Orbital Inflammations — MCQs
A young girl with a previous history of repeated pain over the medial canthus and chronic use of decongestants now presents with intense chills, rigors, and diplopia on lateral gaze. Examination shows an optic disc that is congested. The most likely diagnosis would be:
Which fungus is most commonly associated with orbital cellulitis in patients with diabetic ketoacidosis?
A 40F presents with double vision, headaches, and a progressively enlarging thyroid mass. She has proptosis and limited eye movement. TSH is suppressed. Likely cause of her symptoms?
Most common ocular movement affected in thyroid ophthalmopathy:
What is the diagnosis for a patient with unilateral proptosis with bilateral 6th nerve palsy with chemosis and euthyroid status?
A patient presents with proptosis, restriction of eye movements, and is found to be euthyroid. What is the most likely diagnosis?
Bilateral ptosis is seen in all except which of the following?
Chronic granulomatous inflammation in upper lid (painless swelling) is characteristic of:
All are causes of proptosis except:
Enophthalmos can be caused by all of the following EXCEPT:
Orbital Inflammations Indian Medical PG Practice Questions and MCQs
Question 1: A young girl with a previous history of repeated pain over the medial canthus and chronic use of decongestants now presents with intense chills, rigors, and diplopia on lateral gaze. Examination shows an optic disc that is congested. The most likely diagnosis would be:
- A. Orbital Apex Syndrome
- B. Orbital Cellulitis
- C. Ethmoidal Sinusitis
- D. Cavernous Sinus Thrombosis (Correct Answer)
Explanation: ***Cavernous Sinus Thrombosis*** - The combination of **chills**, **rigors**, **diplopia on lateral gaze** (due to abducens nerve palsy), and a **congested optic disc** points strongly to cavernous sinus thrombosis [1]. - A history of recurrent **medial canthus pain** and **decongestant use** suggests underlying sinusitis, which is a common predisposing factor for this thrombotic event [1]. Rigors specifically represent a rapid rise in body temperature often associated with bacterial infection [2]. *Ethmoidal Sinusitis* - While ethmoidal sinusitis can spread to the orbit, it typically presents with **localized pain**, **tenderness**, and **periorbital swelling**, rather than systemic symptoms like chills, rigors, and diplopia indicating cranial nerve involvement. - A **congested optic disc** is more indicative of increased intracranial pressure or orbital congestion, which is a more severe complication than isolated ethmoidal sinusitis [3]. *Orbital Cellulitis* - **Orbital cellulitis** presents with **proptosis**, **ophthalmoplegia**, **eyelid swelling**, and **erythema**, often with fever. While it can cause diplopia, the intense systemic symptoms (rigors) and a congested optic disc are more suggestive of an intracranial rather than purely orbital process. - It does not typically cause the prominent abducens nerve palsy or the systemic severity seen in cavernous sinus thrombosis without direct spread. *Orbital Apex Syndrome* - **Orbital apex syndrome** involves cranial nerves II, III, IV, V1, and VI, leading to **vision loss**, **ophthalmoplegia**, and **facial numbness**. While it includes diplopia and can affect the optic nerve (leading to congestion), the intense systemic symptoms of **chills** and **rigors** (suggesting widespread infection/sepsis) are less characteristic of orbital apex syndrome itself and more indicative of a direct thrombotic or septic process like cavernous sinus thrombosis.
Question 2: Which fungus is most commonly associated with orbital cellulitis in patients with diabetic ketoacidosis?
- A. Candida
- B. Mucor
- C. Rhizopus (Correct Answer)
- D. Aspergillus
Explanation: ***Rhizopus*** - *Rhizopus* is the most common cause of **mucormycosis** (also called zygomycosis), an aggressive fungal infection that frequently affects immunocompromised patients, especially those with **diabetic ketoacidosis (DKA)**. - *Rhizopus arrhizus* (formerly *R. oryzae*) accounts for approximately **70% of all mucormycosis cases**, making it the single most common causative organism. - In DKA, the acidic environment and high glucose levels favor the growth of **Mucorales fungi**, leading to rapid progression from the sinuses to the orbit and brain (rhinoorbital-cerebral mucormycosis). *Candida* - While *Candida* is a common cause of fungal infections, it typically manifests as **candidemia**, **esophagitis**, or **vulvovaginitis**, and is rarely associated with orbital cellulitis in DKA. - *Candida* infections are more likely in patients with indwelling catheters or those on broad-spectrum antibiotics, rather than specifically linked to DKA-induced orbital cellulitis. *Mucor* - The genus *Mucor* is part of the **Mucorales order** and can cause **mucormycosis** with identical clinical presentations to *Rhizopus*. - However, *Mucor* species account for only **10-20% of mucormycosis cases**, making *Rhizopus* the **most commonly** associated genus as asked in the question. - While both are clinically grouped under "mucormycosis," *Rhizopus* is the more specific and statistically correct answer when identifying the most common causative fungus. *Aspergillus* - *Aspergillus* species are common environmental fungi that can cause invasive infections, particularly in immunocompromised patients, leading to conditions like **aspergilloma** or **invasive aspergillosis**. - While *Aspergillus* can cause sinus and orbital infections, it is less commonly associated with the rapid, aggressive form of orbital cellulitis seen in DKA compared to mucormycosis caused by *Rhizopus*.
Question 3: A 40F presents with double vision, headaches, and a progressively enlarging thyroid mass. She has proptosis and limited eye movement. TSH is suppressed. Likely cause of her symptoms?
- A. Pituitary adenoma
- B. Orbital cellulitis
- C. Graves' orbitopathy (Correct Answer)
- D. Thyroid carcinoma
Explanation: Graves' orbitopathy - The combination of **proptosis**, **limited eye movement (ophthalmoplegia)** causing double vision, and a suppressed TSH (indicating hyperthyroidism) is highly characteristic of **Graves' disease** with orbital involvement [1]. - An **enlarging thyroid mass** further supports Graves' disease, as it often presents with goiter and hyperthyroidism, leading to the autoimmune sequelae in the orbit [1]. *Pituitary adenoma* - While it can cause **headaches** and **double vision** due to oculomotor nerve compression, a pituitary adenoma would not typically cause a progressively **enlarging thyroid mass** or **proptosis** with suppressed TSH. - Hypersecreting pituitary adenomas (e.g., ACTH, GH) affect other endocrine axes, and non-secreting ones primarily cause mass effect. *Orbital cellulitis* - This is an **acute infection** of the orbital tissues, usually presenting with **pain, fever, rapidly progressing proptosis**, and erythema, which is not suggested by the chronic and progressive nature of this patient's symptoms. - It would not be associated with a suppressed TSH or an enlarged thyroid gland. *Thyroid carcinoma* - A thyroid carcinoma can present as an **enlarging thyroid mass** and may cause local symptoms like dysphagia or hoarseness if advanced, but it does not directly cause **proptosis**, **double vision**, or suppressed TSH. - Although some rare thyroid cancers can metastasize to the orbit, primary presentation with bilateral proptosis and ophthalmoplegia is not typical.
Question 4: Most common ocular movement affected in thyroid ophthalmopathy:
- A. Elevation (Correct Answer)
- B. Adduction
- C. Abduction
- D. Depression
Explanation: ***Elevation*** - **Restrictive myopathy** of the **inferior rectus muscle** is the most common cause of impaired eye elevation in thyroid ophthalmopathy. - This typically leads to **diplopia** on upward gaze, known as **Graves' ophthalmopathy**. - The inferior rectus is the **most frequently affected** muscle, followed by medial rectus, superior rectus, and lateral rectus (mnemonic: "I'M SLow"). *Adduction* - Impaired adduction (inward movement) is less common and usually associated with **medial rectus restriction**. - While it can occur (second most common muscle involvement), it is not the most frequent manifestation of thyroid ophthalmopathy. *Abduction* - Impaired abduction (outward movement) suggests **lateral rectus involvement**, which is the least common in thyroid ophthalmopathy. - **Sixth nerve palsy** would also cause impaired abduction but is not typically directly caused by thyroid ophthalmopathy. *Depression* - Impaired depression (downward movement) is uncommon in thyroid ophthalmopathy. - Depression is primarily controlled by the **inferior rectus** (which is commonly affected but causes elevation problems, not depression problems) and inferior oblique. - Superior rectus involvement would cause impaired elevation, not depression.
Question 5: What is the diagnosis for a patient with unilateral proptosis with bilateral 6th nerve palsy with chemosis and euthyroid status?
- A. Retinoblastoma
- B. Thyroid ophthalmopathy
- C. Cavernous sinus thrombosis (Correct Answer)
- D. Orbital pseudotumour
Explanation: ***Cavernous sinus thrombosis*** - The combination of **unilateral proptosis**, **bilateral 6th nerve palsy**, and **chemosis** strongly suggests cavernous sinus thrombosis. - The cavernous sinus contains cranial nerves III, IV, V1, V2, and VI; thrombosis can lead to dysfunction of these nerves, particularly the **abducens nerve (VI)**, and venous congestion causing proptosis and chemosis. *Retinoblastoma* - Typically presents in **children** with **leukocoria**, strabismus, and sometimes proptosis. - It is a primary intraocular tumor and does not usually cause acute bilateral cranial nerve palsies and chemosis. *Thyroid ophthalmopathy* - Characterized by proptosis, lid retraction, and ophthalmoplegia, often with chemosis and conjunctival injection, but usually in the context of thyroid dysfunction (hyperthyroidism). - While it can cause proptosis, the presence of **bilateral 6th nerve palsy** and a **euthyroid** status makes cavernous sinus thrombosis more likely, as thyroid ophthalmopathy typically presents with restrictive ophthalmoplegia rather than isolated cranial nerve palsies. *Orbital pseudotumour* - Presents with painful proptosis, chemosis, and ophthalmoplegia, which can be unilateral or bilateral. - Differentiating features include a good response to **steroids** and usually **no associated cranial nerve palsies** in the pattern described.
Question 6: A patient presents with proptosis, restriction of eye movements, and is found to be euthyroid. What is the most likely diagnosis?
- A. Orbital cellulitis
- B. Orbital lymphoma
- C. Orbital pseudotumor (Correct Answer)
- D. Thyroid eye disease
Explanation: ***Orbital pseudotumor*** - **Orbital pseudotumor** (also known as idiopathic orbital inflammation) presents with **proptosis** and **restriction of eye movements**. - Typically presents with **acute or subacute onset** of **painful** ophthalmoplegia and proptosis. - It is a **diagnosis of exclusion** after ruling out other causes of orbital inflammation, including thyroid eye disease, orbital cellulitis, and orbital neoplasms. - **Euthyroid status** does not exclude this diagnosis, and it is the **most common painful orbital mass** in adults. *Orbital cellulitis* - **Orbital cellulitis** presents with **rapid onset** of **painful proptosis**, **chemosis**, **ophthalmoplegia**, and signs of **acute infection** (fever, periorbital erythema, recent sinusitis). - The absence of infectious signs and acute inflammatory markers makes this less likely. *Orbital lymphoma* - **Orbital lymphoma** typically presents with **slowly progressive, painless proptosis** in older patients. - It is a **chronic, indolent process** and less likely to cause acute, painful restriction of eye movements. - Usually presents as a palpable mass in the superotemporal orbit. *Thyroid eye disease* - **Thyroid eye disease** (Graves' ophthalmopathy) commonly causes **proptosis** and **restricted eye movements** due to extraocular muscle enlargement. - While **90% of TED patients have hyperthyroidism**, approximately **5% are euthyroid at presentation** (euthyroid Graves' ophthalmopathy). - However, TED typically has a **subacute to chronic onset**, bilateral involvement, lid retraction, and characteristic imaging findings (muscle belly enlargement sparing tendons). - The clinical presentation with acute symptoms and euthyroid state makes **orbital pseudotumor more likely** as the initial diagnosis.
Question 7: Bilateral ptosis is seen in all except which of the following?
- A. Trauma
- B. Hyperthyroidism (Graves' disease) (Correct Answer)
- C. Congenital
- D. Myotonic dystrophy
Explanation: ***Hyperthyroidism (Graves' disease)*** - **Hyperthyroidism** causes eyelid retraction, leading to a **stare** or **lid lag**, rather than **ptosis**. - **Graves' ophthalmopathy** can cause proptosis (bulging eyes) and conjunctival injection, but does not typically manifest as ptosis. *Congenital* - **Congenital ptosis** is often present at birth due to improper development of the **levator palpebrae superioris muscle**. - It can be **bilateral** and is usually isolated, without other systemic symptoms. *Trauma* - **Traumatic ptosis** can occur if the **levator muscle**, **aponeurosis**, or **third cranial nerve** is damaged. - This can be **bilateral** depending on the nature and extent of the head trauma. *Myotonic dystrophy* - **Myotonic dystrophy** is a **hereditary muscle disorder** characterized by progressive muscle weakness. - **Bilateral ptosis** is a very common early sign of **myotonic dystrophy**, often accompanied by **facial weakness** and **myotonia**.
Question 8: Chronic granulomatous inflammation in upper lid (painless swelling) is characteristic of:
- A. Chalazion (Correct Answer)
- B. Trachoma
- C. Internal Hordeolum
- D. External Hordeolum
Explanation: ***Chalazion*** - A chalazion is a **chronic**, sterile, **lipogranulomatous** inflammation of the **meibomian glands**. - It presents as a **painless**, firm, round swelling in the eyelid, often in the upper lid due to the larger meibomian glands. *Trachoma* - Trachoma is a **chronic keratoconjunctivitis** caused by *Chlamydia trachomatis*. - It primarily affects the conjunctiva and cornea, leading to scarring, entropion, and eventual blindness, not a painless eyelid swelling. *Internal Hordeolum* - An internal hordeolum is an **acute** bacterial infection of a **meibomian gland**, forming an abscess. - It is typically **painful**, red, and tender, contrasting with the painless nature of the given presentation. *External hordeolum* - An external hordeolum (stye) is an **acute** bacterial infection of the **glands of Zeis or Moll** at the lid margin. - It is usually **painful**, red, and tender, presenting as a small pustule or nodule on the eyelid margin, not a deep-seated painless swelling.
Question 9: All are causes of proptosis except:
- A. Orbital cellulitis
- B. Orbital tumor
- C. Retinal detachment (Correct Answer)
- D. Graves' disease
Explanation: ***Retinal detachment*** - **Retinal detachment** is a condition where the retina separates from the underlying supportive tissue and does not cause proptosis. - Its primary symptoms include **flashes of light**, **floaters**, and a **curtain-like shadow** in the visual field. *Orbital cellulitis* - **Orbital cellulitis** is an infection of the fat and muscles around the eye, leading to inflammation and swelling. - This swelling can push the eye forward, causing **proptosis**. *Orbital tumor* - An **orbital tumor** is a mass growing within the orbit (eye socket), which occupies space and displaces the eyeball. - This displacement typically results in **proptosis**, often unilateral and progressive. *Graves' disease* - **Graves' disease** (or Graves' ophthalmopathy) involves inflammation and swelling of the extraocular muscles and orbital fat due to autoimmune processes. - This increased volume within the orbit directly causes **proptosis** and is often bilateral.
Question 10: Enophthalmos can be caused by all of the following EXCEPT:
- A. Orbital floor fracture
- B. Loss of orbital fat
- C. Horner's syndrome (Correct Answer)
- D. Cicatricial changes
Explanation: ***Horner's syndrome*** - **Horner's syndrome** is characterized by **ptosis**, **miosis**, and **anhidrosis** on the affected side. - While it can manifest with a mild degree of **apparent enophthalmos**, this is primarily due to the **ptosis creating an illusion** of globe retraction and **not true enophthalmos**. - It is caused by disruption of the **sympathetic nervous supply**, not by actual posterior displacement of the globe. *Cicatricial changes* - **Cicatricial changes** (scarring) within the orbit can cause **traction on the globe**, pulling it inward and resulting in **true enophthalmos**. - This scarring can occur following **trauma**, **inflammation**, or **surgery** affecting the orbital tissues. *Orbital floor fracture* - An **orbital floor fracture** typically leads to **enophthalmos** due to **herniation of orbital contents** (fat, muscle) into the maxillary sinus. - This involves a **structural defect** with increased orbital volume and loss of support for the globe. *Loss of orbital fat* - **Loss of orbital fat**, often seen in conditions like **Romberg's disease**, severe dehydration, or aging, causes the globe to sink backward. - This is due to a **reduction in volume supporting the globe**, resulting in **true enophthalmos**.
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