Designing And Creating An Imaging Department Essay

When used in a manner that is not controlled, ionization radiation emanating from radio-active sources or x-rays can be harmful to the uses. The damage from ionization radiation is not only harmful to the person they are exposed to, but also to their descendants through the inherited effects. Ionization radiation is used for medical purposes because of its colossal benefits to the patients for the purposes of nuclear medicine and diagnostic radiology, ionization radiations are extremely invaluable. This is because they allow for the treatment of illnesses such as cancer and the detection of various medical conditions. Due to the proven benefits of ionization radiations, it is imperative that organizations that are creating new imaging departments incorporate measure to protect the staff from the harmful effects of ionization radiations (National Health Service, 2009).

Design and Construction of the Fluoroscopic Suite and the Digital Imaging Suite

The design of the fluoroscopic suite and the Digital Imaging Suite should have the flowing features:
The design and the construction of the room should be so that the radiographer can see people accessing the room using the patient entrance door.
The design and construction of the room, in addition to the installation should allow the X-ray tube of the fluoroscopic device to move 40o of the subtended arc at a distance of 120 centimeters about the midpoint of the table.
The design and construction of the room should allow the patient access doors to be locked when some procedures are being performed. This is in order to afford patients the due privacy. It is recommended that thumb locks are used so that they are accessible in the case of a fire.
The design should also allow the patient access doors to open inwards towards the examination rooms. This is in order prevent the inadvertent entry into the room when procedures are underway.
A lead-lined door on the entrance way to the control area should be installed in order to protect from ionization radiation (National Health Service, 2001).

Control and Uncontrolled Areas

Part of the policy guidelines for an imaging department is the restricted and unrestricted areas. Restricted areas within the imaging department are those areas to which access is limited. The intention of this restriction is to protect individuals from unnecessary and undue risks that emanate from the exposure to radioactive material or ionization radiation (Mettler & Guiberteau, 2012). These areas within the imaging department include high radiation areas, radiation areas such as imaging rooms, and rooms or areas where radioactive materials in amounts that necessitate the use of the “Caution: Radioactive Material” sign in accordance with regulatory procedures are required. Unrestricted areas within the imaging department are those areas to which access is not controlled or restricted by the imaging department or regulatory guidelines. Some of the unrestricted areas in the imaging department include the reception area and he waiting rooms (National Health Service, 2001).

Orientation of X-ray Machines

The location of an X-ray machine and its orientation in a room is very important. Various distances that are used in calculations are measured with the location of the machine as the focal point. This is also important to the inverse square law, as it is influential in determining the dosage of X-ray beams. The orientation and positioning of the x-ray machines in the room is also important to the directions of the direct or the primary X-Ray beam. Considering all these factors, the most suitable location and orientation of the X-ray machine in the room is at the middle of the room in a lateral orientation (Schueler, n.d.).

Direction of Useful Beam

Ideally, the x-ray machines are placed in an overhead position so that the beams drop down on the patient lying on a platform. When the x-rays are produced, they travel in all directions. However, the useful beam needs to be directed in order to achieve the imaging needs required. In this regard, the useful beam is restricted to a downward general direction using restriction devices such as collimators. This allows the primary beam to travel from the source of the x-rays in order to irradiate the patient.
The layout and construction of the control area is done using the specifications and requirements similar to those of the imaging suites. However, control areas need to be longer so as to incorporate the installation of large sizes of monitoring and control equipment. This is especially the case where universal fluoroscopy equipment is installed in the imaging department. The control area should also have a monitor, imaging computed and its interface, a video recorder and the corresponding storage and enough space to accommodate at least four clinical staff, room for the storage of lead aprons and an outer door for patient privacy reasons (National Health Service, 2001).

Protective Structural Shielding

Various elements are required as part of the protective structural shielding. One of the major elements is the protective screens. The requirement for these screens is 15 kg m-2 or an equivalent of 1.3 millimeters. In case the protective screen is located less than two meters away from the patient or x-ray tube, the requirements might be higher. The walls should have an equivalent of 1 millimeter lead shielding in the least for every 100kVp that is required. A lead shielding of 10Kg m-2 is sufficient for door to the other rooms in the imaging department. However, a higher standard of 15 Kg m-2 is required for doors leading to the imaging rooms. Where the entry into the imaging rooms is not under the control of the operator, the installation of warning lights at the entrance is required (National Health Service, 2001).

Example of Calculation for Shielding

The lead shielding that is required in order to reduce the rate of exposure from 32mR/hr in an I-131 source to 2mR/hr considering that the HVL for lead in an I-131 source is 0.178 centimeters
2n = Io/I = 32mR/hr / 2mR/hr

2n – 16

n = 4

4HVL x 0.178 cm/HVL

= 0.71cm

Primary and Secondary Barriers

The following are some of the primary barriers:
Lead lining in the casing of X-ray tubes
Extra shielding on the ceiling and floors of the X-ray rooms
Extra shielding on walls (Forster, 1985).
The following are some of the secondary barriers:
The protective cubicle of the radiographer
Barium plaster used in the ceiling and walls of X-ray rooms
Lead rubber gloves and aprons (Forster, 1985).
Selection of Construction Material
Various factors influence the selection of construction material.
Density of material: Low-density materials are not appropriate because they can disperse neutrons.
Concentration of hydrogen: materials that have high concentration of hydrogen are efficient barriers for neutrons.
Thickness of material: thicker materials are preferred to thin materials.
Design of Radiation-absorbent barriers
Several designs are used for radiation-absorbent barriers. One of the designs is the use of metal grains as the radiation absorbents. These grains have an average grain size of between 0.5 millimeters to 5 millimeters. This design is advantageous because the thickness of the absorbent material can be altered for different rooms in the imaging department. Alternatively, particulate material can be used as the radiation absorbents. When this is compared to the use of metal grains, the particulate material has a small particle size. For the same weight, the particulate material will have a higher density, one of the defining factors of appropriate radiation protection material. The design incorporating particulate material is the best because it generates protective material of high density for the same weight.

References

Forster, E. (1985). Equipment for diagnostic radiography. Lancaster, England: MTP Press.
Mettler, F. A., & Guiberteau, M. J. (2012). Essentials of nuclear medicine imaging. Philadelphia, PA: Elsevier/Saunders.
National Health Service. (2001). Facilities for Diagnostic Imaging and Interventional Radiology. Retrieved from https://www.gov.uk/government/uploads/system/uploads/ attachment_data/file/149183/HBN_6_V1_DSSA.pdf
National Health Service. (2009). Radiation Protection for Staff in the Medical Use of Ionising Radiation and Lasers. Retrieved from http://www.newcastle-hospitals.org.uk/downloads /policies/radiology/radprotstaffionisinglasers200604.pdf
Schueler, B. (n.d.). Personal protection during fluoroscopic procedures. Retrieved from http://www.aapm.org/meetings/03AM/pdf/9790-14134.pdf