1
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Santifort K, Bellekom S, Carrera I, Mandigers P. Craniocervical Morphometry in Pomeranians-Part II: Associations with Chiari-like Malformation and Syringomyelia. Animals (Basel) 2024; 14:1859. [PMID: 38997971 DOI: 10.3390/ani14131859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Revised: 06/13/2024] [Accepted: 06/20/2024] [Indexed: 07/14/2024] Open
Abstract
BACKGROUND The aim of Part II of this two-part study is to describe and analyze the association of various aspects and measurements related to the morphometry of the skull and craniocervical region to CM/SM status of Pomeranians, by means of computed tomography (CT) and magnetic resonance imaging (MRI). METHODS Prospectively, Pomeranians were included that underwent both CT and MRI studies of the head and cervicothoracic vertebral column. For those cases where qualitative classifications differed between observers, the experienced observer re-evaluated the studies and decided on a final classification that was used for further analysis. For quantitative measurements, the means of the observers' measurements were used for analysis. RESULTS Among statistically significant differences in measurements, we found that dogs with SM had a significantly shorter clivus length based on both MRI (p = 0.01) and CT measurements (p = 0.01), and a significantly smaller caudal cranial fossa area based on both MRI (p = 0.02) and CT measurements (p = 0.02). CONCLUSIONS Significant morphometrical differences were identified between dogs with or without CM/SM. The findings in this study add to those already described in other breeds and provide further insight into factors that may play a role in the pathogenesis of CM/SM in Pomeranians.
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Affiliation(s)
- Koen Santifort
- IVC Evidensia Referral Hospital Arnhem, 6825 MB Arnhem, The Netherlands
- IVC Evidensia Referral Hospital Hart van Brabant, 5144 AM Waalwijk, The Netherlands
- Expertise Centre of Genetics, Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CS Utrecht, The Netherlands
| | - Sophie Bellekom
- IVC Evidensia Referral Hospital Hart van Brabant, 5144 AM Waalwijk, The Netherlands
| | | | - Paul Mandigers
- IVC Evidensia Referral Hospital Arnhem, 6825 MB Arnhem, The Netherlands
- Expertise Centre of Genetics, Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CS Utrecht, The Netherlands
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2
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Nitzsche B, Schulze S, Boltze J, Schmidt MJ. Reduced cingulate gyrus volume in Cavalier King Charles Spaniels with syringomyelia and neuropathic pain revealed by voxel-based morphometry: a pilot study. Front Neuroanat 2023; 17:1175953. [PMID: 37529422 PMCID: PMC10389659 DOI: 10.3389/fnana.2023.1175953] [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: 02/28/2023] [Accepted: 06/26/2023] [Indexed: 08/03/2023] Open
Abstract
Objective Pathomorphological alterations of the central nervous system in dogs, such as syringomyelia and Chiari-like malformation, can cause cranial and cervical hyperesthesia and neuropathic pain. The long-term activity of the pain network can induce functional alteration and eventually even morphological changes in the pain network. This may happen especially in the prefrontal and cingulate cortex, where atrophy of the gray matter (GM) was observed in humans with chronic pain, irrespective of the nature of the pain syndrome. We tested the hypothesis that Cavalier King Charles Spaniels (CKCS) with Chiari-like malformation and associated syringomyelia (SM) and pain show cerebral morphological differences compared to animals without signs of syringomyelia and pain. Methods Volumetric datasets of 28 different brain structures were analyzed in a retrospective manner, including voxel-based morphometry, using magnetic resonance imaging data obtained from 41 dogs. Results Volumetric analyses revealed a decrease in GM volumes in the cingulate gyrus (CG) in CKCS with SM and chronic pain when normalized to brain volume. This finding was supported by voxel-based morphometry, which showed a cluster of significance within the CG. Conclusion GM atrophy in the CG is associated with chronic pain and thus may serve as an objective readout parameter for the diagnosis or treatment of canine pain syndromes.
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Affiliation(s)
- Björn Nitzsche
- Department of Nuclear Medicine, University Hospital Leipzig, Leipzig, Germany
- Faculty of Veterinary Medicine, Institute of Anatomy, Histology and Embryology, University of Leipzig, Leipzig, Germany
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Neurosurgery, Neuroradiology and Clinical Neurology, Justus-Liebig-University, Giessen, Germany
| | - Sabine Schulze
- Small Animal Clinic, Department of Veterinary Medicine, Free University of Berlin, Berlin, Germany
| | - Johannes Boltze
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Martin J. Schmidt
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Neurosurgery, Neuroradiology and Clinical Neurology, Justus-Liebig-University, Giessen, Germany
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3
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Wolfer N, Wang-Leandro A, Beckmann KM, Richter H, Dennler M. Intracranial Lesion Detection and Artifact Characterization: Comparative Study of Susceptibility and T2 *-Weighted Imaging in Dogs and Cats. Front Vet Sci 2021; 8:779515. [PMID: 34966811 PMCID: PMC8710604 DOI: 10.3389/fvets.2021.779515] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Accepted: 11/10/2021] [Indexed: 12/28/2022] Open
Abstract
Susceptibility-weighted imaging (SWI), an MRI sequence for the detection of hemorrhage, allows differentiation of paramagnetic and diamagnetic substances based on tissue magnetic susceptibility differences. The three aims of this retrospective study included a comparison of the number of areas of signal void (ASV) between SWI and T2*-weighted imaging (T2*WI), differentiation of hemorrhage and calcification, and investigation of image deterioration by artifacts. Two hundred twelve brain MRIs, 160 dogs and 52 cats, were included. The sequences were randomized and evaluated for presence/absence and numbers of ASV and extent of artifacts causing image deterioration by a single, blinded observer. In cases with a CT scan differentiation of paramagnetic (hemorrhagic) and diamagnetic (calcification) lesions was made, SWI was performed to test correct assignment using the Hounsfield Units. Non-parametric tests were performed to compare both sequences regarding detection of ASV and the effect of artifacts on image quality. The presence of ASV was found in 37 SWI sequences and 34 T2*WI sequences with a significant increase in ASV only in dogs >5 and ≤ 15 kg in SWI. The remaining weight categories showed no significance. CT examination was available in 11 cases in which 81 ASV were found. With the use of phase images, 77 were classified as paramagnetic and none as diamagnetic. A classification was not possible in four cases. At the level of the frontal sinus, significantly more severe artifacts occurred in cats and dogs (dogs, p < 0.001; cats, p = 0.001) in SWI. The frontal sinus artifact was significantly less severe in brachycephalic than non-brachycephalic dogs in both sequences (SWI, p < 0.001; T2*WI, p < 0.001). In conclusion, with the advantages of better detection of ASV in SWI compared with T2*WI and the opportunity to differentiate between paramagnetic and diamagnetic origin in most cases, SWI is generally recommended for dogs. Frontal sinus conformation appears to be a limiting factor in image interpretation.
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Affiliation(s)
- Nadja Wolfer
- Clinic for Diagnostic Imaging, Department of Clinical Diagnostics and Services, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Adriano Wang-Leandro
- Clinic for Diagnostic Imaging, Department of Clinical Diagnostics and Services, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Katrin M Beckmann
- Section of Neurology and Neurosurgery, Small Animal Clinic, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Henning Richter
- Clinic for Diagnostic Imaging, Department of Clinical Diagnostics and Services, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Matthias Dennler
- Clinic for Diagnostic Imaging, Department of Clinical Diagnostics and Services, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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4
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Geiger M, Schoenebeck JJ, Schneider RA, Schmidt MJ, Fischer MS, Sánchez-Villagra MR. Exceptional Changes in Skeletal Anatomy under Domestication: The Case of Brachycephaly. Integr Org Biol 2021; 3:obab023. [PMID: 34409262 PMCID: PMC8366567 DOI: 10.1093/iob/obab023] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 05/06/2021] [Accepted: 07/08/2021] [Indexed: 01/17/2023] Open
Abstract
"Brachycephaly" is generally considered a phenotype in which the facial part of the head is pronouncedly shortened. While brachycephaly is characteristic for some domestic varieties and breeds (e.g., Bulldog, Persian cat, Niata cattle, Anglo-Nubian goat, Middle White pig), this phenotype can also be considered pathological. Despite the superficially similar appearance of "brachycephaly" in such varieties and breeds, closer examination reveals that "brachycephaly" includes a variety of different cranial modifications with likely different genetic and developmental underpinnings and related with specific breed histories. We review the various definitions and characteristics associated with brachycephaly in different domesticated species. We discern different types of brachycephaly ("bulldog-type," "katantognathic," and "allometric" brachycephaly) and discuss morphological conditions related to brachycephaly, including diseases (e.g., brachycephalic airway obstructive syndrome). Further, we examine the complex underlying genetic and developmental processes and the culturally and developmentally related reasons why brachycephalic varieties may or may not be prevalent in certain domesticated species. Knowledge on patterns and mechanisms associated with brachycephaly is relevant for domestication research, veterinary and human medicine, as well as evolutionary biology, and highlights the profound influence of artificial selection by humans on animal morphology, evolution, and welfare.
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Affiliation(s)
- M Geiger
- Paleontological Institute and Museum, University of Zurich,
Karl-Schmid-Str. 4, 8006 Zurich, Switzerland
| | - J J Schoenebeck
- Roslin Institute and Royal (Dick) School of Veterinary Studies, University
of Edinburgh, Easter Bush Campus, Midlothian EH25
9RG, UK
| | - R A Schneider
- Department of Orthopaedic Surgery, University of California at San
Francisco, 513 Parnassus Avenue, S-1164, San Francisco, CA
94143-0514, USA
| | - M J Schmidt
- Clinic for Small Animals—Neurosurgery, Neuroradiology and Clinical
Neurology, Justus Liebig University Giessen, Frankfurter Str.
114, 35392 Giessen, Germany
| | - M S Fischer
- Institute of Zoology and Evolutionary Research, Friedrich-Schiller
University Jena, Erbertstr. 1, 07743 Jena,
Germany
| | - M R Sánchez-Villagra
- Paleontological Institute and Museum, University of Zurich,
Karl-Schmid-Str. 4, 8006 Zurich, Switzerland
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5
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Saganuwan SA. Modified formulas for calculation of encephalization: quotient in dogs. BMC Res Notes 2021; 14:223. [PMID: 34082832 PMCID: PMC8176606 DOI: 10.1186/s13104-021-05638-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 05/26/2021] [Indexed: 01/14/2023] Open
Abstract
OBJECTIVE Dogs are a breed of animals that play important roles in security service, companionship, hunting, guard, work and models of research for application in humans. Intelligence is the key factor to success in life, most especially for dogs that are used for security purposes at the airports, seaports, public places, houses, schools and farms. However, it has been reported that there is correlation between intelligence, body weight, height and craniometry in human. In view of this, literatures were searched on body weight, height and body surface areas of ten dogs with intent to determining their comparative level of intelligence using encephalization quotient. RESULTS Findings revealed that dogs have relationship of brain allometry with human as proven by encephalization quotient [Formula: see text] and Brain Mass (E) = kpβ, where p is the body weight; k = 0.14 and β = 0.528, respectively. Saganuwa's formula yielded better results as compared with the other formulas. Dogs with body surface area (BSA), weight and height similar to that of human are the most intelligent. Doberman pinscher is the most intelligent followed by German shepherd, Labrador retriever, Golden retriever, respectively.
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Affiliation(s)
- Saganuwan Alhaji Saganuwan
- Department of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Federal University of Agriculture, Benue State, P.M.B. 2373, Makurdi, Nigeria.
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6
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Watson F, Coppi AA, Volk HA, Packer RMA, Tauro A, Rusbridge C. Comparison of volume of the forebrain, subarachnoid space and lateral ventricles between dogs with idiopathic epilepsy and controls using a stereological approach: Cavalieri's principle. Canine Med Genet 2021; 8:3. [PMID: 33691781 PMCID: PMC7944915 DOI: 10.1186/s40575-021-00101-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 02/25/2021] [Indexed: 11/18/2022] Open
Abstract
Background Canine idiopathic epilepsy (IE) is the most common chronic neurological brain disease in dogs, yet it can only be diagnosed by exclusion of all other potential causes. In people, epilepsy has been associated with a reduction in brain volume. The objective was to estimate the volume of the forebrain (FB), subarachnoid space (SAS) and lateral ventricles (LV) in dogs with IE compared to controls using Cavalieri’s principle. MRI scans of case and control dogs were identified from two neurology referral hospital databases. Eight breeds with increased odds of having IE were included: Golden Retriever, Labrador Retriever, Cocker Spaniel, Border terrier, German Shepherd dog, Parson Jack Russell terrier, Boxer, and Border Collie. Five dogs of each breed with IE and up to five controls were systematically and uniformly randomly sampled (SURS). The volume of the FB, SAS and LV were estimated from MRI scans by one blinded observer using Cavalieri’s principle. Results One hundred-two dogs were identified; 56 were diagnosed with IE and 46 were controls. There was no statistically significant difference in FB, SAS and LV volume between dogs with IE and controls. Dogs with a history of status epilepticus had significantly larger FB than those without (p = 0.05). There was a border-line trend for LV volume to increase with increasing length of seizure history in the IE group (p = 0.055). Conclusion The volumes of the FB, SAS and LV are not different between dogs with IE and controls, so IE remains a diagnosis of exclusion with no specific neuroanatomical biomarkers identified. This is the first time FB and SAS volume has been compared in dogs with IE. Unfortunately, we have shown that the results reporting significantly larger FBs in dogs with status epilepticus and LV volume increase with length of seizure history were likely confounded by breed and should be interpreted cautiously. Whilst these associations are interesting and clinically relevant, further investigation with breed-specific or larger, breed-diverse populations are required to permit strong conclusions. The Cavalieri principle provided an effective estimation of FB, SAS and LV volumes on MRI, but may be too time-intensive for use in clinical practice.
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Affiliation(s)
- Fraje Watson
- Royal Veterinary College, Hawkshead Lane, Hertfordshire, Hatfield, AL9 7TA, UK. .,Present Address: University College London, Division of Surgery & Interventional Science, Aspire CREATe, Royal National Orthopaedic Hospital, Brockley Hill, Stanmore, Middlesex, HA7 4LP, UK.
| | - A Augusto Coppi
- School of Animal, Rural and Environmental Sciences, Nottingham Trent University, Nottingham, NG25 0QF, UK
| | - Holger A Volk
- Royal Veterinary College, Hawkshead Lane, Hertfordshire, Hatfield, AL9 7TA, UK.,Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Bünteweg, 30559, Hanover, Germany
| | - Rowena M A Packer
- Royal Veterinary College, Hawkshead Lane, Hertfordshire, Hatfield, AL9 7TA, UK
| | - Anna Tauro
- Chestergates Veterinary Specialists, Telford Court, Units E and F, Gates Lane, Chester, CH1 6LT, UK
| | - Clare Rusbridge
- Present Address: University College London, Division of Surgery & Interventional Science, Aspire CREATe, Royal National Orthopaedic Hospital, Brockley Hill, Stanmore, Middlesex, HA7 4LP, UK.,School of Veterinary Medicine, Faculty of Healthy & Medical Sciences, University of Surrey, Main Academic Building (VSM), Daphne Jackson Road, Guildford, Surrey, GU2 7AL, UK
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7
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Minato S, Cherubini GB, Della Santa D, Salvadori S, Baroni M. Incidence and type of brain herniation associated with intracranial meningioma in dogs and cats. J Vet Med Sci 2020; 83:267-273. [PMID: 33342961 PMCID: PMC7972881 DOI: 10.1292/jvms.20-0111] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The incidence of brain herniation (BH) in association with intracranial meningioma (ICM)
in dogs and cats is poorly described. The aim of this study was to evaluate the rate and
type of brain herniations in client-owned dogs and cats with ICMs and to determine the
meningioma volume (MV) relative to cranial cavity volume (CCV). A retrospective magnetic
resonance imaging (MRI) analysis study of 24 cats and 45 dogs with ICMs was conducted to
ascertain the presence and characteristics of BH. MV and CCV were measured and their ratio
was calculated for each animal. Correlations of MV/CCV with independent variables were
analyzed. BH was encountered in 24/24 cats (100%) and 30/45 dogs (66.7%) with ICMs. In
cats, the most frequent presentation was foramenal herniation (FMH; 23/24, 95.8%),
followed by caudotentorial (CTH; 21/24, 87.5%) and subfalcine (SH; 18/24, 75.0%)
herniation. In dogs, the most frequent presentation was SH (28/45; 62.2%), followed by CTH
(9/45; 20%) and FMH (2/45; 4.4%). Relative to dogs, cats with ICM had greater incidences
of FMH (P<0.001) and CTH (P<0.001). Mean MV/CCV
ratio was higher in cats (0.098) than in dogs (0.038; P<0.001). The
most common clinical sign of ICM was altered behavior in cats (43%,
P<0.01) and seizures in dogs (74.4%, P<0.001). In
conclusion, cats were found to be more likely than dogs to present FMH and CTH, with a
proportionally greater neoplasia volume.
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Affiliation(s)
- Simone Minato
- Valdinievole Veterinary Clinic, Via C. Nigra 123, 51015, Monsummano Terme, PT, Italy
| | - Giunio B Cherubini
- Dick White Referrals, Station Farm, London Road, Six Mile Bottom, Cambridgeshire CB8 0UH, UK
| | | | - Stefano Salvadori
- Institute of Clinical Physiology, National Research Council, Via G. Moruzzi 1, 56124, Pisa, PI, Italy
| | - Massimo Baroni
- Valdinievole Veterinary Clinic, Via C. Nigra 123, 51015, Monsummano Terme, PT, Italy
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8
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Giannasi S, Kani Y, Hsu F, Rossmeisl JH. Comparison of direct measurement of intracranial pressures and presumptive clinical and magnetic resonance imaging indicators of intracranial hypertension in dogs with brain tumors. J Vet Intern Med 2020; 34:1514-1523. [PMID: 32415794 PMCID: PMC7379039 DOI: 10.1111/jvim.15802] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 04/14/2020] [Accepted: 05/01/2020] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Intracranial hypertension (ICH) is often presumptively diagnosed based on clinical or imaging findings. Clinical or imaging surrogates of ICH are not usually validated with reference standard direct intracranial pressure (dICP) recordings. HYPOTHESES Dogs with brain magnetic resonance imaging (MRI) or clinical features of presumed ICH would have higher dICP than dogs lacking those features. ANIMALS Twenty dogs with gliomas and 3 normal controls. METHODS Prospective, convenience study. Dogs were presumptively categorized with normal ICP or ICH from scores generated from described clinical and brain MRI indicators of ICH. dICP was recorded in anesthetized dogs using an intraparenchymal microsensor and compared between groups. RESULTS dICP was not different between control (10.4 ± 2.1 mm Hg) and dogs with glioma (15.6 ± 8.3 mm Hg), or between dogs in clinically predicted ICP groups. Compared with dogs with MRI-predicted normal ICP, MRI-predicted ICH dogs had higher dICP (10.3 ± 4.1 versus 19.2 ± 7.9 mm Hg, P = .004), larger tumors (1.45 ± 1.2 versus 5.71 ± 3.03 cm3 , P = .0004), larger optic nerve sheath diameters, and 14/14 (100%) displayed structural anatomical shifts on MRI. At a dICP threshold of 15 mm Hg, the sensitivity of MRI for predicting ICH was 90% and the specificity 69%. CONCLUSIONS AND CLINICAL RELEVANCE dICP measurements are feasible in dogs with brain tumors. MRI features including brain herniations, mass effect, and optic nerve size aid in the identification of dogs with ICH. Clinical estimation of ICP did not discriminate between dogs with and without ICH.
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Affiliation(s)
- Savannah Giannasi
- Veterinary and Comparative Neuro‐Oncology LaboratoryVirginia‐Maryland College of Veterinary Medicine, Virginia TechBlacksburgVirginiaUSA
| | - Yukitaka Kani
- Veterinary and Comparative Neuro‐Oncology LaboratoryVirginia‐Maryland College of Veterinary Medicine, Virginia TechBlacksburgVirginiaUSA
| | - Fang‐Chi Hsu
- Department of Biostatistics and Data Science, Comprehensive Cancer Center and Brain Tumor Center of ExcellenceWake Forest School of MedicineWinston‐SalemNorth CarolinaUSA
| | - John H. Rossmeisl
- Veterinary and Comparative Neuro‐Oncology LaboratoryVirginia‐Maryland College of Veterinary Medicine, Virginia TechBlacksburgVirginiaUSA
- Department of Cancer Biology, Comprehensive Cancer Center and Brain Tumor Center of ExcellenceWake Forest School of MedicineWinston‐SalemNorth CarolinaUSA
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9
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Johnson PJ, Luh WM, Rivard BC, Graham KL, White A, FitzMaurice M, Loftus JP, Barry EF. Stereotactic Cortical Atlas of the Domestic Canine Brain. Sci Rep 2020; 10:4781. [PMID: 32179861 PMCID: PMC7076022 DOI: 10.1038/s41598-020-61665-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 02/27/2020] [Indexed: 11/16/2022] Open
Abstract
The domestic canine (canis familiaris) is a growing novel model for human neuroscientific research. Unlike rodents and primates, they demonstrate unique convergent sociocognitive skills with humans, are highly trainable and able to undergo non-invasive experimental procedures without restraint, including fMRI. In addition, the gyrencephalic structure of the canine brain is more similar to that of human than rodent models. The increasing use of dogs for non-invasive neuroscience studies has generating a need for a standard canine cortical atlas that provides common spatial referencing and cortical segmentation for advanced neuroimaging data processing and analysis. In this manuscript we create and make available a detailed MRI-based cortical atlas for the canine brain. This atlas includes a population template generated from 30 neurologically and clinically normal non-brachycephalic dogs, tissue segmentation maps and a cortical atlas generated from Jerzy Kreiner's myeloarchitectonic-based histology atlas. The provided cortical parcellation includes 234 priors from frontal, sensorimotor, parietal, temporal, occipital, cingular and subcortical regions. The atlas was validated using an additional canine cohort with variable cranial conformations. This comprehensive cortical atlas provides a reference standard for canine brain research and will improve and standardize processing and data analysis and interpretation in functional and structural MRI research.
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Affiliation(s)
- Philippa J Johnson
- Cornell College of Veterinary Medicine, Department of Clinical Sciences, Cornell University, Ithaca, NY, USA.
| | - Wen-Ming Luh
- National Institute of Aging, National Institutes of Health, Baltimore, MD, USA
| | - Benjamin C Rivard
- Cornell College of Veterinary Medicine, Department of Clinical Sciences, Cornell University, Ithaca, NY, USA
| | - Kathleen L Graham
- Clinical Ophthalmology and Eye Health, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
| | - Andrew White
- Clinical Ophthalmology and Eye Health, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
| | - Marnie FitzMaurice
- Cornell College of Veterinary Medicine, Department of Biomedical Sciences, Cornell University, Ithaca, NY, USA
| | - John P Loftus
- Cornell College of Veterinary Medicine, Department of Clinical Sciences, Cornell University, Ithaca, NY, USA
| | - Erica F Barry
- Cornell College of Veterinary Medicine, Department of Clinical Sciences, Cornell University, Ithaca, NY, USA
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10
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Chen Y, Quddusi A, Harrison KA, Ryan PE, Cook DJ. Selection of preclinical models to evaluate intranasal brain cooling for acute ischemic stroke. Brain Circ 2019; 5:160-168. [PMID: 31950091 PMCID: PMC6950506 DOI: 10.4103/bc.bc_20_19] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 10/28/2019] [Indexed: 01/12/2023] Open
Abstract
Stroke accounts for a large proportion of global mortality and morbidity. Selective hypothermia, via intranasal cooling devices, is a promising intervention in acute ischemic stroke. However, prior to large clinical trials, preclinical studies in large animal models of ischemic stroke are needed to assess the efficacy, safety, and feasibility of intranasal cooling for selective hypothermia as a neuroprotective strategy. Here, we review the available scientific literature for evidence supporting selective hypothermia and make recommendations of a preclinical, large, animal-based, ischemic stroke model that has the greatest potential for evaluating intranasal cooling for selective hypothermia and neuroprotection. We conclude that among large animal models of focal ischemic stroke including pigs, sheep, dogs, and nonhuman primates (NHPs), cynomolgus macaques have nasal anatomy, nasal vasculature, neuroanatomy, and cerebrovasculature that are most similar to those of humans. Moreover, middle cerebral artery stroke in cynomolgus macaques produces functional and behavioral deficits that are quantifiable to a greater degree of precision and detail than those that can be revealed through available assessments for other large animals. These NHPs are also amenable to extensive neuroimaging studies as a means of monitoring stroke evolution and evaluating infarct size. Hence, we suggest that cynomolgus macaques are best suited to assess the safety and efficacy of intranasal selective hypothermia through an evaluation of hyperacute diffusion-weighted imaging and subsequent investigation of chronic functional recovery, prior to randomized clinical trials in humans.
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Affiliation(s)
- Yining Chen
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | - Ayesha Quddusi
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | | | - Paige E Ryan
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | - Douglas J Cook
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada.,Department of Surgery, Division of Neurosurgery, Kingston General Hospital, Kingston, ON, Canada
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11
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Kolecka M, Farke D, Failling K, Kramer M, Schmidt MJ. Intraoperative measurement of intraventricular pressure in dogs with communicating internal hydrocephalus. PLoS One 2019; 14:e0222725. [PMID: 31560704 PMCID: PMC6764652 DOI: 10.1371/journal.pone.0222725] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 09/05/2019] [Indexed: 12/14/2022] Open
Abstract
Collapse of the lateral cerebral ventricles after ventriculo-peritoneal drainage is a fatal complication in dogs with internal hydrocephalus. It occurs due to excessive outflow of cerebrospinal fluid into the peritoneal cavity (overshunting). In most shunt systems, one-way valves with different pressure settings regulate flow into the distal catheter to avoid overshunting. The rationale for the choice of an appropriate opening pressure is a setting at the upper limit of normal intracranial pressure in dogs. However, physiological intraventricular pressure in normal dogs vary between 5 and 12 mm Hg. Furthermore, we hypothesise that intraventricular pressure in hydrocephalic dogs might differ from pressure in normal dogs and we also consider that normotensive hydrocephalus exists in dogs, as in humans. In order to evaluate intraventricular pressure in hydrocephalic dogs, twenty-three client owned dogs with newly diagnosed communicating internal hydrocephalus were examined before implantation of a ventriculo-peritoneal shunt using a single use piezo-resistive strain-gauge sensor (MicroSensor ICP probe). Ventricular volume and brain volume were measured before surgery, based on magnetic resonance images. Total ventricular volume was calculated and expressed in relation to the total volume of the brain, including the cerebrum, cerebellum, and brainstem (ventricle-brain index). Multiple logistic regression analysis was performed to assess the influence of the covariates "age", "gender", "duration of clinical signs", "body weight", and "ventricle-brain index" on intraventricular pressure. The mean cerebrospinal fluid pressure in the hydrocephalic dogs was 8.8 mm Hg (standard deviation 4.22), ranging from 3-18 mm Hg. The covariates "age", (P = 0.782), "gender" (P = 0.162), "body weight", (P = 0.065), or ventricle-brain index (P = 0.27)" were not correlated with intraventricular pressure. The duration of clinical signs before surgery, however, was correlated with intraventricular pressure (P< 0.0001). Dogs with internal hydrocephalus do not necessarily have increased intraventricular pressure. Normotensive communicating hydrocephalus exists in dogs.
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Affiliation(s)
- Malgorzata Kolecka
- Department of Veterinary Clinical Sciences, Small Animal Clinic – Neurosurgery, Neuroradiology and Clinical Neurology, Justus-Liebig-University, Giessen, Germany
| | - Daniela Farke
- Department of Veterinary Clinical Sciences, Small Animal Clinic – Neurosurgery, Neuroradiology and Clinical Neurology, Justus-Liebig-University, Giessen, Germany
| | - Klaus Failling
- Unit for Biomathematics and Data Processing, Faculty of Veterinary Medicine, Justus Liebig-University-Giessen, Giessen, Germany
| | - Martin Kramer
- Department of Veterinary Clinical Sciences, Small Animal Clinic – Neurosurgery, Neuroradiology and Clinical Neurology, Justus-Liebig-University, Giessen, Germany
| | - Martin J. Schmidt
- Department of Veterinary Clinical Sciences, Small Animal Clinic – Neurosurgery, Neuroradiology and Clinical Neurology, Justus-Liebig-University, Giessen, Germany
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12
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Network analysis of canine brain morphometry links tumour risk to oestrogen deficiency and accelerated brain ageing. Sci Rep 2019; 9:12506. [PMID: 31467332 PMCID: PMC6715702 DOI: 10.1038/s41598-019-48446-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 08/02/2019] [Indexed: 12/24/2022] Open
Abstract
Structural ‘brain age’ is a valuable but complex biomarker for several brain disorders. The dog is an unrivalled comparator for neurological disease modeling, however canine brain morphometric diversity creates computational and statistical challenges. Using a data-driven approach, we explored complex interactions between patient metadata, brain morphometry, and neurological disease. Twenty-four morphometric parameters measured from 286 canine brain magnetic resonance imaging scans were combined with clinical parameters to generate 9,438 data points. Network analysis was used to cluster patients according to their brain morphometry profiles. An ‘aged-brain’ profile, defined by a small brain width and volume combined with ventriculomegaly, was revealed in the Boxer breed. Key features of this profile were paralleled in neutered female dogs which, relative to un-neutered females, had an 11-fold greater risk of developing brain tumours. Boxer dog and geriatric dog groups were both enriched for brain tumour diagnoses, despite a lack of geriatric Boxers within the cohort. Our findings suggest that advanced brain ageing enhances brain tumour risk in dogs and may be influenced by oestrogen deficiency—a risk factor for dementia and brain tumours in humans. Morphometric features of brain ageing in dogs, like humans, might better predict neurological disease risk than patient chronological age.
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13
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Montgomery SH. Are brain weights estimated from scaling relationships suitable for comparative studies of animal cognition? Anim Cogn 2019; 22:1191-1195. [DOI: 10.1007/s10071-019-01300-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 07/24/2019] [Accepted: 08/08/2019] [Indexed: 11/30/2022]
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14
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Häußler TC, von Pückler KH, Thiel C, Enderlein S, Failing K, Ondreka N, Kramer M, Schmidt MJ. Measurement of the normal feline pituitary gland in brachycephalic and mesocephalic cats. J Feline Med Surg 2018; 20:578-586. [PMID: 28809124 PMCID: PMC11104064 DOI: 10.1177/1098612x17723774] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objectives The purpose of this study was to determine differences in normal feline pituitary dimensions in brachycephalic and mesocephalic cats as a basis for establishing cryohypophysectomy in cats. Methods Measurements were performed on sagittal T2-weighted and transverse post-gadolinium T1-weighted or T1 3D fast field echo-weighted MRI images. A total of 32 brachycephalic and 27 mesocephalic cats were examined. Inter-observer reproducibility was assessed by t-test and Bland-Altman analysis. Results The cats were 0.6-15.9 years of age with a body weight range of 1.84-6.60 kg. For brachycephalic cats, the mean pituitary gland sagittal height was 2.15 ± 0.15 mm, pituitary gland transverse height was 2.42 ± 0.21 mm, pituitary gland transverse width was 4.44 ± 0.27 mm and pituitary gland sagittal length was 3.14 ± 0.30 mm. In mesocephalic cats, the pituitary gland dimensions were 2.94 ± 0.16 mm, 3.09 ± 0.26 mm, 4.73 ± 0.31 mm and 4.88 ± 0.30 mm for pituitary gland sagittal height, transverse height, transverse width and sagittal length, respectively. There was a highly significant correlation between brachycephalic and mesocephalic cats and pituitary gland height and length ( P <0.0001), respectively. Sex also had an effect on pituitary gland measurements. Neutering status had no significant effect on hypophyseal measurements. Age had a significant influence on pituitary gland height, width and length in the brachycephalic population. Inter-observer reproducibility was good to excellent. Conclusions and relevance The different pituitary measurements in brachycephalic and mesocephalic cats has to be considered if surgery comes into question. There are ranges in pituitary gland sizes, even among the mesocephalic cat population. Thus, exact measuring of the pituitary gland is crucial before any surgical intervention.
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Affiliation(s)
- Thomas Christian Häußler
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Justus Liebig University, Giessen, Germany
| | - Kerstin Heike von Pückler
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Justus Liebig University, Giessen, Germany
| | - Cetina Thiel
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Justus Liebig University, Giessen, Germany
| | - Sylke Enderlein
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Justus Liebig University, Giessen, Germany
| | - Klaus Failing
- Unit for Biomathematics and Data Processing, Faculty of Veterinary Medicine, Justus Liebig University, Giessen, Germany
| | - Nele Ondreka
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Justus Liebig University, Giessen, Germany
| | - Martin Kramer
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Justus Liebig University, Giessen, Germany
| | - Martin Jürgen Schmidt
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Justus Liebig University, Giessen, Germany
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15
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Sokołowski W, Czubaj N, Skibniewski M, Barszcz K, Kupczyńska M, Kinda W, Kiełbowicz Z. Rostral cranial fossa as a site for cerebrospinal fluid drainage - volumetric studies in dog breeds of different size and morphotype. BMC Vet Res 2018; 14:162. [PMID: 29776403 PMCID: PMC5960198 DOI: 10.1186/s12917-018-1483-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 05/02/2018] [Indexed: 11/16/2022] Open
Abstract
Background Hydrocephalus is a multifactorial condition, whose aetiology is not fully understood. Congenital hydrocephalus frequently occurs in small and brachycephalic dog breeds. Although it is widely accepted that the cribriform plate located in the rostral cranial fossa (RCF) is a site of cerebrospinal fluid (CSF) drainage, the RCF has not been studied extensively. Literature reports indicate that a decreased caudal cranial fossa (CCF) volume in the course of the Chiari-like malformation may obstruct CSF circulation. We hypothesised that morphological diversity among different breeds in the volume of the RCF may affect CSF circulation. The aim of the study was to carry out a volumetric analysis of the RCF and the cranial cavity and to determine the ratio between them in dog breeds of different size and morphotype. We performed computed tomography (CT) morphometric analysis of the RCF compartment by obtaining volume measurements from the transverse and reformatted sagittal and dorsal planes. Results The rostral cranial fossa percentage – volume of the rostral cranial fossa/volume of cranial cavity × 100 (volRCF/volCC × 100) was lower in small and brachycephalic dog breeds than in the other dogs. Conclusions A reduced RCF volume was detected in small and brachycephalic dog breeds, some of which are predisposed to congenital hydrocephalus. This may lead to overcrowding of brain parenchyma in the RCF and may impede CSF circulation. Our observations may be useful for future studies focusing on the causes and new therapies to treat conditions such as hydrocephalus and syringomyelia. Electronic supplementary material The online version of this article (10.1186/s12917-018-1483-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Wojciech Sokołowski
- Department of Morphological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences - SGGW, Nowoursynowska 159, 02-776, Warsaw, Poland.
| | - Norbert Czubaj
- Department of Morphological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences - SGGW, Nowoursynowska 159, 02-776, Warsaw, Poland
| | - Michał Skibniewski
- Department of Morphological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences - SGGW, Nowoursynowska 159, 02-776, Warsaw, Poland
| | - Karolina Barszcz
- Department of Morphological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences - SGGW, Nowoursynowska 159, 02-776, Warsaw, Poland
| | - Marta Kupczyńska
- Department of Morphological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences - SGGW, Nowoursynowska 159, 02-776, Warsaw, Poland
| | - Wojciech Kinda
- Department of Surgery, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, Pl. Grunwaldzki 51, 50-366, Wroclaw, Poland
| | - Zdzisław Kiełbowicz
- Department of Surgery, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, Pl. Grunwaldzki 51, 50-366, Wroclaw, Poland
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16
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Andreis ME, Polito U, Veronesi MC, Faustini M, Di Giancamillo M, Modina SC. Novel contributions in canine craniometry: Anatomic and radiographic measurements in newborn puppies. PLoS One 2018; 13:e0196959. [PMID: 29738556 PMCID: PMC5940217 DOI: 10.1371/journal.pone.0196959] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 04/23/2018] [Indexed: 12/14/2022] Open
Abstract
The largest differences in intraspecific head shape among the Carnivora order are to be found in dogs. Based on their skull morphotypes, dog breeds are currently classified as dolichocephalic, mesaticephalic and brachycephalic. Due to the fact that some breeds have not been yet defined, this classification is incomplete; moreover, multi-breed studies on the skull morphology of puppies have never been performed. The aim of this work was to verify (i) whether differences in the skull conformation of purebred puppies are already present within the first week of age; (ii) whether radiographic and anatomic measures could be considered interchangeable, and (iii) to possibly classify puppies from non-categorized breeds thanks to their radiographic cranial measurements using neural nets. One hundred and thirty-seven dead puppies aged 0–7 days were examined considering their anatomic and radiographic measures. All linear measures and anatomic indices significantly differed among brachycephalic and non-brachycephalic puppies. Radiographic indices, with the exception of CI, identified the three skull morphotypes (p<0.05, for all comparisons). Radiographic and anatomic measures proved to be non-interchangeable in newborn puppies. Finally, nineteen puppies belonging to 5 non-categorized breeds could be classified thanks to neural nets in the three skull morphotypes with different probability (P between 0,66 and 0,95).
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Affiliation(s)
- Maria Elena Andreis
- Department of Health, Animal Science and Food Safety, Università degli Studi di Milano, Milano, Italy
| | - Umberto Polito
- Department of Health, Animal Science and Food Safety, Università degli Studi di Milano, Milano, Italy
| | | | - Massimo Faustini
- Department of Veterinary Medicine, Università degli Studi di Milano, Milano, Italy
| | - Mauro Di Giancamillo
- Department of Veterinary Medicine, Università degli Studi di Milano, Milano, Italy
- * E-mail:
| | - Silvia C. Modina
- Department of Health, Animal Science and Food Safety, Università degli Studi di Milano, Milano, Italy
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17
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Nitzsche B, Boltze J, Ludewig E, Flegel T, Schmidt MJ, Seeger J, Barthel H, Brooks OW, Gounis MJ, Stoffel MH, Schulze S. A stereotaxic breed-averaged, symmetric T2w canine brain atlas including detailed morphological and volumetrical data sets. Neuroimage 2018; 187:93-103. [PMID: 29407456 DOI: 10.1016/j.neuroimage.2018.01.066] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 01/17/2018] [Accepted: 01/25/2018] [Indexed: 12/23/2022] Open
Abstract
Stereotaxic systems and automatic tissue segmentation routines enable neuronavigation as well as reproducible processing of neuroimage datasets. Such systems have been developed for humans, non-human-primates, sheep, and rodents, but not for dogs. Although dogs share important neurofunctional and -anatomical features with humans, and in spite of their importance in translational neuroscience, little is known about the variability of the canine brain morphology and, possibly related, function. Moreover, we lack templates, tissue probability maps (TPM), and stereotaxic brain labels for implementation in standard software utilities such as Statistical Parametric Mapping (SPM). Hence, objective and reproducible, image-based investigations are currently impeded in dogs. We have created a detailed stereotaxic reference frame for dogs including TPM and tissue labels, enabling inter-individual and cross-study neuroimage analysis. T2w datasets were acquired from 16 neurologically inconspicuous dogs of different breeds by 3T MRI. The datasets were averaged after initial preprocessing using linear and nonlinear registration algorithms as implemented in SPM8. TPM for gray (GM) and white matter (WM) as well as cerebrospinal fluid (CSF) were created. Different cortical, subcortical, medullary, and CSF regions were manually labeled to create a spatial binary atlas being aligned with the template. A proof-of-concept for automatic determination of morphological and volumetrical characteristics was performed using additional canine datasets (n = 64) including a subgroup of laboratory beagles (n = 24). Overall, 21 brain regions were labeled using the segmented tissue classes of the brain template. The proof-of-concept trial revealed excellent suitability of the created tools for image processing and subsequent analysis. There was high intra-breed variability in frontal lobe and hippocampus volumes, and noticeable inter-breed corpus callosum volume variation. The T2w brain template provides important, breed-averaged canine brain anatomy features in a spatial standard coordinate system. TPM allows automatic tissue segmentation using SPM and enables unbiased automatic image processing or morphological characterization in different canine breeds. The reported volumetric and morphometric results may serve as a starting point for further research aimed at in vivo analysis of canine brain anatomy and function.
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Affiliation(s)
- Björn Nitzsche
- Department for Nuclear Medicine, University Hospital of Leipzig, Leipzig, Germany; Institute of Anatomy, Histology and Embryology, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany.
| | - Johannes Boltze
- Department of Translational Medicine and Cell Technology, Fraunhofer Research Institution for Marine Biotechnology and Cell Technology, Institute of Medical and Marine Biotechnology, University of Lübeck, Lübeck, Germany
| | - Eberhard Ludewig
- Clinic Unit of Diagnostic Imaging, University of Veterinary Medicine Vienna, Austria
| | - Thomas Flegel
- Department of Small Animals Medicine, Veterinary Faculty, University of Leipzig, Leipzig, Germany
| | - Martin J Schmidt
- Department of Veterinary Clinical Sciences, Clinic for Small Animals - Neurosurgery, Neuroradiology and Clinical Neurology, Faculty of Veterinary Medicine, Justus-Liebig-University Gießen, Gießen, Germany
| | - Johannes Seeger
- Institute of Anatomy, Histology and Embryology, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany
| | - Henryk Barthel
- Department for Nuclear Medicine, University Hospital of Leipzig, Leipzig, Germany
| | - Olivia W Brooks
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, MA, USA
| | - Matthew J Gounis
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, MA, USA
| | - Michael H Stoffel
- Division of Veterinary Anatomy, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Sabine Schulze
- Department of Veterinary Clinical Sciences, Clinic for Small Animals - Neurosurgery, Neuroradiology and Clinical Neurology, Faculty of Veterinary Medicine, Justus-Liebig-University Gießen, Gießen, Germany
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18
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Bankstahl M, Bankstahl JP. Recent Advances in Radiotracer Imaging Hold Potential for Future Refined Evaluation of Epilepsy in Veterinary Neurology. Front Vet Sci 2017; 4:218. [PMID: 29326952 PMCID: PMC5733338 DOI: 10.3389/fvets.2017.00218] [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: 09/27/2017] [Accepted: 11/30/2017] [Indexed: 12/26/2022] Open
Abstract
Non-invasive nuclear imaging by positron emission tomography and single photon emission computed tomography has significantly contributed to epileptic focus localization in human neurology for several decades now. Offering functional insight into brain alterations, it is also of particular relevance for epilepsy research. Access to these techniques for veterinary medicine is becoming more and more relevant and has already resulted in first studies in canine patients. In view of the substantial proportion of drug-refractory epileptic dogs and cats, image-guided epileptic focus localization will be a prerequisite for selection of patients for surgical focus resection. Moreover, radiotracer imaging holds potential for a better understanding of the pathophysiology of underlying epilepsy syndromes as well as to forecast disease risk after epileptogenic brain insults. Importantly, recent advances in epilepsy research demonstrate the suitability and value of several novel radiotracers for non-invasive assessment of neuroinflammation, blood–brain barrier alterations, and neurotransmitter systems. It is desirable that veterinary epilepsy patients will also benefit from these promising developments in the medium term. This paper reviews the current use of radiotracer imaging in the veterinary epilepsy patient and suggests possible future directions for the technique.
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Affiliation(s)
- Marion Bankstahl
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Center of Systems Neuroscience Hannover, Hannover, Germany
| | - Jens P Bankstahl
- Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany
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19
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Kiviranta AM, Rusbridge C, Laitinen-Vapaavuori O, Hielm-Björkman A, Lappalainen AK, Knowler SP, Jokinen TS. Syringomyelia and Craniocervical Junction Abnormalities in Chihuahuas. J Vet Intern Med 2017; 31:1771-1781. [PMID: 28892202 PMCID: PMC5697179 DOI: 10.1111/jvim.14826] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 06/19/2017] [Accepted: 08/07/2017] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND Chiari-like malformation (CM) and syringomyelia (SM) are widely reported in Cavalier King Charles Spaniels and Griffon Bruxellois dogs. Increasing evidence indicates that CM and SM also occur in other small and toy breed dogs, such as Chihuahuas. OBJECTIVES To describe the presence of SM and craniocervical junction (CCJ) abnormalities in Chihuahuas and to evaluate the possible association of CCJ abnormalities with SM. To describe CM/SM-related clinical signs and neurologic deficits and to investigate the association of CM/SM-related clinical signs with signalment, SM, or CCJ abnormalities. ANIMALS Fifty-three client-owned Chihuahuas. METHODS Prospective study. Questionnaire analyses and physical and neurologic examinations were obtained before magnetic resonance and computed tomography imaging. Images were evaluated for the presence of SM, CM, and atlantooccipital overlapping. Additionally, medullary kinking, dorsal spinal cord compression, and their sum indices were calculated. RESULTS Scratching was the most common CM/SM-related clinical sign and decreased postural reaction the most common neurologic deficit in 73 and 87% of dogs, respectively. Chiari-like malformation and SM were present in 100 and 38% of dogs, respectively. Syringomyelia was associated with the presence of CM/SM-related clinical signs (P = 0.034), and medullary kinking and sum indices were higher in dogs with clinical signs (P = 0.016 and P = 0.007, respectively). CONCLUSIONS AND CLINICAL IMPORTANCE Syringomyelia and CCJ abnormalities are prevalent in Chihuahuas. Syringomyelia was an important factor for the presence of CM/SM-related clinical signs, but many dogs suffered from similar clinical signs without being affected by SM, highlighting the clinical importance of CCJ abnormalities in Chihuahuas.
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Affiliation(s)
- A-M Kiviranta
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland
| | - C Rusbridge
- and School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, Surrey, UK
| | - O Laitinen-Vapaavuori
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland
| | - A Hielm-Björkman
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland
| | - A K Lappalainen
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland
| | - S P Knowler
- and School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, Surrey, UK
| | - T S Jokinen
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland
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20
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Schmidt MJ, Kolecka M, Kirberger R, Hartmann A. Dynamic Susceptibility Contrast Perfusion Magnetic Resonance Imaging Demonstrates Reduced Periventricular Cerebral Blood Flow in Dogs with Ventriculomegaly. Front Vet Sci 2017; 4:137. [PMID: 28879204 PMCID: PMC5572229 DOI: 10.3389/fvets.2017.00137] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 08/09/2017] [Indexed: 12/31/2022] Open
Abstract
The nature of ventriculomegaly in dogs is still a matter of debate. Signs of increased intraventricular pressure and atrophy of the cerebral white matter have been found in dogs with ventriculomegaly, which would imply increased intraventricular pressure and, therefore, a pathological condition, i.e., to some extent. Reduced periventricular blood flow was found in people with high elevated intraventricular pressure. The aim of this study was to compare periventricular brain perfusion in dogs with and without ventriculomegaly using perfusion weighted-magnetic-resonance-imaging to clarify as to whether ventriculomegaly might be associated with an increase in intraventricular pressure. Perfusion was measured in 32 Cavalier King Charles spaniels (CKCS) with ventriculomegaly, 10 CKCSs were examined as a control group. Cerebral blood flow (CBF) was measured using free-hand regions of interest (ROI) in five brain regions: periventricular white matter, caudate nucleus, parietal cortex, hippocampus, and thalamus. CBF was significantly lower in the periventricular white matter of the dogs with ventriculomegaly (p = 0.0029) but not in the other ROIs. Reduction of periventricular CBF might imply increase of intraventricular pressure in ventriculomegaly.
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Affiliation(s)
- Martin J Schmidt
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Justus-Liebig-University Giessen, Giessen, Germany
| | - Malgorzata Kolecka
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Justus-Liebig-University Giessen, Giessen, Germany
| | - Robert Kirberger
- Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
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21
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Schmidt MJ, Kampschulte M, Enderlein S, Gorgas D, Lang J, Ludewig E, Fischer A, Meyer-Lindenberg A, Schaubmar AR, Failing K, Ondreka N. The Relationship between Brachycephalic Head Features in Modern Persian Cats and Dysmorphologies of the Skull and Internal Hydrocephalus. J Vet Intern Med 2017; 31:1487-1501. [PMID: 28833532 PMCID: PMC5598898 DOI: 10.1111/jvim.14805] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 06/01/2017] [Accepted: 07/13/2017] [Indexed: 01/06/2023] Open
Abstract
Background Cat breeders observed a frequent occurrence of internal hydrocephalus in Persian cats with extreme brachycephalic head morphology. Objective To investigate a possible relationship among the grade of brachycephaly, ventricular dilatation, and skull dysmorphologies in Persian cats. Animals 92 Persian‐, 10 Domestic shorthair cats. Methods The grade of brachycephaly was determined on skull models based on CT datasets. Cranial measurements were examined with regard to a possible correlation with relative ventricular volume, and cranial capacity. Persians with high (peke‐face Persians) and lower grades of brachycephaly (doll‐face Persians) were investigated for the presence of skull dysmorphologies. Results The mean cranial index of the peke‐face Persians (0.97 ± 0.14) was significantly higher than the mean cranial index of doll‐face Persians (0.66 ± 0.04; P < 0.001). Peke‐face Persians had a lower relative nasal bone length (0.15 ± 0.04) compared to doll‐face (0.29 ± 0.08; P < 0.001). The endocranial volume was significantly lower in doll‐face than peke‐face Persians (89.6 ± 1.27% versus 91.76 ± 2.07%; P < 0.001). The cranial index was significantly correlated with this variable (Spearman's r: 0.7; P < 0.0001). Mean ventricle: Brain ratio of the peke‐face group (0.159 ± 0.14) was significantly higher compared to doll‐face Persians (0.015 ± 0.01; P < 0.001). Conclusion and Clinical Relevance High grades of brachycephaly are also associated with malformations of the calvarial and facial bones as well as dental malformations. As these dysmorphologies can affect animal welfare, the selection for extreme forms of brachycephaly in Persian cats should be reconsidered.
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Affiliation(s)
- M J Schmidt
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Justus-Liebig University, Giessen, Germany
| | - M Kampschulte
- Department of Diagnostic and Interventional Radiology, University Hospital Gießen, Gießen, Germany
| | - S Enderlein
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Justus-Liebig University, Giessen, Germany
| | - D Gorgas
- Vetsuisse Faculty Berne, Clinical Radiology, Berne, Switzerland
| | - J Lang
- Vetsuisse Faculty Berne, Clinical Radiology, Berne, Switzerland
| | - E Ludewig
- Department of Companion Animals and Horses, University of Veterinary Medicine, Vienna, Austria
| | - A Fischer
- Section of Neurology, Clinic of Small Animal Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - A Meyer-Lindenberg
- Clinic of Small Animal Surgery and Reproduction, Ludwig Maximilians-University, Munich, Germany
| | - A R Schaubmar
- Unit for Biomathematics and Data Processing, Faculty of Veterinary Medicine, Justus Liebig-University, Giessen, Germany
| | - K Failing
- Unit for Biomathematics and Data Processing, Faculty of Veterinary Medicine, Justus Liebig-University, Giessen, Germany
| | - N Ondreka
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Justus-Liebig University, Giessen, Germany
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22
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Milne ME, Steward C, Firestone SM, Long SN, O'Brien TJ, Moffat BA. Development of representative magnetic resonance imaging-based atlases of the canine brain and evaluation of three methods for atlas-based segmentation. Am J Vet Res 2016; 77:395-403. [PMID: 27027839 DOI: 10.2460/ajvr.77.4.395] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To develop representative MRI atlases of the canine brain and to evaluate 3 methods of atlas-based segmentation (ABS). ANIMALS 62 dogs without clinical signs of epilepsy and without MRI evidence of structural brain disease. PROCEDURES The MRI scans from 44 dogs were used to develop 4 templates on the basis of brain shape (brachycephalic, mesaticephalic, dolichocephalic, and combined mesaticephalic and dolichocephalic). Atlas labels were generated by segmenting the brain, ventricular system, hippocampal formation, and caudate nuclei. The MRI scans from the remaining 18 dogs were used to evaluate 3 methods of ABS (manual brain extraction and application of a brain shape-specific template [A], automatic brain extraction and application of a brain shape-specific template [B], and manual brain extraction and application of a combined template [C]). The performance of each ABS method was compared by calculation of the Dice and Jaccard coefficients, with manual segmentation used as the gold standard. RESULTS Method A had the highest mean Jaccard coefficient and was the most accurate ABS method assessed. Measures of overlap for ABS methods that used manual brain extraction (A and C) ranged from 0.75 to 0.95 and compared favorably with repeated measures of overlap for manual extraction, which ranged from 0.88 to 0.97. CONCLUSIONS AND CLINICAL RELEVANCE Atlas-based segmentation was an accurate and repeatable method for segmentation of canine brain structures. It could be performed more rapidly than manual segmentation, which should allow the application of computer-assisted volumetry to large data sets and clinical cases and facilitate neuroimaging research and disease diagnosis.
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23
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Carreira LM. Using Bronson Equation to Accurately Predict the Dog Brain Weight Based on Body Weight Parameter. Vet Sci 2016; 3:vetsci3040036. [PMID: 29056744 PMCID: PMC5606585 DOI: 10.3390/vetsci3040036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Revised: 11/20/2016] [Accepted: 11/29/2016] [Indexed: 12/03/2022] Open
Abstract
The study used 69 brains (n = 69) from adult dog cadavers, divided by their skull type into three groups, brachi (B), dolicho (D) and mesaticephalic (M) (n = 23 each), and aimed: (1) to determine whether the Bronson equation may be applied, without reservation, to estimate brain weight (BW) in brachy (B), dolicho (D), and mesaticephalic (M) dog breeds; and (2) to evaluate which breeds are more closely related to each other in an evolutionary scenario. All subjects were identified by sex, age, breed, and body weight (bw). An oscillating saw was used for a circumferential craniotomy to open the skulls; the brains were removed and weighed using a digital scale. For statistical analysis, p-values < 0.05 were considered significant. The work demonstrated a strong relationship between the observed and predicted BW by using the Bronson equation. It was possible to hypothesize that groups B and D present a greater encephalization level than M breeds, that B and D dog breeds are more closely related to each other than to M, and from the three groups, the D individuals presented the highest brain mass mean.
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Affiliation(s)
- L Miguel Carreira
- Faculty of Veterinary Medicine, University of Lisbon (FMV/ULisboa), Av. da Universidade Técnica de Lisboa, Polo Universitário Alto da Ajuda, Lisbon 1300-477, Portugal.
- Centre for Interdisciplinary Research in Animal Health (CIISA), FMV/ULisboa, Av. da Universidade Técnica de Lisboa, Polo Universitário Alto da Ajuda, Lisbon 1300-477, Portugal.
- Anjos of Assis Veterinary Medicine Centre (CMVAA), Rua Dª. Francisca da Azambuja Nº 9-9A, Barreiro 2830-077, Portugal.
- Private Practice in Human Dentistry, Oral Medicine and Surgery Clinic, Lisbon 1300-477, Portugal.
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24
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Lewis MJ, Olby NJ, Early PJ, Mariani CL, Muñana KR, Seiler GS, Griffith EH. Clinical and Diagnostic Imaging Features of Brain Herniation in Dogs and Cats. J Vet Intern Med 2016; 30:1672-1680. [PMID: 27616749 PMCID: PMC5032863 DOI: 10.1111/jvim.14526] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 05/19/2016] [Accepted: 06/27/2016] [Indexed: 11/28/2022] Open
Abstract
Background Quantification of brain herniation on MRI and its immediate clinical implications are poorly described. Objectives Define the normal position of caudal fossa structures on brain MRIs in dogs and cats utilizing morphometry, compare this to dogs and cats with caudal transtentorial herniation (CTH), foramen magnum herniation (FMH) or both identified on MRI, and investigate associations between herniation severity, clinical signs, and 24‐hour outcome. Animals Ninety‐two controls (66 dogs, 26 cats), 119 cases with herniation (88 dogs, 31 cats). Methods Retrospective case series. The MRI database was searched for controls with normal brain anatomy and cases with brain herniation. Morphometry in controls established TTX (transtentorial to rostroventral cerebellum) to quantify CTH and FMX (caudoventral cerebellum to foramen magnum) to quantify FMH. Measurements were compared between cases and controls. Correlations with specific clinical variables and outcome were investigated. Results Measurements in medium/large control dogs versus small dog and cat controls were significantly different (P < .001, TTX: −0.46, −0.305, −0.3, FMX: 0.695, 0.27, 0.25, respectively). 119/1564 (7.6%) cases that underwent brain imaging had brain herniation. TTX and FMX were significantly different between controls and cases with CTH or FMH (P < .001). 67/89 (75%) cases with supratentorial lesions had no signs directly attributable to herniation. 71/119 (60%) had a normal anesthetic recovery. TTX was significantly associated with 24‐hour survival (P < .001). Conclusions and clinical importance Brain herniation can be quantified on MRI. Clinical signs directly attributable to brain herniation commonly are absent, and more severe CTH based on TTX is associated with a worse short‐term outcome.
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Affiliation(s)
- M J Lewis
- College of Veterinary Medicine, NCSU, Raleigh, NC.,Comparative Medicine Institute, NCSU, Raleigh, NC
| | - N J Olby
- College of Veterinary Medicine, NCSU, Raleigh, NC. .,Comparative Medicine Institute, NCSU, Raleigh, NC.
| | - P J Early
- College of Veterinary Medicine, NCSU, Raleigh, NC
| | - C L Mariani
- College of Veterinary Medicine, NCSU, Raleigh, NC.,Comparative Medicine Institute, NCSU, Raleigh, NC
| | - K R Muñana
- College of Veterinary Medicine, NCSU, Raleigh, NC
| | - G S Seiler
- College of Veterinary Medicine, NCSU, Raleigh, NC
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25
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Magnetic resonance imaging-based measures of atlas position: Relationship to canine atlantooccipital overlapping, syringomyelia and clinical signs. Vet J 2016; 209:133-8. [DOI: 10.1016/j.tvjl.2016.01.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 12/22/2015] [Accepted: 01/11/2016] [Indexed: 11/18/2022]
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26
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Nitzsche B, Frey S, Collins LD, Seeger J, Lobsien D, Dreyer A, Kirsten H, Stoffel MH, Fonov VS, Boltze J. A stereotaxic, population-averaged T1w ovine brain atlas including cerebral morphology and tissue volumes. Front Neuroanat 2015; 9:69. [PMID: 26089780 PMCID: PMC4455244 DOI: 10.3389/fnana.2015.00069] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Accepted: 05/12/2015] [Indexed: 01/18/2023] Open
Abstract
Standard stereotaxic reference systems play a key role in human brain studies. Stereotaxic coordinate systems have also been developed for experimental animals including non-human primates, dogs, and rodents. However, they are lacking for other species being relevant in experimental neuroscience including sheep. Here, we present a spatial, unbiased ovine brain template with tissue probability maps (TPM) that offer a detailed stereotaxic reference frame for anatomical features and localization of brain areas, thereby enabling inter-individual and cross-study comparability. Three-dimensional data sets from healthy adult Merino sheep (Ovis orientalis aries, 12 ewes and 26 neutered rams) were acquired on a 1.5 T Philips MRI using a T1w sequence. Data were averaged by linear and non-linear registration algorithms. Moreover, animals were subjected to detailed brain volume analysis including examinations with respect to body weight (BW), age, and sex. The created T1w brain template provides an appropriate population-averaged ovine brain anatomy in a spatial standard coordinate system. Additionally, TPM for gray (GM) and white (WM) matter as well as cerebrospinal fluid (CSF) classification enabled automatic prior-based tissue segmentation using statistical parametric mapping (SPM). Overall, a positive correlation of GM volume and BW explained about 15% of the variance of GM while a positive correlation between WM and age was found. Absolute tissue volume differences were not detected, indeed ewes showed significantly more GM per bodyweight as compared to neutered rams. The created framework including spatial brain template and TPM represent a useful tool for unbiased automatic image preprocessing and morphological characterization in sheep. Therefore, the reported results may serve as a starting point for further experimental and/or translational research aiming at in vivo analysis in this species.
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Affiliation(s)
- Björn Nitzsche
- Department of Cell Therapy, Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany ; Faculty of Veterinary Medicine, Institute of Anatomy, Histology and Embryology, University of Leipzig Leipzig, Germany
| | - Stephen Frey
- McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University Montreal, QC, Canada
| | - Louis D Collins
- McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University Montreal, QC, Canada
| | - Johannes Seeger
- Faculty of Veterinary Medicine, Institute of Anatomy, Histology and Embryology, University of Leipzig Leipzig, Germany
| | - Donald Lobsien
- Department of Neuroradiology, University Hospital of Leipzig Leipzig, Germany
| | - Antje Dreyer
- Department of Cell Therapy, Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany ; Translational Centre for Regenerative Medicine, University of Leipzig Leipzig, Germany
| | - Holger Kirsten
- Department of Cell Therapy, Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany ; Faculty of Medicine, Institute for Medical Informatics, Statistics and Epidemiology, University of Leipzig Leipzig, Germany ; LIFE Center (Leipzig Interdisciplinary Research Cluster of Genetic Factors, Phenotypes and Environment), University of Leipzig Leipzig, Germany
| | - Michael H Stoffel
- Division of Veterinary Anatomy, Vetsuisse Faculty, University of Bern Bern, Switzerland
| | - Vladimir S Fonov
- McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University Montreal, QC, Canada
| | - Johannes Boltze
- Department of Cell Therapy, Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany ; Translational Centre for Regenerative Medicine, University of Leipzig Leipzig, Germany ; Neurovascular Regulation Laboratory at Neuroscience Center, Massachusetts General Hospital and Harvard Medical School Charlestown, MA, USA
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27
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Ashwell KWS. Quantitative analysis of somatosensory cortex development in eutherians, with a comparison with metatherians and monotremes. Somatosens Mot Res 2015; 32:137-52. [DOI: 10.3109/08990220.2015.1004046] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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