Modern radiation delivery technique aims at precise delivery of radiation dose like Stereotactic Body Radiotherapy, 3D Conformal Radiotherapy and Intensity Modulated Radiotherapy are commonly using now a days. These techniques are based on increased complexity of radiation delivery methods and therefore necessitate verification of computer calculated dose distribution by an accurate dosimetric method. Gel dosimeters absorb dose in a tissue-equivalent manner and capable of recording dose distributions 3 dimensionally. An Optical CT (OCT) scanner plays a major role for Gel dosimeter readout and in clinical radiation therapy as a 3-Dimensional Radiation Dosimetry.