Computed tomographic features of the prostatic gland in neutered and intact dogs.

BACKGROUND: Aim was to investigate age-dependent changes in the prostate of castrated dogs in computed tomographic (CT) examination. Thirty-six canine prostates were evaluated in pre- and post-contrast CT scans. Dogs were divided in groups with homogenous prostatic tissue (25/36) and with tissue alterations (11/36). Prostatic attenuation in Hounsfield Units (HU) and prostatic size were measured and a ratio of the prostatic size to the sixth lumbar vertebra was calculated. Additionally, the CT images of the prostate were compared with ultrasound examination. RESULTS: In pre-contrast CT scans no significant differences were found in prostatic size between homogenous and altered prostatic tissue groups whereas prostatic attenuation differed significantly in post-contrast CT between these groups. The homogenous tissue pattern of homogeneous prostates could be confirmed in CT images and in ultrasound examination. Concerning prostates with alterations, the results differed between ultrasound and CT examination in four cases of 11 dogs with tissue alterations. CONCLUSIONS: CT is beneficial to examine the prostate of castrated dogs. The prostatic attenuation is characteristic for the prostatic morphology, which can vary due to ageing processes. Differences in attenuation and size can be found between prostates of castrated and intact dogs. Using contrast agent, CT can visualize prostatic alterations, which were not seen in ultrasound. The presented results should be considered preliminary until a study with larger sample size and histologic examination of the prostates is performed.

Comparative measurements of bone mineral density and bone contrast values in canine femora using dual-energy X-ray absorptiometry and conventional digital radiography.

BACKGROUND: Aseptic loosening due to bone remodelling processes after total hip replacement is one common cause for revision surgery. In human medicine, dual-energy X-ray absorptiometry (DEXA) is the gold standard for quantitative evaluation of bone mineral density, whereas in veterinary medicine conventional radiography is used for follow-up studies. Recently, a method has been described using digital X-ray images for quantitative assessment of grey scale values of bone contrast. Therefore, the aim of the present study was to evaluate the correlation of bone mineral density (BMD) measured by DEXA with grey scale values (GV) measured in digital X-ray images (RX50, RX66) ex vivo. RESULTS: The measured GV in the chosen X-ray settings showed on average a good correlation (r = 0.61) to the measured BMD with DEXA. Correlation between the two X-ray settings was very good (r = 0.81). For comparisons among regions of interests (ROIs) a difference of 8.2% was found to be statistically significant, whereas in the case of RX50 and RX66 differences of 5.3% and 4.1% were found to be statistically significant. CONCLUSIONS: Results indicate that measuring absolute changes in bone mineral density might be possible using digital radiography. Not all significant differences between ROIs detectable with DEXA can be displayed in the X-ray images because of the lower sensitivity of the radiographs. However, direct comparison of grey scale values of the periprosthetic femur in one individual patient during the follow-up period, in order to predict bone remodelling processes, should be possible, but with a lesser sensitivity than with DEXA. It is important that the same X-ray settings are chosen for each patient for follow-up studies.

Computed tomography: a beneficial diagnostic tool for the evaluation of the canine prostate?

BACKGROUND: Prostatic diseases in intact male dogs are common. However, studies about the computed tomographic (CT) examination of the prostate in dogs are rare. The aim of the present study was to evaluate age related-changes in the canine prostate with the help of the CT and to evaluate whether measuring Hounsfield Units (HUs) in different morphological conditions of the prostate is of diagnostic value. Fifty pre- and post-contrast CT scans of the prostate of dogs were evaluated and divided into three groups according to the tissue structure: Group1 dogs with homogenous prostate tissue (16/50); group 2 with prostate cysts (26/50) and group 3 with inhomogeneous prostate tissue (8/50). The prostatic dimensions were measured and the ratio between length, height and width and the sixth lumbar vertebra was calculated. Median values of prostatic attenuation measured in HUs, using regions of interests (ROIs) were determined on pre- and post- contrast scans over the whole length of the prostate. The results were compared to the dog's age. Furthermore, the CT Images were compared with the results of ultrasonography (47/50). RESULTS: On pre-contrast scans HUs within ROIs placed in the prostate did not differ statistically significantly between the different morphological groups (1: 37.7; 2: 36.3; 3: 39.8 HU). HUs within on the post- contrast scans showed statistically significant differences between the groups. Group one had a mean density of 93.6 HU, group two had a mean density of 106.1 HU and group three had one of 138.2 HU. The prostatic size in the first group was smaller than in the other groups, whereas the largest prostates were found in the second group. In six cases the post-contrast CT scan showed results that differed from the ultrasound examination. Dogs had a homogenous tissue in ultrasonography while the CT scan revealed an inhomogeneous tissue structure. CONCLUSIONS: The CT examination can be a beneficial diagnostic tool for examining the prostatic size and for evaluating the prostatic tissue. The different HUs reflected age-related changes and alterations in the prostate while measuring the density of the prostate. Contrast agent application enables a more specific analysis of the prostate to be carried out and for precise changes in tissue structure to be observed.

[Classification of canine intervertebral disc degeneration using high-field magnetic resonance imaging and computed tomography]. / Klassifikation der Bandscheibendegeneration des Hundes in der nativen Computertomographie und der Hochfeld-Magnetresonanztomographie.

OBJECTIVE: Although the classification of canine intervertebral disc degeneration using magnetic resonance imaging (MRI) has been described in the literature, there is no such classification using computed tomographic imaging. Because computed tomography (CT) is a frequently used diagnostic imaging tool in veterinary medicine, the aim of this study was the introduction and validation of such a scoring system. T2-weighted magnetic resonance images were available for comparative analysis. MATERIAL AND METHODS: A total of 43 dogs were examined using CT and MRI. Image data records of 144 intervertebral discs were blinded, randomized and evaluated twice by three observers. CT data were analyzed using a self-developed scoring system, while MRI data sets were evaluated using the Pfirrmann scoring system. Intra- and interobserver agreement were determined using Statistical Analysis Software (SAS). RESULTS: Intra- and interobserver agreement were mostly substantial in the Pfirrmann (0.58-0.77) and self-developed (0.60-0.81) scoring systems. A slight agreement was found between both classification systems (κ scores 0.26-0.29). CONCLUSION AND CLINICAL RELEVANCE: The self-developed scoring system allows a reliable assessment of canine intervertebral disc degeneration using CT imaging. Therefore, further diagnostic and prognostic information can be obtained. Degenerative changes in the intervertebral discs could be identified at an earlier stage when using MRI in comparison with CT.

[Deafness in the dog and cat: aetiology, diagnostics and treatment]. / Taubheit bei Hunden und Katzen: Ursachen, Diagnostik und Therapie.

Deafness is one of the most common sensory deficits in cats and dogs. Determining the scope and the cause of deafness is important for a possible therapy and can enable the handling of the animal by its owner as well as influence the decision about breeding with the affected animal. Electrodiagnostic testing using the brainstem auditory evoked response (BAER) enables an objective evaluation of the hearing function. Additionally, otoscopy and various diagnostic imaging techniques, including computed tomography, can help in determining the cause of deafness. While conductive deafness can often be treated, there is normally no satisfactory treatment for sensorineural deafness. In such cases, an important task of the attending veterinarian is to advise the owner on handling his/her animal.

[Use of gold implants as a treatment of pain related to canine hip dysplasia--a review. Part 2: Clinical trials and case reports]. / Anwendung von Goldimplantaten zur Schmerztherapie bei kaniner Hüftgelenkdysplasie--eine Literaturübersicht. Teil 2: Klinische Studien und Fallberichte.

Gold bead implantation/gold acupuncture is becoming increasingly used in veterinary medicine as a method of pain treatment in cases of osteoarthritic diseases. Part one of the overview dealing with the use of gold implants as a treatment of canine hip joint dysplasia (cHD) introduced the method of implanting gold in tissue and publications which investigated the subsequent effects of implantation. This article focuses on publications concerning the clinical effectiveness of gold implantation within the scope of pain therapy in cHD. Due to the study design, a classification using evidence-based levels (EbL) was carried out. Three double-blind, placebo-controlled randomised studies (EbL II) were considered together with three retrospective studies on own patients (EbL IV) and five case studies (EbL IV). While the case and retrospective studies reported impressive therapeutic success in treating cHD-incurred pain with gold implantation, a pain-reducing effect through gold implantation was only demonstrated in one of the three double-blind studies. The two remaining EbL II studies found no differences between the placebo-group and the group of dogs treated with gold implantation. In one of these two studies, kinematic and kinetic gait analyses were used for objective evaluation of the effects of the treatment. Thus, the only study that carried out an objective evaluation of the therapeutic result of gold implantation came to the conclusion that the method is ineffective. For a concluding assessment of gold implantation in the case of cHD, gait analysis studies investigating the effects of gold implantation in comparison to a standard treatment with nonsteroidal anti-inflammatory drugs are currently lacking.

[Use of gold implants as a treatment of pain related to canine hip dysplasia--a review. Part 1: Background and current state of research regarding the effects of implanting gold in tissue]. / Anwendung von Goldimplantaten zur Schmerztherapie bei kaniner Hüftgelenkdysplasie--eine Literaturübersicht. Teil 1: Hintergründe und Stand der Forschung zu Effekten nach Implantation von Gold in Gewebe.

Gold-bead implantation as a method of pain treatment in dogs suffering from osteoarthritic disease is receiving increasing attention in veterinary medicine. For the present article, publications from veterinary books and journals were collected and evaluated, together with related articles in human medicine. After providing an overview of the historical use of gold and gold compounds, the technique of implanting this noble metal is introduced. The reasons for establishing the terms gold acupuncture and gold (bead) implantation are described, considering the question whether and what kind of methodological differences exist behind these terms. Next, previous publications concerning the effects of gold implantation in tissue are summarised. In 2002 it was proven that gold ions are released from the surface of gold implants by a process termed dissolucytosis. Subsequent publications further investigated details about the interaction between gold ions and tissue as well as the distribution pattern of bio-released ions. Gold compounds were previously used for chrysotherapy in human medicine until medication with fewer side effects became established. The anti-inflammatory and immuno-modulatory properties of gold compounds were used to treat rheumatoid arthritis. Current research aims to ascertain whether the anti-inflammatory and immuno-modulating effects of gold compounds are imitated by gold ions released from gold implants at a local level. In conclusion, the present review summarises important findings about the effects of gold implanted in tissue. However, further research is necessary to estimate the limitations and benefits of this auromedication.

Owner-collected swabs of pets: a method fit for the purpose of zoonoses research.

As part of the preparation of a large cohort study in the entire German population, this study examined the feasibility of cat and dog owners collecting nasal and oral swabs of their animals at home as a method of assessing exposure to zoonoses. In veterinary clinics in Hannover, Germany, 100 pet owners were recruited. Nasal and oral swabs of pets were taken by a veterinarian at the clinic and owners took swabs at home. Swabs were analysed regarding bacterial growth and compared (owner vs. vet) using Cohen's kappa and McNemar's test. The return rate of kits was 92%, and 77% of owners thought it unnecessary to have veterinarian assistance to swab the mouth. McNemar's test results: oral swabs 78% agreement with Gram-positive bacterial growth, 87% agreement with Gram-negative bacterial growth; with similar results for nasal swabs. Although sample quality differed, this method allowed the receipt of swabs from pets in order to obtain information about colonization with zoonotic pathogens.

Computer-based gait analysis of dogs: evaluation of kinetic and kinematic parameters after cemented and cementless total hip replacement.

To date it is unclear whether cementless total hip replacement (THR) in dogs is of clinical advantage in comparison to cemented THR with regard to lameness improvement. Thus the aim of this study was to compare objectively the development of the gait pattern after cemented and cementless THR in dogs. For this purpose, 18 adult dogs with hip dysplasia underwent computer-based gait analysis on an instrumented treadmill prior to unilateral THR and then again ten days, four weeks and four months after surgery. Analysed kinetic parameters were symmetry indices (SI) of vertical ground reaction forces (GRF), which included peak vertical forces (PFz), mean vertical forces (MFz), vertical impulse (IFz), and vertical ground reaction forces of the arthroplasty limbs only. Analysed kinematic parameters were range-of-motion and the flexion and extension angles of hip, stifle and hock joints. The symmetry indice for PVF, MFz and IFz decreased to a value less than six in both THR groups four months after surgery, which is defined as not lame. Improvement in lameness of the arthroplasty limbs during the examination period of four months was not significantly different between the cemented and cementless groups. The results suggest that within a short-term observation period of four months after surgery, neither cementless nor cemented THR have a greater advantage with regard to lameness improvement. Additional studies with larger pools of subjects and longer time periods for follow-up examinations are necessary to verify these findings.

Effects of high-mobility group a protein application on canine adipose-derived mesenchymal stem cells in vitro.

Multipotency and self-renewal are considered as most important features of stem cells to persist throughout life in tissues. In this context, the role of HMGA proteins to influence proliferation of adipose-derived mesenchymal stem cell (ASCs) while maintaining their multipotent and self-renewal capacities has not yet been investigated. Therefore, extracellular HMGA1 and HMGA2 application alone (10-200 ng/mL) and in combination with each other (100, 200 ng/mL each) was investigated with regard to proliferative effects on canine ASCs (cASCs) after 48 hours of cultivation. Furthermore, mRNA expression of multipotency marker genes in unstimulated and HMGA2-stimulated cASCs (50, 100 ng/mL) was analyzed by RT-qPCR. HMGA1 significantly reduced cASCs proliferation in concentrations of 10-200 ng/mL culture medium. A combination of HMGA1 and HMGA2 protein (100 and 200 ng/mL each) caused the same effects, whereas no significant effect on cASCs proliferation was shown after HMGA2 protein application alone. RT-qPCR results showed that expression levels of marker genes including KLF4, SOX2, OCT4, HMGA2, and cMYC mRNAs were on the same level in both HMGA2-protein-stimulated and -unstimulated cASCs. Extracellular HMGA protein application might be valuable to control proliferation of cASCs in context with their employment in regenerative approaches without affecting their self-renewal and multipotency abilities.

[Computed tomography diagnosis of a retrobulbar abscess in a white tiger]. / Computertomographische Diagnostik eines retrobulbären Abszesses bei einem weißen Königstiger.

SUBJECT: Etiologic diagnosis of a retrobulbar process is essential for the initiation of a causative therapy. Penetrating foreign bodies and tooth root abscesses, but also neoplastic processes have to be considered as a differential diagnosis for a retrobulbar swelling. The objective of this case report of a tiger with a retrobulbar process was to demonstrate the diagnostic value of computed tomography for making a causative diagnosis. MATERIAL AND METHODS: General examination of the tiger as well as subsequent computed tomography and surgical extraction of a fractured fourth premolar tooth of the left upper jaw was carried out under general anaesthesia. Collected alveolar tissue samples underwent cytological, histopathological and microbiological analyses. RESULTS AND CLINICAL RELEVANCE: Computed tomography was able to allocate the origin of the retrobulbar abscess to the left 4th premolar tooth of the upper jaw. The cytological, histopathological and microbiological examination of the recovered alveolar material confirmed the diagnosis of purulent-necrotic abscess-forming inflammation as a result of a mixed bacterial infection. The present case report demonstrates the diagnostic accuracy of computed tomography for the diagnosis of a retrobulbar process of unknown origin.

In vivo MRI of intraspinally injected SPIO-labelled human CD34+ cells in a transgenic mouse model of ALS.

BACKGROUND/AIM: Administration of stem cells is a promising novel approach for treatment of neurodegenerative diseases. For in vivo monitoring of transplanted cells, non-invasive imaging modalities are needed. In this study we determined the tracking efficiency of a superparamagnetic iron oxide (SPIO)-labelled canine cell line (MTH53A) in vitro as well as the human CD34(+) umbilical cord blood stem cells (hUCBCs) in vitro and in vivo efficiency by magnetic resonance imaging (MRI). MATERIALS AND METHODS: SPIO-labelled MTH53A cells and hUCBCs were scanned in agar gel phantoms at 1.0 T or 7.0 T. For in vivo detection, 100,000 labelled hUCBCs were injected into the spinal cord of a transgenic amyotrophic lateral sclerosis (ALS) mouse and scanned at 7.0 T. RESULTS: In vitro, 100,000 MTH53A cells and 250,000 hUCBCs were visible at 1.0 T. Scanning with 7.0 T revealed 25,000 detectable MTH53A cells. In vivo, 7.0 T MRI showed clear signals of 100,000 implanted cells. CONCLUSION: MRI combined with SPIO nanoparticles provides valuable potential for non-invasive, non-toxic in vivo tracking of cells implanted into the spinal cord.

Computer-assisted gait analysis of the dog: comparison of two surgical techniques for the ruptured cranial cruciate ligament.

OBJECTIVES: To compare the improvement in degree of lameness following surgical repair of cranial cruciate ligament rupture in dogs using computer-assisted gait analysis. METHODS: Two groups of 14 dogs were used. One group was treated by a capsular-fascial imbrication method, and the other group by tibial plateau levelling osteotomy (TPLO). All dogs underwent gait analysis prior to surgery, as well as at four days, four weeks, and four months after surgery. Symmetry indices of vertical ground reaction forces as well as vertical ground reaction forces in % body weight, joint angles and certain gait cycle parameters were evaluated. RESULTS: Four months after surgery, the degree of lameness expressed as symmetry index for peak vertical force for the TPLO group (5.83%) was not significantly different to the capsular-fascial imbrication group (19.05%). Within the TPLO group, there was a significantly increased ability to extend the stifle joint four months after surgery. The stifle motion pattern of the capsular-fascial imbrication group as well as the range-of-motion in both groups showed very little change at the time of the last gait analysis. The complication rate was greater in the TPLO group than in the capsular-fascial group. CLINICAL SIGNIFICANCE: In conclusion the results suggest that the TPLO method leads to a faster recovery and improved limb function in comparison to the capsular-fascial imbrication method four months after surgery. Further analyses are needed to determine if the TPLO method is superior concerning long-term joint stability.

[In vitro neurite outgrowth induced by BDNF and GDNF in combination with dexamethasone on cultured spiral ganglion cells]. / Neuritenwachstum in vitro durch BDNF und GDNF in Kombination mit Dexamethason auf kultivierte Spiralganglienzellen.

BACKGROUND: The efficacy of cochlear implant performance depends, among many other factors, on the number of excitable spiral ganglion cells (SGCs) and the nerve-electrode interface. In earlier animal studies it has been demonstrated that neurotrophic factors are effective to improve SGC survival after experimentally induced deafness. With regard to their anti-inflammatoric and anti-proliferative effects, glucocorticoids (e. g. dexamethasone) are potentially interesting therapeutic agents to reduce connective tissue formation around the inserted electrode. The biological effects of a combined intervention of neurotrophic factors with steroids on SGCs are unknown. Therefore the objective of the study was to investigate possible trophic or even toxic effects of brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF) and dexamethasone on neurite outgrowth of cultivated SGCs. METHODS: By using dissociated postnatal spiral ganglion cells (p3-5) for cultivation in the present study, the influence of the mentioned factors in various concentrations and combinations on neurite outgrowth of SGCs was analysed. RESULTS: Our results indicate significant trophic effects for BDNF (50 ng/ml) and a combination of BDNF with dexamethasone (100 ng/ml) on SGC neurite outgrowth. In contrast, single application of GDNF or dexamethasone in different concentrations caused no significant changes on neurite outgrowth when compared to the control condition. CONCLUSIONS: Neurite outgrowth induced by neurotrophic factors could not be observed to be reduced when dexamethasone is given at the same time. Therefore the demonstrated results provide a basis for further animal studies in this field of research.

[Neurotrophic factors of the GDNF family and their receptors are detectable in spiral ganglion cells of normal hearing as well as of deafened rats]. / Neurotrophe Faktoren der GDNF-Familie und ihre Rezeptoren lassen sich in Spiralganglienzellen hörender, aber auch ertaubter Ratten nachweisen.

BACKGROUND: Recent studies have shown that neurotrophic factors like BDNF, NT-3 and GDNF induce protective effects on spiral ganglion cells after noise- or drug-induced hearing loss. According to these studies it is suggested that deafness leads to a lack of neurotrophic factor or relating receptor expression in spiral ganglion cells, that has to be compensated by local cochlear application of these factors. METHODS: In the present study we examined the expression pattern of members of the GDNF family (GDNF, Neurturin, Artemin, Persephin) and their relating receptors (Ret, GFRalpha1 - 3) as well as BDNF and trkB on spiral ganglion cells of normal hearing and experimentally deafened rats (10 % neomycine). Indirect immunofluorescence was carried out to determine protein expression of these factors and their receptors 26 days following deafening. RESULTS: Our results demonstrate neurotrophic factor and receptor expression on spiral ganglion cells of normal hearing as well as experimentally deafened animals. CONCLUSIONS: Our data indicate that within a period of 26 days after deafening no detectable reduction of the GDNF-family member expression and their receptors was ascertainable on spiral ganglion cells by immunohistochemistry. Thus, a lack of neurotrophic factor expression is unlikely to be the only cause of spiral ganglion cell loss following deafening.