Fine-scale harbour seal usage for informed marine spatial planning.

High-resolution distribution maps can help inform conservation measures for protected species; including where any impacts of proposed commercial developments overlap the range of focal species. Around Orkney, northern Scotland, UK, the harbour seal (Phoca vitulina) population has decreased by 78% over 20 years. Concern for the declining harbour seal population has led to constraints being placed on tidal energy generation developments. For this study area, telemetry data from 54 animals tagged between 2003 and 2015 were used to produce density estimation maps. Predictive habitat models using GAM-GEEs provided robust predictions in areas where telemetry data were absent, and were combined with density estimation maps, and then scaled to population levels using August terrestrial counts between 2008 and 2015, to produce harbour seal usage maps with confidence intervals around Orkney and the North coast of Scotland. The selected habitat model showed that distance from haul out, proportion of sand in seabed sediment, and annual mean power were important predictors of space use. Fine-scale usage maps can be used in consenting and licensing of anthropogenic developments to determine local abundance. When quantifying commercial impacts through changes to species distributions, usage maps can be spatially explicitly linked to individual-based models to inform predicted movement and behaviour.

Anatomic analysis of the conchal bowl cartilage.

PURPOSE: The conchal bowl is a portion of auricular cartilage commonly used as an autologous graft for various maxillofacial procedures. Few studies have attempted to describe the anatomy of this region in detail, particularly in relation to the curvature of the conchal bowl. The present study has provided detailed information about the anatomy of the auricular cartilage in the conchal bowl region that could assist in the surgical design of graft harvesting. MATERIALS AND METHODS: A total of 35 pairs of cadaver ears without gross deformity (15 male, 20 female; aged 39 to 99 years) were dissected to completely expose the cartilage skeleton. Each cartilage was stabilized, and the conchal bowl was mapped. The starting reference point was defined as the intersection of the lateral border of the antihelix and the superiormost aspect of the inferior crux. A prefabricated grid was then used to imprint a 4 × 5 matrix of pinpoint ink spots on the surface of each cartilage, with 6-mm increments between each spot. The grid's y and x axes were then aligned with the landmarks above. Next, a MicroScribe 3-dimensional digitizer (ghost3d.com) was used to capture the 3-dimensional coordinates for each point on the ear's surface and the coordinates were transferred into an Excel spreadsheet. After digitization, a Boley gauge was used to measure the thickness of the cartilage at each premarked spot. The gathered data points and measurements were examined to describe our parameters of interest (ie, depth, thickness, and curvature). RESULTS: The average maximum conchal bowl depth was 10.5 ± 3.0 mm in the female ears and 10.7 ± 2.5 mm in the male ears. In general, the conchal bowl depth at each point did not differ significantly between the males and females. The mean cartilage thickness ranged from 0.77 to 1.79 mm (mean 1.15 ± 0.26) in the females and 0.95 to 1.45 mm (mean 1.25 ± 0.23) in the males. Both genders showed an increase in the conchal bowl depth from inferiorly to superiorly and from posteriorly to anteriorly. The cartilage thickness also increased from posteriorly to anteriorly; however, the exact shape is complex. CONCLUSIONS: A detailed understanding of the facial anatomy is important in the practice of facial surgery. The results we have presented will provide surgeons with information on the overall dimensions, thickness, and curvature of the conchal bowl that could allow more advantageous donor site selection.

The anatomic basis of lingual nerve trauma associated with inferior alveolar block injections.

PURPOSE: This study describes the anatomic variability in the position of the lingual nerve in the pterygomandibular space, the location of the inferior alveolar nerve block injection. MATERIALS AND METHODS: Simulated standard landmark-based inferior alveolar nerve blocks were administered to 44 fixed sagitally bisected cadaver heads. Measurements were made of the diameter of the nerves and distances between the needle and selected anatomic landmarks and the nerves. RESULTS: Of 44 simulated injections, 42 (95.5%) passed lateral to the lingual nerve, 7 (16%) passed within 0.1 mm of the nerve, and 2 (4.5%) penetrated the nerve. The position of the lingual nerve relative to bony landmarks within the interpterygoid fascia was highly variable. CONCLUSION: Variation in the position of the lingual nerve is an important contributor to lingual nerve trauma during inferior alveolar block injections. This factor should be an important part of preoperative informed consent.