Ординатура / Офтальмология / Английские материалы / Moorfields Manual of Ophthalmology_Jackson_2007
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Optometry and General
Practice Guidelines
Children with any eyelid abnormality should be referred early to detect and manage amblyopia. Adult eyelid malpositions (entropion/ectropion) may be managed routinely unless there is ocular surface irritation either from a stagnant tear film or aberrant lashes. Half-inch micropore tape applied along the lower lid and brought up onto the temple will tighten the lid and provide a temporary correction of lid laxity.
The majority of cases of facial palsy are idiopathic (Bell’s palsy) and will not require tarsorrhaphy, but should be referred urgently to determine other risk factors for corneal exposure (e.g. reduced corneal sensation or Bell’s phenomenon). Similarly, corneal exposure from any cause of lid malposition (e.g. entropion)
should be dealt with urgently. Look for staining with 2% fluorescein dye in the exposed corneal areas. Refer suspected tumours urgently.
Any patient with presumed eyelid infection with breakdown or frank necrosis of the overlying skin should be given intravenous antibiotic (e.g. penicillin V or co-amoxyclav) and referred immediately. Necrotizing fasciitis is rare but has a high mortality.
Injuries to the eyelids require urgent attention, in particular upper eyelid trauma where there may be a risk of corneal exposure, and a risk of undetected globe, orbital, or even intracranial injury. The risk of corneal exposure is higher where there is eyelid margin injury. Patients with canalicular trauma should also be referred urgently, because a successful anatomical union becomes more difficult after 24–36 hours.
The following guidelines for hospital referral urgency are not prescriptive, as clinical situations vary.
Immediate
■ Periorbital infection with suspected skin necrosis |
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(necrotizing fasciitis) |
p. 30 |
Same day |
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■ Eyelid lacerations |
p. 50 |
■ Canalicular laceration, etc. |
p. 50 |
■ Acute adult ptosis with associated motility disorder |
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and nonreactive pupil indicating a third nerve palsy |
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(refer urgently to neurosurgeon or neurologist) |
p. 612 |
OCULOPLASTICS 1 Chapter
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Optometry and general practice guidelines
Urgent (within 2 weeks)
■ Paediatric ptosis |
p. 26 |
■ Suspected eyelid neoplasia, and atypical or |
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recurrent eyelid lesions |
p. 39 |
■ Entropion with corneal epitheliopathy, evidence of |
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lash–cornea touch, or corneal scarring |
p. 16 |
■ Ectropion or upper lid retraction with evidence of |
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corneal exposure |
p. 9 |
■ Bell’s palsy |
p. 22 |
■ Trichiasis with corneal fluorescein staining |
p. 19 |
Soon (within 1 month) |
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■ Molluscum contageousum |
p. 32 |
■ Pyogenic granuloma |
p. 35 |
■ Recent onset or unilateral facial dystonia (muscle |
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spasm) |
p. 45 |
■ Trichiasis without corneal fluorescein staining |
p. 19 |
Routine |
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■ Adult ptosis |
p. 26 |
■ Eyelid malposition without corneal exposure or |
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irritation |
p. 9, p. 16 |
■ Floppy eyelid syndrome |
p. 15 |
■ Chalazion |
p. 28 |
■ Squamous papilloma |
p. 31 |
■ Keratoacanthoma |
p. 31 |
■ Actinic keratosis |
p. 39 |
■ Pilar cyst |
p. 32 |
■ Cyst of Moll |
p. 33 |
■ Eyelid naevus |
p. 36 |
■ Xanthelasma |
p. 36 |
■ Longstanding bilateral facial dystonia (muscle |
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spasm) |
p. 45 |
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Chapter 2
LACRIMAL
The Watery Eye
Anatomy and Physiology The tear film provides corneal lubrication, nourishment and protection, has anti-infective properties, aids removal of bacteria, cells, and debris, and optimizes the optical interface between air and cornea. It is triphasic, comprising a mucoid layer (from goblet cells), aqueous layer (primarily lacrimal glands but also accessory glands of Krause and Wolfring), and lipid layer (meibomian glands).
Symptomatic watering results from reduced tear removal (by evaporation and drainage) and/or overproduction. Obstructive epiphora refers to reduced tear drainage. Tear distribution is also important, as is eyelid movement (‘lacrimal pump’) and position. Patient tolerance of watering varies widely.
Consider the lacrimal drainage system as three compartments:
1.Tear lake.
2.Lacrimal sac.
3.Nasal cavity.
Relatively high-resistance conduits connect these compartments; the canaliculi (connecting compartments 1 and 2), and nasolacrimal duct (2 and 3) (Fig. 2.1):
■Canalicular obstruction produces ‘flow’ symptoms: ‘Eyes well up with water’, blur on downgaze, e.g. reading. ‘Volume’ symptoms are minimal or absent.
■Nasolacrimal duct obstrucition (NLDO) produces ‘volume’ symptoms due to backwash from the lacrimal sac. These include: recurrent conjunctivitis; morning stickiness; mucus debris in the tear film; dacryocystitis; lacrimal sac mucocele or abscess.
History Assess severity – symptoms indoors are more |
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significant than those outdoors in cold, windy weather. Ask about |
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onset, time relationships, duration, and site of tear spillover. |
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Medial spillage suggests impaired drainage; lateral spillage may |
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relate to lower lid laxity, or upper lid dermatochalasis contacting |
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the tear film with chronic skin wetting by capillary action. Reflex |
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eye |
Vertical |
Horizontal |
Common |
canaliculus (2mm) |
canaliculus (8–10mm) |
canaliculus (0–5mm) |
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watery |
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Valve of |
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50° |
Rosenmuller |
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Lacrimal |
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The |
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sac (12–15mm) |
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Middle turbinate |
Nasolacrimal |
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duct (15–18mm) |
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Valve of Hasner |
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Inferior turbinate |
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Fig. 2.1: Lacrimal drainage anatomy. The angle between the horizontal and common canaliculi in the axial plane is approx. 135 degrees. Therefore, one must pull the lid laterally when probing the common canaliculus (during intubation, e.g. at DCR) to straighten out this angle
to 180 degrees, thus preventing a ‘false passage’ and canalicular perforation.
NB: When performing diagnostic outpatient syringing, advance the cannula not more than 5–6 mm into the horizontal canaliculus to avoid common canalicular injury.
watering from tear-film deficiency is often worse in dry, warm conditions, bright light, or when blinking is reduced, e.g. concentrating on reading, computer use, and Parkinson’s disease. Simultaneous runny nose suggests overproduction. Bloody tears suggests a sac tumour (rare), canaliculitis, or trauma to the canaliculi/sac (including iatrogenic injury). Ask about surface irritation or itch (atopy), a history of facial/nasal trauma, and previous nasal or lacrimal surgery. ‘Crocodile tears’ are associated with facial palsy and involve neurogenic reflex watering, often sudden, from the thought of food, eating, or chewing. Lacrimal sac swelling may be secondary to a dacryocele (a congenital cyst), mucocele (see below), pyocele, dacryocystitis (painful), tumour (usually painless ± bloody tears), or occasionally air (± pain).
Examination Examine for causes of overproduction or 56 impaired drainage.
■Overproduction : Look for:
1.Lid or lash malposition – trichiasis, distichiasis, entropion.
2.Lid margin disease (p. 113).
3.Tear film deficiency – perform Schirmer’s test (p. 147) and tear film break-up time (p. 157).
4.Corneal or subtarsal foreign body.
5.Conjunctivitis – look for allergic papillae, follicles.
6.Corneal disease, especially superficial punctate keratopathy from tear film anomalies or exposure keratopathy, and early dendritic keratitis.
7.Uveitis, scleritis.
■Impaired drainage : Look for:
1. Eyelid laxity or malposition of the lower lid or punctum particularly ectropion.
2. Punctal or canalicular stenosis-cicatrizing conjunctivopathy, systemic chemotherapy, especially 5 FU and trauma (including iatrogenic).
3.Canaliculitis (see p. 67).
4.Fistula – congenital, or acquired (following dacryocystitis).
5.Lacrimal pump failure – especially facial palsy.
6.Lacrimal sac mucocele – this is a chronic collection of mucopurulent material due to low grade colonization/ infection of stagnant tears. Pressing on the sac produces mucus or pus reflux (Fig. 2.2). A dacryocystorhinostomy (DCR) is often required for associated epiphora.
7.Lacrimal sac mass – consider tumour or tense mucocoele. In general, a mass below medial canthal tendon (MCT) originates from the sac; lesions above the MCT indicate non-sac origin.
8.Dacryocystitis – active or resolved (p. 68).
9.Nasal obstruction, e.g. mass, inflammation, scarring. If it is possible to gently pass a cotton bud alongside the lateral wall of the nose, this suggests a reasonable nasal airway is present; if not, consider endoscopy.
10. Altered facial/lid relationship – this may include prominent eyes, lower lid sag and hypoplastic midface.
11. Prior surgery or trauma – look for scars.
LACRIMAL 2 Chapter
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The watery eye
Fig. 2.2: Mucocele with mucous reflux.
Clinical tests
■Fluorescein disappearance test (FDT) : Instil a tiny drop of fluorescein 2% in both eyes at the start of history taking. After approximately 5 minutes, look for asymmetry in the tear film height.
High + diluted = overproduction.
High + undiluted = impaired drainage.
■Syringing : Perform a diagnostic lacrimal syringing in all patients with epiphora, except those with acute dacryocystitis
in whom the procedure is usually painful. Consider patient comfort and use a reclining chair with head support. Be very gentle to avoid canalicular trauma. In experienced hands the procedure is painless, even without topical anaesthesia. If necessary, dilate the punctum (after topical anaesthetic), but avoid tearing the fibrous annulus and avoid sharp dilators. Keep the lower lid under firm lateral tension to eliminate the angle between the horizontal and common canaliculus and hence prevent canalicular perforation (‘false passage’). Gently inject saline using a 2.5 mL syringe with a lacrimal cannula, inserted no more than 5 mm into the horizontal canaliculus. It is seldom necessary to check for ‘hard’ or ‘soft stops’ by pushing the cannula up against the nasal bones. Lower canalicular reflux suggests obstruction proximal to common canaliculus. Upper canalicular reflux with fluorescein or mucus reflux which suggests a mucocele nasolacrimal duct obstruction (NLDO). Early reflux via the upper canaliculus
58 without fluorescein suggests common canalicular obstruction.
■Jones I dye test : Assesses physiological drainage. Instil fluorescein 2%, then insert a cotton bud under the inferior turbinate – if there is dye on the cotton bud, the test is positive. Nasal endoscopic visualization is more accurate. A negative result indicates nonpatency, partial patency, or functional NLDO. The test is most useful following DCR; otherwise, it is less reliable.
■Jones II dye test (nonphysiological): As per Jones I but after syringing. Jones II dye test is not needed if Jones I is positive.
Investigations
■Dacryocystogram (DCG): Indications include a failed DCR or trauma without mucocele (surgery for post-traumatic or recurrent mucocele is relatively straightforward in experienced hands so DCG is not needed), suspected functional NLDO (shows delayed clearance from sac on late erect films), bloody epiphora, and unusual craniofacial syndromes.
■CT: Perform if suspected sinonasal disease, lacrimal tumours, and in some cases following trauma, especially if metallic implants are suspected.
■Scintigraphy : Can distinguish between delayed drainage between compartments 1 and 2 (impaired ‘pick up’ of tears), and 2 and 3 (anatomic/functional obstruction).
■Nasoendoscopy : Occasionally required.
Management
■Overproduction : Treat the underlying cause, e.g. lid hygiene, lash removal, topical lubricant, steroid, or antibiotic.
■Impaired drainage :
Lid malposition – surgical correction. Punctal stenosis – punctoplasty (Box 2.1).
■Canalicular stenosis :
Proximal : DCR + retrograde canaliculostomy (canaliculi are intubated from within the opened lacrimal sac and a ‘cutdown’ performed distal to the site of obstruction).
Distal : canalicular-DCR (C-DCR; canaliculi are anastomozed to sac flaps after excision of intervening scar tissue, or scar is
excised from within the sac until the probes are seen – stents passed directly into the sac) ± lacrimal canalicular bypass, e.g. Lester Jones tube (LJT).
LACRIMAL 2 Chapter
■ Canaliculitis : See page 67. |
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The watery eye
Box 2.1: Punctoplasty (‘3-snip’ or posterior ampullectomy)
1.Dilate lower punctum with a punctum dilator, e.g. Nettleship.
2.Make two parallel cuts (medial and lateral) in the posterior wall of the vertical canaliculus (ampulla) and join at the bottom with fine, straight scissors (e.g. Vannas).
3.Incise 2–3 mm along horizontal canaliculus from the conjunctival surface.
4.Excise ‘triangle’ of ampulla and conjunctiva between these two incisions.
5.Gently cauterize conjunctiva at wound edges.
6.Prescribe G. chloramphenicol q.d.s. and mild topical steroid q.d.s. for 2 weeks.
7.Review in 2–3 weeks.
■Acute dacryocystitis (lacrimal sac abscess): See page 68.
■Mucocele or functional NLDO : DCR (see below).
■Lacrimal sac tumour: Biopsy sac; if discovered intraoperatively, abandon DCR and excise the sac.
■Lacrimal pump failure (‘atonic canaliculi’): Difficult to treat. Tighten/shorten lid ± punctoplasty ± DCR ± lacrimal bypass (e.g. LJT).
■Nasal congestion : Prescribe a nasal decongestant, e.g. xylometazoline hydrochloride nasal spray 0.1%, 1 spray per nostril, 2–3 times daily for 2–4 weeks. Beware interactions with monoamine oxidase inhibitors, etc., and avoid use over 5–7 consecutive days to avoid rebound rhinorrhoea. Also prescribe steroid, e.g. beclamethasone dipropionate/Beconase nasal spray 50 mcg/metered spray, 2 sprays per nostril b.d. for 2–3 weeks. Consider an ENT opinion.
■Congenital NLDO see page 65.
Dacryocystorhinostomy
Background Aims to create a mucosal-lined anastomosis between the sac and nose using an external (open) or endoscopic approach. External DCR remains the ‘gold standard’ with larger
60 rhinostomy, and first-intention flap healing. An external approach
is absolutely indicated if sac tumour is suspected (if confirmed, biopsy the sac but do not complete DCR), and for canalicular disease. For technique see Box 2.2.
Consent
■Benefit : External DCR success rate is 90–95%; endoscopic surgical, 80%; endoscopic laser, 70–80%. Success varies
Box 2.2: Dacryocystorhinostomy (DCR)
1.Select general anaesthetic (GA) or local anaesthetic (LA) with sedation (lignocaine 2% and bupivicaine 0.5% with 1 : 200 000 epinephrine in side of nose, medial peribulbar, infraorbital nerve block, plus cocaine 10% intranasally).
2.Haemostasis is assisted by head-up position, BP control, intranasal 0.1% epinephrine moistened cotton buds or cocaine 10% nasal pack.
3.Stat cefuroxime 750 mg i.v. reduces the postoperative infection rate.
4.Make a straight incision 1 cm anterior to the medial canthus, approx. 1.5 cm long, raise skin flap and expose MCT using blunt dissection (Rollet’s rougine).
5.Dissect MCT and periosteum from anterior lacrimal crest, release sac, especially superiorly, and mobilize laterally.
6.Start rhinostomy by opening suture between nasal and lacrimal bones with Traquair periosteal elevator. Use bone punch, e.g. Kerrison’s rongeurs, to extend as far superiorly and anteriorly as possible, inferiorly (level with inferior orbital rim) and posteriorly (to the posterior lacrimal crest). Rhinostomy should measure about 2–3 cm in diameter (Fig. 2.3). Protect nasal mucosa from inadvertent perforation.
7.Perform anterior ethmoidectomy with curved haemostat or bone nibbler.
8.Fully open sac from fundus to duct and fashion sac and nasal
mucosal flaps, using all available rhinostomy space. Incise nasal mucosa >3 mm anterior to root of middle turbinate – anterior nasal mucosal flap should be larger than posterior (Fig. 2.4). Suture flaps with 6/0 Vicryl. ‘Suspend’ anterior flaps to overlying orbicularis.
9.Insert O’Donoghue tubing or similar stent. Tie tubing in the nose and place a marker stitch, e.g. 5/0 silk to aid later stent removal.
10.Carefully close skin with 6/0 nonabsorbable suture. Keep closure
LACRIMAL 2 Chapter
flat and avoid ‘bow-stringing’. |
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The watery eye |
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Lacrimal |
Maxilla |
Bony ostium |
Nasal |
bone |
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size (maximal) |
bone |
Fig. 2.3: Dacryocystorhinostomy: rhinostomy.
Nasal mucosal flaps
Bony ostium
Opened lacrimal sac
Nasolacrimal duct
Fig. 2.4: Dacryocystorhinostomy: mucosal flaps.
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