Bone-anchored hearing aids and chronic pain: a long-term complication and a cause for elective implant removal.

OBJECTIVES: To report a case series of elective removal of bone-anchored hearing aid implants, and reasons for removal. DESIGN: Retrospective review of a prospectively collected database. SETTING: Two tertiary referral centres in the Manchester area: Manchester Royal Infirmary and Salford Royal University Hospital. PARTICIPANTS: A series of 499 adults and children who had undergone a total of 602 implant insertions (1984-2008). MAIN OUTCOME MEASURES: Implant removal rates, and reasons. RESULTS: Twenty-seven of the 602 implants (4.5 per cent) required removal. Of these, 12 were due to pain (2.0 per cent), seven to persistent infection (1.2 per cent), three to failure of osseointegration (0.5 per cent), three to trauma (0.5 per cent) and two to other reasons (0.4 per cent). CONCLUSION: Chronic implant site pain represents the main reason why implants are removed electively, and affects 2 per cent of all implants. This complication has important medico-legal implications and should be discussed when obtaining informed consent for implantation.

A virtual-reality subtotal tonsillectomy simulator.

OBJECTIVES: To develop a virtual-reality subtotal tonsillectomy simulation for surgical training. MATERIALS AND METHODS: Computer models of a male patient's head and throat, and the surgical instrument, were created. These models were combined with custom-built simulation software. Recently developed tissue simulation technology that exploits recent developments in programmable graphics processing units was used to model tonsillar tissue in a way that allows surgical interaction whilst providing accurate tactile feedback. Current real-time rendering techniques were used to provide realistic visuals. Iterative refinements were made to the simulation, and in particular the tissue simulation, in consultation with relevantly experienced surgeons. RESULTS: We have used newly developed tissue simulation technology to developed a novel virtual-reality subtotal tonsillectomy simulation for surgical training, the first of its kind. CONCLUSION: Early feedback suggests that this simulator can help surgeons to rapidly acquire subtotal tonsillectomy surgical skills in a risk-free and realistic virtual environment.

Complications of bone-anchored hearing aid implantation.

INTRODUCTION: Bone-anchored hearing aid implantations have been performed in Manchester for over 20 years. This study examined a range of variables that can occur during the implantation process, and the effect they may have on successful outcome. METHOD: Retrospective study and literature review. LOCATION: Tertiary referral centre in central Manchester. RESULTS: Details of 602 bone-anchored hearing aid implantation procedures were retrieved from the departmental database. The overall complication rate was 23.9 per cent. The rate of revision surgery was 12.1 per cent. CONCLUSION: This study involved a significantly larger number of patients than any previously reported, similar study. Possible reasons for differences in outcomes, and recommendations for best practice, are discussed.

Outcomes for patients referred urgently with suspected head and neck cancer.

INTRODUCTION: The 1998 National Health Service White Paper stated that anyone suspected of having a cancer would be seen by a specialist within two weeks. The 'trigger symptoms' prompting such referral have been nationally agreed by the National Institute for Health and Clinical Excellence. This study aimed to quantify the diagnostic yield of urgent referrals for suspected head and neck malignancy, and to identify reasons why patients ultimately diagnosed with malignancy may not have been referred via this pathway. MATERIALS AND METHODS: All patients referred to the trust with suspected head and neck malignancy in 2005 were included in the study. Data were obtained on date of referral, date of appointment, reason for referral and which National Institute for Health and Clinical Excellence guideline heading the referral fell under, clinical findings, and final diagnosis. Concurrently, all patients in the trust with a histological diagnosis of head and neck malignancy were identified using the computer records of the pathology department. RESULTS: One hundred and seventy-seven patients were referred with suspected head and neck malignancy over the one-year study period. Of these, 169 were seen within two weeks. The commonest causes of referral were hoarseness and neck lumps. Of these patients, 22 (12 per cent) were ultimately diagnosed with malignancy. During the one-year study period, 39 patients were diagnosed hospital-wide with head and neck malignancy, 17 of whom had not been referred via the urgent referral pathway. No unifying theme was identified to explain why these patients had not been referred via this pathway. CONCLUSION: In a group of patients with symptoms suggestive of head and neck malignancy, only 12 per cent were ultimately diagnosed with cancer. Of all the patients within the trust diagnosed with head and neck cancer, 44 per cent had come from outside the urgent referral pathway.

Horner's syndrome following tonsillectomy.

Tonsillectomy is one of the commonest procedures performed in the United Kingdom. Peri-operative infiltration of local anaesthetic is a well documented adjunct to post-operative analgesia. We report the first case of temporary Horner's syndrome in a patient who received such treatment and postulate an anatomical explanation.

Risk factors associated with Neospora caninum abortion in Ontario Holstein dairy herds.

The objective of this epidemiological study was to identify risk factors for Neospora caninum-related abortions in Ontario Holstein dairy herds. A total of 88 herds, consisting of 5080 cattle, and utilizing Dairy Herd Improvement (DHI) services, were divided into three groups. Case (n = 30) and first control (n = 31) herds were selected from 1998 and 1999 fetal abortion submissions to the Animal Health Laboratory, University of Guelph, that were histopathologically positive or negative, respectively, for N. caninum. A second control group (n = 27) was selected from multiple sources of herds sampled within the previous 4 years that had a low seroprevalence (<7%) to N. caninum. Between May and December 1999, all available cows on all farms, in parity one or greater, were blood sampled. The sera were then analyzed for antibody to N. caninum using a kinetic ELISA. A survey administered at the time of sampling recorded information on housing, animal species present, manure management, reproduction, biosecurity practices, wildlife observations, peri-parturient cow management, herd disease history and nutrition. Production and other herd parameters were obtained from DHI records. Logistic regression indicated that the following parameters were positively associated with a N. caninum abortion in a herd: the N. caninum herd seroprevalence (OR = 1.1), the total number of dogs on a farm (OR = 2.8), the frequency that dogs were observed defecating in mangers (OR = 2.8), the number of horses on a farm (OR = 3.1), the observed annual rate of retained fetal membranes (OR = 1.2) and the observed annual rate of cows returning to estrus after pregnancy confirmation (OR = 1.2). Factors negatively associated were the frequency of stray cats and wild canids observed on a farm (OR = 0.4 and OR = 0.7, respectively) and the housing of heifers on loafing packs (a housing pen divided into feed manger, scrape alley and bedded pack areas, OR = 0.1).