IMRT patients but remained within the dose TD 5/5 and Quantec constraints6. For the contralateral parotid, the mean dose for the IMRT was 1707 cGy compared to the wedged pair dose of 294cGy. The Quantec mean dose for unilateral parotid is 2000cGy and the TD 5/5 is 3200 cGy. Both are within limits to prevent xerostomia. The submandibular is another area that can cause dry mouth if the dose is over the TD 5/5 of 3900 cGy. For the IMRT the mean dose for the contralateral submandibular was 1788 cGy and for the wedged pair 444 cGy. So again, the dose is within the constraint for complicated side effects. The contralateral parotid and submandibular are important to prevent xerostomia and improve quality of life. Curative patients have long …show more content…
The mean PTV of the IMRT plan 6347 cGy and the wedge pair mean is 6414 cGy. The total mean dose that is trying to be achieved is 6167 cGy. The PTV had a sharper dose fall off to the PTV after the prescription dose was achieved than the wedged pair did. Discussion By just looking at the mean dose of the OAR, the wedge pair is a better option in planning. However, after evaluating the DVH and isodose distribution, the assessment becomes more complex. The conformality of IMRT is much better planning method to navigate the complex contour of the neck and the OARs that must have dose constraints to reduce side effect and increase quality. In the head and neck region, there are other considerations for dose constraint and accurate treatment of the tumor volume. Anatomical and set-up error can cause an increased dose of OARs and reduced tumor dose9. Changes in anatomy over the over the course of treatment such as tumor and lymph node shrinkage and weight loss can change the dosimetry.9 This is important in planning. With IMRT, daily imaging is often incorporated and includes IGRT. IGRT method can reduce the error in set-up and help to treat the tumor volume more accurately. Another methods treatment to consider is proton therapy. A pencil beam proton therapy can guide the beam to cover the PTV. There is a sharp fall off with proton therapy which makes it possible for the target volume to be covered and the OARs to give little or no dose.
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Although the types of toxicities are comparable to prior research, there has been minimal data reported regarding the specific nature and severity of these toxicities experienced during XRT. In the current study, maximal incidence of Grade 2 severity across the toxicities monitored in this study ranged from 12-68%. This data supports that XRT induced toxicities in this clinical group were mostly mild and the majority of the patients did not require SLP intervention to manage symptoms, including dysphagia, while undergoing treatment. The low level of severe toxicities experienced by patients in our current study was similar to that found in the few studies to date which examined early toxicities following PGC management. Oliver et al. (2004) found that only 23% of their study population of 25 patients who underwent XRT experienced Grade 2 mucositis, which is directly comparable to the incidence of oral mucositis (24%) and pharyngeal mucositis (28%) in the current cohort. In comparison, Chung et al. (2011) and Patel et al. (2014) reported only 3-5% of their study population experienced Grade 2 mucositis. Chung et al. also reported low incidence of Grade 2 xerostomia (5%), while Patel et al. reported only Grade 1 xerostomia and dysgeusia in 5%. These maximal incidence rates for early toxicities are much lower than the current study data. However different rating scales (Radiation Therapy Oncology Group
The total challenge dose is calculated as 0.15 to 0.3 g protein/kg body weight, not to exceed 3 g protein or 10 g whole food. In patients with a previous history of severe reactions, a lower starting dose of 0.06 g protein/ kg body weight is recommended. If the patient remains asymptomatic for 4 hours, a second dose is given, generally an appropriate single-serving amount followed by 2 to 3 hours of
99mTc-sestamibi is used as a radiotracer, but it is not truly specific to parathyroid tissue; it also accumulates in salivary, thyroid, and cardiac tissues. For intraoperative gamma detection, patients are injected intravenously with a low dose of 10 mCi 99mTc-sestamibi approximately 1 to 2 hours before operation. For patients who have previously
The author of this article talks about the use of SPECT/CT in many different ways relating to thyroid cancer staging and assessment of risk. Some of these areas include “problem solving, diagnostic preablation, and lesional dosimetry” (Avram, 2014 pp175, 177). Avarm starts with the advantages of using SPECT/CT in association with diagnosis and treatment of thyroid cancer. The first and major advantage of using SPECT/CT discussed by Avarm is “accurate anatomic localization and characterization of radioiodine foci as benign or malignant” (Avram, 2014 pp172). The author explains how this is such as huge advantage over planar imaging because it allows for a more accurate diagnosis. A study the author references shows “SPECT/CT accurately characterized 85% of foci considered inconclusive on planar
Another search in Medline/Pubmed was performed via PICO. The search was done as follows. Patient/Problem: neoplasm, Intervention: Diffusion weighted imaging , Compare to: fdg, Outcome: accuracy. This gave a total of 26 results. From these 26 articles 5 were included into this review (2) (3) (4) (5) (6). Exclusion of articles was based on: the absence of statistical numbers, not being a clinical trial, and the participation of less than 25 patients.
The most important prognostic factor is presence of cervical lymph node metastases which can decrease the 5-year survival rate lower than 50% (Capote et al., 2007). Staging of neck by palpation and imaging techniques are not sensitive enough in detecting micrometastasis resulting in high incidence of occult metastases in neck (Hornstra et al., 2008). These techniques are based primarily on size and shape, with nodes smaller than 10 mm not generally considered suspicious and enlarged reactive nodes often get confused and considered suspicious. However, nodes as small as 2.0 mm can contain micrometastatic disease (Don et al., 1995) and therefore there is still chance of occult nodal metastasis in necks categorized as N0 and no metastases at
For oropharyngeal cancers requiring bilateral neck irradiation, IMRT or VMAT is the ideal treatment delivery option, as this removes the need for the anterior neck beam matching, and reduces the risk of xerostomia and dysphagia (Barrett et al., 2009, 141).
When CT perfusion?. The perfusion CT parameters were obtained and analyzed. After that, all patients were routinely followed up by ENT examination and contrast-enhanced CT scan of the nasopharynx and neck for two years. During two years follow-up, the patient who had the suspicious foci of recurrence from ENT examination or conventional CT will undergo tissue diagnosis.
The authors begin defending their stance by providing several reasons for the recent surge of CT procedures: rapid technological advances, convenience to the patient and cost effectiveness (David & Hall, 2007). The calculated dose a patient receives from a CT procedure is only an estimated exposure dose. To date, a patient’s
These scores tell me the way I think and how I tend to make decisions. From the scores above my two strong suits are Intuitive (38%) and Judging (38%) whereas; my weaknesses are Introvert (9%) and Thinking (9%). This also means that I am classified as an INTJ( Introverted, Intuitive, Thnking, Judging) which is also known as a Mastermind. INTJ’s are self-confident and tend to excel in careers such as sciences and engineering. Currently, I am a Micro Computer Support Assistant for LAUSD and being an INTJ type has allowed me to excel in this position because I am able to use my problem solving skills to try and figure out a certain problem even if I may not know the exact solution. But it is not always a good thing because INTJ’s tend to take
Therefore the fractionation effect is smaller in early responding tissues than in late responding tissues. When talking about fractionation response, tumors tend to behave similar to early responding tissues providing that late reactions are dose limiting5 Hyperfractionation is based on the difference between the response of early and late responding tissues. One benefit is that hyperfractionation can be effective even if tumors have high sensitivity by looking at their alpha/beta ratios. Usually hyperfractionation is generally expected to have an escalation of total dose which increases control rate without increasing the risk of late complications5 5-year survival for head and neck cancers that were treated with radiation therapy alone were reported below 60%, treatment failure were due to the high rate of local recurrence or distant metastasis.4 Local recurrence was due to active proliferation of the tumor cell left behind in the surgical field. In this report we will be looking at two different types of radiation treatment for head and neck cancers and their effects on the rate of control at the end of treatment time in mainly fast growing tumors, which are more sensitive to radiation. Loco regional control is an important key to patients’ long-term survival. Conventional fractionation or also known as standard fractionation is