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71.
RATIONALE AND OBJECTIVES: The aim of this study was to test the effectiveness of laser-hyperpolarized helium 3 (3He) as a contrast agent for magnetic resonance (MR) imaging of porcine paranasal sinuses. MATERIALS AND METHODS: Imaging experiments were conducted on the heads of four 50-kg Yorkshire pigs after open sinus surgery was performed. Paranasal sinus MR images were obtained with laser-polarized 3He gas produced through the spin-exchange method. The gas was delivered into the sinuses through two 14-gauge plastic catheters inserted in the nostrils. The 3He MR images were then compared with spatially correlated proton MR images. RESULTS: The porcine paranasal sinuses were adequately depicted by MR imaging with hyperpolarized 3He. The signal intensity of the paranasal sinuses on the 3He MR images was related to the size of the opening joining the sinuses to the nasal cavity and was clearly time dependent. CONCLUSION: Hyperpolarized 3He MR imaging may be particularly useful for identifying the anatomic configuration of the paranasal sinuses, as well as for assessing sinus aeration. Further study of the time-dependence of 3He signal intensity may help increase understanding of gas exchange in the sinuses. 相似文献
72.
Solitary extramedullary plasmacytoma is a rare tumour with radiotherapy playing an important role in its management. This report describes the case history of a man with a solitary extramedullary plasmacytoma at an extremely rare site, the premaxilla, that posed certain diagnostic and therapeutic dilemmas. The patient underwent surgery followed by postoperative radiotherapy. The use of two modalities of treatment for this localized tumour has been justified by briefly reviewing the literature and defining the various prognostic factors. These prognostic factors in turn should guide the treatment of these uncommon tumours. 相似文献
73.
74.
The effect of surfactants on the skin penetration of diazepam 总被引:10,自引:0,他引:10
Shokri J Nokhodchi A Dashbolaghi A Hassan-Zadeh D Ghafourian T Barzegar Jalali M 《International journal of pharmaceutics》2001,228(1-2):99-107
The percutaneous permeation of diazepam was investigated in rat skin after application of a water-propylene glycol (50:50% v/v) using a diffusion cell technique. The effect of various surfactants (sodium lauryl sulfate (SLS), cetyltrimethylammonium bromide (CTAB), benzalkonium chloride or Tween 80) with different concentrations on skin permeability were evaluated. Flux, K(p), lag time and enhancement ratios (ERs) of diazepam were measured over 10 h and compared with control sample (containing no surfactant). Furthermore, diazepam solubility in presence of surfactants was determined. The in vitro permeation experiments with rat skin revealed that the surfactant enhancers varied in their ability to enhance the flux of diazepam. Benzalkonium chloride which possessed the highest lipophilicity (logP=1.9) among cationic surfactants provided the greatest enhancement for diazepam flux (7.98-fold over control). CTAB (logP<1) at a concentration of 1% w/w exhibited no significant increase in flux of diazepam compared to control (1.16-fold over control). The results also showed that the highest ER was obtained in presence of 1% w/w surfactant with the exception of SLS and CTAB. The increase in flux at low enhancer concentrations is normally attributed to the ability of the surfactant molecules to penetrate the skin and increase its permeability. Reduction in the rate of transport of the drug present in enhancer systems beyond 1% w/w is attributed to the ability of the surfactant to form micelles and is normally observed only if interaction between micelle and the drug occurs. The results showed that the nature of enhancer greatly influences cutaneous barrier impairment. 相似文献
75.
Sahraoui S Zamiati S Essaidi M Jalali K Acharki A Ouhtatou F Benchekroun N Tahri A Benider A Sqalli S Benchekroun Y Kahlain A 《Revue de laryngologie - otologie - rhinologie》2000,121(3):161-163
Cancer of a thyroglossal duct cyst is very rare. Clinical presentation is identical that of a benign cyst, and the diagnosis is histopathological. We report the case of 36 year-old woman treated for papillary carcinoma of a thyroglossal duct cyst. The treatment was surgical excision according Sistrunk method. There was no distant spread. After 22 months follow up, the patient is alive, with no signs of recurrence. 相似文献
76.
Divya Balakrishnan Vinod Mukundaprasad Subhadra Jalali Rajeev Reddy Pappuru 《Seminars in ophthalmology》2018,33(4):576-580
Purpose: To compare the surgical outcomes of glued intraocular lens (GIOL) and sutured scleral fixated intraocular lens (SFIOL) implantation. Methods: A retrospective, interventional case series of 60 patients (68 eyes) who underwent GIOL (28 eyes: 11 primary; 17 secondary) and SFIOL (40 eyes: 24 primary; 16 secondary) in a tertiary eye care institute was done. The main outcome measures were complications, time taken for surgery, postoperative refractive outcomes, and final best-corrected visual acuity (BCVA). Results: The mean final BCVA was 0.42 (20/40) (+/– SD 0.29) in the GIOL group and 0.57 (20/50) (+/– SD 0.48) in the SFIOL group (p=0.08). The time taken for primary GIOL (mean+/– SD: 66+/–19 minutes) was significantly lower than primary SFIOL (means+/–SD: 94+/–34 minutes) (p=0.006). The complications were comparable between the GIOL (25%) and SFIOL (15%) groups (p=0.30). The most common complication noted was transient vitreous hemorrhage (GIOL 17%, SFIOL 5%). The only sight-threatening complication seen was retinal detachment, with one eye in each group. The mean follow-up was 20 (GIOL) and 20.4 weeks (SFIOL). Conclusion: Both glued intraocular lens and sutured scleral fixated intraocular lens are safe and effective procedures in cases of insufficient capsular support. In view of the shorter surgical time with similar outcomes, primary GIOL can be considered as a preferred surgical option over primary SFIOL. 相似文献
77.
Ashwini Budrukkar Rakesh Jalali Debnarayan Dutta Rajiv Sarin Rashmi Devlekar Sachin Parab Anagha Kakde 《Journal of neuro-oncology》2009,95(3):413-419
The aim of this article is to evaluate and assess the impact of various factors on quality of life (QOL) in adult patients
with primary brain tumors seen consecutively in routine neurooncology practice. Two hundred and fifty-seven adult patients,
after undergoing surgical intervention and histologically proven primary brain neoplasms were registered in the NeuroOncology
Clinic at our centre during 1 full calendar year. The study included detailed neurological assessment, evaluation of QOL using
EORTC questionnaire (QLQ-30) and specific Brain Cancer module (BN 20). In the present analysis, QOL scores before starting
adjuvant treatment were measured and impact of patient and tumor related factors were analyzed. Baseline global QOL data of
all patients (available in 243) was relatively low including in all histological tumor types. Physical function, role function,
emotion function, cognitive and social function scores were 80, 78, 65.7, 70 and 70.5 (higher values better), respectively.
Domains of future uncertainty, visual disorder, motor deficit, communication deficit, headache, seizures and drowsiness scores
were 19.6, 18.2, 28.5, 30.7, 21, 31.8 and 16 (lower values better), respectively. Elderly patients had poorer global score
(21 points difference; p = 0.161). Patients with lower performance status (KPS < 70) had a lower global QOL (KPS ≥ 80 vs. ≤ 70; 37 vs. 67; p = 0.001) including in all histological types of high-grade gliomas (HGG) (p = 0.005), low-grade gliomas (LGG) (p = 0.04) and benign tumors (p = <0.001). Illiterate patients had lower QOL score (p = 0.005). Tumor type is an important patient related factor that influences baseline global scores (LGG vs. HGG 62 and 52;
p = 0.015). Economic status significantly influence QOL scores in HGG (p = 0.052). Type of surgery (biopsy/complete excision) (p = 0.284) and site of tumor (p = 0.309) did not show any impact on QOL score. Patients with primary brain tumours before starting adjuvant therapy have
relatively low baseline quality of life scores, especially in lower economic and literacy strata. Patients with malignant
tumors and poor performance status had significantly lower QOL scores even before starting adjuvant treatment. 相似文献
78.
79.
Meniscal injuries: detection using MR imaging 总被引:15,自引:0,他引:15
Reicher MA; Hartzman S; Duckwiler GR; Bassett LW; Anderson LJ; Gold RH 《Radiology》1986,159(3):753-757
Both retrospective and blinded analyses of thin-section, high-resolution magnetic resonance (MR) images of the knee joint, produced using a solenoid surface coil, indicate that MR imaging is an effective technique for evaluating meniscal injuries. Images of 49 patients were evaluated, and the results were correlated with those of subsequent arthroscopy. A grading scale was developed to rate the index of suspicion of a meniscal tear based on the MR images. Overall, approximately 80% of menisci rated grade 4 (definite tear) or 3 (probable tear) were found to have corresponding tears at arthroscopy. In many other patients with a grade 4 or 3 meniscus in whom a corresponding tear was not found arthroscopically, meniscal tears at other sites or other abnormalities were correctly diagnosed using MR. A majority of the false-positive MR images involved the posterior horns of the menisci, the sites of most false-negative arthroscopic diagnoses. The predictive value of a negative MR image was almost 100%. Even in patients with moderate-to-large effusions, the menisci were accurately evaluated. The results imply that MR imaging is useful in the preoperative evaluation of suspected meniscal tears. 相似文献
80.
Percutaneous drainage access: a simplified coaxial technique 总被引:1,自引:0,他引:1
vanSonnenberg E; Wittich GR; Schiffman HR; Cabrera OA; Willson SA; Quinn SF; Casola G; Hayne LA; Polansky AD 《Radiology》1986,159(1):266-268
We describe an access technique that we have used in 150 nephrostomy and biliary drainage procedures and for access to some abscesses and viscera. The system provides safe coaxial access with a 22-gauge removable hub needle, which then acts as a guide wire and is replaced by an 18-gauge cannula. A major advantage is that only one guide wire is used (0.038-inch) for the entire drainage procedure. No significant complications have occurred to date with this method. 相似文献