increase in water volume of the muscle contingent on whole-body muscle MRI is becoming increasingly important in aiding the initial diagnosis of inherited and acquired myopathies. MRI helps orientating the clinical diagnostic hypotheses thanks to the patterns of muscle involved (more or less specific according to the entities), which led to the development of decision-making algorithms proposed in the literature. The aim of this article is to specify the proper MRI protocol for the evaluation of myopathies and the basis of the interpretation and to provide a summary of the most frequently inherited and acquired myopathies described in the literature.

Persistent epiphora after endonasal ENT surgery: CT dacryography findings.

OBJECTIVES: To analyze postoperative CT dacryography features in patients with persistent epiphora after endonasal surgery. METHODS: We conducted a retrospective study of 76 patients with a history of persistent epiphora after endonasal ENT surgery who underwent CT dacryography between January 2014 and February 2020. Volume acquisition of sub-millimeter sections allowed 2D and 3D reconstructions with virtual endoscopy of the nasosinusal cavities and the lacrimal canal. RESULTS: The postsurgical appearance of the nasosinusal cavities revealed a middle meatal antrostomy in 37% of cases, less frequently an ethmoidectomy or an inferior meatal antrostomy, sometimes completed by a middle or inferior turbinectomy. In thirty-five patients (46%), the lacrimal canal was distant from the endonasal ENT procedure. Epiphora was related to mucosal hypertrophy, constricting all or part of the lacrimal canal. Thirty-three patients (43%) showed changes in the lacrimal canal at the surgical site. In the inferior meatus, the nasolacrimal orifice was sometimes involved in the inferior turbinectomy or meatotomy, but most of the time, in the middle meatus, resection of the uncinate process prior to ethmoidectomy or middle meatotomy was associated with a lesion of the contiguous lacrimal canal. CONCLUSION: As a rare cause of persistent tearing, involvement of the nasolacrimal duct at the edge of the endonasal ENT surgery highlights the importance of intraoperative localization of the nasolacrimal duct before resection of the uncinate process or the inferior turbinate, ideally predicted by preoperative CT imaging.

Physical mapping of 18S rDNA and heterochromatin in species of family Lygaeidae (Hemiptera: Heteroptera).

Analyses conducted using repetitive DNAs have contributed to better understanding the chromosome structure and evolution of several species of insects. There are few data on the organization, localization, and evolutionary behavior of repetitive DNA in the family Lygaeidae, especially in Brazilian species. To elucidate the physical mapping and evolutionary events that involve these sequences, we cytogenetically analyzed three species of Lygaeidae and found 2n (♂) = 18 (16 + XY) for Oncopeltus femoralis; 2n (♂) = 14 (12 + XY) for Ochrimnus sagax; and 2n (♂) = 12 (10 + XY) for Lygaeus peruvianus. Each species showed different quantities of heterochromatin, which also showed variation in their molecular composition by fluorochrome staining. Amplification of the 18S rDNA generated a fragment of approximately 787 bp. The alignment of the consensus sequence with sequences from other species of Heteroptera deposited in the GenBank revealed a similarity of 98% with small differences. Fluorescent in situ hybridization with the 18S rDNA fragment revealed that this ribosomal gene was located in 1 autosomal pair at different positions in the three species. No cytogenetic data are available for these Brazilian species. The basal number and the possible chromosomal changes that occurred among the different species, as well as the evolution of these DNA sequences, are discussed.