Fluorescence Multi-Detection Device Using a Lensless Matrix Addressable microLED Array.

A Point-of-Care system for molecular diagnosis (PoC-MD) is described, combining GaN and CMOS chips. The device is a micro-system for fluorescence measurements, capable of analyzing both intensity and lifetime. It consists of a hybrid micro-structure based on a 32 × 32 matrix addressable GaN microLED array, with square LEDs of 50 µm edge length and 100 µm pitch, with an underneath wire bonded custom chip integrating their drivers and placed face-to-face to an array of 16 × 16 single-photon avalanche diodes (SPADs) CMOS. This approach replaces instrumentation based on lasers, bulky optical components, and discrete electronics with a full hybrid micro-system, enabling measurements on 32 × 32 spots. The reported system is suitable for long lifetime (>10 ns) fluorophores with a limit of detection ~1/4 µM. Proof-of-concept measurements of streptavidin conjugate Qdot™ 605 and Amino PEG Qdot™ 705 are demonstrated, along with the device ability to detect both fluorophores in the same measurement.

Design study of a micro illumination platform based on GaN microLED arrays.

The design study of a micro illumination tool based on GaN microLED arrays is presented. The high spatio-temporal resolution and the capability of generating fully customized optical patterns that characterize the proposed platform would enable the manipulation of biological systems, e.g., for optogenetics applications. Based on ray tracing simulations, the design aspects that mainly affect the device performance have been identified, and the related structural parameters have been optimized to improve the extraction efficiency and the spatial resolution of the resulting light patterns. Assuming that the device is a bottom emitter, and the light is extracted from the n-side, the presence of mesa-structures on the p-side of the GaN layer can affect both the efficiency and the resolution, being optimized for different values of the mesa-side inclination angle. The full width at half maximum (FWHM) of the extracted spots is mainly determined by the substrate thickness, and the relation between the FWHM and the array pitch represents a criterion to define the resolution. Namely, when F W H M

Positive predictive values of ultrasound-guided fine-needle aspiration with parathyroid hormone assay and Tc-99m sestamibi scintigraphy in sporadic primary hyperparathyroidism.

OBJECTIVES: Ultrasonography (US) and Tc-99m sestamibi scintigraphy (SS) are usually performed as preoperative imaging modalities for patients with sporadic primary hyperparathyroidism (SPHP). Fine-needle aspiration (FNA) under US guidance for parathyroid hormone (PH) assay can enhance the diagnostic accuracy of US. The main aim of the present study was to compare positive predictive values between US-FNA and SS. The secondary aim was to draw up a decision-tree for FNA and SS. METHODS: The single-center retrospective study included patients with previously non-operated SPHP. They underwent US-guided FNA, PET-CT SS, and 18 F-choline scintigraphy if the first two methods were inconclusive. PH washout level was considered pathological when greater than the serum PH level. Postoperative histology data were correlated to imaging data. RESULTS: In total, 117 patients were included, with a mean age of 64 years (range, 26-89 years). A single adenoma was identified on pathology in 101 patients (89%). FNA findings were pathologic for 64 patients (55%), with a mean PH level of 2,604ng/L [range, 585-9,074ng/L], higher than the serum level of 179ng/L [range, 60-1,000ng/L]. US-guided FNA showed sensitivity, specificity, and positive and negative predictive values (PPV, NPV) of respectively 72%, 92%, 99% and 28%, compared to 89%, 42%, 93% and 32% for SS. The rate of error in locating the parathyroid gland was 8% for US-guided FNA versus 12% for SS. Comparison of the two methods showed better sensitivity for SS (P=0.0052) and better specificity for FNA (P=0.0143), with no significant difference in PPV or NPV. 18 F-choline scintigraphy detected the hyperfunctioning parathyroid in 11 out of the 15 patients. CONCLUSION: PPV did not significantly differ between FNA and SS. US-guided FNA performed by an experienced operator could be a simple first-line method for more than 50% of patients with non-operated SPHP, with 99% PPV. In case of negative or doubtful FNA findings, SS can be performed in second line.

Endonasal endoscopic approach to the pterygopalatine and infratemporal fossae.

The pterygopalatine fossa and infratemporal fossa are spaces located under the skull base, housing important neurovascular structures. Surgical access to these spaces is challenging because of their deep location and complex anatomy. Their surgical access has been classically carried out through multiple craniofacial approaches until the advent of endoscopic endonasal surgery at the end of the XXth century. Our goal is to describe the transmaxillary-transsphenoidal-transpterygoid approach to the pterygopalatine and infratemporal fossae through endonasal endoscopic surgery based on anatomo-surgical dissection and an illustrative clinical case. We conclude that after careful radiologic evaluation of the feasibility of this technique, the endonasal endoscopic access to these spaces for tumor resection is efficient with reduced surgical morbidities. The endonasal approach is versatile and can be fashioned according to the nature and extent of the lesion.

Plasmon expedited response time and enhanced response in gold nanoparticles-decorated zinc oxide nanowire-based nitrogen dioxide gas sensor at room temperature.

A highly sensitive and rapidly responsive nitrogen dioxide (NO2) gas sensor based on gold (Au) nanoparticles (NPs)-decorated zinc oxide (ZnO) nanowires (NWs) is presented. The Au NPs decoration was conducted onto ZnO NWs with and without a (3-aminopropyl)triethoxysilane (APTES) layer on their surface by using the electrostatic force. The samples without the APTES layer exhibited high NO2 gas sensitivity (i.e. expedited response time and enhanced gas response) due to localized surface plasmon resonance (LSPR) of the Au NPs; in particular, the NO2 gas response and the response time were increased by three times and shortened by 86%, respectively, compared with the undecorated ZnO NWs. The presence of the APTES layer improved the Au NPs attachment, but hindering the gas adsorption on the ZnO NWs surface, as proven by the observed photocurrent and gas response. Our findings imply that the response time of semiconductor gas sensors can be remarkably expedited by the LSPR effect, which is useful for developing practical gas sensors.

Optical design of InGaN/GaN nanoLED arrays on a chip: toward: highly resolved illumination.

The physical laws of diffraction limit the spatial resolution of optical systems. In contrary to most superresolution microscopy approaches used today, in our novel idea we are aiming to overcome this limit by developing a spatially resolved illumination source based on semiconductor nanoscale light emitting diode (nanoLED) arrays with individual pixel control. We present and discuss the results of optical simulations performed for such nanoLED emitter arrays and analyze the theoretical limits of this approach. As possible designs we study arrays of GaN nanofins and nanorods (obtained by etching nanofin arrays), with InGaN/GaN multi quantum wells embedded as active regions. We find that a suitable choice of the array dimensions leads to a reasonably directed light output and concentration of the optical power in the near field around an activated pixel. As a consequence, the spatial resolution for this type of microscopy should only be limited by the pixel pitch, and no longer by the optical diffraction. Realization of optimized nanoLED arrays has a potential to open new field of chip based superresolution microscopy, making super-high spatial resolution ubiquitously available.

Thyroid surgery under hypnosis: A 50-case series.

OBJECTIVES: The study objective was to compare patient satisfaction after thyroid lobo-isthmectomy under hypnoanesthesia versus general anesthesia. METHODS: A retrospective study included 100 patients undergoing lobo-isthmectomy. A group of 50 patients under hypnoanesthesia was compared to a control group of 50 patients under general anesthesia. Satisfaction was assessed on questionnaire between three and six months after surgery. We also compared secondary criteria: procedure time, blood loss, intraoperative comfort, postoperative pain, postoperative complications and time to resumption of daily activities. RESULTS: Our study showed good overall satisfaction in patients operated under hypnoanesthesia, for equivalent operative safety and complications rate compared to general anesthesia. For comparable analgesia, postoperative pain was lower, but not significantly, in the Hypnosis group, while the rate of nausea and vomiting was significantly lower (p<0.05). Postoperative convalescence was shorter in the Hypnosis group: 3.7 versus 9.2 days (p<0.001). CONCLUSION: In thyroid surgery, hypnoanesthesia has real advantages over general anesthesia in that it places the patient at the center of the care team's attention. His or her active participation is essential during the process, bringing a new dimension to care, beneficial for the patient. However, it must be reserved for minimally invasive procedures in which organization is anticipated in full collaboration within teams that are willing and experienced.

Intraoperative neuromonitoring by vagus nerve stimulation in thyroid surgery: Clinical assessment of recurrent and superior laryngeal nerves.

Intraoperative neuromonitoring of the laryngeal nerves during thyroidectomy is a reliable method to assess nerve function. After identification of the cricothyroid ligament, a bipolar electrode is selectively inserted through the ligament into the thyroarytenoid muscle (TAM) and cricothyroid muscle (CTM). Vagus nerve stimulation then allows precise monitoring of the recurrent laryngeal nerve and the external branch of the superior laryngeal nerve (EBSLN) in the TAM and CTM, respectively. A significant muscle response (greater than 100µV) is 100% predictive of preserved laryngeal mobility, while the absence of a muscle response is 70% predictive of vocal fold paralysis with 100% sensitivity and 98% specificity. A significant thyroarytenoid muscle response is only recorded ipsilateral to the stimulation with a shorter latency on the right side. A concomitant TAM and CTM response to vagus nerve stimulation or EBSLN stimulation is observed in more than 70% of cases.

Adjuvant management of operated uterine sarcomas: A single institution experience.

PURPOSE: The purpose of this study was to describe the adjuvant management of high grade uterine sarcoma and highlight prognostic factors for overall survival and progression-free survival. MATERIAL AND METHODS: Between 01/2000 and 01/2015, 91 patients undergoing surgery were presented at the multidisciplinary team meeting of our institution. The type of surgery, the anatomopathological features, adjuvant treatments, dates and sites of recurrence were collected. The prognostic value of the various factors was evaluated with the multivariate Cox model. RESULTS: A total of 50 women with uterine sarcoma were identified and lesions included 43 leiomyosarcomas (86%) and seven high grade sarcomas (14%). Eighteen patients received adjuvant pelvic radiotherapy (36%) and six adjuvant systemic therapy (12%). The median follow-up time was 63 months. Thirty-nine patients (78%) had a recurrence: 22 had only metastatic recurrence (58%), two had isolated pelvic recurrence (5%) and 15 had pelvic and metastatic recurrence (38%). Adjuvant radiotherapy was associated with survival without pelvic recurrence in univariate analysis (P=0.005, hazard ratio [HR]=0.15); age greater than 55 years and adjuvant radiotherapy were associated with metastatic free survival in multivariate analysis (P=0.015, HR=2.37, and P=0.013, HR=0.41 respectively) CONCLUSION: According to the results of our series, there is a benefit of radiotherapy after surgery in terms of local control of uterine sarcoma. It is necessary to identify the subgroup of patients who will benefit from an adjuvant radiotherapy in order to provide them with more optimal care.

Sensitivity-Selectivity Trade-Offs in Surface Ionization Gas Detection.

Surface ionization (SI) provides a simple, sensitive, and selective method for the detection of high-proton affinity substances, such as organic decay products, medical and illicit drugs as well as a range of other hazardous materials. Tests on different kinds of SI sensors showed that the sensitivity and selectivity of such devices is not only dependent on the stoichiometry and nanomorphology of the emitter materials, but also on the shape of the electrode configurations that are used to read out the SI signals. Whereas, in parallel-plate capacitor devices, different kinds of emitter materials exhibit a high level of amine-selectivity, MEMS (micro-electro-mechanical-systems) and NEMS (nanowire) versions of SI sensors employing the same kinds of emitter materials provide significantly higher sensitivity, however, at the expense of a reduced chemical selectivity. In this paper, it is argued that such sensitivity-selectivity trade-offs arise from unselective physical ionization phenomena that occur in the high-field regions immediately adjacent to the surfaces of sharply curved MEMS (NEMS) emitter and collector electrodes.

Anatomical and histological study of the deep neck fasciae: does the alar fascia exist?

PURPOSE: The aim of this study was to determine whether the alar fascia is a distinct layer of the deep cervical neck fasciae. The present study also aimed to elucidate the anatomical limits of this fascia. METHODS: Neck dissections of ten adult cadavers were performed, layer by layer, in the retropharyngeal region, under a powered operating microscope. Detailed dissections revealed the anatomical limits of the deep neck fasciae. Histological descriptions were also performed on large tissue samples collected from three cervical dissections. RESULTS: In the ten dissections, three layers of fascia were identified and dissected in the retropharyngeal region: a visceral fascia, a prevertebral fascia and an alar fascia. The alar fascia appeared like a connecting band derivative of the visceral fascia, between both vascular sheaths. It fused completely with the visceral fascia anteriorly at the level of T2 and with the prevertebral fascia posteriorly at the level of C1. No sagittal connection between the visceral fascia and the prevertebral fascia was identified. The stained histological sections confirmed the presence of the visceral and prevertebral fasciae at the oropharyngeal level, with a third intermediate layer closely connected with the visceral fascia. CONCLUSION: The alar fascia is a layer of the cervical neck fascia connected with the visceral fascia from C1 to T2 levels. The anatomical limits of this alar fascia and its relationships with the internal carotid artery are important in the surgical management and the prognosis of deep neck infections and retropharyngeal lymph node metastases.

Superior laryngeal nerve in thyroid surgery: anatomical identification and monitoring.

The aim of this study was to validate a procedure to identify and preserve the external branch of the superior laryngeal nerve (EBSLN) during thyroid surgery. The present study also aimed to analyze the EBSLN and the vagus nerve activities after stimulation and demonstrate an operative association between all the laryngeal muscles. Dissection of the cervical region was performed bilaterally in four adult cadavers. In a second step, 144 patients undergoing total thyroidectomy were included. Intraoperative stimulations of the cervical vagus nerve and the EBSLN in the sternothyroid-laryngeal triangle were performed bilaterally. Potentials in the thyroarytenoid muscle and the cricothyroid muscle were registered on each side using the NIM3 Medtronic System. EBSLN was identified according to Cernea's classification as type 1 in 62.5%, type 2a in 25%, and type 2b in 12.5% of cadaver's dissection. According to Friedman's classification, 50% of EBSLN were classified type 1, 25% type 2 and 25% type 3. The EBSLN was identified in 267 cases out of 288 peroperative dissections (92.7%). Direct stimulation (1 mA) of this branch led to a recordable contraction of the cricothyroid muscle with a mean latency of 1.42 ± 0.66 ms on the right side and 1.43 ± 0.61 ms on the left side. The stimulation of the EBSLN also led to a recordable contraction of the thyroarytenoid muscle in 211 cases (73.3%) with the same latencies. A contraction of the cricothyroid muscle was also recorded when the vagus nerve was stimulated in 219 cases (76.0%). The sole visual identification of the EBSLN during thyroid surgery is not a reliable method to prevent nerve injury. Direct stimulation of the EBSLN in the sternothyroid-laryngeal triangle is a simple and rapid procedure to detect and preserve the nerve during surgery. Functional associations between vagus nerve and EBSLN in laryngeal muscles' contractions were also identified.

Tubotympanic system functioning.

The Eustachian (auditory) tube and tympanomastoid cavities form an anatomic and functional whole that cannot easily be divided, and is therefore known as the "tubotympanic system". The system has been the focus of several studies, with complex and sometimes contradictory results, making an overview of its functioning difficult to obtain. The objective of the present article is to review the current state of knowledge, as an indispensable preliminary to understanding tubotympanic system dysfunction, and notably the development of chronic otitis. The system as a whole is covered by mucosa, which provides continuity, although with certain particularities from one area to another, and plays a primordial role. Thus, under physiological conditions, gas diffusion across the tympanomastoid mucosa largely ensures the equilibrium of pressure between the middle ear and outside environment, the tube orifice being very little involved. Under large rapid change in atmospheric pressure, the aeration function of the Eustachian tube comes into play, governed by a reflex mechanism. The system also has other functions that are essential to good middle-ear functioning: protection against nasopharyngeal secretions and pathogens and against certain physiological noises; middle-ear cavity clearance by mucociliary transport of pathogens, partly related to submucosal gland secretion; and immune defense.

[The parapharyngeal adipose corpus: Surgical anatomy and imaging]. / Le corps adipeux parapharyngé : anatomie chirurgicale et imagerie.

The aim of this study is to define the parapharyngeal adiposis corpus (PAC) and its anatomical relationships originally described by P. Sebileau in 1892 to assess the potential clinical implications. MATERIALS AND METHODS: Seven frozen fresh cadavers were used, 3 of which after injection of latex neoprene colored in cervicocephalic arterial network. A MRI was performed in 10 patients without cervical pathology. The analysis was done on the frontal and transverse T1-weighted sections. RESULTS: The PAC, which is a yellowish fat formation, fills the paratonsillar space. It measures an average of 4.8cm (4.5 to 5.2cm) in length and 1.2cm (1.1 to 1.5cm) for subjects of varying size and sex. Its arterial supply is mainly provided by the ascending palatine artery, an early branch of the facial artery. A left-right symmetry was found on MRI analyses regardless of sex or age. It is found in all the medial and ventral cases on the pharyngeal extension of the parotid gland in homogeneous hyperintense T1. CONCLUSION: The PAC is a constant fat structure. Its vascularization depends mainly on the ascending palatine artery. Through its association with fatty peripharyngeal space, it could be a functionally sliding space. In imaging, it may be helpful in the interpretation of images of the pharyngeal extension of the parotid gland tumors.

Real-life efficacy of volumetric modulated arc therapy in head and neck squamous cell carcinoma.

OBJECTIVES: There is paucity of data on the efficacy of volumetric modulated arc therapy (VMAT) in head and neck squamous cell carcinoma (HNSCC). The objective of the present study was to investigate outcomes and patterns of recurrence in locally advanced HNSCC treated by VMAT. METHODS: A retrospective study included all patients with stage III or IV HNSCC undergoing curative VMAT. RESULTS: From 2010 to 2013, 130 patients were treated for locally advanced oropharynx (n=55; 42%), hypopharynx (n=38; 29%), larynx (n=22; 17%) or oral cavity (n=15; 12%) SCC. Median age was 60 years (range, 39-85). Median follow-up was 18.1 months (range, 0-43.7). By end of follow-up, 60 patients (46%) had died. Two-year progression-free and overall survival were respectively 63.6% and 77.3% for laryngeal tumors, 60% and 60% for oral cavity tumors, 52.6% and 57.6% for oropharyngeal tumors, and 38.8% and 54.7% for hypopharyngeal tumors. Most recurrences were located within or marginal to radiation therapy fields. CONCLUSION: This retrospective analysis is, to our knowledge, the largest study of the efficacy of VMAT in HNSCC. Recurrence patterns and outcomes were consistent with those previously reported for intensity-modulated radiotherapy.

Improving survival and local control in rectal cancer in Catalonia (Spain) in the context of centralisation: A full cycle audit assessment.

BACKGROUND: Rectal cancer surgery in Catalonia has been involved in a process of centralisation. We assessed the impact of this health policy strategy on quality of care and clinical results. METHODS: We compared patterns of care and clinical outcomes of all rectal cancer patients receiving radical surgery for the first time in public hospitals in two time periods, before (2005 and 2007) and after (2011-2012) centralisation, analysing indicators of care quality according to the regional clinical practice guidelines. Clinical outcomes at two years were also assessed. RESULTS: A total of 3780 patients were included. From 2005 to 2012, the proportion of patients treated surgically for the first time in centres whose annual surgical caseload was more than 11 increased from 84.0% to 90.4%. The rate of locoregional recurrence at two years fell from 4.5 to 3.06/100 person-years (p = 0.005). The crude mortality rate at three months, one and two years was reduced by 55%, 40% and 34% (p < 0.001). CONCLUSION: Improvements in quality of care might be associated with the centralisation of surgery and with the selective focus effect derived from the process of auditing. Our results support the continuation of clinical auditing and surveillance of authorised centres.

Infracentimetric cervical lymph node metastasis in head and neck squamous cell carcinoma: Incidence and prognostic value.

OBJECTIVES: Supracentimetric cervical lymph node metastasis is classically a poor prognostic factor for locoregional recurrence and survival in head and neck cancer. Causality, however, is more controversial for infracentimetric cervical lymph node metastases. The objective of this study was to evaluate the incidence and prognostic value of infracentimetric lymph node metastasis. MATERIALS AND METHODS: Two hundred and forty-three neck dissections from 150 head and neck cancer patients were analyzed. A single pathologist exhaustively inventoried the number and size of all adenopathies in the surgical specimen. RESULTS: Cervical lymph node metastases were infracentimetric in 38% of cases, with 72% extracapsular spread (versus 91% for supracentimetric adenopathies; P<0.01). Infracentimetric metastases were more often associated with other cervical lymph node metastases (mean 5.3 versus 3.9; P=0.14). Fifty three percent of specimens showed only supracentimetric metastases (versus 13% infracentimetric metastases; P<0.01). Disease-specific and failure-free survival were lower in case of infracentimetric metastasis, associated with supracentimetric metastasis or not, than in case of macrometastasis only. CONCLUSION: Infracentimetric cervical lymph node metastasis is a factor of poor prognosis, and may represent a different, more aggressive lymphatic process. We suggest complete neck dissection by the surgeon and meticulous analysis by the pathologist, the results of which guide complementary therapy. Close surveillance of recurrence is also recommended.