Orbit Flashcards
(42 cards)
1
Q
Orbit
A
- Protect, support and maximise function of the eye
2
Q
Orbit Anatomy
A
- Orbit is surrounded by orbital bones
- Orbital fat fills space between nerves and muscles - acts as a cushion
3
Q
Clinical Features
A
- Proptosis (bulging of the eye)
- Reduction in VA
- Pain
- Diplopia
4
Q
Clinical Evaluation
A
- Complete ophthalmic examination
- Careful H&S, including time course of the disease, past trauma, ocular surgery and systemic illnesses
- Assessment of VA, VF, anterior and posterior segment evaluation, and external periorbital inspection
5
Q
Investiagations
A
- Imaging (CT/MRI/US)
- Systemic investigations depending on clinical suspicion (e.g. blood tests such as thyroid function tests)
- CT - good for bone abnormalities
- MRI - good for soft tissues
6
Q
Diffuse Idiopathic Orbital Inflammation Symptoms
A
- typically unilateral in adults but can be bilateral in children
- abrupt pain
- diplopia
7
Q
Diffuse Idiopathic Orbital Inflammation - Signs
A
- Ocular and periocular redness
- Conjunctival injection
- Chemosis
- Lid oedema
- Proptosis
- Exophthalmos
- Motility restriction
- No systemic manifestations (systemic symptoms common in children)
- Palpable mass detected in 50% of cases
8
Q
Diffuse Idiopathic Orbital Inflammation - Management
A
- Observation for mild disease, in anticipation of remission
- Systemic corticosteroids typically result in a dramatic improvement
Prognosis generally excellent
9
Q
Myositis
A
- Acute to subacute idiopathic inflammation of the EOM muscles
- Usually connected/related to other systemic diseases such as rheumatoid arthritis
10
Q
Myositis Symptoms
A
- Onset - usually early adulthood
- Pain (worsened by eye movement)
- Motility restriction
- Diplopia
11
Q
Myositis Signs
A
- More subtle than IOI (above)
- Lid oedema
- Ptosis
- Chemosis
- Exophthalmos
- Displacement of the globe
- Vascular injection over affected muscle
12
Q
Myositis Management
A
- Aim - relieve discomfort and dysfunction
- Systemic corticosteroids
- Recurrence seen in 50%
13
Q
Acute Dacryoadenitis
A
- May be idiopathic or due to viral infection
- Can be bilateral
- Presentation in acute disease is with rapid onset of discomfort in region of lacrimal gland
- May have increase/decrease in LG secretion, tender LG
- Possible chemosis
- Discharge may be reported
- Swelling of lateral aspect of eyelid (s-shaped ptosis)
- Occasionally proptosis
- Treatment varies but not required in many cases
14
Q
Orbital Cellulitis
A
- Bacterial infection of tissue POSTERIOR to orbital septum
- May develop from preseptal cellulitis
- Main causes:
- Sinusitis
- Lid or face infection
- Foreign body
- hordeolum
- dental abscess
- Haematogenous
- Can spread fast, especially in children
15
Q
Orbital Cellulitis Symptoms
A
- Sudden onset (more rapid than preseptal), unilateral
- Pain
- Chemosis
- Abaxial displacement (if abscess forms)
- Possibly raised IOP
- Systemic symptoms such as a fever or feeling very unwell
- Rapid loss of vision may occur from:
- Optic nerve compression
- Reduced VA
- Impaired colour vision
- RAPD
- Make this almost certain
- Optic neuritis
- Vasculitis
- Optic nerve compression
16
Q
Orbital Cellulitis Signs
A
- Lid oedema and erythema (redness)
- Dilated pupil
- Motility - restricted range of movements, pain and diplopia reported
- Proptosis (if diffuse disease occurs)
- Marked ophthalmoplegia (weakness of EOM muscles?)
- RAPD in the affected eye
- Impaired colour vision
- Papilledema
- Perivasculitis
17
Q
Orbital Cellulitis Management
A
- Children - systemic antibiotics, sinus drainage only needed in 50% of cases
- Adults - sinus and abscess drainage needed in 90% of cases
- urgent/same day referral
18
Q
Preseptal Cellulitis
A
- Bacterial infection of tissue ANTERIOR to the orbital septum
- Bacteria may spread from nearby site:
- Ocular (e.g. hordeolum, conjunctivitis)
- Trauma (e.g. tree branch, insect bite)
- May be spread of more remote infection:
- Sinusitis
- Middle ear infection
- Less common and less severe than orbital
19
Q
Preseptal Cellulitis Symptoms
A
- Most common in children (<10 yrs)
- Typically unilateral
- Swelling and redness of eyelids (tender eyelids also)
- Pyrexia (fever, raised temp)
- Malaise (general unwell feeling)
- Irritability in children
20
Q
Preseptal Cellulitis Signs
A
- Erythema (redness) of skin surrounding eye
- Warm skin surrounding eye
- Tender ocular region
- Eyelid oedema
- Increased weight of upper lid may cause ptosis
- Narrowed palpebral aperture
- CT scan - useful to exclude orbital cellulitis
21
Q
Preseptal Cellulitis Management
A
- Risk of mis diagnosing orbital cellulitis as preseptal
- Preseptal can progress to orbital in children
- Emergency referral to ophthalmologist (telephone call)
- IP optometrists can prescribe oral antibacterial drugs for adults if diagnosis is not in doubt
22
Q
Orbital vs Preseptal
A
- Orbital more severe than preseptal
- Orbital more sudden onset than preseptal
- No proptosis and chemosis in preseptal
- VA, pupil reaction, ocular motility unimpaired in preseptal
23
Q
Rhino-orbital Mucormycosis
A
- Aggressive rare fungal infection
- Acquired by inhalation of spores giving rise to an upper respiratory infection
- Spreads to sinuses, orbit and brain
24
Q
Rhino-orbital Mucormycosis Symptoms
A
- Gradual onset facial and periorbital swelling
- Diplopia
- Vision loss
25
Rhino-orbital Mucormycosis Signs
- Similar to orbital cellulitis
- But less acute and slower progression
- Complications include:
- Retinal vascular occlusion
- Multiple CN palsies
- Cerebrovascular occlusion
26
Rhino-orbital Mucormycosis Management
- Correction of underlying metabolic defect if possible
- Intravenous antifungal treatment
27
Lacrimal Gland Tumours
- Infiltrative processes (such as inflammatory disease and lymphoma)
- Structural disorders (such as cysts)
- Epithelial tumours represent 20-25% of all LG lesions
- Almost all LG lesions result in a mass effect, with swelling of the lateral eyelid and often a downward and medial displacement of the globe
- Inflammation causes:
- Pain
- Chemosis
- Oedema
28
Lacrimal Gland Tumours - Pleomorphic Adenoma & Adenoid Cystoid Carcinoma
- Pleomorphic adenoma (benign mixed cell tumour) - do not biopsy, potential to become malignant, 25% of lacrimal mass lesions
- Adenoid cystoid carcinoma - 23% commonly in the fourth decade of life
29
Lacrimal Gland Tumours signs/symptoms
- Exophthalmos
- Downward globe displacement
- Ptosis
- Diplopia
- Pain as a result of perineural invasion
- Treatment involves surgical incision
- High mortality rate
30
Paediatric Orbital Tumours
- Dermoid cysts (benign)
- Capillary haemangioma (most common)
- Rhabdomyosarcoma (aggressive, tend to be fatal)
31
Adult Orbital Tumours
- Lymphoid tumours
- Cavernous haemangioma
- Meningiomas
32
Orbital Tumours Investigation and Treatment
- Imaging
- Incisional or excisional biopsy
- Radiotherapy
- Chemotherapy
- Complication of treatments
33
Optic Nerve Glioma
- Typically affects children
- Prognosis variable
34
Optic Nerve Glioma - Symptoms
- Slowly progressive visual loss
- Followed by proptosis (sequence may be reversed)
35
Optic Nerve Glioma - Signs
- Proptosis
- ONH initially swollen, becomes atrophic (loss of nerve fibres?)
- CRVO often seen
- Intracranial spread to chiasm and hypothalamus may develop
36
Optic Nerve Glioma Management
- Resection means all vision in operated eye will be lost, as tumour is intrinsic to ON
- Observation in px's where tumour is confined to orbit, especially if good vision and no significant cosmetic impairment
- Surgical excision with preservation of the globe for those with large/growing tumours
- Radiotherapy may be combined with chemotherapy for tumours that preclude surgical excision
37
Optic Nerve Sheath Meningioma
- Benign tumour
- Tumour may invade ON, or encircle it
- Less common than optic nerve gliomas
- Typically affect middle aged women
- Prognosis good in adults, although tumour may be more aggressive in children
38
Optic Nerve Meningioma Symptoms
- Gradual visual impairment in one eye
- Transient obscuration of vision may occur
39
Optic Nerve Meningioma Signs
- Visual loss
- Optic atrophy
- Opticociliary shunt vessels
- Simultaneous occurrence of all 3 (above) uncommon
- Motility defects (particularly in upgaze)
- Proptosis
40
Optic Nerve Meningioma Management
- May not be required for middle aged px with slow growing tumour
- Excision for aggressive tumour, especially if eye is blind or risk of intracranial extension
41
Orbital Trauma Signs
- Orbital floor fractures most common
- Oedema and ecchymosis of the eyelids and periorbital region
- Diplopia, enophthalmos (sunken eye), or hypoesthesia (lack of sensation) of the cheek and gum
42
Orbital Trauma - Investigation & Treatment
- CT scan
- Examination of globe
- Charting of ocular motility
- Surgical repair (orbital floor)
