1 / 20

Radiotherapy in ENT

Radiotherapy in ENT. The main target is the DNA which, when hardly damaged, can lead to cell death and therefore tumour necrosis. . Ionise air Pass through matter which is generally opaque to light Affect photographic plates. Electromagnetic Particulate

savoie
Download Presentation

Radiotherapy in ENT

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Radiotherapy in ENT

  2. The main target is the DNA which, when hardly damaged, can lead to cell death and therefore tumournecrosis. 

  3. Ioniseair • Pass through matter which isgenerally • opaque tolight • Affect photographicplates

  4. Electromagnetic • Particulate •  Electromagnetic wave of wavelength less than 1 angstromare • calledphotons. •  They have neither mass nor charge. Measuredinelectron volt. eg x- rays and gammarays. •  Particulate radiation have mass and arechargednegatively (electrons), positively ( protons, alpha particles) or are neutral (neutrons)  Twocategories

  5. Injury to cellularstructures • Breakdown of cellularproteins • Radiosensitivity • Lymphocytes • Granularleucocytes • Epithelialcells • Endothelial cells of blood vessels, pleura.Peritoneum • Connective tissuecells • Musclecells • Bonecells • Nervecells

  6. External beamradiotherapy Brachytherapy-moulds, interstitial implants, intracavitaryimplants

  7. Kilo voltage machines – 50 – 400kV Cobalt 60 –1.2mV Linear accelerator, netatron or microtron– 4.25mV 4. Radioactive material likecesium137, iridium 192, gold 198 and iodine125

  8.  Size oftumour  Relative depth in thebody  The anatomicalsite  Its relativeradiosensitivity  The period of itsevolution  Composition of the tissues of the tumourbed

  9.  Radiation therapy is delivered in theseries of treatment orfractions. “Conventionalfractionation”  total dose - 6500 to7200cGy  daily fractions-180-200cGy  period-7weeks  given Monday throughfriday

  10. Allows regular reoxygenation of the tumor during the course of treatment, making it more radiosensitive. • Offers radiation to effect more tumor cellsduring • the radiosensitive phase of their cellcycle. • Normal cell seems to recover more completely between fractions from sublethal damage than do tumorcells.

  11.  Method of radiation treatment inwhichsealed radioactive source is used to deliver the dose to a short distance by interstitial(direct insertion into tissue), intracavitary(placement within a cavity) or surfaceapplication(molds). (Boost for advanced tumors or primarily forsmall lesions)

  12.  Most commonly used radioisotopeinhead and neck regions are iridium 192, cesium137 and radium226.  Radiation sources may be formofneedles, narrow tubes, wires or smallbeads.

  13.  Inhomogeneity.  Requires the operator to haveadequatetechnical and conceptual skills to achieve good dose distribution.  Exposure to room personnel and totherapist specially with the use of radiumneedles.

  14. Supportive Curative Palliative Symptomatic

  15.  Decision regarding the use of radiationand/orsurgery for the control of primary lesion is a function of the location and extent of thetumor.  carcinoma of nasopharynx, base of tongue,softpalate, tonsillar fossa radiation therapy is the treatment of choice because of surgical morbidity, difficult access, and high risk of regional lymph nodeinvolvement.

  16.  Carcinoma of salivary gland andalveolarridge should be treated surgically followed by radiotherapy due to potential for bony infiltration.  Early carcinoma of glottic larynx andtongueare equally well controlled by radiation or surgery but radiation offer a better functionalresult  Hard deeply infiltrated carcinomas oftongueare less likely to be controlled by radiation. (superficial / exophytic lesions have higher cure rate with radiation than deeply infiltratedlesions)

  17. Nutrition • OralHygiene • Skincare • Eyecare

  18. THANK YOU

More Related