Selection rule for cavity configurations to generate cylindrical vector beams with low beam quality factor.

Considering the birefringence of the gain medium, we propose a selection rule for designing cavity configurations that enable the generation of radially and azimuthally polarized laser beams with a low beam quality factor, i.e., high beam quality. Using this rule, all stable regions can support cylindrical vector (CV) beams by using the position of the end mirror as the tuning parameter to vary the cavity configuration. Such cavity configurations tend to sustain the fundamental or lowest-order CV beam, and radially or azimuthally polarized beams can be obtained simply by varying the tuning parameter. Based on experimental measurements of the beam quality factor and polarization characteristics, we verified our analyses and simulations for a four-element laser system.

Respiratory insufficiency from myasthenia gravis and polymyositis due to malignant thymoma triggering Takotsubo syndrome.

BACKGROUND: Takotsubo syndrome (TTS) is a non-ischaemic cardiomyopathy with sudden but transient systolic dysfunction. TTS mimics myocardial infarction clinically, chemically, and electrocardiographically but echocardiography typically shows apical ballooning and coronary angiography is normal. TTS has not been reported in a patient with myasthenia gravis (MG) and polymyositis due to a malignant thymoma. CASE REPORT: Two weeks prior to admission, a 76-year-old female developed dysarthria, chronic coughing and disabling myalgias of the entire musculature. Since there was hyper-CKemia and elevated troponin, myocardial infarction was suspected. During swallowing of the antithrombotic medication on admission, she experienced apnoea, requiring cardio-pulmonary resuscitation with intubation and mechanical ventilation. Further diagnostic work-up precluded coronary heart disease but revealed TTS. Upon neurologic work-up, MG and polymyositis were diagnosed but the response to cholinergic drugs and plasmapheresis was poor. TTS was attributed to stress and anxiety from MG-associated respiratory insufficiency. The further course was complicated by recurrent supraventricular bradyarrhythmias and respiratory insufficiency. Upon thoracic CT a thymoma was suspected. Two months after admission, the mediastinal tumour was resected and malignant thymoma WHO BII infiltrating the mediastinum (modified Masaoka-Koga II/2) was diagnosed. CONCLUSIONS: This case shows that TTS may be triggered by stress from respiratory insufficiency during a myasthenic crisis, MG may be associated with polymyositis, cholinergic medication may trigger bradyarrhythmias, and cholinergic drugs and plasmapheresis may exhibit a poor effect if malignant thymoma and polymyositis are present.

A rare case of tracheal squamous cell carcinoma presented with critical airway obstruction.

Tracheal squamous cell carcinoma is a rare and potentially fatal thoracic cancer mimicking common airway disorders. Accurate diagnosis requires a detailed history, thorough physical examination, and high clinical suspicion.

Balloon Dilation Eustachian Tuboplasty for Dilatory Dysfunction With and Without Effusion: A Comprehensive Outcome Analysis.

OBJECTIVE: This study aimed (1) to demonstrate the efficacy of balloon dilation Eustachian tuboplasty (BDET) for dilatory Eustachian tube dysfunction (ETD) and (2) to determine whether adjunctive ventilation tube insertion (VTI) is superior to myringotomy in relieving symptoms for patients with ETD and concurrent middle ear effusion (MEE) treated with BDET. STUDY DESIGN: A retrospective cohort study. SETTING: Tertiary care academic center. METHODS: Patients with dilatory ETD undergoing BDET with a ≥6-month follow-up period were enrolled and evaluated mainly using Eustachian tube function (ETF) tests and Eustachian Tube Dysfunction Questionnaire-7 (ETDQ-7). Participants with concurrent MEE were further classified into 2 subgroups, BDET with VTI and BDET with myringotomy. An intergroup comparison and comprehensive outcome evaluation were performed. RESULTS: In total, 35 patients with 50 symptomatic ears were enrolled. According to ETF test results, the normalized ETF rate was 94% on the last visit. The mean ETDQ-7 scores decreased significantly from 3.7 ± 1.4 to 2.0 ± 0.9 after interventions, with the most improvement in symptoms occurring for "ear fullness" and "muffled hearing." For the final visit, strong correlations among ETF tests, tympanometry, and Valsalva results were noted. The aforementioned assessment results did not significantly differ between (1) the patients with MEE and patients without MEE and (2) "BDET with VTI" subgroup and "BDET with myringotomy" subgroup. CONCLUSION: BDET was effective for dilatory ETD, even in cases with concurrent MEE. For patients with ETD and MEE, further research is required to evaluate the benefits of adjunctive myringotomy with or without VTI.

Evaluation of Fine Needle Aspiration Cytopathology in Salivary Gland Tumors under Milan System: Challenges, Misdiagnosis Rates, and Clinical Recommendations.

(1) Background: Salivary gland tumors are rare in the head and neck. To determine the need and extent of surgical intervention, fine needle aspiration (FNA) is a widely accepted tool to approach salivary gland lesions. However, the FNA cytology varies between entities, while the lack of uniform terminology makes diagnosis more challenging. Since establishing the Milan system for reporting salivary gland cytopathology (MSRSGC) has become an increasingly accepted reporting standard, further examination and detailed recommendations were needed. (2) Methods: Between April 2013 and October 2021, 375 cases with FNA and salivary gland resection were retrospectively collected. All FNA specimens were reclassified according to the criteria of MSRSGC. After surgical excision, the FNA data were compared with the histological diagnosis to estimate the risk of malignancy (ROM), the risk of neoplasm (RON), and the diagnostic accuracy for each diagnostic category. (3) Results: Our cohort's distribution of ROM and RON was similar to the MSRSGC's recommendation. Carcinoma ex pleomorphic adenoma (CXPA) has the highest rate (66.7%) of misdiagnosed as a nonneoplastic lesion or benign salivary gland tumor. Pleomorphic adenoma (PA) and Warthin's tumor were the most common benign salivary gland tumors, while the cytology diagnosis of Warthin's tumor seems more challenging than PAs. (4) Conclusions: Despite the convenience and effectiveness of MSRSGC, we suggest close follow-up, re-biopsy, or surgical removal for salivary lesions even in Milan IVA-Benign for possibly missing FNA of malignancy, mixed lesions, or prevention of malignant transformation.

Effect of music on patients with cardiovascular diseases and during cardiovascular interventions : A systematic review.

BACKGROUND: The therapeutic effects of music have been known for thousands of years. Recently, studies with music interventions in patients with cardiovascular diseases yielded controversial results. The aim of this review is to provide an overview of the effects of receptive music intervention on the cardiovascular system. METHODS: We searched in PubMed, SCOPUS and CENTRAL for publications between January 1980 and May 2018. Primary endpoints were heart rate, heart rate variability and blood pressure. Secondary endpoints comprised respiratory rate, anxiety and pain. The quality of the studies was assessed by using the CONSORT statement and the Cochrane risk of bias assessment tool. A meta-analysis and subgroup analyses concerning music style, gender and region were planned. RESULTS: A total of 29 studies comprising 2579 patients were included and 18 studies with 1758 patients investigated the effect of music on patients undergoing coronary angiography or open heart surgery. Other studies applied music to children with congenital heart diseases, pregnant women with hypertension or patients with unstable angina. Due to high methodological study heterogeneity, a meta-analysis was not performed. The study quality was assessed as medium to low. In ten studies with higher quality comprising 1054 patients, music intervention was not associated with significant changes in the cardiovascular endpoints compared to the control group. The subgroup analyses did not demonstrate any relevant results. CONCLUSION: Currently no definite effect of receptive music intervention on the cardiovascular system can be verified. Further research is needed to assess music as an inexpensive and easy applicable form of therapy.