Question

Aqueduct of Sylvius is another name for 
(a) Aqueous chamber
(b) Central canal
(c) Foramen of Monro
(d) Iter 

Answer 1

Hint: The Aqueduct of Sylvius connects the third and fourth ventricle of the brain. It was named by Franciscus Sylvius. Aqueduct of Sylvius is also known which is the same as the abbreviation of ‘International Thermonuclear Experimental Reactor’.

Complete answer:
The Sylvius Aqueduct connects the third and the fourth ventricle and is often known as Iter. The third ventricle is in the centre of the diencephalon and the fourth ventricle is in the centre of the pons and the cerebellum.
- The cerebral aqueduct (of Sylvius) is the structure that connects the third ventricle to the fourth ventricle in the brainstem. It is situated within the midbrain, surrounded by periaqueductal grey matter (PAG) , with the midbrain tectum posteriorly and the tegmentum anteriorly. It is filled with cerebrospinal fluid (CSF) and its blockage contributes to obstructive hydrocephalus with lateral and third dilatation.
- Within the midbrain is the cerebral aqueduct that consists of aqueductus mesencephali, mesencephalic duct, Sylvian aqueduct, or aqueduct of Sylvius. It contains cerebrospinal fluid ( CSF) and binds the third ventricle to the fourth ventricle, dorsal to the pons, and ventricular to the cerebellum; The cerebral aqueduct is surrounded by a grey matter ring called the periaqueductal grey or central grey.
- The cerebral aqueduct acts as a channel that passes through the midbrain and links the third ventricle to the brain's fourth ventricle, and the cerebrospinal fluid (CSF) follows its natural path through the cerebral ventricles and the canal that connects these ventricles.
So, the correct answer is, ‘(d) Iter‘.

Note: Hydrocephalus is the accumulation of fluid deep inside the brain, in the cavities (ventricles) . The extra fluid raises the size of the ventricles and puts the brain under pressure. Normally, the cerebrospinal fluid flows into the ventricles and bathes the brain and spinal column. The extra fluid places the brain under pressure and can cause brain damage. It is most prominent in infants and older adults. Hydrocephalus in infants is distinguished by a head enlargement. Adults and older children suffer fatigue, visual impairment, cognitive disorders, lack of balance, and incontinence.