Prospective subjective evaluation of swallowing function and dietary pattern in head and neck cancers treated with concomitant chemo-radiation

Aim : Prospective subjective evaluation of swallowing function and dietary pattern in locally advanced head and neck cancer patients treated with concomitant chemo-radiotherapy (CRT). Materials and Methods : Prospective evaluation of swallowing function with performance status scale for head and neck cancer patients (PSSHN) at pre-CRT, CRT completion and at subsequent follow-ups in adult with loco-regionally advanced head and neck squamous cell carcinoma (HNSCC) patients. Results : In 47 patients (40 male, seven females; mean age 53; 72% smoker 53%, oropharyngeal cancer), the mean total PSSHN score at pre-CRT was 258.5 and decreased to 225.2 and 219.2 at two and six months respectively. Understandability of speech, normalcy in diet and eating in public at pre-CRT and six months were 91.5 and 84.4; 80.4 and 63.1; 87.3 and 76.6 respectively. In univariate analysis, pre-CRT PSSHN scores were significantly lesser in patients with severe pre-CRT dysphagia (P = 0.001), hypopharyngeal cancer (P = 0.244) and advanced T-stage (T3/4) disease (P = 0.144). At CRT completion, there was significant reduction of PSSHN scores in patients with severe pre-CRT dysphagia (P = 0.008), post-CRT weight loss (>10%) and disease progression (P = 0.039). At two months and six months, 17 (57%) and 11 (73.5%) patients respectively showed change in dietary habit. Mean increase in meal time was 13% and 21% at two and six-month follow-up. Conclusions : HNSCC patients show deterioration in swallowing function after CRT with normalcy of diet in maximum and eating in public least affected. Pre-CRT severity of dysphagia, weight loss> 10% and disease progression have significant correlation with higher swallowing function deterioration after CRT

Radiation Induced Liver Toxicity

Liver was always considered to be ‘highly sensitive’ to radiation therapy (RT) and was not considered ‘safe’ for radiation therapy treatment. The most significant radiation induced liver toxicity was described by Ingold et al. as “Radiation hepatitis.” Historically, radiation to liver lesions with curative intent or incidental exposure during adjacent organ treatment or total body irradiation implied whole organ irradiation due to lack of high precision technology. Whole organ irradiation led to classic clinical picture termed as “Radiation Induced Liver Disease (RILD).” In conventional fractionation, the whole liver could be treated only to the doses of 30–35Gy safely, which mostly serves as palliation rather than cure. With the advent of technological advancements like IMRT, especially stereotactic radiation therapy (SBRT), the notion of highly precise and accurate treatment has been made practically possible. The toxicity profile for this kind of focused radiation was certainly different from that of whole organ irradiation. There have been attempts made to characterize the effects caused by the high precision radiation. Thus, the QUANTEC liver paper distinguished RILD to ‘classic’ and ‘non-classic’ types. Classic RILD is defined as ‘anicteric hepatomegaly and ascites’, and also can also have elevated alkaline phosphatase (more than twice the upper limit of normal or baseline value). This is the type of clinical picture encountered following irradiation of whole or greater part of the organ. Non-classic RILD is defined by elevated liver transaminases more than five times the upper limit of normal or a decline in liver function (measured by a worsening of Child-Pugh score by 2 or more), in the absence of classic RILD. In patients with baseline values more than five times the upper limit of normal, CTCAE Grade 4 levels are within 3 months after completion of RT. This is the type of RILD that is encountered typically after high-dose radiation to a smaller part of liver. It is commonly associated with infective etiology. Emami et al. reported the liver tolerance doses or TD 5/5 (5% complication rate in 5 years) as 50 Gy for one-third (33%) of the liver, 35 Gy for two-thirds (67%) of the liver, and 30 Gy for the whole liver (100%). Liver function (Child Pugh Score), infective etiology, performance status and co-morbidities influence the radiation induced toxicity. Lyman–Kutcher–Burman (LKB)-NTCP model was used to assess dose-volume risk of RILD. Lausch et al. at London Regional Cancer Program (LRCP), developed a logistic TCP model. Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) reported recommendations that mean normal liver dose should be 500 cc receiving <12 Gy. The concept of body surface area (BSA) and Basal Metabolic Index (BMI) guided estimation of optimal liver volume is required to estimate the liver volume need to be spared during SBRT treatment. Radiation induced liver injury is potentially hazardous complication. There is no definitive treatment and a proportion of patient may land up in gross decompensation. Usually supportive care, diuretics, albumin supplement, and vitamin K replacement may be useful. Better case selection will avert incidence of RILD. Precise imaging, contouring, planning and respecting normal tissue constraints are critical. Radiation delivery with motion management and image guidance will allow delivery of higher dose and spare normal liver and hence will improve response to treatment and reduce RILD

Magnetic field effect on exciplex luminescence in liquids

The effect of a magnetic field on the luminescence of unlinked as well as linked exciplex systems has been discussed. The magnetic field modulated luminescence. (&#916;&#966;/&#966;) is not only dictated by the hyperfine interaction in the radical ion pair, but also by the environment, such as viscosity and dielectric constant (&#949;) of the medium and presence of other molecules in the neighbourhood of the exciplex. A complex interplay between spin evolution, radical pair recombination and diffusion determine the magnitude and nature of the magnetic field effect (MFE). The dependence of (&#916;&#966;/&#966;) on the e could be explained on the basis of simple theoretical models. The concept of Heisenberg spin exchange has been invoked to rationalise the quenching of MFE by lanthanide ions. Time-resolved studies provide useful information regarding the dynamics of the spin-evolution of the system. In viscous medium the rotational diffusion slows down and the MFE becomes dependent on the direction of the field with respect to the exciplex

Magnetic field effect and multiplicity of conformation in a polymer-linked exciplex system

The magnetic field sensitivity of the pyrene-dimethylaniline (Py-DMA) system, linked by a polystrene (PS) spacer, was examined. It was found that isodielectric mixtures of tetrahydrofuran (THF) and dimethylformamide (DMF) and benzene and dimethylsulphoxide (DMSO) behave differently, the latter quenching the magnetic field effect more than the former; this is opposite to that found for the unlinked Py-DMA system. These studies demonstrate the importance of the solvent-dependent polymer backbone conformation. It was found that, in both of the above solvent mixture, the normal luminescence (&#966;) and the magnetic-field-modulated luminescence (&#948;&#966;) exhibit a shift in wavelength, indicating conformers with different magnetic sensitivities. The spectra taken at different times after excitation also support this conclusion

Detecting Danger: AI-Enabled Road Crack Detection for Autonomous Vehicles

The present article proposes the deep learning concept termed ―Faster-Region Convolutional Neural Network‖ (Faster-RCNN) technique to detect cracks on road for autonomous cars. Feature extraction, preprocessing, and classification techniques have been used in this study. Several types of image datasets, such as camera images, faster-RCNN laser images, and real-time images, have been considered. With the help of GPU (graphics processing unit), the input image is processed. Thus, the density of the road is measured and information regarding the classification of road cracks is acquired. This model aims to determine road crack precisely as compared to the existing techniques

Comparison of geometric uncertainties using electronic portal imaging device in focal three-dimensional conformal radiation therapy using different head supports

Aims and Objectives: To study the geometric uncertainties in the treatment and evaluate the adequacy of the margins employed for planning target volume (PTV) generation in the treatment of focal conformal radiotherapy (CRT) for patients with brain tumors treated with different head support systems. Materials and Methods: The study population included 11 patients with brain tumors who were to be treated with CRT. Contrast-enhanced planning CT scan (5-mm spacing and reconstructed to 2 mm) of brain were performed. Five patients were immobilized using neck support only (NR-only) and six patients had neck support with flexion (NRF), the form of immobilization being decided by the likely beam arrangements to be employed for that particular patient. The data was transferred to the planning system (CadPlan) where three-dimensional conformal radiation therapy was planned. Digitally reconstructed radiographs (DRRs) were created for the orthogonal portals with the fixed field sizes of 10 x 10 taken at the isocenter. Treatment verification was done using an amorphous silicon detector portal imaging device for using orthogonal portals and the DRR was used as a reference image. An image matching software was used to match the anatomical landmarks in the DRR and the portal imaging and the displacement of the portals in x, y axis and rotation were noted in the anteroposterior (AP) and lateral images. Electronic portal imaging was repeated twice weekly and an average of 8-14 images per patient was recorded. The mean deviation in all the directions was calculated for the each patient. Comparison of setup errors between the two head support systems was done. Results: A total 224 images were studied in anterior and lateral portals. The patient group with NR-only had 100 images, while the NRF group had 124 images. The mean total error in all patients, NR-only group, and NRF group was 0.33 mm, 0.24 mm, and 0.79 mm in the mediolateral (ML) direction; 1.16 mm, 0.14 mm, and 2.22 mm in the AP direction; and 0.67 mm, 0.31 mm, and 0.96 mm in the superoinferior (SI) direction, respectively. The systematic error (S) in all patients, NR-only group, and NRF group in the ML direction was 0.31 mm, 0.28 mm, and 0.78 mm; 1.29 mm, 0.1 mm, and 2.24 mm in the AP direction; and 0.75 mm, 0.52 mm, and 0.94 mm in the SI direction, respectively. Random error (s) in all patients, NR-only group, and NRF group in the ML direction was 1.25 mm, 1.04 mm, and 1.41 mm; 1.31 mm, 1.36 mm, and 1.28 mm in the AP direction; 1.38 mm, 1.37 mm, and 1.39 mm in the SI direction, respectively. In all patients, the PTV margin with Stroom′s formula in the NR-only and NRF group was 1.29 mm and 2.55 mm in the ML, 1.15 mm and 5.38 mm in the AP, and 2.0 mm and 2.85 mm in the SI directions, respectively. Conclusion: A PTV margin of 5 mm appears to be adequate; further reduction to 3 mm may be considered based on our results. Errors were significantly higher in the AP direction with NRF when compared to NR-only. Differential PTV margin may therefore be considered, with more margin in the AP and less in other directions, especially with the use of flexion devices

Magnetic field effect on the benzophenone-sodium dodecyl sulphate system: influence of external additives

Addition of small amphiphiles such as 1,4-dioxane is found to affect radical recombination and escape rates in micelles such as sodium dodecyl sulphate (SDS). This has been demonstrated with the hydrogen-abstracted product of triplet benzophenone as the probe molecule. This result has been interpreted on the basis of the ability of dioxane to form "mixed" micelles, which thereby affect the size, viscosity and reflectivity of the boundary of SDS. Studies in presence of magnetic fields up to 15 kG show that the magnetic field effect remains unaffected by the addition of dioxane. This his been explained as due to the combined effect of size, viscosity and reflectivity of the boundary of the micelle