Characteristics, management and outcome of a large necrotising otitis externa case series: need for standardised case definition.

BACKGROUND: Necrotising otitis externa is a severe ear infection for which there are no established diagnostic or treatment guidelines. METHOD: This study described clinical characteristics, management and outcomes for patients managed as necrotising otitis externa cases at a UK tertiary referral centre. RESULTS: A total of 58 (63 per cent) patients were classified as definite necrotising otitis externa cases, 31 (34 per cent) as probable cases and 3 (3 per cent) as possible cases. Median duration of intravenous and oral antimicrobial therapy was 6.0 weeks (0.49-44.9 weeks). Six per cent of patients relapsed a median of 16.4 weeks (interquartile range, 23-121) after stopping antimicrobials. Twenty-eight per cent of cases had complex disease. These patients were older (p = 0.042), had a longer duration of symptoms prior to imaging (p < 0.0001) and higher C-reactive protein at diagnosis (p = 0.005). Despite longer courses of intravenous antimicrobials (23 vs 14 days; p = 0.032), complex cases were more likely to relapse (p = 0.016). CONCLUSION: A standardised case-definition of necrotising otitis externa is needed to optimise diagnosis, management and research.

Electron localisation in static and time-dependent one-dimensional model systems.

The most direct signature of electron localisation is the tendency of an electron in a many-body system to exclude other same-spin electrons from its vicinity. By applying this concept directly to the exact many-body wavefunction, we find that localisation can vary considerably between different ground-state systems, and can also be strongly disrupted, as a function of time, when a system is driven by an applied electric field. We use this measure to assess the well-known electron localisation function (ELF), both in its approximate single-particle form (often applied within density-functional theory) and its full many-particle form. The full ELF always gives an excellent description of localisation, but the approximate ELF fails in time-dependent situations, even when the exact Kohn-Sham orbitals are employed.

Controversies in the management of caustic ingestion injury: an evidence-based review.

BACKGROUND: Caustic ingestion of acid or alkaline substances can cause damage to the upper respiratory and upper digestive tract. Initial presentation following caustic ingestion can include oropharyngeal pain, dysphagia and stridor. It is due to this clinical presentation that the resident otolaryngologist is consulted to review and examine these patients to assess for airway compromise and commence initial management and care until airway concern has passed. OBJECTIVE OF REVIEW: This review aims to provide evidence-based guidance in the management of those presenting with acute ingestion injury so that informed initial medical therapy can be commenced and appropriate investigations are arranged to optimize patient outcome. TYPE OF REVIEW AND SEARCH STRATEGY: A literature review searched PubMed citing variations on the areas of controversies with 'caustic ingestion', 'corrosive ingestion', 'acid ingestion' and 'alkali ingestion' - from 1956 to present with language restrictions. EVALUATION METHOD: The bibliographies of articles were searched for relevant references. The references were then compiled and reviewed independently by two authors (JB and SK), overseen by the senior authors (CP and JR). The review process was conducted independently, with the results then collated, with the aim of identifying the highest levels of evidence in each of the areas of controversy. RESULTS: Over 100 full-text articles were retrieved. Several specific areas of controversy were identified and addressed, with the highest available evidence referenced for each area. CONCLUSIONS: In caustic ingestion injury, the urgent assessment of the airway is the first priority with a definitive airway secured in those with airway compromise. In those patients with a stable airway and no clinical or radiological sign of perforation, then medical therapy should be commenced and an urgent oesophagogastroduodenoscopy (OGD) is arranged and this should take place within the first 24 h to grade the degree of injury and establish long-term prognosis. In suspected perforation, a surgical opinion should be sought. For those adults who are asymptomatic following ingestion an OGD may not be necessary; however, asymptomatic paediatric patients should be treated with more caution and a period of observation is important. Those who are at risk of developing late complications must be followed up.

Pete's bar: alternative use of the laryngoscopy suspension bar to improve surgical exposure during small incision cochlear implantation.

BACKGROUND: Cochlear implant surgery is increasingly being performed through a small incision because of the benefits associated with this technique, such as fewer wound complications. Efforts have been made to maximise surgical exposure in order to improve this evolving technique; this includes the development and use of new retractors. For instance, elasticated stay hooks can retract skin in a radial fashion and they are less bulky than traditional retractors. These hooks are usually attached directly to surgical drapes or to a disposable retractor ring; there are disadvantages to both of these methods. METHOD: This paper describes a technique using a laryngeal suspension bar in which the bar acts as a fixed structure to which these elasticated stay hooks can be attached. CONCLUSION: This technique was found to be safer, cheaper and more effective for obtaining optimal surgical exposure compared with a technique whereby the stay hooks are attached directly to the drapes or to a disposable retractor ring.

A UK experience of daycase cochlear implant surgery.

OBJECTIVES: This study aims to assess the safety of daycase cochlear implant surgery. METHODS: A retrospective review was conducted on all patients who underwent cochlear implant surgery at a teaching hospital in Oxford, UK between September 2008 and February 2012. RESULTS: One hundred and sixteen patients underwent cochlear implant surgery. This included 73 adults and 43 children. Twenty-six patients underwent the procedure as a daycase procedure. There were no readmissions. DISCUSSION: The demand 'to do more with less' has led to increasing drives for efficiency and cost-effectiveness. Therefore, the role of daycase surgery is becoming increasingly widespread. Daycase surgery has been shown to be advantageous for both patients and hospitals. CONCLUSION: Daycase cochlear implant surgery is feasible and can be safely conducted in a select group of patients.

Exact density-functional potentials for time-dependent quasiparticles.

We calculate the exact Kohn-Sham potential that describes, within time-dependent density-functional theory, the propagation of an electron quasiparticle wave packet of nonzero crystal momentum added to a ground-state model semiconductor. The potential is observed to have a highly nonlocal functional dependence on the charge density, in both space and time, giving rise to features entirely lacking in local or adiabatic approximations. The dependence of the nonequilibrium part of the Kohn-Sham electric field on the local current and charge density is identified as a key element of the correct Kohn-Sham functional.

Susac syndrome: outcome of unilateral cochlear implantation.

OBJECTIVE: Susac syndrome comprises a triad of vestibulocochlear dysfunction, retinopathy and multifocal encephalopathy, which is characterised pathophysiologically by microangiopathy of the ear, retina and brain. Diagnosis is confirmed by magnetic resonance imaging of the brain and ophthalmological examination, which reveals branch retinal artery occlusion. Hearing loss persists in 90 per cent of patients. We present a case of successful hearing rehabilitation by cochlear implantation in a young woman with this syndrome. CLINICAL PRESENTATION: A 36-year-old woman presented with neurological symptoms suggestive of encephalitis. She subsequently developed vestibulocochlear symptoms. The diagnosis was confirmed upon magnetic resonance imaging and fluorescein angiography, which showed multiple peripheral retinal arterial occlusions. Hearing loss was fluctuant but gradually progressive over nine months, to bilateral profound sensorineural hearing loss. INTERVENTION: A left cochlear implant was placed, with a good outcome. CONCLUSION: In this Susac syndrome patient, the outcome of cochlear implantation was encouraging, notwithstanding the possible involvement of retrocochlear pathways.

Multiple effects of childhood deafness on cortical activity in children receiving bilateral cochlear implants simultaneously.

OBJECTIVE: Auditory development is disrupted without normal hearing but might proceed to some extent depending on the type and onset of deafness. We therefore hypothesized that activity in the auditory cortex would be highly variable in children who are deaf. METHODS: To answer this, activity in the deaf brain was evoked by electrical pulses from newly provided bilateral cochlear implants (CIs) in 72 children (n=144 responses). RESULTS: Responses were categorized by visual inspection into 3 main types which were validated by principal component cluster analyses; 49% had a negative amplitude wave similar to that previously reported in pre-term infants, 26% were dominated by a positive peak typical of responses in young normal hearing children and experienced paediatric CI users, 25% were novel multi-peaked responses. No significant demographic differences, including duration and onset of deafness, were found between response types. However, children with severe biallelic mutations of GJB-2 showed predominately negative peak type responses (79%) as compared with their peers without these mutations who had a more equal distribution between cortical response types. CONCLUSION: Cortical development in children who are deaf is heterogeneous but can be better predicted when the genotype is known to be a GJB-2 mutation. SIGNIFICANCE: Remediation of childhood deafness seeks to restore normal development and function of central auditory functions and thus may need to be tailored to account for effects specific to the aetiology of deafness.

Langerhans' cell histiocytosis of the temporal bone: successful treatment of sensorineural hearing loss with low-dose radiotherapy.

OBJECTIVE: To present the successful treatment of sensorineural hearing loss secondary to Langerhans' cell histiocytosis with low-dose radiotherapy, and also the disparity between radiological resolution of Langerhans' cell histiocytosis lesions and lack of sensorineural hearing loss improvement, accompanied by a review of the literature on otolaryngological manifestations and management of Langerhans' cell histiocytosis. CASE REPORT: Langerhans' cell histiocytosis is a multisystem disease which frequently causes osseous lesions in the temporal bones. Hearing loss is usually conductive but may be sensorineural with lesions of the petrous temporal bone. We present a case of sensorineural hearing loss secondary to Langerhans' cell histiocytosis affecting the labyrinth and internal auditory meatus, which resolved following radiotherapy. Contralateral sensorineural hearing loss in the same patient, previously treated with chemotherapy, did not resolve despite radiological resolution of the temporal bone lesions. CONCLUSION: We suggest that timely radiotherapy for treatment of sensorineural hearing loss secondary to Langerhans' cell histiocytosis is an appropriate treatment option.

B-cell lymphoma of the larynx in a patient with rheumatoid arthritis.

We report a case of B-cell lymphoma with the larynx as the primary site of presentation in a rheumatoid arthritis patient previously treated with methotrexate. Primary non-Hodgkin's lymphoma (NHL) of the larynx is rare. There may be an increased risk of lymphoma in patients with rheumatoid arthritis, with an even higher risk in those patients treated with methotrexate. The diagnostic and treatment options are discussed.

Who performs thyroid surgery: a review of current otolaryngological practice.

Thyroid surgery has been traditionally a general surgical practice, but recently more otolaryngologists have been offering a thyroid service. We have quantified thyroid surgery performed by the different specialties, and looked more closely at the practice of otolaryngologists. Data was obtained from the Department of Health for UK thyroid surgery in all specialties for the year 1998-99 and validated against a survey of members of the British Association of Otolaryngologists-Head & Neck Surgeons (BAO-HNS). The use of investigations of a simple clinical case (solitary thyroid nodule) was compared with best practice. General surgeons still perform the majority of thyroid surgery (83%) but ENT surgeons now perform significant numbers (15.4% of all cases), which translates to 1499 cases per annum. A total of 102 BAO-HNS members were performing thyroid surgery with an average case-load of 19.1 per year. In total, 35% of ENT surgeons see thyroid patients in multidisciplinary clinics. The choice of investigation is consistent with European guidelines. ENT surgeons are doing significant amounts of thyroid surgery and the numbers appear to be increasing. The formation of multidisciplinary teams including general surgeons and otolaryngologists who are committed to subspecialization can only improve both training and treatment outcomes.

Thyroid follicular cells secrete plasminogen activators and can form angiostatin from plasminogen.

Angiostatin, a 38 kDa fragment of plasminogen, potently inhibits the growth of blood vessels. Angiostatin is generated from plasminogen by urokinase-type (uPA) and tissue-type (tPA) plasminogen activators in the presence of free sulphydryl donors. Angiogenesis inhibitors may be important in regulating angiogenesis in developing goitre. We have examined angiostatin formation in human primary thyrocyte cultures and a rat thyrocyte cell line (FRTL-5). We found that human thyroid cells in culture secrete plasminogen activators (both tPA and uPA) as well as matrix metalloproteinase 2 into the medium. When human thyrocyte conditioned medium was incubated with plasminogen (10 microg/ml) and N-acetylcysteine (100 microM) for 24 h, a 38 kDa fragment of plasminogen, which is consistent with angiostatin, was generated. The appearance of the 38 kDa fragment was increased by agents that increase cAMP (forskolin and 8 BrcAMP). FRTL-5 cells, which do not secrete uPA or tPA, did not generate angiostatin. Thyroid cells produce several angiogenic growth factors, and human thyrocyte conditioned medium stimulated growth of endothelial cells. When the conditioned medium was incubated with plasminogen and N-acetylcysteine, this stimulatory effect was lost, consistent with the production of a growth inhibitory factor. We conclude that thyroid cells can produce angiostatin from plasminogen in vitro, and this may play a role in vivo in limiting goitre size.

Tie-2 is expressed on thyroid follicular cells, is increased in goiter, and is regulated by thyrotropin through cyclic adenosine 3',5'-monophosphate.

Angiogenesis is coordinated with follicular cell growth in goitrogenesis. The angiopoietins, Ang-1 and Ang-2, are angiogenic growth factors acting through Tie-2, a tyrosine kinase receptor. We have examined the expression and regulation of the angiopoietins and Tie-2 in human and rat thyroids. In human goiters there was increased Tie-2 immunostaining, compared with that in normal thyroids, on both follicular and endothelial cells. In an induced goiter in rats, in situ hybridization showed increased expression of messenger ribonucleic acids (mRNAs) for Tie-2 and Ang-1 in follicular cells. As Tie-2 has previously been believed to be restricted to cells of endothelial lineage in adults, we examined its expression further in isolated follicular cells. Tie-2 and Ang-1 mRNA expression in human thyrocytes was confirmed by ribonuclease protection assay. Ang-2 mRNA was not detected in human cultures or rat thyroids. In both human follicular cell cultures and FRTL-5 cells, immunoblotting showed that Tie-2 expression was increased by TSH and agents that increased intracellular cAMP. In conclusion, we have demonstrated the expression of Tie-2 and Ang-1 in thyroid epithelial and endothelial cells, and have shown the regulation of Tie-2 by TSH and cAMP in follicular cells. Tie-2 expression is increased in goiter in both humans and rats, consistent with a role in goitrogenesis.

Angiogenesis in the thyroid gland.

Angiogenesis is the mechanism of blood vessel formation after the first few days of embryogenesis, and is essential for all tissue growth. In adults, angiogenesis occurs in the thyroid during disease processes including goitre, Graves' disease, thyroiditis and cancer. The molecular mechanisms controlling angiogenesis are becoming clearer, and therapy targeting these processes is coming closer to clinical fruition. Both promoters and inhibitors of angiogenesis have been identified in the thyroid, including vascular endothelial growth factor (VEGF), fibroblast growth factor, and thrombospondin. This commentary will review the understanding of the control of angiogenesis within the context of the thyroid gland, and review the pre-eminent role of VEGF as the angiogenic signal from the follicular cells to the endothelial cells.

Bilateral cerebrospinal fluid rhinorrhoea.

Cerebrospinal fluid (CSF) rhinorrhoea is leakage of fluid from the subarachnoid space to the frontal, sphenoidal or ethmoidal sinuses, and may occur spontaneously. The authors present the first reported case of bilateral spontaneous CSF rhinorrhoea. Bony defects on both sides of the cribriform plate were identified using endoscopic and radiological techniques, and the CSF fistula was closed endoscopically. The aetiology, diagnosis and contemporary surgical treatment of spontaneous CSF leaks is discussed. Endoscopic repair was successful in this case, and in view of the high success and low reported complication rates this surgical approach should be considered for treatment of spontaneous CSF rhinorrhoea.