All of the following clinical findings are seen in Horner’s syndrome, except
**Core Concept**
Horner's syndrome is a neurologic disorder that results from disruption of the sympathetic nerves supplying the eye, leading to a characteristic triad of symptoms: ptosis (drooping eyelid), miosis (constricted pupil), and anhidrosis (absence of sweating). The condition can be caused by various factors, including stroke, trauma, tumors, or congenital anomalies.
**Why the Correct Answer is Right**
The characteristic features of Horner's syndrome are due to the loss of sympathetic innervation to the eye. The sympathetic nerves release norepinephrine, which stimulates the dilator pupillae muscle to cause pupil dilation. In Horner's syndrome, the loss of sympathetic input leads to unopposed parasympathetic activity, resulting in pupil constriction (miosis). Additionally, the loss of sympathetic innervation to the superior tarsal muscle causes ptosis. Anhidrosis, or the absence of sweating, occurs due to the loss of sympathetic innervation to the sweat glands.
**Why Each Wrong Option is Incorrect**
* **Option A:** Miosis is a characteristic feature of Horner's syndrome, not an exception.
* **Option B:** Ptosis is a classic symptom of Horner's syndrome, making it an incorrect option.
* **Option D:** The correct answer is not provided, but typically, anhidrosis is a symptom of Horner's syndrome.
**Clinical Pearl / High-Yield Fact**
Horner's syndrome can be a sign of an underlying serious condition, such as a stroke or a tumor. It is essential to investigate the cause of Horner's syndrome thoroughly to provide proper treatment.
**Correct Answer:** Not provided in the question.