PURPOSE: Among RF pulses, a sinc pulse is typically used for slice selection due to its frequency-selective feature. When a sinc pulse is implemented in practice, it needs to be apodized to avoid truncation artifacts at the expense of broadening the transition region of the excited-band profile. Here a sinc pulse tailored by a new apodization function is proposed that produces a sharper transition region with well suppression of truncation artifacts in comparison with conventional tailored sinc pulses. A multiband pulse designed using this newly apodized sinc pulse is also suggested inheriting the better performance of the newly apodized sinc pulse. MATERIALS AND METHODS: A new apodization function is introduced to taper a sinc pulse, playing a role to slightly shift the first zero-crossing of a tailored sinc pulse from the peak of the main lobe and thereby producing a narrower bandwidth as well as a sharper pass-band in the excitation profile. The newly apodized sinc pulse was also utilized to design a multiband pulse which inherits the performance of its constituent. Performances of the proposed sinc pulse and the multiband pulse generated with it were demonstrated by Bloch simulation and phantom imaging. RESULTS: In both simulations and experiments, the newly apodized sinc pulse yielded a narrower bandwidth and a sharper transition of the pass-band profile with a desirable degree of side-lobe suppression than the commonly used Hanning-windowed sinc pulse. The multiband pulse designed using the newly apodized sinc pulse also showed the better performance in multi-slice excitation than the one designed with the Hanning-windowed sinc pulse. CONCLUSION: The new tailored sinc pulse proposed here provides a better performance in slice (or slab) selection than conventional tailored sinc pulses. Thanks to the availability of analytical expression, it can also be utilized for multiband pulse design with great flexibility and readiness in implementation, transferring its better performance.
Artifacts ; Pliability

OBJECTIVE: To preliminarily evaluate technical feasibility of a dual-echo ultrashort echo time (UTE) subtraction MR imaging by using concurrent dephasing and excitation (CODE) sequence for visualization of iron-oxide enhancement in focal inflammatory pulmonary lesions. MATERIALS AND METHODS: A UTE pulmonary MR imaging before and after the injection of clinically usable superparamagnetic iron-oxide nanoparticles, ferumoxytol, was conducted using CODE sequence with dual echo times of 0.14 ms for the first echo and 4.15 ms for the second echo on 3T scanner in two rabbits concurrently having granulomatous lung disease and lung cancer in separate lobes. A mean ratio of standardized signal intensity (SI) was calculated for comparison of granulomatous lesion and cancer at first echo, second echo, and subtracted images. Lesions were pathologically evaluated with Prussian blue and immunohistochemistry staining. RESULTS: Post-contrast subtracted CODE images visualized exclusive enhancement of iron oxide in granulomatous disease, but not in the cancer (mean ratio of SI, 2.15 ± 0.68 for granulomatous lesion versus 1.00 ± 0.07 for cancer; p value = 0.002). Prussian blue and corresponding anti-rabbit macrophage IgG-staining suggested an intracellular uptake of iron-oxide nanoparticles in macrophages of granulomatous lesions. CONCLUSION: Dual-echo UTE subtraction MR imaging using CODE sequence depicts an exclusive positive enhancement of iron-oxide nanoparticle in rabbits in focal granulomatous inflammatory lesions.
Ferrosoferric Oxide ; Granuloma ; Immunohistochemistry ; Iron ; Lung Diseases ; Lung Neoplasms ; Macrophages ; Magnetic Resonance Imaging ; Nanoparticles ; Rabbits

BACKGROUND AND OBJECTIVES: High dorsal deflection of the nasal septum around cartilage or the perpendicular plate is technically difficult to correct. The objective of this study was to assess whether correction of high septal deviation during septoplasty is necessary to improve nasal airflow. PATIENTS AND SURGICAL METHOD: Twenty-one patients with high septal deviation around the septal cartilage or the perpendicular plate were included in this study. In order to improve nasal obstruction, septoturbinoplasty was performed, but high septal deviation was not corrected. Subjective and objective improvements were evaluated using the visual analogue scale and acoustic rhinometry 1 month before and 3 months after surgery. RESULTS: After correction of nasal septum deviation except high septal deviation and reduction of turbinate mucosal volume, postoperative nasal volume and minimum cross-sectional area were significantly increased. Subjective symptom scales for nasal obstruction, rhinorrhea, sneezing, and posterior nasal drip were considerably improved after limited septoturbinoplasty in patients who still had high dorsal deflection of the nasal septum. CONCLUSION: Our findings suggest that limited septoturbinoplasty without excessive resection of high dorsal deflection of the nasal septum can improve nasal airflow and reduce subjective symptoms, including nasal obstruction.
Cartilage ; Humans ; Methods ; Nasal Obstruction* ; Nasal Septum ; Rhinometry, Acoustic ; Sneezing ; Turbinates ; Weights and Measures

BACKGROUND AND OBJECTIVES: The clinical significance and need for the treatment of primary snoring and mild obstructive sleep apnea have been recently questioned. In this study, we analyzed therapeutic outcome and the methods of treatment of such diseases. SUBJECTS AND METHOD: A retrospective review was conducted using the medical records of patients diagnosed with primary snoring or mild obstructive sleep apnea at a single institution from 2013 to 2015 through polysomnography or WATCHPAT. RESULTS: Of the 18 patients (37%) with primary snoring, 13 patients (72.2%) underwent surgery, four patients (22.2%) were treated with surgery and mandibular advancement device, and one patient (5.6%) underwent automatic positive airway pressure therapy. Of the 78 patients (61%) with mild obstructive sleep apnea, 35 patients (44.8%) had surgery, 24 patients (30.8%) were treated with mandibular advancement device, 13 patients (16.7%) were treated with surgery and mandibular advancement device and 6 patients (7.7%) received automatic positive airway pressure therapy. For primary snoring, while Epworth Sleepiness Scale and Pittsburg Sleep Quality Index did not improve, the snoring visual analog scale decreased significantly. In patients with mild obstructive sleep apnea, Apnea-Hypopnea Index, snoring decibel, Epworth Sleepiness Scale, and Pittsburg Sleep Quality Index were significantly decreased after treatment and the lowest oxygen saturation was significantly increased after treatment. CONCLUSION: For primary snoring, the direction of treatment should be determined in accordance with the presence of associated diseases related to sleep disturbance breathing. For mild obstructive sleep apnea, active treatment may be helpful.
Humans ; Mandibular Advancement ; Medical Records ; Methods ; Oxygen ; Polysomnography ; Respiration ; Retrospective Studies ; Sleep Apnea, Obstructive ; Snoring ; Visual Analog Scale

BACKGROUND AND OBJECTIVES: The clinical significance and need for the treatment of primary snoring and mild obstructive sleep apnea have been recently questioned. In this study, we analyzed therapeutic outcome and the methods of treatment of such diseases.SUBJECTS AND METHOD: A retrospective review was conducted using the medical records of patients diagnosed with primary snoring or mild obstructive sleep apnea at a single institution from 2013 to 2015 through polysomnography or WATCHPAT. RESULTS: Of the 18 patients (37%) with primary snoring, 13 patients (72.2%) underwent surgery, four patients (22.2%) were treated with surgery and mandibular advancement device, and one patient (5.6%) underwent automatic positive airway pressure therapy. Of the 78 patients (61%) with mild obstructive sleep apnea, 35 patients (44.8%) had surgery, 24 patients (30.8%) were treated with mandibular advancement device, 13 patients (16.7%) were treated with surgery and mandibular advancement device and 6 patients (7.7%) received automatic positive airway pressure therapy. For primary snoring, while Epworth Sleepiness Scale and Pittsburg Sleep Quality Index did not improve, the snoring visual analog scale decreased significantly. In patients with mild obstructive sleep apnea, Apnea-Hypopnea Index, snoring decibel, Epworth Sleepiness Scale, and Pittsburg Sleep Quality Index were significantly decreased after treatment and the lowest oxygen saturation was significantly increased after treatment. CONCLUSION For primary snoring, the direction of treatment should be determined in accordance with the presence of associated diseases related to sleep disturbance breathing. For mild obstructive sleep apnea, active treatment may be helpful.