Pigmented skin lesions displaying regression features: Dermoscopy and reflectance confocal microscopy criteria for diagnosis

Melanomas and nevi displaying regression features can be difficult to differentiate. To describe reflectance confocal microscopy features in benign and malignant pigmented skin lesions characterized by regression features in dermoscopy. Observational retrospective study. Inclusion criteria were presence of dermoscopic features of regression; availability of clinical, dermoscopic and RCM imaging; definite histopathologic diagnosis. The study sample comprised 217 lesions; 108 (49.8%) melanomas and 109 were benign lesions, of which 102 (47.0%) nevi and 7 (3.2%) lichen planus‐like keratosis (lplk). Patients with melanoma were significantly older than those with benign lesions (61.9 ± 15.4 vs 46.1 ± 14.8; P < 0.001) and a higher proportion of melanomas displayed dermoscopic regression structures in more than 50% of lesion surface (n = 83/108; 76.9%; P < 0.001). On RCM examination, pagetoid cells were significantly more reported in melanoma group, than in benign lesions (86.1% vs 59.6%; P < 0.001) and were more frequently widespread distributed (65.6% vs 20.0%; P < 0.001) and both dendritic and roundish (36.6% vs 15.4%; P < 0.001) in shape. Aspecific architecture at the dermo‐epidermal junction (DEJ) was more commonly seen among melanomas than benign lesions (23.1% vs 11.9%; P = 0.002) with higher presence of dendritic and both dendritic and roundish atypical cells at the DEJ (28.7% vs 18.3% and 19.4% vs 3.7%; P < 0.001, respectively). Focal pagetoid infiltration and ringed or clod patterns were more commonly seen in benign lesion. In conclusion, the correct interpretation of regressing lesions remains a challenge, assessing carefully the extent and characteristics of architectural and cytologic atypia on RCM is an additional piece of the complex puzzle of melanoma diagnosis.     

Bail-out intracranial stenting with Solitaire AB device after unsuccessful thrombectomy in acute ischemic stroke of anterior circulation

Background

Recent trials established the efficacy of mechanical stent-retriever thrombectomy for treatment of stroke patients with large vessel occlusion (LVO) in the anterior circulation. However, stent-retriever thrombectomy may not accomplish successful recanalization in all patients. The aim of this study is to report the role of bail-out permanent stenting after failure of mechanical thrombectomy.

Review of computational fluid dynamics in the assessment of nasal air flow and analysis of its limitations

Nasal breathing difficulties (NBD) are a widespread medical condition, yet decisions pertaining to the surgical treatment of chronic NBD still imply a significant degree of subjective judgement of the surgeon. The current standard objective examinations for nasal flow, e.g., rhinomanometry and acoustic rhinomanometry, do not suffice to reliably direct the surgeon on the extent of any necessary surgery. In the last two decades, several groups have therefore considered the numerical simulation of nasal airflow. Currently, these analyses take many hours of labor from the operator, and require a huge amount of computer time and the use of expensive commercial software. Most often, their results are insufficiently validated so that virtual surgery, which is the eventual application, is still absent in clinical practice. Very recently, however, attempts at considering the finest details of the flow are beginning to appear, for example unsteady turbulent simulations validated through laboratory measurements through particle image velocimetry. In this paper, we first discuss recent developments in how computational fluid dynamics (CFD) is helping surgeons improve their understanding of nasal physiology and the effect of surgical modifications on the airflow in the nasal cavity. In a second part, the procedural and modeling challenges that still prevent CFD from being routinely used in clinical practice are surveyed and critically discussed.