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BACKGROUND: Neurofibromatosis Type 2 (NF2) is a dominantly inherited tumour syndrome with a phenotype which includes bilateral vestibular (eighth cranial nerve) schwannomas. Conventional thinking suggests that these tumours originate at a single point along the superior division of the eighth nerve. METHODS: High resolution MRI was performed in children genetically proven to have NF2. The superior vestibular nerve (SVN) and inferior vestibular nerve (IVN) were visualised along their course with points of tumour origin calculated as a percentage relative to the length of the nerve. RESULTS: Out of 41 patients assessed, 7 patients had no identifiable eighth cranial nerve disease. In 16 patients there was complete filling of the internal auditory meatus by a tumour mass such that its specific neural origin could not be determined. In the remaining 18 cases, 86 discrete separate foci of tumour origin on the SVN or IVN could be identified including 23 tumours on the right SVN, 26 tumours on the right IVN, 18 tumours on the left SVN and 19 tumours on the left IVN. DISCUSSION: This study, examining the origins of vestibular schwannomas in NF2, refutes their origin as being from a single site on the transition zone of the superior division of the vestibular nerve. We hypothesise a relationship between the number of tumour foci, tumour biology and aggressiveness of disease. The development of targeted drug therapies in addition to bevacizumab are therefore essential to improve prognosis and quality of life in patients with NF2 given the shortcomings of surgery and radiation treatments when dealing with the multifocality of the disease.

Aim To assess the long-term subjective benefits of auditory brainstem implants (ABIs) and investigate the extent to which ABI users perceive it to be a useful device. Methods Using the Manchester database, all 31 living patients registered as ABI users were identified and sent the ABI performance questionnaire. Data regarding daily duration of use, auditory fatigue, ability to differentiate between speech and environmental sounds, and subjective usefulness of the ABI in different listening conditions were collected. Patients were asked to rate the usefulness of the device in various settings on a scale of 1 (not useful) to 6 (very useful). The mean age at implantation was 33 years (13-73 yr), and the mean follow-up period was 6 years (1.5-15 yr). Results Between March 1994 and September 2009, 57 patients underwent ABI insertion. A total of 26 patients were not eligible for inclusion in the study (19 nonusers, 5 deceased, and 2 sleepers). Of the 31 eligible patients identified as ABI users, 23 returned the questionnaire, 1 was excluded as the questionnaire had been completed on his or her behalf, giving a net response rate of 71%. Mean duration of usage per day was 12.62 hours (range, 8-16 h). Seventy-one percent of the patients turned the processor off at one or more points during the day. Differentiation between speech and environment was achieved in 95%, and 70% were able to differentiate between gender and adult and pediatric voices. The ABI was perceived as most beneficial when dealing with a familiar voice in a quiet place, with a median usefulness score of 4, rising to 5 when used in conjunction with lip reading. The ABI was least useful when dealing with an unfamiliar voice in a loud place, with a mean score of 1, rising to 2 when used in conjunction with lip reading. In all environments, combining the ABI with lip reading served to increase usefulness ratings by at least 1 point. Conclusion This study demonstrates that ABI users make use of their device for at least 12 hours per day on average and obtain considerable subjective benefit in speech discrimination when using the device with familiar speakers in a quiet environment. Benefit is less significant in noise and with an unfamiliar speaker. Lip reading enhances subjective benefit by at least 1 point, and lip reading training may have a role to play in maximizing subjective benefit.

OBJECTIVE: To determine differences in speech perception outcomes for patients who received a CI422 and a Contour cochlear implant. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: Thirty-two adults who underwent cochlear implantation. INTERVENTION: Cochlear implantation using a CI422 or Contour device. MAIN OUTCOME MEASURE: Bamford-Kowal-Bench (BKB) speech perception scores at 3 and 9 months after activation. RESULTS: The mean BKB scores at 3 months for the CI422 device were 86.0% in quiet and 55.1% in noise. This compares with 86.0% in quiet and 62.3% in noise for the Contour device. At 9 months, the mean BKB scores were 85.9% in quiet and 67.1% in noise for the CI422 and 90.1% in quiet and 77.6% in noise for the Contour device. There was no statistically significant difference (p > 0.05) between speech perception outcomes at 3 or 9 months. CONCLUSION: This study suggests that CI422 and Contour electrode both improve speech perception outcomes postoperatively, and there does not appear to be any significant difference in outcome between the two types of devices.

Approximately 2% of congenital profound deafness cases are due to cochlear nerve (CN) deficiency. MRI is essential to confirm if the nerve is deficient, but because of limitations with resolution, especially when the internal auditory canal is narrowed, it is often unable to distinguish between hypoplasia and aplasia. A full audiometric test battery should always be performed, even if the MRI suggests CN aplasia, as there will sometimes be evidence of audition. Electrically evoked auditory brainstem response testing can be carried out transtympanically via the round window or using an intracochlear test electrode to help determine the status of the CN. If any test suggests the presence of a CN, then cochlear implantation (CI) should be considered. Children should be followed up closely with audiometric, electrophysiological and language assessments to determine the benefits. They may initially show benefit but fail to progress. CI results are variable and often result in poor outcomes with Categories of Auditory Perception scores of

The updated version of the EFSUMB guidelines on the application of non-hepatic contrast-enhanced ultrasound (CEUS) deals with the use of microbubble ultrasound contrast outside the liver in the many established and emerging applications.

Magnetic resonance imaging (MRI) of the scrotum represents a useful supplemental imaging technique in the characterization of scrotal masses, particularly recommended in cases of nondiagnostic ultrasonographic findings. An accurate characterization of the benign nature of scrotal masses, including both intratesticular and paratesticular ones may improve patient management and decrease the number of unnecessary radical surgical procedures. Alternative treatment strategies, including follow-up, lesion biopsy, tumor enucleation, or organ sparing surgery may be recommended. The aim of this pictorial review is to present how MRI helps in the characterization of sonographically indeterminate scrotal masses and to emphasize the key MRI features of benign scrotal masses.

The updated version of the EFSUMB guidelines on the application of non-hepatic contrast-enhanced ultrasound (CEUS) deals with the use of microbubble ultrasound contrast outside the liver in the many established and emerging applications.Die aktualisierte Version der EFSUMB-Leitlinien für die Anwendung von nicht-hepatischem kontrastverstärktem Ultraschall (CEUS) befasst sich mit der Verwendung von Mikrobläschen Ultraschall-Kontrastmitteln außerhalb der Leber in zahlreichen etablierten und neu entstehenden Einsatzbereichen.

A seven element, bi-linear hydrophone array was deployed over a coral reef in the Papahãnaumokuãkea Marine National Monument, Northwest Hawaiian Islands, in order to investigate the spatial, temporal, and spectral properties of biological sound in an environment free of anthropogenic influences. Local biological sound sources, including snapping shrimp and other organisms, produced curved-wavefront acoustic arrivals at the array, allowing source location via focusing to be performed over an area of 1600 m(2). Initially, however, a rough estimate of source location was obtained from triangulation of pair-wise cross-correlations of the sound. Refinements to these initial source locations, and source frequency information, were then obtained using two techniques, conventional and adaptive focusing. It was found that most of the sources were situated on or inside the reef structure itself, rather than over adjacent sandy areas. Snapping-shrimp-like sounds, all with similar spectral characteristics, originated from individual sources predominantly in one area to the east of the array. To the west, the spectral and spatial distributions of the sources were more varied, suggesting the presence of a multitude of heterogeneous biological processes. In addition to the biological sounds, some low-frequency noise due to distant breaking waves was received from end-fire north of the array.

Ultrasound is an invaluable tool in the diagnosis and management of many urological disorders. It has the advantages of not involving ionizing radiation, allowing rapid real time imaging and being relatively inexpensive. It can also be performed at the patient’s bedside if necessary. There are limitations, however, and it is best used as an adjunct to clinical assessment, often alongside other complementary imaging modalities. While many ultrasound studies are undertaken by urological surgeons, it is often performed by imaging specialists; close liaison between these two groups is essential. A brief, clinically relevant, introduction to ultrasound physics is included and the use of Doppler techniques and ultrasound contrast agents will be discussed. It is not possible to cover all the urological conditions for which ultrasound is used in one chapter, so some recommended texts are included in the reading list for further study.

Objective:To determine the specificity of the current clinical diagnostic criteria for neurofibromatosis type 2 (NF2) relative to the requirement for unilateral vestibular schwannoma (VS) and at least 2 other NF2-related tumors.Methods:We interrogated our Manchester NF2 database, which contained 205 individuals meeting NF2 criteria who initially presented with a unilateral VS. Of these, 83 (40.7%) went on to develop a contralateral VS. We concentrated our genetic analysis on a group of 70 who initially fulfilled NF2 criteria with a unilateral vestibular schwannoma and at least 2 additional nonintradermal schwannomas.Results:Overall, 5/70 (7%) individuals with unilateral VS and at least 2 other schwannomas had a pathogenic or likely pathogenic LZTR1 mutation. Twenty of the 70 subsequently developed bilateral disease. Of the remaining 50, 5 (10%) had a germline LZTR1 mutation, equivalent to the number (n = 5) with a germline NF2 mutation.Conclusions:The most common etiology for unilateral VS and 2 additional NF2-associated tumors in this cohort was mosaic NF2. Germline LZTR1 and germline NF2 mutations were equally common in our cohort. This indicates that LZTR1 must be considered when making a diagnosis of NF2 in the presence of unilateral VS in individuals without a germline NF2 mutation.

Transverse testicular ectopia is a rare congenital anomaly in which both testes migrate along the same inguinal canal toward the scrotum. This report describes the case of the rarest form of transverse testicular ectopia in a 23-year-old man with coexisting testicular microlithiasis in one of the two testes as diagnosed on sonography and confirmed on MRI. We are unaware of any previous published reports of this association. Although the etiology of both conditions is debatable, each is believed to be associated with an increased risk of testicular malignancy, and this poses a dilemma for the future management of this patient.

Although ambient biological underwater sound was first characterized more than 60 years ago, attributing specific components of ambient sound to their creators remains a challenge. Noise produced by snapping shrimp typically dominates the ambient spectra near tropical coasts, but significant unexplained spectral variation exists. Here, evidence is presented indicating that a discernible contribution to the ambient sound field over coral reef ecosystems in the Line Islands archipelago originates from the interaction of hard-shelled benthic macro-organisms with the coral substrate. Recordings show a broad spectral peak centered between 14.30 and 14.63 kHz, incoherently added to a noise floor typically associated with relatively "white" snapping shrimp sounds. A 4.6 to 6.2 dB increase of pressure spectral density level in the 11 to 17 kHz band occurs simultaneously with an increase in benthic invertebrate activity at night, quantified through time-lapse underwater photography. Spectral-level-filtered recordings of hermit crabs Clibanarius diugeti in quiet aquarium conditions reveal that transient sounds produced by the interaction between the crustaceans' carapace, shell, and coral substrate are spectrally consistent with Line Islands recordings. Coral reef ecosystems are highly interconnected and subtle yet important ecological changes may be detected quantitatively through passive monitoring that utilizes the acoustic byproducts of biological activity.

Ambient noise in very shallow water is often dominated by sound from biological sources. In addition to their economic and aesthetic value, coral reef environments are of interest acoustically due to their persistently loud biological ambient noise levels, relatively high biomass, diversity of soniferous organisms, and their relatively unique spatial nature in which the receiver is often surrounded by large numbers of transient sources, each emitting relevant information. Stemming from work in the Buckingham lab, our investigation of these sounds and their connection with biological processes continues through both directional and point receivers. This talk will discuss how information contained in the transient aspects of these sound fields can reveal the nature of the sources and physical mechanisms behind the generation of their sounds, spatial distribution of benthic communities, dynamic interactions between organisms and changes in the environment arising from human impacts such as the removal of herbivorous fishes.Ambient noise in very shallow water is often dominated by sound from biological sources. In addition to their economic and aesthetic value, coral reef environments are of interest acoustically due to their persistently loud biological ambient noise levels, relatively high biomass, diversity of soniferous organisms, and their relatively unique spatial nature in which the receiver is often surrounded by large numbers of transient sources, each emitting relevant information. Stemming from work in the Buckingham lab, our investigation of these sounds and their connection with biological processes continues through both directional and point receivers. This talk will discuss how information contained in the transient aspects of these sound fields can reveal the nature of the sources and physical mechanisms behind the generation of their sounds, spatial distribution of benthic communities, dynamic interactions between organisms and changes in the environment arising from human impacts such as the removal of her...

Biological sources contribute significantly to coral reef ambient noise environments, yet the ecosystem-level mechanisms of temporal and spatial variation in the reef soundscape are not well understood. In this study, subtle shifts in reef ambient noise are examined using unsupervised machine learning on hydrophone array data. Unsupervised learning does not require data labels, but uses nonlinear inference to find explanatory features within the data. A hydrophone array was used to generate spatially filtered time series inputs for machine learning. Video cameras were collocated and time-synced with the hydrophone array to provide nominal ground-truth. We discuss the tradeoff parameters of the unsupervised learning methods. Changes in the dominant data features during the experiment are compared to the video recordings and researcher observations.

Coral reefs are complicated and understudied acoustic propagation environments. In addition to geometric spreading, there are propagation losses due to bottom attenuation, volumetric scattering, and boundary scattering from bathymetric variability and sea surface roughness. On a Hawaiian coral reef, a field test was performed in shallow water during which low-level tones were projected from an underwater speaker and received by a single hydrophone at various ranges up to 500 m from the source. Acoustic data gathered during the field test were analyzed to characterize the sound propagation environment. Conventional geometric spreading assumptions were challenged for the sloping bathymetry characteristic of the Hawaiian coral reef environment. Geoacoustic parameters of the coral reef environment were extracted from transmission loss measurements using a nonlinear least-squares inversion. Losses were estimated for frequencies of 500 Hz, 2 kHz, 5 kHz, 10 kHz, and 15 kHz.Coral reefs are complicated and understudied acoustic propagation environments. In addition to geometric spreading, there are propagation losses due to bottom attenuation, volumetric scattering, and boundary scattering from bathymetric variability and sea surface roughness. On a Hawaiian coral reef, a field test was performed in shallow water during which low-level tones were projected from an underwater speaker and received by a single hydrophone at various ranges up to 500 m from the source. Acoustic data gathered during the field test were analyzed to characterize the sound propagation environment. Conventional geometric spreading assumptions were challenged for the sloping bathymetry characteristic of the Hawaiian coral reef environment. Geoacoustic parameters of the coral reef environment were extracted from transmission loss measurements using a nonlinear least-squares inversion. Losses were estimated for frequencies of 500 Hz, 2 kHz, 5 kHz, 10 kHz, and 15 kHz.

A detailed understanding of ecological soundscapes provides a window into ecosystem state that might otherwise go undetected. Rather than consider acoustic emissions of a particular species, a top down ecosystem acoustics point of view gives potentially valuable insights to reef ecosystem function. Simultaneous passive acoustic and video data were collected from coral reefs off the Kona Coast of Hawaii in January 2019 during a soundscape experiment. Frequent interactions between fish species as well as collective behaviors are identified and tracked by applying computer vision to video data. Comparison relating video data to acoustic data allows assessment of the same behaviors as simultaneously reflected in directional passive acoustic data. Collective consideration of acoustics and video offers insight into acoustic signatures of particular soniferous communities and behaviors amongst and between reef species. Machine learning applications match patterns between fish trajectories in videos and the sound field as received by a directional antenna. The relative level of biological activity and presence or absence of particular behaviors provides key data in the effort to understand coral reef ecosystem state.

The impulsive sounds produced by tropical fish are a prominent component of coral reef acoustic environments off Hawaii. The resultant ambient noise field is highly nonstationary, making it difficult to equalize the noise background when implementing standard intensity-based detectors on conventional hydrophones. Here we demonstrate how DIFAR sensors can be used to enhance the contrast between transient fish signals and background ambient noise, permitting simultaneous detection and triangulation of individual pulses. This approach assigns an azimuth to each time-frequency component of a conventional spectrogram, by computing the arctangent of the active intensity measured on two orthogonal axes. The resulting “azigram” can be processed using standard image processing methods to isolate connected regions that share the same azimuth, and to match similar regions on azigrams from nearby DIFAR sensors. The cross-matched bearings can then be used to triangulate the source. The technique is being used to study “hotspots” of fish activity on coral reef pinnacles.The impulsive sounds produced by tropical fish are a prominent component of coral reef acoustic environments off Hawaii. The resultant ambient noise field is highly nonstationary, making it difficult to equalize the noise background when implementing standard intensity-based detectors on conventional hydrophones. Here we demonstrate how DIFAR sensors can be used to enhance the contrast between transient fish signals and background ambient noise, permitting simultaneous detection and triangulation of individual pulses. This approach assigns an azimuth to each time-frequency component of a conventional spectrogram, by computing the arctangent of the active intensity measured on two orthogonal axes. The resulting “azigram” can be processed using standard image processing methods to isolate connected regions that share the same azimuth, and to match similar regions on azigrams from nearby DIFAR sensors. The cross-matched bearings can then be used to triangulate the source. The technique is being used to study...

The increasing detection of small testicular lesions by ultrasound (US) in adults can lead to unnecessary orchiectomies. This article describes their nature, reviews the available literature on this subject and illustrates some classical lesions. We also suggest recommendations to help characterization and management. The ESUR scrotal imaging subcommittee searched for original and review articles published before May 2015 using the Pubmed and Medline databases. Key words used were ‘testicular ultrasound’, ‘contrast-enhanced sonography’, ‘sonoelastography’, ‘magnetic resonance imaging’, ‘testis-sparing surgery’, ‘testis imaging’, ‘Leydig cell tumour’, ‘testicular cyst’. Consensus was obtained amongst the members of the subcommittee, urologist and medical oncologist. Simple cysts are frequent and benign, and do not require follow up or surgery. Incidentally discovered small solid testicular lesions detected are benign in up to 80 %, with Leydig cell tumours being the most frequent. However, the presence of microliths, macrocalcifications and hypoechoic areas surrounding the nodule are findings suggestive of malignant disease. Asymptomatic small testicular lesions found on ultrasound are mainly benign, but findings such as microliths or hypoechoic regions surrounding the nodules may indicate malignancy. Colour Doppler US remains the basic examination for characterization. The role of newer imaging modalities in characterization is evolving. • Characterization of testicular lesions is primarily based on US examination. • The role of MRI, sonoelastography, contrast-enhanced ultrasound is evolving. • Most small non-palpable testicular lesions seen on ultrasound are benign simple cysts. • Leydig cell tumours are the most frequent benign lesions. • Associated findings like microliths or hypoechoic regions may indicate malignancy.

Conventional and adaptive plane-wave beamforming with simultaneous recordings by large-aperture horizontal and vertical line arrays during the 2009 Philippine Sea Engineering Test (PhilSea09) reveal the rate of occurrence and the two-dimensional arrival structure of seismic phases that couple into the deep ocean. A ship-deployed, controlled acoustic source was used to evaluate performance of the horizontal array for a range of beamformer adaptiveness levels. Ninety T-phases from unique azimuths were recorded between Yeardays 107 to 119. T-phase azimuth and S-minus-P-phase time-of-arrival range estimates were validated using United States Geological Survey seismic monitoring network data. Analysis of phases from a seismic event that occurred on Yearday 112 near the east coast of Taiwan approximately 450 km from the arrays revealed a 22° clockwise evolution of T-phase azimuth over 90 s. Two hypotheses to explain such evolution-body wave excitation of multiple sources or in-water scattering-are presented based on T-phase origin sites at the intersection of azimuthal great circle paths and ridge/coastal bathymetry. Propagation timing between the source, scattering region, and array position suggests the mechanism behind the evolution involved scattering of the T-phase from the Ryukyu Ridge and a T-phase formation/scattering location estimation error of approximately 3.2 km.

Pooled data from 16 radiology centers were retrospectively analyzed to seek patients with pathologically proven testicular lymphoma and grayscale and color Doppler images available for review. Forty-three cases were found: 36 (84%) primary and 7 (16%) secondary testicular lymphoma. With unilateral primary lymphoma, involvement was unifocal (n = 10), multifocal (n = 11), or diffuse (n = 11). Synchronous bilateral involvement occurred in 6 patients. Color Doppler sonography showed normal testicular vessels within the tumor in 31 of 43 lymphomas (72%). Testicular lymphoma infiltrates through the tubules, preserving the normal vascular architecture of the testis. Depiction of normal testicular vessels crossing the lesion is a useful adjunctive diagnostic criterion.

The subcommittee on scrotal imaging, appointed by the board of the European Society of Urogenital Radiology (ESUR), have produced guidelines on imaging and follow-up in testicular microlithiasis (TML). The authors and a superintendent university librarian independently performed a computer-assisted literature search of medical databases: MEDLINE and EMBASE. A further parallel literature search was made for the genetic conditions Klinefelter’s syndrome and McCune-Albright syndrome. Proposed guidelines are: follow-up is not advised in patients with isolated TML in the absence of risk factors (see Key Points below); annual ultrasound (US) is advised for patients with risk factors, up to the age of 55; if TML is found with a testicular mass, urgent referral to a specialist centre is advised. Consensus opinion of the scrotal subcommittee of the ESUR is that the presence of TML alone in the absence of other risk factors is not an indication for regular scrotal US, further US screening or biopsy. US is recommended in the follow-up of patients at risk, where risk factors other than microlithiasis are present. Risk factors are discussed and the literature and recommended guidelines are presented in this article. • Follow up advised only in patients with TML and additional risk factors. • Annual US advised for patients with risk factors up to age 55. • If TML is found with testicular mass, urgent specialist referral advised. • Risk factors – personal/ family history of GCT, maldescent, orchidopexy, testicular atrophy.

Background The published literature suggests that malignant peripheral nerve sheath tumors (MPNST) occur at increased frequency in neurofibromatosis type 2 (NF2). A recent review based on incidence data in North America showed that 1 per 1000 cerebellopontine angle nerve sheath tumors were malignant. Objective To determine whether MPNST occurred spontaneously in NF2 by reviewing our NF2 database. Methods The prospective database consists of 1253 patients with NF2. One thousand and nine are known to be alive at last follow-up. The presence and laterality/pathology of vestibular schwannoma at diagnosis and last follow-up was sought. Results There were no cases of spontaneous MPNST with 2114 proven (n = 1150) and presumed benign (n = 964) vestibular schwannomas found. Two patients had developed MPNST (1 presumed) after having previously undergone stereotactic radiosurgery for a vestibular schwannoma. Conclusion In this series, and from the literature, malignant transformation of a vestibular schwannoma was not a feature of NF2 in the unirradiated patient. NF2 patients should not be told that they have an increased risk of malignant change in a vestibular schwannoma unless they undergo radiation treatment. However, very much larger datasets are required before it can be determined whether there is any association between NF2 and MPNST in the unirradiated patient.

OBJECTIVE: To describe the experience of auditory brainstem implantation (ABI) in patients with Neurofibromatosis type 2 (NF2).STUDY DESIGN: Retrospective case review.SETTING: Tertiary referral centre.PATIENTS: Implanted with a Cochlear ABI22 or ABI24M between 1994 and 2009 because of NF2 disease.INTERVENTION(S): Rehabilitative.MAIN OUTCOME MEASURE(S): Surgical complication rate; audiological outcomes.RESULTS: There were 50 primary ABI insertions in 49 patients, including 16 inserted at the time of first side tumor removal as a sleeper, and two revision repositionings which failed to improve outcome. Postoperatively three patients had cerebrospinal fluid leaks which did not require reoperation, one patient had meningitis, and eleven patients suffered either temporary or permanent lower cranial nerve dysfunction. Twenty-nine patients became full time users; a further 12 patients became non-users. Three patients died while their device was inactive. Five patients retain serviceable contralateral hearing. Audiological open set testing of users showed means of: environmental sounds discrimination 51%; phoneme discrimination: with ABI alone 22%/lip reading (LR) 45%/ABI with LR 65%; sentence testing: with ABI alone 13%/LR 19%/ABI with LR 54%.CONCLUSIONS: The majority of patients with NF2 implanted with an ABI find the device a useful aid to communication in conjunction with LR and in recognizing common environmental sounds. A small proportion gain open set discrimination. Almost a third of patients may end up as non-users. There is probably an increased risk of postoperative lower cranial nerve dysfunction so careful preoperative assessment is advised.