Gait analysis in French bulldogs with and without vertebral kyphosis.

The study objective was to compare temporal-spatial and kinetic gait variables in neurologically normal French bulldogs with and without vertebral kyphosis. French bulldogs presented to a dedicated brachycephalic clinic were prospectively enrolled. All dogs underwent general physical, orthopaedic, and neurological examination prior to study inclusion. The presence of vertebral kyphosis was evaluated by computed tomography and kyphosis was defined as a Cobb angle exceeding 10°. Gait variables were collected using a pressure-sensitive GAITRite walkway with GAITFour software and included measurement of total pressure index (TPI) defined as the sum of peak pressure values recorded from each activated sensor by a paw during mat contact. Fifteen French bulldogs with (n=8) and without kyphosis (n=7) were included. Cobb angle in kyphotic dogs ranged from 14.9° to 39.5°. Univariate analyses were initially performed to examine the association between kyphosis and 16 gait variables. When those variables found to be associated (P<0.2) were taken forward into multivariate generalised linear mixed models (accounting for dog, velocity and side), kyphosis had a significant effect upon TPI of the forelimbs and TPI symmetry ratio (P<0.05); however, the size of these effects was small. Although vertebral kyphosis is rarely associated with neurological deficits, it was associated with subtle alterations in kinetic gait variables (TPI forelimbs and TPI symmetry ratio). Further studies are needed to evaluate the clinical importance of altered gait variables in French bulldogs with kyphosis.

Surgical management of chronic otitis secondary to craniomandibular osteopathy in three West Highland white terriers.

Three West Highland white terriers were presented for investigation of left-sided para-aural abscessation. CT revealed chronic otitis media with extensive osseous proliferation surrounding the horizontal and vertical ear canals contiguous with the expanded temporal bone, consistent with a unilateral variant of craniomandibular osteopathy. A left total ear canal ablation with lateral bulla osteotomy was performed in all dogs. An ultrasonic bone curette (Sonopet; Stryker) proved useful when removing the osseous proliferation in two dogs. Histopathological examination of the ear canals was consistent with craniomandibular osteopathy and the treatment led to resolution of the presenting clinical signs in all dogs. To our knowledge, this is the first report of craniomandibular osteopathy engulfing the external ear canal, presumably leading to chronic otitis media and para-aural abscess formation. This is also the first reported use of an ultrasonic bone curette in canine otic surgery.

Relationship between brachycephalic airway syndrome and gastrointestinal signs in three breeds of dog.

OBJECTIVES: To assess the breed-specific prevalence of, and effects of corrective airway surgery on, gastrointestinal signs in French bulldogs, English bulldogs and pugs presenting with brachycephalic airway syndrome to a referral teaching hospital. MATERIALS AND METHODS: In this retrospective study, ptyalism, regurgitation and vomiting were graded at presentation using a previously established scoring system. Staphylectomy and nares resection were performed on all dogs. Gastrointestinal signs were re-assessed via telephone follow-up at least 6 weeks after surgery. RESULTS: Ninety-eight dogs were included: French bulldogs (n=43), English bulldogs (n=12) and pugs (n=43). Overall population prevalence of all gastrointestinal signs was 56%. Breed-specific prevalence for French bulldogs was 93%, English bulldogs 58% and pugs 16%. There was post-surgical clinical improvement in gastrointestinal signs for the whole study population, especially in French bulldogs. CLINICAL SIGNIFICANCE: The prevalence of gastrointestinal signs in dogs presenting with brachycephalic airway syndrome and improvement in these clinical signs following corrective surgery may vary between breeds.

Evaluation of Quality of Life Outcomes Following Palliative Treatment of Bone Metastases with Magnetic Resonance-guided High Intensity Focused Ultrasound: An International Multicentre Study.

AIMS: To determine quality of life (QoL) outcomes after palliation of pain from bone metastases using magnetic resonance-guided high intensity focused ultrasound (MR-guided HIFU), measured using the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C15-PAL and the QLQ-BM22 questionnaires. MATERIALS AND METHODS: Twenty patients undergoing MR-guided HIFU in an international multicentre trial self-completed the QLQ-C15-PAL and QLQ-BM22 questionnaires before and on days 7, 14, 30, 60 and 90 post-treatment. Descriptive statistics were used to represent changes in symptom and functional scales over time and to determine their clinical significance. QoL changes were compared in pain responders and non-responders (who were classified according to change in worst pain score and analgesic intake, between baseline and day 30). RESULTS: Eighteen patients had analysable QoL data. Clinically significant improvements were seen in the QoL scales of physical functioning, fatigue, appetite loss, nausea and vomiting, constipation and pain in the 53% of patients who were classified as responders at day 30. No significant changes were seen in the 47% of patients who were non-responders at this time point. CONCLUSION: Local treatment of pain from bone metastases with MR-guided HIFU, even in the presence of disseminated malignancy, has a substantial positive effect on physical functioning, and improves other symptomatic QoL measures. This indicated a greater response to treatment over and above pain control alone. MR-guided HIFU is non-invasive and should be considered for patients with localised metastatic bone pain and poor QoL.

Combining radiation with hyperthermia: a multiscale model informed by in vitro experiments.

Combined radiotherapy and hyperthermia offer great potential for the successful treatment of radio-resistant tumours through thermo-radiosensitization. Tumour response heterogeneity, due to intrinsic, or micro-environmentally induced factors, may greatly influence treatment outcome, but is difficult to account for using traditional treatment planning approaches. Systems oncology simulation, using mathematical models designed to predict tumour growth and treatment response, provides a powerful tool for analysis and optimization of combined treatments. We present a framework that simulates such combination treatments on a cellular level. This multiscale hybrid cellular automaton simulates large cell populations (up to 107 cells) in vitro, while allowing individual cell-cycle progression, and treatment response by modelling radiation-induced mitotic cell death, and immediate cell kill in response to heating. Based on a calibration using a number of experimental growth, cell cycle and survival datasets for HCT116 cells, model predictions agreed well (R2 > 0.95) with experimental data within the range of (thermal and radiation) doses tested (0-40 CEM43, 0-5 Gy). The proposed framework offers flexibility for modelling multimodality treatment combinations in different scenarios. It may therefore provide an important step towards the modelling of personalized therapies using a virtual patient tumour.

Complications following laryngeal sacculectomy in brachycephalic dogs.

OBJECTIVES: To evaluate the effect of sacculectomy on the immediate postoperative complication rate in dogs affected with brachycephalic obstructive airway syndrome. MATERIALS AND METHODS: Retrospective review of clinical records of brachycephalic dogs with everted saccules that underwent surgery for brachycephalic obstructive airway syndrome between 2009 and 2014. Dogs were grouped as those having nares resection and staphylectomy only and those having nares resection, staphylectomy and laryngeal sacculectomy. Complications were scored as mild, moderate or severe. RESULTS: In total, 37 dogs were included in the sacculectomy group and 44 in the comparator group. Dogs that had undergone sacculectomy were more likely to develop postoperative complications, with 18 of 37 developing complications, nine of which were moderate to severe. In the group without sacculectomy, nine of 44 dogs developed complications, of which one was severe. Different breed distribution between groups might also impact this outcome. CLINICAL SIGNIFICANCE: The results suggest that sacculectomy might increase morbidity following brachycephalic airway surgery, but repeat studies are required to confirm this result. Further information is also required to determine whether the short-term risks of sacculectomy are outweighed by superior long-term functional outcome.

Prevalence of thoracic vertebral malformations in French bulldogs, Pugs and English bulldogs with and without associated neurological deficits.

Congenital vertebral malformations are common incidental findings in small breed dogs. This retrospective observational study evaluated the type and prevalence of thoracic vertebral malformations in 171 neurologically normal and 10 neurologically abnormal screw-tailed brachycephalic dogs. Neurologically normal dogs underwent CT for reasons unrelated to spinal disease, while affected dogs underwent MRI. Imaging studies were reviewed and vertebral malformations including hemivertebrae, block vertebrae, transitional vertebrae, and spina bifida were documented. The group of clinically normal dogs consisted of 62 French bulldogs, 68 Pugs and 41 English bulldogs. The group of affected dogs consisted of one French bulldog and nine Pugs. Overall, 80.7% of neurologically normal animals were affected by at least one vertebral malformation. There was a significant influence of breed, with thoracic vertebral malformations occurring more often in neurologically normal French bulldogs (P <0.0001) and English bulldogs (P = 0.002). Compared to other breeds, hemivertebrae occurred more often in neurologically normal French bulldogs (93.5%; P < 0.0001 vs. Pugs; P = 0.004 vs. English bulldogs) and less often in neurologically normal Pugs (17.6%; P = 0.004 vs. English bulldogs). Neurologically normal Pugs were more often diagnosed with transitional vertebrae and spina bifida compared to other breeds (P <0.0001 for both malformations). Of Pugs included in the study, 4.7% were diagnosed with clinically relevant thoracic vertebral malformations. When compared to the general veterinary hospital population, this was significantly more than the other two breeds (P = 0.006). This study indicates that thoracic vertebral malformations occur commonly in neurologically normal screw-tailed brachycephalic dogs. While hemivertebrae are often interpreted as incidental diagnostic findings, they appear to be of greater clinical importance in Pugs compared to other screw-tailed brachycephalic breeds.

Nasal infestation by Linguatula serrata in a dog in the UK: a case report.

A two-year-old, female neutered, cross-breed dog imported from Romania was diagnosed with nasal infestation of Linguatula serrata after she sneezed out an adult female. The dog was presented with mucopurulent/sanguinous nasal discharge, marked left-sided exophthalmia, conjunctival hyperaemia and chemosis. Computed tomography and left frontal sinusotomy revealed no further evidence of adult parasites. In addition, there was no evidence of egg shedding in the nasal secretions or faeces. Clinical signs resolved within 48 hours of sinusotomy, and with systemic broad-spectrum antibiotics and non-steroidal anti-inflammatory drugs. Recommendations are given in this report regarding the management and follow-up of this important zoonotic disease.

Equivalence of cell survival data for radiation dose and thermal dose in ablative treatments: analysis applied to essential tremor thalamotomy by focused ultrasound and gamma knife.

Thermal dose and absorbed radiation dose have historically been difficult to compare because different biological mechanisms are at work. Thermal dose denatures proteins and the radiation dose causes DNA damage in order to achieve ablation. The purpose of this paper is to use the proportion of cell survival as a potential common unit by which to measure the biological effect of each procedure. Survival curves for both thermal and radiation doses have been extracted from previously published data for three different cell types. Fits of these curves were used to convert both thermal and radiation dose into the same quantified biological effect: fraction of surviving cells. They have also been used to generate and compare survival profiles from the only indication for which clinical data are available for both focused ultrasound (FUS) thermal ablation and radiation ablation: essential tremor thalamotomy. All cell types could be fitted with coefficients of determination greater than 0.992. As an illustration, survival profiles of clinical thalamotomies performed by radiosurgery and FUS are plotted on a same graph for the same metric: fraction of surviving cells. FUS and Gamma Knife have the potential to be used in combination to deliver a more effective treatment (for example, FUS may be used to debulk the main tumour mass, and radiation to treat the surrounding tumour bed). In this case, a model which compares thermal and radiation treatments is valuable in order to adjust the dose between the two.

Video-otoscopy-guided tympanostomy tube placement for treatment of middle ear effusion.

OBJECTIVE: To describe video-otoscopy-guided tympanostomy tube placement in 12 cavalier King Charles spaniels with middle ear effusion and assess the clinical outcome. METHODS: A retrospective review of medical records of cavalier King Charles spaniels diagnosed with middle ear effusion and treated with tympanostomy tubes placement between 2012 and 2014 was performed. Outcome was assessed based on a telephone questionnaire. RESULTS: Twenty-two tympanostomy tubes were successfully placed in the tympanic membrane in 12 cavalier King Charles spaniels under video-otoscopic guidance using a rigid endoscope and grasping forceps. Follow-up based on an owner questionnaire was available for 11/12 dogs. Subjective improvement in hearing was observed in 9/11 dogs with three dogs achieving normal hearing, according to the owners, and six demonstrating partial improvements. Out of 11 dogs, 10 dogs were reported with improved quality of life. Pruritus of the ears resolved in 3/9 dogs. Clinical signs recurred in four dogs because of tube dislodgement. CLINICAL SIGNIFICANCE: Video-otoscopic tympanostomy tube placement appeared to be indicated as a treatment for middle ear effusion in cavalier King Charles spaniels. It subjectively improved hearing, pruritus and quality of life in most dogs. The tympanostomy tubes dislodged in some cases, leading to recurrence of clinical signs, which were effectively eliminated by replacement of a fresh tube.

The use of high-intensity focused ultrasound as a novel treatment for painful conditions-a description and narrative review of the literature.

High-intensity focused ultrasound (HIFU) is a non-invasive technique that allows a small, well-circumscribed thermal lesion to be generated within a tissue target. Tissue destruction occurs due to direct heating within the lesion and the mechanical effects of acoustic cavitation. HIFU has been used in a broad range of clinical applications, including the treatment of malignancies, uterine fibroids and cardiac arrhythmias. Interest in the use of the technique to treat pain has recently increased. A number of painful conditions have been successfully treated, including musculoskeletal degeneration, bone metastases and neuropathic pain. The exact mechanism by which HIFU results in analgesia remains poorly understood, but it is thought to be due to localised denervation of tissue targets and/or neuromodulatory effects. The majority of studies conducted investigating the use of HIFU in pain are still at an early stage, although initial results are encouraging. Further research is indicated to improve our understanding of the mechanisms underlying this treatment and to fully establish its efficacy; however, it is likely that HIFU will play a role in pain management in the future. This narrative review provides a synthesis of the recent, salient clinical and basic science research related to this topic and gives a general introduction to the mechanisms by which HIFU exerts its effects.

An assessment of the DORT method on simple scatterers using boundary element modelling.

The ability to focus through ribs overcomes an important limitation of a high-intensity focused ultrasound (HIFU) system for the treatment of liver tumours. Whilst it is important to generate high enough acoustic pressures at the treatment location for tissue lesioning, it is also paramount to ensure that the resulting ultrasonic dose on the ribs remains below a specified threshold, since ribs both strongly absorb and reflect ultrasound. The DORT (décomposition de l'opérateur de retournement temporel) method has the ability to focus on and through scatterers immersed in an acoustic medium selectively without requiring prior knowledge of their location or geometry. The method requires a multi-element transducer and is implemented via a singular value decomposition of the measured matrix of inter-element transfer functions. The efficacy of a method of focusing through scatterers is often assessed by comparing the specific absorption rate (SAR) at the surface of the scatterer, and at the focal region. The SAR can be obtained from a knowledge of the acoustic pressure magnitude and the acoustic properties of the medium and scatterer. It is well known that measuring acoustic pressures with a calibrated hydrophone at or near a hard surface presents experimental challenges, potentially resulting in increased measurement uncertainties. Hence, the DORT method is usually assessed experimentally by measuring the SAR at locations on the surface of the scatterer after the latter has been removed from the acoustic medium. This is also likely to generate uncertainties in the acoustic pressure measurement. There is therefore a strong case for assessing the efficacy of the DORT method through a validated theoretical model. The boundary element method (BEM) applied to exterior acoustic scattering problems is well-suited for such an assessment. In this study, BEM was used to implement the DORT method theoretically on locally reacting spherical scatterers, and to assess its focusing capability relative to the spherical focusing case, binarised apodisation based on geometric ray tracing and the phase conjugation method.

A comparison of methods for focusing the field of a HIFU array transducer through human ribs.

A forward model, which predicts the scattering by human ribs of a multi-element high-intensity focused ultrasound transducer, was used to investigate the efficacy of a range of focusing approaches described in the literature. This forward model is based on the boundary element method and was described by Gélat et al (2011 Phys. Med. Biol. 56 5553-81; 2012 Phys. Med. Biol. 57 8471-97). The model has since been improved and features a complex surface impedance condition at the surface of the ribs. The inverse problem of focusing through the ribs was implemented on six transducer array-rib topologies and five methods of focusing were investigated, including spherical focusing, binarized apodization based on geometric ray tracing, phase conjugation and the decomposition of the time-reversal operator method. The excitation frequency was 1 MHz and the array was of spherical-section type. Both human and idealized rib topologies were considered. The merit of each method of focusing was examined. It was concluded that the constrained optimization approach offers greater potential than the other focusing methods in terms of maximizing the ratio of acoustic pressure magnitudes at the focus to those on the surface of the ribs whilst taking full advantage of the dynamic range of the phased array.

Pathophysiological mechanisms of high-intensity focused ultrasound-mediated vascular occlusion and relevance to non-invasive fetal surgery.

High-intensity focused ultrasound (HIFU) is a non-invasive technology, which can be used occlude blood vessels in the body. Both the theory underlying and practical process of blood vessel occlusion are still under development and relatively sparse in vivo experimental and therapeutic data exist. HIFU would however provide an alternative to surgery, particularly in circumstances where serious complications inherent to surgery outweigh the potential benefits. Accordingly, the HIFU technique would be of particular utility for fetal and placental interventions, where open or endoscopic surgery is fraught with difficulty and likelihood of complications including premature delivery. This assumes that HIFU could be shown to safely and effectively occlude blood vessels in utero. To understand these mechanisms more fully, we present a review of relevant cross-specialty literature on the topic of vascular HIFU and suggest an integrative mechanism taking into account clinical, physical and engineering considerations through which HIFU may produce vascular occlusion. This model may aid in the design of HIFU protocols to further develop this area, and might be adapted to provide a non-invasive therapy for conditions in fetal medicine where vascular occlusion is beneficial.