Important differentials

1. Orbital cellulitis or orbital abscess
   • Infection behind the orbital septum, often from sinusitis, a dental source, trauma, or skin infection.
   • Supports: one-sided eyelid/cheek swelling, possible eye displacement or difficulty opening the eye.
   • Ask/examine for: fever, severe eye pain, pain on moving the eye, double vision, reduced vision, red eye/chemosis, protruding eye.
   • Must be urgently ruled out today, because it can threaten vision and spread intracranially. Orbital cellulitis classically causes pain/restriction of eye movement, proptosis, chemosis, or visual impairment, as described in Tintinalli's Emergency Medicine.
2. Preseptal/periorbital cellulitis
   • Infection limited to eyelid and tissues in front of the orbit.
   • Supports: swollen, red, warm, tender eyelid with preserved vision and normal painless eye movements.
   • Less dangerous than orbital cellulitis, but clinical examination and often CT are needed to distinguish it from orbital disease.
3. Sinus-related complication
   • Chronic or acute ethmoid/maxillary sinusitis can cause swelling around an eye, or lead to orbital cellulitis/subperiosteal abscess.
   • Look for blocked nose, purulent nasal discharge, facial pressure, headache, fever, dental pain.
   • CT of the paranasal sinuses and orbit with contrast is appropriate if orbital involvement is possible.
4. Dental infection, facial cellulitis, or deep facial-space infection
   • An upper tooth infection can extend into the cheek, maxilla, sinus, and orbit.
   • Look for toothache, loose/decayed teeth, gum swelling, pain on chewing, trismus, foul taste, fever.
   • Dental and ENT/maxillofacial assessment may be needed urgently.
5. Malignancy involving sinus, orbit, salivary tissue, or nasopharynx
   • The 3-month duration and smoking history make this an important diagnosis to exclude, especially if swelling is persistent, progressive, firm, or painless.
   • Possible cancers include sinonasal carcinoma, lymphoma, orbital tumor, or an invasive facial/skin malignancy.
   • Findings supporting this: unilateral nasal obstruction, recurrent nosebleeds, facial numbness, tooth loosening, progressive eye prominence/double vision, neck nodes, weight loss.
   • Requires contrast CT/MRI of orbit, face, sinuses, and ENT examination with nasal endoscopy. A suspicious mass requires biopsy.
6. Superior vena cava (SVC) syndrome due to intrathoracic malignancy
   • A smoker is at risk of lung cancer. SVC obstruction can cause facial/neck fullness, upper-limb swelling, distended neck/chest veins, cough, breathlessness, and headache. Lung carcinoma and lymphoma are common causes.
   • This is less likely if the swelling is only one-sided around one eye, but must be considered if there is neck/arm swelling or respiratory symptoms. A textbook review notes that SVC obstruction causes facial, neck, and upper-limb swelling, with dyspnea and headache.
   • Rule out with urgent chest examination and contrast CT chest.
7. Allergic angioedema/contact dermatitis
   • More likely if swelling came on quickly, is itchy, non-tender, fluctuates, or follows a medication, food, insect bite, cosmetics, hair dye, or topical product.
   • Three months of progressive unilateral swelling makes this less likely.
   • If tongue/lip swelling, hoarseness, wheezing, or breathing difficulty occurs: emergency care immediately.
8. Thyroid eye disease
   • Can produce eyelid swelling and bulging eyes, often with lid retraction, gritty eyes, double vision, heat intolerance, tremor, palpitations, or weight loss.
   • Usually bilateral, though asymmetric presentation can occur.
   • Rule out with examination for proptosis and thyroid function tests: TSH and free T4, plus orbital imaging if needed.
9. Hypothyroidism (myxedema)
   • Can cause facial/periorbital puffiness, non-pitting edema, dry skin, constipation, fatigue, weight gain, slow pulse, and cold intolerance.
   • Usually bilateral and generalized, not a pronounced one-sided facial process. Still check TSH and free T4 if not already tested.
10. Renal disease/nephrotic syndrome

• Causes periorbital puffiness, often most obvious in the morning, along with leg edema, frothy urine, high blood pressure, proteinuria, and low albumin.
• Usually bilateral. Rule out with urinalysis, urine protein-creatinine ratio, serum creatinine, albumin, and lipid profile.

1. Alcohol-associated liver disease/cirrhosis with hypoalbuminemia

• Chronic alcohol use can cause poor nutrition, low albumin, portal hypertension, ascites, leg swelling, jaundice, easy bruising, and generalized edema.
• It could worsen overall facial puffiness, but it does not adequately explain a major unilateral left periorbital swelling. Therefore it cannot be accepted as the sole explanation without ruling out local orbital, sinus, dental, or malignant disease.
• Evaluate liver panel, albumin, INR/PT, CBC/platelets, bilirubin, renal function, ultrasound abdomen, and assessment for ascites/encephalopathy.

1. Facial venous/lymphatic obstruction

• Local venous thrombosis, lymphatic obstruction, prior surgery/radiation, mass compression, or inflammatory scarring can produce persistent unilateral facial edema.
• CT/MR face-neck with contrast and Doppler/vascular evaluation may be needed depending on examination.

What needs urgent action

Key tests to request urgently

• Full eye examination: visual acuity, pupils, color vision, eye movements, intraocular pressure, proptosis, fundoscopy.
• CBC with differential, CRP/ESR, blood culture if febrile.
• Renal function, electrolytes, glucose.
• Liver panel, albumin, bilirubin, PT/INR, CBC/platelets.
• Urinalysis and urine protein-creatinine ratio.
• TSH and free T4.
• Contrast CT of orbit, paranasal sinuses, and face. MRI orbit/face if tumor, deep soft-tissue disease, cavernous sinus disease, or brain extension is suspected.
• Dental assessment and dental imaging if any upper-teeth disease.
• Contrast CT chest if cough, breathlessness, upper-body/arm swelling, chest-wall veins, weight loss, or other concern for SVC syndrome/lung cancer.
• ENT nasal endoscopy and biopsy if imaging shows a mass.