Final answer:
The claim that a rapidly intumescent lens or a traumatic cataract can result in pupillary block and angle closure is true. This condition is significant because it can lead to increased intraocular pressure and potentially cause angle closure glaucoma.
Step-by-step explanation:
The statement that a rapidly intumescent lens or a traumatic cataract can lead to pupillary block and angle closure is true. A cataract, which is a cloudiness in the lens of the eye, can swell and become intumescent, particularly after a trauma. This swollen lens blocks the normal flow of aqueous humor through the pupil to the anterior chamber of the eye, leading to increased intraocular pressure. When the fluid cannot circulate properly, it leads to pupillary block, which in turn can cause angle closure glaucoma. This is a situation where the iris is pushed or pulled up against the trabecular meshwork at the angle of the anterior chamber, impeding the outflow of the aqueous humor and raising intraocular pressure, which can damage the optic nerve and lead to vision loss if not treated.