RESUMO
Paediatric grommet insertions are a common ENT procedure which is typically carried out as a daycase procedure. National guidelines exist (NICE CG60) outlining the criteria for grommet insertions. At our institution it was noted that children were experiencing long waits for their grommet surgery with 78% breaching the national 18 week RTT target by time of surgery in the preceding 6 months. 38% of children were attending for surgery with out of date audiograms and as a consequence, due to children no longer meeting the NICE criteria for grommet insertions, 8% of children were being cancelled on the day of surgery. To improve our waiting times and reduce on the day cancellations we introduced a pilot scheme of "rapid turnover" paediatric day case theatre lists. These lists were accompanied by a pre-operative consent clinic, enabling children not requiring surgery to be cancelled. The theatre lists were run by a senior ENT registrar and had two anaesthetic "pods" i.e. two anaesthetists and two ODPs. This enabled faster turnover of patients and consequently more patients could be operated on per theatre list. Following our pilot there are no longer any children on the grommet waiting list in breach of the 18 week RTT time. Furthermore, there were no on the day cancellations due to surgery not being indicated. All staff and patients involved were satisfied with the "rapid turnover" lists and subsequently the idea is to be introduced on a regular, 2 monthly basis, to keep waiting times down.
RESUMO
In recent years finite element analysis (FEA) has emerged as a useful tool for the analysis of skeletal form-function relationships. While this approach has obvious appeal for the study of fossil specimens, such material is often fragmentary with disrupted internal architecture and can contain matrix that leads to errors in accurate segmentation. Here we examine the effects of varying the detail of segmentation and material properties of teeth on the performance of a finite element model of a Macaca fascicularis cranium within a comparative functional framework. Cranial deformations were compared using strain maps to assess differences in strain contours and Procrustes size and shape analyses, from geometric morphometrics, were employed to compare large scale deformations. We show that a macaque model subjected to biting can be made solid, and teeth altered in material properties, with minimal impact on large scale modes of deformation. The models clustered tightly by bite point rather than by modeling simplification approach, and fell out as being distinct from another species. However localized fluctuations in predicted strain magnitudes were recorded with different modeling approaches, particularly over the alveolar region. This study indicates that, while any model simplification should be undertaken with care and attention to its effects, future applications of FEA to fossils with unknown internal architecture may produce reliable results with regard to general modes of deformation, even when detail of internal bone architecture cannot be reliably modeled.
