The diagnostic accuracy of hand-held ultrasonography in evaluation of costal cartilage calcification for grafting in rhinoplasty: A cadaveric study

BACKGROUND

Autologous costal cartilage graft (ACC) is considered a gold standard in complex rhinoplasty. Costal cartilage calcification remains a problematic issue, causing not only difficulties during the harvesting, carving, and fixation procedures but also worsening the long-term outcome with resorption.

PURPOSE

This study aims to establish diagnostic accuracy of hand-held ultrasonography in not only detecting the degree and pattern of costal cartilage calcification but also assessing its ability to predict the volume of the harvestable cartilage graft.

METHODS

The study was performed on 50 fresh cadavers with an age range between 17 and 80 years (mean 53.4 ± 16.2 years). An ultrasonographic examination of the costal cartilage of 5th, 6th, and 7th ribs of both hemithoraces was performed. The presence of calcification of the cartilages and the pattern, length, width, cross-sectional area, and depth of calcification were observed and recorded. These results were compared against direct visualization and measurement via surgical dissection.

RESULTS

Hand-held ultrasonography has a sensitivity of 94% and a specificity of 96% in detecting calcification with 96% positive predictive value and 93% negative predictive value. The positive likelihood ratio was 20.81 and the negative likelihood ratio was 0.06. Overall, the modality has demonstrated the ability to determine dimensions of the costal cartilage to within millimeters. The pattern of calcification was also correctly predicted in all 300 specimens.

CONCLUSION

Hand-held ultrasonography is an affordable and accessible choice of demonstrating the presence and pattern of calcification as well as the general dimensions of the harvestable rib cartilage.

The difference in the location of the malar summit between genders in Southeast Asians with appropriate references

Background

Facial feminization surgery and malarplasty require information concerning facial features in the malar area. Such information varies as a function of sex and race. The objectives of this study aimed to quantitatively evaluate the location of malar prominence across sexes in the Southeast Asian population, and identify sex-specific differences in malar prominence using a combination of two-dimensional (2D) computed tomography (CT) and three-dimensional (3D) CT.

Methods

The location of malar prominence was evaluated in 101 Thai adults, consisting of 52 men and 49 women. This study used both 2D CT and 3D CT to achieve greater accuracy, in which 2D CT was used to measure malar distance, malar summit width, facial width, and malar summit-to-facial width ratio whereas 3D CT was used to evaluate the positional relationship between the zygomatic summit and four reference points of the zygoma.

Results

The malar summit was positioned more laterally in males (p<0.01) and was more projected in females (p=0.01). The other 2D-parameters were wider in males. The ratio between the malar summit width and facial width showed similar results for both sexes. The vertical dimension did not show any statistically significant differences; however, a higher summit position was observed in males.

Conclusion

The zygomatic summit is positioned more laterally in males and is more projected in females. However, the ratio was similar, which indicates that the male cranium is larger in size. Based on the results in this study, when facial feminization surgery or malarplasty is performed on a Southeast Asian patient, the malar bone should be reduced horizontally and moved forward for better outcomes.

Indocyanine Green Fluorescence Angiography of the Transverse Cervical Arterial Supply to Clavicle Flaps: An Anatomical Study

OBJECTIVE

To describe the anatomy of the transverse cervical artery and to prove its perfusion to the clavicle using indocyanine green fluorescence angiography as an alternative vascularized bone for head and neck reconstruction.

STUDY DESIGN

Cadaveric dissection.

SETTING

Anatomy lab.

METHODS

Twenty-two necks and shoulders from 11 fresh-frozen cadavers were dissected. The transverse cervical artery diameter, length, emerging point, and the length of clavicle segment harvested were described. Photographic and near-infrared video recordings of the bone's medial and longitudinal cut surfaces were taken prior to, during, and after indocyanine green injection.

RESULTS

The transverse cervical artery originated from the thyrocervical trunk and emerged at the level of the medial one-third of the clavicle in 22 of 22 (100%) specimens. The average length of the pedicle was 3.6 cm (range, 2.2-4.4 cm), and the mean diameter was 2.5 mm (range, 1.8-3.4 mm). The harvested bone had a mean length of 5.1 cm (range, 4.3-5.8 cm). After injecting the indocyanine green, 22 of 22 (100%) specimens showed enhancement in the periosteum, bony cortex, and medulla.

CONCLUSION

The middle third of the clavicle can be reliably harvested as a vascularized bone with its perfusion solely from the transverse cervical artery pedicle, as shown by the near-infrared fluorescence imaging. The pedicle was sizable and constant in origin.

Nerve to the Zygomaticus Major Muscle for Facial Reanimation Surgery: A Cadaveric Study for Branching Patterns and Axonal Count

Background

In facial reanimation surgery, higher donor facial nerve axonal load yields a superior outcome. Nerves supplying the zygomaticus major muscle are primary donors for the grafting procedure; however, their topography has not been studied in detail. This study identified potential donor nerves by quantifying axon loads of the zygomaticus major muscle through histological analysis of cadaveric specimens.

Materials and Methods

Forty-three hemifaces from 26 fresh human cadavers were studied. Branching patterns of nerves were classified according to their shapes. All branches of interest were sectioned and stained for an axon count. The potential donors were mapped into each tributary of nerves supplying the zygomaticus major.

Results

Branching patterns were categorized into five types: Y-type (28%), X-type (28%), H-type (19%), E-type (14%), and F-type (11%). The mean number of axons in the most superiorly and proximally located main branches was 1387.33 ± 406.59 in Y-type, 1021.42 ± 187.79 in X-type, 1222.75 ± 193.82 in H-type, 1496.17 ± 364.567 in E-type, and 1353.40 ± 256.07 in F-type (P > 0.05). A topographic relation between facial nerves supplying the zygomaticus major muscle and their mean axonal load was illustrated. The zygomatic/buccal branches were found within 5 mm from Zuker's point in 100% of X-, Y-, H-, and E-type and 75% of F-type specimens.

Conclusions

Most proximal facial nerve branches supplying the zygomaticus major, arising at the anterior border of a parotid gland, contained over 900 axons in all five branching types. The primary subbranches may be used in selected cases if donor weakness is a concern. Further, our study provides evidence that demonstrates the precision of Zuker's point.