Lids 4 - Orbital eye diseases Flashcards
Orbit anatomy features:-
• Height of orbital - 40 mm
• Width of orbital - 35 mm
• Depth of orbit - 40-50 mm
• Interorbital distance - 25 mm
• Volume of orbit - 30 cm3
• Anatomical space bounded by the orbital bones
• Anteriorly the orbit is limited by the orbital septum, which represents the most anterior layer of the orbital septal system and separates the orbit from the eyelid
• Orbital fat fills the space between nerves and muscles and acts as a cushion
Orbit patholgies fall into 3 categories:-
•Inflammation
- thyroid disease
- cellulitis
• Compression
- Tumours
- Inflammation
• Both
Symptoms:
•Proptosis
• ? Va
• Pain
• Diplopia
Clinical evaluation of orbit:-
• Complete ophthalmic examination
• Careful medical and ophthalmic history, including time course of the disease, past trauma, ocular surgery, and systemic illnesses
• Assessment of visual acuity and visual fields, anterior and posterior segment evaluation, and external and periorbital inspection
Investigations techniques:-
• Imaging (CT-MRI-US)
• Systemic investigations depending on clinical suspicion
Modern imaging techniques and their uses:-
• CT-Good for bony abnormalities
• MRI-Good for soft tissues
Signs/symptoms, diagnosis and treatment of orbital inflammation:-
• Painful proptosis
• Red eye, chemosis
• Myositis -> limitation of movement
• Occurs anywhere in orbit, specially around lacrimal gland
• Diagnosis
- Orbital CT scan- U/S
• Biopsy
• Treatment
- Steroids
What is Thyroid Orbitopathy, and its risk factors?
• Graves disease
• Immunological disorder that affects the orbital muscles and fat
- Multiple muscles are involved simultaneously, most commonly the inferior and medial rectus
• It is always a bilateral process but is often asymmetrical.
Risk factors:
• Middle-aged adults (30-50 years) are affected most frequently
• The disease is seen in women more commonly than in men, in a ratio of 3-4:1.
Thyroid Orbitopathy - Symptoms and signs
Signs:
• Exophthalmos
• Conjunctival injection
• Lid retraction
• Corneal exposure
• Rarely optic nerve compression
Symptoms:
• Dry eyes
• Diplopia
Treatment depending on severity and Prognosis of Thyroid eye disease:-
Mild cases
• Topical lubrication and steroids
Medium cases
• Oral immuno-suppresion
• Low dose radiotherapy
Severe (Inflammation)
• Soft tissue and bony decompression
• Upper lid lowering- chemosis
• Lower lid elevation- chemosis
• Squint surgery - muscles
• Disease stabilization can take up to 12 years
What are the 3 types of orbital Inflammatory disorders?
• Diffuse Idiopathic Orbital Inflammation (Pseudotumor)
• Myositis
• Orbital Cellulitis
Orbital Cellulitis causes and symptoms:-
Major causes:-
• Sinusitis
• Lid or face infection
• FB
• Blood infections
Symptoms:-
• Pain
• Lid oedema
•Chemosis
• Axial proptosis if diffuse disease occurs or abaxial displacement if an abscess forms
• Decreased ocular motility
• Intraocular pressure may be elevated
• Optic nerve compression - Affects VA
May go on to cause:
• Optic neuritis
• Vasculitis
• Cavernous sinus thrombosis
Orbital Cellulitis Warning Signs/Symptoms and drainage?
•The warning signs of orbital cellulitis are a dilated pupil, marked ophthalmoplegia, loss of vision, afferent pupillary defect, papilledema, perivasculitis, and violaceous lids
Systemic symptoms
•In children, treatment is with systemic antibiotics; sinus drainage is needed in only 50% of cases. in adults, the drainage of sinuses and abscesses may be needed in 90% of cases
What is Diffuse idiopathic orbital inflammation (Pseudotumour), symptoms, its types and prognosis?
• A palpable mass is detected in 50% of cases.
Symptoms include:
• abrupt pain, conjunctival injection, chemosis, lid oedema, exophthalmos, and motility restriction
Type:
• No systemic manifestations
• Sclerosing versus non-sclerosing
Prognosis:
• Systemic corticosteroids typically result in a dramatic improvement
• Prognosis generally is excellent
What is Myositis, its symptoms and treatment?
• An acute to subacute idiopathic inflammation of the extraocular muscles
• Symptoms include pain, motility restriction, exophthalmos, and displacement of the globe
• Systemic corticosteroids generally result in prompt resolution
What are 3 causes Lacrimal gland disorders and their signs/symptoms?
• Infiltrative processes (such as inflammatory diseases and lymphoma)
• Structural disorders (such as cysts)
• Epithelial tumours represent 20-25% of all lacrimal gland lesions
Signs/symptoms include:
• lacrimal gland lesions result in a mass effect, swelling of the lateral eyelid and often with a downward and medial displacement of the globe
• Inflammation causes pain, chemosis and oedema
