CAISS EXAM (2025/2026 UPDATED VERSION) – COMPLETE TEST BANK WITH
CORRECT ANSWERS AND DETAILED RATIONALES/ACTUAL EXAM QUESTIONS
WITH /GRADE A+ ASSURED
Question 1
A communication between an injured internal carotid artery and the cavernous sinus or orbital
veins that causes the veins to swell and press against ocular nerves is known as:
A) Arteriovenous Malformation
B) Carotid Cavernous Fistula
C) Cavernous Angioma
D) Internal Carotid Stenosis
E) Ophthalmic Artery Aneurysm
Correct Answer: B) Carotid Cavernous Fistula
Rationale: A Carotid Cavernous Fistula (CCF) is a specific traumatic or spontaneous
vascular abnormality. In this condition, arterial blood from the internal carotid artery
enters the venous system of the cavernous sinus. Because the venous system is not designed
for high-pressure arterial flow, the veins swell (engorgement), which can lead to
compression of the cranial nerves (III, IV, and VI) passing through the sinus, resulting in
visual symptoms, proptosis, and bruits.
Question 2
In anatomical terminology, the term "Carpal" refers specifically to which structure?
A) The ankle bones
B) The bones of the wrist
C) The long bones of the hand
D) The elbow joint
E) The small bones of the toes
Correct Answer: B) Refers to the wrist as the carpal bones.
Rationale: The carpus consists of eight small, irregularly shaped bones that make up the
wrist. These are distinct from the "metacarpals" (bones of the hand) and the "tarsals"
(bones of the ankle). In AIS coding, injuries to the carpal bones are categorized under the
Extremities chapter.
, 2
Question 3
Where is the "Cavernous Sinus" located?
A) In the abdomen near the liver
B) Behind the sternum in the chest
C) On either side of the body of the sphenoid bone in the dura mater
D) Within the pelvic cavity near the sacrum
E) Inside the knee joint capsule
Correct Answer: C) Either of two sinuses of the dura mater, located at either side of the body
of the sphenoid bone.
Rationale: The cavernous sinus is a large collection of thin-walled veins located in the
middle cranial fossa. It is anatomically significant because it contains the internal carotid
artery and several cranial nerves. It extends from the superior orbital fissure in the front to
the petrous portion of the temporal bone in the back.
Question 4
The "Cauda Equina" is a collection of spinal nerve roots that:
A) Exit the brainstem to control facial muscles
B) Descend from the lower part of the spinal cord and resemble a horse's tail
C) Connect the rib cage to the thoracic spine
D) Control the rhythmic beating of the heart
E) Form the primary structure of the optic nerve
Correct Answer: B) Collection of spinal nerve roots descending from the lower part of the
spinal cord: their appearance resembles a horse's tail.
Rationale: The spinal cord typically ends at the L1-L2 vertebral level. The remaining nerve
roots continue down the spinal canal before exiting at their respective levels. This bundle of
nerves is called the "cauda equina" due to its physical resemblance to a horse's tail.
Injuries here are coded differently than injuries to the spinal cord itself.
Question 5
A patient presents with dull aching pain in the perineum, bladder, and sacrum, along with
associated paresthesia and areflexic paralysis. Which syndrome is most likely?
A) Brown-Séquard Syndrome
, 3
B) Central Cord Syndrome
C) Cauda Equina Syndrome
D) Anterior Cord Syndrome
E) Whiplash Associated Disorder
Correct Answer: C) Cauda Equina Syndrome
Rationale: Cauda Equina Syndrome is a medical emergency caused by the compression of
the nerve roots in the lower spinal canal. The clinical hallmarks provided in the
definition—perineal pain (saddle anesthesia), bladder dysfunction, and radiation in a
sciatic fashion with paralysis—reflect the loss of function in the nerve roots that supply the
lower extremities and pelvic organs.
Question 6
Which part of the brain occupies the posterior cranial fossa and is primarily concerned with the
coordination of movements?
A) Cerebrum
B) Brain Stem
C) Thalamus
D) Cerebellum
E) Medulla Oblongata
Correct Answer: D) The part of the brain that occupies the posterior cranial fossa behind
the brain stem and is concerned in the coordination of movements.
Rationale: The cerebellum (meaning "little brain") is essential for motor control. It does not
initiate movement but contributes to coordination, precision, and accurate timing. It
receives input from sensory systems of the spinal cord and from other parts of the brain to
fine-tune motor activity.
Question 7
A "Cerebral Infarction" is best defined as:
A) A bleed between the dura and the skull
B) A widespread shearing of white matter axons
C) An ischemic condition producing a persistent focal neurological deficit
D) A transient alteration in consciousness after a blow to the head
, 4
E) A type of tumor within the cerebrum
Correct Answer: C) An ischemic condition of the brain producing a persistent focal
neurological deficit in the area of distribution of one of the cerebral arteries.
Rationale: Unlike a hemorrhage (bleeding), an infarction is the death of brain tissue due to
a lack of blood supply (ischemia). In AIS, this is often associated with a vessel injury such
as a traumatic dissection or thrombosis of the carotid or vertebral arteries.
Question 8
Which structure forms the largest part of the central nervous system and consists of two
hemispheres united by the corpus callosum?
A) Cerebellum
B) Cerebrum
C) Pons
D) Diencephalon
E) Spinal Cord
Correct Answer: B) The main portion of the brain, occupying the upper part of the cranial
cavity: its two hemispheres united by the corpus callosum form the largest part of the
central nervous system.
Rationale: The cerebrum is the most superior part of the brain and is responsible for high-
level functions including thought, memory, and voluntary muscle movements. It is the
primary structure evaluated for focal injuries like contusions and hematomas in AIS
coding.
Question 9
"Chordae Tendineae" are tendinous cords found within which organ?
A) The brain
B) The lungs
C) The heart
D) The liver
E) The kidneys
Correct Answer: C) The tendinous cords that connect each cusp of the two-atrioventricular
valves to appropriate papillary muscles in the heart ventricles.
CORRECT ANSWERS AND DETAILED RATIONALES/ACTUAL EXAM QUESTIONS
WITH /GRADE A+ ASSURED
Question 1
A communication between an injured internal carotid artery and the cavernous sinus or orbital
veins that causes the veins to swell and press against ocular nerves is known as:
A) Arteriovenous Malformation
B) Carotid Cavernous Fistula
C) Cavernous Angioma
D) Internal Carotid Stenosis
E) Ophthalmic Artery Aneurysm
Correct Answer: B) Carotid Cavernous Fistula
Rationale: A Carotid Cavernous Fistula (CCF) is a specific traumatic or spontaneous
vascular abnormality. In this condition, arterial blood from the internal carotid artery
enters the venous system of the cavernous sinus. Because the venous system is not designed
for high-pressure arterial flow, the veins swell (engorgement), which can lead to
compression of the cranial nerves (III, IV, and VI) passing through the sinus, resulting in
visual symptoms, proptosis, and bruits.
Question 2
In anatomical terminology, the term "Carpal" refers specifically to which structure?
A) The ankle bones
B) The bones of the wrist
C) The long bones of the hand
D) The elbow joint
E) The small bones of the toes
Correct Answer: B) Refers to the wrist as the carpal bones.
Rationale: The carpus consists of eight small, irregularly shaped bones that make up the
wrist. These are distinct from the "metacarpals" (bones of the hand) and the "tarsals"
(bones of the ankle). In AIS coding, injuries to the carpal bones are categorized under the
Extremities chapter.
, 2
Question 3
Where is the "Cavernous Sinus" located?
A) In the abdomen near the liver
B) Behind the sternum in the chest
C) On either side of the body of the sphenoid bone in the dura mater
D) Within the pelvic cavity near the sacrum
E) Inside the knee joint capsule
Correct Answer: C) Either of two sinuses of the dura mater, located at either side of the body
of the sphenoid bone.
Rationale: The cavernous sinus is a large collection of thin-walled veins located in the
middle cranial fossa. It is anatomically significant because it contains the internal carotid
artery and several cranial nerves. It extends from the superior orbital fissure in the front to
the petrous portion of the temporal bone in the back.
Question 4
The "Cauda Equina" is a collection of spinal nerve roots that:
A) Exit the brainstem to control facial muscles
B) Descend from the lower part of the spinal cord and resemble a horse's tail
C) Connect the rib cage to the thoracic spine
D) Control the rhythmic beating of the heart
E) Form the primary structure of the optic nerve
Correct Answer: B) Collection of spinal nerve roots descending from the lower part of the
spinal cord: their appearance resembles a horse's tail.
Rationale: The spinal cord typically ends at the L1-L2 vertebral level. The remaining nerve
roots continue down the spinal canal before exiting at their respective levels. This bundle of
nerves is called the "cauda equina" due to its physical resemblance to a horse's tail.
Injuries here are coded differently than injuries to the spinal cord itself.
Question 5
A patient presents with dull aching pain in the perineum, bladder, and sacrum, along with
associated paresthesia and areflexic paralysis. Which syndrome is most likely?
A) Brown-Séquard Syndrome
, 3
B) Central Cord Syndrome
C) Cauda Equina Syndrome
D) Anterior Cord Syndrome
E) Whiplash Associated Disorder
Correct Answer: C) Cauda Equina Syndrome
Rationale: Cauda Equina Syndrome is a medical emergency caused by the compression of
the nerve roots in the lower spinal canal. The clinical hallmarks provided in the
definition—perineal pain (saddle anesthesia), bladder dysfunction, and radiation in a
sciatic fashion with paralysis—reflect the loss of function in the nerve roots that supply the
lower extremities and pelvic organs.
Question 6
Which part of the brain occupies the posterior cranial fossa and is primarily concerned with the
coordination of movements?
A) Cerebrum
B) Brain Stem
C) Thalamus
D) Cerebellum
E) Medulla Oblongata
Correct Answer: D) The part of the brain that occupies the posterior cranial fossa behind
the brain stem and is concerned in the coordination of movements.
Rationale: The cerebellum (meaning "little brain") is essential for motor control. It does not
initiate movement but contributes to coordination, precision, and accurate timing. It
receives input from sensory systems of the spinal cord and from other parts of the brain to
fine-tune motor activity.
Question 7
A "Cerebral Infarction" is best defined as:
A) A bleed between the dura and the skull
B) A widespread shearing of white matter axons
C) An ischemic condition producing a persistent focal neurological deficit
D) A transient alteration in consciousness after a blow to the head
, 4
E) A type of tumor within the cerebrum
Correct Answer: C) An ischemic condition of the brain producing a persistent focal
neurological deficit in the area of distribution of one of the cerebral arteries.
Rationale: Unlike a hemorrhage (bleeding), an infarction is the death of brain tissue due to
a lack of blood supply (ischemia). In AIS, this is often associated with a vessel injury such
as a traumatic dissection or thrombosis of the carotid or vertebral arteries.
Question 8
Which structure forms the largest part of the central nervous system and consists of two
hemispheres united by the corpus callosum?
A) Cerebellum
B) Cerebrum
C) Pons
D) Diencephalon
E) Spinal Cord
Correct Answer: B) The main portion of the brain, occupying the upper part of the cranial
cavity: its two hemispheres united by the corpus callosum form the largest part of the
central nervous system.
Rationale: The cerebrum is the most superior part of the brain and is responsible for high-
level functions including thought, memory, and voluntary muscle movements. It is the
primary structure evaluated for focal injuries like contusions and hematomas in AIS
coding.
Question 9
"Chordae Tendineae" are tendinous cords found within which organ?
A) The brain
B) The lungs
C) The heart
D) The liver
E) The kidneys
Correct Answer: C) The tendinous cords that connect each cusp of the two-atrioventricular
valves to appropriate papillary muscles in the heart ventricles.
