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OBJECTIVE: To investigate the outcomes from ipsilateral simultaneous or sequential cochlear implantation in patients with neurofibromatosis type 2 (NF2) after vestibular schwannoma removal with cochlear nerve preservation. STUDY DESIGN: Retrospective case series. SETTING: Single tertiary referral NF2 center. PATIENTS: Six patients with NF2. INTERVENTION: Removal of vestibular schwannoma (VS) with preservation of the cochlear nerve and cochlear implantation. Four patients had their surgery via a translabyrinthine approach. Two patients had a retrosigmoid approach. A cochlear implant was inserted at the same time as tumor removal in 4 cases and sequentially in 2 cases. MAIN OUTCOME MEASURES: Surgical and audiometric outcomes using Bamford-Kowal-Bench (BKB) and City of New York University (CUNY) sentence scores. RESULTS: The average age at implantation was 24 years (range, 15-36 yr). Follow-up ranged from 5 to 93 months, with an average of 38 months. All patients had useful hearing in the contralateral ear before surgery. One patient gained no benefit from cochlear implantation and proceeded to have an auditory brainstem implant. Of those that had functional cochlear nerves, the average BKB score in quiet was 64%, BKB score in noise was 42%, and CUNY score with lipreading was 97%. Results varied within the group, but all patients gained significant benefit and continue to use their CI at least intermittantly. CONCLUSION: The present series demonstrates that in selected cases, cochlear implantation can be successful after a translabyrinthine approach for VS removal and for restoring hearing after failed retrosigmoid hearing preservation surgery. All patients found the cochlear implant offered useful hearing even in the presence of contralateral hearing.

OBJECTIVE: Hearing loss resulting from bilateral vestibular schwannomas (VSs) has a significant effect on the quality of life of patients with neurofibromatosis Type 2 (NF2). A national consensus protocol was produced in England as a guide for cochlear implantation (CI) and auditory brainstem implantation (ABI) in these patients. STUDY DESIGN: Consensus statement. SETTING: English NF2 Service. PARTICIPANTS: Clinicians from all 4 lead NF2 units in England. MAIN OUTCOME MEASURES: A protocol for the assessment, insertion and rehabilitation of CI and ABI in NF2 patients. RESULTS: Patients should undergo more detailed hearing assessment once their maximum aided speech discrimination score falls below 50% in the better hearing ear. Bamford-Kowal-Bench sentence testing scores below 50% should trigger assessment for auditory implantation, as recommended by the National Institute for Clinical Excellence guidelines on CI. Where this occurs in patients with bilateral stable VS or a unilateral stable VS where the contralateral cochlear nerve was lost at previous surgery, CI should be considered. Where VS surgery is planned, CI should be considered where cochlear nerve preservation is thought possible, otherwise an ABI should be considered. Intraoperative testing using electrically evoked auditory brainstem responses or cochlear nerve action potentials may be used to determine whether a CI or ABI is inserted. CONCLUSION: The NF2 centers in England agreed on this protocol. Multisite, prospective assessments of standardized protocols for auditory implantation in NF2 provide an essential model for evaluating candidacy and outcomes in this challenging patient population.

The legal environment is one factor that influences injection drug users’ (IDUs) risk for HIV and other bloodborne pathogens such as hepatitis C virus (HCV). We examined the association between law enforcement encounters (i.e., arrests and citations) and receptive syringe sharing among IDUs in the context of an intensified policing effort. We conducted a mixed methods analysis of 30 qualitative and 187 quantitative interviews with IDUs accessing services at a Los Angeles, CA syringe exchange program from 2008 to 2009. Qualitative findings illustrate concerns related to visibility, drug withdrawal, and previous history of arrest/incarceration. In quantitative analysis, the number of citations received, current homelessness, and perceiving that being arrested would be a “big problem” were independently associated with recent syringe sharing. Findings illustrate some of the unintended public health consequences associated with intensified street-level policing, including risk for HIV and HCV transmission.

To analyse the long-term outcome of translabyrinthine surgery for vestibular schwannoma (VS) in neurofibromatosis type 2 (NF2). RESEARCH TYPE: Retrospective cohort study.Two tertiary referral NF2 units.One hundred and forty eight translabyrinthine operations for patients with VS were performed. Preoperative stereotactic radiotherapy had been performed on 12(9.4%) patients.Mean tumour size was 3.1 cm. Total tumour excision was achieved in 66% of cases, capsular remnants were left in 24% of cases, and subtotal excision was achieved in 5% and partial removal was achieved in 5%. The radiological residual/recurrence rate was 13.9%. The perioperative mortality was 1.6%. At 2 years postoperatively, facial function was expressed in terms of House-Brackmann score (HB): HB 1 in 53.4%, HB 1/2 in 61.3%, HB 1-3 in 83.2% and HB 4-6 in 16.8%. All nine patients who underwent surgery following failed stereotactic radiotherapy had HB 3 function or better. Among 9.5% of the cases, 14 facial nerves were lost during surgery and repaired using direct anastomosis or grafting. There was no tinnitus present preoperatively in 27% of the cases, and 22% of patients developed tinnitus postoperatively. In patients with preoperative tinnitus, 61% remained the same, 17% got it resolved and only in 21% it worsened. The preoperative hydrocephalus rate was 26%, and among 15% of the cases five ventriculo-peritoneal (VP) shunts were performed. The cerebrospinal fluid leak rate was 2.5%. Fifty-six patients underwent auditory brainstem implantation (ABI) and two patients had cochlear implant (CI) sleepers inserted.The management of patients with NF2 presents the clinician with a formidable challenge with many patients still presenting themselves late with the neurological compromise and a large tumour load. There is still an argument for the management by observation until the neurological compromise dictates interventional treatment particularly with the option of hearing rehabilitation with ABI or CI. The translabyrinthine approach provides a very satisfactory means of reducing the overall tumour volume.

It is a remarkable coincidence that we have been asked to write this article now as it is exactly ten years ago this month (November, at time of writing) that the first tentative steps that led to the development of Perspective occurred.

Sound is the most efficient radiation in the ocean. Sounds of seismic and biological origin contain information regarding the underlying processes that created them. A single hydrophone records summary time-frequency information from the volume within acoustic range. Beamforming using a hydrophone array additionally produces azimuthal estimates of sound sources. A two-dimensional array and acoustic focusing produce an unambiguous two- dimensional `image' of sources. This dissertation describes the application of these techniques in three cases. The first utilizes hydrophone arrays to investigate T-phases (water-borne seismic waves) in the Philippine Sea. Ninety T-phases were recorded over a 12-day period, implying a greater number of seismic events occur than are detected by terrestrial seismic monitoring in the region. Observation of an azimuthally migrating T-phase suggests that reverberation of such sounds from bathymetric features can occur over megameter scales. In the second case, single hydrophone recordings from coral reefs in the Line Islands archipelago reveal that local ambient reef sound is spectrally similar to sounds produced by small, hard-shelled benthic invertebrates in captivity. Time- lapse photography of the reef reveals an increase in benthic invertebrate activity at sundown, consistent with an increase in sound level. The dominant acoustic phenomenon on these reefs may thus originate from the interaction between a large number of small invertebrates and the substrate. Such sounds could be used to take census of hard-shelled benthic invertebrates that are otherwise extremely difficult to survey. A two-dimensional 'map' of sound production over a coral reef in the Hawaiian Islands was obtained using two-dimensional hydrophone array in the third case. Heterogeneously distributed bio-acoustic sources were generally co-located with rocky reef areas. Acoustically dominant snapping shrimp were largely restricted to one location within the area surveyed. This distribution of sources could reveal small-scale spatial ecological limitations, such as the availability of food and shelter. While array-based passive acoustic sensing is well established in seismoacoustics, the technique is little utilized in the study of ambient biological sound. With the continuance of Moore's law and advances in battery and memory technology, inferring biological processes from ambient sound may become a more accessible tool in underwater ecological evaluation and monitoring

Auricular petrification is a rare diagnosis and presents an interesting therapeutic challenge. Fewer than 160 cases have been reported in the literature since the first description by Bochdalek in 1866. The most common etiology is ectopic calcification. It may also result from injurious processes including frostbite, physical trauma, inflammatory conditions, and various endocrinopathies. We report an incidental finding of idiopathic bilateral auricular petrification in a 40-year-old man presenting with idiopathic unilateral sensorineural deafness.

US practitioners should be aware of the characteristic appearance of testicular lipomatosis to prevent misdiagnosis of a more sinister disease; the radiologist may be the first to suggest a diagnosis of Cowden disease.

Objective:To investigate the frequency of vascular risk factors in unilateral idiopathic sudden sensorineural hearing loss (ISSHL) in young adults.Materials and Methods:Twenty patients aged 18-50 years when suffering a unilateral ISSHL and 20 age and sex matched controls were examined with contrast-enhanced transcranial doppler to identify venous to arterial circulation shunts (v-aCS), flow mediated dilation of the brachial artery to identify endothelial dysfunction and blood tests for a thrombophilia screen, full blood count, fasting plasma lipids, p-selectin and soluble glycoprotein V.Results:There were no significant differences between cases and controls for any of the investigations performed. There was no difference at all between the larger (“significant” or “major”) v-aCS and ISSHL (25% vs 25%). There was a limited association for “small” v-aCS with ISSHL (35% vs 25%; p=0.77); between the presence of v-aCS and severity of hearing loss (no v-aCS 49.0+/- 26 dBHL vs v-aCS 73.4 +/- 34dBHL, p=0.11); for endothelial dysfunction with ISSHL (5.9 +/- 3.2% vs 7.2 +/- 3.2%; p=0.32); and for platelet hypereactivity with ISSHL (glycoprotein V: 67.0+/-22.3ng/ml vs 64.2+/-21.5ng/ml, p=0.605; p-selectin: 81.7+/-40.2ng/ml vs 75.8+/-45.6ng/ml, p=0.590). Only 1 case had an inherited thrombophilia compared with 2 controls. No cases had positive antiphospholipid antibodies. High fibrinogen levels were more prevalent in cases: two cases and one control had hyperfibrinogenaemia with a further 5 cases and 4 controls in the upper quartile range. Hyperlipidaemia was more prevalent in controls.Conclusions:Paradoxical embolism and venous thrombosis are unlikely to be important causes of unilateral ISSHL in young adults. Mildly raised cardiovascular arterial risk factors such as endothelial dysfunction, hyperfibrinogenaemia and p-selectin suggest a possible vascular dysfunction in these patients that may warrant further study. The cause of ISSHL remains a mystery.

Background Meningiomas have been reported to occur in approximately 50% of neurofibromatosis type 2 (NF2) patients. The NF2 gene is commonly biallelically inactivated in both schwannomas and meningiomas. The spectrum of NF2 mutations consists mainly of truncating (nonsense and frameshift) mutations. A smaller number of patients have missense mutations, which are associated with a milder disease phenotype. Methods This study analysed the cumulative incidence and gender effects as well as the genotype–phenotype correlation between the position of the NF2 mutation and the occurrence of cranial meningiomas in a cohort of 411 NF2 patients with proven NF2 mutations. Results and Conclusion Patients with mutations in exon 14 or 15 were least likely to develop meningiomas. Cumulative risk of cranial meningioma to age 50 years was 70% for exons 1–3, 81% for exons 4–6, 49% for exons 7–9, 56% for exons 10–13, and 28% for exons 14–15. In the cohort of 411 patients, no overall gender bias was found for occurrence of meningioma in NF2 disease. Cumulative incidence of meningioma was close to 80% by 70 years of age for both males and females, but incidence by age 20 years was slightly increased in males (male 25%, female 18%; p=0.023). Conversely, an increased risk of meningiomas in women with mosaic NF2 disease was also found.

To retrospectively evaluate the midterm outcome of patients treated for primary renal cell carcinomas arising in kidney transplants with minimally invasive techniques.The institutional review board of each participating institution approved this retrospective study and waived informed consent. This study was HIPAA compliant. A request for cases through the European Society of Urogenital Radiology network was made to institutions for patients who fit the requirements outlined by the authors, and a prospective follow-up of recipients was performed. Twenty-four tumors were identified that developed in the renal allograft of 20 patients from 11 institutions who were treated with radiofrequency ablation (n = 19) or cryoablation (n = 5) between 2003 and 2010. Maximal diameter of masses was 6-40 mm (median, 19.5 mm). Twenty masses were solid, and four were type 4 cystic masses. Preablation biopsy was performed for solid tumors only. All images and biologic and biopsy reports were retrospectively reviewed. Significant differences were determined by using a paired t test before and after ablation.Mean follow-up was 27.9 months (range, 7-71 months). Histopathologic examination revealed papillary carcinoma in 17 patients and clear cell carcinoma in three. Tumors were successfully treated with ultrasonographic guidance in six patients, with computed tomographic guidance in 10 patients, and with both in four patients. One case of infection of the tumor site and one case of transitory genitofemoral nerve injury were the only reported complications. No significant change of renal function was noted. Subsequent imaging follow-up did not reveal any case of recurrence in the ablative site.Percutaneous thermal ablation of renal tumors occurring in renal grafts is effective, with low morbidity. .

The pathological and radiological hallmarks of multiple sclerosis (MS) include multiple demyelinated lesions disseminated throughout the white matter of the central nervous system (CNS). More recently, the cerebral cortex has been shown to be affected in MS, but the elucidation of events causing cortical demyelination has been hampered by the lack of animal models reflecting such human cortical pathology. In this report, we have described the presence of cortical gray matter and callosal white matter demyelinating lesions in the chronic experimental autoimmune encephalomyelitis (EAE) mouse model of MS. Similar to the pathological lesions of MS patients, EAE lesions have been classified as type I-leukocortical, type II-intracortical and type III-subpial. All of these lesions had varying degrees of demyelination, inflammatory cells and reactive astrocytes. Similar to MS, cortical layers during EAE showed demyelination, microglia activation, synaptic protein alterations and apoptotic cells. In addition, the callosal white matter during EAE had many inflammatory demyelinating lesions and axon degeneration. Functional electrophysiological conduction analysis showed deficits in both myelinated and unmyelinated callosal axons during early and late EAE. The chronic EAE mouse model has features that mimic cortical and callosal pathology of MS, and can be potentially used to screen agents to prevent these features of disease.

Pancreatic splenosis is a very rare condition whose features on contrast-enhanced ultrasound (CEUS) have not, to our knowledge, been previously reported. We present the imaging findings in a case of pancreatic splenosis, in which a confident diagnosis was achieved with the use of CEUS and confirmed by a labeled heat denatured red cell scan. Accumulation of ultrasound contrast microbubbles in splenic tissue can be readily visualized on late-phase CEUS and this technique has already been used to confirm the nature of intrapancreatic accessory spleens. This case shows that it can also confirm the diagnosis of splenosis.