ABSTRACT
Objective To investigate the feasibility of detector array in Monaco modeling for MLC parameters adjustment.Methods One parameter was fixed, and then the other parameter was changed.The γ pass rates of the test beams, namely 3ABUT, 7SegA, and FOUR L, were assessed to determine the values of leaf transmission and leaf offset.A total of 12 tumor cases from different anatomical sites were randomly selected.Two-dimensional dose verification (rack angle zero) of Step& Shot and dMLC plans as well as three-dimensional dose validation of VMAT plan were performed using Octavius 4D system.The γ pass rates were analyzed at a standard of 3%/3 mm.Meanwhile, the point dose verification for these three plans was analyzed to obtain the dose deviations.Results The values of leaf transmission and leaf offset were 0.0105 and-0.08 mm, respectively.The average γ pass rates (%) of Step& Shot, dMLC, and VMAT plans were 88.59±2.94, 87.81±3.28, and 87.45±2.24 before adjustment and 98.45±1.23, 98.9±1.01, and 96.03±1.66 after adjustment.In addition, the average dose deviations (%) according to the point dose verification were 0.85±0.75, 0.95±0.39, and 0.98±0.40 before adjustment and 0.97±0.57, 1.08±0.76, and 0.86±0.45 after adjustment.Conclusions Octavius detector 729 ionization chamber array is a feasible and reliable device in Monaco modeling for MLC parameters adjustment.
ABSTRACT
Objective To investigate the gamma (γ) passing rates for volumetric-modulated arc therapy (VMAT) dosimetric verification with different techniques.Methods A total of 12 VMAT plans for the treatment of different anatomical sites in cancer patients were chosen.The Octavius 4D system was used to measure the dose distributions in two different settings:the gantry was rotating (three-dimensional (3D) and 2D γ-analysis) and the gantry was fixed at 0°(2D γ-analysis).The γ passing rates were analyzed with 3%/3 mm and 2%/2 mm criteria, using the paired t test or Wilcoxon signed-rank test.The 2D γ passing rates for different irradiation methods were calculated.Results For the 3D and 2D dose distributions obtained at a rotating gantry angle as well as the 2D dose distribution obtained at zero gantry angle, the average γ passing rates were 96.03%, 96.98%, and 98.90% for 3%/3 mm (P=0.227, P=0.000, P=0.003);82.08%, 84.04%, and 90.90% for 2%/2 mm (P=0.379, P=0.000, P=0.000).For the 2D dose distributions obtained with different irradiation methods, the average γ passing rate was 98.99% for 3%/3 mm and 93.68% for 2%/2 mm.Conclusions The VMAT dosimetric verification based on a 3D volumetric dosimeter at a rotating gantry position can be clinically useful for delivery quality assurance (QA), and can achieve the most reliable dose calculation for VMAT, which has more referential values.
ABSTRACT
Objective To investigate the clinucal value of the application of supporting laryngoscope combined laryngeal endoscope in excision for benign lesions of vocal cords.Methods 124 cases with benign lesions of vocal cords were resected under supporting laryngoscope combined larygeal endoscope,the effectiveness of surgical procedures were observed and evaluated.Results Lesions in all cases were resected successfully,mucosa of vocal cords returned to their normal state in all cases when observed through layngofiberscope.Vocal quality was significantly improved in 122 cases.Conclesion The application of supporting laryngoscope combined larygeal endoscope could provide a wild and clear sight,and make the exact procedure and minimal trauma in excision for benign lesions of vocal cords become possible.
ABSTRACT
Objective To discuss how to choose the method of anesthetization for childhood obstructive sleep apnea hypopnea syndrome(OSAHS).Methods 98 children with tonsillar and adenoidal hypertrophy were seleted,and were randomly divided into two groups.Tonsillectomy and adenoidectomy were performed for the group with local infiltration anesthesia,while Tonsil dissection and endoscopic-assisted adenoidectomy through nose were for the group with intravenous general anesthesia.Then blood loss,operation time,intake time,operation damage,psychological trau-ma,hospitalization fares and operative efficacy were compared.Results The group with general anesthesia lost more blood,underwent longer operations with higher cost;the group with local anesthesia had more operation damage,grea-ter psyhologieal trauma and sometimes general anesthesia was necessary for the children who didn't cooperate.But these two methods of anesthetization almost had the same operative efficacy,and the symptoms such as snoring,oral breathing and suffocating were significantly improved after surgery.Condusion Every method had own advantages and disadvantages.Local anesthesia was as effective as general anesthesia in treating childhood OSAHS.but the anes-thetization choice should vary with the situations.
ABSTRACT
Objective To explore the clinical efficacy of endoscopic sinus surgery on the treatment of non-invasive fangal the maxillary sinusitis. Methods 21 patients with non-invasive fungal maxillary sinusitis patients were given endoscopic sinus surgery. Completely remove of the nasal cavity and sinus disease, fully open, washing si-nusos and give nasal endoscopy on a regular fine. Results Follow-up of 6 months to 4 years,18 cases of cure,1 case of loss of information. 2 case of relapse. Cases of recurrence were cured by endoscopic sinus dressing. Conclusion Endoseopie sinus surgery is an effective measure on trentment of non-invasive fungal maxillary sinuses.