Cascades of Parametric Instabilities in the Tokamak Plasma Edge during Electron Cyclotron Resonance Heating.

We report observations of nonlinear two-plasmon decay instabilities (TPDIs) of a high-power microwave beam, a process similar to half-harmonic generation in optics, during electron cyclotron resonance heating in a tokamak. TPDIs are found to occur regularly in the plasma edge due to wave trapping in density fluctuations for various confinement modes, and the frequencies of both observed daughter waves agree with modeling. Emissions from a cascade of subsequent decays, which indicate a generation of ion Bernstein waves, are correlated with fast-ion generation. This emphasizes the limitations of standard linear microwave propagation models and possibly paves the way for novel microwave applications in plasmas.

Development of the 174 GHz collective Thomson scattering diagnostics at Wendelstein 7-X.

In this paper, we present the design and commissioning results of the upgraded collective Thomson scattering diagnostic at the Wendelstein 7-X stellarator. The diagnostic has a new radiometer designed to operate between the second and third harmonics of the electron cyclotron emission from the plasma at 171-177 GHz, where the emission background has a minimum and is of order 10-100 eV. It allows us to receive the scattered electromagnetic field with a significantly improved signal-to-noise ratio and extends the set of possible scattering geometries compared to the case of the original instrument operated at 140 GHz. The elements of the diagnostic are a narrowband notch filter and a frequency stabilized probing gyrotron that will allow measuring scattered radiation spectra very close to the probing frequency. Here, we characterize the microwave components applied to the radiometer and demonstrate the performance of the complete system that was achieved during the latest experimental campaign, OP2.1.

The upgraded TOMAS device: A toroidal plasma facility for wall conditioning, plasma production, and plasma-surface interaction studies.

The Toroidal Magnetized System device has been significantly upgraded to enable development of various wall conditioning techniques, including methods based on ion and electron cyclotron (IC/EC) range of frequency plasmas, and to complement plasma-wall interaction research in tokamaks and stellarators. The toroidal magnetic field generated by 16 coils can reach its maximum of 125 mT on the toroidal axis. The EC system is operated at 2.45 GHz with up to 6 kW forward power. The IC system can couple up to 6 kW in the frequency range of 10 MHz-50 MHz. The direct current glow discharge system is based on a graphite anode with a maximum voltage of 1.5 kV and a current of 6 A. A load-lock system with a vertical manipulator allows exposure of material samples. A number of diagnostics have been installed: single- and triple-pin Langmuir probes for radial plasma profiles, a time-of-flight neutral particle analyzer capable of detecting neutrals in the energy range of 10 eV-1000 eV, and a quadrupole mass spectrometer and video systems for plasma imaging. The majority of systems and diagnostics are controlled by the Siemens SIMATIC S7 system, which also provides safety interlocks.

Dysphagia in neurological diseases: a literature review.

Dysphagia is defined as an impairment of this complex and integrated sensorimotor system. It is estimated that 400,000 to 800,000 individuals worldwide develop neurogenic dysphagia per year. Neurogenic dysphagia is typically occurring in patients with neurological disease of different etiologies. A correct and early diagnosis and an appropriate management of dysphagia could be useful for improving patient's quality of life and may help to prevent or delay death. In the present review, we discuss thoroughly the anatomy and physiology of swallowing and also the pathophysiological mechanisms involved in impaired swallowing, as well as the diagnosis, management, and potential treatments of neurogenic dysphagia. Assessment of neurogenic dysphagia includes medical history, physical exam, and instrumental examinations (fiberoptic endoscopic evaluation of swallowing, videofluoroscopic swallowing study, electromyography). Pharmacological treatment of these problems includes oral anticholinergic drugs. Surgical myotomy of the cricopharyngeal muscle showed an important improvement of oropharyngeal dysphagia associated to upper esophageal sphincter hyperactivity. Chemical myotomy of the upper esophageal sphincter by local injections of botulinum toxin type A into the cricopharyngeal muscle has been proposed as an alternative less invasive and less unsafe than surgical myotomy.

The role of peak nasal and oral inspiratory flow in the evaluation of patients with sleep-related breathing disorders.

BACKGROUND: Sleep-related breathing disorders (SRBD) are common reported disorders in the adult population. The nose plays an important role in the development of SRBD; thus, the measurement of nasal respiratory function remains an important step in the management of these patients. Peak nasal inspiratory flow (PNIF) is a useful tool to assess nasal airflow and it has recently been studied together with peak oral inspiratory flow (POIF). OBJECTIVE: The aim of the present study was to evaluate the role of PNIF and POIF in an adult population of patients affected by SRBD. METHODOLOGY: Seventy consecutive adult patients with SRBD were included in the present study. All patients were evaluated with home-based sleep studies (type III), PNIF, POIF, SNOT-22 questionnaire, Epworth Sleepiness Scale test and VAS for nasal obstruction. RESULTS: Although PNIF and POIF showed to correlate with each other, no correlations were observed between Apnea Hypopnea index (AHI) and PNIF, POIF or NPI (PNIF/POIF). A further analysis showed a marginal correlation between SNOT- 22 and AHI and between SNOT-22 and POIF. Furthermore, in a multivariate analysis, also POIF marginally correlated with some of the sleep- related SNOT-22 items. CONCLUSIONS: In the present study neither PNIF nor POIF were found to be associated with OSAS severity. However, POIF values correlated better than PNIF with sleep related symptoms suggesting that POIF could be a more useful parameter for upper airway assessment in patients with SRBD. In addition, a correlation between OSAS severity, in terms of AHI, and SNOT-22 total score has been reported.

Olfactory and rhinological evaluations in SARS-CoV-2 patients complaining of olfactory loss.

Since December 2019, a novel coronavirus SARS-CoV-2 (Covid-19) outbreak emerged in China and spread rapidly in several countries. As of April 5, 2020, 1.218.474 cases were confirmed with 65.884 deaths worldwide (1). The clinical manifestations of Covid-19 range from asymptomatic carrier status to severe pneumonia. In a study of 7,736 Covid-19 patients in China, of all the clinical symptoms, hyposmia was not reported in any patient(2). Anyway, it is now clear that olfactory dysfunction may also be present in these patients(3) as the only or prevalent manifestation(4).

Botulinum toxin therapy: functional silencing of salivary disorders.

Botulinum toxin (BTX) is a neurotoxic protein produced by Clostridium botulinum, an anaerobic bacterium. BTX therapy is a safe and effective treatment when used for functional silencing of the salivary glands in disorders such as sialoceles and salivary fistulae that may have a post-traumatic or post-operative origin. BTX injections can be considered in sialoceles and salivary fistulae after the failure of or together with conservative treatments (e.g. antibiotics, pressure dressings, or serial aspirations). BTX treatment has a promising role in chronic sialadenitis. BTX therapy is highly successful in the treatment of gustatory sweating (Frey's syndrome), and could be considered the gold standard treatment for this neurological disorder.

Dosimetric predictors of acute hematologic toxicity during concurrent intensity-modulated radiotherapy and chemotherapy for anal cancer

Purpose. This study aimed at investigating whether the irradiated volume of pelvic bone marrow (PBM) and specific subsites may predict the occurrence of acute hematologic toxicity (HT) in anal cancer patients undergoing concurrent chemo-radiation. Methods. 50 patients, submitted to IMRT and concurrent chemotherapy, were analyzed. Several bony structures were defined on planning-CT: PBM and lumbar-sacral (LSBM), lower pelvis (LPBM) and iliac (IBM) bone marrow. On dose-volume histograms, dosimetric parameters were taken. Endpoints included white blood-cell-count (WBC), absolute-neutrophil-count (ANC), hemoglobin (Hb) and platelet nadirs and acute hematologic toxicity (HT) according to RTOG scoring scale. Generalized linear modeling was used to find correlations between dosimetric variables and blood cell nadirs, while logistic regression analysis was used to test correlation with ≥G3 HT. Receiver Operating Characteristic (ROC) curve analysis was used to evaluate the optimal cut-off points for predictive dosimetric variables with the Youden method. Results. Maximum detected acute HT comprised 38 % of ≥G3 leukopenia and 32 % of ≥G3 neutropenia. Grade 2 anemia was observed in 4 % of patients and ≥G3 thrombocytopenia in 10 %. On multivariate analysis a higher PBM-V20 was associated with lower WBC nadir. Increased LSBM-V40 was correlated with a higher likelihood to develop ≥G3 HT. A cut-off point at 41 % for LSBM-V40 was found. Patients with LSBM-V40 ≥41 % were more likely to develop ≥G3 HT (55.3 vs. 32.4 %; p < 0.01). Conclusions. Increased low-dose to pelvic bony structures significantly predicted for WBC decrease. Medium-high dose to specific osseous subsites was associated with a higher probability of HT. LSBM-V40 was a strong predictor of ≥G3 HT. A threshold at 41 % for LSBM-V40 could be used to limit HT (AU)

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Dosimetric predictors of acute hematologic toxicity during concurrent intensity-modulated radiotherapy and chemotherapy for anal cancer.

PURPOSE: This study aimed at investigating whether the irradiated volume of pelvic bone marrow (PBM) and specific subsites may predict the occurrence of acute hematologic toxicity (HT) in anal cancer patients undergoing concurrent chemo-radiation. METHODS: 50 patients, submitted to IMRT and concurrent chemotherapy, were analyzed. Several bony structures were defined on planning-CT: PBM and lumbar-sacral (LSBM), lower pelvis (LPBM) and iliac (IBM) bone marrow. On dose-volume histograms, dosimetric parameters were taken. Endpoints included white blood-cell-count (WBC), absolute-neutrophil-count (ANC), hemoglobin (Hb) and platelet nadirs and acute hematologic toxicity (HT) according to RTOG scoring scale. Generalized linear modeling was used to find correlations between dosimetric variables and blood cell nadirs, while logistic regression analysis was used to test correlation with ≥G3 HT. Receiver Operating Characteristic (ROC) curve analysis was used to evaluate the optimal cut-off points for predictive dosimetric variables with the Youden method. RESULTS: Maximum detected acute HT comprised 38 % of ≥G3 leukopenia and 32 % of ≥G3 neutropenia. Grade 2 anemia was observed in 4 % of patients and ≥G3 thrombocytopenia in 10 %. On multivariate analysis a higher PBM-V 20 was associated with lower WBC nadir. Increased LSBM-V 40 was correlated with a higher likelihood to develop ≥G3 HT. A cut-off point at 41 % for LSBM-V 40 was found. Patients with LSBM-V 40 ≥41 % were more likely to develop ≥G3 HT (55.3 vs. 32.4 %; p < 0.01). CONCLUSIONS: Increased low-dose to pelvic bony structures significantly predicted for WBC decrease. Medium-high dose to specific osseous subsites was associated with a higher probability of HT. LSBM-V 40 was a strong predictor of ≥G3 HT. A threshold at 41 % for LSBM-V 40 could be used to limit HT.

Outcome predictors of treatment effectiveness for fungal malignant external otitis: a systematic review.

The aim of this review is to summarise literature data on clinical aspects and traditional management of fungal malignant external otitis (FMEO), and to identify potential predictive factors of positive treatment outcome. Articles were initially selected based on their titles or abstracts. Full articles were then retrieved and further scrutinised according to predetermined criteria. Reference lists of selected articles were searched for any missed publications. The selected articles were methodologically evaluated. Of an initial 143 references, 14 were selected that focalised on the management of FMEO. The majority of studies demonstrated a correlation between treatment effectiveness, assessed as symptom resolution, and clinical and management variables: abstention from surgical debridement, absence of facial palsy, Aspergillus spp. as causative pathogen and absence of imaging findings at diagnosis and follow-up. The effectiveness of FMEO treatment depends on the assessment of cranial nerve state, the causative pathogen and imaging findings. Above all, absence of facial nerve palsy, Aspergillus spp. and absence of radiological signs at diagnosis and during follow-up correlate with symptom resolution. The fact that conservative treatment may be associated with a better outcome than surgical debridement could purely reflect that patients with more aggressive and advanced illness required debridement, whereas milder disease was treated conservatively. Thus, caution should be advised in the interpretation of data due to the need for further trials on the topic.

The eminent anatomists who discovered the upper oesophageal sphincter.

OBJECTIVE: To discover the anatomist who first identified the upper oesophageal sphincter. METHOD: The authors searched dozens of antique anatomy textbooks kept in the old section of the 'Vincenzo Pinali' Medical Library of Padua University, looking for descriptions of the upper oesophageal sphincter. RESULTS: The oesophageal sphincter was drawn correctly only in 1601, by Julius Casserius, in the book De vocis auditusque organis historia anatomica… (which translates as 'An Anatomical History on the Organs of Voice and Hearing …'), and was properly described by Antonio Maria Valsalva in 1704 in the book De aure humana tractatus… ('Treatise on the Human Ear …'). CONCLUSION: Anatomists Casserius and Valsalva can be considered the discoverers of the 'oesophageal sphincter'.

N-butanol olfactory threshold and nasal patency before and after palatal expansion in children. A preliminary study.

OBJECTIVES: Olfaction is based on the function of the nasal olfactory receptors. Children can well detect and respond to odors in order to have information about food and environment. Rapid maxillary expansion seems to improve dental class and increase nasal patency correcting oral respiration in children. Nevertheless, there are no studies demonstrating that expansion in pediatric patients could influence olfactory sensitivity. The aim of this study was to evaluate olfactory threshold and nasal patency in children aged from 6 to 12 years before and after rapid maxillary expansion. METHOD: N-butanol olfactory thresholds, anterior active rhinomanometry, and peak nasal inspiratory flow were measured in 12 children (6-12 years) before (T0), 20 days (T1), and 6 months after rapid maxillary expansion application (T2). RESULTS: A significant lower olfactory threshold was found comparing T2 and T0 N-butanol olfactory threshold values (p=0.038). Peak nasal inspiratory flow showed a significant improvement both at T1 and T2, with respect to T0 values (p=0.043 and p=0.0001, respectively). T2 nasal resistances showed a trend towards a significant reduction when compared with T1 values (p=0.15). CONCLUSION: This pilot study suggested that rapid maxillary expansion may lead to improved N-butanol olfactory thresholds, at least 6 months after palatal expansion. Furthermore, rapid maxillary expansion seems to improve peak nasal inspiratory flow values, and finally although with lower sensitivity, reduce nasal resistances as measured by rhinomanometry.

Case report of cholesteatoma recurrence with Bezold's abscess presenting as a deep neck infection.

Cervical masses are a common clinical finding, but differential diagnosis is often challenging. Acute neck swellings are often due to deep cervical space infections that have originated at oral or oropharyngeal sites. Deep neck infections originating elsewhere are not rare; however, they are difficult to diagnose, and their origins remain obscure in 20% of cases. Neck swellings that originate in the middle ear are very rare, with only a few reported in the scientific literature. Here we report an atypical case of Bezold's abscess caused by the recurrence of a middle ear cholesteatoma. In patients with neck swelling and a history of primary cholesteatoma of the middle ear, otolaryngologists should consider regional recurrence of disease a possibility even several years after the primary surgery.

The superior laryngeal nerve injury of a famous soprano, Amelita Galli-Curci.

The superior laryngeal nerve (SLN) has been attributed much less clinical significance than the recurrent laryngeal nerve. It has sometimes been described as the 'neglected' nerve in thyroid surgery, although injury to this nerve can cause significant disability. The external branch of the SLN is the only motor supply to the cricothyroid muscle, which increases the tension of the ipsilateral vocal fold during highfrequency phonation, particularly in women and voice professionals. Damage to this nerve can manifest as ipsilateral cricothyroid muscle paralysis, and clinical symptoms may include a hoarse, breathy voice, frequent throat clearing, vocal fatigue or diminished vocal frequency range, especially when rising pitch. SLN paralysis can be a significant issue for those whose careers depend largely on a full range of voice. The famous opera soprano, Amelita Galli-Curci, suffered SLN injury during thyroid surgery with distressing consequences.

Tracking target position variability using intraprostatic fiducial markers and electronic portal imaging in prostate cancer radiotherapy.

PURPOSE: Modern radiotherapy has achieved substantial improvement in tumour control and toxicity rates by escalating the total dose to the target volume while sparing surrounding normal tissues. It has therefore become necessary to precisely track tumour position in order to minimise geometrical uncertainties due to setup errors and organ motion. We conducted this prospective evaluation of prostate cancer patients treated with image-guided conformal radiation therapy at our institution. We implanted three fiducial markers (gold seeds) within the prostatic gland in order to quantify daily target displacements and to generate specific margins around the clinical target volume (CTV) to create an appropriate planned target volume (PTV). MATERIALS AND METHODS: Between April and December 2009, ten patients affected with localised prostate cancer were transrectally implanted with three radio-opaque markers. Each patient underwent a computed tomography (CT) scan for planning purposes following proper bladder and rectum preparation. During treatment two orthogonal images were acquired daily and compared with previously generated digitally reconstructed radiographs. After manual localisation, comparison between the position of the gold seeds on the portal and reference images was carried out, and a set of extrapolated lateral-lateral (LL), anterior-posterior (AP) and cranial-caudal (CC) shift corrections was calculated and recorded. Couch corrections were applied with a threshold of 3 mm displacement. RESULTS: Systematic and random errors for each direction were calculated either as measured according to displacement of the gold seeds prior to any couch movement and after couch position correction according to the radio-opaque markers. For skin marks, mean systematic and random errors were 0.12+2.94 mm for LL, 1.04+3.37 mm for AP, -1.14+2.71 mm for CC, whereas for seed markers, mean and systematic errors were 0.6+1.5 mm for LL, 0.51+2.45 mm for AP and -0.25+2.51 mm for CC. A scatter plot generated on all measurements after couch repositioning according to gold-seed displacement suggested a confidence range of shift distributions within 5 mm for LL, 8 mm for CC, and 7 mm for AP. The total systematic and random components were then used to calculate proper PTV in patients receiving conventional treatment (7 mm for LL and 9 mm for both AP and CC). CONCLUSIONS: Prostate positional variability during a course of radiation treatment is strongly influenced by setup and organ motion. Organ tracking through fiducial markers and electronic portal imaging is able to reduce the spread of displacements, significantly contributing to improve the ballistic precision of radiation delivery.

Efficacy and feasibility of induction chemotherapy and radiotherapy plus cetuximab in head and neck cancer.

BACKGROUND: To determine the potential activity and tolerability of sequential treatment in head and neck cancer, we conducted a phase II trial based on induction chemotherapy of two cycles of taxotere, cisplatin and 5-fluorouracil followed by radiotherapy plus weekly cetuximab. PATIENTS AND METHODS: Thirty-six patients with stage III or IV squamous cell carcinoma of the oral cavity, larynx, oropharynx and hypopharynx were treated and evaluated for response and acute toxicity. RESULTS: Eighty-one percent of patients had stage IV disease and 42% had hypopharyngeal and oral cavity primaries. The overall response rate was 81.8%, with 60.6% complete response and 33.3% partial response. Severe toxicities were febrile neutropenia (6%) during induction chemotherapy and dermatitis (48%), mucositis (33%) and dysphagia (12%) during the concurrent phase. CONCLUSION: Our protocol proved to be feasible, effective and well tolerated. This sequential strategy should be further investigated.

Concomitant adjuvant chemoradiotherapy with weekly low-dose cisplatin for high-risk squamous cell carcinoma of the head and neck: a phase II prospective trial.

AIMS: Several randomised trials have tested adjuvant regimens using concomitant high-dose cisplatin and radiotherapy to improve outcome in high-risk locally advanced squamous cell head and neck cancer (HNSCC), showing a substantial increase in locoregional control and disease-free survival, despite a higher and eventually detrimental toxicity profile. The aim of the present phase II single-stage prospective study was to investigate whether a weekly cisplatin-based chemoradiotherapy regimen might be able to improve patients' compliance compared with standard-dose cisplatin with similar outcome results. MATERIALS AND METHODS: Between January 2004 and November 2008, 54 patients with high-risk locally advanced HNSCC were enrolled on to this phase II trial. Patient characteristics were: median age 59.7 years, Eastern Cooperative Oncology Group performance status 1 in 72% of patients and stage IV disease in 82%, extracapsular nodal spread in 67% and positive/close surgical margins in 37%. Patients received cisplatin (30 mg/m(2)) once a week for 7-8 weeks concurrent with external beam radiotherapy delivered with a median dose of 66.6 Gy (1.8 Gy each day; five fractions/week) on the primary site and 50 Gy (2 Gy each day) for the lower neck. RESULTS: Major acute toxicity of the combined treatment, defined as grade 3-4 mucositis, was observed in 35.2% of patients. No fatal complications occurred, with 81.5% of patients completing the planned regimen. Late reactions were mild (total 16% with a grade 3 dysphagia rate of 12%). The locoregional control rate was 82%; 5 year overall and disease-free survival were 63 and 62%, respectively. CONCLUSIONS: Concomitant adjuvant chemoradiotherapy with weekly cisplatin seems to be a feasible and well-tolerated therapeutic approach in 'unfit' patients. Clinical results seem to be at least comparable with those previously reported. However, to draw any definitive conclusion, large confirmatory phase III randomised trials are demanded.

Botulinum toxin improves dysphagia associated with multiple sclerosis.

OBJECTIVE: To evaluate the efficacy of botulinum neurotoxin type A (BoNT/A) for severe oro-pharyngeal dysphagia associated with multiple sclerosis (MS). PATIENTS AND METHODS: BoNT/A was injected percutaneously into the hyperactive cricopharyngeal muscle of 14 dysphagic MS patients under electromyographic control. Patients were evaluated by videofluoroscopic and electromyographic examinations and by the Penetration/Aspiration Scale (PAS), at week 1, 4, 12, 16, 18, and 24 after BoNT/A injection. RESULTS: All patients showed a significant improvement in all the swallowing outcome measures. CONCLUSION: No specific treatment for oro-pharyngeal dysphagia related to MS has been described to date. Our preliminary findings suggest a potential benefit from BoNT/A treatment in MS patients with dysphagia associated with upper esophageal sphincter hyperactivity.

Anosmia associated with hearing loss and benign positional vertigo after head trauma.

It is well known that head trauma may cause hearing loss, which can be either conductive or sensorineural. Benign paroxysmal positional vertigo and olfactory dysfunction due to head trauma are also well known. The association between sensorineural hearing loss and anosmia, following head trauma, is extremely rare. Two rare cases of post-traumatic occurrence of hearing loss, olfactory dysfunction and benign positional vertigo are reported and the pathophysiology of the association between sensorineural hearing loss, anosmia and benign paroxysmal positional vertigo, after head injury, are briefly discussed. ENT specialists should, in the authors' opinion, be aware of the possible association between anosmia, sensorineural hearing loss and benign paroxysmal positional vertigo after head injury, even in the absence of skull fracture.