SU-E-T-649: Evaluation of RapidArc- Based Stereotactic Cranial Radiotherapy Plans with MU Objective Using Multiple Non Coplanar Arcs in Comparison with Conventional Dynamic Conformal Arc Technique

PURPOSE

Previous researches reported that RapidArc plans for stereotactic cranial radiotherapy have two to three times more MUs as compared to Conventional Dynamic Conformal Arc (DCA) Technique. This study aims to evaluate RapidArc plans using multiple non- coplanar arcs, developed with MU objective constraint in the optimization stage.

METHODS

Five single brain metastasis and three multiple metastases cases previously planned using DCA techniques in BrainLab iPlan Version 4.1 were investigated in this study. For each case, the target was defined on CT-MR fused images in iPlan. The CT images and contours of these patients were exported from iPlan to Varian Eclipse TPS Version 8.6. For each case, a DCA plan and a RapidArc plan with multiple non-coplanar arcs with and without using MU objective in the optimization stage were generated using Varian Trilogy machine with Millennium 120 MLC keeping the same prescription and critical structure dose limits. All plans were evaluated according to Conformity Index (CI-modified Paddick) Homogeneity Index (HI), and the normal tissue volume receiving various dose levels (V80%, V50%, V25% and V10%).

RESULTS

In all the plans, the target objectives were met and dose to OARs was within tolerance dose constraints. RapidArc plans with and without MU objective showed better CI and HI as supposed to DCA plans. V80%, V50%, V25% and V10% of normal tissue for RapidArc plans are equal or lesser than DCA plans. Single isocentre RapidArc plan for closely spaced multiple metastases cases showed better dose fall off between the lesions as supposed to DCA plans. RapidArc plans with MU objective resulted in comparable MUs as that of DCA plans.

CONCLUSIONS

Our study showed RapidArc plans done with and without MU objective have no significant dosimetric difference in plan objectives. Therefore, multiple non-coplanar RapidArc plans with MU objective is clinically feasible and can provide better treatment plans than conventional DCA plans, especially for complicated cases.

The early radiological results of the uncemented Oxford medial compartment knee replacement

We carried out a prospective investigation into the radiological outcomes of uncemented Oxford medial compartment unicondylar replacement in 220 consecutive patients (231 knees) performed in a single centre with a minimum two-year follow-up. The functional outcomes using the mean Oxford knee score and the mean high-activity arthroplasty score were significantly improved over the pre-operative scores (p < 0.001). There were 196 patients with a two-year radiological examination performed under fluoroscopic guidance, aiming to provide images acceptable for analysis of the bone–implant interface. Of the six tibial zones examined on each knee on the anteroposterior radiograph, only three had a partial radiolucent line. All were in the medial aspect of the tibial base plate (zone 1) and all measured < 1 mm. All of these patients were asymptomatic. There were no radiolucent lines seen around the femoral component or on the lateral view. There was one revision for loosening at one year due to initial inadequate seating of the tibial component. These results confirm that the early uncemented Oxford medial unicompartmental compartmental knee replacements were reliable and the incidence of radiolucent lines was significantly decreased compared with the reported results of cemented versions of this implant. These independent results confirm those of the designing centre.

Antioxidant activity and toxicity profile of total triterpenes isolated from Ganoderma lucidum (Fr.) P. Karst occurring in South India

The total triterpene fraction isolated from Ganoderma lucidum, a highly nutritional and popular medicinal mushroom occurring in South India, was evaluated for its antioxidant activity in vitro and in vivo. Total triterpenes successfully scavenged DPPH(+), ABTS(+) and superoxide radicals, showed significant ferric reducing activity and was highly effective in reducing the in vitro lipid peroxidation. Activities of the antioxidant enzymes in blood and tissue were increased by the administration of total triterpenes to Swiss albino mice in vivo. The ability of total triterpenes to scavenge the free radicals and to enhance body's antioxidant defence systems indicates its potential use as an antioxidant. An attempt was also done to gauge the toxicity of total triterpenes using acute and sub acute study models in Swiss albino mice. The results showed that Ganoderma triterpenes did not possess significant toxicity. The findings thus reveal the possible therapeutic use of Ganoderma triterpenes.

Molecular characterization of MHC class II region in guinea fowl

1. The MHC class II gene was amplified, cloned and sequenced in guinea fowl. 2. The NumeMHC II sequence of 754 nucleotides included complete exon 1 (91 nt), exon 2 (270 nt), exon 3 (282 nt) and exon 4 (110 nt). 3. The size of β(1) and β(2), domains were 89 and 93 amino acids, respectively in guinea fowl. 4. High amino acid variability (38·2%) was observed within guinea fowl in β(1) domain, while in β(2) domain, amino acid variability (6·3%) was low. 5. Among poultry species, the percent amino acid identity between guinea fowl and chicken, quail, pheasant and duck was 38·8, 42·2, 44·4 and 58·8 in β(1) domain; and 13·8, 17·0, 13·8 and 27·6 in β(2) domain, respectively. 6. Sequence alignment with mammalian and avian MHC showed that many of the conserved features of MHC class II glycoprotein was conserved in guinea fowl. 7. Within-species genetic distances (Poisson correction) based on cumulative amino acid variability in β(1) domain and β(2) domains was 0·141 in guinea fowl. 8. Guinea fowl showed low and similar genetic distances with all the poultry species (0·255-0·268) except duck (0·456). 9. Guinea fowl made separate branch within the major cluster having chicken, quail and pheasant, showing equal distance from these poultry species, whereas duck MHC II clustered separately.

Coccidioidomycosis in India: Report of a third imported case

We describe the third fatal case of imported coccidioidomycosis in India in a 31-year-old mechanical engineer originally from Andhra Pradesh, India, who lived in Gwinner, North Dakota. He had traveled to Arizona in summer of 2006, where he drove tractors in a dusty environment at a tractor production facility near Phoenix, Arizona. He was human immunodeficiency virus (HIV) positive. Initially, he was treated in Fargo, North Dakota, in 2006, with liposomal amphotericin B followed by oral fluconazole. Antiretroviral treatment for HIV infection was started. He moved back to India and was admitted to the intensive care unit of St. John's Medical College and Hospital, Bangalore, India. His blood cultures yielded Coccidioides sp. The identity of the isolate was confirmed using the Gen Probe Accuprobe test at the Centers for Disease Control and Prevention, Atlanta, Georgia. In spite of initiation of treatment with antifungal agents (amphotericin B and fluconazole), his condition deteriorated and he expired three days following his admission to the hospital.

Esophageal adenocarcinoma after laparoscopic gastric band placement for obesity

Obesity is a risk factor for the development of esophageal malignancy. We report a case of the development of esophageal adenocarcinoma after placement of an adjustable gastric band for obesity. A 66-year-old male was referred to our clinic for findings of an obstructing mass at the gastroesophageal junction after previously undergoing a laparoscopic adjustable gastric band placement. Investigations confirmed a locally advanced poorly differentiated esophageal adenocarcinoma. The patient underwent chemotherapy and gastric band removal with improvement of his dysphagia. However, his disease progressed and he died of metastatic disease. We discuss the diagnosis of esophageal carcinoma after gastric banding procedure.

Amputation and disability following snakebite in Nigeria

Snakebite is an important cause of amputation and disability in rural communities throughout the tropics. However, the details of the causes, types and estimates of disability are lacking. This report describes 16 snakebite victims who had amputations, including two who had above-knee amputations. The patients presented with limb swelling (16), gangrene (15), ischaemia (4) and three had possible compartment syndrome. All the patients used ineffective time wasting remedies that were potentially harmful as first-aid. The median delay to hospital following bite was 2.5 days. In order to prevent disability, efforts should be made to: reduce delay before hospital presentation; improve the knowledge of first-aid; provide effective antivenoms; improve wound and clinical care in communities; and improve facilities.

Klinefelter syndrome with systemic lupus erythematosus in an Indian man

Previously, cases of systemic lupus erythematosus (SLE) and Klinefelter syndrome (KS) in men have been reported in Western populations. We report the case of a 30-year-old man from southern India with known infertility who was diagnosed to have SLE and KS by fluorescence in-situ hybridization, as routine karyotype cultures failed. The diagnosis has implications in management and highlights the need for strong clinical suspicion and laboratory confirmation of KS by molecular methods when suspected in all men with SLE. Quicker, long-term remission and genetic counseling of such individuals can help in better management and coping with this chronic, potentially fatal disease. Lupus (2010) 19, 870-871.