1.
Which of the following areas is most commonly site used to draw a sample of the cerebrospinal fluid?
Correct Answer
A. Lumbar cistern
Explanation
The most commonly used site to draw a sample of cerebrospinal fluid is the lumbar cistern. This area, located in the lower back, is accessed through a lumbar puncture procedure. It is a preferred site because it allows for easy access to the cerebrospinal fluid without the need for invasive procedures. The lumbar cistern is also a relatively safe site for obtaining a sample, with minimal risk of complications.
2.
From the picture, where is the most likely site of the obstruction?
Correct Answer
C. Cerebral aqueduct
Explanation
The cerebral aqueduct is the narrow channel that connects the third and fourth ventricles in the brain. It is responsible for the flow of cerebrospinal fluid (CSF) between these two ventricles. If there is an obstruction in this area, it can disrupt the normal flow of CSF, leading to a condition called hydrocephalus. Therefore, based on the given information, the most likely site of the obstruction would be the cerebral aqueduct.
3.
A sample of CSF obtained from LP showed a xanthochromic appearance. What is the most likely diagnosis
Correct Answer
C. Subarachnoid hemorrhage
Explanation
The xanthochromic appearance of the CSF suggests the presence of bilirubin, which is a breakdown product of hemoglobin. This indicates that there has been bleeding in the subarachnoid space, most likely due to a subarachnoid hemorrhage. Epidural hemorrhage, subdural hemorrhage, and intracerebral hemorrhage would not typically cause xanthochromia in the CSF. Traumatic tapping refers to a procedure rather than a diagnosis, so it is not the most likely explanation for the xanthochromic appearance.
4.
From the picture, where is the site of obstruction?
Correct Answer
B. Right foramen of Monro
Explanation
The site of obstruction in the given picture is the right foramen of Monro.
5.
A patient presented with subacute headache and fever. Examination showed positive stiffneck and Kernig sign. Where is the most likely site of the disease?
Correct Answer
D. Meninges
Explanation
Given the patient's symptoms of subacute headache and fever, along with positive signs of stiff neck and Kernig sign, the most likely site of the disease is the meninges. The meninges are the membranes that cover and protect the brain and spinal cord, and inflammation of the meninges, known as meningitis, can cause these symptoms. The other options, such as the occipital lobe, basilar artery, cervical spine, and vertebral artery, are less likely to be the primary site of the disease based on the given symptoms and signs.
6.
A CSF profile shows WBC 6 cell/ml, protein 55 mg/dL, glucose 30 mg/dL. Is this CSF profile normal or abnormal?
Correct Answer
B. Abnormal
Explanation
The CSF profile shows an elevated white blood cell count (WBC) of 6 cells/ml, which indicates an inflammatory response in the central nervous system. Additionally, the protein level of 55 mg/dL is higher than the normal range, suggesting possible damage or infection. The glucose level of 30 mg/dL is lower than the expected range, indicating impaired glucose metabolism. These abnormal findings in the CSF profile indicate an abnormal condition rather than a normal one.
7.
Some pyrogens can enter the brain tissue and cause fever. Where is the most likely site of entry for these pyrogens?
Correct Answer
C. Lamina terminalis
Explanation
The lamina terminalis is a thin membrane located in the brain that separates the anterior and posterior regions. It is in close proximity to the third ventricle, which is a fluid-filled space that surrounds the brain. Pyrogens, substances that can cause fever, can enter the brain tissue by crossing the blood-brain barrier. The lamina terminalis is a potential site of entry for these pyrogens as it is located near the third ventricle, allowing them to easily access the brain tissue and cause fever.
8.
A patient had a brain tumor. He began to develop visual blurring and had other symptoms of increased intracranial pressure. What would be the most likely sign that you can examine and find in the visual examination?
Correct Answer
B. Enlarged blind spot
Explanation
The most likely sign that can be found in the visual examination of a patient with a brain tumor and symptoms of increased intracranial pressure is an enlarged blind spot. This can occur due to compression or damage to the optic nerve, leading to a decrease in visual acuity and an enlargement of the blind spot in the visual field. This finding is consistent with the patient's visual blurring and other symptoms, indicating the presence of a brain tumor affecting the optic nerve.