Comparison of ultrasonographic and computed tomographic imaging of equine thoracolumbar articular process joints.

BACKGROUND: Osteoarthritis of the equine thoracolumbar articular process joints (APJs) has been linked to back pain. Changes are commonly diagnosed through nuclear scintigraphy, radiography and ultrasonography (US). OBJECTIVES: (1) To assess the agreement of APJ grades between US and computed tomography (CT) images; (2) to assess the effect of location on the agreement of APJ grades between US and CT images. It was hypothesised that: (1) Periarticular modelling and modification of the joint space would have the highest and lowest agreement between US and CT images, respectively; (2) Caudal thoracolumbar APJ grades would have higher agreement between US and CT images than mid thoracic APJs. STUDY DESIGN: Comparative diagnostic imaging study using cadaveric specimens. METHODS: Disarticulated thoracolumbar spines of six equids euthanised for reasons unrelated to back pain, underwent US and CT examination of the APJs. Images were assessed for periarticular modelling, modification of the joint space and enlargement of the APJ. Intra-observer, inter-modality and inter-observer agreement using multilevel weighted kappa statistics to evaluate the effects of location, US/CT characteristic and their interaction. RESULTS: Intra-observer agreement of US and CT grades ranged from moderate to perfect. Between T15 and L1, inter-modality agreement (CT vs. US) for periarticular modelling was moderate, and fair for enlargement and modification of the joint space. Inter-observer agreement (US vs. US) of periarticular modelling was substantial between T15 and L1, moderate between L1 and L5 and fair between T10 and T15. Wide confidence intervals (CIs) seen for most grades apart from inter-observer grades of periarticular modelling at T15-L5, introducing a degree of uncertainty into the results. MAIN LIMITATIONS: Large prevalence index influenced kappa values, small sample size. CONCLUSIONS: Good inter-observer (US vs. US) and inter-modality (CT vs. US) agreement of caudal thoracolumbar APJ periarticular modelling. This US characteristic provides a measure of bone change, therefore supporting the use of diagnostic ultrasound. Inter-modality CIs were wide, highlighting the study and imaging modality limitations.

Aided Cortical Auditory Evoked Potentials in Infants With Frequency-Specific Synthetic Speech Stimuli: Sensitivity, Repeatability, and Feasibility.

OBJECTIVES: The cortical auditory evoked potential (CAEP) test is a candidate for supplementing clinical practice for infant hearing aid users and others who are not developmentally ready for behavioral testing. Sensitivity of the test for given sensation levels (SLs) has been reported to some degree, but further data are needed from large numbers of infants within the target age range, including repeat data where CAEPs were not detected initially. This study aims to assess sensitivity, repeatability, acceptability, and feasibility of CAEPs as a clinical measure of aided audibility in infants. DESIGN: One hundred and three infant hearing aid users were recruited from 53 pediatric audiology centers across the UK. Infants underwent aided CAEP testing at age 3 to 7 months to a mid-frequency (MF) and (mid-)high-frequency (HF) synthetic speech stimulus. CAEP testing was repeated within 7 days. When developmentally ready (aged 7-21 months), the infants underwent aided behavioral hearing testing using the same stimuli, to estimate the decibel (dB) SL (i.e., level above threshold) of those stimuli when presented at the CAEP test sessions. Percentage of CAEP detections for different dB SLs are reported using an objective detection method (Hotellings T 2 ). Acceptability was assessed using caregiver interviews and a questionnaire, and feasibility by recording test duration and completion rate. RESULTS: The overall sensitivity for a single CAEP test when the stimuli were ≥0 dB SL (i.e., audible) was 70% for the MF stimulus and 54% for the HF stimulus. After repeat testing, this increased to 84% and 72%, respectively. For SL >10 dB, the respective MF and HF test sensitivities were 80% and 60% for a single test, increasing to 94% and 79% for the two tests combined. Clinical feasibility was demonstrated by an excellent >99% completion rate, and acceptable median test duration of 24 minutes, including preparation time. Caregivers reported overall positive experiences of the test. CONCLUSIONS: By addressing the clinical need to provide data in the target age group at different SLs, we have demonstrated that aided CAEP testing can supplement existing clinical practice when infants with hearing loss are not developmentally ready for traditional behavioral assessment. Repeat testing is valuable to increase test sensitivity. For clinical application, it is important to be aware of CAEP response variability in this age group.

Gross, computed tomographic, and endoscopic anatomy of the equine carpal extensor tendon sheaths.

OBJECTIVE: (1) To describe the computed tomography (CT) and gross anatomy of the equine extensor carpi radialis sheath (ECRS) and common digital extensor sheath (CDETS); (2) to describe a single-portal endoscopic examination of the ECRS and CDETS. STUDY DESIGN: Ex vivo experimental. SAMPLE POPULATION: Thirty clinically normal cadaver thoracic equine limbs severed at the humeral diaphysis. METHODS: Ten limbs underwent plain and intrathecal contrast CT examinations and gross dissection of the ECRS and CDETS. Single-portal endoscopic examination of ECRS and CDETS was attempted in 4 limbs and endoscopic examination was performed on 16 limbs. Endoscopic video recordings were reviewed by 3 observers for quality of visualization before dissection and examination for iatrogenic damage. Interobserver agreement for ECRS and CDETS visualization was determined with Fleiss' κ agreement. RESULTS: Extensor carpi radialis sheath and CDETS anatomy was consistent between gross dissection and CT examinations. The ECRS endoscopic portal was medial at the level of the intersection between the extensor carpi obliquus and extensor carpi radialis tendon. The CDETS endoscopic portal was lateral, 5 cm proximal to the lateral styloid process of the ulna. The ECRS and CDETS were well visualized and interobserver agreement was substantial (κ = .73; P < .0001) and moderate (κ = .53; P < .0001), respectively. CONCLUSION: Computed tomography examinations provided useful anatomical information, consistent with gross dissection of the ECRS and CDETS. The described single-portal endoscopic techniques allowed consistent tenoscopic examination of the majority of the ECRS and CDETS. CLINICAL SIGNIFICANCE: Awareness of the intrathecal anatomy of the ECRS and CDETS should facilitate the treatment of these tendon sheaths. The proposed portals provide good to excellent single-site endoscopic visualization of the majority of the ECRS and CDETS.

Computed Tomographic Assessment of Individual Paranasal Sinus Compartment and Nasal Conchal Bulla Involvement in 300 Cases of Equine Sinonasal Disease.

Background: Computed tomographic (CT) imaging has allowed new anatomical studies and detailed clinical imaging of the complex, overlapping equine sinonasal structures. Despite the widespread use of CT, no study has specifically identified which compartments are most commonly affected with sinus disorders. CT has also shown the presence of intercurrent, ipsilateral nasal disorders, especially infection of the nasal conchal bullae (NCB) in many cases of sinus disease, but the frequency of intercurrent NCB infections has not been reported. Objectives: To identify which sinus compartments are most commonly affected in horses with clinical sinus disorders and to record the prevalence of NCB involvement in such cases. Study Design: Retrospective examination of CT images of horses with confirmed unilateral sinus disease. Methods: The CT images of 300 horses, from three different equine hospitals with clinically confirmed sinus disease [mainly dental (53%) and primary sinusitis (25.7%)] were retrospectively examined to determine which sinus compartments and NCBs were affected. Results: The rostral, more dependent sinus compartments were most commonly involved, i.e., the rostral maxillary sinus in 284/300 (94.7% affected) and the ventral conchal sinus (87% affected). The caudal maxillary sinus (65.3%), dorsal conchal sinus (52.7%), frontal sinus (26%), ethmoidal sinus (32%) and sphenopalatine sinus (28.7%) were less commonly affected. There was infection or destruction of the ipsilateral NCBs in 56% of horses with sinus disorders, including the ventral NCBs in 42.3%, dorsal NCBs in 29% and both NCBs in 18% of cases. Main Limitations: The horses with sinonasal disease that underwent head CT imaging include more problematic cases and horses of high value, rather than the general horse population. Conclusions: The more dependant (i.e., the RMS and VCS) sinus compartments are most commonly involved in sinus disorders, with the RMS involved in nearly every case. The more dorsally located sinuses (i.e., caudal group) are less commonly involved. Many horses with sinus disease also have disorders of their nasal conchal bullae and so the term sinonasal disease seems appropriate for these disorders.

Equine odontogenic tumors: Clinical presentation, CT findings, and outcome in 11 horses.

Odontogenic tumors present as locally invasive, slow growing, firm swellings on the face. They are rare in all species and are characterized histologically by the degree of differentiation and dental tissue of origin. Radiographic appearance is not pathognomonic for these lesions. Computed tomographic (CT) examination allows exact determination of tumor extension and aggressiveness. The objectives of this retrospective, case series study were to describe the clinical presentation, CT characteristics, and outcome in horses with histologically confirmed odontogenic tumors, and to identify imaging features suggestive of individual types of tumors. Four ameloblastomas, two ameloblastic carcinomas, three ameloblastic fibromas, and two complex odontomas were included. All but one complex odontoma presented as a single mass. All tumors were associated with maxillary or mandibular bone expansion, alveolar and cortical bone lysis, and cortical bone thinning. The majority also had cortical bone thickening and periosteal proliferation. All tumors contained some degree of mineral attenuation, although only the complex odontomas contained enamel attenuation allowing differentiation from other types of odontogenic tumors in this study. Ameloblastomas were found to have variable CT characteristics likely due to the sub-groups of ameloblastomas. Both ameloblastic carcinomas contained a mixture of mineralized and soft tissue attenuating material whereas ameloblastic fibromas were mainly composed of soft tissue attenuating material. Computed tomographic characteristics of odontogenic tumors generally indicate that they are expansile, aggressive tumors and can occur in a wide range of ages. Further investigation is needed to elucidate differences between each type of equine odontogenic tumor.

Interaction with macrophages attenuates equine fibroblast-like synoviocyte ADAMTS5 (aggrecanase-2) gene expression following inflammatory stimulation.

The joint synovium consists of a heterogeneous cell population, chiefly comprised of macrophages, and fibroblast-like synoviocytes (FLS). An inter-species co-culture model was developed to examine interactions between these cells. Equine FLS and the canine macrophage line DH82 were differentially labeled using fluorescent markers and results from direct co-culture compared with those from both indirect co-culture, and conditioned media experiments. The transcript expression of IL-1ß, IL-6, ADAMTS4, and ADAMTS5 in each cell type were determined using species-specific qPCR assays. Lipopolysaccharide stimulation of EFLS rapidly increased IL-1ß, IL-6, ADAMTS4, and ADAMTS5 mRNAs. The induction of ADAMTS5 was significantly reduced when equine FLS were cultured with DH82 cells directly or indirectly. Exposure of equine FLS to denatured conditioned media also significantly reduced ADAMTS5 induction. DH82 cells increased interleukin-1ß expression substantially following LPS stimulation. However, knockdown of interleukin-1ß in DH82 cells, or inhibition of NF-κB in equine FLS prior to co-culture did not change the inhibitory effect on equine FLS ADAMTS5 gene expression. This work indicates that macrophages can influence FLS gene expression through a soluble mediator, and modulate the expression of an enzyme critical in osteoarthritis pathology during inflammatory stimulation. © 2018 The Authors. Journal of Orthopaedic Research® Published by WileyPeriodicals, Inc. on behalf of the Orthopaedic Research Society. J Orthop Res 9999:1-8, 2018.