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Introduction: Since 1980s, computerization has made improvements in radiation therapy delivery from conventional two-dimensional to three-dimensional conformal radiotherapy (2DCRT to 3DCRT) to intensity-modulated radiotherapy (IMRT) and its newer versions. This small study is aimed to compare the existing techniques for planning target volume (PTV) and organ at risk (OAR) dose distribution parameters in postoperative buccal mucosa cases. Materials and Methods: Ten post operative cases of early stage carcinoma buccal mucosa in whom only post operative bed irradiation was indicated was enrolled and was planned with conventional, 3DCRT and IMRT techniques to get 95% PTV coverage and dose received by organs at risk were recorded and evaluated. Results: Mean and standard deviation values for PTV 95% for IMRT, 3DCRT, and conventional plans were 96.4 ± 1.8, 95.1 ± 1.9, and 91 ± 2.7, respectively. Dose received by OARs was high in conventional technique when compared to the other two. Maximum dose received by 1 cc of brain (46.2 ± 7.9 and 60.8 ± 3.8) (priority was given for PTV coverage) and mean dose received by the same eye (13.6 ± 1.4 and 22 ± 2.4) were less in IMRT when compared to 3DCRT. However, maximum dose received by 1 cc of brainstem (29.7 ± 7.6 and 14.1 ± 9.5), optic chiasma (29.2 ± 4.2 and 12 ± 2.1), spinal cord (31.8 ± 3 and 20.9 ± 4.2), and the same-side optic nerve (22 ± 6.9 and 11.7 ± 9.4) and mean dose received by opposite-side parotid (8.7 ± 1.1 and 1.7 ± 0.4) and submandibular gland (18.6 ± 1.7 and 3.2 ± 0.9) were more with IMRT when compared to 3DCRT. Conclusion: In postoperative cases of early-stage carcinoma buccal mucosa, it is good enough to treat with 3DCRT technique. Here, the target area will be well lateralized, and 3DCRT technique can give good target coverage and less dose to OARs, especially the only remaining major salivary glands.
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Introduction: Anterior cerebral artery (ACA), the smaller terminal branch of the internal carotid artery is significantclinically due to its wide variety of complexity and technical difficulty in surgical procedures.Methods and materials: This study was done in 50 embalmed adult brain hemispheres at Institute of Anatomy,Madras Medical College, Tamilnadu. The study of the anterior cerebral artery was undertaken to observe themode of origin, its course and branches.Results: Anterior cerebral artery originated from the internal carotid artery in 100% of specimens. ACA passedabove optic nerve in 32 specimens (64%), above optic chiasma in 16 specimens (32%) and above optic tract in 2specimens (4%). The average length of A1 segment of right ACA and left ACA were 14.3 mm and 13.7 mm respectively.The difference in diameter of 1mm or more on both sides was observed in 8%. Left A1 segment was duplicated in1 specimen (2%). Median artery of corpus callosum and Azygous anterior cerebral artery were found in onespecimen each. Fenestration of A2 segment was observed in one specimen (4%). Heubner’s artery arose from A2segment in 32 (64%) specimens, from A1 segment in 6 (12%) specimens and from the level of ACoA in 12 (24%)specimens. The orbitofrontal artery originated on an average distance of 5.73mm on right side and average of4.82mm on left side. Frontopolar artery(FPA) originated at a distance of about 20.2mm on right side and 17.6mmon left side. Callosomarginal artery and pericallosal artery were found in all the specimens. In one specimen theright FPA originated from callosomarginal artery.Conclusion: Rapidly advancing fields of vascular neurosurgery and interventional neuroradiology techniquesrequire a thorough understanding of the anatomy. This detailed study done under various parameters wouldbenefit the radiologists and neurosurgeons.
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Objectives: The objective of the present study is to evaluate the bond strength of: (a) Zirconia blocks (tribochemical treatment and zirconia primer) and resin blocks bonded using self-adhesive resin cement (phosphate monomer cement). (b) Zirconia blocks and resin blocks bonded using nonphosphate monomer cement. (c) Micro-tensile bond strength of zirconia and resin blocks, bonded with self-adhesive resin cement and nonphosphate monomer cement after thermocycling. Materials and Methods: Twenty zirconium-dioxide specimens (5 mm × 5.4 mm × 13 mm) were produced using a metal mold. Each zirconium block was duplicated in light-curing resin material specimen (5 mm × 5.4 mm × 13 mm) using a mold made of addition silicon impression material. A total of 40 specimens were made, of which 20 specimens were zirconia blocks and 20 were resin blocks, which would be bonded to each other using phosphate monomer-containing cement (Multilink [10 nos.]) and nonphosphate monomer-containing cement (RELY-X [10 nos.]). The specimens were then divided into two groups of n = 10 each. The surface of zirconium specimen of one group (Group 1) was treated with zirconia primer and bonded with phosphate monomer-containing cement, and the other groups (Group 2) were not treated with any surface conditioning and were bonded with a nonphosphate containing cement. The specimens in each group were further subdivided into two subgroups of n = 5 each as follows: Group 1-1A (subjected to thermocycling), 1B (nonthermocycled) and Group 2-2A (subjected to thermocycling), 2B (nonthermocycled). Then, they were subjected for testing of tensile bond strength under a universal testing machine. Results: Resin cement selection seems to be a more relevant factor in the bonding of zirconia. The phosphate monomer-containing cement has the better bond strength after thermocycling compared to the nonphosphate monomer group. Thermocycling reduced the bond strength of both the groups and a significant difference was seen in the bond strength of nonphosphate monomer cement group subjected to thermocycling compared to the nonthermocycled one. Tensile bond strength values were significantly affected by the luting agent system employed and by thermal aging. Hence, for long-term durability, luting of zirconia with a phosphate monomer-containing cement after the zirconia has been surface treated is preferable as their bond strength did not show much significant difference after being subjected to thermocycling, compared to the nonthermocycled group. Conclusion: Resin cement selection seem to be a more relevent factor in the bonding of zirconia thermocycling does affect adhesion to to zirconium oxide ceramics.
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Background: Febrile thrombocytopenia due to various etiologies is very common in India. Its clinical manifestations range from asymptomatic infections to severe disease. Cardiac involvement in such systemic illness should be evaluated. Aim of present study is to evaluate cardiac involvement in patients with Febrile thrombocytopenia with platelets count less than 50,000/µL with the help of handheld echocardiography.Methods: Two hundred patients who had fever with thrombocytopenia were enrolled in the study. ECG and echocardiogram were done to all the patients. One-way ANOVA, Chi square test and correlation coefficient from Pearson correlation and P value of < 0.05 was taken as significant.Results: Out of 200 patients there were 146 males and 56 females. The mean age was 24.12yrs in males 28.32yrs in females .Rhythm abnormalities were present in 60 patients and the most common abnormality was sinus tachycardia; 17 patients had ascites and right pleural effusion; 24 patients presented with pericardial effusion and incidental diagnosis of CHD, RHD, and CAD were made; two patients had myocarditis as evidenced by global hypokinesia of left ventricle. All of those cardiac manifestations were common in Dengue Shock Syndrome.Conclusions: Cardiovascular manifestation in Febrile thrombocytopenia is relatively common ranging from pericarditis to myocarditis. Clinician should routinely screen patients with pyrexia with thrombocytopenia for cardiac manifestations. Early diagnosis at bed side may improve the outcome. Management of patients with pre-existing cardiac diseases should be individualized.
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Seawater intrusion is a major problem in urbanized coastal regions of India which is due to over exploitation of groundwater for various purposes. This study was carried out with the objective of assessing the zone of mixing between seawater and groundwater in the coastal aquifer in south of Chennai, Tamil Nadu, India using high resolution electrical resistivity tomography. High resolution electrical resistivity tomography was carried out in five profiles perpendicular to the sea using IRIS make SYSCAL Pro-96 system with 2.5 m or 5 m inter-electrode separation. The maximum length of the profile was 170 m which resulted in a depth of investigation of 28.7 m. The apparent resistivity measured in this area varies from 0.3 ohm-m to 30,000 ohm-m. The apparent resistivity of saturated zone decreases towards the sea, indicating the influence of seawater. This was also confirmed by measuring the electrical conductivity of groundwater, which gradually increases from 156 micro S/cm to 3430 micro S/cm towards the sea. Further, the concentration profiles of electrical conductivity, sodium, chloride and chloride / bicarbonate ratio are compared with the high resolution electrical resistivity tomography profile. The distance of influence of seawater is comparatively high in northern part than in southern part of the area. The high resolution electrical resistivity tomography was effectively used to determine the effect of seawater mixing with groundwater