42 research outputs found
Lop Ear to Conchal Microtia
BACKGROUND
The lop ear deformity is defined by a deficient helix and scapha, underdeveloped anthelix, and downfolding of the helix. The terminology used is still confusing, and the treatment is not entirely structured. The aim of this study was to provide a new systematic surgical approach of this deformity based on our center's experience.
MATERIALS AND METHODS
All patients undergoing surgical correction of lop ears between 2007 and 2019 at Great Ormond Street Hospital were included. Patients' data, surgical techniques, and postoperative complications were recorded.
RESULTS
Based on our records, we identified 3 surgical techniques for the correction of lop ears, based on the degree of deformity encountered. In a mild lop ear, correction was achieved with a modified otoplasty technique by improving the definition of the antihelix and superior crus. In a moderate deformity, additional remodeling of the lidded helix was performed (extended otoplasty), whereas for the severe lop ear, the amount of cupping and the deficient cartilage required formal reconstruction using a carved rib cartilage framework. There were a total of 109 patients and 146 lop ears: 58 mild, 27 moderate, and 61 severe lop ears.
CONCLUSION
We feel that there is a point in the spectrum of congenital ear deformity when a severe lop ear becomes a conchal microtia and recommend this approach to simplify the management of these cases. This is intended to bring greater clarity to how to deal with lop ears, based on the severity of the deformity and the surgical techniques used
Arterio-venous malformations of the ear: Description of distinct anatomical presentation and multidisciplinary management approach
Germline melanocortin-1-receptor genotype is associated with severity of cutaneous phenotype in congenital melanocytic nevi: a role for MC1R in human fetal development
Congenital melanocytic nevi (CMN) are pigmented birthmarks that affect up to 80% of the skin surface area. The increased frequency of CMN in families of severely affected individuals is suggestive of a predisposing germline genotype. We noted a high prevalence of red hair in affected families, and considered a role for MC1R in this condition. A cohort of 166 CMN subjects underwent pigmentary phenotyping, with MC1R genotyping in 113. Results were compared with a local control group of 60 unrelated children and with 300 UK children without CMN. CMN subjects had higher prevalences of red hair and a red-haired parent than local controls and had a higher rate of compound heterozygosity and homozygosity for MC1R variants. The presence of a V92M or R allele (D84E, R151C, R160W, D294H) was associated with increasing size of the CMN, implying a growth-promoting effect of these alleles. Unexpectedly, the V92M and R151C alleles were also strongly associated with birth weight in the CMN cohort, a finding confirmed in the control group. The effect of germline MC1R genotype on development and severity of CMN led us to investigate potential broader effects on growth, revealing a role for MC1R in normal fetal development.Journal of Investigative Dermatology advance online publication, 10 May 2012; doi:10.1038/jid.2012.95
Multiple congenital melanocytic nevi and neurocutaneous melanosis are caused by postzygotic mutations in codon 61 of NRAS
Congenital melanocytic nevi (CMN) can be associated with neurological abnormalities and an increased risk of melanoma. Mutations in NRAS, BRAF, and Tp53 have been described in individual CMN samples; however, their role in the pathogenesis of multiple CMN within the same subject and development of associated features has not been clear. We hypothesized that a single postzygotic mutation in NRAS could be responsible for multiple CMN in the same individual, as well as for melanocytic and nonmelanocytic central nervous system (CNS) lesions. From 15 patients, 55 samples with multiple CMN were sequenced after site-directed mutagenesis and enzymatic digestion of the wild-type allele. Oncogenic missense mutations in codon 61 of NRAS were found in affected neurological and cutaneous tissues of 12 out of 15 patients, but were absent from unaffected tissues and blood, consistent with NRAS mutation mosaicism. In 10 patients, the mutation was consistently c.181C>A, p.Q61K, and in 2 patients c.182A>G, p.Q61R. All 11 non-melanocytic and melanocytic CNS samples from 5 patients were mutation positive, despite NRAS rarely being reported as mutated in CNS tumors. Loss of heterozygosity was associated with the onset of melanoma in two cases, implying a multistep progression to malignancy. These results suggest that single postzygotic NRAS mutations are responsible for multiple CMN and associated neurological lesions in the majority of cases
