Cavernous sinus thrombosis is a rare and serious condition caused by infection or trauma that leads to thrombosis of the cavernous sinus. The cavernous sinus is located on either side of the body of the sphenoid bone and contains several cranial nerves and the internal carotid artery. Common causes include sinusitis that spreads through veins. Symptoms include sepsis, venous obstruction leading to proptosis and eye swelling, and cranial nerve palsies. Diagnosis involves imaging like CT or MRI showing enlargement of the sinus. Treatment requires long-term intravenous antibiotics, anticoagulation to prevent spread of clots, and sometimes steroids. Despite aggressive treatment, mortality remains high at 30% and over 40% of

1. Cavernous Sinus Thrombosis
PRESENTED BY –
Dr.ANKITA RAJ (MDS Reader)
Oral & Maxillofacial Surgery Department
Rama Dental College, Kanpur

2. Anatomy of cavernous sinus

3. • Paired venous sinus, on
either side of body of
sphenoid.
• 2cm in length
height of 1cm
• Traversed by numerous
trabeculae, dividing it into
several caverns (spaces)
hence cavernous.

4. • Relations:
– Medial – pituitary above, sphenoidal air cell below
– Lateral – temporal lobe, uncus
– Anterior - superior orbital fissure
– Posterior - petrous apex
– Superior – optic chiasm

6. • Tributaries:
– Superior and inferior opthalmic veins
– Sphenoparietal sinus
– Inferior cerebral veins
– Superficial middle cerebral veins
– Central vein of retina
• Drainage:
– Superior petrosal sinus---> transverse sinus
– Inferior petrosal sinus --->internal jugular vein

7. • Tributaries:
– Superior and inferior opthalmic veins
– Sphenoparietal sinus
– Inferior cerebral veins
– Superficial middle cerebral veins
– Central vein of retina
• Drainage:
– Superior petrosal sinus---> transverse sinus
– Inferior petrosal sinus --->internal jugular vein

8. • Communication:
– Intercavernous sinuses – communication between the two
– Pterygoid plexus – via emissary veins passing through
foramen ovale, emissary sphenoidal foramen and foramen
lacerum.
– Pharyngeal plexus – via a vein passing through carotid canal.
– Facial vein – via superior opthalmic vein.

9. Contents of cavernous sinus
• - Internal Carotid artery with sympathetic plexus
• - CN 3
• - CN 4
• - CN 5 (1st and 2nd divisions)
• - CN 6

10. Cavernous sinus thrombosis

11. • Includes cases of phlebitis, thrombo-phlebitis
and aseptic thrombosis
• Septic type (most common) - coagulase
positive staphylococcus
• Aseptic types may follow trauma, local stasis
or a failing circulation.

12. Causes
Septic CST
• Infectious
Aseptic CST
• Trauma
• Post surgery
Rhinoplasty
Base of skull
Tooth extraction
• Hematologic
• Malignancy
Nasopharyngeal Ca.
• Dehydration

13. • More commonly seen with sphenoid and
ethmoid and to a lesser degree with frontal
sinusitis
• Staphylococcus aureus -70% of all infections.
Streptococcus pneumoniae, gram-negative
bacilli, and anaerobes can also be seen.
• Fungi are a less common pathogen and may
include Aspergillus and Rhizopus species(more
common in diabetics)

14. Spread of infection
• No valves in dural sinuses, cerebral and
emissary veins
• Infection of upper lip, vestibule of nose and
eyelids-> spread by way of angular,
supraorbital, supratrochlear veins to
ophthalmic veins=commonest route
• Intranasal operation of septum, turbinates,
ethmoid/sphenoid sinus infection->through
ethmoidal veins

16. • Operation of tonsil, peritonsillar abcess,
maxillary osteomyelitis/surgery, dental
extraction->spread by pterygoid plexus or
direct extension in internal jugular vein
• Involvement of middle ear/mastoid ->
retrograde spread through petrosal sinus to
cavernous sinus

18. Sources:
• Nose – Paranasal 40%
• Orbit- Face 35%
• Mouth – Teeth 13%
• Ear 9%
• Other – tonsil, soft palate, pharynx, posterior
portions of the superior and inferior alveolar
arches 3%

20. Clinical features
1. Sepsis
2. Venous obstruction
3. Involvement of cranial nerves

21. Sepsis
• Pyrexia
• Rapid, weak, thready pulse
• Chills and sweats
• Delirium - meningitis supervenes terminally
• Septic emboli to various other parts of body.

22. Venous obstruction
• Proptosis (first oedema & chemosis)
• Oedema of eyelids and bridge of nose
• Dilatation and tortuosity of retinal veins
• Retinal hemorrhages
• Involvement of the contralateral eye – (48
hours)
• When pterygoid plexus is occluded along with
sinus, - oedema of the pharynx or tonsil

23. Involvement of cranial nerves
• First CN involved is VI
• Ptosis - paralysis of oculomotor nerve
• Dilatation of pupil- third nerve and stimulation of
sympathetic plexus
• Decreased abduction (paralysis of abducens
nerve)
• Complete opthalmoplegia
• Loss of vision
• Retro-orbital pain and supra-orbital headache->V

25. Diagnosis
• Strong clinical suspicion
1)Orbital venography
• Not recommended
• Difficult to puncture facial veins in odema
• May help in dissemination of infection

26. 2) Contrast enhanced CT
• Slice thickness 3mm or less
• Shows enlargement and expansion of cavernous
sinus cavity with flattening or convexity of lateral
wall
• Multiple or single filling defect with enhancing
CS.
• Exopthalmos, soft tissue edema
• Dilation of superior ophthalmic vein

28. 3) MRI:
• – A sensitive, noninvasive
• Can be combined with venography to
demonstrate lack of blood flow in the
cavernous sinus
• Show associated meningitis, involvement of
pituitary gland

30. 4) CSF examination
• Elevated protein
• Normal sugar
• Mild pleocytosis
5) Complete blood count
• Elevated TLC
• Leucocytosis
6) Blood culture
7) Local tissue culture

31. Complications
• Intracranial extension of infection->
meningitis, encephalitis, brain abcess,
pituitary infection,epidural, subdural
empyema
• Cortical vein thrombosis->hemorrhagic
infarction
• Extension to other sinuses

32. Differential Diagnoses
• Orbital cellulitis–differentiated from CST by B/L
involvement, papillodema, dilated pupil, decreased
periocular sensation, abnormal spinal fluid in latter
• Preseptal cellulitis- no proptosis
• Orbital apex syndrome- more visual loss,
opthalmoplegia, less proptosis, periorbital odema
• Sinusitis
• Orbital malignancy
• Facial Cellulitis
• Glaucoma-angle closure

33. Treatment

34. Antibiotics
• Immediate empiric antibiotic coverage must
include gram-positive, gram-negative and
anaerobic bacteria.
• Later treatment can be narrowed, adjusted to
cultures and sensitivities
• Third generation cephalosporin + vancomycin
with metronidazole
• Duration- 3-4 weeks

35. Antifungals
• Used in setting of fungal sinusitis
• More common in diabetics
• Aspergillus more common
• Parentral amphotericin B for 3 weeks followed
by posaconazole(400mg BD) prophylaxis
• Dose-0.5-1.5mg/kg/day(deoxycholate), 5-
10mg/kg/day(liposomal)

36. Anticoagulation
• Intravenous heparin (maintaining the partial
thromboplastin time or thrombin clot time at
1.5 to 2 times that of the control)->24,000-
30,000 U/day.
• Warfarin sodium (maintaining the
prothrombin time at 1.3±1.5 times the
control) -continued for 4 to 6 weeks to allow
adequate collateral channels to develop

37. • Mortality was lower among patients who
received heparin treatment, 14% vs. 36%
• Early administration of heparin may serve to
prevent spread of thrombosis to the other
cavernous sinus as well as to the inferior and
superior petrosal sinuses.

38. Steroids
• Not influence mortality
• May prevent residual cranial nerve
dysfunction caused by inflammation.
• Dexamethasone used most commonly

39. Surgical treatment
• Surgical drainage of affected sinuses
• Endoscopic sinus surgery
• Surgical debridement in fungal sinusitis
• Surgical drainage of any collection

40. Prognosis
• 100% mortality prior to antibiotics
• 30% mortality despite aggressive treatment
• 44% of survivors remain with chronic sequelae,
• Roughly one sixth of patients are left with some
degree of visual impairment
• One half have cranial nerve deficits
• Hypopituitarism- rare, can occur before or after 1
year.

41. References
• Septic cavernous sinus thrombosis-Neurology
and Neurosciences;2014;4:117-118
• Treatment of Cavernous Sinus Thrombosis;
IMAJ 2002;4:468±469
• Septic thrombosis of cavernous sinus-Arch
Intern Med;2001;161:2671-2676

42. Thank You