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OP2.1-8 | Lids, Adnexa and Orbit — Graded Quiz
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A 6-year-old girl has had watering from the right eye since age 3 months. Crigler's massage was performed consistently for 12 months without resolution. At 18 months, lacrimal probing under general anaesthesia was performed but the child still has epiphora at age 6. Which is the most appropriate definitive management at this stage?
Correct. At age 6 with failed conservative management and failed probing, DCR is the definitive procedure. It creates a direct fistula from the lacrimal sac to the nasal mucosa, bypassing the NLD obstruction entirely.
The management ladder for congenital nasolacrimal duct obstruction is: Crigler's massage (first 12-13 months) → probing under GA (if massage fails, done 12-18 months) → probing with silicone intubation (if simple probing fails) → dacryocystorhinostomy (if all else fails, for children over 4-5 years). At age 6 with failed massage and failed probing, DCR is the appropriate definitive surgical procedure. DCR creates a new bony ostium into the nose, bypassing the obstructed nasolacrimal duct.
Crigler's massage is ineffective beyond 12-13 months and certainly not at age 6. Repeat simple probing is unlikely to succeed after failed probing. Silicone intubation is a step between probing and DCR; however, at age 6 with already failed probing, DCR is the appropriate next escalation. Topical steroids have no role in mechanical NLD obstruction.
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A patient with thyroid eye disease is noted to have: lid retraction of 3 mm in the right eye, bilateral periorbital oedema, chemosis, right proptosis of 22 mm (left 17 mm) on Hertel exophthalmometry, and a clinical activity score (CAS) of 2/7. She has been on systemic immunosuppression for 8 months, and the CAS has been stable at 2 or less for 6 months. She requests cosmetic improvement of her proptosis. What is the appropriate next step in management?
Correct. Disease inactive (CAS 2 for 6 months) = surgical rehabilitation can begin. Decompression is first in the sequence. Adding more immunosuppression is not indicated for inactive disease. Lid surgery must always come last in the sequence (after decompression has stabilised the orbital volume and after strabismus is corrected).
In thyroid eye disease, the rehabilitation surgery sequence is: (1) orbital decompression (for proptosis/optic nerve compression), then (2) strabismus surgery (for diplopia), then (3) lid surgery (for lid retraction/lagophthalmos). Surgery is only performed when disease is inactive (CAS <3) for at least 6 months. This patient meets criteria: CAS 2 for 6 months. The appropriate next step is orbital decompression. Lid surgery must come last — decompression and strabismus surgery alter the position of orbital contents and muscle tensions, which changes the lid position.
The rehabilitation sequence in TED is fixed: decompression first, strabismus second, lid surgery last. Performing lid surgery before decompression is incorrect — subsequent decompression changes orbital anatomy and will alter lid position. Once disease is inactive for 6 months, continued observation without intervention is unnecessary. Additional immunosuppression is not indicated for inactive disease.
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A patient with right orbital cellulitis is admitted and started on IV antibiotics. The next morning, his Snellen visual acuity in the right eye has fallen from 6/9 to 6/36 and he reports that red looks 'dull' in that eye. CT orbit shows a subperiosteal abscess. Chandler classification is Grade III. What is the immediate management?
Correct. Falling visual acuity and colour desaturation = optic nerve compromise — this is the absolute surgical trigger. A confirmed subperiosteal abscess plus vision deterioration requires immediate surgical drainage. Continuing IV antibiotics alone when vision is deteriorating and abscess is present is inadequate and risks permanent blindness.
In orbital cellulitis, any deterioration in visual acuity or colour vision is an absolute indication for immediate surgical intervention regardless of the Chandler stage. This patient has confirmed vision loss (6/36, down from 6/9) and colour desaturation, indicating optic nerve compromise. The subperiosteal abscess (Chandler Grade III) confirmed on CT requires urgent surgical drainage. The cardinal rule: monitor visual acuity and colour vision at least every 12 hours — vision change demands immediate action and overrides all other management steps.
Vision deterioration overrides antibiotic wait-and-see in orbital cellulitis. Once visual acuity has fallen and colour desaturation is present alongside a confirmed CT abscess, surgical drainage cannot be deferred. Oral antibiotics and outpatient management are appropriate only for preseptal cellulitis. The decision trigger for surgery in orbital cellulitis is: (1) no improvement on IV antibiotics after 24-48 hours, (2) vision deterioration, (3) CT-confirmed abscess — any of these mandates surgery.
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A patient with suspected cavernous sinus thrombosis presents with sepsis, bilateral proptosis, bilateral ophthalmoplegia, and bilateral periorbital oedema following a dental abscess. Blood cultures have been drawn. What is the sequence of immediate management?
Correct. Start IV antibiotics immediately after blood cultures are drawn — do not wait for culture results when sepsis is present. Anticoagulation after senior review, urgent MRI/MRV, and multidisciplinary team involvement (ophthalmology, neurology, neurosurgery, ENT, ICU) are the components of management. The cavernous sinus cannot be directly drained surgically.
Cavernous sinus thrombosis management is a multidisciplinary emergency. Once blood cultures are drawn, IV antibiotics must be started immediately (never wait for culture results). Antibiotic choice covers the likely organisms: Staphylococcus aureus (dental/facial source), Streptococcus, and anaerobes — IV vancomycin or flucloxacillin plus metronidazole is typical. Anticoagulation with LMWH is used in septic CST after multidisciplinary review (reduces extension of thrombosis and mortality, though evidence remains debated). Imaging (MRI with MRV) confirms the diagnosis and identifies complications. The cavernous sinus is not directly surgically accessible; treatment of the primary source (dental drainage) is performed when feasible.
Delaying antibiotics to await culture results in sepsis is dangerous. Fungal CST (typically Mucor in immunocompromised or diabetic patients) is a separate entity and not the most common cause. The cavernous sinus cannot be directly accessed surgically. LMWH anticoagulation in septic CST is supported by evidence (reduces propagation of thrombosis) but requires senior clinician decision-making and is not a blanket first step.
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A 4-year-old girl presents with rapidly progressive right proptosis over 4 weeks. On examination, the right globe is displaced inferolaterally, there is a palpable firm mass in the right superolateral orbit, and there is no warmth or fever. CT orbit shows a well-circumscribed, round, hypo-attenuating lesion at the right zygomaticofrontal suture. What is the most likely diagnosis?
Correct. Superolateral mass at the zygomaticofrontal suture in a child, with low-attenuation content on CT = dermoid cyst. This is the classic location. The 4-week time course, though relatively rapid for a dermoid, combined with the CT location and appearance distinguishes it from rhabdomyosarcoma.
Dermoid cysts are the commonest orbital tumours in children overall (though rhabdomyosarcoma is the commonest malignant). They arise from epithelial remnants trapped at bony suture lines during embryological development. The zygomaticofrontal suture (superolateral orbit) is the most common site, presenting as a firm, non-tender, slowly or moderately growing mass at the orbital rim that may erode adjacent bone. CT shows a well-defined, low-attenuation (fat-containing) lesion at or near the suture line. The differential from rhabdomyosarcoma is the slower time course (weeks-months vs days-weeks) and the characteristic suture-line location.
Rhabdomyosarcoma has a more rapidly destructive course, often infiltrating orbital fat, with no predilection for suture lines. The key discriminator for dermoid is the location at a bony suture (zygomaticofrontal suture = superolateral) and low-attenuation (fat) content on CT. Orbital cellulitis is an infection, not a mass lesion, and presents with inflammatory signs and systemic features. Lacrimal gland ductal cysts are not at the suture and do not contain fat.
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A 52-year-old man with no known systemic illness presents with progressive right proptosis over 3 months. Examination reveals the right eye is displaced downward and outward. CT orbit shows a superior orbital mass that extends through the orbital roof into the skull. What investigation is most essential before planning definitive management?
Correct. A malignant orbital mass with bony and skull involvement requires tissue diagnosis (biopsy) and complete systemic staging before management decisions. Meningioma, metastasis, and lymphoma must all be considered. Staging guides whether surgery, radiotherapy, chemotherapy, or combined treatment is appropriate.
An orbital mass with skull base extension is highly suspicious for a malignant tumour (secondary orbital involvement from intracranial meningioma, metastasis, or primary orbital malignancy). The essential steps before management planning are: (1) tissue diagnosis via biopsy and (2) systemic staging (CT chest-abdomen-pelvis, bone scan, relevant tumour markers). Staging determines whether the disease is local, locoregional, or metastatic, which fundamentally alters the management approach. Watchful waiting with steroids is inappropriate for a potentially malignant mass with skull base involvement. Thyroid eye disease does not invade bone.
Chest X-ray alone is insufficient staging. Thyroid eye disease does not cause bony destruction. Topical steroids and watchful waiting are inappropriate for a mass with skull base invasion. Tissue diagnosis plus complete systemic staging is mandatory before any orbital tumour with aggressive features is managed — incomplete staging risks undertreating systemic disease.
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A 70-year-old man presents with a 6-month history of bilateral periorbital oedema, bilateral proptosis, and diplopia. CT orbit shows bilateral diffuse infiltration of the orbital fat, moulding around the globe without bony destruction. Biopsy shows lymphoid tissue with immunohistochemistry consistent with low-grade B-cell lymphoma. What is the most appropriate management?
Correct. Orbital lymphoma management: (1) tissue diagnosis confirmed, (2) systemic staging mandatory (20-30% have systemic involvement), (3) treatment = low-dose radiotherapy for localised disease or systemic chemotherapy for systemic involvement. Haematology referral is required.
Orbital lymphoma is the most common orbital malignancy in the elderly. Most are low-grade B-cell (MALT) lymphomas. The CT appearance — diffuse bilateral infiltration moulding around orbital structures ('salmon-patch' subconjunctival lesion clinically) without bony destruction — is characteristic. After tissue diagnosis, full systemic staging (CT body, bone marrow biopsy, haematology referral) is mandatory because 20-30% have concurrent systemic lymphoma. Localised orbital disease is treated with low-dose external beam radiotherapy (excellent local control); systemic disease requires chemotherapy (e.g. R-CHOP). Exenteration is not indicated. Orbital lymphoma is not always benign — some transform to high-grade.
Orbital exenteration is not appropriate for lymphoma, which is a radiation/chemotherapy-sensitive disease. Topical steroids are not treatment for lymphoma. Orbital lymphoma is NOT always benign — low-grade does not mean curable with observation; local progression and potential systemic involvement require treatment. Systemic staging and oncology/haematology referral are essential.
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A 3-year-old boy has been noted to have left-sided ptosis since birth. Examination shows MRD-1 of 0 mm on the left (lid covers the pupil), levator function of 2 mm, and positive Bell's phenomenon. His right MRD-1 is 5 mm. He has been referred for management. What is the primary concern if the ptosis is not corrected, and what surgical procedure should be planned?
Correct. Ptosis covering the visual axis in a 3-year-old = deprivation amblyopia risk — this is the primary clinical concern and mandates early surgical correction. Poor levator function (2 mm) + positive Bell's = frontalis suspension with fascia lata. Early correction (before age 5-6) is essential to prevent permanent amblyopia.
Congenital ptosis with MRD-1 of 0 mm (lid covering the visual axis) creates deprivation amblyopia — the most severe form of amblyopia, because the visual stimulus is completely blocked from the developing retina during the critical period. This must be corrected urgently. With poor levator function (2 mm), frontalis suspension is the appropriate procedure. Fascia lata harvested from the thigh is the preferred material in children over 3 years (autologous, durable). Bell's phenomenon is positive, which means the cornea is protected post-operatively — this is important safety information. Fasanella-Servat (Mullerectomy) is only used for mild ptosis with good levator function, and only reduces lid by 1-2 mm.
Deferring surgery is dangerous when the visual axis is occluded in a child under 7 — deprivation amblyopia develops rapidly and is permanent if untreated. Levator resection requires adequate levator function (>4-5 mm); with only 2 mm levator function, frontalis suspension is required. Fasanella-Servat corrects only 1-2 mm of ptosis and is used for mild ptosis with Muller's muscle involvement. Corneal exposure risk is actually low with positive Bell's phenomenon.
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A 10-year-old child develops left preseptal cellulitis following a mosquito bite. He is started on oral co-amoxiclav. After 48 hours, the left eyelid swelling has worsened and he now has mild fever. The left eye movements are full and vision is 6/6 bilaterally. There is no proptosis. What is the most appropriate next step?
Correct. Preseptal cellulitis not improving after 48 hours of appropriate oral antibiotics requires step-up to IV antibiotics and hospital admission for monitoring. Close monitoring for any development of orbital signs (proptosis, restricted EOM, vision change) is essential during IV therapy.
Preseptal cellulitis not responding to oral antibiotics within 48 hours requires step-up to IV antibiotics and hospital admission. The decision to upgrade is based on clinical progression — worsening swelling and fever despite adequate oral therapy. CT orbit is indicated if there is any sign of orbital involvement (proptosis, restricted/painful EOM, vision change) or if the child deteriorates on IV antibiotics. The absence of proptosis, full ocular movements, and normal vision confirm this is still preseptal, but the failure of oral antibiotics mandates IV step-up. Topical drops are adjunctive and not a substitute for systemic therapy.
Continuing oral antibiotics when preseptal cellulitis is worsening at 48 hours is inadequate — this is a clear indication to step up to IV therapy and admit. CT is not yet indicated while the cellulitis is clearly preseptal (no proptosis, full EOM, normal vision); CT is reserved for suspected orbital involvement or failure to improve on IV antibiotics. Topical drops alone are not treatment for preseptal cellulitis.
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A 65-year-old man with a 2-week history of right-sided pulsatile proptosis attends the eye clinic. On auscultation, a bruit is audible over the right eye. Intraocular pressure in the right eye is 28 mmHg. There is episcleral venous congestion. Which diagnosis does this clinical picture most suggest, and what investigation will confirm it?
Correct. Pulsatile proptosis + bruit + episcleral venous congestion + raised IOP = carotid-cavernous fistula. CT angiography confirms the fistula and identifies whether it is direct (high-flow, post-traumatic) or indirect (dural, spontaneous). Endovascular coil embolisation is the treatment of choice.
The combination of pulsatile proptosis, orbital bruit, episcleral venous congestion, and elevated IOP is the classic presentation of a carotid-cavernous fistula (CCF) — an abnormal communication between the carotid arterial system and the cavernous sinus. Arterialised blood fills the cavernous sinus and drains backwards via the superior ophthalmic vein into the orbit, causing raised episcleral venous pressure (transmitted to IOP), pulsatile proptosis (arterial pulsation transmitted via the distended venous system), and a bruit. CT angiography is the initial investigation; catheter angiography is the gold standard and allows simultaneous endovascular treatment (coil embolisation). Thyroid eye disease does not cause a bruit.
Thyroid eye disease causes non-pulsatile proptosis and no bruit. Lymphoma and rhabdomyosarcoma do not produce pulsatile proptosis or a bruit. The combination of pulsatile proptosis, bruit, and episcleral venous congestion is pathognomonic of a vascular communication between the arterial and venous systems — a carotid-cavernous fistula. Angiography is the definitive investigation.
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