Complications of rhinosinusitis

• Direct extension through thin bone, especially the lamina papyracea and frontal sinus walls
• Osteitis/osteomyelitis
• Retrograde septic thrombophlebitis through valveless diploic veins of Breschet to orbital and intracranial venous channels
  K. J. Lee’s Essential Otolaryngology, p. 540; Scott-Brown's Otorhinolaryngology Head & Neck Surgery, Vol. 1, p. 1161.

1. Orbital complications

2. Intracranial complications

• Meningitis
• Cerebritis
• Epidural (extradural) abscess/empyema
• Subdural empyema: the most common intracranial complication of sinusitis; may cause fever, headache, seizures, focal neurologic deficits, meningeal irritation, and rapid deterioration.
• Intracerebral abscess/brain abscess, commonly frontal-lobe related
• Cerebral venous sinus thrombosis, including cavernous or superior sagittal sinus thrombosis
• Rarely, cerebral ischemia/infarction from venous thrombosis or cavernous carotid involvement

3. Osseous complications

• Frontal bone osteomyelitis
• Pott's puffy tumour: frontal bone osteomyelitis with a subperiosteal abscess, presenting as a doughy/boggy forehead swelling
• Osteitis or osteomyelitis of other sinus walls, less commonly

4. Chronic or expansile complications

• Mucocele
• Pyocele: infected mucocele
• Bony expansion/erosion with extension into the orbit or anterior cranial fossa
• Orbital displacement, diplopia, proptosis, optic neuropathy, and intracranial extension in advanced cases

High-yield sinus-to-complication associations

One-line exam summary

Recent guidance for orbital complications of rhinosinusitis

Core management approach

1. Treat orbital cellulitis as an emergency
   • Admit to hospital.
   • Obtain urgent ENT and ophthalmology assessment.
   • Perform baseline and serial examination: visual acuity, color vision, pupils for RAPD, ocular movements, proptosis, chemosis, and fundus where possible.
   • Repeat eye assessments at least twice daily, or every 4-6 hours if concern is increasing.
     Scott-Brown's Otorhinolaryngology Head & Neck Surgery, Vol. 1, p. 1163.
2. Image when postseptal disease or abscess is suspected
   • Contrast-enhanced CT of orbits and paranasal sinuses is first-line when there is ophthalmoplegia, pain on eye movement, proptosis, visual impairment, suspected abscess, failure to improve, or planned drainage.
   • Add MRI brain/orbits with venography if intracranial extension, cavernous sinus thrombosis, cerebritis, or venous thrombosis is suspected. CT can miss early intracranial disease.
     Scott-Brown's Otorhinolaryngology Head & Neck Surgery, Vol. 1, pp. 1163-1164.
3. Start empiric IV broad-spectrum antibiotics promptly
   • Cover common sinus pathogens, including streptococci, S. aureus, anaerobes, and, according to local epidemiology, MRSA.
   • The current RCH pediatric pathway uses a third-generation cephalosporin, with vancomycin added when MRSA is suspected, followed by oral amoxicillin-clavulanate once clearly improving. It suggests at least 3-4 days of IV treatment and a total treatment course of roughly 10-14 days, adjusted for clinical response and microbiology.
   • Antibiotic selection must follow local resistance data, allergy history, culture results, age, renal function, and whether there is dental or fungal disease. See the RCH antibiotic pathway.
4. Drain urgently when vision or infection control is threatened Immediate surgical drainage plus sinus source control is indicated with:
   • Reduced visual acuity, impaired color vision, RAPD, or optic neuropathy
   • Orbital abscess
   • Large or non-medial subperiosteal abscess, especially superior/lateral abscess
   • Worsening proptosis, ophthalmoplegia, rising intraorbital pressure, or corneal exposure
   • Clinical deterioration or inadequate improvement after initial IV therapy
   • Associated intracranial complication
   • Suspected invasive fungal rhinosinusitis
   Endoscopic sinus drainage is commonly used for medial subperiosteal collections and ethmoid disease. Combined endonasal and orbital approaches may be needed depending on abscess location. K. J. Lee’s Essential Otolaryngology, p. 541; Scott-Brown's Otorhinolaryngology Head & Neck Surgery, Vol. 1, pp. 1165-1168.
5. Do not manage cavernous sinus thrombosis as routine orbital cellulitis
   • It requires ICU-level multidisciplinary care involving ENT, ophthalmology, infectious diseases, neurology/neurosurgery, and radiology.
   • Obtain MRI/MR venography, treat with IV antibiotics, drain the sinonasal source where indicated, and assess for intracranial complications.
   • Anticoagulation remains individualized because evidence and practice vary.
     K. J. Lee’s Essential Otolaryngology, p. 541.

Practical surgical-risk stratification

Corticosteroids

Recent sources

• The current RCH clinical guideline provides a practical pediatric admission, imaging, antibiotic, and escalation pathway.
• Luk and Rose, 2025, PMID: 41059999, emphasizes imaging, ophthalmic findings, abscess features, and progression despite antibiotics as determinants of surgery.
• Welkoborsky et al., 2022, PMID: 34874263, supports inpatient interdisciplinary care, broad-spectrum antibiotics, and endonasal drainage for severe disease or abscess.
• The 2025 Italian pediatric sinusitis consensus is recent but is mainly for acute bacterial sinusitis rather than a detailed orbital-complication protocol: Venturini et al., 2025, PMID: 40140854.

A. Emergency lateral canthotomy and inferior cantholysis

Indications

• Rapidly progressive proptosis with a tense orbit
• Reduced visual acuity or color vision
• Relative afferent pupillary defect
• Markedly elevated intraocular pressure
• Ophthalmoplegia or severe pain on eye movement
• Optic nerve compromise from hematoma, abscess, emphysema, or severe orbital cellulitis

Steps

1. Call for ophthalmology and ENT support, while simultaneously preparing for decompression. Begin treatment of the cause, such as IV antibiotics for orbital cellulitis or control of bleeding for retrobulbar hemorrhage.
2. Assess and document baseline eye status where possible:
   • Visual acuity and color vision
   • Pupillary response and RAPD
   • Ocular motility
   • Proptosis and globe tension
   • Intraocular pressure, if it does not delay intervention
3. Provide analgesia, anxiolysis, and local anesthesia if the clinical situation permits. Prepare sterile field and protect the globe.
4. Make a lateral canthotomy:
   • Apply a hemostat briefly at the lateral canthus to mark the site and aid hemostasis.
   • Make a full-thickness horizontal incision from the lateral canthal angle toward the lateral orbital rim.
5. Perform inferior cantholysis:
   • Retract the lower eyelid away from the globe.
   • Identify the inferior crus of the lateral canthal tendon by gentle palpation or "strumming."
   • Divide the inferior crus to free the lower lid and permit anterior displacement of the globe and orbital contents.
6. Immediately reassess:
   • Reduction in orbital tension and proptosis
   • Intraocular pressure
   • Vision, pupils, color vision, and ocular movements
7. If decompression remains inadequate, divide the superior crus of the lateral canthal tendon, usually with ophthalmology involvement. Persistent compromise may require urgent orbitotomy, abscess drainage, or bony orbital decompression.

B. Definitive decompression in sinogenic orbital disease

1. Admission, IV broad-spectrum antibiotics, and urgent ENT-ophthalmology management.
2. Contrast CT of the orbits and paranasal sinuses, unless immediate decompression for vision loss must precede imaging.
3. Endoscopic opening and drainage of the involved sinus, often ethmoidectomy for a medial subperiosteal abscess.
4. Drainage of the orbital collection, endonasally for many medial collections or via an external orbitotomy for lateral/superior or inaccessible collections.
5. Repeat ophthalmic examinations and escalation for residual/recurrent collection or intracranial disease.

C. Endoscopic bony orbital decompression: operative outline

1. General anesthesia and image-guided navigation.
2. Endoscopic nasal access with uncinectomy, maxillary antrostomy, ethmoidectomy, and sphenoidotomy as required for exposure.
3. Identify the lamina papyracea and orbital apex safely.
4. Remove the medial orbital wall and, when needed, the medial portion of the orbital floor.
5. Carefully incise the periorbita to permit controlled prolapse of orbital fat into the ethmoid cavity.
6. Preserve the inferomedial strut and/or an orbital-periosteal sling when possible to reduce postoperative diplopia, unless maximal decompression is necessary for threatened vision.
7. Confirm hemostasis and absence of orbital injury, then perform postoperative visual monitoring.