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Hopfgartner T, Brown JA, Adams MN, Werre SR. Comparison of equine paranasal sinus trephination complications and outcome following standing computed tomography, radiography and sinoscopy guided approaches for the treatment of sinusitis. Vet Surg 2024; 53:54-66. [PMID: 37602997 DOI: 10.1111/vsu.14013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 07/07/2023] [Accepted: 07/31/2023] [Indexed: 08/22/2023]
Abstract
OBJECTIVE The recent availability of standing computed tomography (CT) for equine paranasal sinus disease has enhanced diagnosis and enabled more targeted surgery compared to radiography and sinoscopy. To date, there have been no studies which have critically evaluated the benefit of preoperative CT versus radiography and sinoscopy on complications and outcome in horses undergoing sinus trephination. STUDY DESIGN Retrospective study. ANIMALS A total of 229 equids. METHODS The medical records of equids (229) presented for sinusitis treated via trephination that had CT, radiography and/or sinoscopy at time of surgery between 2009 and 2022 were reviewed. Outcome and complications were evaluated for six different pre- and intraoperative imaging modalities. RESULTS The six groups did not differ in demographics or disease category, though equids with less weight (p = .0179) and shorter disease duration (p = .0075) were more likely to have radiography and sinoscopy based surgical planning. Short-term postoperative complications occurred in 30.1% and were higher in groups using preoperative CT imaging (p = .01), with hemorrhage being the most common surgical complication. Following initial trephination surgery, 57.0% (127/223) of cases resolved and there was no difference between the imaging groups. Final resolution after follow-up medical or surgical treatment increased to 94.6% (211/223) and was not different between the imaging groups or between primary or secondary sinusitis. Additional nasal fenestrations to improve sinonasal drainage, maxillary septal bulla fenestrations and trephinations to treat nasal conchal bullae were made in the CT groups. CLINICAL SIGNIFICANCE CT provided additional diagnostic information and enabled different surgical approaches but did not improve resolution in this study population.
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Affiliation(s)
- Teresa Hopfgartner
- Department of Large Animal Clinical Sciences, Marion duPont Scott Equine Medical Center, Virginia - Maryland Regional College of Veterinary Medicine, Leesburg, Virginia, USA
| | - James A Brown
- Department of Large Animal Clinical Sciences, Marion duPont Scott Equine Medical Center, Virginia - Maryland Regional College of Veterinary Medicine, Leesburg, Virginia, USA
- School of Veterinary Medicine, Texas Tech University, Amarillo, Texas, USA
| | - M Norris Adams
- Department of Large Animal Clinical Sciences, Marion duPont Scott Equine Medical Center, Virginia - Maryland Regional College of Veterinary Medicine, Leesburg, Virginia, USA
| | - Stephen R Werre
- Population Health Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, Virginia, USA
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Borowska M, Jasiński T, Gierasimiuk S, Pauk J, Turek B, Górski K, Domino M. Three-Dimensional Segmentation Assisted with Clustering Analysis for Surface and Volume Measurements of Equine Incisor in Multidetector Computed Tomography Data Sets. SENSORS (BASEL, SWITZERLAND) 2023; 23:8940. [PMID: 37960639 PMCID: PMC10650163 DOI: 10.3390/s23218940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 10/22/2023] [Accepted: 10/31/2023] [Indexed: 11/15/2023]
Abstract
Dental diagnostic imaging has progressed towards the use of advanced technologies such as 3D image processing. Since multidetector computed tomography (CT) is widely available in equine clinics, CT-based anatomical 3D models, segmentations, and measurements have become clinically applicable. This study aimed to use a 3D segmentation of CT images and volumetric measurements to investigate differences in the surface area and volume of equine incisors. The 3D Slicer was used to segment single incisors of 50 horses' heads and to extract volumetric features. Axial vertical symmetry, but not horizontal, of the incisors was evidenced. The surface area and volume differed significantly between temporary and permanent incisors, allowing for easy eruption-related clustering of the CT-based 3D images with an accuracy of >0.75. The volumetric features differed partially between center, intermediate, and corner incisors, allowing for moderate location-related clustering with an accuracy of >0.69. The volumetric features of mandibular incisors' equine odontoclastic tooth resorption and hypercementosis (EOTRH) degrees were more than those for maxillary incisors; thus, the accuracy of EOTRH degree-related clustering was >0.72 for the mandibula and >0.33 for the maxilla. The CT-based 3D images of equine incisors can be successfully segmented using the routinely achieved multidetector CT data sets and the proposed data-processing approaches.
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Affiliation(s)
- Marta Borowska
- Institute of Biomedical Engineering, Faculty of Mechanical Engineering, Białystok University of Technology, 15-351 Bialystok, Poland; (M.B.); (S.G.); (J.P.)
| | - Tomasz Jasiński
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland; (T.J.); (B.T.); (K.G.)
| | - Sylwia Gierasimiuk
- Institute of Biomedical Engineering, Faculty of Mechanical Engineering, Białystok University of Technology, 15-351 Bialystok, Poland; (M.B.); (S.G.); (J.P.)
| | - Jolanta Pauk
- Institute of Biomedical Engineering, Faculty of Mechanical Engineering, Białystok University of Technology, 15-351 Bialystok, Poland; (M.B.); (S.G.); (J.P.)
| | - Bernard Turek
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland; (T.J.); (B.T.); (K.G.)
| | - Kamil Górski
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland; (T.J.); (B.T.); (K.G.)
| | - Małgorzata Domino
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland; (T.J.); (B.T.); (K.G.)
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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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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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Jehle MC, Biermann NM, Haltmayer E. Trephination versus Minimally Invasive Transnasal Approaches for the Diagnosis and Treatment of Sinus Disease in Horses. Vet Sci 2022; 9:vetsci9070334. [PMID: 35878351 PMCID: PMC9323710 DOI: 10.3390/vetsci9070334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Revised: 06/20/2022] [Accepted: 06/24/2022] [Indexed: 11/16/2022] Open
Abstract
This retrospective case series aims to highlight the advantages and disadvantages of different treatment options for sinus disease in horses, with a special focus on surgical approaches. The medical records of 25 horses with sinusitis which presented to the equine hospital, Vetmeduni Vienna, between August 2020 and January 2022 were analysed. In 11 cases, conservative treatment by the transnasal endoscopic lavage of the affected sinuses through the sinonasal channel or through a developed, pre-existing sinonasal fistula was performed. In the remaining 14 cases, openings into the sinus for subsequent lavage were surgically created either via classical trephination/bone flaps (8) or by transnasal endoscopically guided minimally invasive approaches (8). In some cases (2), a combination of classical extra-nasal and minimally invasive transnasal approaches was required. The minimally invasive techniques used were comprised of laser surgery (3), electrosurgery (3) and balloon sinoplasty (2). The sinusitis and underlying diseases were successfully treated in all of the horses until hospital discharge. Long-term follow-up could be obtained only from a small number of patients due to the temporal proximity (the study began two years ago) to their initial discharge from the hospital, but they showed the continuous resolution of clinical signs in all cases in which follow up data were available. The results of this case series indicate that if surgical intervention is required, minimally invasive techniques appear to be a promising and potentially cheaper alternative to classical extra-nasal approaches for the treatment of sinus disease in selected cases. In the future, the use of these techniques should be considered more commonly with the broader availability of improved endoscopes and instruments. Additionally, by using small-diameter endoscopes, the need for any surgical intervention might be significantly reduced in many cases.
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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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7
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Stemmet GP, Robert MP, Smit Y. Unilateral, Rostral Maxillary Sinusitis Resulting from Displacement and Retention of an Alveolar Plug in a 4-Year-Old Horse. J Vet Dent 2022; 39:278-283. [DOI: 10.1177/08987564221104206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Sinusitis is a common occurrence in horses and often develops secondary to dental disease. Extraction of cheek teeth in horses is associated with variable degrees of complications and although postoperative displacement and retention of alveolar plugs has been identified as one such potential complication, few cases of resulting sinusitis have been reported. This manuscript describes a four-year-old Thoroughbred mare that was presented for chronic unilateral left-sided mucopurulent nasal discharge after extraction of the left maxillary second molar tooth two months earlier. Radiographic and computed tomographic (CT) examinations revealed a well circumscribed, soft tissue opacity in the left rostral sinus compartment. Intraoral examination revealed feed impacted in the alveolus of the extracted tooth and an oral sinus fistula. Upper airway endoscopy showed thick, purulent material at the nasomaxillary aperture. Sinoscopy showed unexpectedly clean frontal, dorsal conchal and caudal maxillary sinuses. The alveolar dental plug associated with previous exodontia became apparent within the sinus and was removed through the sinoscopy portal. Repeat endoscopies confirmed progressive clearance of the sinusitis during hospitalization. Unilateral nasal discharge returned three months later. An abscess within the sinus had formed. Complete resolution of the sinusitis was achieved after lancing the abscess and further sinus lavage. Sinoscopy through a frontal sinus trephination portal proved useful in diagnosis and treatment. Detailed evaluation of structures allowed for rapid establishment of adequate drainage and communication between all sinus compartments without osteoplastic surgery.
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Affiliation(s)
- Gideon P. Stemmet
- Department of Companion Animal Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa
| | - Mickaël P. Robert
- Centre Hospitalier Vétérinaire Equin de Livet, 1497 Route de Castillon, 14140 Livarot Pays d'Auge, France
| | - Yolandi Smit
- Department of Companion Animal Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa
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8
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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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Gardner A, Lorbach J, Rice H. Heterotopic polydontia as a cause for a cystic lesion in the paranasal sinus of a Thoroughbred filly. EQUINE VET EDUC 2021. [DOI: 10.1111/eve.13452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- A. Gardner
- The Ohio State University Columbus OhioUSA
| | - J. Lorbach
- The Ohio State University Columbus OhioUSA
| | - H. Rice
- Littleton Equine Medical Center Littleton Colorado USA
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10
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Easton‐Jones CA, Marr CM, Peter VG, Foote AK. Vascular air embolisation and expansile sphenopalatine sinus haematoma secondary to a fracture of the rostral skull in a horse. EQUINE VET EDUC 2021. [DOI: 10.1111/eve.13569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
| | - C. M. Marr
- Rossdales Equine Hospital and Diagnostic Centre Exning UK
| | - V. G. Peter
- Rossdales Equine Hospital and Diagnostic Centre Exning UK
| | - A. K. Foote
- Rossdales Equine Hospital and Diagnostic Centre Exning UK
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11
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Smith CE, Cullen MD, Forman IM, Talbot AM, Stack JD. Diffuse osteomyelitis of the fourth metacarpal bone in a horse caused by
Clostridium perfringens. EQUINE VET EDUC 2021. [DOI: 10.1111/eve.13566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- C. E. Smith
- School of Veterinary Science Philip Leverhulme Equine Hospital Neston
| | - M. D. Cullen
- School of Veterinary Science Philip Leverhulme Equine Hospital Neston
| | | | - A. M. Talbot
- School of Veterinary Science Philip Leverhulme Equine Hospital Neston
| | - J. D. Stack
- School of Veterinary Science Philip Leverhulme Equine Hospital Neston
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12
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Pujol R, Tessier C, Manneveau G, De Fourmestraux C. Suspected primary mycotic rhinitis and paranasal sinusitis in seven horses (2013–2019). EQUINE VET EDUC 2021. [DOI: 10.1111/eve.13275] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- R. Pujol
- Department of Surgery Equine Clinic ONIRIS National College of Veterinary Medicine Food Science and Engineering Nantes France
| | - C. Tessier
- Department of Surgery Equine Clinic ONIRIS National College of Veterinary Medicine Food Science and Engineering Nantes France
| | - G. Manneveau
- Department of Surgery Equine Clinic ONIRIS National College of Veterinary Medicine Food Science and Engineering Nantes France
- Clinique Équine de Provence Saint‐Cannat France
| | - C. De Fourmestraux
- Department of Surgery Equine Clinic ONIRIS National College of Veterinary Medicine Food Science and Engineering Nantes France
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13
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Stewart HL, Siewerdsen JH, Nelson BB, Kawcak CE. Use of cone-beam computed tomography for advanced imaging of the equine patient. Equine Vet J 2021; 53:872-885. [PMID: 34053096 DOI: 10.1111/evj.13473] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 04/14/2021] [Accepted: 05/27/2021] [Indexed: 11/28/2022]
Abstract
Access to volumetric imaging modalities, such as magnetic resonance imaging (MRI) and computed tomography (CT), has increased over the past decade and has revolutionised the way clinicians evaluate equine anatomy. More recent advancements have resulted in the development of multiple commercially available cone-beam CT (CBCT) scanners for equine use. CBCT scanners modify the traditional fan-shaped beam of ionising radiation into a three-dimensional pyramidal- or cone-shaped beam of radiation. This modification enables the scanner to acquire sufficient data to create diagnostic images of a region of interest after a single rotation of the gantry. The rapid acquisition of data and divergent X-ray beam causes some artifacts to be more prominent on CBCT images-as well as the unique cone-beam artifact-resulting in decreased contrast resolution. While the use of CT for evaluation of the equine musculoskeletal anatomy is not new, there is a paucity of literature and scientific studies on the capabilities of CBCT for equine imaging. CBCT units do not require a specialised table for imaging and in some cases are portable for imaging in the standing or anaesthetised patient. This review article summarises the basic physics of CT technology, including how CBCT imaging differs, and provides objective information about the strengths and limitations of this modality. Finally, potential future applications and techniques for imaging with CT which will need to be explored in order to fully consider the capabilities of CT imaging in the horse are discussed.
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Affiliation(s)
- Holly L Stewart
- Department of Clinical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Jeffery H Siewerdsen
- The Russel H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Brad B Nelson
- Department of Clinical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Christopher E Kawcak
- Department of Clinical Sciences, Colorado State University, Fort Collins, CO, USA
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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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Rowley KJ, Townsend NB, Chang YMR, Fiske-Jackson AR. A computed tomographic study of endodontic and apical changes in 81 equine cheek teeth with sagittal fractures. Equine Vet J 2021; 54:541-548. [PMID: 34060137 DOI: 10.1111/evj.13475] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 04/06/2021] [Accepted: 05/20/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Sagittal fractures of equine cheek teeth are commonly observed during oral examination. There are few reports on the apical and endodontic pathology associated with such fractures seen during computed tomographic (CT) examination. OBJECTIVES This study aimed to document the prevalence of CT changes indicative of apical disease in equine cheek teeth, which have suffered a sagittal fracture involving the clinical ± reserve crown. STUDY DESIGN This study is a retrospective case series. METHODS CT examinations of equine heads with sagittal fractures of cheek teeth present were reviewed: 81 teeth from 49 horses were identified to have a sagittal cheek tooth fracture. The images were evaluated for apical pathology including gas (in the endodontic system and periapically), widened periodontal space, periapical sclerosis, apical clubbing, cementoma/hypercementosis, lamina dura loss, associated sinusitis and sinus mucosal swelling. An apical infection grading system was created to give each tooth a score. Hounsfield units were used to measure the density of the endodontic, apical and periapical regions. The fracture length ratio was recorded. Statistical analysis was performed using a generalised estimating equation to evaluate predictors of apical infection and associations between clinical signs and CT abnormalities. RESULTS Eighty-seven sagittal fractures (56 buccal, 17 palatal/lingual and 14 midline) from 81 teeth were recorded (74 maxillary and 7 mandibular). Apical infection was diagnosed in 73% (37/51, P = .05) of buccal, 55% (6/11, P = .07) of palatal/lingual, 100% (13/13) of midline, 100% (6/6) of multiple fractures and 96% (23/24, P = .008) of fractures involving infundibula. There was no significant relationship between apical infection and the presence of clinical signs associated with dental pathology (P = .4). There was no significant association between fracture length ratio and apical infection (P = 1.0). Midline sagittal fractures were significantly associated with sinusitis when compared with all other maxillary fractures (odds ratio [OR] 5.92, 95% confidence interval [CI] 1.67-20.83, P = .006). Loss of the lamina dura was not significantly associated with apical infection (P = .5). MAIN LIMITATIONS There is a maxillary cheek tooth bias in the data set and the subjective grading system. CONCLUSIONS A large proportion of fractured cheek teeth have evidence of apical infection on CT examination and therefore warrant treatment.
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Affiliation(s)
| | | | - Yu-Mei R Chang
- Royal Veterinary College, Research Support Office, London, UK
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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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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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Maxillary Incisors of the Horse before and at the Beginning of the Teeth Shedding: Radiographic and CT Study. Animals (Basel) 2020; 10:ani10091618. [PMID: 32927717 PMCID: PMC7552196 DOI: 10.3390/ani10091618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 08/28/2020] [Accepted: 08/31/2020] [Indexed: 11/16/2022] Open
Abstract
To gain insight into the radiographic appearance of maxillary deciduous incisors and dental germs of maxillary permanent incisors in the period prior to teeth shedding, radiographs and computed tomography (CT) of 25 horse skulls, with an estimated age of between 12 and 42 months, were studied. Data regarding morphology and development were obtained. Dental germs of first maxillary permanent incisors were identified radiographically as rounded radiolucent areas at the level of the apical parts of the first deciduous incisors, in skulls with an estimated age of twelve months. The first sign of crown mineralization of these dental germs appeared in skulls supposedly a few months older. Before teeth shedding, the unerupted, mineralized crowns of the first permanent incisor could be identified radiographically relatively caudal to the corresponding first deciduous incisors. The results of the present study indicate that radiographic intraoral images are suitable to identify the grade of development of the dental germs of maxillary permanent incisors. A detailed description of the radiographic appearance of deciduous incisors and dental germs of permanent incisors will help clinicians to expand their knowledge for diagnostic or treatment purposes.
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Jones R. Medial pterygoid myositis in a Thoroughbred gelding – an imaging perspective. EQUINE VET EDUC 2020. [DOI: 10.1111/eve.13077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- R. Jones
- B&W Equine Hospital Berkeley Gloucestershire UK
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Tannahill VJ, Giavitto A, Munroe GA. Medial pterygoid myositis in a Thoroughbred gelding. EQUINE VET EDUC 2020. [DOI: 10.1111/eve.13051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- V. J. Tannahill
- University of Bristol School of Veterinary Sciences Langford, Bristol UK
| | - A. Giavitto
- University of Bristol School of Veterinary Sciences Langford, Bristol UK
| | - G. A. Munroe
- Flanders Veterinary Services Cowrig Cottage Greenlaw, Duns UK
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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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Ostrowska J, Lindström L, Tóth T, Hansson K, Uhlhorn M, Ley CJ. Computed tomography characteristics of equine paranasal sinus cysts. Equine Vet J 2020; 52:538-546. [PMID: 31793020 DOI: 10.1111/evj.13212] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 10/10/2019] [Accepted: 11/23/2019] [Indexed: 11/28/2022]
Abstract
BACKGROUND Computed tomography (CT) is commonly used to investigate equine paranasal sinus disease, however, only limited information is available in the literature about the detailed CT appearance of equine paranasal sinus cysts. OBJECTIVES To investigate if paranasal sinus cysts have specific characteristics in CT images that allow differentiation from other sinus diseases. STUDY DESIGN Retrospective observational study. METHODS Evaluation and comparison of CT studies of eight horses with surgically and/or histopathologically confirmed paranasal sinus cysts and 10 horses with other confirmed paranasal sinus diseases. RESULTS A discrete hyperattenuating wall-like structure was detected in the periphery of the sinus lesion in precontrast acquisition in 7/8 horses with paranasal sinus cysts. A similar wall-like structure was detected in 3/10 horses with other sinus diseases, however, in contrast to horses with paranasal sinus cysts, two of these also had hyperattenuating regions within the contents of the sinus lesion. Bone destruction and formation affecting cancellous and cortical bone and dental disease were frequent in horses with paranasal sinus cysts. No significant difference in attenuation values was found when the fluid/soft tissue attenuation contents of lesions in horses with paranasal sinus cysts (mean 28.9 ± SD 9.2 HU) were compared with other sinus diseases when ethmoid haematomas were excluded (30.4 ± 12.9 HU, P = .8). MAIN LIMITATIONS Low number of cases. CONCLUSIONS Detection of a hyperattenuating cystic wall is a helpful feature for identifying paranasal sinus cysts in CT images of horses. In contrast, measurement of attenuation values of the soft tissue/fluid contents of the sinus lesions was not helpful in identifying paranasal sinus cysts.
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Affiliation(s)
- Justyna Ostrowska
- University Animal Hospital, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Lisa Lindström
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Tamás Tóth
- University Animal Hospital, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Kerstin Hansson
- Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Margareta Uhlhorn
- University Animal Hospital, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Charles J Ley
- Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
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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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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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Poore LA, Le Roux C, Carstens A. Trauma-induced exostosis of multiple suture lines causing partial bilateral nasolacrimal duct obstruction in a 7-year-old Thoroughbred mare. J S Afr Vet Assoc 2019; 90:e1-e7. [PMID: 31588759 PMCID: PMC6783641 DOI: 10.4102/jsava.v90i0.1764] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 07/10/2019] [Accepted: 07/12/2019] [Indexed: 11/18/2022] Open
Abstract
A definitive diagnosis of extensive suture line exostoses affecting the nasofrontal, nasolacrimal, nasomaxillary, frontolacrimal, lacrimozygomatic and lacrimomaxillary suture lines in a 7-year-old Thoroughbred mare with chronic bilateral epiphora and facial deformation was achieved using standing computed tomography (CT) examinations. Positive contrast dacryocystorhinography using CT revealed partial bilateral obstruction of the nasolacrimal ducts. Minimally displaced depression fractures of the right nasal bone, the right maxillary bone and right frontal bone were also demonstrated. The cosmetic appearance of the periosteal reaction associated with the suture line exostosis and epiphora significantly improved within 3 months of diagnosis and treatment.
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Affiliation(s)
- Luke A Poore
- Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria.
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Robert MP, Stemmet GP, Smit Y. A bilateral sinus cyst treated via a bilateral frontonasal bone flap in a standing horse. J S Afr Vet Assoc 2019; 90:e1-e6. [PMID: 31038323 PMCID: PMC6556708 DOI: 10.4102/jsava.v90i0.1729] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 12/10/2018] [Accepted: 01/23/2019] [Indexed: 11/01/2022] Open
Abstract
Bilateral paranasal sinus diseases are rarely reported in horses. Treatment using a bilateral frontonasal bone flap on a standing, regular-sized adult horse has not been described previously. A 13-year-old Thoroughbred gelding was evaluated for bilateral mucopurulent nasal discharge. Radiographic, endoscopic and computed tomographic examinations revealed bilateral sinus pathological changes consistent with an ethmoid haematoma involving the maxillary and frontal sinuses. A bilateral frontonasal bone flap was created under standing sedation and local anaesthesia. A tracheotomy was performed initially to ensure a patent airway during the procedure. Additional analgesia had to be given to transect the dorsal part of the nasal septum while elevating the flap. The sinus masses were removed and communications with the nasal cavities created uneventfully. Small sequestra were removed transendoscopically from the left caudal maxillary sinus 4 weeks after the initial procedure. The horse made a complete recovery with an excellent cosmetic outcome. Histopathology revealed the mass to be a sinus cyst. We concluded that a bilateral sinus bone flap can be used in adult regular-sized horses to access the left and right paranasal sinuses simultaneously. Regional nerve blocks should be performed in order to increase analgesia. A temporary tracheotomy prevents any airway obstruction during the procedure. The post-operative cosmesis is excellent.
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Affiliation(s)
- Mickaël P Robert
- Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort.
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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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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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Tannahill VJ. Best way to assess the sphenopalatine sinus. EQUINE VET EDUC 2018. [DOI: 10.1111/eve.12720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- V. J. Tannahill
- School of Veterinary Sciences; University of Bristol; Langford Bristol UK
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Łopuszyński W, Bulak K, Komsta R, Twardowski P, Kusy R. Thyroid Metastases From Sinonasal Squamous Cell Carcinoma of a Horse—A Case Report and Literature Review. J Equine Vet Sci 2018. [DOI: 10.1016/j.jevs.2018.02.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Fenner MF, Verwilghen D, Townsend N, Simhofer H, Schwarzer J, Zani DD, Bienert-Zeit A. Paranasal sinus cysts in the horse: Complications related to their presence and surgical treatment in 37 cases. Equine Vet J 2018; 51:57-63. [PMID: 29679404 DOI: 10.1111/evj.12959] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 03/31/2018] [Indexed: 11/27/2022]
Abstract
BACKGROUND Paranasal sinus cysts (PSC) are a common cause of equine secondary sinusitis. The outcome and associated complications have not been frequently reported. OBJECTIVES To review the associated clinical signs, associated morbidities and outcomes of horses treated for PSC. STUDY DESIGN Retrospective multicentre case series. METHODS Retrospective analysis of case records and telephone follow up survey. RESULTS Subjects were 37 horses 1-24 years old that were presented with nasal discharge (n = 31), facial swelling (n = 25) and epiphora (n = 19). Radiography and computed tomography allowed identification of the cyst-induced changes including concomitant tissue destruction (n = 31), leading among other things to local nerve damage causing headshaking (n = 6) and unilateral blindness (n = 1). Radiographic changes to adjacent dental apices were present in 10 horses. Horses over 10 years old showed more of the named associated problems. Post-operative complications included surgical site infection (SSI) (n = 11), nasofrontal suture periostitis (n = 6) and sequestration (n = 1) following removal of the PSC via osteotomy. The long-term response to treatment was available for 28 cases with 22 horses (78.6%) fully cured, 4 (14.3%) partially cured and 2 (7.1%) not responding to treatment. In 7 horses (18.9%) there was recurrence of the cyst post-operatively. MAIN LIMITATIONS Due to the study being a multicentre retrospective case series with collection of data over an extended period, there may be inconsistency in data recording and absence of reporting of some findings. CONCLUSIONS Overall, the diagnosis and treatment of sinus cysts is relatively straightforward and carries a good prognosis. In long-standing cases complications secondary to the expansive growth of cysts will dramatically affect the prognosis for full recovery due to pressure-induced changes to facial bones, cheek teeth and nerves. These secondary complications mainly occurring in older horses may be due to a combination of a relatively longer period of affection and the inflexibility of older horses' bones. Cyst recurrence following treatment can occur in up to 19% of cases.
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Affiliation(s)
- M F Fenner
- Large Animal Hospital, University of Copenhagen, Copenhagen, Denmark
| | - D Verwilghen
- Large Animal Hospital, University of Copenhagen, Copenhagen, Denmark.,Equinespecialists EU, Smorum, Denmark
| | - N Townsend
- Philip Leverhulme Equine Hospital, University of Liverpool, Liverpool, UK
| | - H Simhofer
- Clinic for Large Animal Surgery, University of Veterinary Medicine Vienna, Vienna, Austria
| | - J Schwarzer
- Veterinary Clinic Gessertshausen, Faculty of Veterinary Medicine - University of Milan, Milan, Italy
| | - D D Zani
- Polo Universitario Veterinario Di Lodi, Faculty of Veterinary Medicine - University of Milan, Milan, Italy
| | - A Bienert-Zeit
- Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany
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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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Schoppe C, Hellige M, Rohn K, Ohnesorge B, Bienert-Zeit A. Comparison of computed tomography and high-field (3.0 T) magnetic resonance imaging of age-related variances in selected equine maxillary cheek teeth and adjacent tissues. BMC Vet Res 2017; 13:280. [PMID: 28874149 PMCID: PMC5585999 DOI: 10.1186/s12917-017-1200-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 08/24/2017] [Indexed: 11/22/2022] Open
Abstract
Background Modern imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI) have the advantage of producing images without superimposition. Whilst CT is a well-established technique for dental diagnostics, MRI examinations are rarely used for the evaluation of dental diseases in horses. Regarding equine endodontic therapies which are increasingly implemented, MRI could help to portray changes of the periodontal ligament and display gross pulpar anatomy. Knowledge of age-related changes is essential for diagnosis, as cheek teeth and surrounding structures alter with increasing age. The aim of the present study was to highlight the advantages of CT and MRI regarding age-related changes in selected equine cheek teeth and their adjacent structures. Results The CT and MRI appearances of the maxillary 08 s and 09 s and adjacent structures were described by evaluation of post-mortem examinations of nine horses of different ages (Group A: <6 years, B: 6–15 years, C: ≥16 years). Most of the tissues selected were imaged accurately with MRI and CT. Magnetic resonance imaging gives an excellent depiction of soft endo- and periodontal units, and CT of hard dental and bony tissues. Negative correlation between dental age and pulpar sizes was found: 71.3% of the changes in pulp dimensions can be explained by teeth aging. Pulpar sizes ranged from 14.3 to 1.3 mm and were significantly smaller in older horses (p < 0.05). A common pulp chamber was present in 33% of the teeth with a mean dental age of 2.25 years. Ninety-four percent of the 08 and 09 alveoli of all groups were in direct contact with the maxillary sinus. An age-related regression was found (R2 = 0.88) for the distance between alveoli and the infraorbital canal. Conclusions The present study provides information about the dental and periodontal age-related morphology and its visibility using different imaging techniques. These results aid in evaluating diagnostic images and in deciding which is the superior imaging modality for clinical cases.
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Affiliation(s)
- Christin Schoppe
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Buenteweg 9, 30559, Hannover, Germany.
| | - Maren Hellige
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Buenteweg 9, 30559, Hannover, Germany
| | - Karl Rohn
- Institute for Veterinary Biometry and Epidemiology, University of Veterinary Medicine Hannover, Foundation, Buenteweg 2, 30559, Hannover, Germany
| | - Bernhard Ohnesorge
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Buenteweg 9, 30559, Hannover, Germany
| | - Astrid Bienert-Zeit
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Buenteweg 9, 30559, Hannover, Germany
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Hermans H, Veraa S, Wolschrijn CF, van Loon JPAM. Local anaesthetic techniques for the equine head, towards guided techniques and new applications. EQUINE VET EDUC 2017. [DOI: 10.1111/eve.12757] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- H. Hermans
- Department of Equine SciencesFaculty of Veterinary Medicine Utrecht UniversityUtrecht The Netherlands
| | - S. Veraa
- Division of Diagnostic ImagingFaculty of Veterinary Medicine Utrecht UniversityUtrecht The Netherlands
| | - C. F. Wolschrijn
- Department of Pathobiology Faculty of Veterinary Medicine Utrecht University Utrecht The Netherlands
| | - J. P. A. M. van Loon
- Department of Equine SciencesFaculty of Veterinary Medicine Utrecht UniversityUtrecht The Netherlands
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Affiliation(s)
| | - T Mair
- Equine Veterinary Education
| | - M Spriet
- Veterinary Radiology and Ultrasound
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Rohwerder B, Buss A, Boening KJ. Computed tomographic diagnosis: Traumatic lingual process fracture and surgical resection. EQUINE VET EDUC 2016. [DOI: 10.1111/eve.12673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- B. Rohwerder
- Tieraerztliche Gemeinschaftspraxis Dres. Janetzko und Lange; Varrelbusch Germany
| | - A. Buss
- Tieraerztliche Gemeinschaftspraxis Dres. Janetzko und Lange; Varrelbusch Germany
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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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Kaminsky J, Bienert-Zeit A, Hellige M, Rohn K, Ohnesorge B. Comparison of image quality and in vivo appearance of the normal equine nasal cavities and paranasal sinuses in computed tomography and high field (3.0 T) magnetic resonance imaging. BMC Vet Res 2016; 12:13. [PMID: 26786270 PMCID: PMC4717646 DOI: 10.1186/s12917-016-0643-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Accepted: 01/14/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Computed tomography (CT) is a well-established imaging technique in the diagnostics of equine sinunasal disease. High-field magnetic resonance imaging (MRI) is becoming more readily available in equine veterinary medicine. MRI is appreciated for its superior ability to depict soft tissues with high contrast. To compare the established technique of CT in the depiction of the equine nasal cavities, paranasal sinuses and adjoining anatomical structures to 3 Tesla MRI the nasal cavities and paranasal sinuses of 13 horses were examined using CT and 3 Tesla MRI. RESULTS Comparison of CT and MRI images of the paranasal sinuses, nasal cavities and adjoining anatomical structures of 13 healthy horses showed that the inter-rater agreement for the CT examinations was higher than the inter-rater agreement for the MRI examinations. CT images proved to be significantly higher rated for the depiction of cortical bone, while MR images were higher rated for the appearance of soft tissues. For the distinction between different tissues or anatomical structures the MR images were significantly higher rated and especially T2-weighted sequences allowed for a good distinction between delicate structures. None of the MRI sequences produced an exact depiction of the lumen of the nasomaxillary aperture while the CT with a bone window allowed for a satisfying visualization. CONCLUSION The CT is an imaging modality that produces high quality images within a short time when examining equine nasal cavities and paranasal sinuses. The strength of CT lies in the high quality depiction of large and delicate structures with high radiodensity. High field MRI with a field strength of 3 Tesla produces images of high quality that allow for the distinction of delicate soft tissue structures but requires long examination times. The high field strength of 3 Tesla magnetic imaging introduces new possibilities in tomographic soft tissue imaging of the equine head but cannot match up with the CT in terms of visualization of bone and total examination duration. Therefore, clinicians should consider the exact imaging needs in clinical cases to decide whether a single examination or a combination of both imaging techniques may promise the greatest benefit for the patient.
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Affiliation(s)
- Joachim Kaminsky
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Bünteweg 9, Hannover, D-30559, Germany.
| | - Astrid Bienert-Zeit
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Bünteweg 9, Hannover, D-30559, Germany.
| | - Maren Hellige
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Bünteweg 9, Hannover, D-30559, Germany.
| | - Karl Rohn
- Institute for Biometry, Epidemiology and Information Processing, University of Veterinary Medicine Hannover, Foundation, Bünteweg 2, Hannover, D-30559, Germany.
| | - Bernhard Ohnesorge
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Bünteweg 9, Hannover, D-30559, Germany.
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