Validation of biplane high-speed fluoroscopy combined with two different noninvasive tracking methodologies for measuring in vivo distal limb kinematics of the horse.

REASON FOR PERFORMING STUDY: Biplane high-speed fluoroscopy is a new method for gait analysis of the equine distal extremity. This is the first study validating the noninvasive tracking possibilities (Autoscoping and Scientific Rotoscoping) taking equine anatomy into account. OBJECTIVES: To determine the resolution with which Autoscoping and Scientific Rotoscoping depict motion of the equine phalanges in comparison to the invasive gold standard marker-based registration. STUDY DESIGN: Comparative ex vivo study. METHODS: In 5 distal extremities of slaughtered ponies, 3 or 4 tantalum beads with 1 mm diameter were implanted in each of the proximal, middle and distal phalangeal bones. Three-dimensional models of the bones were reconstructed using computed tomographic data (120 kV, 50 mA, slice thickness 1 mm, increment 0.5). The beads were digitally removed from the bone models. Biplane fluoroscopic videos were taken at 69.5 ± 3.5 kV, 102.5 ± 22.5 mA, 500 frames/s and 0.5 ms shutter speed. The 5 specimens were moved in the trial field of the biplane fluoroscopic setup in a step-like motion (simulation of landing, main stance phase, lift-off). Marker-based registration, Autoscoping and Scientific Rotoscoping were carried out. For statistical analysis agreement was computed as percentiles, mean and s.d. RESULTS: The medians of Scientific Rotoscoping ranged from 0.16 to 0.66 mm in translations and 0.43 to 2.78° in rotations, while values for Autoscoping were 0.13-0.70 mm and 0.28-2.39° respectively. With 2 exceptions, all differences between methods were statistically significant. Scientific Rotoscoping is more time efficient than Autoscoping and results in smaller maximum errors. MAIN LIMITATIONS: The experimental set-up was specifically designed to accommodate in vivo requirements. Autoscoping was not manually corrected but rather expected to work automatically. CONCLUSIONS: It is possible to noninvasively apply both Autoscoping and Scientific Rotoscoping for gait analysis of the equine phalanges with high precision. The summary is available in Chinese - see supporting information.

Arthroscopic assisted femoral tunnel drilling for the intra-articular anatomic cranial cruciate ligament reconstruction in dogs.

OBJECTIVE: To develop and test an arthroscopic aiming device for extra- to intra-articular femoral tunnel drilling emerging at the center of the femoral insertion of the cranial cruciate ligament (CrCL) in medium to large breed dogs. MATERIAL AND METHODS: Hindlimbs (n = 12) of six cadaveric dogs (≥ 20 kg bodyweight). One hindlimb from each cadaver was randomly chosen. On a standard medio-lateral stifle radiograph the caudo-cranial position of the CrCL center was measured and transferred onto an adjustable aiming device. After arthroscopic debridement of the CrCL the aiming device was hooked behind the lateral condyle and a 2.4 mm guide pin was placed from extra- to intra-articular. The intra-articular position of the resulting bone tunnel was evaluated radiographically as well as compared to the anatomic CrCl center of the contralateral hindlimb using 3D renderings. RESULTS: According to the postoperative radiographs all six drill tunnels were located at or near the CrCL center. The median absolute 3D error from the anatomical center of the CrCL was 0.6 mm (range: 0.2-0.9 mm). CONCLUSION: Precise anatomic placement of the femoral tunnel for intra-articular repair of the CrCL was achieved using an adjustable aiming device. CLINICAL RELEVANCE: The proposed technique will reduce femoral tunnel misplacement when performing intra-articular CrCL repair in dogs. In combination with the published technique for arthroscopic tibial tunnel drilling using a similar aiming device, the technical requirements for arthroscopic assisted tunnel positioning for anatomical graft replacement are available.

Focal humero-ulnar impingement following subtotal coronoid ostectomy in six dogs with fragmented medial coronoid process.

OBJECTIVE: To report acute eburnation of joint cartilage at the humeral trochlea following subtotal coronoid ostectomy (SCO) in a clinical case series of six elbows. MATERIAL AND METHODS: Six dogs (median BW 27.1 kg; median age 7.5 months) with fragmented medial coronoid process (FCP) and varying degree of radio-ulnar incongruence (RUI) (mean 2 mm) were treated with SCO using an arthroscopic burr. Second look arthroscopy 4-12 weeks later was performed either because of recurrent or persistent lameness in three dogs. In the others, second-look arthroscopy was scheduled prospectively because of RUI, which was thought to be a risk factor for the observed humero-ulnar impingement. RESULTS: All six elbows had a 1-2 mm wide line of focal full-thickness cartilage loss along the edge of the SCO, while the opposing trochlea had diffuse cartilage damage of Outerbridge grade III-IV, indicating focal humero-ulnar impingement. None of the elbows showed repeated FCP. CONCLUSION: In some cases SCO might lead to focal humero-ulnar impingement along the osteotomy line. CLINICAL SIGNIFICANCE: Whether this relays to variations in respect the amount of resected bone (too much vs. too less) or concomitant joint pathologies like RUI or joint instability remains unknown and warrants further studies.

Radiographic location of the femoral footprint of the cranial cruciate ligament in dogs.

OBJECTIVE: To describe the radiographic location of the center of the femoral footprint of the cranial cruciate ligament (CrCL) in dogs. MATERIAL AND METHODS: Using femora from 49 adult, orthopedically sound dogs (bodyweight≥20 kg), a radiopaque marker was placed on the cranial border of the femoral footprint of the CrCL. Computed tomography and threedimensional (3D) reconstruction of each femur was performed subsequently, followed by manual segmentation of the footprint on the 3D models and calculation of its center. Finally, virtual digital radiographs in two planes were produced and the location of the calculated center of the CrCL was expressed using three different methods (4x4 box grid method and percentage position for the medio-lateral projection; o'clock position for the disto-proximal projection). RESULTS: In the medio-lateral radiographs the center of the femoral footprint was consistently located in the second rectangle from the top of the most caudal column of the 4x4 grid. The mean percentage caudo-cranial and proximo-distal location was 20.2% (±2.2) and 33.8% (±3.7), respectively. In the disto-proximal radiograph, the o'clock position of the CrCL center was between 2 and 3 o'clock in 97.6% of cases. CONCLUSION: The radiographic location of the center of the femoral footprint can be consistently predicted in medio-lateral and disto-proximal stifle radiographs of dogs over 20 kg. CLINICAL SIGNIFICANCE: The reported data can be used to plan and verify the placement of the femoral tunnel opening for intra-articular anatomic CrCL repair.

[Comparative radiologic examination of the canine elbow with and without elbow dysplasia under standardized load]. / Vergleichende röntgenologische Untersuchung von kaninen Ellbogengelenken mit und ohne Ellbogendysplasie unter standardisierten Belastungsbedingungen.

OBJECTIVE AND AIM: Application of an X-ray technique under load to determine the humeroradial and humeroulnar joint conformation of dogs with elbow dysplasia (ED). The aim of the study was to determine whether there are significant differences in the measurements of dysplastic joints compared to healthy joints. In addition, we formulated the hypothesis, that a differentiation between humeroulnar and humeroradial incongruence in dysplastic elbows can be made based on the acquired radiographic measurements. MATERIAL AND METHODS: Radiographic measurements were obtained in 149 dogs with ED and compared to the results of a control group established in a previous study. Based on frequently observed measurement variations, these 149 elbow joints were categorized into different subgroups, which we re-compared with the control group. In healthy elbow joints of euthanized dogs, four different radial and ulnar osteotomies were performed with two- and three-dimensional conformation readjustment of the elbow joint. The joints were subjected to the same radiographic measurements and the results were compared to the control and ED groups. RESULTS: There were no significant differences between the control group and all 149 ED joints. However, a marked delineation was possible because of significant differences and descriptive statistics among the four subgroups of ED joints. One of these subgroups displayed significant differences compared to all the examined groups and was labeled type I (n = 60). Because of a lack of distinction between two subgroups, these were combined and labeled type II (n = 40). Another sub-group comprising all the elbows that could not be classified as either type I or type II was labeled "indiff" (n = 49). The criteria for assigning an affected elbow joint to type I, type II or indiff were three subchondral joint space-widths, three indices calculated from the joint space-widths and one angle. CONCLUSION AND CLINICAL RELEVANCE: The technique investigated is suitable to assign a great number of affected joints to an incongruence type (type I or type II).The results of the osteotomy groups provide evidence that the three-dimensional ulnar shortening displays similarities to type I, whereas the three-dimensional radius shortening shows similarities to type II.

Sagittal joint instability in the cranial cruciate ligament insufficient canine stifle. Caudal slippage of the femur and not cranial tibial subluxation.

OBJECTIVE: This in vivo study qualitatively describes the sagittal motion pattern of the cranial cruciate ligament (CrCL) insufficient canine stifle in operated and unoperated joints with cranio-caudal laxity on palpation. MATERIAL AND METHODS: Sagittal stifle kinematics were recorded in vivo in dogs (> 15 kg BW) with unilateral (n = 7) or bilateral (n = 6) complete CrCL rupture and positive cranial drawer test as well as two sound control dogs using uniplanar fluoroscopic kinematography with the dogs walking on a treadmill. Stifle stability and sagittal motion pattern of the femur and the tibia were determined by visual inspection of the fluoroscopic video sequences. RESULTS: Control dogs showed no cranio-caudal instability, identical to the contralateral stifles of the dogs with unilateral rupture. All unoperated stifles with CrCL rupture (n = 6) showed caudal slippage of the femur at the beginning of the stance phase. Of the 13 operated stifles (TightRope: n = 1, tibial tuberosity advancement, TTA: n = 6, tibial plateau leveling osteotomy, TPLO: n = 5, cranial closing wedge osteotomy, CCWO: n = 1) nine were unstable, showing the same motion pattern as the unoperated stifles. CONCLUSION: In the CrCL insufficient stifle with in vivo cranio-caudal instability caudal slippage of the distal femur at tow touch is the predominant motion pattern. CLINICAL SIGNIFICANCE: The discrepancy between in vivo motion pattern and in vitro simulation of CrCL insufficiency in which cranial tibial subluxation is the predominant sagittal motion pattern warrants further studies.

[Radiologic quantification of the elbow conformation with a new method for acquiring standardized x-rays under load. Reference valus for medium sized and large dogs without dysplasia of the elbow joint]. / Röntgenologische Quantifizierung der Ellbogengelenkskonformation mit einer neuen standardisierten Röntgentechnik unter Last. Referenzwerte für mittelgroße und große Hunde ohne Ellbogengelenksdysplasie.

OBJECTIVE: The aim of this study was to develop a new radiographic and measurement technique for use in the canine elbow (putting axial load on the joint during radiography and obtaining objective quantification of the resulting joint conformation), assess its reliability in relation to positioning artifacts and repeat measurements as well as to establish reference values. A radiographic technique for quantifying the radioulnar congruence or incongruence under load in vivo was to be developed. MATERIAL AND METHODS: In 27 dogs free of lameness, radiographs of 47 elbow joints with or without load (medio-lateral, cranio-caudal; anaesthetised dog in lateral recumbency), as well as radiographs with the animal standing (cranio-caudal) were examined. Digital measurements of the subchondral jointspace-width, subchondral bone-width and an angle were taken. RESULTS: Reproducible length and angle measurements of anatomical landmarks in the elbow joint were obtained. By normalizing the length measurements parameters it was possible to compare radiographs taken from three different views in an animal as well as from different animals. Measurements from radiographs taken in a standing position correlated with those taken with or without load, but displayed poor reliability. The values of the measured parameters in radiographs with or without load showed a small range of dispersion, thus enabling the establishment of reference values. The examined reliabilities were significant for several parameters. CONCLUSION: Taking radiographs in the standing dog is not practical and cannot be used as a standard procedure for our measurement technique. However, using radiographs with or without load in lateral recumbency it is possible to accurately describe the canine elbow joint and compile a set of reference values in the narcotised animal. It may be possible to objectively describe unphysiologic incongruency and to adequately discriminate it from physiologic conditions.

Concentration of platelets and growth factors in canine autologous conditioned plasma.

OBJECTIVES: To report the concentration of blood cells and selected growth factors in canine autologous conditioned plasma (ACP). METHODS: The density of blood cells in whole blood (WB), ACP and standard plasma preparation (SP) of 10 healthy mature dogs was determined. In both ACP and SP, the concentration of insulin-like growth factor-1 (IGF-1), epidermal growth factor, vascular endothelial growth factor, platelet-derived growth factor-AA, platelet-derived growth factor-AB, platelet-derived growth factor-BB, transforming growth factor-ß1 (TGF-ß1), and transforming growth factor-ß2 was measured using the ELISA technique. In another ten dogs, ACP was prepared using an ultra-soft spinning protocol, and again blood cell density was compared to that obtained in WB. RESULTS: The density of platelets in ACP was significantly higher than that in SP (p = 0.0002), but there was not any significant difference between ACP and WB, nor between WB and ACP prepared using softer centrifugations. Interestingly, only for IGF-1, PDGF-BB, and TGF-ß1 could reliable measurements be obtained, showing a significant increase in PDGF-BB and TGF-ß1 concentrations in ACP compared to SP (p = 0.001, p = 0.0028). Regarding IGF-1 content, there was not any significant difference between ACP and SP. CLINICAL SIGNIFICANCE: Canine ACP prepared according to the manufacturer's recommendations, or by using a softer spin does not show the same specifications as human ACP, which shows a doubling in platelet count compared to WB. Even though canine ACP has a similar number of platelets per injected volume and consequently, probably the same amount of injected growth factors than WB, application of canine ACP would not be associated with the proinflammatory potential reported for WB, as it is almost free of erythrocytes and nucleated cells.

Cartilage thickness and split-line pattern at the canine humeral trochlea.

OBJECTIVE: To characterise the humeral trochlea in middle to large breed dogs in respect to split-line pattern and cartilage thickness. METHODS: In 15 paired cadaveric elbow joints of mature dogs (>20 kg body weight) collagen network orientation of the hyaline cartilage of the humeral trochlea was visualised using a traditional split-line technique in which a dissecting needle dipped in India ink was inserted into the cartilage (n = 10). Cartilage thickness was measured radiographically on osteochondral plugs harvested at four representative locations within the joint surface of the humeral trochlea (n = 15). RESULTS: The joint surface of the humeral trochlea showed a distinct pattern of centripetally oriented split-lines with less pronounced or even absent split-lines caudo- proximally towards the olecranon fossa. Median cartilage thickness at the canine humeral trochlea was 0.51 mm (interquartile range: 0.42 - 0.61 mm). Centrally, at the region where osteochondrosis lesions commonly occur in middle to large breed dogs, the median cartilage thickness was 0.55 mm (interquartile range: 0.48 - 0.62 mm). CLINICAL SIGNIFICANCE: When focusing on anatomical joint resurfacing while performing osteochondral transplantation at the canine humeral trochlea, transplants should be implanted such that their split-lines are oriented centripetally. Hyaline cartilage thickness of transferred grafts should be in the range of half a millimetre to optimally match the situation at the canine humeral trochlea.

[Stifle stability after lateral suture stabilisation using Ethibond Excel®: early destabilisation following cyclic passive joint motion]. / Kniegelenkstabilität nach lateraler Fadenzügelung mit Ethibond Excel®: frühzeitige Destabilisierung nach passiver Gelenkbewegung.

OBJECTIVE: 1) To report cranio-caudal stifle stability (ccStab) following lateral suture stabilisation (LSS) and passive joint motion. 2) To report tension within the suture following knotting. MATERIAL AND METHODS: ccStab was measured in vitro on latero-medial radiographs in 10 stifles of orthopaedically sound dogs (> 20 kg BW). ccStab was assessed in the intact joint, after transection of the cranial cruciate ligament and following LSS using a multi strand Ethibond loop and clamped square knots, as well as after 50, 100, 250 and 350 cycles of passive joint motion. Tension within seven suture loops was measured using a material testing machine. Tension was measured after the first (FMax) and last knot (FEnd). RESULTS: ccStab following LSS was 3.7 mm und was greater by 2.7 mm than with intact cruciate ligament. Already 250 passive cycles of passive joint motion induced significant destabilisation by 1.5 mm. FMax was 133 N und dropped to 6 N (FEnd) after completion of the last knot. CONCLUSION: LSS using Ethibond and clamped square knots do not allow for restoration of physiological stifle stability. Already few cycles of passive joint motion further destabilise the joint. One of the reasons for these disappointing results is the method of suture fixation as clamped square knots did not allow for conservation of initial loop tension. CLINICAL RELEVANCE: LSS using a multi strand Ethibond loop and clamped square knots should be avoided.

[Radiographic location of the tibial cranial cruciate ligament attachment in middle- to large breed dogs]. / Röntgenologische Lage des vorderen Kreuzbandansatzes bei mittel- und großwüchsigen Hunden.

OBJECTIVE: Investigation of the radiographic cranio-caudal (cc) and medio-lateral (ml) location of the tibial centroid of the attachment area of the CCL (ACCL). MATERIAL AND METHODS: In 46 tibiae from orthopedically healthy dogs (22-50kg) the tibial plateau was stripped of all soft tissue, degreased with acetone and the contour of the ACCL was marked with ink stain. The CCL was completely resected and one pin each was placed at the most medial, lateral, cranial and caudal extensions of the ACCL. On digital images of each tibial plateau the previously marked contour of the ACCL was traced. Using custom-made image analysis software the two-dimensional centroid of the ACCL was determined and transferred to standard radiographs in two planes of each tibia. The cc location of the centroid of the ACCL was measured starting at the intercondylar tubercles. The proximal tibial extension (TibEx) was obtained and linear regression analysis was applied to develop a mathematical first order equation for the calculation of the cc location of the centroid based on the proximal tibial depth in the individual stifle. The ml location of the centroid was measured in relation to the medial intercondylar tubercle. RESULTS: A statistically significant (p<0.001) correlation was found between the TibEx and the anatomical cc location of the centroid. Linear regression analysis revealed a first order linear equation for calculation of the individual cc location of the centroid in mm to be: 0.28 x TibEx - 4 in mm with an R2 of 0.83. The median ml location of the centroid in relation to the medial intercondylar tubercle was 0mm whereas 90% were located 1 mm medial and 1 mm lateral to the medial intercondylar tubercle. CONCLUSION: The radiographic location of the centroid of the ACCL can be individually determined on standard stifle radiographs. CLINICAL RELEVANCE: With the help of these data the location of a tibial drill tunnel in anatomic reconstruction of the ruptured CCL may be evaluated either intra-operatively with fluoroscopy or postoperatively on two plane standard stifle radiographs and the placement could be corrected when necessary.

Sensitivity and specificity of arthroscopic estimation of positive and negative radio-ulnar incongruence in dogs. An in vitro study.

OBJECTIVES: To determine the sensitivity and specificity of arthroscopic estimation of positive and negative radio-ulnar incongruence (RUI) in the canine elbow joint. METHODS: Experimental radial shortening and lengthening by 1 and 2 mm increments were performed in nine right elbow joints, extending an established surgical in vitro model of RUI. Arthroscopic estimation of each artificially produced radio-ulnar joint conformation (RUJC) was done using a graduated hook probe. A total of 72 RUJC were blindly evaluated in a random manner by an independent investigator and estimated in 1 mm increments (-2, -1, 0, +1, +2). RESULTS: The sensitivity for identification of an incongruent joint was 0.98 (95% CI: 0.90 to 0.99). The specificity for identification of a congruent joint was 0.89 (95% CI: 0.65 to 0.98). Analysing the data only in respect to a congruent joint versus one with a shortened radius (positive RUI) resulted in a sensitivity of 0.96 (95% CI: 0.80 to 0.99) and a specificity of 1.00 (95% CI: 0.92 to 1.00). CLINICAL SIGNIFICANCE: Accurate estimation of RUI in dogs affected by elbow dysplasia might improve functional outcome and prevent osteoarthritis when corrective or modifying osteotomies are being considered as part of the treatment plan. Arthroscopy has been shown to be highly accurate and precise in detecting both positive and negative RUI in vitro. However, its diagnostic strength under clinical conditions still has to be proven.

[Cost analysis of a universal newborn hearing screening for clinics using the State of Hesse as an example]. / Kostenanalyse des universellen Neugeborenen-Hörscreenings für Kliniken am Beispiel Hessens.

BACKGROUND: The implementation of a universal newborn hearing screening (UNHS) in Germany in 2009 requires a realistic cost calculation for health insurance companies and participating clinics MATERIAL AND METHODS: Screening costs from 60 Hessian clinics were analyzed over 2.5 years whereby 94,203 children had been screened either with a 2-step (TEOAE, AABR) or a 1-step procedure (AABR). RESULTS: The TEOAE-AABR screening at EUR 13.16 per child was more cost-efficient. For a population with a high rate of at-risk babies a sole AABR device with screening costs of EUR 16.87 presents a more efficient alternative. High quality of screening performance and qualification of screening staff markedly reduced total cost. Overhead costs for tracking, quality assurance, control of completeness, and securing structural screening requirements, considered as essential screening costs, were calculated at EUR 4.00 per child. The total costs in Hesse would therefore be EUR 17.16 per child for TEOAE-AABR screening and EUR 20.87 per child for an AABR screening. CONCLUSION: In a mixed calculation which can be cautiously extrapolated from the Hessian data for Germany as a whole, costs would be EUR 18.40 per registered child.

[Quality assurance of a universal newborn hearing screening. Recommendations of the German Society of Phoniatrics and Pediatric Audiology]. / Qualitätssicherung eines universellen Neugeborenen-Hörscreenings. Empfehlungen der Deutschen Gesellschaft für Phoniatrie und Pädaudiologie.

Statutory implementation of a universal newborn hearing screening requires a continuous quality assurance monitoring. Therefore, at the Annual Meeting in 2007, the members of the German Society of Phoniatrics and Pediatric Audiology passed a recommendation on measures of quality assurance applied to newborn hearing screening. This recommendation describes the procedures, performance, location, time frame, and technical prerequisites of the screening and of potentially necessary follow-ups, the definition of hearing loss to be detected, the performing and responsible professional groups and their qualifications for the screening, the regulation of repeat and control screenings, the confirmation diagnostics and initiation of therapy, the information of parents, the documentation of screening results, the aims and organization of a tracking system, the tasks of regional screening centers and of a supraregional institution for the quality assurance of the hearing screening, the central collection of person and screening-related quality relevant data, and the accessibility of defined data sets as predisposition for cost analyses and quality reports.

[Universal newborn hearing screening. Methodical aspects]. / Universelles Neugeborenen-Hörscreening. Aspekte des methodischen Vorgehens.

BACKGROUND: In order to prepare for the introduction of a universal newborn hearing screening program on a larger scale, TEOAE and ABR were recorded on automated screening instruments from both ears of 501 newborns at the University Hospital Heidelberg over a period of 13 months. The parents of children in whom OAE and ABR could not be detected in both ears, were requested to allow a complete exploration of the auditory status of the children at the department of pediatric audiology. SUBJECTS AND METHODS: Internally available data networks were used for the acquisition and evaluation of data and for the organization of tracking and follow-up. Of the children 35% exhibited risk factors for congenital hearing impairment. RESULTS: The pass rate was 98.7% for the exclusion of binaural and 91.6% for monaural hearing disorders (TEOAE or ABR detectable). On the basis of the data it can be shown how pass rates can be optimized by selecting a suitable moment for the examination and by prescribing a minimum number of test repetitions (3 for TEOAE and 2 for AABR). CONCLUSION: Quality control of screening programs should include these parameters and, in particular the number of repetitions of test measurements in all screening steps.

Magnetic resonance imaging diagnosis: incomplete ossification of the humeral condyle in a German shepherd dog.

Clinical signs, radiological, arthroscopic findings and magnetic resonance imaging features of a male German shepherd dog with incomplete ossification of the humeral condyle are described. The dog showed recurrent left forelimb lameness and pain on elbow palpation. In routine radiographs, the lesion was obscured. In oblique radiographs, a radiolucent line was detected, and magnetic resonance imaging clearly demonstrated a defect in the humeral condyle. However, arthroscopy showed no changes or discontinuity of the humeral cartilage. Incomplete ossification of the humeral condyle may be underrepresented in conventional, routine studies because if there is concurrent additional elbow pathology (for example fragmented coronoid process), treatment may lead to clinical improvement and further diagnostic techniques may not be performed. The benefit of magnetic resonance imaging in this case is demonstrated.

Computer-assisted magnetic resonance imaging brain morphometry in American Staffordshire Terriers with cerebellar cortical degeneration.

BACKGROUND: Cerebellar cortical degeneration exists in American Staffordshire Terriers. Magnetic resonance imaging (MRI) can be suggestive, but a definitive diagnosis requires histopathology. HYPOTHESIS: Computer-assisted MRI morphometry can be used to distinguish between American Staffordshire Terriers with or without cerebellar cortical degeneration. ANIMALS: Normal American Staffordshire Terriers (n = 17) and those with clinical signs of cerebellar cortical degeneration (n = 14). METHODS: This was a partly retrospective and partly prospective study. Causes of cerebellar disease were ruled out with brain MRI, cerebrospinal fluid (CSF) analysis, CBC, blood biochemistry, and clinical follow-up. On T2-weighted midsagittal MR images, the following parameters were calculated: size of the cerebellum relative to the entire brain, size of the CSF space surrounding the cerebellum relative to the cerebellum, and 2 threshold-dependent cerebellar CSF indices (with and without surrounding CSF). RESULTS: Statistical analyses indicated a significantly lower relative cerebellar size (P < .001) and a larger relative cerebellar CSF space (P < .001) in dogs with cerebellar cortical degeneration. The measurement of relative cerebellar size could distinguish between affected and nonaffected dogs with a sensitivity and a specificity of 93 and 94%, respectively, using a cut-off of 13.3%. Using a cut-off of 12.8%, the measurement of relative CSF space could distinguish between both groups with a sensitivity of 93% and a specificity of 100%. There was a significant difference in 1 of the 2 CSF indices between affected and normal dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: Relative cerebellar size and relative CSF space calculated from MRI are effective in American Staffordshire Terriers to differentiate between normal animals and those with cerebellar cortical degeneration.

Liposuction--removal of giant lipomas for weight loss in a dog with severe hip osteoarthritis.

An extremely obese, mixed breed dog, with severe bilateral hip osteoarthritis was presented with progressive hindlimb lameness. In addition, three giant lipomas were diagnosed, one causing mechanical irritation within the left axillary region. Previous treatments of dietary weight loss and non-steroidal anti-inflammatory drugs had failed. Minimally invasive liposuction of the lipomas was performed, resulting in weight loss of 3 kg, representing 10 per cent of the dog's bodyweight. Conservative treatment was continued, and the dog improved rapidly postoperatively. Liposuction of lipomas may be considered as an alternative to traditional surgical resection in cases where seroma formation and delayed wound healing may be expected. Acute weight loss through liposuction may improve lameness associated with osteoarthritis and motivate the owner compliance for further weight loss.

Halogenodisilanes: precursors for new disilane derivatives.

Starting from hexachloro- or hexabromodisilane a wide variety of 1,2-disubstituted tetrachlorodisilanes (RSiCl2SiCl2R) [R = Cp (2a), 4-iPrC6H4(SiMe3)N (2b), 2,6-iPr2C6H3(SiMe3)N (2c), (Me3Si)2CH (2d) (Me3Si)3C (2e), (Me3Si)3Si (2f)], tetrabromodisilanes (RSiBr2SiBr2R) [R = Cp (3a), 4-iPrC6H4(SiMe3)N (3b), (Me3Si)3Si (3f)] and the monosubstituted pentahalogenodisilanes CpSiX2SiX3 [X = Cl (4), Br (5)] were prepared. The tetrachlorodisilanes 2a-e are converted to various functionalized disilanes. Ammonolysis of 2a-e leads to the tetraaminodisilanes [RSi(NH2)2Si(NH2)2R] 6a-e. A reduction of 2d with LiAlH4 resulted in the formation of the disilane RSiH2SiH2R [R = (Me3Si)2CH] 7 and the metathesis with Me3SnF yielded the tetrafluorodisilane RSiF2SiF2R [R = (Me3Si)2CH] 8. Treatment of 6d with reagents containing H acidic protons (HX) [X = Br, I and OH] leads under elimination of NH3 to the tetrabromo- R2SiBr2SiBr2R (3d) tetraiodo- RSiI2SiI2R (9) and the tetrahydroxodisilane RSi(OH)2Si(OH)2R (10) [R = (Me3Si)2CH]. Single-crystal X-ray structural analysis of 2d, 6a, 6d, and 9 are reported.