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121.
Alfons C.M. van den Bergh Jan PruimThera P. Links Anton M. van der VlietWim Sluiter Bruce H.R. WolffenbuttelJohannes A. Langendijk Eelco W. HovingRobin P.F. Dullaart 《Radiotherapy and oncology》2011,98(2):213-216
Introduction
Positron emission tomography (PET) using amino acid tracers is able to establish biochemical tumour characterization in vivo. The use of PET in the follow-up of non-functioning pituitary adenomas (NFA) and growth hormone producing pituitary adenomas (GHA) after surgery and radiation treatment is not yet clear.Methods
To determine the value of PET before and after transsphenoidal neurosurgery in NFA and GHA, we investigated 12 patients with pituitary adenoma (9 NFA and 3 GHA) before and 4 months after surgery with magnetic resonance imaging (MRI) and tyrosine PET (TYR-PET). Three years after radiation therapy TYR-PET was used to document residual activity in 6 of these patients (4 NFA- and 2 GHA). Tumour size was quantified by computerized MRI measurements. In TYR-PET, tumour activity was assessed by computerized measurements of the hot spot and by determination of protein synthesis rate (PSR).Results
In response to surgery, MRI showed a median tumour volume reduction of 58% (P < 0.01). TYR-PET demonstrated 62% volume reduction (P < 0.02), but no change in PSR (P > 0.30). After radiation therapy the MRI-volumes of the residual pituitary adenomas did not change but the volume of the hot spot on TYR-PET-imaging was reduced by 58% (P = 0.02), and PSR decreased in 5 of 6 patients (P = 0.12).Conclusion
Amino acid PET tumour activity is reduced parallel with MRI volume changes after surgery. The decrease in TYR-PET activity after radiation therapy, despite unaltered MRI tumour volume, supports the concept that it is possible to follow biological tumour activity with this technique. The diagnostic merit of this tracer technique, predicting pituitary adenoma re-growth, needs to be validated in a large prospective study. 相似文献122.
123.
VS Gurunadh A Banarji S Patyal AK Upadhyay TS Ahluwalia RP Gupta M Bhaduria 《Medical Journal Armed Forces India》2010,66(2):125-128
Background
Vitreous substitutes presently in use for intraoperative tamponade are perfluorocarbon liquids (PFCL) and for post operative tamponade are silicon oil (SO), sulphur hexafluoride (SF6) and perfluorocarbon gas (PFC). Several factors are important for a thorough understanding of each of these vitreous substitutes. The absorption or necessity for removal, indications for use (including clinical studies and special surgical methods), additives and complications of use have to be considered.Methods
Three port standard pars plana vitrectomy was performed in 60 consecutive cases requiring intra-vitreal intervention. PFCL was used intra-operatively in 30 cases (PFCL group and X group). The eyes were implanted with SO (silicon oil subgroup), PFC (C3F8 sub-group) and SF6 (SF6 sub-group) in twenty cases each. Apart from best corrected visual acuity (BCVA), the retinal status and the longevity of gas when used, changes and reaction in both the anterior and posterior segments were noted.Result
The difference of postoperative BCVA in the PFCL and non-PFCL groups was statistically significant with p < 0.001. In both the PFCL and non-PFCL groups the difference between preoperative and postoperative BCVA was statistically significant with p < 0.0001. All three vitreous substitutes studied are effective given the case where they had been utilised.Conclusion
PFCL is invaluable in the management of complicated retinal detachment (RD). Where a vitreous microsurgery is indicated, the visual outcome is good. SF6 is useful for short-term tamponade. Silicon oil and C3F8 are useful for longer tamponade.Key Words: Tamponade, Perfluorocarbon liquids, Silicon oil, Sulphur hexafluoride, Perfluorocarbon gas, Retinal detachment 相似文献124.
125.
126.
Karin Eijkelenkamp Thamara E. Osinga Mirjam M. de Jong Wim J. Sluiter Robin P. F. Dullaart Thera P. Links Michiel N. Kerstens Anouk N. A. van der Horst-Schrivers 《Familial cancer》2017,16(1):123-130
Germline mutations of the gene encoding succinate dehydrogenase subunit B (SDHB) predispose to head-and-neck-paraganglioma (HNPGL), sympathetic PGL, pheochromocytoma and renal cell carcinoma for which regular surveillance is required. SDHB-associated tumors harbor germline and somatic mutations, consistent with Knudson’s two-hit hypothesis. To assess the penetrance and optimal surveillance for different manifestations of SDHB mutation carriers. This study included all SDHB mutation carriers who were followed at the Department of Endocrinology at the University Medical Center of Groningen. Kaplan–Meier curves were used to assess the penetrance. Poisson process was used to assess the optimal age to start surveillance and intervals. Ninety-one SDHB-mutation carriers (38 men and 53 women) were included. Twenty-seven mutation carriers (30 %) had manifestations, with an overall penetrance 35 % at the age of 60 years. We calculated that optimal surveillance for HNPGL could start from an age of 27 years with an interval of 3.2 years. This study underscores the relatively low penetrance of disease in SDHB mutation carriers. Use of the Poisson approach provides a more accurate estimation of the age to initiate surveillance and length of intervals for HNPGL. These results may give rise to reconsider the current guidelines regarding the screening of these mutation carriers. 相似文献
127.
128.
O Al‐Saeed M Ismail RP Athyal M Rudwan S Khafajee 《Journal of Medical Imaging and Radiation Oncology》2009,53(4):366-372
T1‐weighted fluid‐attenuated inversion recovery (FLAIR) sequence is a relatively new pulse sequence for intracranial MR imaging. This study was performed to compare the image quality of T1‐weighted FLAIR with the T1‐weighted FSE sequence. Twenty patients with brain lesions underwent T1‐weighted fast spin‐echo (FSE) and T1‐weighted FLAIR during the same imaging session. Four quantitative and three qualitative criteria were used to compare the two sequences after contrast. Two of four quantitative criteria pertained to lesion characteristics: lesion to white matter (WM) contrast‐to‐noise ratio (CNR) and lesion to cerebrospinal fluid (CSF) CNR, and two related to signals from normal tissue: grey matter to WM CNR and WM to CSF CNR. The three qualitative criteria were conspicuousness of the lesion, the presence of image artefacts and the overall image contrast. Both T1‐weighted FSE and FLAIR images were effective in demonstrating lesions. Image contrast was superior in T1‐weighted FLAIR images with significantly improved grey matter‐WM CNRs and CSF‐WM CNRs. The overall image contrast was judged to be superior on T1‐weighted FLAIR images compared with T1‐weighted FSE images by all neuroradiologists. Two of three reviewers considered that the FLAIR images had slightly increased imaging artefacts that, however, did not interfere with image interpretation. T1‐weighted FLAIR imaging provides improved lesion‐to‐background and grey to WM contrast‐to‐noise ratios. Superior conspicuity of lesions and overall image contrast is obtained in comparable acquisition times. These indicate an important role for T1‐weighted FLAIR in intracranial imaging and highlight its advantage over the more widely practiced T1‐weighted FSE sequence. 相似文献
129.
敏定偶用于35岁以上妇女的疗效、安全性和周期控制 总被引:11,自引:0,他引:11
<正> 口服避孕药在投放市场之初,应用于各种年龄段的妇女。然而资料显示早期使用的高剂量口服避孕药会增加心肌梗塞的发病率;在1975年,美国食品药物管理局(FDA)不建议40岁以上的妇女服用避孕药,对30岁以上的吸烟妇女建议她们要么停止吸烟要么改换避孕方式。随着研究的进一步深入及低剂量口服避孕药的问市,已证实任何年龄的非吸烟 相似文献