GROSS ANATOMY

GROSS ANATOMY

BRACHIAL PLEXUS

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Horner’s syndrome is due to the involvement of
A
C 5, 6, 7 root
B
C 8, T 1 trunk
C
C 7, C 8 root
D
C 5, C 6 trunk
Explanation: 

Detailed explanation-1: -Introduction: Horner’s syndrome consists of sympathetic ocular paralysis, with lesions occurring at different levels. When it’s associated with involvement of the C8-T1 roots, the commonest causes are the tumours responsible for Pancoast’s syndrome.

Detailed explanation-2: -Horner syndrome is caused by damage to a certain pathway in the sympathetic nervous system. The sympathetic nervous system regulates heart rate, pupil size, perspiration, blood pressure and other functions that enable you to respond quickly to changes in your environment.

Detailed explanation-3: -In individuals with Horner syndrome, the anisocoria is greater in darkness than in light. The affected pupil dilates more slowly than the normal pupil does because the affected pupil lacks the pull of the dilator muscle (ie, dilation lag).

Detailed explanation-4: -In most cases, the physical findings associated with Horner syndrome develop due to an interruption of the sympathetic nerve supply to the eye due to a lesion or growth. The lesion develops somewhere along the path from the eye to the region of the brain that controls the sympathetic nervous system (hypothalamus).

There is 1 question to complete.