Complications of Skull Base Surgery Indian Medical PG Practice Questions and MCQs
Practice Indian Medical PG questions for Complications of Skull Base Surgery. These multiple choice questions (MCQs) cover important concepts and help you prepare for your exams.
Complications of Skull Base Surgery Indian Medical PG Question 1: Cranial nerve 8 palsy is associated with all of the following symptoms except:
- A. Gag reflex (Correct Answer)
- B. Hearing loss
- C. Tinnitus
- D. Vertigo
Complications of Skull Base Surgery Explanation: ***Gag reflex***
- The **gag reflex** is primarily mediated by the **glossopharyngeal (CN IX)** and **vagus (CN X)** nerves.
- CN VIII, the vestibulocochlear nerve, is solely responsible for hearing and balance, and thus has no role in the gag reflex.
*Vertigo*
- **Vertigo** is a common symptom of CN VIII palsy, specifically involving the **vestibular branch** of the nerve.
- Damage to this branch can disrupt the sense of balance and spatial orientation.
*Hearing loss*
- **Hearing loss** is a hallmark symptom of CN VIII palsy, affecting the **cochlear branch** of the nerve.
- This can manifest as conductive, sensorineural, or mixed hearing loss, depending on the specific pathology.
*Tinnitus*
- **Tinnitus**, the perception of sound when no external sound is present, is frequently associated with CN VIII palsy.
- It often accompanies hearing loss and is a common complaint in conditions affecting the auditory system.
Complications of Skull Base Surgery Indian Medical PG Question 2: A lady comes to OPD after fall from scooty. Her vitals are stable. She is having continuous, clear watery discharge from nose after 2 days. This is most likely a feature of?
- A. CSF rhinorrhoea (Correct Answer)
- B. Acute respiratory infection
- C. Rhinitis
- D. Middle cranial fossa fracture
Complications of Skull Base Surgery Explanation: ***CSF rhinorrhoea***
- **Clear watery discharge** appearing **two days after head trauma** (fall from scooty) is highly suggestive of **cerebrospinal fluid (CSF) rhinorrhoea**.
- This occurs due to a breach in the **skull base**, allowing CSF to leak from the subarachnoid space into the nasal cavity.
*Acute respiratory infection*
- An acute respiratory infection typically presents with symptoms like **fever, cough**, and **nasal discharge** that is often thicker and discolored, not clear and watery.
- The onset of discharge two days after trauma without other signs of infection also makes this less likely.
*Rhinitis*
- Rhinitis involves inflammation of the nasal mucosa, leading to watery discharge, sneezing, and congestion.
- However, the traumatic etiology and the specific timing of the discharge make **CSF leak** a more pertinent diagnosis than simple rhinitis.
*Middle cranial fossa fracture*
- While a **middle cranial fossa fracture** can cause CSF leakage, the discharge from the nose (rhinorrhoea) typically originates from an **anterior cranial fossa fracture**.
- A middle cranial fossa fracture is more commonly associated with **otorrhoea** (CSF leakage from the ear) if the temporal bone is involved.
Complications of Skull Base Surgery Indian Medical PG Question 3: Which clinical sign can detect facial nerve palsy occurring due to the lesion at the outlet of stylomastoid foramen -
- A. Deviation of tongue towards opposite side
- B. Loss of sensation over right cheek
- C. Loss of taste sensation in anterior 2/3 of tongue
- D. Deviation of angle of mouth towards opposite side (Correct Answer)
Complications of Skull Base Surgery Explanation: ***Deviation of angle of mouth towards opposite side***
- A lesion of the facial nerve at the **stylomastoid foramen** specifically affects the motor innervation to the **muscles of facial expression**. [1]
- This leads to **paralysis of facial expression muscles** on the ipsilateral side, causing the mouth to **deviate towards the unaffected side** due to unopposed muscle action. [1]
*Deviation of tongue towards opposite side*
- **Tongue deviation** is primarily indicative of a lesion in the **hypoglossal nerve (CN XII)**, which controls the intrinsic and extrinsic muscles of the tongue.
- The facial nerve is not involved in **tongue movement**.
*Loss of sensation over right cheek*
- **Sensory innervation** to the face, including the cheek, is provided by the **trigeminal nerve (CN V)**, not the facial nerve.
- The facial nerve is primarily a **motor nerve** for facial expression, although it carries some sensory fibers for taste and a small area of the ear.
*Loss of taste sensation in anterior 2/3 of tongue*
- **Taste sensation** from the **anterior two-thirds of the tongue** is carried by the **chorda tympani nerve**, which is a branch of the facial nerve.
- However, the **chorda tympani branches off proximal to the stylomastoid foramen**, meaning a lesion at the foramen itself would not affect taste.
Complications of Skull Base Surgery Indian Medical PG Question 4: Frontal sinuses drain into:
- A. Superior meatus
- B. Middle meatus (Correct Answer)
- C. Ethmoid recess
- D. Inferior meatus
Complications of Skull Base Surgery Explanation: ***Middle meatus***
- The **frontal sinuses** drain via the **frontonasal duct** into the anterior part of the **middle meatus** through the **semilunar hiatus**.
- This drainage pathway is crucial for mucus clearance and ventilation of the frontal sinuses.
*Superior meatus*
- The **superior meatus** primarily receives drainage from the **posterior ethmoid air cells**.
- It handles drainage from different sinus structures located more superiorly and posteriorly.
*Inferior meatus*
- The **inferior meatus** is the sole drainage site for the **nasolacrimal duct**, which carries tears from the eye into the nasal cavity.
- It does not receive drainage from any of the paranasal sinuses.
*Ethmoid recess*
- The **sphenoethmoidal recess** (often referred to as ethmoid recess) is the drainage site for the **sphenoid sinus** and the **posterior ethmoid air cells**.
- The frontal sinus does not drain into this specific region.
Complications of Skull Base Surgery Indian Medical PG Question 5: Which of the following is not a complication of maxillary sinus lavage and insufflation?
- A. Orbital injury
- B. Epistaxis
- C. Facial nerve injury (Correct Answer)
- D. Air embolism
Complications of Skull Base Surgery Explanation: ***Facial nerve injury***
- The **facial nerve (CN VII)** passes through the parotid gland and temporal bone, far from the maxillary sinus.
- There is no anatomical proximity or procedural mechanism during maxillary sinus lavage and insufflation that would put the facial nerve at risk of injury.
*Air embolism*
- **Insufflation of air** into the maxillary sinus, especially under pressure, can lead to air entering the bloodstream if a blood vessel is inadvertently punctured.
- This can result in a serious and potentially fatal **air embolism**, particularly if the air reaches the cerebral circulation.
*Orbital injury*
- The **medial wall of the maxillary sinus** is in close proximity to the orbit, separated by thin bone.
- During lavage, excessive force or incorrect angulation of instruments can perforate this thin bone, leading to **orbital complications** such as periorbital hematoma or injury to orbital contents.
*Epistaxis*
- During the procedure, the **mucosa of the nasal cavity** or the sinus itself can be traumatized by the instruments used for lavage.
- This local trauma to the rich blood supply of these areas can easily cause **nasal bleeding (epistaxis)**.
Complications of Skull Base Surgery Indian Medical PG Question 6: CSF Otorrhea is due to trauma of:
- A. Tympanic membrane
- B. Cribriform plate
- C. Parietal bone
- D. Petrous temporal bone (Correct Answer)
Complications of Skull Base Surgery Explanation: ***Petrous temporal bone***
- **CSF otorrhea** (leakage of cerebrospinal fluid from the ear) most commonly results from a fracture of the **petrous portion of the temporal bone**.
- This bone forms part of the skull base and houses structures of the inner and middle ear, a fracture here can create a direct communication between the **subarachnoid space** and the external ear canal.
*Tympanic membrane*
- A rupture of the **tympanic membrane** alone would lead to **otorrhea** (ear discharge), but it would primarily involve blood or middle ear fluid, not CSF.
- While a ruptured tympanic membrane is necessary for CSF to exit the ear canal, the source of the CSF leak itself is proximal to the middle ear.
*Cribriform plate*
- A fracture of the **cribriform plate** typically results in **CSF rhinorrhea** (CSF leakage from the nose), as it is located structurally above the nasal cavity.
- It is not directly involved in CSF leakage from the ear.
*Parietal bone*
- Fractures of the **parietal bone** are typically associated with epidural or subdural hematomas or brain injury, depending on the extent of the trauma.
- They are not a usual cause of CSF leakage from the ear since this bone does not contain CSF pathways that directly communicate with the ear.
Complications of Skull Base Surgery Indian Medical PG Question 7: Which of the following is most specific for CSF in rhinorrhea?
- A. Albumin
- B. Macroglobulin
- C. Beta-2 transferrin (Correct Answer)
- D. Beta-2 microglobulin
Complications of Skull Base Surgery Explanation: ***b-2 transferrin***
- **Beta-2 transferrin** is a desialylated form of transferrin found almost exclusively in **cerebrospinal fluid (CSF)**, perilymph, and aqueous humor.
- Its presence in nasal discharge is highly **specific** for the diagnosis of CSF rhinorrhea, as it is not typically found in serum or other bodily secretions.
*Albumin*
- **Albumin** is abundant in both serum and CSF, so its presence in nasal discharge is not specific for CSF and could indicate the presence of blood or inflammatory exudates.
- Measuring albumin levels alone would not reliably differentiate CSF rhinorrhea from other types of nasal discharge.
*Macroglobulin*
- **Alpha-2 macroglobulin** is a large plasma protein primarily found in **blood**, not typically in significant concentrations in CSF.
- Its presence would be more indicative of serum contamination rather than CSF leakage.
*b-2 microglobulin*
- **Beta-2 microglobulin** is a protein found on the surface of most nucleated cells and is present in various body fluids including **serum** and **CSF**, though usually in higher concentrations in conditions associated with inflammation or malignancy.
- While present in CSF, it is not specific enough to reliably distinguish CSF rhinorrhea from other types of nasal discharge, especially if blood is also present.
Complications of Skull Base Surgery Indian Medical PG Question 8: Least common complication of a fall from height is -
- A. Fracture fibula (Correct Answer)
- B. Fracture base of skull
- C. Fracture 12th thoracic vertebra
- D. Fracture calcaneum
Complications of Skull Base Surgery Explanation: ***Fracture fibula***
- A fibula fracture is the **least common** with a fall from height because the force is typically axial, impacting the lower limbs.
- The fibula is a **non-weight-bearing bone**, making it less susceptible to direct axial compression trauma from a fall.
*Fracture base of skull*
- **Basilar skull fractures** can occur from significant head trauma in a fall, especially when the head strikes a surface.
- While not as common as extremity fractures, they are a serious and known complication of falls from height.
*Fracture 12th thoracic vertebra*
- **Vertebral compression fractures**, particularly in the thoracolumbar region (like T12), are common due to axial loading upon landing on the buttocks or feet.
- This is a frequent injury in falls from height due to the **compressive forces** transmitted through the spine.
*Fracture calcaneum*
- **Heel bone fractures** (calcaneum) are very common in falls from height, as direct impact often occurs on the feet.
- The calcaneus bears the initial and substantial impact, making it highly vulnerable to **crush injuries** in such falls.
Complications of Skull Base Surgery Indian Medical PG Question 9: The complication which will not occur after PCNL surgery:
- A. Organ injury
- B. Urethral stricture (Correct Answer)
- C. Bleeding
- D. Sepsis
Complications of Skull Base Surgery Explanation: ***Urethral stricture***
- **Urethral stricture** is a complication typically associated with transurethral procedures involving instrumentation through the urethra, such as a **Transurethral Resection of the Prostate (TURP)** or repeated urethral catheterisation.
- **PCNL (Percutaneous Nephrolithotomy)** involves direct access to the kidney through the skin in the flank, bypassing the urethra entirely, therefore, making urethral stricture not a direct complication of this procedure.
*Organ injury*
- **Organ injury**, particularly to adjacent organs like the **colon**, **pleura**, or **spleen/liver**, can occur during PCNL if the access tract is misdirected or during instrumentation.
- This is a well-recognised but infrequent complication requiring careful pre-operative planning and imaging guidance.
*Bleeding*
- **Bleeding** is a common complication of PCNL due to the invasive nature of the procedure, involving puncture of the kidney and fragmentation of stones.
- It can range from minor self-limiting bleeding to significant haemorrhage requiring transfusion or further intervention such as **angiography** and **embolization**.
*Sepsis*
- **Sepsis** is a serious potential complication, particularly if the patient has pre-existing urinary tract infection or if bacteria are dislodged during stone fragmentation.
- **Infection** can disseminate into the bloodstream, leading to severe systemic inflammatory response syndrome and septic shock.
Complications of Skull Base Surgery Indian Medical PG Question 10: What is the most common space-occupying lesion in the cerebellopontine angle?
- A. Meningioma
- B. Glioma
- C. Neurofibroma
- D. Acoustic neuroma (Correct Answer)
Complications of Skull Base Surgery Explanation: **Explanation:**
The **Cerebellopontine Angle (CPA)** is a potential space in the posterior cranial fossa. The correct answer is **Acoustic Neuroma** (also known as Vestibular Schwannoma), which accounts for approximately **80–85%** of all CPA tumors.
1. **Acoustic Neuroma (Correct):** These are benign, slow-growing tumors arising from the Schwann cells of the vestibular nerve (most commonly the inferior vestibular nerve). They typically present with unilateral sensorineural hearing loss, tinnitus, and dysequilibrium.
2. **Meningioma (Incorrect):** This is the **second most common** CPA lesion, accounting for about 10–15% of cases. Unlike acoustic neuromas, they often do not widen the internal auditory canal (IAC) and may show calcification or a "dural tail" on MRI.
3. **Epidermoid Cyst (Incorrect):** These are the third most common CPA lesions (approx. 5%). They are congenital and characterized by a "pearly" appearance and restricted diffusion on MRI.
4. **Neurofibroma (Incorrect):** While associated with Neurofibromatosis Type 1, the tumors in the CPA (specifically in NF-2) are actually **Schwannomas**, not neurofibromas.
5. **Glioma (Incorrect):** These are primary brain parenchyma tumors (e.g., brainstem gliomas) and are rarely primary occupants of the CPA space.
**NEET-PG High-Yield Pearls:**
* **Gold Standard Investigation:** Contrast-enhanced MRI (Gadolinium) is the investigation of choice.
* **Bilateral Acoustic Neuromas:** Pathognomonic for **Neurofibromatosis Type 2 (NF-2)**.
* **Audiometry Finding:** Characterized by "Retrocochlear" pathology (Poor speech discrimination score out of proportion to pure tone loss and absence of recruitment).
* **Order of Frequency in CPA:** Acoustic Neuroma > Meningioma > Epidermoid > Facial Nerve Schwannoma.
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