Multi-modal deep learning for joint prediction of otitis media and diagnostic difficulty.

Objectives: In this study, we propose a diagnostic model for automatic detection of otitis media based on combined input of otoscopy images and wideband tympanometry measurements. Methods: We present a neural network-based model for the joint prediction of otitis media and diagnostic difficulty. We use the subclassifications acute otitis media and otitis media with effusion. The proposed approach is based on deep metric learning, and we compare this with the performance of a standard multi-task network. Results: The proposed deep metric approach shows good performance on both tasks, and we show that the multi-modal input increases the performance for both classification and difficulty estimation compared to the models trained on the modalities separately. An accuracy of 86.5% is achieved for the classification task, and a Kendall rank correlation coefficient of 0.45 is achieved for difficulty estimation, corresponding to a correct ranking of 72.6% of the cases. Conclusion: This study demonstrates the strengths of a multi-modal diagnostic tool using both otoscopy images and wideband tympanometry measurements for the diagnosis of otitis media. Furthermore, we show that deep metric learning improves the performance of the models.

Comments on forward pressure and other reflectance-based quantities for delivering stimuli to the ear.

The forward pressure has been proposed as an "optimal" reflectance-based quantity for delivering stimuli to the ear during evoked otoacoustic-emission measurements and audiometry. It is motivated by and avoids detrimental stimulus-level errors near standing-wave antiresonance frequencies when levels are adjusted in situ. While enjoying widespread popularity within research, the forward pressure possesses certain undesirable properties, some of which complicate its implementation into commercial otoacoustic-emission instruments conforming to existing international standards. These properties include its inability to approximate the total sound pressure anywhere in the ear canal and its discrepancy from the sound pressure at the tympanic membrane, which depends directly on the reflectance. This paper summarizes and comments on such properties of the forward pressure. Further, based on previous published data, alternative reflectance-based quantities that do not share these properties are investigated. A complex integrated pressure, with magnitude identical to the previously proposed scalar integrated pressure, is suggested as a suitable quantity for avoiding standing-wave errors when delivering stimuli to the ear. This complex integrated pressure approximates the magnitude and phase of the sound pressure at the tympanic membrane and can immediately be implemented into standardized commercial instruments to take advantage of improved stimulus-level accuracy and reproducibility in the clinic.

Is a focus on 'recycling' useful? A wider look at metal mutability and the chemical character of copper alloys.

Recycling is increasingly visible in archaeological descriptions of technology. This has a range of benefits as we attempt to engage with the full complexity of the material past. However, this paper examines in more detail whether a singular focus on recycling is positive for archaeological science. It considers the historical relationship between recycling and the chemical analysis of early copper alloys, the constraints of the different conceptual and statistical techniques that can be employed, and broader ideas of metal mutability and the characterisation hypothesis. Overall, anything that widens our conceptual toolkit should be welcomed. However, it is most helpful to have recycling emerge from case study data as part of a broader approach, rather than to focus on it as a sole aim. Similarly, the prioritisation of provenance has sometimes not helped the field. Engaging with a wider 'characterisation hypothesis' would bring several benefits, and help build collaborations with other areas of archaeology.

A Deep Learning Approach for Detecting Otitis Media From Wideband Tympanometry Measurements.

OBJECTIVE: In this study, wepropose an automatic diagnostic algorithm for detecting otitis media based on wideband tympanometry measurements. METHODS: We develop a convolutional neural network for classification of otitis media based on the analysis of the wideband tympanogram. Saliency maps are computed to gain insight into the decision process of the convolutional neural network. Finally, we attempt to distinguish between otitis media with effusion and acute otitis media, a clinical subclassification important for the choice of treatment. RESULTS: The approach shows high performance on the overall otitis media detection with an accuracy of 92.6%. However, the approach is not able to distinguish between specific types of otitis media. CONCLUSION: Out approach can detect otitis media with high accuracy and the wideband tympanogram holds more diagnostic information than the commonly used techniques wideband absorbance measurements and simple tympanograms. SIGNIFICANCE: This study shows how advanced deep learning methods enable automatic diagnosis of otitis media based on wideband tympanometry measurements, which could become a valuable diagnostic tool.

Inter-rater reliability of the diagnosis of otitis media based on otoscopic images and wideband tympanometry measurements.

OBJECTIVES: This study aims to investigate the inter-rater reliability and agreement of the diagnosis of otitis media with effusion, acute otitis media, and no effusion cases based on an otoscopy image and in some cases an additional wideband tympanometry measurement of the patient. METHODS: 1409 cases were examined and diagnosed by an otolaryngologist in the clinic, and otoscopy examination and wideband tympanometry (WBT) measurement were conducted. Afterwards, four otolaryngologists (Ear, Nose, and Throat doctors, ENTs), who did not perform the acute examination of the patients, evaluated the otoscopy images and WBT measurements results for diagnosis (acute otitis media, otitis media with effusion, or no effusion). They also specified their diagnostic certainty for each case, and reported whether they used the image, wideband tympanometry, or both, for diagnosis. RESULTS: All four ENTs agreed on the diagnosis in 57% of the cases, with a pairwise agreement of 74%, and a Light's Kappa of 0.58. There are, however, large differences in agreement and certainty between the three diagnoses. Acute otitis media yields the highest agreement (77% between all four ENTs) and certainty (0.90), while no effusion shows much lower agreement and certainty (34% and 0.58, respectively). There is a positive correlation between certainty and agreement between the ENTs across all cases, and both certainty and agreement increase for cases where a WBT measurement is shown in addition to the otoscopy image. CONCLUSIONS: The inter-rater reliability between four ENTs was high when diagnosing acute otitis media and lower when diagnosing otitis media with effusion. However, WBT can add valuable information to get closer to the ground-truth diagnosis without myringotomy. Furthermore, the diagnostic certainty increases when the WBT is examined together with the otoscopy image.

Deep metric learning for otitis media classification.

In this study, we propose an automatic diagnostic algorithm for detecting otitis media based on otoscopy images of the tympanic membrane. A total of 1336 images were assessed by a medical specialist into three diagnostic groups: acute otitis media, otitis media with effusion, and no effusion. To provide proper treatment and care and limit the use of unnecessary antibiotics, it is crucial to correctly detect tympanic membrane abnormalities, and to distinguish between acute otitis media and otitis media with effusion. The proposed approach for this classification task is based on deep metric learning, and this study compares the performance of different distance-based metric loss functions. Contrastive loss, triplet loss and multi-class N-pair loss are employed, and compared with the performance of standard cross-entropy and class-weighted cross-entropy classification networks. Triplet loss achieves high precision on a highly imbalanced data set, and the deep metric methods provide useful insight into the decision making of a neural network. The results are comparable to the best clinical experts and paves the way for more accurate and operator-independent diagnosis of otitis media.

Social hierarchy and the choice of metal recycling at Anyang, the last capital of Bronze Age Shang China.

Anyang, the last capital of the Chinese Shang dynasty, became one of the largest metal consumers in Eurasia during the second millennium BCE. However, it remains unclear how Anyang people managed to sustain such a large supply of metal. By considering the chemical analysis of bronze objects within archaeological contexts, this paper shows that the casting and circulation of metal at Anyang was effectively governed by social hierarchy. Objects belonging to the high elites such as Fuhao, particularly the bronze ritual vessels, were made by carefully controlled alloying practice (primary) using very pure copper, whereas the lower elites only had access to bronzes made by secondary alloying practice and copper with more impurities. Such contrasts allow scholars to identify those objects which are less likely to have been made by mixing and recycling, which has very important implications for the chemical and isotopic determination of provenance for future studies.

Bereavement and transformation: a psycho-spiritual and post-traumatic growth perspective.

In the aftermath of loss, it is not uncommon for individuals to disclose psycho-spiritual experiences that lead to personal changes and psychological growth. This article argues for and outlines a broad conceptual framework that captures and acknowledges the significance of these subjective experiences. The model synthesises and integrates two approaches to healthy growth: Lawrence Calhoun and Richard Tedeschi's post-traumatic growth model and Stanislav and Christina Grof's model of psycho-spiritual transformation. A rationale for a broader model and underpinning theory is briefly discussed, and their shared understandings about the human potential for growth in the struggle through loss are explored.

Application of selected ion flow tube-mass spectrometry to the characterization of monofloral New Zealand honeys.

Honeys have a range of physicochemical and organoleptic properties, depending on the nectar source. Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS) is an emerging technology that quantifies volatile organic compounds (VOCs) to low concentrations (usually parts-per-trillion (ppt) levels) and is here applied to monitor the aromas in the headspace of different New Zealand monofloral honeys. Honey aromas arise from VOCs in the honeys that differ according to the flower type from which they were derived. In this exploratory study, the headspaces of nine monofloral New Zealand honeys (beech honeydew, clover, kamahi, manuka, rata, rewarewa, tawari, thyme, and vipers bugloss) were analyzed using SIFT-MS without sample preparation. The purpose of the investigation was to identify the major volatiles in each of the honeys and to test the feasibility of using SIFT-MS to distinguish between New Zealand monofloral honeys. In the nine monofloral honeys sampled, a clear distinction was observed between them based on their aroma signatures.

Burying shunts in bone cavities to protect delicate scalp.

The authors describe a simple technique for protecting at-risk scalp overlying CSF shunt hardware. Patients with brain tumors commonly undergo radiation therapy and CSF diversion. Chronic radiation-induced changes in the skin can predispose patients to skin breakdown over the prominent shunt reservoir, which may lead to subsequent contamination of the shunt hardware. The technique described reduces the risk of hardware contamination while obviating the need for revision of the entire shunt system. By reducing the profile of the CSF shunt reservoir, this technique also reduces the risk of future skin ulceration.

Active physician participation key to smooth MOE/MAR rollout.

Fundamental to the project's success was acceptance of MOE/MAR by UHN's physicians, yet many physicians questioned whether MOE/MAR would impede their ability to care for their patients. To ensure physician adoption, UHN presented MOE/MAR as a patient safety initiative from the beginning.

Bilateral vocal cord palsy during carotid endarterectomy under cervical plexus block.

We describe a case of vocal cord palsy leading to respiratory obstruction during carotid endarterectomy under cervical plexus block in a patient who had preexisting contralateral vocal cord paralysis subsequent to a previous thyroidectomy. The patient required immediate tracheal intubation and subsequent tracheostomy to maintain the airway postoperatively. Care must be given to avoid contralateral vocal cord paralysis in the presence of a preexisting vocal cord palsy.

Survival of microvascular physeal allograft transplants following withdrawal of short-term postoperative immunosuppression.

BACKGROUND: Physeal necrosis following vascularized allograft transplantation occurs because of vascular rejection. The effect of immunosuppression withdrawal on physeal viability after bone-healing to the recipient site was investigated with use of a validated model for heterotopic microvascular transplantation of rabbit tibial physeal allografts. Our hypothesis was that an allograft survives after withdrawal of immunosuppression only if bone-healing, and therefore epiphyseal and metaphyseal vascular continuity, occurs between the transplanted physis and the recipient bone. METHODS: Physeal grafts with adjacent exposed epiphyseal and metaphyseal bone were transplanted to allogeneic recipients. Graft circulation was restored microsurgically. The immunosuppression regimen consisted of cyclosporine, administered for six weeks, followed by withdrawal of immunosuppression for four weeks. The animals were killed at ten weeks postoperatively. Group I consisted of twelve allografts that were transferred with bone contact between the transplanted graft and the iliac crest recipient site, whereas group II consisted of twelve allografts transplanted without bone contact. Control groups had identical surgical procedures without immunosuppression. Longitudinal growth was assessed by fine-detail radiography, and osseous union was evaluated histologically. Transplanted physes were evaluated histologically, and cellular viability was quantified by bromodeoxyuridine uptake. Two-way analysis of variance was used to compare physeal viability between groups. RESULTS: Following immunosuppression withdrawal, the physeal grafts with bone contact had significantly greater viability indices (16.0 +/- 2.9 compared with 0.0 +/- 0.0, p < 0.005) and decreased longitudinal growth (5.1 +/- 1.9 mm compared with 10.3 +/- 3.5 mm, p < 0.05), and they demonstrated histological features that were consistent with continued viability associated with mild rejection compared with grafts transplanted without bone contact. Abnormalities of physeal architecture, however, were seen routinely. All control physes transferred without immunosuppression were nonviable and did not grow. CONCLUSIONS: The viability of physeal allograft transplants is preserved following the withdrawal of immunosuppression, provided that the graft design and recipient site preparation allow for epiphyseal and metaphyseal neovascularization mediated by bone-healing between graft and recipient.

Scalp ulceration from a circumferential head dressing after craniotomy: Case report of an uncommon complication due to human error.

The present paper describes a previously unpublished complication of the application of a circumferential head dressing after cranial neuro-surgery. A 34-year-old woman developed a large area of skin necrosis on her forehead from a circumferential head dressing applied after the surgical removal of a colloid cyst. Neurological recovery was excellent but plastic surgical repair of her iatrogenic cosmetic injury was required.

Le présent article décrit une complication jamais publiée auparavant, secondaire à l'application d'un pansement circonférentiel de la tête après une neurochirurgie crânienne. Une femme de 34 ans a développé une grande zone de nécrose cutanée sur le front après l'application d'un pansement circonférentiel de la tête suivant l'excision chirurgicale d'un kyste colloïde. Le rétablissement neurologique a été excellent, mais il a fallu procéder à une réparation par chirurgie plastique de la blessure iatrogène cosmétique.

Percutaneous treatment of long superficial femoral artery occlusive disease: efficacy of the Hemobahn stent-graft.

PURPOSE: To assess the efficacy of the Hemobahn stent-graft in the percutaneous treatment of long occlusive lesions of the superficial femoral artery (SFA). METHODS: Fifty-nine limbs in 54 patients (42 men; mean age 73.3+/-8.2 years, range 55.2-91.3) with 59 symptomatic SFA occlusions >10 cm in length were selected for percutaneous treatment with the Hemobahn stent-graft. The treated SFA was assessed for patency and degree of stenosis by color-flow duplex ultrasound prior to discharge and at 1, 3, and 6 months and yearly thereafter. The actuarial life-table method was used to derive primary and secondary patency rates. RESULTS: Primary technical success was achieved in 56 (95%) of 59 limbs on an intention-to-treat basis (2 access and 1 device failures). In the first 30 days, 4 (6.8%) stent-graft thromboses and 5 (8.5%) minor technical difficulties occurred. Up to 1 year, there were 15 (25.4%) primary occlusions, 7 (11.9%) of which were associated with restenosis. Cumulative primary patencies were 88%, 67%, and 58% at 1, 6, and 12 months, respectively; secondary patencies were 92%, 82%, and 73% at the same intervals. There was no statistically significant difference (p<0.05) in patency (primary or secondary) with respect to presenting symptoms, lesion length, stent-graft length, or distal runoff. CONCLUSIONS: Symptomatic long occlusive lesions of the SFA treated percutaneously with the Hemobahn stent-graft achieved good outcomes initially with a low complication rate. Primary and secondary patencies were similar to those reported for open synthetic femoropopliteal bypass procedures.

Iatrogenic vertebral arteriovenous fistula treated with a hemobahn stent-graft.

PURPOSE: To illustrate the utility of color flow duplex ultrasound (CFDU) in the diagnosis and stent-graft treatment of a rare arteriovenous fistula (AVF) involving the vertebral artery and vein. CASE REPORT: An iatrogenic AVF involving the right vertebral artery and vein was diagnosed in a 45-year-old man using CFDU. Treatment was recommended due to the large volume of blood shunted through the fistula and the associated loud bruit. Endoluminal treatment involved deployment of a covered stent within the vertebral artery to exclude the fistula. Postoperative CFDU confirmed the success of the treatment. CONCLUSIONS: CFDU can be utilized to accurately diagnose unusual lesions, such as AVFs involving the vertebral artery. The technique is also useful in planning treatment and monitoring the durability of stent-grafts implanted to obliterate this type of defect.