Epidural infusions are not without risk. It is essential that close nursing supervision is maintained (i.e. vital signs and level of the epidural block). In many hospitals there is a \200\230pediatric pain team \200\231 who supervise the epidural. If this is not available , close liaison should be maintained with the anesthetist responsible. If the level of anes thesia seems to be rising to the upper thoracic dermatomes the infusion should be stopped p ending advice. If the analgesia is inadequate advice should be sought before either removin g the epidural catheter or starting opiates. Continuous IV infusion of morphine Infusion of morphine or other opiates is another very ef fective method of post-operative analgesia. For older children, this may be in the form of a patient-controlled analgesia pump with a button the child can press to obtain an incremen t of analgesic. \200 Most hospitals will have guidelines on the use of analgesics for children that should be fo llowed. \200\230Pain ladders \200\231 providing options for analgesics of increasing poten cy are becoming common. It is not acceptable to leave a child in pain and it is simply untr ue that administering strong analgesics will mask clinical signs. Peritonitis can be detect ed reliably in a child who has received morphine. 23_McClure_23.indd 890 11/14/2012 3:30:27 PM POST-OPERATIVE CARE: DRAINS AND WOUNDS 891 Post-operative care: drains and wounds Chest drain removal An adult can be asked to suspend respiration in full inspiration before removal of a chest drain. Children will not co-oper ate with this. \200 The best strategy is to remove the drain quickly. Then cover the site with an air-tight tra nsparent dressing (e.g. Tegaderm \204 ). The dressing should remain undisturbed for 48hr af ter which time the wound can be left open. Purse-string sutures are painful and not necessa ry. It is not necessary to take a chest radiograph immediately after the drain has been rem oved provided the child is clinically well. \200 Wound care Routine closure of skin wounds in children is by subcuticular suture. The suture runs along below the surface of the wound and provides a neat and water-tight closure. Inv ariably an absorbable suture is used (e.g. Vicryl \204 or PDS \204 ). \200 Dressings are a matter for individual preference. If dressings are used it is wise to keep the wound dry until the dressing is removed. If no dressing is used, then keep the wound dr y for 24 \200\22348hr. The appearance of clean surgical wounds should improve progressively each day after surgery. Parents should be asked to report increasing redness or tenderness so that the wound can be reviewed. \200 Advice after discharge from hospital Parents should be given clear simple advice before dis charge from hospi- tal regarding analgesia, wound care, and post-operative follow-up. Ideal ly, written information should also be provided. \200 Following within 24hr. They should be kept off school for 2 \200\2233 days and be excused s ports activities for 14 days. Routine follow-up of children has now been abandoned by most surgeons. This is, however, a matter of personal preference. Convalescence return to school and resumption of sporting activity depends on the operation. minor day case: children will generally be back to normal following major surgery: speci \201 c advice relating to 23_McClure_23.indd 891 11/14/2012 3:30:27 PM This page intentionally left blank 893 Chapter 24 Special senses Common presentations 894 Hearing assessment 896 Childhood deafness 898 Disorders of the ear 900 Common disorders of the nose 902 Disorders of mouth and tongue 904 Visual development and examination 905 Vision assessment 906 Vision screening in the UK 908 Squints (strabismu s) 910 Ametropia (refractive disorders) 911 Amblyopia 911 Visual impairment 912 Nystagmus 9 13 Disorders of the eye: infection and in \202 ammatory 914 Eye foreign body 916 Cataract 916 Glaucoma 917 Orbit and eyelids 918 Back of the eye problems 920 Trauma 922 24_McClure_24.indd 893 11/14/2012 3:31:57 PM CHAPTER 24 Special senses 894 Common presentations The red eye Careful evaluation is needed when presentation is acute an d there is associated pain, swelling, constant lacrimation, or blurred vision. Causes \200 URTI. \200 Viral conjunctivitis. \200 Irritant conjunctivitis, e.g. chlor inated swimming pool. \200 Bacterial conjunctivitis. \200 Stye (infection of eyelash fo llicle). \200 Chalazion (meibomian or tarsal cyst). \200 Other: uveitis. corneal laceration/ulcer/keratitis; FB; peri-orbital cellulitis; Differential diagnosis \200 Redness of entire eyelid or swollen eyelid: \200 \200 Associated eye pain or constant e ye tearing, blinking: \200 corneal ulcer; \200 HSV keratitis; \200 eye FB ( Blurred v ision: Infant under age 1mth: Painless red eye with good vision: Uncomfortable red eye with good vision: \200 \200 Painful red eye with photophobia: \200 \200 \200 \200 \200 Eyelid redness and oedema: \200 \200 \200 \200 b p.919); peri-orbital cellulitis ( acute ethmoiditis. b p.916). \200 \200 \200 uveitis (b p.915). gonorrhea (b p.914). sub-conjunctival hemorrhage conjunctivitis \200\224viral, bacterial, allergic, or chemical; episcleritis corneal or sub-tarsal FB; corneal abrasion; corneal ulcer/keratitis; anterior uveitis (irit is); scleritis. localized \200\224 generalized \200\224 acute allergic conjunctivitis; herpes simplex/herpe s zoster ophthalmicus. stye, meibomian cyst, dacryocystitis (lacrimal sac abscess); pre-septal or orbital cellulitis; 24_McClure_24.indd 894 11/14/2012 3:31:57 PM COMMON PRESENTATIONS 895 Ear: pain and discharge Ear discharge (otorrhoea) may be due to drainage of blood, ear wax, pus, or \202 uid from the external or middle ear. \200 \200 \200 \200 \200 \200 \200 Otitis externa. Eczema and other skin irritations. Foreign object impaction. Otitis media. Mastoiditis. Perforated eardrum. Head injury \200\224CSF leak. Earache (otalgia) can be a symptom of the conditions noted above. However, it may be the re sult of pain referred from pathology at another location (referred otalgia): \200 \200 \200 \200 \200 Sinusitis Parotitis. Teeth and jaw (impacted molars, dental caries). Acute tonsillitis;. Or opharyngeal tumors. 24_McClure_24.indd 895 11/14/2012 3:31:57 PM CHAPTER 24 Special senses 896 Hearing assessment A fetus will respond to sound in the latter part of pregnancy (from 3rd trimester). At birth, the baby will react to noise with a marked preference for voices. Hearing screening See also b p.560. Speci \201 c screening questions can be asked when evaluating hearing: Birth 12wks: \200 \200 : does baby startle to loud noise? Does baby quieten to mother \200\231s voice even when mother cannot be seen? Does baby quie ten to prolonged loud noise? Does baby settle to a musical toy? \200 5mths: \200 \200 7mths: \200 \200 9mths: \200 \200 11mths: Does baby smile to familiar voice? Does he/she take turns to vocalize when spoken to? Does baby turn to look towards a new sound? Does he/she make tuneful vocalization? Does baby recognize own name? Does baby recognize and react to familiar tunes and music? Will baby react to calling from out of sight? The early detection of hearing loss is important. Deafness impairs speech and language deve lopment, cognitive development, and socialization. A baby who does not startle when parents come into view may not have heard them approach due to deafness. These children need urgen t audio- logical assessment along with children who show absence of appropriate vocalizatio n by age (see bullet points in Hearing screening). Hearing tests All health authority areas in the UK have a universal newborn hearing screeni ng (UNHS) program. UNHS involves otoacoustic emission test- ing in the \201 rst 48hr afte r birth. In the test a small earpiece is inserted into the ear canal. This delivers a sound that evokes an emission from the ear if the cochlea is normal. Current hearing screening programs (Table 24.1) There is currently some regional variation in the type of tests used. In line with recommendations once UNHS is in place, universal distrac- tion testing at 7 \200\2239mths will be abandoned. 24_McClure_24.indd 896 11/14/2012 3:31:57 PM HEARING ASSESSMENT 897 Table 24.1 Hearing screening programs Age Screening test Birth Otoacoustic emission. Auditory brainstem-evoked potential. Auditory response cradle test 6 \200\2239mths Distraction test 18mths to 4yrs Pure tone audiometry (from 3yrs)Speech discrimination test. Impedance audiometry (cid:2)4yrs Pure tone audiometry The distraction test The test is based on the principle that a normal response is observed when sound is presented to an infant, and the infant turns their head to lo- cate the sourc e of the sound. Two testers are required \200\224one presents the sound out of the infant \200\231s line of vision, while the other holds the infant \200\231s attention in a forward direction. The test involves delivering a frequency \200\224 speci \201 c stimulus presen ted at quiet levels (35dB) to the side and slightly behind an infant who is seated on a par ent \200\231s knee. Distraction testing requires a behavioral response and is therefore a direct test of hearin g sensitivity. The major disadvantages of this test are that an infant must be mature enoug h to sit erect and head turn, and it is subject to all the common biases found in behaviora l testing of hearing. It is therefore unsuitable for neonates, which makes identi \201 cat ion of hearing loss before 6mths of age very dif \201 cult. 24_McClure_24.indd 897 11/14/2012 3:31:57 PM CHAPTER 24 Special senses 898 Childhood deafness Hearing loss or deafness may be congenital or acquired and can be divid- ed into sensorineural (SN) or conductive loss. Hearing loss of up to 20dB tends not to aff ect development, but a loss of over 40dB will affect speech and language development. Sensorineural Inherited/genetic \200 \200 Non syndromic. Syndromic: \200 \200 Ushers syndrome (see Table 24.2); Waardenburg syndrome (see Table 24.2). Acquired \200 Perinatal: \200 \200 \200 Postnatal: \200 \200 \200 \200 \200 birth asphyxia; hyperbilirubinemia; congenital infection, e.g. rubella, CMV, syphilis. drugs, e.g. aminoglycosides; meningitis; head injury; labyrinthitis; acoustic neuroma. Conductive External ear abnormalities Ear canal atresia/stenosis. Middle ear abnormalities \200 Acute otitis media. \200 Chronic otitis media (tympanic p erforation, cholesteatoma). \200 Secretory otitis media. 24_McClure_24.indd 898 11/14/2012 3:31:57 PM CHILDHOOD DEAFNESS 899 Table 24.2 Syndromes associated with childhood deafness Syndrome Characteristics Waardenburg SN deafness + pigmentation anomalies (white for lock) Klippel \200\223Feil sequence Deafness (SN or conductive) + short neck with low hair line Treacher \200\223Collins Conductive deafness + midface hypoplasia Pierre \200\223Robin sequence Conductive deafness + mandibular hypoplasia & cleft soft palate Alport SN deafness, pyelonephritis, haematuria, & renal failure Pendred SN deafness + hypothyroidism Usher SN deafness + retinitis pigmentosa Jewel \200\223Lang \200\223Nielson SN deafness + long QT interval on ECG 24_McClure_24.indd 899 11/14/2012 3:31:57 PM CHAPTER 24 Special senses 900 Disorders of the ear See also b pp.280 \200\223283. Otitis media Infection of the middle ear is associated with pain, fever, and irritabil- ity . Examination reveals a red and bulging tympanic membrane with loss of normal light re \202 ex. Occasionally there is acute perforation. Causative organisms include: \200 \200 \200 \200 Viruses. Pneumococcus. B haemolytic streptococcus. Group A . Haemophilus in \202 uenzae Treatment is with broad-spectrum antibiotics (e.g. oral amoxicillin or co-amoxiclav) and an algesia. Decongestants may also help. Complicating mastoiditis (see b p.901) or meningitis are rare. Recurrent ear infections can lead to secretory otitis media. Secretory otitis media \200 This is a middle ear effusion without the symptoms and signs of acute otitis media. It is o ften the result of recurrent episodes of acute otitis media. Duration often last months (ch ronic secretory otitis media) and the effusions may be serous (thin), mucoid (thick), or pu rulent. Children, although asymptomatic, may be noticeably inattentive, or complain of hear ing loss. On examination the drum is retracted and does not move easily. Fluid effusions ma y be visible behind the tympanic membrane, which appears opaque. Chronic (>3mths) secretory otitis media, particularly when associated with suspected hearing loss, needs referral to the audiology and otolaryngology (ear, nose, and throat/ENT) teams for further evaluation a nd possible treatment with myringotomy and insertion of typanostomy ventilation tubes ( \200\230grommets \200\231). \200 Otitis externa \200 Itching of the external ear canal is common in swimmers and after minor trauma. There may b e progressive pain and discharge. Examination reveals an in \202 amed ear canal that may b e oedematous. Treatment is with suction clearance and a combined antibiotic (hydrocortisone 1% + gentamicin 0.3%) and steroid preparation applied topically. \200 \200 Cholesteatoma \200 \200 \200 This is an erosive condition affecting the middle ear and mastoid. It may lead to life-thre atening intracranial infection. Signs include offensive discharge, conductive hearing loss, vertigo, and rarely facial nerve palsy. Urgent referral to the ENT team is required for su rgery and antibiotics. 24_McClure_24.indd 900 11/14/2012 3:31:57 PM DISORDERS OF THE EAR 901 Acute mastoiditis \200 Uncommon, but may follow an episode of acute otitis media. In the early stage symptoms are indistinguishable from those of acute otitis media, but may evolve to include intense pain, swelling, or tenderness over the mastoid process. The latter is due to acute mastoid ostei tis and occurs when infection and destruction of the mastoid bony trabeculae has occurred. Clinical examination may also reveal outward and downward displacement of the pinna, and sw elling of the posterior \200\223superior wall of the external ear canal. Purulent discharge may also be present. Diagnosis is largely clinical, although CT scan is helpful. Urgent re ferral to the ENT team is required for IV antibiotic treatment. Mastoidectomy is sometimes indicated. \200 Foreign body impaction \200 Parents may observe a child putting an object in the ear canal, which otherwise may take se veral days to come to notice. On examination with an auroscope, objects that are easily vis ible (and with a cooperative child) may be extracted using a hook. Use of forceps should be avoided as they tend to push the object further down the ear canal and may damage the tymp anic membrane. Refer to ENT team. Ear malformations \200 Abnormal shape, orientation, or position of the ears should raise suspicions of an underlyi ng congenital or inherited disorder or syndrome. Problems with hearing should also be suspe cted and evaluated. Referral to the clinical genetics team is required. \200 The following conditions are associated with ear malformations. Low set ear position \200 Turner syndrome ( \200 Noonan syndrome ( \200 Rubenstein \200\223Taybi syndrome. \200 Treacher \200\223Collins syndrome ( b p.948). b p.941). b p.950). Malformed auricles \200 \200 \200 \200 b p.950). CHARGE association ( Ehlers \200\223Danlos syndrome (EDS, b p.940). Di George syn drome ( Down syndrome ( b p.946). b p.936). 24_McClure_24.indd 901 11/14/2012 3:31:58 PM CHAPTER 24 Special senses 902 Common disorders of the nose Epistaxis A nose bleed or epistaxis is common in childhood. Th ere is usually no ob- vious precipitating cause, but it may be associated with minor nasal trauma (direct injury). Rarely an underlying coagulation disorder may be present (e.g. acut e lymphoblastic leukemia or hemophilia). Purulent, bloody na- sal discharge should raise su spicions of FB impaction. Initial management should include sitting with the head tilted forwards and applying \201 rm pressure to the cartilaginous part of the nose with \201 nger and thumb for 10 \200 \22315min. If simple measures fail to stop bleeding then referral to the ENT team for nasal packing and cauterization under direct visualization. A blood sample for FBC, clotting scr een, and blood group testing is warranted in this situation. Nasal foreign body \200 Children may present with a unilateral offensive discharge from the nose. Removal of FBs fr om the nose is more urgent than in the ear as the object may be inhaled. Removal may be att empted if the patient is able to cooperate, by having them try to blow their nose. \200 alternatively, attempt removal directly by dislodging with a suitable instrument; an alliga tor type forceps should be used to remove cloth, cotton, or paper FBs; pebbles, beans, and other hard FBs are more easily grasped using bayonet forceps, or they may be rolled out by getting behind it using an ear curette, single skin hook, or right angle ear hook. If these measures are unsuccessful referral to the ENT team is required. Nasal polyps Infrequent in childhood. They are associated with allergic rhinitis or cystic \201 brosis. Signs include clear watery rhinorrhoea, postnasal drip, and nasal obstructio n. Increased snoring intensity may also be a feature. Treatment with topical corticosteroid s (e.g. beclometasone) is required. Nasal malformations Abnormalities in nasal development may be associated with a number of c ongenital or inherited conditions. Here are some examples: Low/depressed nasal bridge \200 \200 \200 \200 b p.967). Achondrogenesis syndromes ( Trisomy 21 ( Fetal valproate syndrome. Mucopolysaccharoidoses ( b p.936). b p.968). 24_McClure_24.indd 902 11/14/2012 3:31:58 PM COMMON DISORDERS OF THE NOSE 903 Broad/wide nasal bridge b p.946). \200 EDS ( \200 Fragile X syndrome ( \200 Waardenbu rg syndrome. b p.943). Small nose \200 \200 \200 \200 b p.948). Cornelia de Lange syndrome ( Fetal alcohol syndrome ( Osteogenesis imperfecta type 2 ( Will iams syndrome (WS, b p.951). b p.762). b p.941). Hypoplastic nares \200 \200 b p.841). Ectodermal dysplasia ( Cleft lip sequence ( b p.846). Prominent nose \200 Cof \201 n \200\223Lowry. \200 Rubenstein \200\223Taybi. \200 Sm ith \200\223Lemli \200\223Opitz. Choanae atresia CHARGE association (b p.950). 24_McClure_24.indd 903 11/14/2012 3:31:58 PM CHAPTER 24 Special senses 904 Disorders of mouth and tongue Gingivostomatitis Gingivostomatitis refers to in \202 ammati on of the oral mucosa and is charac- terized by the presence of multiple sores and mouth ul cers. The condition is common, particularly among pre-school aged children, and is usually secondary to a viral infection, particularly those that cause common child- hood illness su ch as: \200 \200 Herpes simplex (resulting in cold sores and acute herpetic stomatitis). Coxsackie viruses ( hand, foot, and mouth disease, and herpangina). Vesicular lesions may erupt on the lips, gums, tongue, and on the hard palate. There is a w ide spectrum of clinical features ranging from the mild to the severe, which is often chara cterized by: \200 \200 \200 \200 \200 \200 Pain on eating and drinking. High fever. Bleeding from gums. Extensive ulceration of the to ngue, palate, and buccal mucosa. Cervical lymphadenopathy. Dehydration due to refusal to ea t or drink may occur. Investigation Usually no speci \201 c tests are required for the diagnosis. Nevertheless, blood for coxsackie or herpes virus serology and culture of material obtained from the surf ace of the sore may identify the viral infection. Treatment \200 \200 Symptomatic (analgesia) and supportive ( \202 uids). Good oral hygiene should be maintaine d with antiseptic mouth washes where tolerated. Severe infection may need admission for reh ydration with IV \202 uids and treatment with oral or IV aciclovir. Macroglossia Macroglossia is tongue enlargement that leads to functional and cos- metic pro blems. Although this is a relatively uncommon disorder, it may cause signi \201 cant morbi dity. Macroglossia may be congenital or acquired in origin. Congenital \200 \200 \200 b p.936). Down syndrome ( Beckwith \200\223Wiedemann ( Mucopolysaccharidoses ( b p.949). b p.968). Acquired Congenital hypothyroidism (see b p.422). In infants macroglossia poses early dif \201 culty with feeding and, in the longer term, children may need assistance with speech a nd language therapy. 24_McClure_24.indd 904 11/14/2012 3:31:58 PM VISUAL DEVELOPMENT AND EXAMINATION 905 Visual development and examination Normal visual development \200 Vision develops rapidly after birth. By 6wks a baby should have eye contact with the mother when feeding and be able to \201 x and follow a face. Early variable angle squints are c ommon and usually resolve as vision improves and binocular function develops. Congenital oc ular pathology (e.g. dense cataracts) left untreated by 3mths of age will result in permane ntly poor vision. Since the visual system retains its plasticity over the \201 rst 8yrs o f life, any ocular abnormality acquired during this period may also disrupt visual developm ent. Parental concerns about a baby \200\231s vision are usually well founded, so take them seriously. Nystagmus, roving eye movements and/or lack of eye contact warrant referral. Causes of visual impairment in the UK One in 1000 children have visual acuity worse than 6/ 18 in the UK, 70% have an additional disability. Children with visual impairment should rec eive early specialist educational and mobility support. Causes of visual impairment Prenatal (50%) \200 \200 \200 Genetic/hereditary (e.g. Down, retinal dystrophies, cataract) Hypoxia/ischaemia Infection/d rugs (e.g. CMV, rubella) Peri/neonatal (30%) \200 Hypoxia/ischaemia (e.g. cerebral visual impairment and retinopathy of prematurity) Infectio n NAI \200 Childhood (20%) \200 \200 \200 \200 \200 Tumor (e.g. retinoblastoma, craniopharyngioma) Raised ICP Hypoxia/ischaemia Accidental and NAIs Speci \201 c systemic disorders (e.g. uveitis) 24_McClure_24.indd 905 11/14/2012 3:31:58 PM CHAPTER 24 Special senses 906 Vision assessment Early visual development At birth most babies can \201 x and follow hor izontally. Initially, the eyes move independently and infant may appear to \200\230squint \200\231. Visual acuity is about 6/200. Retina is well developed, but the fovea is immature . Development of visual acuity is dependent on the production of well-formed images on the retina. A cataract will affect normal development of the optic pathway and visual cortex. L ack of normal development leads to amblyopia. \200 \200 6wks: 3mths: toys. 6mths: other. both eyes move together and will follow a light source. visual acuity is 6/60. A baby shoul d watch their hands and notice a baby reaches for toys and passes them from one hand to the Vision screening Assessment for visual problems should be performed on all children at the newborn examination, the 6 \200\2238wks review, and the pre-school (or school- entry) visio n check (see b p.908). Vision assessment Birth \200 \200 General observation: Ophthalmoscopy: Red re \202 ex \200\224dark spots in the red re \202 ex can be due to cataracts, \200 corneal abnormalities, or opacities in the vitreous . The red re \202 ex may be absent with a dense cataract White re \202 ex retinopathy of prematurity eye movements \200\224present with cataracts, retinoblastoma, or 6 \200\2238wks Optokinetics (e.g. nystagmus demonstrated by looking at a mov- ing, striped target) 2yrs Identi \201 cation of pictures 3yrs Letter matching on the single letter chart, e.g. Sheridan Gardiner chart 5yrs Identi \201 cation of letters on the Snellen chart If the following are evident at the age of 6mths, it should arouse sus- picions: \200 \200 \200 Lack of eye contact/visual inattention Random eye movements Persistent nystagmus or squint (see b p.910) 24_McClure_24.indd 906 11/14/2012 3:31:58 PM VISION ASSESSMENT 907 24_McClure_24.indd 907 11/14/2012 3:31:58 PM CHAPTER 24 Special senses 908 Vision screening in the UK Neonatal examination \200 To detect congenital ocular abnormalities, e.g. cataract, corneal opacities, microphthalmia , glaucoma and retinoblastoma. Ask about family history of these disorders. Use a (bright) ophthalmoscope to examine the eye and red re \202 ex. An indistinct red re \202 ex can be caused by cataracts/corneal opacities. Retinoblastoma or abnormal retina can cause a white re \202 ex. The red re \202 ex may be darker in Asian and Afro-Caribbean babies. Refer o n if in doubt. \200 \200 \200 \200 \200 Community screening \200 At 6wks : GP asks parents about their baby \200\231s visual behavior. Baby should be able t o \201 x and follow a face and large toy. Red re \202 exes checked with an ophthalmoscop e. Squint assessment. At 7 \200\2238wks what to look for regarding expected future visual d evelopment. At 4 \200\2235yrs : orthoptist checks monocular visual acuity and ocular alignm ent, children achieving <6/9.5 are referred. : health visitor observes visual behavior. Parents advised of Secondary screening Orthoptic program for children referred by par- ents, health visitors a nd GPs whenever a concern regarding vision or squint is raised. Eye examination techniques Visual examination \200 \200 \200 \200 \200 : baby should \201 x and follow a bright target and your face. 6 \200\2238wks 4mths 6mths: 2 \200\2233yrs: 4 \200\2235yrs : baby should not squint and should \201 x and follow toys. baby should reach out for toy s. use picture charts (e.g. Kays pictures). : use letter charts (e.g. Snellen +/ \200\223 m atching letter card). Eye movements \200 Use a bright toy to attract attention and move in a \200\230H \200\231 shape to assess the action of each muscle. Cover test for squint assessment (see Fig. 24.1). Anterior segment examination \200 Use ophthalmoscope set on +20 for a magni \201 ed view of the front of the eye, click in t he cobalt \201 lter for \202 uorescein examination. Instill anesthetic drops prior to e xamination if the child is in pain. Check the diameter of the corneas are equal and that th e light re \202 ection from each is bright. Check the red re \202 ex in both eyes is equa lly bright. \200 Posterior segment examination \200 Ask the child to look at an interesting target over your shoulder when trying to examine th e optic disc. Dilating drops are safe to use, but will interfere with neuro- observations f or 24hrs: use 1% cyclopentolate (if <1yr old use 0.5%). 24_McClure_24.indd 908 11/14/2012 3:31:58 PM VISION SCREENING IN THE UK 909 a) Pseudosquint: broad epicanthic folds give the appearance of squint, but the corneal refl ections are symmetrical b) Cover test: when a cover is placed over the fixing eye, the squinting eye moves to take up fixation: Left Esotropia Left exotropia c) Uncover/alternating cover test: the eyes initially appear aligned, but when one eye is c overed a latent squint will cause the eye under the cover to deviate. A movement to regain fixation is seen when the cover is removed. Esophoria Exophoria Fig. 24.1 Cover testing. 24_McClure_24.indd 909 11/14/2012 3:31:59 PM CHAPTER 24 Special senses 910 Squints (strabismus) Squints are common in childhood. They occur with misalignment of the v isual axes of the two eyes so that they appear to point in different direc- tions. If a squ int develops in the \201 rst 7yrs, it can have a signi \201 cant impact on visual develo pment. The causes of squint may be: Idiopathic. Refractive error. Visual loss. Ophthalmoplegia (ce ntral or peripheral). \200 \200 \200 Types of squint There are two main types. Concomitant (non-paralytic) squint \200 \200 Common and usually due to a refractive error in one or both eyes. Often convergent. Non-concomitant (paralytic) squint \200 \200 Rare and usually due to cranial (motor) nerve palsy. Must exclude an intracranial lesion (e .g. brain tumor). Describing squints Squints are described using the following terminology. \200 \200 \200 bad eye turned inwards (cross-eyed appearance) Convergent: Divergent: Latent: a squint that is controlled by subconscious effort and is no t always apparent. In certain situations, such as fatigue, the control is lost and the squi nt will become \200\230manifest \200\231 Pseudosquint: appearance of a squint, which is ex cluded on testing bad eye turned outwards this arises when wide epicanthic folds give the Testing squints All squints should be examined using the \200\230cover test \200\231 (see Fig. 24.1). Management The aim of treatment is to get the \200\230weaker \200\231 squinting eye \200 \230trained up \200\231 in order to prevent amblyopia. Treatments are usually under the sup ervision of orthoptists in co-operation with ophthalmic surgeons. \200 \200 \200 \200 Correct refractive error: wear glasses. Eye patch wearing on the good eye to \200\230train \200\231 weaker eye. Eye muscle exercises. Eye (muscle) surgery if large squint and above measures failing. Note: A child must be seen by an ophthalmologist if squint is: \200 \200 \200 Divergent Paralytic Persistent beyond age of 2mths 24_McClure_24.indd 910 11/14/2012 3:31:59 PM AMETROPIA (REFRACTIVE DISORDERS) 911 Ametropia (refractive disorders) To see clearly the image must be focused on the retina. In myopia (short/ near sight) the image is focused in front of the retina and in hypermetropi a (long/far sight) the image is focused behind the retina. Astigmatism results from uneven focusing power at different meridians, causing image distor- tion. Children are usually bor n a little long-sighted and the refraction nor- malizes as the eyes grow. Ametropia may lea d to squints and amblyopia. Quick rule of thumb: convex lenses (for long sight) magnify; co ncave lenses (for short sight) minify an image. Amblyopia Permanent loss of visual acuity in an eye that has not received clear im- ages in the sensitive period of visual development (up to age 7yrs). Most commonly due to squint, but may also develop with refractive errors and cataracts. Management Regular orthoptic monitoring with ongoing correction of the refractive error in the \200\230lazy \200\231/weaker eye is required. \200 \200 Correct refractive error: Eye patching: to force the \200\230lazy eye \200\231 to work. Ey e (muscle) surgery. with glasses. attempt to reverse amblyopia, by covering the better eye 24_McClure_24.indd 911 11/14/2012 3:31:59 PM CHAPTER 24 Special senses 912 Visual impairment Severe visual impairment in 1/1000 births. 50% of severe visual impairmen t is genetic: \200 \200 \200 Identify causes amenable to treatment (e.g. congenital cataracts). Use non-visual stimulati on (e.g. touch, speech) to aid development. Provide a safe environment. A child is registered blind when the best-corrected vision is less than 3/60. The criterion for partial sight registration is a visual acuity better than 3/60, but less than 6/60. Causes of visual impairment Inherited/genetic (50%) \200 \200 b p.936). Trisomy 21 ( CHARGE association ( b p.950). Congenital \200 \200 \200 \200 \200 b p.916). Cataract ( Albinism. Retinal dystrophy. Retinoblastoma ( Congenital infection, e.g. CMV, ru bella ( b p.664). b p.182). Antenatal/perinatal (30%) \200 \200 \200 \200 b pp.188, 920). Retinopathy of prematurity ( Hypoxic ischaemic encephalopathy ( Cerebral damage. Optic nerv e hypoplasia. b p.172). Postnatal (20%) \200 \200 \200 Trauma. Infection, e.g. ophthalmic herpes simplex. Juvenile idiopathic arthritis: iritis (b pp.768, 915). Delayed visual maturation Delayed visual maturation Babies with delayed visual maturation ( DVM) appear blind in the \201 rst few months, but their visual behavior improves with age . There are 3 forms: \200 Isolated DVM: and full development of vision between 3 \200\2236mths of age. Motor developm ent may also be delayed. DVM associated with cerebral visual impairment cerebral palsy may initially appear blind. The vision usually improves over years, but may be impaired. DVM as sociated with ocular disease: cataracts, and nystagmus can interfere with early visual deve lopment. Vision improves over years, but with residual de \201 cit. there is no underlying pathology and there is a rapid : e.g. infants with congenital ocular disease, e.g. Children with DVM should be monitored for general developmental issues. Visual impairment t eachers should be involved to help parents to stimulate visual development. 24_McClure_24.indd 912 11/14/2012 3:31:59 PM NYSTAGMUS 913 Nystagmus Nystagmus is an involuntary rhythmic oscillation of one or both eyes (see Table 2 4.2). The direction of the fast phase, the frequency and amplitude of the nystagmus should be noted. Acquired nystagmus always requires investigation (neuro-imaging and/or electrophy siology). Nystagmus may also occur if there is muscle paralysis or weakness (e.g. secondary to myasthenia gravis) (see b p.544). Table 24.2 Types and patterns of nystagmus Type Pattern/cause Congenital motor nystagmus Horizontal jerk Sensory nystagmus (poor vision) Usually horizontal jerk Vestibular nystagmus Horizontal jerk Neurological nystagmus Jerk nystagmus beats towards and worse on lateral gaze Gaze paretic High frequency, low amplitude, any direction. Seen in white matter disorders Pendular Seen with posterior fossa disorders, e.g. downbeat with Arnold-Chiari malformation Upbeat/downbeat One eye elevates while the other depresses,: midline disorders/para-sellar masses See-saw Opsoclonus/ocular \202 utter Bursts of high frequency saccades in all directions, e.g. opsoclonus-myoclonus syndrome 24_McClure_24.indd 913 11/14/2012 3:31:59 PM CHAPTER 24 Special senses 914 Disorders of the eye: infection and in \202 ammatory Eye infections are common in childhoo d and largely due to bacterial or viral infections affecting the conjunctiva. Neonatal conjunctivitis \200\230Sticky eyes \200\231 Common in the neonatal period startin g from the 3rd or 4th day. Swabs are usually negative for signi \201 cant pathogens. Simpl e cleaning measures are usually suf \201 cient. Bacterial infection with either Staphyloco ccus aureus, Pseudomonas aeruginosa, or streptococcal pathogens can occur. (See also b p.14 6). Treatment Topical antibiotic ointment is indicated, e.g. neomycin. Gonococcal conjunctivitis Should be suspected if purulent discharge with swelling of the ey elids oc- curs within the \201 rst 48hr of life. Treatment IV antibiotics required, e.g. cephalosporin. Chlamydial conjunctivitis Usually presents at the end of the \201 rst week of life. Diagn osis established by speci \201 c monoclonal antibody test performed on conjunctival secre- tions. Treatment Two-week course of oral erythromycin or topical tetracycline eye ointment is requ ired. Childhood conjunctivitis May be due to bacteria (e.g. Gram +ve cocci or Haemophilus in \202 uenzae), virus (e.g. adenovirus), or to allergic reaction. Treatment Speci \201 c antibiotic eye drops or ointment (e.g. fusidic acid or gentamicin) for 5 days is required. Allergic conjunctivitis Acute allergic conjunctivitis can cause rapid onset lid swelling an d chemo- sis (conjunctival oedema). Seasonal/perennial forms present with other features of atopy. Vernal kerato-conjunctivits is a chronic allergic con- junctivitis which is painful and can cause photosensitivity due to corneal involvement. Topical mast cell stabilizers a nd antihistamines can improve symptoms. Topical steroids are occasionally necessary, but sh ould only be prescribed by a specialist. 24_McClure_24.indd 914 11/14/2012 3:31:59 PM DISORDERS OF THE EYE: INFECTION AND INFLAMMATORY 915 Peri-orbital cellulitis See b pp.718, 919 Keratitis Keratitis is an in \202 ammation or in fection of the cornea, which can lead to corneal scarring and requires urgent specialist ma nagement. Symptoms in- clude FB sensation, pain, and photophobia with a red eye. It can occ ur due to viral infection, e.g. HSV or adenovirus in conjunction with skin lesions or conju nctivitis. Bacterial keratitis can occur secondary to corneal exposure in the hospital sett ing or secondary to contact lens use. Staphylococcal hypersensitivity is a common cause of keratitis in children with blepharitis. Keratitis can also occur as a toxic effect of chemo therapy. Iritis Also known as anterior uveitis. Refers to in \202 ammation of the uveal tract struc tures (i.e. iris, ciliary body, and choroids). It is characterized by symp- toms of: \200 \200 \200 \200 Ocular pain. Photophobia. Excessive lacrimation. Blurred vision. Signs include: \200 Redness. \200 Miosis. \200 Keratic precipitates on ophthalmoscopi c examination. Long-term disease may be complicated with the development of cataract, glaucoma, and macula r eye degeneration. Causes of iritis \200 \200 \200 e.g. herpes simplex/zoster. Local infection: Trauma or surgery. Systemic disease: \200 Seronegative arthritides \200\224 Reiter \200\231s syndrome, psoriatic arthritis (b pp.777 \200\223779). b p.332). \200 IBD ( \200 b p.768). JIA ( \200 Sarcoidosis. \200 Beh et \200\231s disease. HLA-B27 positive, ankylosing spondylitis, Management Referral to the ophthalmologists and treatment with topical steroid drops/ointme nt and mydriatic agents are required. 24_McClure_24.indd 915 11/14/2012 3:31:59 PM CHAPTER 24 Special senses 916 Eye foreign body Small FBs are usually cleared by tear \201 lm. Occasionally they may lod ge underneath the upper eyelid or become embedded in the cornea caus- ing intense irritatio n and excessive lacrimation. Examination of the eye to locate and remove the FB should be c arried out. \200 \200 Instill topical anesthetic drops. Perform a visual acuity check (where appropriate) and fun doscopy \200\224 examine the anterior chamber and tear \201 lm with a bright light (best done with a slit lamp) and examine the conjunctival sacs. A loose FB usually adheres to a s wab lightly touched to the surface of the conjunctiva, or will be washed out by copious irr igation with saline. Referral to the ophthalmology team to exclude any corneal abrasion cau sed by the FB is usually required. Cataract This refers to an opaci \201 cation of the lens. It may be congenital or ac- quir ed. Causes of cataract \200 Inherited/genetic: \200 \200 Congenital maternal infection: T rauma. Radiotherapy. In \202 ammation: Infection. Metabolic syndromes: \200 galactosaemi a( \200 Wilson \200\231s disease ( \200 Lowes \200\231; \200 Fabry \200\231s ( Other syndromes: Drugs: myotonic dystrophy; Walker-Warburg syndrome. \200 \200 \200 \200 \200 e.g. rubella, toxoplasmosis (b p.182). e.g. chronic iritis. b p.967); b p.976); b p.968). \200 e.g. trisomy 21. e.g. long-term steroid therapy. Absence of the normal bilateral red re \202 ex, or the presence of a white re \202 ex on ophthalmoscopic examination, should raise suspicion of an underlying cataract and immediate referral to an ophthalmologist is required. 24_McClure_24.indd 916 11/14/2012 3:31:59 PM GLAUCOMA 917