1
|
Santifort KM, Carrera I, Mandigers PJJ. Longitudinal assessment of syringomyelia in Pomeranians. Front Vet Sci 2024; 11:1364464. [PMID: 38751802 PMCID: PMC11094614 DOI: 10.3389/fvets.2024.1364464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 04/10/2024] [Indexed: 05/18/2024] Open
Abstract
Introduction Chiari-like malformation (CM) and syringomyelia (SM) are disorders that, in dogs, affect mainly small and toy breeds, including the Pomeranian. These disorders are linked to a great number of (owner-reported) clinical signs (ORCS) suggestive of pain. Aging was associated with an increased risk of having SM in several studies. However, there are only a few longitudinal studies that assess the presence and severity of CM/SM over time in CKCS dogs and progression of SM was linked to progression of clinical signs. The aim of this study was to investigate ORCS, CM/SM classification, and quantitative syrinx parameters in relation to progression of time (age) within individual Pomeranians. Materials and methods Pomeranians with or without ORCS and with or without diagnoses of CM/SM were included that had undergone two (or more) MRI studies of the craniocervicothoracic region between January 2020 and June 2023. Classification of CM/SM and quantitative syrinx measurements were performed. Absolute values as well as ratios for syrinx height, width, and cross-sectional area were included for analysis. Results A total of 19 Pomeranians were included in the study, of which 11 were male (58%) and 8 were female (42%). The median age at the time of MRI1 was 26 months (range 7-44 months). The median scan interval was 26 months (range 11-49 months). Eleven dogs (58%) were presented with ORCS at the time of MRI1, whereas the other 8 dogs (42%) had no ORCS at that time. At the time of MRI2, there were 17/19 dogs (89%) with ORCS and 2/19 dogs without ORCS (11%). Dogs were significantly more likely to have ORCS at MRI2 than MRI1 (p = 0. 0411). There was no significant difference between CM/SM classification at the time of MRI1 and MRI2. Significant differences were found between MRI1 and MRI2 for syrinx height (based on transverse images) (absolute value and ratio P = 0.0059), syrinx width (absolute value P = 0.1055, ratio P = 0.0039), and syrinx cross sectional area (absolute value P = 0.0195, ratio P = 0.0217). Discussion There are differences in the presence or absence of ORCS as well as quantitative syrinx measurements in Pomeranians at different ages. This finding supports that longitudinal changes occur in the SM status of Pomeranians.
Collapse
Affiliation(s)
- Koen M. Santifort
- IVC Evidensia Referral Hospital Arnhem, Neurology, Arnhem, Netherlands
- IVC Evidensia Referral Hospital Hart van Brabant, Neurology, Waalwijk, Netherlands
- Expertise Centre of Genetics, Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Ines Carrera
- Vet Oracle Teleradiology, Norfolk, United Kingdom
| | - Paul J. J. Mandigers
- IVC Evidensia Referral Hospital Arnhem, Neurology, Arnhem, Netherlands
- Expertise Centre of Genetics, Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| |
Collapse
|
2
|
Pedersen TR, Bach MBT, Stougaard CL, Gredal H, Rusbridge C, Finnerup NB, Berendt M. Clinical predictors of syringomyelia in Cavalier King Charles Spaniels with chiari-like malformation based on owners' observations. Acta Vet Scand 2024; 66:5. [PMID: 38331821 PMCID: PMC10851586 DOI: 10.1186/s13028-024-00725-1] [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: 09/20/2023] [Accepted: 01/17/2024] [Indexed: 02/10/2024] Open
Abstract
BACKGROUND Syringomyelia (SM) is a prevalent inherited developmental condition in Cavalier King Charles Spaniels (CKCSs) with Chiari-like malformation (CM), accompanied by a variety of clinical manifestations, including signs of neuropathic pain. Magnetic resonance imaging (MRI) is the gold standard in SM diagnosis. However, it is desirable to establish clinical predictors that can identify CKCSs with a large clinical syrinx that needs treatment, as some owners cannot afford or lack access to MRI. The aims of the study were to investigate owner-reported clinical signs of SM and clinical predictors of a large clinical syrinx, using predictive values of significant signs, individually and in combinations. Eighty-nine CKCSs participated in this retrospective study. Based on MRI diagnosis, dogs were distributed into three groups: CM without syrinx or with a maximum transverse width < 2 mm (n = 13), CM with small syrinx 2.00-3.99 mm (n = 26) and CM with large syrinx ≥4 mm (n = 50). A structured investigator-owner interview using a standardized questionnaire was used to collect data regarding clinical signs of CM and SM. The statistical tests Pearson's chi-square, Fisher's Exact and Spearman's rank order were used to assess the difference in owner-reported signs between groups. For signs with significant differences, positive and negative predictive values (PPV and NPV) were calculated. RESULTS Following clinical signs were reported significantly more frequent in dogs with a large syrinx: phantom scratching, bilateral scratching of the neck or shoulder, aversion when that area is touched, or exacerbation of clinical signs when the dog is emotionally aroused. Each individual sign had a high PPV, indicative of a large clinical syrinx. The PPV increased further when the signs phantom scratching, aversion to touch to the head, neck or shoulder, and a preferred head posture during sleep were present in combination. CONCLUSIONS Specific clinical signs can be used individually and in combination as clinical predictors of a large clinical syrinx in CKCSs with CM and SM. General practitioners can utilize this information to identify CKCSs with a large syrinx to initiate necessary treatment. This is particularly useful in cases where access to or affordability of an MRI diagnosis is limited.
Collapse
Affiliation(s)
- Tenna Remler Pedersen
- Department of Clinical Veterinary Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlaegevej 16, C DK-1870, Frederiksberg, Denmark.
| | - Maiken Bayer Thode Bach
- Department of Clinical Veterinary Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlaegevej 16, C DK-1870, Frederiksberg, Denmark
| | - Camilla Løkke Stougaard
- Department of Clinical Veterinary Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlaegevej 16, C DK-1870, Frederiksberg, Denmark
| | - Hanne Gredal
- Department of Clinical Veterinary Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlaegevej 16, C DK-1870, Frederiksberg, Denmark
| | - Clare Rusbridge
- Department of Clinical Sciences, School of Veterinary Medicine, University of Surrey, Daphne Jackson Rd, GU2 7AL, Guildford, Great Britain
| | - Nanna Brix Finnerup
- The Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Palle Juul-Jensens Boulevard 165, 8200, Aarhus N, Denmark
| | - Mette Berendt
- Department of Clinical Veterinary Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlaegevej 16, C DK-1870, Frederiksberg, Denmark
| |
Collapse
|
3
|
Santifort KM, Carrera I, Bossens K, Mandigers PJJ. Phenotypic characterization of Pomeranians with or without Chiari-like malformation and syringomyelia. Front Vet Sci 2023; 10:1320942. [PMID: 38169622 PMCID: PMC10758411 DOI: 10.3389/fvets.2023.1320942] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 12/04/2023] [Indexed: 01/05/2024] Open
Abstract
Introduction Chiari-like malformation (CM) and syringomyelia (SM) are frequently diagnosed conditions in small and toy dog breeds, such as the Cavalier King Charles Spaniel and Griffon Bruxellois. CM/SM is only rarely reported in Pomeranians in literature to date. The aims of this study are to 1/describe the phenotype of Pomeranians with or without CM/SM and 2/evaluate for differences and associations between CM/SM and owner-reported clinical signs (ORCS) or signalment factors. Materials and methods From February 2015 to June 2023, historical data and signalment (including country of origin, pedigree, sex and neuter status, age, and body weight) and ORCS of Pomeranians were recorded at multiple institutions. MRI studies of all dogs were evaluated for classification of CM/SM. Additionally, quantitative measurements were performed for SM. Results A total of 796 dogs from 22 different countries were included. Total prevalence of CM was 54.9% (437/796) and the prevalence of SM was 23.9% (190/796). The top 5 ORCS included 1/scratching with skin contact, rubbing head or ears, or both (57.6% of dogs with ORCS), 2/air licking (30.7% of dogs with ORCS), 3/spontaneous signs of pain (26.0% of dogs with ORCS), 4/persistent licking front and/or hind paws (22.6% of dogs with ORCS), 5/phantom scratching (22.6% of dogs with ORCS). Phantom scratching, vocalization, head shaking, spontaneous signs of pain, and air licking were associated with having SM. There were no statistically significant associations between quantitative syrinx measurements and ORCS. There were statistically significant associations between CM classification and 1/country of origin, 2/having a pedigree, and 3/age. There were statistically significant associations between SM classification and 1/age and 2/body weight. Discussion This is the first large study evaluating CM/SM in the Pomeranian dog breed. Veterinary clinicians can use these findings to increase the likelihood of correctly determining the presence or absence of CM/SM in Pomeranians. Breeders may consider using the information regarding signalment factors as well as ORCS associated with CM/SM classifications to select dogs for screening procedures. But an MRI-based diagnosis is needed to properly ascertain the exact CM/SM status of their breeding stock until a fool-proof characteristic or genetic marker is found.
Collapse
Affiliation(s)
- Koen M. Santifort
- Neurology, IVC Evidensia Referral Hospital Arnhem, Arnhem, Netherlands
- Neurology, IVC Evidensia Referral Hospital Hart van Brabant, Waalwijk, Netherlands
- Expertise Centre of Genetics, Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Ines Carrera
- Vet Oracle Teleradiology, Norfolk, United Kingdom
| | - Kenny Bossens
- Department of Neurology, Orion Small Animal Hospital, Herentals, Belgium
| | - Paul J. J. Mandigers
- Neurology, IVC Evidensia Referral Hospital Arnhem, Arnhem, Netherlands
- Expertise Centre of Genetics, Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| |
Collapse
|
4
|
Kiviranta AM, Rusbridge C, Lappalainen AK, Junnila JJT, Jokinen TS. Persistent fontanelles in Chihuahuas. Part II: Association with craniocervical junction abnormalities, syringomyelia, and ventricular volume. J Vet Intern Med 2021; 35:1848-1856. [PMID: 33939205 PMCID: PMC8295681 DOI: 10.1111/jvim.16123] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 03/31/2021] [Accepted: 04/01/2021] [Indexed: 12/13/2022] Open
Abstract
Background Persistent fontanelles (PFs) are, in Chihuahuas, almost ubiquitous. Furthermore, Chihuahuas are predisposed to other craniomorphological abnormalities, including syringomyelia (SM), ventriculomegaly, and craniocervical junction (CCJ) overcrowding resulting in neural tissue deviation. It is, however, undetermined if PFs are more common in dogs with these structural abnormalities, and their etiology is unknown. Hypothesis/Objectives Persistent fontanelles are more numerous and larger in Chihuahuas with low body weight, older age, SM, dilated fourth ventricle, ventriculomegaly, and CCJ overcrowding. Animals Fifty client‐owned Chihuahuas. Methods Cross‐sectional study evaluating the association of both the number of cranial sutures affected by PFs (NAS) and total fontanelle area (TFA), based on computed tomography with SM, fourth ventricle dilatation, lateral ventricle volume, and extent of neural tissue compression at the CCJ based on magnetic resonance images. Results The NASs was higher and TFA larger in dogs with low body weight (NAS: P = .007; 95% confidence interval [CI] = 0.384‐0.861; TFA: P = .002; 95% CI = −1.91 to −0.478), larger lateral ventricles (NAS: P ≤ .001; 95% CI = 1.04‐1.15; TFA: P ≤ .001; 95% CI = 0.099‐0.363), and more severe neural tissue compression at the CCJ (NAS: P ≤ .001; 95% CI = 1.26‐2.06; TFA: P = .03; 95% CI = 0.066‐1.13). Similarly, dogs with SM (NAS: P = .004; 95% CI = 1.26‐3.32; TFA: mean ± SD, 130 ± 217 mm2; P = .05) had higher NAS and larger TFA than did dogs without SM (43.7 ± 61.0 mm2). Age was not associated with NAS (P = .81; 95% CI = 0.989‐1.01) or TFA (P = .33; 95% CI = −0.269 to 0.092). Conclusions and Clinical Importance Persistent fontanelles are associated with small size, SM, ventriculomegaly, and CCJ overcrowding.
Collapse
Affiliation(s)
- Anna-Mariam Kiviranta
- Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Clare Rusbridge
- School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey, United Kingdom.,Fitzpatrick Referrals Halfway Lane, Eashing Godalming, Surrey, United Kingdom
| | - Anu K Lappalainen
- Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | | | - Tarja S Jokinen
- Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| |
Collapse
|
5
|
Knowler SP, Dumas E, Spiteri M, McFadyen AK, Stringer F, Wells K, Rusbridge C. Facial changes related to brachycephaly in Cavalier King Charles Spaniels with Chiari-like malformation associated pain and secondary syringomyelia. J Vet Intern Med 2019; 34:237-246. [PMID: 31691386 PMCID: PMC6979263 DOI: 10.1111/jvim.15632] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 09/23/2019] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Recent studies including an innovative machine learning technique indicated Chiari-like malformation (CM) is influenced by brachycephalic features. OBJECTIVES Morphometric analysis of facial anatomy and dysmorphia in CM-associated pain (CM-P) and syringomyelia (SM) in the Cavalier King Charles Spaniel (CKCS). ANIMALS Sixty-six client-owned CKCS. METHODS Retrospective study of anonymized T2W sagittal magnetic resonance imaging of 3 clinical groups: (1) 11 without central canal dilation (ccd) or SM (CM-N), (2) 15 with CM-P with no SM or <2 mm ccd (CM-P), and (3) 40 with syrinx width ≥4 mm (SM-S). Morphometric analysis assessed rostral skull flattening and position of the hard and soft palate relative to the cranial base in each clinical group and compared CKCS with and without SM-S. RESULTS Sixteen of 28 measured variables were associated to SM-S compared to CM-N and CM-P. Of these 6 were common to both groups. Predictive variables determined by discriminant analysis were (1) the ratio of cranial height with cranial length (P < .001 between SM-S and CM-N) and (2) the distance between the cerebrum and the frontal bone (P < .001 between SM-S and CM-P). CM-P had the lowest mean height of the maxillary area. CONCLUSIONS AND CLINICAL IMPORTANCE CKCS with CM-P and SM-S have cranial brachycephaly with osseous insufficiency in the skull with rostral flattening and increased proximity of the hard and soft palate to the cranial base. Changes are greatest with CM-P. These findings have relevance for understanding disease pathogenesis and for selection of head conformation for breeding purposes.
Collapse
Affiliation(s)
- Susan P Knowler
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, Daphne Jackson Road, Guildford, Surrey, GU7 Q22, United Kingdom
| | - Eleonore Dumas
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, Daphne Jackson Road, Guildford, Surrey, GU7 Q22, United Kingdom
| | - Michaela Spiteri
- Centre for Vision, Speech, and Signal Processing, University of Surrey, Guildford, GU2 7XH, United Kingdom
| | | | - Felicity Stringer
- Fitzpatrick Referrals Orthopaedics and Neurology, Halfway Lane, Eashing, Godalming, Surrey, GU7 Q22, United Kingdom
| | - Kevin Wells
- Centre for Vision, Speech, and Signal Processing, University of Surrey, Guildford, GU2 7XH, United Kingdom
| | - Clare Rusbridge
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, Daphne Jackson Road, Guildford, Surrey, GU7 Q22, United Kingdom.,Fitzpatrick Referrals Orthopaedics and Neurology, Halfway Lane, Eashing, Godalming, Surrey, GU7 Q22, United Kingdom
| |
Collapse
|
6
|
Spiteri M, Knowler SP, Rusbridge C, Wells K. Using machine learning to understand neuromorphological change and image-based biomarker identification in Cavalier King Charles Spaniels with Chiari-like malformation-associated pain and syringomyelia. J Vet Intern Med 2019; 33:2665-2674. [PMID: 31552689 PMCID: PMC6872629 DOI: 10.1111/jvim.15621] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 08/29/2019] [Indexed: 11/30/2022] Open
Abstract
Background Chiari‐like malformation (CM) is a complex malformation of the skull and cranial cervical vertebrae that potentially results in pain and secondary syringomyelia (SM). Chiari‐like malformation‐associated pain (CM‐P) can be challenging to diagnose. We propose a machine learning approach to characterize morphological changes in dogs that may or may not be apparent to human observers. This data‐driven approach can remove potential bias (or blindness) that may be produced by a hypothesis‐driven expert observer approach. Hypothesis/Objectives To understand neuromorphological change and to identify image‐based biomarkers in dogs with CM‐P and symptomatic SM (SM‐S) using a novel machine learning approach, with the aim of increasing the understanding of these disorders. Animals Thirty‐two client‐owned Cavalier King Charles Spaniels (CKCSs; 11 controls, 10 CM‐P, 11 SM‐S). Methods Retrospective study using T2‐weighted midsagittal Digital Imaging and Communications in Medicine (DICOM) anonymized images, which then were mapped to images of an average clinically normal CKCS reference using Demons image registration. Key deformation features were automatically selected from the resulting deformation maps. A kernelized support vector machine was used for classifying characteristic localized changes in morphology. Results Candidate biomarkers were identified with receiver operating characteristic curves with area under the curve (AUC) of 0.78 (sensitivity 82%; specificity 69%) for the CM‐P biomarkers collectively and an AUC of 0.82 (sensitivity, 93%; specificity, 67%) for the SM‐S biomarkers, collectively. Conclusions and clinical importance Machine learning techniques can assist CM/SM diagnosis and facilitate understanding of abnormal morphology location with the potential to be applied to a variety of breeds and conformational diseases.
Collapse
Affiliation(s)
- Michaela Spiteri
- CVSSP, Centre for Vision, Speech and Signal Processing, University of Surrey, Guildford, United Kingdom
| | - Susan P Knowler
- Faculty of Health & Medical Sciences, School of Veterinary Medicine, Guildford, United Kingdom
| | - Clare Rusbridge
- Faculty of Health & Medical Sciences, School of Veterinary Medicine, Guildford, United Kingdom.,Fitzpatrick Referrals Orthopaedics and Neurology, Godalming, United Kingdom
| | - Kevin Wells
- CVSSP, Centre for Vision, Speech and Signal Processing, University of Surrey, Guildford, United Kingdom
| |
Collapse
|
7
|
Farke D, Staszyk C, Failing K, Kirberger RM, Schmidt MJ. Sensitivity and specificity of magnetic resonance imaging and computed tomography for the determination of the developmental state of cranial sutures and synchondroses in the dog. BMC Vet Res 2019; 15:221. [PMID: 31262279 PMCID: PMC6604170 DOI: 10.1186/s12917-019-1967-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 06/17/2019] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND During skull ontogenesis, growth centers in the skull base and calvarial bones allow gradual expansion of the cranial vault. Premature growth termination of cranial base synchondroses and/or calvarial sutures can result in devastating skull dysmorphologies. There is evidence to believe that a premature closure in one or more cranial growth centers contribute to the brachycephalic skull morphology in dogs. To provide a proof of concept for the non-invasive investigation of ontogenetic changes in cranial sutures and synchondroses in living dogs, we compared magnet resonance imaging (MRI) and computed tomography (CT) with histologic findings. Our aim was to determine the in vitro sensitivity and specificity for conventional clinical imaging methods in the assessment of cranial suture closure and synchondroses ossification in dogs. RESULTS The evaluation of cranial base synchondroses in MRI had a sensitivity of up to 93.1% and a specificity of 72.7% dependent on the observer. The evaluation of cranial base synchondroses in CT had a sensitivity of 92.2% and a specificity of 86.4%. Suture assessment on MRI suture assessment had a sensitivity of 82.1% dependent on the observer and a specificity of 19.3%. CT suture assessment had a sensitivity of 85.1% and a specificity of 40.4% in dependence of the observer. CONCLUSION Conventional cross-sectional imaging techniques (MRI and CT) allow reliable assessment of the open or closed state of synchondroses within the cranial base. In contrast CT and MRI are not suitable for a reliable assessment of the cranial sutures in dogs.
Collapse
Affiliation(s)
- Daniela Farke
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University, Frankfurter Strasse 108, 35392 Giessen, Germany
| | - Carsten Staszyk
- Institute of Veterinary-Anatomy, -Histology, and –Embryology, Justus-Liebig-University, Frankfurter Strasse 98, 35392 Giessen, Germany
| | - Klaus Failing
- Department of Biomathematics, Justus-Liebig-University, Frankfurter Strasse 95, 35392 Giessen, Germany
| | - Robert M. Kirberger
- Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria, 0110 South Africa
| | - Martin J. Schmidt
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University, Frankfurter Strasse 108, 35392 Giessen, Germany
| |
Collapse
|
8
|
Cine balanced fast field echo magnetic resonance imaging of canine spinal arachnoid diverticulae pulsation. Vet J 2019; 248:86-90. [PMID: 31113570 DOI: 10.1016/j.tvjl.2019.04.014] [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: 07/27/2018] [Revised: 04/26/2019] [Accepted: 04/29/2019] [Indexed: 11/24/2022]
Abstract
Canine spinal arachnoid diverticulae (SAD) are characterised by focal cerebrospinal fluid dilatations within the subarachnoid space, most commonly associated with nonpainful paresis and ataxia secondary to chronic compressive myelopathy. Numerous imaging techniques have been described for diagnosis of this condition, including myelography, computed tomography myelography, and magnetic resonance imaging (MRI). The present retrospective study investigated the utility of cine balanced fast field echo (cine bFFE) MRI sequences in measuring pulsatile flow in 12 dogs with SAD. The secondary aim was to determine the prevalence and location of syringes in relation to SAD, as the co-occurrence of these conditions has not been previously reported. The degree of SAD pulsation was calculated as the change in area per cardiac cycle on sagittal (n = 12/12) and transverse (n = 7/12) cardiac-gated cine bFFE MRI sequences. Pulsation was identified on all sequences, with a median ratio of change in SAD area of 0.14 (range, 0.10-0.27; n = 12) on sagittal cine bFFE and 0.23 (range, 0.05-0.53; n = 7) on transverse cine bFFE sequences. Significant differences between minimum and maximum SAD dimensions were identified on sagittal (P = 0.002) and transverse measurements (P = 0.018). A moderate prevalence of syringomyelia was identified (n = 6/12; 50%) on T2W sequences, occurring both cranial (n = 4/12; 33%) and caudal (n = 2/12; 17%) to the SAD. These results support the ability of cine bFFE sequences to identify dynamic pulsation of canine SAD. This technique is currently limited by banding artifacts and its inability to quantify flow velocity and abnormal flow jets.
Collapse
|
9
|
Knowler SP, Gillstedt L, Mitchell TJ, Jovanovik J, Volk HA, Rusbridge C. Pilot study of head conformation changes over time in the Cavalier King Charles spaniel breed. Vet Rec 2019; 184:122. [PMID: 30635451 PMCID: PMC6589453 DOI: 10.1136/vr.105135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 11/23/2018] [Accepted: 11/23/2018] [Indexed: 11/23/2022]
Abstract
Modern interpretation of head conformation in the Cavalier King Charles spaniel (CKCS) has favoured a smaller, more exaggerated, brachycephalic type than originally described in the 1929 breed standard. Recent research studies identified brachycephaly and reduced hind cranium as two conformational (dysmorphic) features that increase risk for symptomatic Chiari-like malformation and secondary syringomyelia (SM). A prospective pilot study investigated the hypothesis that dysmorphic head features could be assessed visually and correlated with risk of SM. Thirteen CKCS, selected from anonymised photographic evidence, were physically appraised by authorised Kennel Club judges using a head shape checklist. These subjective evaluations were then matched with objective measurements of the cranium (cephalic index and rostrocaudal doming) and their subsequent MRI. A positive correlation (P=0.039) between the judges’ checklist score and rostrocaudal doming (hindskull ratio) and a positive correlation between the cephalic index and hindskull ratio (P=0.042) were identified. Five CKCS had no SM and their status tallied with 62 per cent of the judges’ evaluation. Although the ability of adjudicators to identify differences in head conformation varied, there was sufficient association between the dysmorphic parameters and the risk of SM to cause concern and propose a larger study in CKCS breed.
Collapse
Affiliation(s)
- Susan Penelope Knowler
- Faculty of Health and Medical Sciences, School of Veterinary Medicine, University of Surrey, Guildford, UK
| | | | | | | | - Holger Andreas Volk
- Department of Clinical Science and Services, Royal Veterinary College, Hatfield, UK
| | - Clare Rusbridge
- Faculty of Health and Medical Sciences, School of Veterinary Medicine, University of Surrey, Guildford, UK.,Neurology Department, Fitzpatrick Referrals, Godalming, UK
| |
Collapse
|
10
|
Rusbridge C, Stringer F, Knowler SP. Clinical Application of Diagnostic Imaging of Chiari-Like Malformation and Syringomyelia. Front Vet Sci 2018; 5:280. [PMID: 30547039 PMCID: PMC6279941 DOI: 10.3389/fvets.2018.00280] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Accepted: 10/22/2018] [Indexed: 12/18/2022] Open
Abstract
Chiari-like malformation (CM) and syringomyelia (SM) is a frequent diagnosis in predisposed brachycephalic toy breeds since increased availability of MRI. However, the relevance of that MRI diagnosis has been questioned as CM, defined as identification of a cerebellar herniation, is ubiquitous in some breeds and SM can be asymptomatic. This article reviews the current knowledge of neuroanatomical changes in symptomatic CM and SM and diagnostic imaging modalities used for the clinical diagnosis of CM-pain or myelopathy related to SM. Although often compared to Chiari type I malformation in humans, canine CM-pain and SM is more comparable to complex craniosynostosis syndromes (i.e., premature fusion of multiple skull sutures) characterized by a short skull (cranial) base, rostrotentorial crowding with rostral forebrain flattening, small, and ventrally orientated olfactory bulbs, displacement of the neural tissue to give increased height of the cranium and further reduction of the functional caudotentorial space with hindbrain herniation. MRI may further reveal changes suggesting raised intracranial pressure such as loss of sulci definition in conjunction with ventriculomegaly. In addition to these brachycephalic changes, dogs with SM are more likely to have craniocervical junction abnormalities including rostral displacement of the axis and atlas with increased odontoid angulation causing craniospinal junction deformation and medulla oblongata elevation. Symptomatic SM is diagnosed on the basis of signs of myelopathy and presence of a large syrinx that is consistent with the neuro-localization. The imaging protocol should establish the longitudinal and transverse extent of the spinal cord involvement by the syrinx. Phantom scratching and cervicotorticollis are associated with large mid-cervical syringes that extend to the superficial dorsal horn. If the cause of CSF channel disruption and syringomyelia is not revealed by anatomical MRI then other imaging modalities may be appropriate with radiography or CT for any associated vertebral abnormalities.
Collapse
Affiliation(s)
- Clare Rusbridge
- Fitzpatrick Referrals, Godalming, United Kingdom.,School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, United Kingdom
| | | | - Susan P Knowler
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, United Kingdom
| |
Collapse
|
11
|
Gordon CR, Marchant TW, Lodzinska J, Schoenebeck JJ, Schwarz T. Morphological variation of the caudal fossa of domestic cat skulls assessed with CT and geometric morphometrics analysis. J Feline Med Surg 2018; 20:752-758. [PMID: 28925790 PMCID: PMC11104145 DOI: 10.1177/1098612x17730707] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2024]
Abstract
Objectives This study aimed to investigate differences and demonstrate a normal range of morphological variation of the caudal fossa of the cranium of domestic cats. Methods CT scans of 32 domestic cat heads of 11 breeds were included. Isosurfaces from skulls were characterised through three-dimensional geometric morphometrics using geographical landmarks placed on the internal surface of the caudal fossa and foramen magnum. Raw data was transformed with a Procrustes fit and coordinate covariance was analysed by principal components to establish breed- and sex-level differences. Skulls were also classified according to the number of concavities along the mid-sagittal vermiform impression. Differences were investigated between breed groups and sex, and correlation was sought with age. Results Analyses revealed size-independent differences in occipital bone morphology across breeds and sex; however, no clustering was evident. Most variability was observed at the exoccipital bones, ventral portion of the supraoccipital bone, dorsum sellae of the basisphenoid and the osseous tentorium cerebelli. No statistically significant differences were identified via two-sample t-tests between breed groups or sexes. No statistically significant correlation using Spearman rho correlation coefficient was identified with age. Conclusions and relevance The feline caudal fossa displays a wide range of intra- and inter-breed variation, not linked to age or sex. Concavities along the vermiform impression have not previously been described. As advanced imaging modalities are becoming more frequently used for domestic felids, an established range of normality is important for discriminating pathological changes from anatomical variances.
Collapse
Affiliation(s)
- Caroline R Gordon
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, UK
| | | | - Joanna Lodzinska
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, UK
| | | | - Tobias Schwarz
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, UK
| |
Collapse
|
12
|
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.
Collapse
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
| |
Collapse
|
13
|
Ancot F, Lemay P, Knowler SP, Kennedy K, Griffiths S, Cherubini GB, Sykes J, Mandigers PJJ, Rouleau GA, Rusbridge C, Kibar Z. A genome-wide association study identifies candidate loci associated to syringomyelia secondary to Chiari-like malformation in Cavalier King Charles Spaniels. BMC Genet 2018; 19:16. [PMID: 29566674 PMCID: PMC5865342 DOI: 10.1186/s12863-018-0605-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 03/15/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Syringomyelia (SM) is a common condition affecting brachycephalic toy breed dogs and is characterized by the development of fluid-filled cavities within the spinal cord. It is often concurrent with a complex developmental malformation of the skull and craniocervical vertebrae called Chiari-like malformation (CM) characterized by a conformational change and overcrowding of the brain and cervical spinal cord particularly at the craniocervical junction. CM and SM have a polygenic mode of inheritance with variable penetrance. RESULTS We identified six cranial T1-weighted sagittal MRI measurements that were associated to maximum transverse diameter of the syrinx cavity. Increased syrinx transverse diameter has been correlated previously with increased likelihood of behavioral signs of pain. We next conducted a whole genome association study of these traits in 65 Cavalier King Charles Spaniel (CKCS) dogs (33 controls, 32 with extreme phenotypes). Two loci on CFA22 and CFA26 were found to be significantly associated to two traits associated with a reduced volume and altered orientation of the caudal cranial fossa. Their reconstructed haplotypes defined two associated regions that harbor only two genes: PCDH17 on CFA22 and ZWINT on CFA26. PCDH17 codes for a cell adhesion molecule expressed specifically in the brain and spinal cord. ZWINT plays a role in chromosome segregation and its expression is increased with the onset of neuropathic pain. Targeted genomic sequencing of these regions identified respectively 37 and 339 SNPs with significantly associated P values. Genotyping of tagSNPs selected from these 2 candidate loci in an extended cohort of 461 CKCS (187 unaffected, 274 SM affected) identified 2 SNPs on CFA22 that were significantly associated to SM strengthening the candidacy of this locus in SM development. CONCLUSIONS We identified 2 loci on CFA22 and CFA26 that contained only 2 genes, PCDH17 and ZWINT, significantly associated to two traits associated with syrinx transverse diameter. The locus on CFA22 was significantly associated to SM secondary to CM in the CKCS dog breed strengthening its candidacy for this disease. This study will provide an entry point for identification of the genetic factors predisposing to this condition and its underlying pathogenic mechanisms.
Collapse
Affiliation(s)
- Frédéric Ancot
- Department of Neurosciences, CHU Sainte Justine Research Center, University of Montréal, 3175 Cote-Sainte-Catherine, Room 3.17.006, Montreal, QC, H3T 1C5, Canada
| | - Philippe Lemay
- Department of Neurosciences, CHU Sainte Justine Research Center, University of Montréal, 3175 Cote-Sainte-Catherine, Room 3.17.006, Montreal, QC, H3T 1C5, Canada
| | - Susan P Knowler
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, Surrey, GU2 7AL, UK
| | - Karen Kennedy
- Department of Medical Imaging, London Health Sciences Centre, London, ON, N6A 5A5, Canada
| | - Sandra Griffiths
- Stone Lion Veterinary Hospital, 42 High Street, Wimbledon, SW19 5AU, UK
| | | | - Jane Sykes
- Thames Valley Veterinary Services, London, ON, N6A 4V2, Canada
| | - Paul J J Mandigers
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, 3584, CM, The Netherlands
| | - Guy A Rouleau
- Montreal Neurological Institute and McGill University, Montreal, QC, H3A 2B4, Canada
| | - Clare Rusbridge
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, Surrey, GU2 7AL, UK.,Fitzpatrick Referrals, Godalming, Surrey, GU7 2QQ, UK
| | - Zoha Kibar
- Department of Neurosciences, CHU Sainte Justine Research Center, University of Montréal, 3175 Cote-Sainte-Catherine, Room 3.17.006, Montreal, QC, H3T 1C5, Canada.
| |
Collapse
|
14
|
Hechler AC, Moore SA. Understanding and Treating Chiari-like Malformation and Syringomyelia in Dogs. Top Companion Anim Med 2018; 33:1-11. [DOI: 10.1053/j.tcam.2018.03.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/13/2018] [Accepted: 03/13/2018] [Indexed: 11/11/2022]
|
15
|
Wijnrocx K, Van Bruggen LWL, Eggelmeijer W, Noorman E, Jacques A, Buys N, Janssens S, Mandigers PJJ. Twelve years of chiari-like malformation and syringomyelia scanning in Cavalier King Charles Spaniels in the Netherlands: Towards a more precise phenotype. PLoS One 2017; 12:e0184893. [PMID: 28934242 PMCID: PMC5608246 DOI: 10.1371/journal.pone.0184893] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 09/03/2017] [Indexed: 11/18/2022] Open
Abstract
Chiari-like malformation (CM), syringomyelia (SM) and middle ear effusion (also called PSOM) are three conditions that frequently occur in Cavalier King Charles Spaniels (CKCS). Both CM and SM are currently screened in the Netherlands prior to breeding and are graded according to the British Veterinary Association's Kennel Club (BVA/KC) scheme. This study evaluated the prevalence and estimated genetic parameter of CM, SM and middle ear effusion from 12 years of screening results. For SM, the classical method using the BVA/KC scheme, was compared with exact measuring of the central canal dilation. For CM, the BVA/KC scheme was compared with a more detailed scheme. Next to this the presence of microchip artifacts was assessed. 1249 screening of 1020 dogs were re-evaluated. Results indicated the presence of CM in all dogs, suggesting it has become a breed-specific characteristic. And although different grades of CM were observed, the condition did not deteriorate over time. SM was present in 39% of the dogs and a clear age effect was demonstrated, with SM increasing with age. This emphasizes the importance of screening at appropriate age, since SM can worsen with increasing age. One alternative is to promote repeated measures. The presence of middle ear effusion in this study was 19%-21% for dogs younger than 3 years, and 32%-38% for dogs older than 3 years. In as much as 60%, microchip artifacts were noticed, leading to the recommendation to place microchips in another location in breeds that are susceptible to developing SM. Finally, this study estimated the heritability of CM in this population, due to the lack of phenotypic variance, to be very low at 0.02-0.03. The heritability for SM central canal dilatation to be 0.30, compared to 0.13 for the classical BVA/KC method, using a model including the age effect and the combined effect of veterinary clinic and year of the evaluation. Genetic correlations were rather small, ranging from 0.16-0.33. As a conclusion, screening for SM and CM in the entire population should be maintained, and a selection scheme against SM should be based on estimated breeding values for the exact measurement of the central canal dilatation.
Collapse
Affiliation(s)
- Katrien Wijnrocx
- KU Leuven Department of Biosystems, Livestock Genetics, Leuven, Belgium
| | - Leonie W. L. Van Bruggen
- University of Utrecht, Department of Clinical Sciences of Companion Animals, Utrecht, The Netherlands
| | - Wieteke Eggelmeijer
- University of Utrecht, Department of Clinical Sciences of Companion Animals, Utrecht, The Netherlands
| | | | | | - Nadine Buys
- KU Leuven Department of Biosystems, Livestock Genetics, Leuven, Belgium
| | - Steven Janssens
- KU Leuven Department of Biosystems, Livestock Genetics, Leuven, Belgium
| | - Paul J. J. Mandigers
- University of Utrecht, Department of Clinical Sciences of Companion Animals, Utrecht, The Netherlands
| |
Collapse
|
16
|
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.
Collapse
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
| |
Collapse
|
17
|
Use of Morphometric Mapping to Characterise Symptomatic Chiari-Like Malformation, Secondary Syringomyelia and Associated Brachycephaly in the Cavalier King Charles Spaniel. PLoS One 2017; 12:e0170315. [PMID: 28122014 PMCID: PMC5266281 DOI: 10.1371/journal.pone.0170315] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 01/02/2017] [Indexed: 11/19/2022] Open
Abstract
Objectives To characterise the symptomatic phenotype of Chiari-like malformation (CM), secondary syringomyelia (SM) and brachycephaly in the Cavalier King Charles Spaniel using morphometric measurements on mid-sagittal Magnetic Resonance images (MRI) of the brain and craniocervical junction. Methods This retrospective study, based on a previous quantitative analysis in the Griffon Bruxellois (GB), used 24 measurements taken on 130 T1-weighted MRI of hindbrain and cervical region. Associated brachycephaly was estimated using 26 measurements, including rostral forebrain flattening and olfactory lobe rotation, on 72 T2-weighted MRI of the whole brain. Both study cohorts were divided into three groups; Control, CM pain and SM and their morphometries compared with each other. Results Fourteen significant traits were identified in the hindbrain study and nine traits in the whole brain study, six of which were similar to the GB and suggest a common aetiology. The Control cohort had the most elliptical brain (p = 0.010), least olfactory bulb rotation (p = 0.003) and a protective angle (p = 0.004) compared to the other groups. The CM pain cohort had the greatest rostral forebrain flattening (p = 0.007), shortest basioccipital (p = 0.019), but a greater distance between the atlas and basioccipital (p = 0.002) which was protective for SM. The SM cohort had two conformation anomalies depending on the severity of craniocervical junction incongruities; i) the proximity of the dens (p <0.001) ii) increased airorhynchy with a smaller, more ventrally rotated olfactory bulb (p <0.001). Both generated ‘concertina’ flexures of the brain and craniocervical junction. Conclusion Morphometric mapping provides a diagnostic tool for quantifying symptomatic CM, secondary SM and their relationship with brachycephaly. It is hypothesized that CM pain is associated with increased brachycephaly and SM can result from different combinations of abnormalities of the forebrain, caudal fossa and craniocervical junction which compromise the neural parenchyma and impede cerebrospinal fluid flow.
Collapse
|
18
|
Knowler SP, Kiviranta AM, McFadyen AK, Jokinen TS, La Ragione RM, Rusbridge C. Craniometric Analysis of the Hindbrain and Craniocervical Junction of Chihuahua, Affenpinscher and Cavalier King Charles Spaniel Dogs With and Without Syringomyelia Secondary to Chiari-Like Malformation. PLoS One 2017; 12:e0169898. [PMID: 28121988 PMCID: PMC5266279 DOI: 10.1371/journal.pone.0169898] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 12/23/2016] [Indexed: 01/25/2023] Open
Abstract
OBJECTIVES To characterize and compare the phenotypic variables of the hindbrain and craniocervical junction associated with syringomyelia (SM) in the Chihuahua, Affenpinscher and Cavalier King Charles Spaniel (CKCS). METHOD Analysis of 273 T1-weighted mid-sagittal DICOM sequences of the hindbrain and craniocervical junction from 99 Chihuahuas, 42 Affenpinschers and 132 CKCSs. The study compared 22 morphometric features (11 lines, eight angles and three ratios) of dogs with and without SM using refined techniques based on previous studies of the Griffon Bruxellois (GB) using Discriminant Function Analysis and ANOVA with post-hoc corrections. RESULTS The analysis identified 14/22 significant traits for SM in the three dog breeds, five of which were identical to those reported for the GB and suggest inclusion of a common aetiology. One ratio, caudal fossa height to the length of the skull base extended to an imaginary point of alignment between the atlas and supraoccipital bones, was common to all three breeds (p values 0.029 to <0.001). Associated with SM were a reduced occipital crest and two acute changes in angulation i) 'sphenoid flexure' at the spheno-occipital synchondrosis ii) 'cervical flexure' at the foramen magnum allied with medulla oblongata elevation. Comparing dogs with and without SM, each breed had a unique trait: Chihuahua had a smaller angle between the dens, atlas and basioccipital bone (p value < 0.001); Affenpinschers had a smaller distance from atlas to dens (p value 0.009); CKCS had a shorter distance between the spheno-occipital synchondrosis and atlas (p value 0.007). CONCLUSION The selected morphometries successfully characterised conformational changes in the brain and craniocervical junction that might form the basis of a diagnostic tool for all breeds. The severity of SM involved a spectrum of abnormalities, incurred by changes in both angulation and size that could alter neural parenchyma compliance and/or impede cerebrospinal fluid channels.
Collapse
Affiliation(s)
- Susan P. Knowler
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, Surrey, United Kingdom
| | - Anna-Mariam Kiviranta
- Department of Equine and Small Animal Medicine, 00014 University of Helsinki, Finland
| | | | - Tarja S. Jokinen
- Department of Equine and Small Animal Medicine, 00014 University of Helsinki, Finland
| | - Roberto M. La Ragione
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, Surrey, United Kingdom
| | - Clare Rusbridge
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, Surrey, United Kingdom
- Fitzpatrick Referrals, Godalming, Surrey, United Kingdom
| |
Collapse
|
19
|
Miller MA, Zachary JF. Mechanisms and Morphology of Cellular Injury, Adaptation, and Death 1. PATHOLOGIC BASIS OF VETERINARY DISEASE 2017. [PMCID: PMC7171462 DOI: 10.1016/b978-0-323-35775-3.00001-1] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
20
|
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.
Collapse
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
| | | |
Collapse
|
21
|
Knowler SP, v/d Berg H, McFadyen A, La Ragione RM, Rusbridge C. Inheritance of Chiari-Like Malformation: Can a Mixed Breeding Reduce the Risk of Syringomyelia? PLoS One 2016; 11:e0151280. [PMID: 27008271 PMCID: PMC4805231 DOI: 10.1371/journal.pone.0151280] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 02/25/2016] [Indexed: 12/05/2022] Open
Abstract
Canine Chiari-like malformation (CM) is a complex abnormality of the skull and craniocervical junction associated with miniaturization and brachycephaly which can result in the spinal cord disease syringomyelia (SM). This study investigated the inheritance of CM in a Griffon Bruxellois (GB) family and feasibility of crossbreeding a brachycephalic CM affected GB with a mesaticephalic normal Australian terrier and then backcrossing to produce individuals free of the malformation and regain GB breed characteristics. The study family cohort (n = 27) included five founder dogs from a previous baseline study of 155 GB which defined CM as a global malformation of the cranium and craniocervical junction with a shortened skull base and increased proximity of the cervical vertebrae to the skull. T1-weighted sagittal DICOM images of the brain and craniocervical junction were analysed for five significant traits (two angles, three lines) identified from the previous study and subsequent Qualitative Trait Loci analysis. Mean measurements for mixed breed, pure-breed and baseline study groups were compared. Results indicated that mixed breed traits posed less risk for CM and SM and were useful to distinguish the phenotype. Moreover on the MR images, the filial relationships displayed by the traits exhibited segregation and those presenting the greatest risk for CM appeared additive towards the severity of the condition. The external phenotypes revealed that by outcrossing breed types and with careful selection of appropriate conformation characteristics in the first generation, it is possible to regain the GB breed standard and reduce the degree of CM. The four GB affected with SM in the study all exhibited reduced caudal skull development compared to their relatives. The craniocervical traits may be useful for quantifying CM and assessing the possibility of SM thus assisting breeders with mate selection. However, such a system requires validation to ensure appropriateness for all breeds at risk.
Collapse
Affiliation(s)
- Susan P. Knowler
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, Surrey, United Kingdom
| | - Henny v/d Berg
- Fitzpatrick Referrals, Eashing, Godalming, Surrey, United Kingdom
| | | | - Roberto M. La Ragione
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, Surrey, United Kingdom
| | - Clare Rusbridge
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, Surrey, United Kingdom
- Fitzpatrick Referrals, Eashing, Godalming, Surrey, United Kingdom
| |
Collapse
|
22
|
Rusbridge C, Long S, Jovanovik J, Milne M, Berendt M, Bhatti SFM, De Risio L, Farqhuar RG, Fischer A, Matiasek K, Muñana K, Patterson EE, Pakozdy A, Penderis J, Platt S, Podell M, Potschka H, Stein VM, Tipold A, Volk HA. International Veterinary Epilepsy Task Force recommendations for a veterinary epilepsy-specific MRI protocol. BMC Vet Res 2015; 11:194. [PMID: 26319136 PMCID: PMC4594743 DOI: 10.1186/s12917-015-0466-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 06/29/2015] [Indexed: 12/17/2022] Open
Abstract
Epilepsy is one of the most common chronic neurological diseases in veterinary practice. Magnetic resonance imaging (MRI) is regarded as an important diagnostic test to reach the diagnosis of idiopathic epilepsy. However, given that the diagnosis requires the exclusion of other differentials for seizures, the parameters for MRI examination should allow the detection of subtle lesions which may not be obvious with existing techniques. In addition, there are several differentials for idiopathic epilepsy in humans, for example some focal cortical dysplasias, which may only apparent with special sequences, imaging planes and/or particular techniques used in performing the MRI scan. As a result, there is a need to standardize MRI examination in veterinary patients with techniques that reliably diagnose subtle lesions, identify post-seizure changes, and which will allow for future identification of underlying causes of seizures not yet apparent in the veterinary literature. There is a need for a standardized veterinary epilepsy-specific MRI protocol which will facilitate more detailed examination of areas susceptible to generating and perpetuating seizures, is cost efficient, simple to perform and can be adapted for both low and high field scanners. Standardisation of imaging will improve clinical communication and uniformity of case definition between research studies. A 6–7 sequence epilepsy-specific MRI protocol for veterinary patients is proposed and further advanced MR and functional imaging is reviewed.
Collapse
Affiliation(s)
- Clare Rusbridge
- Fitzpatrick Referrals, Halfway Lane, Eashing, Godalming, GU7 2QQ, Surrey, UK. .,School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, GU2 7TE, Surrey, UK.
| | - Sam Long
- University of Melbourne, 250 Princes Highway, Weibee, 3015, VIC, Australia.
| | - Jelena Jovanovik
- Fitzpatrick Referrals, Halfway Lane, Eashing, Godalming, GU7 2QQ, Surrey, UK.
| | - Marjorie Milne
- University of Melbourne, 250 Princes Highway, Weibee, 3015, VIC, Australia.
| | - Mette Berendt
- Department of Veterinary and Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark.
| | - Sofie F M Bhatti
- Department of Small Animal Medicine and Clinical Biology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium.
| | - Luisa De Risio
- Animal Health Trust, Lanwades Park, Kentford, Newmarket, CB8 7UU, Suffolk, UK.
| | - Robyn G Farqhuar
- Fernside Veterinary Centre, 205 Shenley Road, Borehamwood, SG9 0TH, Hertfordshire, UK.
| | - Andrea Fischer
- Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University, Veterinärstr. 13, 80539, Munich, Germany.
| | - Kaspar Matiasek
- Section of Clinical & Comparative Neuropathology, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University, Veterinärstr. 13, 80539, Munich, Germany.
| | - Karen Muñana
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 1052 William Moore Drive, Raleigh, NC, 27607, USA.
| | - Edward E Patterson
- University of Minnesota College of Veterinary Medicine, D426 Veterinary Medical Center, 1352 Boyd Avenue, St. Paul, MN, 55108, USA.
| | - Akos Pakozdy
- Clinical Unit of Internal Medicine Small Animals, University of Veterinary Medicine, Veterinärplatz 1, 1210, Vienna, Austria.
| | - Jacques Penderis
- Vet Extra Neurology, Broadleys Veterinary Hospital, Craig Leith Road, Stirling, FK7 7LE, Stirlingshire, UK.
| | - Simon Platt
- College of Veterinary Medicine, University of Georgia, 501 DW Brooks Drive, Athens, GA, 30602, USA.
| | - Michael Podell
- Chicago Veterinary Neurology and Neurosurgery, 3123 N. Clybourn Avenue, Chicago, IL, 60618, USA.
| | - Heidrun Potschka
- Department of Pharmacology, Toxicology and Pharmacy, Ludwig-Maximillians-University, Königinstr. 16, 80539, Munich, Germany.
| | - Veronika M Stein
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Bünteweg 9, 30559, Hannover, Germany.
| | - Andrea Tipold
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Bünteweg 9, 30559, Hannover, Germany.
| | - Holger A Volk
- Department of Clinical Science and Services, Royal Veterinary College, Hatfield, AL9 7TA, Hertfordshire, UK.
| |
Collapse
|
23
|
Mitchell TJ, Knowler SP, van den Berg H, Sykes J, Rusbridge C. Syringomyelia: determining risk and protective factors in the conformation of the Cavalier King Charles Spaniel dog. Canine Genet Epidemiol 2014; 1:9. [PMID: 26401326 PMCID: PMC4579371 DOI: 10.1186/2052-6687-1-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 07/18/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Syringomyelia (SM) is a painful neurological condition, prevalent in brachycephalic toy breeds including the Cavalier King Charles Spaniel (CKCS). In these breeds, SM is typically secondary to Chiari-like Malformation (CM). There has been much debate in the scientific and veterinary communities to what extent head shape is indicative of either pathology, especially as certain craniosynostosis syndromes in humans (highly associated with CM) have characteristic facial and cranial morphologies. Elucidating a risk morphology would allow for selection away from these traits and proffer further breeding guidelines for the condition. Dogs were measured in multiple countries by means of a standardised bony landmark measuring protocol and photo analysis by blinded, trained researchers. RESULTS The results found two significant risk factors in the conformation of the CKCS: extent of brachycephaly and distribution of cranium. The study identified a greater amount of cranium distributed caudally (relative to the amount distributed rostrally) to be significantly protective against syrinx development at the levels of three years of age, five years of age and when comparing a sample of SM clear individuals over the age of five to those affected younger than three years of age. A decreased cephalic index (decreasing brachycephaly) was significantly protective at the latter level. Cephalic index and caudal cranium distribution exhibited a negative, linear relationship. Cephalic index demonstrated a positive linear relationship with the amount of doming of the head. CONCLUSIONS This study proposes a risk phenotype of brachycephaly with resulting rostrocaudal doming that is more rostrally distributed and hence sloping caudally. The results of this study may allow for selection against risk aspects of conformation in the CKCS in combination with the British Veterinary Association/Kennel Club CM/SM scheme to enable reduction in CM/SM incidence. Further research comparing this external risk phenotype to the internal presentation upon MRI would determine how these features are indicative of syrinx development. Utilising breeds in which CM free individuals are more available may allow for validation of this risk phenotype for CM or determine alternatives.
Collapse
Affiliation(s)
- Thomas J Mitchell
- School of Clinical Veterinary Science, University of Bristol, Langford, Bristol BS40 5DU UK
| | - Susan P Knowler
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Duke of Kent Building, Guildford, Surrey GU2 7TE UK
| | - Henny van den Berg
- Fitzpatrick Referrals, Halfway Lane, Eashing, Godalming, Surrey GU7 2QQ UK
| | - Jane Sykes
- Lawson Imaging, Lawson Health Research Institute, 268 Grosvenor Street, London, Ontario N6A 4V2 Canada
| | - Clare Rusbridge
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Duke of Kent Building, Guildford, Surrey GU2 7TE UK ; Fitzpatrick Referrals, Halfway Lane, Eashing, Godalming, Surrey GU7 2QQ UK
| |
Collapse
|