24 - Unilateral hyperlucent lung causes

1. Absence of a breast in a patient after mastectomy for breast cancer,
2. Absence of a pectoralis muscle in a patient with Poland's syndrome,
3. Unilateral bullous disease/emphysema
4. Air trapping on expiration in a patient with Swyer-James syndrome
5. An endobronchial foreign body

23 - Radiation sources for Brachytherapy

Commonly used radiation sources (radionuclides) for brachytherapy

Radionuclide	Type	Half-life	Energy
Caesium-137 (137Cs)	γ-ray	30.17 years	0.662 MeV
Cobalt-60 (60Co)	γ-rays	5.26 years	1.17, 1.33 MeV
Iridium-192 (192Ir)	γ-ray	74.0 days	0.38 MeV (mean)
Iodine-125 (125I)	X-rays	59.6 days	27.4, 31.4 and 35.5 keV
Palladium-103 (103Pd)	X-ray	17.0 days	21 keV (mean)
Ruthenium-106 (106Ru)	β-particles	1.02 years	3.54 MeV