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1.
Divya Prabhat S. K. Bhargava K. N. Dandekar S. B. Ogale 《Indian journal of otolaryngology and head and neck surgery》1993,45(1):31-32
Malignancies of the middle ear and mastoid are rare and secondaries in the ear are extremely rare. A rare case of metastic adenocarcinoma from the breast is presented herewith. 相似文献
2.
Carcinoma of the cervix is typically treated with a combination of intracavitary brachytherapy and external beam radiation. The external beam dose is delivered with whole pelvis fields followed by split fields that protect midline organs at risk (bladder and rectum) while treating the parametria. Three approaches have been developed to shield midline structures: a simple rectangular block, a block customized to a single brachytherapy isodose line, and a step wedge filter constructed to conform to multiple brachytherapy isodose lines. A customized step wedge filter has the potential to produce a more homogeneous dose distribution but has not achieved widespread use due to labor intensive construction. We have developed a simple, novel method to produce a custom midline step wedge using dynamic multileaf collimation (dMLC). A comparison of film measurements in a phantom with the dose calculated by a commercial treatment planning system demonstrated agreement within 3% or 3 mm. The technique requires delivery times comparable to conventional techniques. 相似文献
3.
Unlike the penetrating monoenergetic 662 keV gamma rays emitted by 137Cs LDR sources, the spectrum of 192Ir used in HDR brachytherapy contains low-energy components. Since these are selectively absorbed by the high-atomic number materials of which intracavitary applicators are made, the traditional neglect of applicator attenuation can lead to appreciable dose errors. We investigated the attenuation effects of a uterine applicator, and of a set of commonly used vaginal cylinders. The uterine applicator consists of a stainless steel source guide tube with a wall thickness of 0.5 mm and a density of 8.02 g/cm3, whereas the vaginal cylinders consist of the same stainless steel tube plus concentric polysulfone cylinders with a radius of 1 or 2 cm and a density of 1.40 g/cm3. Monte Carlo simulations were performed to compute dose distributions for a bare 192Ir-HDR source, and for the same source located within the applicators. Relative measurements of applicator attenuation using ion-chambers (0.125 cm3) confirmed the Monte Carlo results within 0.5%. We found that the neglect of the applicator attenuation overestimates the dose along the transverse plane by up to 3.5%. At oblique angles, the longer photon path within applicators worsens the error. We defined attenuation-corrected radial dose and anisotropy functions, and applied them to a treatment having multiple dwell positions inside a vaginal cylinder. 相似文献
4.
Sangeeta Varty Dinesh Vaidya Kamal Parasram Divya Prabhat Sudhir Joshi 《Indian journal of otolaryngology and head and neck surgery》2000,52(2):143-146
Tuberculosis of the middle ear it a rare disease. Due to change in the typical clinical pattern and decrease in incidence,
there is a delayed or missed diagnosis and can lead to increased morbidity. We pretent 5 cases of Tuberculous Otitis Media
treated over a period of 2 years, highlighting the fact that it must be considered as a differential diagnosis of persistent
suppurative otitis media. 相似文献
5.
Divya S. Parimi Yamini Gupta Sreekar Marpu Chandra S. Bhatt Tharun K. Bollu Anil K. Suresh 《Journal of Pharmaceutical Analysis》2022,12(3):365-379
Cancer therapy is a fast-emerging biomedical paradigm that elevates the diagnostic and therapeutic potential of a nanovector for identification, monitoring, targeting, and post-treatment response analysis. Nanovectors of superparamagnetic iron oxide nanoparticles (SPION) are of tremendous significance in cancer therapy because of their inherited high surface area, high reactivity, biocompatibility, superior contrast, and magnetic and photo-inducibility properties. In addition to a brief introduction, we summarize various progressive aspects of nanomagnets pertaining to their production with an emphasis on sustainable biomimetic approaches. Post-synthesis particulate and surface alterations in terms of pharmaco-affinity, liquid accessibility, and biocompatibility to facilitate cancer therapy are highlighted. SPION parameters including particle contrast, core-fusions, surface area, reactivity, photosensitivity, photodynamics, and photothermal properties, which facilitate diverse cancer diagnostics, are discussed. We also elaborate on the concept of magnetism to selectively focus chemotherapeutics on tumors, cell sorting, purification of bioentities, and elimination of toxins. Finally, while addressing the toxicity of nanomaterials, the advent of ultrasmall nanomagnets as a healthier alternative with superior properties and compatible cellular interactions is reviewed. In summary, these discussions spotlight the versatility and integration of multi-tasking nanomagnets and ultrasmall nanomagnets for diverse cancer theragnostics. 相似文献
6.
An essential part of the teaching-learning paradigm is assessment. It is one of the ways to achieve feedback for the various methods that have been used to impart a particular skill. This is true of ophthalmology training, where various clinical and surgical skills are learned as part of the residency program. In preparation for residents to become proficient ophthalmologists, both formative and summative assessments are of paramount importance. At present, assessment is primarily summative in the form of a university examination, including theory and practical examinations that are conducted at the end of the three years of residency. A formative assessment can make course corrections early on, allowing for an improved understanding of the subject and the acquisition of clinical and surgical skills. Formative assessments also allow us to customize the teaching methodology considering individual residents’ learning capabilities. In addition, formative assessments have the advantage of alleviating the stress of a “final” examination, which could sometimes result in a less-than-optimum performance by the residents. The COVID-19 pandemic has forced us to adopt new teaching methods, which has led to the adoption of changes in assessment. In this regard, we discuss the different assessment tools available, their pros and cons, and how best these tools can be made applicable in the setting of an ophthalmology residency program. 相似文献
7.
Lileswar Kaman Syed Nusrath Divya Dahiya Ajay Duseja Sameer Vyas Vikas Saini 《Updates in surgery》2012,64(4):257-264
Pancreatic fistula is a major cause of morbidity and mortality after pancreaticoduodenectomy. External drainage of pancreaticojejunostomy anastomosis with a stent is used to reduce the rate of pancreatic fistula. This study compares the rates of pancreatic fistula between external stent drainage versus no-stent drainage for pancreaticojejunal anastomosis following pancreaticoduodenectomy. A total of 53 patients undergoing pancreaticoduodenectomy for various benign and malignant pathologies were included in the study. An external stent was inserted across the anastomosis to drain the pancreatic duct in 26 patients and 27 patients received no stent. The primary end point was pancreatic fistula. All surgeries were done by a single surgeon with expertise in hepatobiliary pancreatic surgery at a single institute. The two groups were comparable in demographic data, underlying pathologies, presenting complaints, presence of comorbid illnesses and proportion of patients with preoperative biliary drainage, pancreatic consistency and duct diameter. The pancreatic fistula rates were similar in both the groups (11.5 vs. 14.8?%, P?=?0.725). The morbidity and surgical re-exploration rate were statistically not significant between the two groups (65.4 vs. 51.9?%, P?=?0.318 and 11.5 vs. 7.4?%, P?=?0.60). Postoperative stay was also similar with a mean of 14?days in both the groups (P?=?0.66). The mortality rate was statistically not significant in the two groups (3.8 vs. 7.4?%, P?=?0.575). External drainage of pancreaticojejunostomy anastomosis and the pancreatic duct with a stent does not decrease the rate of postoperative pancreatic fistula after pancreaticoduodenectomy. 相似文献
8.
Hounsfield units on computerized tomography predict stone-free rates after extracorporeal shock wave lithotripsy 总被引:6,自引:0,他引:6
PURPOSE: Studies suggest that HU values on non-contrast computerized tomography may predict the ability to fragment urinary calculi. We determined whether the HUs of in vivo urinary stones could be used to predict the stone-free rates after extracorporeal shock wave lithotripsy. MATERIALS AND METHODS: We evaluated 50 patients who underwent extracorporeal shock wave lithotripsy for 5 to 10 mm. upper urinary tract stones. Chemical analyses and HU calculations were performed for each stone and posttreatment radiographic assessment categorized patients into a stone-free or a residual stone group. Statistical analysis was performed using the Student t test to compare mean HU values in the 2 groups. RESULTS: Of the patients 32 (64%) were stone-free and 18 (36%) had residual stones. Mean values +/- SEM for the stone-free and residual stone groups were significantly different (551.20 +/- 46.66 versus 926.20 +/- 51.42 HU, p <0.0001). A total of 30 calculi (60%) were located in the ureter, including 21 in the stone-free group and 9 in the residual stone group with a mean value of 505.10 +/- 46.66 and 888.70 +/- 102.00 HU, respectively, which was significantly different (p = 0.0005). A total of 20 calculi (40%) were located in the kidney, including 11 in the stone-free group and 9 in the residual stone group with a mean value of 558.40 +/- 62.38 and 905.10 +/- 61.49 HU, respectively, which was significantly different (p = 0.001). CONCLUSIONS: These findings suggest that HU measurement of urinary calculi on pretreatment non-contrast computerized tomography may predict the stone-free rate. This information may be beneficial for selecting the preferred treatment option for patients with urinary calculi. 相似文献
9.
10.