Publications by authors named "Brian C W Kot"

Debilitated stranded cetaceans with low survival likelihood, may require euthanasia to avoid further suffering. Euthanasia can involve chemical or physical methods, including ballistics. Ballistics should cause instantaneous, permanent insensibility through brainstem disruption.

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Background: Computed tomography (CT) is a non-invasive diagnostic imaging modality which can be used to study the anatomy and morphology of live or deceased animals in-situ. In cetaceans, existing CT anatomy studies mostly focused on the head and thoracic regions. Using postmortem CT (PMCT) scans of Indo-Pacific finless porpoises (Neophocaena phocaenoides), this study describes the cross-sectional imaging anatomy of the cetacean abdomino-pelvic organs for the first time.

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Halogenated flame retardants (HFRs) are a large class of chemical additives intended to meet flammability safety requirements, and at present, they are ubiquitous in the environment. Herein, we conducted the target analysis and suspect screening of legacy and novel HFRs and their metabolites in the blubber of finless porpoises (; = 70) and Indo-Pacific humpback dolphins (; = 35) stranded in Hong Kong, a coastal city in the South China Sea, between 2013 and 2020. The average concentrations of total target HFRs (ΣHFRs) were 6.

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Background: Vessel collision induces blunt and sharp force traumas to aquatic animals and is a leading anthropogenic impact affecting cetaceans worldwide. Vessel collision is an important threat affecting vulnerable coastal cetaceans such as the Indo-Pacific humpback dolphins (Sousa chinensis) which reside in coastal waters of Hong Kong amongst heavy marine traffic.

Case Presentation: A severely injured subadult S.

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Nematodes of the genus are parasites that infect various body tissues of cetaceans, including the mammary glands which can influence the reproductive output and hence threaten the survival of endangered cetacean populations. In this study, postmortem computed tomography (PMCT) was used to characterise lesions related to infections in stranded Indo-Pacific finless porpoises () from Hong Kong waters. Using PMCT and subsequently verified by conventional necropsy, -related lesions were found in 52% of finless porpoises examined (n = 13/25), including both males and females.

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We observed contusion-like lesions caused by live sharksucker (Echeneis naucrates) attachment in an Indo-Pacific humpback dolphin (Sousa chinensis). Our report assists in differentiating epidermal lesions for visual health assessment in this vulnerable species and other cetaceans, and this adds new host and epibiont records for E. naucrates and S.

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With 6 years of experience in implementing virtopsy routinely into the Hong Kong cetacean stranding response program, standardized virtopsy procedures, postmortem computed tomography (PMCT) acquisition, postprocessing, and evaluation were successfully established. In this pioneer cetacean virtopsy stranding response program, PMCT was performed on 193 stranded cetaceans, providing postmortem findings to aid necropsy and shed light on the biological health and profile of the animals. This study aimed to assess 8 image rendering techniques in PMCT, including multiplanar reconstruction, curved planar reformation, maximum intensity projection, minimum intensity projection, direct volume rendering, segmentation, transfer function, and perspective volume rendering.

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The preparation of cetacean, in particular baleen whale, skeletons presents a great challenge due to their high lipid content and uncommon size. Documentation of the skeletal morphology is important to produce accurate and reliable models for both research and educational purposes. In this paper, we used a 10.

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Due to the different craniocervical structures in humans and cetaceans, a standardised method assessing the normal craniocervical relationship in cetaceans is lacking, causing difficulties in defining the presence of atlanto-occipital dissociation (AOD) in cetaceans. The present study aimed to 1) describe a novel standardised method of determining the normal craniocervical relationships, and 2) define the 95% accuracy range of the normal craniocervical relationship in finless porpoises (genus Neophocaena), that allowed AOD diagnosis. Fifty-five out 83 stranded or by-caught finless porpoise carcasses were analyzed in term of their craniocervical relationship in dorsal-ventral and medial-lateral dimension, using postmortem computed tomography measurements.

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Databases are systematic tools to archive and manage information related to marine mammal stranding and mortality events. Stranding response networks, governmental authorities and non-governmental organizations have established regional or national stranding networks and have developed unique standard stranding response and necropsy protocols to document and track stranded marine mammal demographics, signalment and health data. The objectives of this study were to (1) describe and review the current status of marine mammal stranding and mortality databases worldwide, including the year established, types of database and their goals; and (2) summarize the geographic range included in the database, the number of cases recorded, accessibility, filter and display methods.

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Article Synopsis
  • Computed tomography (CT) offers a modern, accurate method for measuring the cranial dimensions of cetaceans post-mortem, reducing reliance on traditional manual measurement techniques.
  • A study evaluated CT three-dimensional volume rendered images (3DVRI) from 9 stranded cetaceans, demonstrating high accuracy in cranial measurements (88.05%-99.64%) compared to manual methods.
  • The results showed strong reproducibility and repeatability of the measurements using intraclass correlation coefficients (ICC), suggesting that CT 3DVRI could effectively serve as a reliable alternative for cranial analysis in cetaceans and aid in establishing reference data for research.
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Background: This study aimed to investigate the sonographic appearances of the thyroid glands in nasopharyngeal carcinoma (NPC) patients whose cervical lymph nodes were treated with conventional radiotherapy (RT) or intensity-modulated radiotherapy (IMRT). The post-RT sonographic appearances of the thyroid glands in NPC patients were also correlated with the thyroid function.

Methods: One hundred and three NPC patients who had completed RT of cervical lymph nodes using the anterior cervical field, 30 NPC patients who had completed RT of cervical lymph nodes using IMRT, and 61 healthy subjects were included in the study.

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The mammalian thyroid gland maintains basal metabolism in tissues for optimal function. Determining thyroid volume is important in assessing growth and involution. Volume estimation is also important in stereological studies.

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Objective: To evaluate the use of ultrasonography for thyroid gland assessment in healthy Indo-Pacific bottlenose dolphins (Tursiops aduncus), describe the ultrasonographic appearance of the thyroid gland and adjacent anatomic structures, and identify potential associations between variations in thyroid gland morphology and demographic features in this species.

Animals: 18 captive Indo-Pacific bottlenose dolphins.

Procedures: 1,404 ultrasonographic examinations of the thyroid gland and adjacent anatomic structures (eg, cervical lymph nodes, musculature, and vasculature) were performed during the > 3-year study period.

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Standardization on Shear wave ultrasound elastography (SWUE) technical settings will not only ensure that the results are accurate, but also detect any differences over time that may be attributed to true physiological changes. The present study evaluated the variations of elastic modulus of muscle and tendon using SWUE when different technical aspects were altered. The results of this study indicated that variations of elastic modulus of muscle and tendon were found when different transducer's pressure and region of interest (ROI)'s size were applied.

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Physiologic changes occurring in the thyroid in response to the estrous cycle have been noted in companion animals. However, in bottlenose dolphins, the influence of different reproductive states on thyroid morphology remains unclear. Sonography was used to evaluate the variations of thyroid morphology for nine consecutive estrous cycles of four sexually mature, female Indo-Pacific bottlenose dolphins (Tursiops aduncus).

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The assessment of thyroid volume plays an indispensable role in the diagnosis and management of different thyroid diseases. The present study evaluates the accuracy of dolphin thyroid volume measurement as determined by four two-dimensional (2D) ultrasound methods (A-D), with a standard of reference using three-dimensional (3D) ultrasound. The measurement accuracy for different recognized thyroid configuration is also evaluated.

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Measurement of thyroid size and volume is a useful clinical parameter in both human and veterinary medicine, particularly for diagnosing thyroid diseases and guiding corrective therapy. Procuring a fully-equipped clinical ultrasound unit (FCUS) may be difficult in most veterinary settings. The present study evaluated the inter-equipment variability in dolphin thyroid ultrasound measurements between a portable ultrasound unit (PUS) and a FCUS; for both units, repeatability was also assessed.

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Purpose: To evaluate the accuracy and reliability of two 3-dimensional (3D) ultrasound imaging and measurement techniques in volume measurements using custom-made phantoms.

Methods: A total of 20 phantoms with irregular-shaped test objects of known volume (2-9.7 ml) were constructed.

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Volumetric measurement is useful in the clinical practice as it can accurately assess the size of organs and lesions, which aids diagnosis and monitoring of treatment response. This in vitro study was undertaken to evaluate and compare the accuracy of three-dimensional ultrasound (3D-US) volumetric measurements using different numbers of image planes for outlining the region-of-interest. A total of 20 tissue phantoms (10 with regular and 10 with irregular tissue specimens) with known volume (2.

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