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Barton SA, Kent M, Hecht EE. Covariation of Skull and Brain Morphology in Domestic Dogs. J Comp Neurol 2024; 532:e25668. [PMID: 39268838 DOI: 10.1002/cne.25668] [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: 01/29/2024] [Revised: 07/12/2024] [Accepted: 08/22/2024] [Indexed: 09/15/2024]
Abstract
Despite their distinct embryonic origins, the skull and brain are highly integrated. Understanding the covariation between the skull and brain can shed light on anatomical, cognitive, and behavioral traits in extant and extinct species. Domestic dogs offer a unique opportunity to investigate skull-brain covariation due to their diverse skull morphologies and neural anatomy. To assess this question, we examined T2-weighted MRI studies of 62 dogs from 33 breeds, plus an additional 17 dogs of mixed or unknown breeds. Scans were opportunistically collected from a veterinary teaching hospital of dogs that were referred for neurological examination but did not have grossly observable structural brain abnormalities. As the neurocrania of dogs become broader and shorter, there is a significant decrease in the gray matter volume of the right olfactory bulb, frontal cortex, marginal gyrus, and cerebellum. On the other hand, as the neurocrania of dogs become narrower and longer, there is a significant decrease in the gray matter volume of the olfactory bulb, frontal cortex, temporal cortex, amygdala, hypothalamus, hippocampus, periaqueductal gray, cerebellum, and brainstem. Selective breeding for specific skull shapes may impact canine brain anatomy and function.
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Affiliation(s)
- Sophie A Barton
- Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Marc Kent
- College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Erin E Hecht
- Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
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2
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Turcsán B, Kubinyi E. Differential behavioral aging trajectories according to body size, expected lifespan, and head shape in dogs. GeroScience 2024; 46:1731-1754. [PMID: 37740140 PMCID: PMC10828231 DOI: 10.1007/s11357-023-00945-9] [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: 03/28/2023] [Accepted: 09/12/2023] [Indexed: 09/24/2023] Open
Abstract
The twofold life expectancy difference between dog breeds predicts differential behavioral and cognitive aging patterns between short- and long-lived dogs. To investigate this prediction, we conducted a cross-sectional analysis using survey data from over 15,000 dogs. We examined the effect of expected lifespan and three related factors (body size, head shape, and purebred status) on the age trajectory of various behavioral characteristics and the prevalence of canine cognitive dysfunction (CCD). Our findings reveal that, although age-related decline in most behavioral characteristics began around 10.5 years of age, the proportion of dogs considered "old" by their owners began to increase uniformly around 6 years of age. From the investigated factors, only body size had a systematic, although not gradual, impact on the aging trajectories of all behavioral characteristics. Dogs weighing over 30 kg exhibited an earlier onset of decline by 2-3 years and a slower rate of decline compared to smaller dogs, probably as a byproduct of their faster age-related physical decline. Larger sized dogs also showed a lower prevalence of CCD risk in their oldest age group, whereas smaller-sized dogs, dolichocephalic breeds, and purebreds had a higher CCD risk prevalence. The identification of differential behavioral and cognitive aging trajectories across dog groups, and the observed associations between body size and the onset, rate, and degree of cognitive decline in dogs have significant translational implications for human aging research, providing valuable insights into the interplay between morphology, physiological ageing, and cognitive decline, and unravelling the trade-off between longevity and relative healthspan.
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Affiliation(s)
- Borbála Turcsán
- MTA-ELTE Lendület "Momentum" Companion Animal Research Group, Department of Ethology, Eötvös Loránd University, Budapest, Hungary.
- Senior Family Dog Project, Department of Ethology, Eötvös Loránd University, Budapest, Hungary.
| | - Enikő Kubinyi
- MTA-ELTE Lendület "Momentum" Companion Animal Research Group, Department of Ethology, Eötvös Loránd University, Budapest, Hungary
- Senior Family Dog Project, Department of Ethology, Eötvös Loránd University, Budapest, Hungary
- ELTE NAP Canine Brain Research Group, Budapest, Hungary
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Araújo GVD, de Souza-Junior P, Viana-Peçanha S, dos Santos-Sousa CA, Ramos MT, Bernardes FCS, Abidu-Figueiredo M. Linear CT-scan measurements of cerebral ventricles in senile Poodle dogs. BRAZILIAN JOURNAL OF VETERINARY MEDICINE 2023; 45:e004922. [PMID: 37288441 PMCID: PMC10243369 DOI: 10.29374/2527-2179.bjvm004922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Accepted: 05/09/2023] [Indexed: 06/09/2023] Open
Abstract
Breed traits seem to influence the dimensions of the cerebral ventricles in dogs. The ratios between the ventricles and the brain are crucial diagnostic criteria for suspected canine cognitive dysfunction (CCD). This study aimed to establish linear computed tomography (CT)-scan measurements of the cerebral ventricles in 55 Poodle dogs aged >7 years. To this end, cross-sectional CT images were evaluated. The measurements in the whole sample were: height of the right ventricle, 6.0 ± 1.6 mm; height of the left ventricle, 5.8 ± 1.6 mm; width of the right ventricle, 6.9 ± 1.4 mm; width of the left ventricle, 7.0 ± 1.3 mm; height of the third ventricle, 3.4 ± 0.8 mm; height of the right cerebral hemisphere, 39.5 ± 2.0 mm; and height of the left cerebral hemisphere, 40.2 ± 2.6 mm. The average ventricular measurements were higher in dogs older than 11 years (p < 0.05). However, the average ratio of the ventricle height to the height of the brain did not reveal differences between age groups, sex, or antimeres. In addition, none of the images showed fused lateral ventricles. Thus, these data can assist in interpreting ventricle size in senile Poodle dogs (aged >7 years).
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Affiliation(s)
- Glauce Vaz Diniz Araújo
- Veterinarian, Departamento de Anatomia Animal e Humana, Instituto de Ciências Biológicas e da Saúde (ICBS), Universidade Federal Rural do Rio de Janeiro (UFRRJ). Seropédica, Seropédica, RJ, Brazil.
| | - Paulo de Souza-Junior
- Veterinarian, DSc., Laboratório de Anatomia Animal, Universidade Federal do Pampa (UNIPAMPA). Uruguaiana, Uruguaiana, RS, Brazil.
| | - Shirley Viana-Peçanha
- Veterinarian, Programa de Pós-graduação em Medicina Veterinária da Universidade Federal Fluminense (UFF), Niterói, RJ, Brazil.
| | - Carlos Augusto dos Santos-Sousa
- Veterinarian, DSc., Centro de Ciências Biológicas e da Natureza, Universidade Federal do Acre (UFAC), Rio Branco, AC, Brazil.
| | - Marcia Torres Ramos
- Veterinarian, Curso de Medicina Veterinária, Universidade Estácio de Sá (UNESA), Niterói, RJ, Brazil
| | - Fernanda Coelho Simas Bernardes
- Veterinarian, Programa de Pós-graduação em Ciência Animal da Universidade Estadual de Santa Cruz (UESC), Ilhéus, BA, Brazil.
| | - Marcelo Abidu-Figueiredo
- Veterinarian, DSc., Departamento de Anatomia Animal e Humana, ICBS, UFRRJ. Seropédica, Seropédica, RJ, Brazil.
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Doiche DP, Rahal SC, Silva JPD, Oliveira FA, Miqueleto NSML, Mamprim MJ, Vulcano LC. Qualitative and quantitative evaluation of the ventricular system and brain parenchyma in healthy dogs of different skull conformation on computed tomography scans. Anat Histol Embryol 2021; 51:112-118. [PMID: 34854110 DOI: 10.1111/ahe.12767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 11/13/2021] [Accepted: 11/16/2021] [Indexed: 11/29/2022]
Abstract
This study aimed to perform quantitative and qualitative evaluations of the lateral and third ventricles, and brain parenchyma, in healthy dogs of different skull conformations on CT scans. Forty-five adult client-owned dogs were divided into three groups according to skull conformation: G1 (dolichocephalic)-15 German Shepherds; G2 (mesaticephalic)-15 Rottweilers; G3 (brachycephalic)-15 Boxers. Transverse plane images were used for quantitative and qualitative evaluations of the lateral ventricles and third ventricle, and pre- and post-contrast brain parenchyma. The height of both ventricles and brain was measured at the level of the interthalamic adhesion. Ventricle height, brain height, and ventricle/brain height ratio were statistically higher in G3 compared with G1 and G2 that were similar. The third ventricle was visible but unmeasurable in five dogs from G1 and three from G2. In G3, all dogs had third ventricle visible and measurable in all images. Asymmetric ventricles were seen in five dogs in Group 1 and Group 2, and seven in Group 3. Brain parenchyma had homogenous density in 80% of the dogs in all groups. Contrast enhancement of the rostral midline was visualized in all dogs. In conclusion, brain CT scans of healthy dogs showed that the qualitative data were similar among groups, but lateral ventricle and brain measurements in brachycephalic dogs differed from the dolichocephalic and mesaticephalic dogs.
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Affiliation(s)
- Danuta Pulz Doiche
- Department of Animal Reproduction and Veterinary Surgery, School of Veterinary Medicine and Animal Science-São Paulo State University (UNESP), Botucatu, Brazil
| | - Sheila Canevese Rahal
- Department of Animal Reproduction and Veterinary Surgery, School of Veterinary Medicine and Animal Science-São Paulo State University (UNESP), Botucatu, Brazil
| | - Jeana Pereira da Silva
- Department of Animal Reproduction and Veterinary Surgery, School of Veterinary Medicine and Animal Science-São Paulo State University (UNESP), Botucatu, Brazil
| | - Flávia Augusta Oliveira
- Department of Animal Reproduction and Veterinary Surgery, School of Veterinary Medicine and Animal Science-São Paulo State University (UNESP), Botucatu, Brazil
| | | | - Maria Jaqueline Mamprim
- Department of Animal Reproduction and Veterinary Surgery, School of Veterinary Medicine and Animal Science-São Paulo State University (UNESP), Botucatu, Brazil
| | - Luiz Carlos Vulcano
- Department of Animal Reproduction and Veterinary Surgery, School of Veterinary Medicine and Animal Science-São Paulo State University (UNESP), Botucatu, Brazil
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Barry EF, Loftus JP, Luh WM, de Leon MJ, Niogi SN, Johnson PJ. Diffusion tensor-based analysis of white matter in the healthy aging canine brain. Neurobiol Aging 2021; 105:129-136. [PMID: 34062488 DOI: 10.1016/j.neurobiolaging.2021.04.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 04/23/2021] [Accepted: 04/24/2021] [Indexed: 12/14/2022]
Abstract
White matter dysfunction and degeneration have been a topic of great interest in healthy and pathological aging. While ex vivo studies have investigated age-related changes in canines, little in vivo canine aging research exists. Quantitative diffusion MRI such as diffusion tensor imaging (DTI) has demonstrated aging and neurodegenerative white matter changes in humans. However, this method has not been applied and adapted in vivo to canine populations. This study aimed to test the hypothesis that white matter diffusion changes frequently reported in human aging are also found in aged canines. The study used Tract Based Spatial Statistics (TBSS) and a region of interest (ROI) approach to investigate age related changes in fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AxD) and radial diffusivity (RD). The results show that, compared to younger animals, aged canines have significant decreases in FA in parietal and temporal regions as well as the corpus callosum and fornix. Additionally, AxD decreases were observed in parietal, frontal, and midbrain regions. Similarly, an age- related increase in RD was observed in the right parietal lobe while MD decreases were found in the midbrain. These findings suggest that canine samples show commonalities with human brain aging as both exhibit similar white matter diffusion tensor changes with increasing age.
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Affiliation(s)
- Erica F Barry
- Cornell College of Veterinary Medicine, Cornell University, Ithaca, NY
| | - John P Loftus
- Cornell College of Veterinary Medicine, Cornell University, Ithaca, NY
| | - Wen-Ming Luh
- National Institute on Aging, Baltimore, Maryland
| | - Mony J de Leon
- Department of Radiology, Weill Cornell Medicine, New York, NY
| | - Sumit N Niogi
- Department of Radiology, Weill Cornell Medicine, New York, NY
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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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Hecht EE, Smaers JB, Dunn WD, Kent M, Preuss TM, Gutman DA. Significant Neuroanatomical Variation Among Domestic Dog Breeds. J Neurosci 2019; 39:7748-7758. [PMID: 31477568 PMCID: PMC6764193 DOI: 10.1523/jneurosci.0303-19.2019] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 08/08/2019] [Accepted: 08/13/2019] [Indexed: 02/07/2023] Open
Abstract
Humans have bred different lineages of domestic dogs for different tasks such as hunting, herding, guarding, or companionship. These behavioral differences must be the result of underlying neural differences, but surprisingly, this topic has gone largely unexplored. The current study examined whether and how selective breeding by humans has altered the gross organization of the brain in dogs. We assessed regional volumetric variation in MRI studies of 62 male and female dogs of 33 breeds. Neuroanatomical variation is plainly visible across breeds. This variation is distributed nonrandomly across the brain. A whole-brain, data-driven independent components analysis established that specific regional subnetworks covary significantly with each other. Variation in these networks is not simply the result of variation in total brain size, total body size, or skull shape. Furthermore, the anatomy of these networks correlates significantly with different behavioral specialization(s) such as sight hunting, scent hunting, guarding, and companionship. Importantly, a phylogenetic analysis revealed that most change has occurred in the terminal branches of the dog phylogenetic tree, indicating strong, recent selection in individual breeds. Together, these results establish that brain anatomy varies significantly in dogs, likely due to human-applied selection for behavior.SIGNIFICANCE STATEMENT Dog breeds are known to vary in cognition, temperament, and behavior, but the neural origins of this variation are unknown. In an MRI-based analysis, we found that brain anatomy covaries significantly with behavioral specializations such as sight hunting, scent hunting, guarding, and companionship. Neuroanatomical variation is not simply driven by brain size, body size, or skull shape, and is focused in specific networks of regions. Nearly all of the identified variation occurs in the terminal branches of the dog phylogenetic tree, indicating strong, recent selection in individual breeds. These results indicate that through selective breeding, humans have significantly altered the brains of different lineages of domestic dogs in different ways.
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Affiliation(s)
- Erin E Hecht
- Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138,
| | - Jeroen B Smaers
- Department of Anthropology, Stony Brook University, Stony Brook, New York 11794
| | - William D Dunn
- Departmentt of Neurology, School of Medicine, Emory University, Atlanta, Georgia 30329
| | - Marc Kent
- Department of Small Animal Medicine and Surgery, The University of Georgia at Athens, Athens, Georgia 30602
| | - Todd M Preuss
- Division of Neuropharmacology and Neurologic Diseases and Center for Translational Social Neuroscience, Yerkes National Primate Research Institute, Emory University, Atlanta, Georgia 30329
- Department of Pathology and Laboratory Medicine, School of Medicine, Emory University, Atlanta, Georgia 30329, and
| | - David A Gutman
- Department of Neurology, School of Medicine, Emory University, Atlanta, Georgia 30329
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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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Knowler SP, Galea GL, Rusbridge C. Morphogenesis of Canine Chiari Malformation and Secondary Syringomyelia: Disorders of Cerebrospinal Fluid Circulation. Front Vet Sci 2018; 5:171. [PMID: 30101146 PMCID: PMC6074093 DOI: 10.3389/fvets.2018.00171] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 07/04/2018] [Indexed: 01/01/2023] Open
Abstract
Chiari-like Malformation (CM) and secondary syringomyelia (SM), as well as their analogous human conditions, is a complex developmental condition associated with pain and accompanying welfare concerns. CM/SM is diagnosed ever more frequently, thanks in part to the increased availability of magnetic resonance imaging in veterinary medicine. Research over the last two decades has focused primarily on its pathophysiology relating to overcrowding of the cranial caudal fossa. More recent characterizations of CM/SM include brachycephaly with osseous reduction and neural parenchymal displacement involving the entire brain and craniocervical junction to include rostral flattening, olfactory bulb rotation, increased height of the cranium, reduced cranial base with spheno-occipital synchondrosis angulation, reduced supraoccipital and interparietal crest and rostral displacement of the axis and atlas with increased odontoid angulation. The most shared manifestation of CM is the development of fluid-filled pockets (syrinx, syringes) in the spinal cord that can be readily quantified. Dogs with symptomatic CM without SM have a reduced basioccipital bone, compensatory increased cranial fossa height with displaced parenchyma whereby the cerebellum is invaginated beneath the occipital lobes but without compromising cerebrospinal fluid channels enough to cause SM. Thus, broadly defined, CM might be described as any distortion of the skull and craniocervical junction which compromises the neural parenchyma and cerebrospinal fluid circulation causing pain and/or SM. The etiology of CM is multifactorial, potentially including genetically-influenced, breed-specific abnormalities in both skeletal and neural components. Since causation between specific morphologic changes and SM or clinical signs is unproven, CM might be more appropriately considered as a brachycephalic obstructive CSF channel syndrome (BOCCS) rather than a single malformation. Understanding the normal development of the brain, skull and craniocervical junction is fundamental to identifying deviations which predispose to CM/SM. Here we review its anatomical, embryological, bio-mechanical, and genetic underpinnings to update the profession's understanding of this condition and meaningfully inform future research to diminish its welfare impact.
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Affiliation(s)
- Susan P Knowler
- Department of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Gabriel L Galea
- Developmental Biology of Birth Defects, Great Ormond Street Institute of Child Health, University College London, London,, United Kingdom
| | - Clare Rusbridge
- Department of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom.,Fitzpatrick Referrals Veterinary Specialist Hospital, Surrey, United Kingdom
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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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11
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Moioli M, Levionnois O, Stein VM, Schüpbach G, Schmidhalter M, Schweizer-Gorgas D. Hyperintensity of Cerebrospinal Fluid on T2-Weighted Fluid-Attenuated Inversion Recovery Magnetic Resonance Imaging Caused by High Inspired Oxygen Fraction. Front Vet Sci 2017; 4:219. [PMID: 29326953 PMCID: PMC5741608 DOI: 10.3389/fvets.2017.00219] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 12/04/2017] [Indexed: 11/13/2022] Open
Abstract
In veterinary medicine, patients undergo magnetic resonance imaging (MRI) under general anesthesia to enable acquisition of artifact-free images. The fraction of inspired oxygen (FiO2) ranges between 30 and 95%. In humans, a high FiO2 is associated with incomplete signal suppression of peripheral cerebrospinal fluid (CSF) spaces on T2-weighted fluid-attenuated inversion recovery (T2w-FLAIR) sequences. The influence of FiO2 on T2w-FLAIR images remains unreported in small animals. The aim of this prospective study was to investigate whether a high FiO2 is associated with hyperintensity in peripheral CSF spaces on T2w-FLAIR images in dogs and cats. Client-owned patients undergoing brain MRI were prospectively enrolled. Animals with brain parenchymal abnormalities and/or meningeal contrast enhancement on MRI images and/or abnormal CSF analysis were excluded. Consequently, twelve patients were enrolled. Anesthesia was maintained by isoflurane 0.5-1 minimal alveolar concentration in 30% oxygen. After acquisition of transverse and dorsal T2w-FLAIR images, the FiO2 was increased to 95%. The T2w-FLAIR sequences were then repeated after 40 min. Arterial blood gas analysis was performed in six patients at the same time as T2w-FLAIR sequence acquisition. Plot profiles of the signal intensity (SI) from CSF spaces of three cerebral sulci and adjacent gray and white matter were generated. SI ratios of CSF space and white matter were compared between the T2w-FLAIR images with 30 and 95% FiO2. An observer blinded to the FiO2, subjectively evaluated the SI of peripheral CSF spaces on T2w-FLAIR images as high or low. There was significant difference in the partial pressure of oxygen between the two arterial samples (P < 0.001). The SI ratios obtained from the T2w-FLAIR images with 95% FiO2 were significantly higher compared with those obtained from the T2w-FLAIR images with 30% FiO2 (P < 0.05). The peripheral CSF spaces were subjectively considered hyperintense in 11 of 12 cases on T2w-FLAIR images with 95% FiO2 (P < 0.005). A clear difference in SI, dependent on the FiO2 was seen in the peripheral CSF spaces on T2w-FLAIR images. In conclusion, the influence of FiO2 must be considered when differentiating pathological and normal CSF spaces on T2w-FLAIR images in dogs and cats.
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Affiliation(s)
- Melania Moioli
- Clinical Radiology, Department of Clinical Veterinary Medicine, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
| | - Olivier Levionnois
- Clinical Anesthesiology, Department of Clinical Veterinary Medicine, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
| | - Veronika M Stein
- Clinical Neurology, Department of Clinical Veterinary Medicine, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
| | - Gertraud Schüpbach
- Department of Clinical Research and Veterinary Public Health, Veterinary Public Health Institute, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
| | - Marta Schmidhalter
- Clinical Radiology, Department of Clinical Veterinary Medicine, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
| | - Daniela Schweizer-Gorgas
- Clinical Radiology, Department of Clinical Veterinary Medicine, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
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