Grenz Rays
Encyclopedia
Grenz Rays are part of the electromagnetic spectrum comprising low energy (ultrasoft) X-rays. These were first developed by Gustav Bucky in 1923 using a cathode vacuum tube with a Lithium borate glass window which he labeled Grenz rays as he believed that the biological effects resembled UV light & traditional X-rays and hence was on the border between the two (Grenz = border in German). These rays are also known as Bucky rays.(Ref 1.)
Grenz rays are produced by specially calibrated X-ray machines generally operating in the 10-30 kV range to produce X-rays with HVL less than 0.035 mm Al (Ref2.) (HVL is half value layer & refers to a thickness of a given material that will cut the X-ray flux by 50%). Grenz rays are absorbed by air & therefore treatments must be given at fixed distances which the machine has been calibrated for. Grenz rays have a half value depth of 0.5mm & essentially absorbed within the first 2mm of skin (Ref3.). The exact mechanism of action is unknown but it does have effects on the Langerhans cell
s in the epidermis (Ref4,5)
Grenz rays are indicated for treatment of eczema
, psoriasis
, palmoplantar pustulosis, neurodermatitis and pruritus ani et vulvae. It has been reported to be helpful for lichen planus, Grover's disease, Darier's disease, & histiocytosis X.(Ref2.) Grenz ray has been used for treatment of actinic keratoses & Bowen's disease (Ref.1)
Grenz rays are produced by specially calibrated X-ray machines generally operating in the 10-30 kV range to produce X-rays with HVL less than 0.035 mm Al (Ref2.) (HVL is half value layer & refers to a thickness of a given material that will cut the X-ray flux by 50%). Grenz rays are absorbed by air & therefore treatments must be given at fixed distances which the machine has been calibrated for. Grenz rays have a half value depth of 0.5mm & essentially absorbed within the first 2mm of skin (Ref3.). The exact mechanism of action is unknown but it does have effects on the Langerhans cell
Langerhans cell
Langerhans cells are dendritic cells of the skin and mucosa, and contain large granules called Birbeck granules. They are present in all layers of the epidermis, but are most prominant in the stratum spinosum. They also occur in the papillary dermis, particularly around blood vessels, as well as...
s in the epidermis (Ref4,5)
Grenz rays are indicated for treatment of eczema
Eczema
Eczema is a form of dermatitis, or inflammation of the epidermis . In England, an estimated 5.7 million or about one in every nine people have been diagnosed with the disease by a clinician at some point in their lives.The term eczema is broadly applied to a range of persistent skin conditions...
, psoriasis
Psoriasis
Psoriasis is an autoimmune disease that appears on the skin. It occurs when the immune system mistakes the skin cells as a pathogen, and sends out faulty signals that speed up the growth cycle of skin cells. Psoriasis is not contagious. However, psoriasis has been linked to an increased risk of...
, palmoplantar pustulosis, neurodermatitis and pruritus ani et vulvae. It has been reported to be helpful for lichen planus, Grover's disease, Darier's disease, & histiocytosis X.(Ref2.) Grenz ray has been used for treatment of actinic keratoses & Bowen's disease (Ref.1)