Erdheim-Chester disease: expanding the spectrum of cutaneous manifestations.

BACKGROUND: Erdheim-Chester disease (ECD) is a rare condition and there is limited information available regarding its cutaneous manifestations. OBJECTIVES: To describe the clinical and histopathological features of cutaneous involvement in ECD. METHODS: This study is a single-centre retrospective analysis of patients 18 years old and older with biopsy-proven diagnosis of ECD between 1 January 1990 and 1 April 2017. Patients from this cohort were screened for cutaneous manifestations, and BRAF c.1799T>A (p.V600E) mutational analysis was conducted in novel skin manifestations. Primary outcomes included cutaneous manifestations (morphology and topography of lesions) and BRAF mutation status in novel cutaneous findings. RESULTS: Of 71 patients with ECD, 15 patients (21%; median age 52 years) presented with cutaneous manifestations. The most common finding was the presence of xanthelasma-like lesions (n = 8). Two patients had nonfacial cutaneous xanthomas. Seven patients presented with nonxanthomatous cutaneous involvement, with the most common finding being subcutaneous nodules (n = 5). A single patient presented with granuloma annulare-like lesions. Another patient with mixed ECD and Langerhans cell histiocytosis presented with lightly scaling, pink-red macules. In three patients, the appearance of skin lesions was the first manifestation of the disease. Most patients presented with bone/extremity pain, weight loss and other constitutional symptoms at the time of diagnosis. The BRAF V600E mutation was not found in patients with panniculitis-like and granuloma annulare-like lesions. CONCLUSIONS: The most common presentation in ECD is the presence of periorbital xanthelasma-like lesions. Other presentations include nonfacial cutaneous xanthomas, panniculitis-like lesions and granuloma annulare-like lesions. Associated symptoms at presentation include bone/extremity pain and weight loss. What's already known about this topic? Erdheim-Chester disease is a rare form of non-Langerhans cell histiocytosis characterized by lipid-laden macrophage infiltration of tissue and subsequent fibrosis. Cutaneous involvement is found in approximately 25% of patients, with the majority presenting with periorbital xanthelasma-like lesions. What does this study add? We report two novel cutaneous findings: panniculitis-like lesions and granuloma annulare-like lesions. Associated bone/extremity pain and weight loss should raise suspicion for Erdheim-Chester disease.

Accuracy between virtual surgical planning and actual outcomes in orthognathic surgery by iterative closest point algorithm and color maps: A retrospective cohort study.

BACKGROUND: To evaluate the accuracy between actual outcomes and virtual surgical planning (VSP) in orthognathic surgery regarding the use of three-dimensional (3D) surface models for registration using iterative closest point (ICP) algorithm and generated color maps. MATERIAL AND METHODS: Construction of planning and postoperative 3D models in STL files format (M0 and M1, respectively) from CBCT of 25 subjects who had been submitted to bimaxillary orthognathic surgery was performed. M0 and M1 were sent to Geomagic software in semi-automatic alignment surface mesh order of M0 and M1 for registration using ICP algorithm to calculate mean deviation (MD, MD+, MD-, SD) and root mean square (RMS - 3D Error). Color maps were generated to assess qualitative congruence between M0 and M1. From deviation analysis, 3D Error was defined as accuracy measurement. To assess the reproducibility, the workflow was performed by two evaluators multiple times. t-tests were used to assess whether all means of MD, MD+, MD-, SD and 3D Error values would be ≤ - 2 mm and ≥ 2 mm. RESULTS: High intra and inter evaluators correlation were found, supporting the reproducibility of the workflow. t-tests proved that all MDs and 3D Error values were > - 2 mm and < 2 mm. CONCLUSIONS: 3D error mean was within the standards of clinical success lower than 2 mm. ICP algorithm provided a reproducible method of alignment between 3D models and generated color maps to evaluate 3D congruence but did not answer all methodological parameters regarding the assessment of accuracy in orthognathic surgery.

Comparison of the accuracy of maxillary position between conventional model surgery and virtual surgical planning.

The aim of this study was to determine whether virtual surgical planning (VSP) is an accurate method for positioning the maxilla when compared to conventional articulator model surgery (CMS), through the superimposition of computed tomography (CT) images. This retrospective study included the records of 30 adult patients submitted to bimaxillary orthognathic surgery. Two groups were created according to the treatment planning performed: CMS and VSP. The treatment planning protocol was the same for all patients. Pre- and postoperative CT images were superimposed and the linear distances between upper jaw reference points were measured. Measurements were then compared to the treatment planning, and the difference in accuracy between CMS and VSP was determined using the t-test for independent samples. The success criterion adopted was a mean linear difference of <2mm. The mean linear difference between planned and obtained movements for CMS was 1.27±1.05mm, and for VSP was 1.20±1.08mm. With CMS, 80% of overlapping reference points had a difference of <2mm, while for VSP this value was 83.6%. There was no statistically significant difference between the two techniques regarding accuracy (P>0.05).

Access and surgical approach to the isolated intranasal basal cell carcinoma.

Primary intranasal basal cell carcinoma (BCC) is a rare tumour that presents a therapeutic challenge. Here we present two cases illustrating the lateral alarotomy to gain access to an isolated BCC involving only the intranasal lining. Successful intranasal access was achieved in both cases using the alarotomy technique. We also review other methods of repair for the isolated intranasal lining defect. The presentation of intranasal BCC purely as an isolated entity without cutaneous involvement is rare, and our surgical approach via alarotomy allows optimum visibility for tumour resection.