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Górski K, Borowska M, Turek B, Pawlikowski M, Jankowski K, Bereznowski A, Polkowska I, Domino M. An application of the density standard and scaled-pixel-counting protocol to assess the radiodensity of equine incisor teeth affected by resorption and hypercementosis: preliminary advancement in dental radiography. BMC Vet Res 2023; 19:116. [PMID: 37559089 PMCID: PMC10413604 DOI: 10.1186/s12917-023-03675-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 07/24/2023] [Indexed: 08/11/2023] Open
Abstract
BACKGROUND Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH) syndrome is a dental disease where the radiographic signs may be quantified using radiographic texture features. This study aimed to implement the scaled-pixel-counting protocol to quantify and compare the image structure of teeth and the density standard in order to improve the identification of the radiographic signs of tooth resorption and hypercementosis using the EOTRH syndrome model. METHODS AND RESULTS A detailed examination of the oral cavity was performed in 80 horses and maxillary incisor teeth were evaluated radiographically, including an assessment of the density standard. On each of the radiographs, pixel brightness (PB) was extracted for each of the ten steps of the density standard (S1-S10). Then, each evaluated incisor tooth was assigned to one of 0-3 EOTRH grade-related groups and annotated using region of interest (ROI). For each ROI, the number of pixels (NP) from each range was calculated. The linear relation between an original X-ray beam attenuation and PB was confirmed for the density standard. The NP values increased with the number of steps of the density standard as well as with EOTRH degrees. Similar accuracy of the EOTRH grade differentiation was noted for data pairs EOTRH 0-3 and EOTRH 0-1, allowing for the differentiation of both late and early radiographic signs of EOTRH. CONCLUSION The scaled-pixel-counting protocol based on the use of density standard has been successfully implemented for the differentiation of radiographic signs of EOTRH degrees.
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Affiliation(s)
- Kamil Górski
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences (WULS - SGGW), Nowoursynowska 100, 02-797, Warsaw, Poland
| | - Marta Borowska
- Institute of Biomedical Engineering, Faculty of Mechanical Engineering, Białystok University of Technology, Wiejska 45C, 15-351, Bialystok, Poland
| | - Bernard Turek
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences (WULS - SGGW), Nowoursynowska 100, 02-797, Warsaw, Poland
| | - Marek Pawlikowski
- Institute of Mechanics and Printing, Warsaw University of Technology, Narbutta 85, 02-524, Warsaw, Poland
| | - Krzysztof Jankowski
- Institute of Mechanics and Printing, Warsaw University of Technology, Narbutta 85, 02-524, Warsaw, Poland
| | - Andrzej Bereznowski
- Division of Veterinary Epidemiology and Economics, Institute of Veterinary Medicine, Warsaw University of Life Sciences, Nowoursynowska 159C, 02-776, Warsaw, Poland
| | - Izabela Polkowska
- Department and Clinic of Animal Surgery, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Głęboka 30, 20-950, Lublin, Poland
| | - Małgorzata Domino
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences (WULS - SGGW), Nowoursynowska 100, 02-797, Warsaw, Poland.
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Albers L, Albers J, Dullin C, Staszyk C, Bienert-Zeit A. Early incisor lesions and Equine Odontoclastic Tooth Resorption and Hypercementosis: Reliability of radiographic findings. Equine Vet J 2023; 55:261-269. [PMID: 35302672 DOI: 10.1111/evj.13577] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 02/19/2022] [Accepted: 03/10/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND In clinical practice, early diagnosis of Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH) and other resorptive incisor diseases is difficult to achieve. The radiographic appearance of subtle pathological changes has not been described in detail and might be confused with age-related changes. OBJECTIVES The study was performed to define typical radiographic signs of early incisor lesions and to evaluate the reliability of the radiographic findings. STUDY DESIGN Descriptive and comparative study using post mortem clinical, radiographic, macroscopic and µCT examination. METHODS The incisor region of 20 cadaveric horse heads, divided into three different age groups, was examined visually and by palpation. Intraoral radiographs were taken. After extraction, each incisor was macroscopically evaluated. Micro-computed tomography (µCT) scans were obtained. These scans were processed with Scry (v6.0, Kuchel & Sautter GbR) to obtain surface meshes which then were transferred to Meshlab (ISTI-CNR, version 2016.12). Attached tissues were virtually removed and surface curvature was computed to visualise and evaluate the quantity of unevenness (roughness) of the teeth's surface. Scoring systems for each diagnostic modality were developed. Scores were compared to describe and evaluate the radiographic appearance of early incisor lesions. RESULTS The prevalence and severity of incisor lesions increased with age. Early, subtle lesions develop on the palatal/lingual side of incisors. While radiographically detected lesions were confirmed macroscopically and on the µCT scans, numerous teeth which were radiographically classified as healthy displayed lesions by macroscopic inspection (13.7%) and µCT analysis (58.1%). MAIN LIMITATIONS Cadavers were studied and dental history was unknown. CONCLUSIONS The detection of early and subtle incisor lesions indicating first signs of EOTRH on dorsoventral intraoral radiographs is limited due to the typical localisation of the lesions on the palatal/lingual side of the incisors.
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Affiliation(s)
- Louisa Albers
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Jonas Albers
- Institute for Diagnostic and Interventional Radiology, University Medical Centre Göttingen, Göttingen, Germany
| | - Christian Dullin
- Institute for Diagnostic and Interventional Radiology, University Medical Centre Göttingen, Göttingen, Germany
| | - Carsten Staszyk
- Faculty of Veterinary Medicine, Institute of Veterinary-Anatomy, -Histology and -Embryology, Justus-Liebig-University Gießen, Gießen, Germany
| | - Astrid Bienert-Zeit
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
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ICRP PUBLICATION 153 Approved by the Commission in September 2022. Ann ICRP 2022; 51:9-95. [PMID: 36942865 DOI: 10.1177/01466453221142702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
Veterinary use of radiation in the diagnosis, management, and treatment of disease has expanded and diversified, as have the corresponding radiological protection concerns. Radiological exposure of personnel involved in veterinary procedures and, where applicable, members of the public providing assistance (e.g. owners or handlers) has always been included within the system of radiological protection. Veterinary practice is now addressed explicitly as the modern complexities associated with this practice warrant dedicated consideration, and there is a need to clarify and strengthen the application of radiological protection principles in this area. The Commission recommends that the system of radiological protection should be applied in veterinary practice principally for the protection of humans, but with explicit attention to the protection of exposed animals. Additionally, consideration should be given to the risk of potential contamination of the environment associated with applications of nuclear medicine in veterinary practice. This publication focuses primarily on justification and optimisation in veterinary practice, and sets the scene for more detailed guidance to follow in future Recommendations. It is intended for a wide-ranging audience, including radiological protection professionals, veterinary staff, students, education and training providers, and members of the public, as an introduction to radiological protection in veterinary practice.© 2022 ICRP. Published by SAGE.
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Górski K, Borowska M, Stefanik E, Polkowska I, Turek B, Bereznowski A, Domino M. Application of Two-Dimensional Entropy Measures to Detect the Radiographic Signs of Tooth Resorption and Hypercementosis in an Equine Model. Biomedicines 2022; 10:2914. [PMID: 36428482 PMCID: PMC9687516 DOI: 10.3390/biomedicines10112914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 10/28/2022] [Accepted: 11/11/2022] [Indexed: 11/16/2022] Open
Abstract
Dental disorders are a serious health problem in equine medicine, their early recognition benefits the long-term general health of the horse. Most of the initial signs of Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH) syndrome concern the alveolar aspect of the teeth, thus, the need for early recognition radiographic imaging. This study is aimed to evaluate the applicability of entropy measures to quantify the radiological signs of tooth resorption and hypercementosis as well as to enhance radiographic image quality in order to facilitate the identification of the signs of EOTRH syndrome. A detailed examination of the oral cavity was performed in eighty horses. Each evaluated incisor tooth was assigned to one of four grade-related EOTRH groups (0-3). Radiographs of the incisor teeth were taken and digitally processed. For each radiograph, two-dimensional sample (SampEn2D), fuzzy (FuzzEn2D), permutation (PermEn2D), dispersion (DispEn2D), and distribution (DistEn2D) entropies were measured after image filtering was performed using Normalize, Median, and LaplacianSharpening filters. Moreover, the similarities between entropy measures and selected Gray-Level Co-occurrence Matrix (GLCM) texture features were investigated. Among the 15 returned measures, DistEn2D was EOTRH grade-related. Moreover, DistEn2D extracted after Normalize filtering was the most informative. The EOTRH grade-related similarity between DistEn2D and Difference Entropy (GLCM) confirms the higher irregularity and complexity of incisor teeth radiographs in advanced EOTRH syndrome, demonstrating the greatest sensitivity (0.50) and specificity (0.95) of EOTRH 3 group detection. An application of DistEn2D to Normalize filtered incisor teeth radiographs enables the identification of the radiological signs of advanced EOTRH with higher accuracy than the previously used entropy-related GLCM texture features.
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Affiliation(s)
- Kamil Górski
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland; (E.S.); (B.T.)
| | - Marta Borowska
- Institute of Biomedical Engineering, Faculty of Mechanical Engineering, Białystok University of Technology, 15-351 Bialystok, Poland;
| | - Elżbieta Stefanik
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland; (E.S.); (B.T.)
| | - Izabela Polkowska
- Department and Clinic of Animal Surgery, Faculty of Veterinary Medicine, University of Life Sciences, 20-950 Lublin, Poland;
| | - Bernard Turek
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland; (E.S.); (B.T.)
| | - Andrzej Bereznowski
- Division of Veterinary Epidemiology and Economics, Institute of Veterinary Medicine, Warsaw University of Life Sciences, Nowoursynowska 159c, 02-776 Warsaw, Poland;
| | - Małgorzata Domino
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland; (E.S.); (B.T.)
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Fairburn AJ, Meehan LJ, Roberts VLH. Computed tomographic findings in 101 horses presented for the investigation of headshaking. EQUINE VET EDUC 2022. [DOI: 10.1111/eve.13718] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Alison J. Fairburn
- Bristol Veterinary School University of Bristol Somerset UK
- Bell Equine Veterinary Clinic, Mereworth Kent UK
| | - Lucinda Jayne Meehan
- Bristol Veterinary School University of Bristol Somerset UK
- VetCT, St. John's Innovation Centre Cambridge UK
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Brounts SH, Lund JR, Whitton RC, Ergun DL, Muir P. Use of a novel helical fan beam imaging system for computed tomography of the distal limb in sedated standing horses: 167 cases (2019–2020). J Am Vet Med Assoc 2022; 260:1351-1360. [DOI: 10.2460/javma.21.10.0439] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Abstract
OBJECTIVE
To evaluate the diagnostic capabilities of a novel helical fan beam CT system used for imaging of horses with a range of clinical distal limb problems.
ANIMALS
167 horses.
PROCEDURES
Medical records were reviewed of horses presented for CT of the distal limb at 2 university-based veterinary hospitals. The following data were recorded: age, sex, breed, presenting complaint, sedation used for imaging, scanning time, procedure time, other diagnostic imaging methods performed, imaging diagnosis, clinical diagnosis, and complications during imaging.
RESULTS
Most horses were Thoroughbreds and Quarter Horses. Procedure times ranged from 15 to 40 minutes, with scanning completed in 15 to 45 seconds for each region of interest. The foot or pastern region was commonly scanned (88/167 [53%] horses), with navicular bone disease diagnosed in 42 of 88 (48%) horses. The fetlock region was also commonly scanned (42/167 [40%] horses), with palmar or plantar osteochondral disease diagnosed in 17 of 42 (40%) horses. Horses were compliant during scanning, and no complications with sedation or damage to the scanner occurred. A specific imaging diagnosis for the lameness was achieved more frequently with CT imaging (166/167 [99%]) than with planar digital radiography (26/58 [45%]).
CLINICAL RELEVANCE
The helical fan beam CT system could be used safely to scan sedated standing horses from the carpal or tarsal region distally. Subjectively, the machine was easy to operate, allowing CT to be incorporated into lameness investigations. CT imaging was very likely to result in a clinical diagnosis in horses with distal limb lameness.
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Affiliation(s)
- Sabrina H. Brounts
- Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI
| | - Jane R. Lund
- Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI
| | - R. Chris Whitton
- Department of Veterinary Clinical Sciences, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Werribee, Australia
| | - David L. Ergun
- Department of Medical Physics, University of Wisconsin, Madison, WI
- Asto CT Inc, Middleton, WI
| | - Peter Muir
- Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI
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Brounts SH, Henry T, Lund JR, Whitton RC, Ergun DL, Muir P. Use of a novel helical fan beam imaging system for computed tomography of the head and neck in sedated standing horses: 120 cases (2019–2020). J Am Vet Med Assoc 2022; 260:1361-1368. [DOI: 10.2460/javma.21.10.0471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
OBJECTIVE
To evaluate the diagnostic capabilities of a novel helical fan beam CT system used for imaging of horses with clinical problems of the head and neck.
ANIMALS
120 horses.
PROCEDURES
Medical records were reviewed of horses presented for CT of the head or neck at 2 university hospitals. The following data were recorded: age, sex, breed, presenting complaint, sedation used for imaging, scanning time, procedure time, other diagnostic imaging methods performed, imaging diagnosis, clinical diagnosis, and complications during imaging.
RESULTS
Quarter Horses and Warmbloods were the most common breeds, and the most common complaint was nasal discharge. The head (101/120 [84%] horses) was scanned most frequently, and the most common diagnoses were primary dental disease and a space-occupying lesion of the paranasal sinuses. Nuchal bursitis was the most common imaging diagnosis in the neck region. Procedure time ranged from 20 to 45 minutes with a scanning time of 30 to 40 seconds. No complications with horse sedation occurred, and horses tolerated scanning well. An imaging diagnosis was more frequently achieved with CT (109/120 [91%] horses) than with planar digital radiography (23/61 [38%] horses).
CLINICAL RELEVANCE
The helical fan beam CT system had fast scanning times and could be used safely for routine imaging of the teeth and sinuses in horses. The caudal extent of scanning in the neck region was limited by the shape of the horse’s neck and thorax.
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Affiliation(s)
- Sabrina H. Brounts
- Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI
| | | | - Jane R. Lund
- Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI
| | - R. Chris Whitton
- Department of Veterinary Clinical Sciences, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Werribee, Australia
| | - David L. Ergun
- Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI
- Asto CT Inc, Middleton, WI
| | - Peter Muir
- Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI
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Yitbarek D, Dagnaw GG. Application of Advanced Imaging Modalities in Veterinary Medicine: A Review. Vet Med (Auckl) 2022; 13:117-130. [PMID: 35669942 PMCID: PMC9166686 DOI: 10.2147/vmrr.s367040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 05/26/2022] [Indexed: 11/28/2022]
Abstract
Veterinary anatomy has traditionally relied on detailed dissections to produce anatomical illustrations, but modern imaging modalities, now represent an enormous resource that allows for fast non-invasive visualizations in living animals for clinical and research purposes. In this review, advanced anatomical imaging modalities and their applications, safety issues, challenges, and future prospects of the techniques commonly employed for animal imaging would be highlighted. The quality of diagnostic imaging equipment in veterinary practice has greatly improved. Recent advances made in veterinary advanced imaging specifically about cross-sectional modalities (CT and MRI), nuclear medicine (PET, SPECT), and dual imaging modalities (PET/CT, PET/MR, and SPECT/CT) have become widely available, leading to greater demands and expectations from veterinary clients. These modalities allow for the creation of three-dimensional representations that can be of considerable value in the dissemination of clinical diagnosis and anatomical studies. Despite, the modern imaging modalities well established in developed countries across the globe, it is yet to remain in its infancy stage in veterinary practice in developing countries due to heavy initial investment and maintenance costs, lack of expert interpretation, a requirement of specialized technical staff and need of adjustable machines to accommodate the different range of animal sizes. Therefore, veterinarians should take advantage of these imaging techniques in designing future experiments by considering the availability of these varied imaging modalities and the creation of three-dimensional graphical representations of internal structures.
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Affiliation(s)
| | - Gashaw Getaneh Dagnaw
- Department of Biomedical Sciences, College of Veterinary Medicine and Animal Sciences, University of Gondar, Gondar, Ethiopia
- Correspondence: Gashaw Getaneh Dagnaw, Department of Biomedical Sciences, College of Veterinary Medicine and Animal Sciences, University of Gondar, P.O. Box: 196, Gondar, Ethiopia, Email
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Stieger-Vanegas SM, Hanna AL. The Role of Computed Tomography in Imaging Non-neurologic Disorders of the Head in Equine Patients. Front Vet Sci 2022; 9:798216. [PMID: 35321060 PMCID: PMC8936190 DOI: 10.3389/fvets.2022.798216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 02/08/2022] [Indexed: 11/13/2022] Open
Abstract
Computed tomography (CT) imaging of the head in equine patients is now commonly performed as CT scanners are more readily available. Head CT has proven valuable in evaluating spatially complex anatomic structures, where radiographic superimposition, or restricted access via endoscopy or ultrasound, limit complete evaluation of the disease process. Head CT has been demonstrated to be incredibly valuable in the evaluation of dental and paranasal sinus disease, disease of the hyoid apparatus and ear, and in evaluation of skull trauma. CT is an excellent modality for assessment of both osseous and soft tissue structures; however, evaluation of complex vascular anatomy and determination of tissue viability is limited without the use of contrast agents. Therefore, various contrast agent protocols including intravenous and intraarterial iodinated contrast administration techniques have been established. CT also has limitations in the evaluation of brain and spinal cord disease, for which magnetic resonance imaging (MRI) has major advantages. Head CT images are most commonly evaluated in transverse planes. However, standard multiplanar reconstructions of the head including dorsal and parasagittal planes improve the understanding of spatially complex disease processes. These reconstructions can be crucial for accurate identification of diseased teeth and determination of the extent and severity of osseous and paranasal sinus disease. Head CT examinations are becoming an increasingly important diagnostic tool in the evaluation of horses with head disorders, and CT imaging findings are an important aspect in the clinical decision-making process. The following review discusses the indications, benefits, and technical considerations for the use of computed tomography (CT) in evaluating non-neurologic head pathologies in equine patients.
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Affiliation(s)
- Susanne M. Stieger-Vanegas
- Department of Clinical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR, United States
- *Correspondence: Susanne M. Stieger-Vanegas
| | - Ashley L. Hanna
- College of Veterinary Medicine, Washington State University, Pullman, WA, United States
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10
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Kozłowska N, Wierzbicka M, Jasiński T, Domino M. Advances in the Diagnosis of Equine Respiratory Diseases: A Review of Novel Imaging and Functional Techniques. Animals (Basel) 2022; 12:381. [PMID: 35158704 PMCID: PMC8833607 DOI: 10.3390/ani12030381] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 02/02/2022] [Accepted: 02/03/2022] [Indexed: 02/04/2023] Open
Abstract
The horse, as a flight animal with a survival strategy involving rapid escape from predators, is a natural-born athlete with enormous functional plasticity of the respiratory system. Any respiratory dysfunction can cause a decline in ventilation and gas exchange. Therefore, respiratory diseases often lead to exercise intolerance and poor performance. This is one of the most frequent problems encountered by equine internists. Routine techniques used to evaluate respiratory tract diseases include clinical examination, endoscopic examination, radiographic and ultrasonographic imaging, cytological evaluation, and bacterial culture of respiratory secretions. New diagnostic challenges and the growing development of equine medicine has led to the implementation of advanced diagnostic techniques successfully used in human medicine. Among them, the use of computed tomography (CT) and magnetic resonance (MR) imaging significantly broadened the possibilities of anatomical imaging, especially in the diagnosis of upper respiratory tract diseases. Moreover, the implementation of spirometry, electrical impedance tomography (EIT), and impulse oscillation system (IOS) sheds new light on functional diagnostics of respiratory tract diseases, especially those affecting the lower part. Therefore, this review aimed to familiarize the clinicians with the advantages and disadvantages of the advanced diagnostic techniques of the equine respiratory tract and introduce their recent clinical applications in equine medicine.
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Affiliation(s)
| | - Małgorzata Wierzbicka
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland; (N.K.); (T.J.)
| | | | - Małgorzata Domino
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland; (N.K.); (T.J.)
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Herren FL, Gerber V, Meier R, Schweizer-Gorgas D, Klopfenstein Bregger MD. Semi-Automatic Segmentation of Cone Beam Computed Tomography Datasets for Volume Measurements of Equine Cheek Teeth. J Vet Dent 2021; 39:41-48. [PMID: 34866465 DOI: 10.1177/08987564211061630] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The volumes of equine teeth may change considerably over time for several reasons including domestication, routine dental floating, and the hypsodont and anelodont nature of the teeth. Cone beam computed tomography (CBCT) of the head is routinely performed in standing horses and, in this proof of concept study, the feasibility of measuring tooth volume from CBCT datasets was determined. The CBCT images of 5 equine cadaver cheek teeth were segmented with a software 3-dimensional (3D) Slicer using a predefined protocol, corrected manually, and re-assembled into a 3D model. Individual tooth volume (VS) was calculated from the model. After extraction, the volumes were also measured using the "gold-standard" water displacement method (VW) for comparison. The VS of 77 teeth ranged from 7114 to 42,300 mm3 which strongly correlated with VW (r = 0.99), and on average VS was 6.1% less than VW. There was no significant difference in VS between the right and left arcades in individual animals. Maxillary cheek tooth volume was on average 40% larger than it was for mandibular counterparts. Semi-automatic image segmentation of equine cheek teeth from CBCT data is feasible and accurate but requires some manual intervention. This preliminary study provides initial data on the volume of equine cheek teeth and creates new possibilities for future in vivo studies.
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Affiliation(s)
- Fabienne L Herren
- 455022Swiss Institute of Equine Medicine (ISME), Department of Clinical Veterinary Medicine, Vetsuisse-Faculty, University of Bern, and Agroscope Avenches, Bern, Switzerland
| | - Vinzenz Gerber
- 455022Swiss Institute of Equine Medicine (ISME), Department of Clinical Veterinary Medicine, Vetsuisse-Faculty, University of Bern, and Agroscope Avenches, Bern, Switzerland
| | - Raphael Meier
- University Institute of Diagnostic and Interventional Neuroradiology, University Hospital Inselspital and University of Bern, Bern, Switzerland
| | | | - Micaël D Klopfenstein Bregger
- 455022Swiss Institute of Equine Medicine (ISME), Department of Clinical Veterinary Medicine, Vetsuisse-Faculty, University of Bern, and Agroscope Avenches, Bern, Switzerland
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12
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Bryant B, Meehan LJ, Roberts V. Position of the midline septum of the guttural pouches in horses subjected to computed tomography. J Equine Vet Sci 2021; 103:103670. [PMID: 34281636 DOI: 10.1016/j.jevs.2021.103670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/24/2021] [Accepted: 05/24/2021] [Indexed: 11/19/2022]
Abstract
Standing computed tomographic (CT) examination of the equine guttural pouch frequently reveals deviation of the midline septum. The significance of deviation is currently unknown. The aims of this retrospective, single-centre study were to determine the prevalence of deviation of the midline septum of the guttural pouch and determine whether there was an association between the presence and degree of deviation of the septum, and guttural pouch disease. Case records were reviewed, identifying 95 horses that had undergone a standing, sedated, head CT and guttural pouch endoscopy. The presence, laterality, subjective degree and angle of deviation of the midline septum on CT was recorded. A total of 69 (72.6%) horses were identified with deviation of the midline septum, with the mean angle of deviation 13.4o and a maximum deviation of 52.6o. No significant association between the presence of deviation of the midline septum (P = .722) or severity of deviation (P = .428) and an endoscopic abnormality within the guttural pouch was found. The laterality of deviation and guttural pouch abnormalities were also not associated (P = .000). Deviation of the midline septum of the guttural pouch is a common finding on CT examination, and does not have clinical significance in this study.
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13
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van Zadelhoff C, Liuti T, Dixon PM, Reardon RJM. Multidetector CT and cone-beam CT have substantial agreement in detecting dental and sinus abnormalities in equine cadaver heads. Vet Radiol Ultrasound 2021; 62:413-420. [PMID: 33987964 DOI: 10.1111/vru.12978] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 02/27/2021] [Accepted: 03/25/2021] [Indexed: 11/30/2022] Open
Abstract
The performance of cone-beam CT (CBCT) systems compared to conventional helical multidetector CT (MDCT) imaging of the equine head is unknown. The aim of this prospective, method-comparison study was to compare the ability of CBCT and MDCT to detect abnormalities in equine cadaver heads. Eleven equine cadaver heads were scanned using a CBCT scanner and a 64-slice MDCT scanner. Consensus evaluations for CBCT and MDCT scans were performed by three observers. Identified abnormalities were grouped into subcategories with a focus on dental abnormalities. Kappa agreement values between detected abnormalities for CBCT and MDCT methods were calculated. Of 468 teeth evaluated, 122 (26.1%) were found to have abnormalities (including in 58 infundibula and 7 pulps) using MDCT and 105 (22.4%) were found to have abnormalities (including in 52 infundibula and 2 pulps) using CBCT. The agreement between CBCT and MDCT was almost perfect for overall detection of dental abnormalities (k = 0.90) with k = 1 for diastema k = 0.95 for clinical crown abnormalities, and k = 0.93 for infundibular abnormalities. However, the detection of pulp changes by CBCT was only moderate k = 0.44. Increased scatter radiation, non-calibrated Hounsfield Unit and artefacts in CBCT images made accurate identification of the pulp density difficult. In conclusion, CBCT results were similar to conventional MDCT for the majority of dental abnormalities, however, pulp abnormalities were not reliably identified using CBCT, potentially limiting its clinical use for detecting endodontic disease in its current form. Further comparison with more cases with confirmed dental disease and studies in clinical cases are warranted.
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Affiliation(s)
- Claudia van Zadelhoff
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Estate, Roslin, UK
| | - Tiziana Liuti
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Estate, Roslin, UK
| | - Padraic M Dixon
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Estate, Roslin, UK
| | - Richard J M Reardon
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Estate, Roslin, UK
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Pauwels FE, Van der Vekens E, Christan Y, Koch C, Schweizer D. Feasibility, indications, and radiographically confirmed diagnoses of standing extremity cone beam computed tomography in the horse. Vet Surg 2021; 50:365-374. [PMID: 33421172 DOI: 10.1111/vsu.13560] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 10/08/2020] [Accepted: 11/28/2020] [Indexed: 01/22/2023]
Abstract
OBJECTIVE To report on the feasibility, indications, and diagnostic yield of cone beam computed tomography (CBCT) of horses' extremities performed under standing sedation. STUDY DESIGN Retrospective clinical case series. SAMPLE POPULATION Fifty-nine CBCT examinations in 58 horses. METHODS Examinations were categorized for indications for CBCT dependent on a suspicion, presence, or absence of a diagnosis prior to CBCT. The number of acquisitions per examination, total time for the examination, diagnostic score of each acquisition (diagnostic, diagnostic-compromised, nondiagnostic), and additional diagnostic information regarding preexisting diagnostic information were recorded. RESULTS Three (median) acquisitions were performed per examination in a median study time of 14 minutes. In 24 of 33 cases with a suspected diagnosis, this diagnosis was confirmed or definitively refuted; in seven of 33 cases, the suspected diagnosis was refuted without a new diagnosis; and, in two of 33 cases, the suspected diagnosis could not be confirmed nor could a new diagnosis be made. In five of nine cases without a preexisting diagnosis, a diagnosis was established. In 16 cases with a diagnosis prior to CBCT, additional information was recorded, or a surgical plan was prepared. In 14 of 18 cases in which additional contrast techniques were used, additional information was gained. CONCLUSION Standing CBCT of the horses' extremities is feasible and can produce diagnostic information in a timely fashion. CLINICAL SIGNIFICANCE The results provide evidence of the practicality and diagnostic potential of standing CBCT of horses' extremities.
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Affiliation(s)
- Frederik E Pauwels
- Department of Clinical Veterinary Medicine, Division of Clinical Radiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Elke Van der Vekens
- Department of Clinical Veterinary Medicine, Division of Clinical Radiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Yan Christan
- Swiss Institute of Equine Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland.,Agroscope, Switzerland, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
| | - Christoph Koch
- Swiss Institute of Equine Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Daniela Schweizer
- Department of Clinical Veterinary Medicine, Division of Clinical Radiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
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15
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Mageed M. Standing computed tomography of the equine limb using a multi‐slice helical scanner: Technique and feasibility study. EQUINE VET EDUC 2020. [DOI: 10.1111/eve.13388] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- M. Mageed
- Tierklinik Lüsche GmbH Bakum‐Lüsche Germany
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16
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Epperly E, Whitty JA. Equine Imaging: Computed Tomography Interpretation. Vet Clin North Am Equine Pract 2020; 36:527-543. [PMID: 33067100 DOI: 10.1016/j.cveq.2020.08.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Computed tomography (CT) has revolutionized the veterinarian's ability to image the equine skull and led to improved diagnostic accuracy and clarity for surgical planning. The increased cost for this evaluation is offset by more accurate diagnosis and targeted therapy. As novel technology is developed that allows for increased availability of equine head, the price will continue to decrease and more examinations will be performed. New skills are needed for the veterinarian to accurately interpret this modality. This article reviews the normal CT appearance of the equine skull and presents examples and key features of several common diseases.
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Affiliation(s)
- Erin Epperly
- Cornell University College of Veterinary Medicine, 930 Campus Road, Box 25, Ithaca, NY 14853, USA.
| | - Justin A Whitty
- Department of Clinical Sciences, Cornell University College of Veterinary Medicine, 930 Campus Road, Box 25, Ithaca, NY 14853, USA
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17
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Dubois BB, Dixon JJ, Witte TH. Assessment of clinical and computed tomographic findings for association with the outcome of intraoral cheek tooth extraction in horses and ponies. J Am Vet Med Assoc 2020; 255:1369-1376. [PMID: 31793834 DOI: 10.2460/javma.255.12.1369] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To describe clinical and CT findings for horses and ponies undergoing intraoral cheek tooth extraction and assess potential associations between these features and outcome of the procedure. ANIMALS 74 horses and 7 ponies. PROCEDURES Medical records were searched to identify horses and ponies that underwent CT and intraoral extraction of ≥ 1 cheek tooth with standing sedation. Signalment and clinical variables were recorded, and CT scans were reviewed. Anatomic location and measurements of affected teeth; abnormalities of the periodontium, pulp, infundibula, roots, and tooth shape; fracture presence and type; presence of sinusitis; and affected sinus cavities were assessed by a surgeon and a radiologist. Intraoral extraction outcome was recorded as successful (complete removal of the tooth in 1 intraoral extraction procedure) or unsuccessful. Univariable and multivariable logistic regression analyses were performed to assess associations between clinical or CT findings and outcome. RESULTS 89 cheek teeth (80 maxillary and 9 mandibular) were included in the analyses. Sixty of 89 (67%) cheek teeth were extracted successfully (56/80 [70%] maxillary and 4/9 [44%] mandibular cheek teeth). Only presence of a simple fracture (vs no fracture) was associated with outcome on multivariable regression analysis; odds of successful intraoral extraction were significantly lower when this feature was present. CONCLUSIONS AND CLINICAL RELEVANCE Most extractions of cheek teeth in the study sample were successful, and results may be useful for practitioners in refining cheek tooth extraction plans for horses and ponies. Further studies are required to assess whether specific CT findings can be used to predict the outcome of intraoral extraction in equids.
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18
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Koch C, Pauwels F, Schweizer‐Gorgas D. Technical set‐up and case illustrations of orthopaedic cone beam computed tomography in the standing horse. EQUINE VET EDUC 2020. [DOI: 10.1111/eve.13290] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- C. Koch
- Department of Clinical Veterinary Medicine Vetsuisse Faculty Swiss Institute of Equine Medicine (ISME) Agroscope University of Bern Bern Switzerland
| | - F. Pauwels
- Division of Clinical Radiology, Vetsuisse Faculty University of Bern Bern Switzerland
| | - D. Schweizer‐Gorgas
- Division of Clinical Radiology, Vetsuisse Faculty University of Bern Bern Switzerland
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19
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Lloyd-Edwards RA, Willems DS, Beukers M, van den Brom-Spierenburg A, Vernooij JCM, Veraa S. Presumed cholesterinic granulomas detected on CT in horses are associated with increased lateral ventricle height and age. Vet Radiol Ultrasound 2020; 61:269-278. [PMID: 32020759 PMCID: PMC7317960 DOI: 10.1111/vru.12847] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 10/19/2019] [Accepted: 11/19/2019] [Indexed: 11/29/2022] Open
Abstract
Cholesterinic granulomas are mass‐like lesions that form at the choroid plexus of the ventricular system. Large cholesterinic granulomas within the lateral ventricles have been reported to cause severe neurological signs. However, little data are available about their prevalence or appearance in the overall population. The objective was to report the prevalence of presumed cholesterinic granulomas on CT in a population of horses, and investigate associations between presumed cholesterinic granuloma presence, lateral ventricle size, age, and neurological signs. The study was cross sectional, CT scans of the head were assessed for presumed cholesterinic granuloma presence and size, and lateral ventricle height. Computed tomography findings and clinical information were compared using nonparametric testing. Computed tomography scans of 139 horses were included. Presumed cholesterinic granulomas were found in 22 horses (15.8%), nine were unilateral and 13 bilateral. A significant increase in prevalence was observed with age (P < .0001), with 38% of horses over 15 years old affected. The median volume of presumed cholesterinic granulomas was 242 mm3 with a range from 51 to 2420 mm3. The mean lateral ventricle height was significantly increased in horses with presumed cholesterinic granulomas present (P = .004), with a median of 7.3 mm compared to 4.9 mm without. Neurological signs were not associated with presumed cholesterinic granuloma presence or lateral ventricle height. Fourth ventricle mineralizations were found in seven horses, which may represent cholesterinic granulomas. In conclusion, presumed cholesterinic granulomas occurred in a large proportion of the examined population and are associated with increased lateral ventricle dilation and advanced age.
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Affiliation(s)
- Ralph A Lloyd-Edwards
- Division of Diagnostic Imaging, Faculty of Veterinary Medicine, Utrecht, The Netherlands
| | - Dorien S Willems
- Division of Diagnostic Imaging, Faculty of Veterinary Medicine, Utrecht, The Netherlands
| | - Martijn Beukers
- Division of Diagnostic Imaging, Faculty of Veterinary Medicine, Utrecht, The Netherlands
| | | | - Johannes C M Vernooij
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Stefanie Veraa
- Division of Diagnostic Imaging, Faculty of Veterinary Medicine, Utrecht, The Netherlands
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20
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Davies T, Skelly C, Puggioni A, D'Helft C, Connolly S, Hoey S. Standing CT of the equine head: Reducing radiation dose maintains image quality. Vet Radiol Ultrasound 2019; 61:137-146. [PMID: 31823453 DOI: 10.1111/vru.12823] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 08/26/2019] [Accepted: 09/07/2019] [Indexed: 12/15/2022] Open
Abstract
Multiple published studies involving computed tomographic (CT) examinations of the equine head utilise a wide range of mAs parameters for image acquisition. This prospective, experimental study assessed the effects of lowering mAs during CT image acquisition on image quality and scatter radiation on 10 cadaver equine heads. Each head was scanned three times at 300, 225, and 150 mAs, with all other scanning parameters remaining constant between series. An anthropomorphic phantom was positioned adjacent to each equine head during image acquisition, mimicking a human bystander, with an ionization chamber attached to the phantom at eye level. Each series was reconstructed using filtered back projection, using medium (H30) and high (H80) frequency reconstruction algorithms. Quantitative image quality assessment was performed by calculating signal to noise ratio (SNR) and contrast to noise ratio (CNR). Two qualitative image quality assessments were performed independently by three blinded board certified veterinary radiologists with a 4 week interval, using a visual grade analysis model adapted from peer reviewed medical literature. Ionization chamber measurements, calculated volume CT dose index (CTDIvol), and dose-length product (DLP) were recorded. Halving radiation dose during image acquisition from 300 to 150mAs resulted in comparable image quality between series. There was a statistically significant and linear relationship between mAs and scatter radiation to the bystander; halving mAs during image acquisition resulted in halving of scatter radiation. Results of this cadaveric study support the use of lower mAs settings during standing CT examinations of the equine head.
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Affiliation(s)
- Thomas Davies
- Diagnostic Imaging Department, UCD Veterinary Hospital, University College Dublin, Dublin, Ireland
| | - Cliona Skelly
- Diagnostic Imaging Department, UCD Veterinary Hospital, University College Dublin, Dublin, Ireland
| | - Antonella Puggioni
- Diagnostic Imaging Department, UCD Veterinary Hospital, University College Dublin, Dublin, Ireland
| | - Catherine D'Helft
- Diagnostic Imaging Department, UCD Veterinary Hospital, University College Dublin, Dublin, Ireland
| | | | - Seamus Hoey
- Diagnostic Imaging Department, UCD Veterinary Hospital, University College Dublin, Dublin, Ireland
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21
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Röttiger C, Hellige M, Ohnesorge B, Bienert-Zeit A. Magnetic resonance imaging and computed tomography of equine cheek teeth and adjacent structures: comparative study of image quality in horses in vivo, post-mortem and frozen-thawed. Acta Vet Scand 2019; 61:62. [PMID: 31823831 PMCID: PMC6905104 DOI: 10.1186/s13028-019-0495-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Accepted: 12/02/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The use of cadavers for radiology research methodologies involving subjective image quality evaluation of anatomical criteria is well-documented. The purpose of this method comparison study was to evaluate the image quality of dental and adjacent structures in computed tomography (CT) and high-field (3 T) magnetic resonance (MR) images in cadaveric heads, based on an objective four-point rating scale. Whilst CT is a well-established technique, MR imaging (MRI) is rarely used for equine dental diagnostics. The use of a grading system in this study allowed an objective assessment of CT and MRI advantages in portraying equine cheek teeth. As imaging is commonly performed with cadaveric or frozen and thawed heads for dental research investigations, the second objective was to quantify the impact of the specimens' conditions (in vivo, post-mortem, frozen-thawed) on the image quality in CT and MRI. RESULTS The CT and MR images of nine horses, focused on the maxillary premolar 08s and molar 09s, were acquired post-mortem (Group A). Three observers scored the dental and adjacent tissues. Results showed that MR sequences gave an excellent depiction of endo- and periodontal structures, whereas CT produced high-quality images of the hard tooth and bony tissues. Additional CT and MRI was performed in vivo (Group B) and frozen-thawed (Group C) in three of these nine horses to specify the condition of the best specimens for further research. Assessing the impact of the specimens' conditions on image quality, specific soft tissues of the maxillary 08s and 09s including adjacent structures (pulps, mucosa of the maxillary sinuses, periodontal ligament, soft tissue inside the infraorbital canal) were graded in group B and C and analysed for significant differences within CT and MR modalities in comparison to group A. Results showed that MRI scores in vivo were superior to the post-mortem and frozen-thawed condition. CONCLUSIONS On comparing the imaging performance of CT and MRI, both techniques show a huge potential for application in equine dentistry. Further studies are needed to assess the clinical suitability of MRI. For further research investigations it must be considered, that the best MR image quality is provided in live horses.
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22
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Racine J, O'Brien T, Bladon BM, Cruz AM, Stoffel MH, Haenssgen K, Rodgerson DH, Livesey MA, Koch C. Ceratohyoidectomy in standing sedated horses. Vet Surg 2019; 48:1391-1398. [PMID: 31469435 DOI: 10.1111/vsu.13319] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 06/14/2019] [Accepted: 08/08/2019] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To investigate the feasibility and complications associated with ceratohyoidectomy (CHE) in standing sedated horses unaffected (experimental horses) and standing sedated horses affected (clinical cases) with temporohyoid osteoarthropathy (THO). STUDY DESIGN Case series. ANIMALS Six experimental horses and four clinical cases. METHODS Standing CHE was performed in six experimental horses euthanized 30 minutes (n = 3) and 7 days (n = 3) postoperatively. The four clinical cases were presented because of central facial nerve paralysis (n = 3), vestibular ataxia (n = 3), auricular hemorrhage (n = 2), quidding (n = 1), and oesophageal impaction (n = 1). Evolution was assessed by clinical examination during hospitalization and later by telephone interviews for the clinical cases. RESULTS The procedure was successfully performed in all horses. Experimental horses did not show any short-term postoperative complications. Hemorrhage was experienced intraoperatively in one of the clinical cases and was successfully managed with placement of hemostatic forceps. Vestibular ataxia and other symptoms of THO improved within days, but facial nerve paralysis did not improve until 9 days to 6 months after surgery. Follow-up ranged from 9 to 24 months. All clinical cases returned to performance, and client satisfaction was excellent. CONCLUSION Ceratohyoidectomy was consistently feasible in standing sedated horses. The method did not result in postoperative complications and led to resolution of clinical signs associated with THO. CLINICAL SIGNIFICANCE Standing CHE should be considered in horses affected with THO, especially when horses present with marked vestibular deficits and ataxia, to reduce risks associated with recovery from general anesthesia.
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Affiliation(s)
- Julien Racine
- Department of Equine Surgery, Swiss Institute for Equine Medicine, University of Bern, Bern, Switzerland
| | - Thomas O'Brien
- Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Bruce M Bladon
- Donnington Grove Veterinary Surgery, Oxford Road, Newbury, United Kingdom
| | - Antonio M Cruz
- Department of Equine Surgery, Swiss Institute for Equine Medicine, University of Bern, Bern, Switzerland
| | - Michael H Stoffel
- Department of Veterinary Anatomy, Swiss Institute for Equine Medicine, University of Bern, Bern, Switzerland
| | - Kati Haenssgen
- Department of Veterinary Anatomy, Swiss Institute for Equine Medicine, University of Bern, Bern, Switzerland
| | - Dwayne H Rodgerson
- Davidson Surgical Center, Hagyard Equine Medical Institute, Lexington, Kentucky
| | - Michael A Livesey
- Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Christoph Koch
- Department of Equine Surgery, Swiss Institute for Equine Medicine, University of Bern, Bern, Switzerland
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23
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Bregger MDK, Koch C, Zimmermann R, Sangiorgio D, Schweizer-Gorgas D. Cone-beam computed tomography of the head in standing equids. BMC Vet Res 2019; 15:289. [PMID: 31409395 PMCID: PMC6693248 DOI: 10.1186/s12917-019-2045-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 08/06/2019] [Indexed: 11/22/2022] Open
Abstract
Background Computed tomography in standing horses has revolutionized diagnostic imaging. The O-arm®, a cone beam computed tomography (CBCT) scanner with a gantry opening of 96.5 cm is routinely used for image-guided spine and neurosurgery in humans. The aim of this study is to describe the set-up and first experiences using the O-arm® to achieve CBCT imaging of the head in standing horses. CT imaging of the predefined region of interest (ROI) was tested on 2 cadaveric heads, concentrating on centering issues within the gantry, as well as determining the number of scans needed per ROI. All horses presented with head-related diseases and subjected to a CBCT examination between February 2015 and November 2016 for CBCT were included. Per scan, a limited field of view, i.e. a cylindrical volume of 21 cm in diameter and 16 cm in height was acquired within 13 s. Depending on the dimensions of the ROI, the minimum number of scans could range from one to six, if the entire equine head is to be examined in an adult horse. Results Sixty-eight horses were included, five of which had a follow-up CBCT exam, and two of which were presented twice for two different indications (75 clinical cases). A total number of 449 acquired three-dimensional (3D) scans were recorded for these 75 cases. Two-hundred and forty-two 3D scans (54%) were considered as diagnostic quality. The imaging procedure was generally well tolerated by the sedated, standing equid, and diagnostic studies were performed in 73 out of 75 cases (97.3%). Motion artefacts and inadequate centering of the ROI were the most common reasons for non-diagnostic quality images and repeat scans of the same ROI. Conclusions CBCT is a valuable imaging modality for the equine head. Advantages of the O-arm® compared to a conventional multi-slice helical CT for imaging of the head in standing equids include the rapid image acquisition, the gantry’s mobility in all dimensions, and the free movability of the entire imaging unit. Disadvantages include the considerable sensitivity to motion artefact, increased scatter, low soft tissue contrast and the limited dimensions of the field of view.
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Affiliation(s)
- M D Klopfenstein Bregger
- Swiss Institute of Equine Medicine (ISME), Department of Clinical Veterinary Medicine, Vetsuisse-Faculty University of Bern, and Agroscope, Bern, Switzerland.
| | - C Koch
- Swiss Institute of Equine Medicine (ISME), Department of Clinical Veterinary Medicine, Vetsuisse-Faculty University of Bern, and Agroscope, Bern, Switzerland
| | - R Zimmermann
- Division of Clinical Radiology, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
| | - D Sangiorgio
- Division of Clinical Radiology, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
| | - D Schweizer-Gorgas
- Division of Clinical Radiology, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
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Edwards RA, Hermans H, Veraa S. Morphological variations of the infraorbital canal during CT has limited association with headshaking in horses. Vet Radiol Ultrasound 2019; 60:485-492. [PMID: 31161704 DOI: 10.1111/vru.12773] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 03/01/2019] [Accepted: 04/03/2019] [Indexed: 12/14/2022] Open
Abstract
Headshaking is a common problem in horses. The etiology is unknown but thought to involve sensory input from branches of the trigeminal nerve, some of which are within the infraorbital canal. The objective of this retrospective cross-sectional study was to describe the CT anatomy and variations of the infraorbital canal in horses with local disease processes and normal horses, and to examine associations between those findings and headshaking. Computed tomography scans were reviewed and morphological changes of the infraorbital canal were described. Presence of changes was then tested for association with headshaking prevalence, presence of disease processes in the region of the infraorbital canal, age, and sex. Nonparametric tests were used and a P-value of .05 was considered significant. A total of 218 horses were included, 9% of which had headshaking and 45% had CT lesions in the region of the infraorbital canal. Morphological changes to the bone of the infraorbital canal were found in 121 horses (56%) and included the following: increased mineralization 39 (18%), decreased mineralization 89 (41%), deformed shape 51 (23%), displaced position 43 (20%), and disruption 11 (5%). All changes of the infraorbital canal significantly increased in frequency with the presence of adjacent disease. Increased mineralization and disruption of the infraorbital canal were significantly associated with headshaking in horses with adjacent disease; the latter only reached significance after exclusion of dentally immature horses. No other changes were significantly associated with the presence of headshaking. No association was found between headshaking and the age or sex of the horse.
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Affiliation(s)
- Ralph A Edwards
- Division of Diagnostic Imaging, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Hanneke Hermans
- Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Stefanie Veraa
- Division of Diagnostic Imaging, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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25
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Manso‐Díaz G, Taeymans O, García‐López JM, Weller R. Application and indications of magnetic resonance imaging and computed tomography of the equine head. EQUINE VET EDUC 2019. [DOI: 10.1111/eve.13075] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- G. Manso‐Díaz
- Hospital Clínico Veterinario Complutense Universidad Complutense de Madrid Madrid Spain
- The Royal Veterinary College Hatfield Hertfordshire UK
| | | | - J. M. García‐López
- Department of Clinical Sciences Cummings School of Veterinary Medicine Tufts University North Grafton Massachusetts USA
| | - R. Weller
- The Royal Veterinary College Hatfield Hertfordshire UK
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26
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Frietman SK, van Proosdij ER, Veraa S, de Heer N, Ter Braake F. A minimally invasive partial condylectomy and temporal bone resection for the treatment of a suspected chronic synovial sepsis of the temporomandibular joint in a 3.5-year-old paint horse gelding. Vet Q 2019; 38:118-124. [PMID: 30773124 PMCID: PMC6830993 DOI: 10.1080/01652176.2018.1535216] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Affiliation(s)
- S K Frietman
- a Equine Department , Equine Veterinary Clinic Emmeloord , Espelerlaan 77 , Emmeloord 8302 DC , the Netherlands
| | - E R van Proosdij
- b Equine Department , DAP VUG , Evertsenlaan 18 , Voorthuizen 3781 TB , the Netherlands
| | - S Veraa
- c Division of Diagnostic Imaging , Utrecht University , Yalelaan 108 , Utrecht 3584 CM , the Netherlands
| | - N de Heer
- a Equine Department , Equine Veterinary Clinic Emmeloord , Espelerlaan 77 , Emmeloord 8302 DC , the Netherlands
| | - F Ter Braake
- a Equine Department , Equine Veterinary Clinic Emmeloord , Espelerlaan 77 , Emmeloord 8302 DC , the Netherlands
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27
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Hollis AR, Dixon JJ, Berlato D, Murray R, Weller R. Computed tomographic dimensions of the normal adult equine eye. Vet Ophthalmol 2019; 22:651-659. [PMID: 30716192 DOI: 10.1111/vop.12636] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 11/14/2018] [Accepted: 11/15/2018] [Indexed: 11/30/2022]
Abstract
There are limited data on whether the dimensions of the equine eye and its internal structures change with bodyweight in horses. The aim of this study was to identify whether the size of the equine eye and its individual structures varied in a predictable manner with bodyweight, and to examine the reliability of computed tomography (CT) scans in the measurement of the equine eye. Ninety horses which had undergone CT examination of the head for non-ocular disease were included. All measurements of the eye were performed twice on all eyes by the same operator to quantify intra-operator agreement, and in 10 cases were also performed by a second operator to quantify inter-operator agreement. Agreement was excellent for all but the rostrocaudal measurement of the anterior chamber, which was fair. The following variables correlated significantly with bodyweight: anterior-posterior size of the globe (correlation coefficient: 0.586) and posterior segment (correlation coefficient: 0.554); the latero-medial size of the globe (correlation coefficient: 0.452), anterior chamber (correlation coefficient: 0.504) and posterior segment (correlation coefficient: 0.455); and the orbital fossa diameter (correlation coefficient: 0.219). The lens size and anterior-posterior distance of the anterior chamber did not correlate significantly with bodyweight. These results suggest that overall eye size and the size of the orbital fossa change with the bodyweight of the horse, but lens size remains consistent, and that CT measurements of the internal structures of the eye are repeatable and reproducible. This information aids in interventional procedures for ocular pathology and assessment of normal anatomy.
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Hargreaves L, Dixon JJ. Computed tomographic description of the highly variable imaging features of equine oromaxillary sinus and oronasal fistulae. Vet Radiol Ultrasound 2018; 59:571-576. [PMID: 29733474 DOI: 10.1111/vru.12630] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 02/13/2018] [Accepted: 02/16/2018] [Indexed: 11/30/2022] Open
Abstract
Oronasal and oromaxillary sinus fistulae are well-documented complications following removal or loss of a maxillary cheek tooth. Diagnosis is currently based on a combination of oral examination, videoendoscopy, radiography, and computed tomography (CT). The objective of this retrospective, case series study was to describe the CT characteristics of confirmed oronasal and oromaxillary sinus fistulae in a group of horses. Inclusion criteria were a head CT acquired at the authors' hospital during the period of 2012-2017, a CT diagnosis of oronasal or oromaxillary sinus fistulae, and a confirmed diagnosis based on a method other than CT. Signalment, clinical findings, oral examination findings, presence of a confirmed fistula, and method for confirmation of the diagnosis were recorded. A veterinary radiologist reviewed CT studies for all included horses and recorded characteristics of the fistulae. Seventeen horses were sampled. Fourteen oromaxillary sinus fistulae and three oronasal fistulae were identified. All fistulae appeared as variably sized focal defects in the alveolar bone. Defects frequently contained a linear tract of heterogeneous material interspersed with gas bubbles, considered consistent with food. Computed tomographic attenuation of the material (Hounsfield units, HU) varied widely within and between cases. In 16 of 17 cases, there was evidence of concurrent dental disease in addition to the fistulae. Although the gold standard diagnostic test remains identification of feed material within the sinus or nasal passages, findings from the current study support the use of CT as an adjunctive diagnostic test for assessing the extent of involvement and presurgical planning.
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Affiliation(s)
- Laura Hargreaves
- Rainbow Equine Hospital, Rainbow Lane, Malton, North Yorkshire, UK
| | - Jonathon J Dixon
- Rainbow Equine Hospital, Rainbow Lane, Malton, North Yorkshire, UK
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Nelson BB, Goodrich LR, Barrett MF, Grinstaff MW, Kawcak CE. Use of contrast media in computed tomography and magnetic resonance imaging in horses: Techniques, adverse events and opportunities. Equine Vet J 2017; 49:410-424. [DOI: 10.1111/evj.12689] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 04/04/2017] [Indexed: 12/20/2022]
Affiliation(s)
- B. B. Nelson
- Gail Holmes Equine Orthopaedic Research Center, Department of Clinical Sciences; College of Veterinary Medicine and Biomedical Sciences, Colorado State University; Fort Collins Colorado USA
| | - L. R. Goodrich
- Gail Holmes Equine Orthopaedic Research Center, Department of Clinical Sciences; College of Veterinary Medicine and Biomedical Sciences, Colorado State University; Fort Collins Colorado USA
| | - M. F. Barrett
- Gail Holmes Equine Orthopaedic Research Center, Department of Clinical Sciences; College of Veterinary Medicine and Biomedical Sciences, Colorado State University; Fort Collins Colorado USA
- Department of Environmental and Radiological Health Sciences; Colorado State University; Fort Collins Colorado USA
| | - M. W. Grinstaff
- Departments of Biomedical Engineering, Chemistry, Materials Science & Engineering and Medicine; Boston University; Boston Massachusetts USA
| | - C. E. Kawcak
- Gail Holmes Equine Orthopaedic Research Center, Department of Clinical Sciences; College of Veterinary Medicine and Biomedical Sciences, Colorado State University; Fort Collins Colorado USA
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Affiliation(s)
| | - T Mair
- Equine Veterinary Education
| | - M Spriet
- Veterinary Radiology and Ultrasound
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Dixon J, Lam R, Weller R, Manso-Díaz G, Smith M, Piercy RJ. Clinical application of multidetector computed tomography and magnetic resonance imaging for evaluation of cranial nerves in horses in comparison with high resolution imaging standards. EQUINE VET EDUC 2016. [DOI: 10.1111/eve.12629] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- J. Dixon
- Department of Clinical Sciences and Services; Royal Veterinary College; Hatfield UK
| | - R. Lam
- Department of Clinical Sciences and Services; Royal Veterinary College; Hatfield UK
| | - R. Weller
- Department of Clinical Sciences and Services; Royal Veterinary College; Hatfield UK
| | - G. Manso-Díaz
- Department of Animal Medicine and Surgery; School of Veterinary Medicine; Universidad Complutense de Madrid; Spain
| | - M. Smith
- Department of Clinical Sciences and Services; Royal Veterinary College; Hatfield UK
| | - R. J. Piercy
- Department of Clinical Sciences and Services; Royal Veterinary College; Hatfield UK
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Drew SJ, Meehan L, Reardon RJM, McGorum BC, Dixon PM, Del-Pozo J. Guttural pouch leiomyosarcoma causing nasopharyngeal compression in a pony. EQUINE VET EDUC 2016. [DOI: 10.1111/eve.12607] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- S. J. Drew
- Easter Bush Pathology; The University of Edinburgh; Roslin Midlothian UK
| | - L. Meehan
- Equine Hospital, Royal (Dick) School of Veterinary Studies and Roslin Institute; The University of Edinburgh; Roslin Midlothian UK
| | - R. J. M. Reardon
- Equine Hospital, Royal (Dick) School of Veterinary Studies and Roslin Institute; The University of Edinburgh; Roslin Midlothian UK
| | - B. C. McGorum
- Equine Hospital, Royal (Dick) School of Veterinary Studies and Roslin Institute; The University of Edinburgh; Roslin Midlothian UK
| | - P. M. Dixon
- Equine Hospital, Royal (Dick) School of Veterinary Studies and Roslin Institute; The University of Edinburgh; Roslin Midlothian UK
| | - J. Del-Pozo
- Easter Bush Pathology; The University of Edinburgh; Roslin Midlothian UK
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Dixon J, Smith K, Perkins J, Sherlock C, Mair T, Weller R. COMPUTED TOMOGRAPHIC APPEARANCE OF MELANOMAS IN THE EQUINE HEAD: 13 CASES. Vet Radiol Ultrasound 2016; 57:246-52. [DOI: 10.1111/vru.12345] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 10/29/2015] [Accepted: 11/02/2015] [Indexed: 11/29/2022] Open
Affiliation(s)
- Jonathon Dixon
- Department of Clinical Sciences and Services; The Royal Veterinary College; Hawkshead Lane Hatfield AL9 7TA UK
| | - Ken Smith
- Department of Clinical Sciences and Services; The Royal Veterinary College; Hawkshead Lane Hatfield AL9 7TA UK
| | - Justin Perkins
- Department of Clinical Sciences and Services; The Royal Veterinary College; Hawkshead Lane Hatfield AL9 7TA UK
| | - Ceri Sherlock
- Bell Equine Veterinary Clinic; Butchers Lane Mereworth Kent ME18 5GS UK
| | - Tim Mair
- Bell Equine Veterinary Clinic; Butchers Lane Mereworth Kent ME18 5GS UK
| | - Renate Weller
- Department of Clinical Sciences and Services; The Royal Veterinary College; Hawkshead Lane Hatfield AL9 7TA UK
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Tucker R, Windley ZE, Abernethy AD, Witte TH, Fiske-Jackson AR, Turner S, Smith LJ, Perkins JD. Radiographic, computed tomographic and surgical anatomy of the equine sphenopalatine sinus in normal and diseased horses. Equine Vet J 2015; 48:578-84. [PMID: 26235828 DOI: 10.1111/evj.12492] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 07/22/2015] [Indexed: 11/28/2022]
Abstract
REASONS FOR PERFORMING STUDY Knowledge of imaging anatomy, surgical anatomy and disorders affecting the sphenopalatine sinus are currently lacking. OBJECTIVES To describe the computed tomographic (CT) and surgical anatomy of the sphenopalatine sinus and diagnosis, treatment and outcome in clinical cases with sphenopalatine sinus disease. STUDY DESIGN Cadaver observational study and retrospective case series. METHODS The sphenopalatine sinuses of 10 normal cadaver heads were examined with digital radiography, CT and sinoscopic examination prior to anatomical sectioning. Sphenopalatine sinus anatomy was described and compared between cadaver specimens across the imaging modalities. Medical records (January 2004-2014) of cases diagnosed with sphenopalatine sinus disease were reviewed. RESULTS The anatomy of the sphenopalatine sinus was variable. The borders of the sphenopalatine sinus were not identifiable on plain radiographs, whereas CT provided useful anatomical information. The palatine portion of the sphenopalatine sinus was consistently accessible sinoscopically and the sphenoidal portion was accessible in 6/10 cadaver heads. Fourteen cases of sphenopalatine sinus disease were identified, presenting with one or more clinical signs of exophthalmos, blindness, unilateral epistaxis or unilateral nasal discharge. Diagnoses included neoplasia (7), progressive ethmoidal haematoma (4), sinus cyst (2) and empyema (1). Computed tomography provided diagnostic information but could not differentiate the nature of soft tissue masses. Standing sinoscopic access to the palatine portion of the sphenopalatine sinus was possible for evaluation, biopsy and resection of abnormal soft tissues. Surgical access to the sphenoidal portion was limited. Eight horses were alive at 1 year after diagnosis, with a worse outcome associated with CT evidence of bone loss and a diagnosis of neoplasia. CONCLUSIONS Sphenopalatine sinus disease should be considered a rare cause of the clinical signs described. Knowledge of the anatomical variation of the sphenopalatine sinus is vital for interpreting CT images. A combination of CT and sinoscopy provides the most comprehensive approach for diagnosis and treatment of sphenopalatine sinus disease.
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Affiliation(s)
- R Tucker
- Department of Veterinary Clinical Science and Services, Royal Veterinary College, Hertfordshire, UK
| | - Z E Windley
- Department of Veterinary Clinical Science and Services, Royal Veterinary College, Hertfordshire, UK
| | - A D Abernethy
- Department of Veterinary Clinical Science and Services, Royal Veterinary College, Hertfordshire, UK
| | - T H Witte
- Department of Veterinary Clinical Science and Services, Royal Veterinary College, Hertfordshire, UK
| | - A R Fiske-Jackson
- Department of Veterinary Clinical Science and Services, Royal Veterinary College, Hertfordshire, UK
| | - S Turner
- Chine House Veterinary Hospital, Sileby, Leicestershire, UK
| | - L J Smith
- Department of Veterinary Clinical Science and Services, Royal Veterinary College, Hertfordshire, UK
| | - J D Perkins
- Department of Veterinary Clinical Science and Services, Royal Veterinary College, Hertfordshire, UK
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Dixon J, Weller R. Advanced diagnostic imaging for neoplastic processes in the head. EQUINE VET EDUC 2014. [DOI: 10.1111/eve.12259] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- J. Dixon
- Equine Referral Hospital; Royal Veterinary College; Hatfield Hertfordshire UK
| | - R. Weller
- Equine Referral Hospital; Royal Veterinary College; Hatfield Hertfordshire UK
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