Ординатура / Офтальмология / Английские материалы / Comprehensive Ophthalmology_Khurana_2007

What is the difference in the power of an anterior chamber IOL versus posterior chamber IOL ?

Equivalent power of an anterior chamber IOL is less (say about +18D) than that of posterior chamber IOL (+20D).

Surgical management of cataract

For questions related to surgical management of a cataract patient, see page 587.

GLAUCOMA

A CASE OF PRIMARY NARROW ANGLE GLAUCOMA

CASE DESCRIPTION

Age and sex. Primary narrow-angle glaucoma usually presents between 50 and 60 years of age. It occurs more commonly in females than males in a ratio of 4:1. Presenting symptoms depend upon the stage of the disease as follows:

1. Latent glaucoma (Primary angle-closure glaucoma suspect). Patient does not present in this stage as there are no symptoms. Latent primary angle-closure glaucoma is diagnosed:

On routine slit-lamp examination in patients presenting with some other eye disease, and

In fellow eye of the patients presenting with subacute or acute angle-closure glaucoma.

2.Intermittent glaucoma (Subacute glaucoma).

Patient presents with transient blurring of vision, coloured haloes around the light due to corneal oedema and mild headache. These symptoms are due to transient rise in intraocular pressure (IOP) and occur in intermittent attacks at irregular intervals. The attacks are usually precipitated by overwork in the evening, anxiety and fatigue.

3.Acute congestive glaucoma (acute angleclosure glaucoma). Patient presents with an attack of sudden onset of very severe pain in the eye which radiates along the branches of fifth nerve. Frequently there is history of associated nausea, vomiting and prostrations. There is history of rapidly progressive loss of vision, redness, photophobia and watering. About 5 per cent patients give history of typical previous intermittent attacks.

4.Chronic congestive glaucoma. Patients have dull and constant pain in the eye along with marked diminution of vision. Patients usually give history of preceding attack of acute congestive glaucoma or repeated attacks of intermittent glaucoma.

5.Absolute glaucoma. Such patients present with:Pain in the eye which is severe and irritatingConstant headache

Watering and redness of the eye

Complete loss of vision (no perception of

light)

This stage results if the chronic phase is left untreated.

Ocular examination. The signs observed on ocular examination depend upon the stage of glaucoma (See page 225-231):

1.Latent glaucoma (prodromal stage). The eye is white and quiet. Anterior chamber is shallow. Gonioscopy reveals narrow angle. IOP is usually normal.

2.Intermittent glaucoma (subacute glaucoma).

Usually the patient presents after the attack is over and eye looks normal except for a shallow anterior chamber and narrow angle (on gonioscopy)

3.Acute congestive glaucoma. Signs are as follows:

Lids may be oedematous

Conjunctiva is chemosed, and congested, (both conjunctival and ciliary vessels are congested).

Cornea becomes oedematous and insensitive.

Anterior chamber is very shallow. Aqueous flare or cells may be seen in anterior chamber.

Angle of anterior chamber is completely closed as seen on gonioscopy.

Iris may be discolored.

Pupil is semidilated, vertically oval and fixed. It is non-reactive to both light and accommodation.

IOP is markedly elevated, usually between 40 and 70 mm of Hg.

Optic disc is oedematous and hyperaemic.

Fellow eye shows shallow anterior chamber and a narrow angle.

4.Chronic closed-angle glaucoma. Signs are as follows:

The IOP remains constantly raised.

The eye remains permanently congested and irritable, except in cases where chronic closed

angle glaucoma results due to gradual creeping synechial angle closure. (In such cases, eye is painless and white like primary open-angle glaucoma).

Visual field defects appear which are similar to those in POAG.

Optic disc may show glaucomatous cupping (Pl.III.5).

Visual acuity is decreased.

Gonioscopy reveals angle closed by peripheral anterior synechiae.

5.Absolute glaucoma. Signs are as follows:

Lids show mild oedema.

Palpebral aperture is slightly narrow.

The anterior ciliary veins are dilated with a slight ciliary flush around the cornea (perilimbal reddish blue zone).

In long-standing cases, few prominent and enlarged vessels are seen in the form of ‘caput medusae’.

Cornea in early cases is clear but insensitive. Slowly it becomes hazy and may develop epithelial bullae (bullous keratopathy) or filaments (filamentary keratitis).

Anterior chamber is very shallow.

Iris becomes atrophic.

Pupil becomes fixed and dilated and gives a greenish hue.

Optic disc shows glaucomatous optic atrophy.

Intraocular pressure is high; eyeball becomes stony hard.

A CASE OF PRIMARY OPEN-ANGLE GLAUCOMA

CASE DESCRIPTION

An early case of primary open-angle glaucoma (POAG) is usually not given in undergraduate examinations. However, an advanced or a case of POAG which has been operated for trabeculectomy may be kept as short or long case.

Age and sex. POAG usually affects about 1 in 100 of the general population (of either sex) above the age of 40 years. The disease is essentially bilateral.

Presenting symptoms. The disease is insidious and usually asymptomatic. Mild symptoms experienced by the patients include:

Mild headache and eyeache.

Difficulty in reading (patients usually give history of frequent change in near vision glasses).

Occasionally an observant patient may notice a defect in the visual field (scotoma).

In late stages patient may complain of delayed dark adaptation.

Ocular examination. Anterior segment is usually normal. In advanced cases the pupils are sluggishly reacting. Fixed and dilated pupils are seen in absolute glaucoma. Diagnosis is usually made from triad of raised intraocular pressure (IOP), glaucomatous optic disc changes and visual field changes (see pages 215-220) In a case of POAG operated for trabeculectomy, a filteration conjunctival bleb is seen at the site of operation near the limbus.

A CASE OF PHACOMORPHIC GLAUCOMA

Presenting symptoms. Patient presents with a sudden onset of severe pain, redness, watering from the eyes and marked loss of vision. Usually there is associated nausea, vomiting, headache and prostration. Patient always gives history of preceding gradual painless loss of vision.

Ocular examination reveals following signs (Fig.9.20):

Lids may be oedematous.

Conjunctiva is chemosed and congested (both conjunctival and ciliary vessels are congested).

Cornea becomes oedematous and insensitive.

Anterior chamber is very shallow (opposite eye normal). Aqueous flare and cells may be seen in the anterior chamber

Pupil is semidilated, vertically oval and fixed.

Lens is cataractous, swollen and bulging forward (intumescent cataract).

IOP is markedly elevated.

A CASE OF PHACOLYTIC GLAUCOMA

CASE DESCRIPTION

The presenting symptoms and signs are similar to phacomorphic glaucoma except for following differences:

Anterior chamber is not shallow. It is normal or slightly deep. Aqueous is turbid.

Lens shows hypermature Morgagnian senile cataract.

RELATED QUESTIONS

What are normal values of intraocular pressure?

Range: 10 to 21 mm of Hg

Mean: 16 ± 2.5 mm of Hg

What is the normal amount of aqueous humour present in the eye ?

Normal amount of aqueous humour present in the anterior chamber is about 0.25 ml and in posterior chamber is 0.06 ml.

What is the normal rate of aqueous production?

2.3 µl/minute.

What is the site of aqueous production?

Ciliary processes.

Name the mechanisms concerned with aqueous production?

Diffusion

Ultrafiltration

Active secretion

Define glaucoma.

Glaucoma is not a single disease but a group of disorders in which intraocular pressure is sufficiently raised (above the tolerance limit of the affected eye) to impair normal functioning of the optic nerve.

How do you classify glaucoma?

I.Congenital/developmental glaucomas

1.Primary congenital glaucoma (without associated anomalies)

2.Developmental glaucoma with other

associated anomalies

II.Primary glaucoma

1.Primary open-angle glaucoma (POAG)

2.Primary angle-closure glaucoma (PACG)

3.Primary mixed mechanism glaucoma

III. Secondary glaucomas

What is the incidence of primary angle-closure glaucoma ?

1 in 1000 people over 40 years

Male to female ratio is 1:4

Name the predisposing factors for PACG.

Hypermetropic eyes

Small corneal diameter

Relative large size of the crystalline lens

Short axial length of eyeball

Shallow anterior chamber

Plateau iris configuration

Name the precipitating factors for an attack of acute congestive glaucoma.

Dim illumination

Emotional stress, anxiety and excitement

Use of mydriatics

Describe the mechanism of rise in IOP in acute narrow-angle glaucoma.

Mid-dilated pupil — increased contact between the lens and relative iris pupil block – physiological iris bombe formation — appositional angle closure (causing transient rise in IOP) — synechial angle closure — prolonged rise in IOP.

Name the clinical stages of primary angle-closure glaucoma.

1.Latent primary angle-closure glaucoma

2.Intermittent or subacute glaucoma.

3.Acute angle-closure (acute congestive) glaucoma

4.Chronic angle-closure glaucoma

5.Absolute glaucoma.

Name the provocative tests used in latent or subacute glaucoma stage to confirm the diagnosis.

1.Darkroom test

2.Prone test

3.Prone darkroom test

4.Mydriatic test (10% phenylephrine test)

5.Mydriatic-miotic test (10% phenylephrine and 2% pilocarpine test)

Enumerate the sequelae of an attack of acute narrow-angle glaucoma.

Sectoral iris atrophy

Spiralling of iris fibres

Iris hole (pseudopolycoria)

Large irregular pupil

Glaucomflecken

Peripheral anterior synechiae

Chronic corneal oedema

How will you treat a case of acute narrow angle glaucoma?

I.Immediate medical treatment to control pain and lower the intraocular pressure

1.Injectable analgesic to relieve the severe pain

2.Acetazolamide 500 mg stat and then 250 mg qId orally.

3.Hyperosmotic agents, e.g., glycerol 1to 2 g per kg body weight orally in lemon juice and/or mannitol 1to 2g per kg body weight (20% solution) IV over 30 minutes

4.Pilocarpine eyedrops 2 to 4 per cent every 15 minutes for one hour and then qId

5.0.5 per cent timolol maleate eyedrops bd

6.Topical steroid 3 to 4 times a day to control the inflammation

II.Surgical treatment

1.Peripheral iridectomy/laser iridotomy is sufficient when peripheral anterior synechiae (PAS) are formed in less than 50 percent of the

Grade 0 (Closed angle)

Angle width is 0°

None of the angle structures are seen (iridocorneal contact)

Completely closed angle

Name the structures forming aqueous outflow system.

1.Trabecular meshwork

2.Schlemm’s canal

50 percent of the angle

3.Peripheral iridectomy/laser iridotomy should also be considered as prophylaxis for the fellow eye.

developmental glaucoma?

Affects 1 in 10,000 live births

Male to female ratio is 3:1.

What is the pathogenesis of developmental

Name the structures forming angle of the anterior chamber.

1.Root of the iris

2.Anterior most part of the ciliary body

3.Scleral spur

4.Trabecular meshwork

5.Schwalbe’s line (prominent end of Descemet’s membrane of cornea).

How will you grade the angle width gonioscopically?

Shaffer’s grading system is as follows: Grade 4 (Wide open angle)

Angle width is 35°-45º

Structures seen are from Schwalbe’s line to ciliary body

Closure impossible

Grade 3 (Open angle)

Angle width is 20°-35°

Structures seen are from Schwalbe’s line to scleral spur

Closure impossible

Grade 2 (Moderately narrow angle)

Angle width is about 20°

Structures seen are from Schwalbe’s line to trabecular meshwork

Angle closure is possible but unlikely Grade 1 (Very narrow angle)

Angle width is about 10°

Structure seen is Schwalbe’s line only

High-angle closure risk

glaucoma?

Failure in the absorption of mesodermal tissue resulting in failure of development of the angle structures.

What are gonioscopic findings of developmental glaucoma ?

Barkan’s membrane may be present

Thickening of trabecular meshwork

Insertion of iris above the scleral spur

Peripheral iris stroma hypoplasia

What is buphthalmous ?

This term is used when eyeball enlarges (corneal diameter becomes more than 13 mm) in children developing congenital glaucoma at an early age (before the age of 3 years).

What is the treatment of primary congenital glaucoma?

1.Goniotomy

2.Trabeculotomy

3.Trabeculectomy (with antifibrosis treatment)

What are the causes of secondary congenital glaucoma?

I.Glaucoma associated with mesodermal dysgenesis of the anterior ocular segment, e.g.:

1.Posterior embryotoxon

2.Axenfeld’s anomaly

3.Rieger’s syndrome

4.Peter’s anomaly

II. Glaucoma associated with aniridia (50%)

III.Glaucoma associated with ectopia lentis syndrome

1.Marfan’s syndrome

2.Weill-Marchesani’s syndrome

3.Homocystinuria

IV. Glaucoma associated with phacomatoses:

1.Sturge-Weber syndrome (50% cases)

2.Von Recklinghausen’s neurofibromatosis (25% cases)

V. Miscellaneous conditions

1.Lowe’s syndrome (50% cases)

2.Naevus of Ota

3.Nanophthalmos

4.Congenital microcornea (60%)

5.Congenital rubella syndrome (10% cases).

What is the incidence of primary open-angle glaucoma?

It affects 1 in 100 population (of either sex) above the age of 40 years.

It forms about one-third cases of all glaucomas.

What are the features of glaucomatous cupping of the disc?

These include (Fig.9.9 & 9.10) the following:

1.Cup/disc ratio is increased (normal 0.3 to 0.4), asymmetry of more than 0.2 is suspicious

2.Notching of the rim

3.Nasal shift of the vessels at disc

4.Pallor area on the disc

5.Presence of splinter haemorrhages on or near the disc margin

Name the predisposing factors for POAG.

1.Heredity (positive family history)

2.Age (between 5th and 7th decade)

3.High myopia

4.Diabetes mellitus

What is the characteristic triad of POAG?

1.Intraocular pressure more than 21 mm of Hg

2.Glaucomatous cupping of the disc

3.Glaucomatous field defects

What is ocular hypertension ?

Ocular hypertension or glaucoma suspect is the term used when a patient has an IOP constantly more than 23 mm of Hg but no optic disc or visual field changes.

What is low-tension glaucoma (LTG)?

This term is used when typical glaucomatous disc cupping with or without visual field changes is associated with an IOP constantly below 21 mm of Hg.

What are the other ocular associations of POAG?

1.High myopia

2.Fuchs’ dystrophy

3.Retinitis pigmentosa

4.Central retinal vein occlusion (CRVO)

5.Primary retinal detachment

What are glaucomatous field defects ?

1.Baring of the blind spot

2.Paracentral scotoma in Bjerrum’s area (an arcuate area extending above and below the blind spot to between 10° and 20° of fixation point)

3.Seidel scotoma

4.Arcuate or Bjerrum’s scotoma

5.Double arcuate scotoma

6.Roenne’s central nasal step

7.Advanced field defects with tubular vision

What is the treatment for primary open-angle glaucoma?

1.Medical treatment: It is still the initial therapy. Topical timolol maleate 0.25 per cent BD which may be increased to 0.5 per cent BD Pilocarpine TDS 2 per cent which may be increased to 4 per cent BD. was previously used as drug of second choice. Recently latanoprost (0.005%, OD) is being considering the drug of first choice (provided patients can afford to buy it. Dorzolamide (2%, 2- 3 times/day) has replaced pilocarpine as the second drug of choice and even as adjunct drug. If the patient does not respond to a single drug the two drugs can be combined. If still the IOP is not controlled, tablet acetazolamide 250 mg TDS may be added.

2.Argon laser trabeculoplasty: It may be considered as an alternative to medical therapy or as an additional measure in patients not responding to medical therapy alone.

3.Surgical therapy: It is usually undertaken when patient does not respond to maximal medical therapy alone or in combination with laser trabeculoplasty. Recently it is also being considered as the primary line of treatment. Surgical treatment mainly consists of filtration surgery trabeculectomy.

What are secondary glaucomas ?

In secondary glaucomas, intraocular pressure is raised due to some other primary ocular or systemic disease.

Depending upon the causative primary disease, secondary glaucomas are classified as follows:

1.Lens-induced glaucomas

2.Glaucomas associated with uveitis

3.Pigmentary glaucoma

4.Neovascular glaucoma

5.Pseudoexfoliative glaucoma (glaucoma capsulare)

6.Glaucomas associated with intraocular haemorrhages

7.Steroid-induced glaucoma

8.Traumatic glaucoma

9.Glaucoma in aphakia

10.Glaucoma associated with intraocular tumours

11.Glaucomas associated with iridocorneal endothelial (ICE) syndromes

12.Ciliary block glaucoma (malignant glaucoma)

What are lens-induced glaucomas?

1.Phacomorphic glaucoma: Herein IOP is raised due to secondary angle closure and/or pupil block by:

Intumescent (swollen) cataractous lens (Fig.9.20)

Anterior subluxated lens

Spherophakia

2.Phacolytic glaucoma: Here in IOP is raised due to clogging of trabecular meshwork by the macrophages laden with the leaked lens proteins, usually in hypermature cataract.

3.Lens particle glaucoma: It occurs due to blockage of trabeculae by the lens particles following rupture of the lens or after ECCE.

4.Phacoanaphylactic glaucoma: Sensitization of eye or its fellow to lens proteins. Inflammatory material clogs trabecular meshwork.

5.Phacotoxic glaucoma: Herein IOP is raised due to lens matter induced uveitis.

What is malignant glaucoma ?

Malignant or ciliary block glaucoma occurs rarely as a complication of any intraocular operation. Classically, it occurs following peripheral iridectomy or filtration operation for primary narrow angle glaucoma. Its pathogenesis includes cilio-lenticular or ciliovitreal block.

It is characterized by a markedly raised intraocular pressure, persistent flat anterior chamber and a negative Seidel’s test.

What is differential diagnosis of acute congestive glaucoma?

Acute conjunctivitis

Acute iridocyclitis

Secondary acute congestive glaucomas

–Phacomorphic glaucoma

–Phacolytic glaucoma

–Glaucomatocyclitic crisis

What is post-inflammatory glaucoma ?

Postinflammatory glaucoma refers to rise in intraocular pressure due to following complications of anterior uveitis:

Annular synechiae

Occlusio pupillae

Angle closure following iris bombe formation

Angle closure due to organization of the inflammatory debris

What is pigmentary glaucoma?

Pigmentary glaucoma refers to raised IOP in patients with pigment dispersion syndrome. It typically affects young myopic males. Its features are similar to POAG with associated pigment deposition on corneal endothelium (Krukenberg’s spindle) trabecular meshwork, iris, lens and zonules.

What is neovascular glaucoma?

Neovascular glaucoma refers to raised IOP occurring due to formation of a neovascular membrane involving angle of the anterior chamber. Usually, stimulus to new vessel formation is retinal ischaemia as seen in diabetic retinopathy, CRVO, Eales’disease. Other rare causes are chronic uveitis, intraocular tumours, old retinal detachment, CRAO and retinopathy of prematurity.

What is pseudoexfoliation glaucoma ?

Pseudoexfoliation glaucoma is a type of secondary open-angle glaucoma associated with pseudoexfoliation (PEX) syndrome. PES refers to amyloid like deposits on pupillary border, anterior lens surface, posterior surface of iris, zonules and ciliary processes.

What is steroid-induced glaucoma?

Steroid-induced glaucoma is secondary open-angle glaucoma having features similar to POAG. It probably occurs due to deposition of mucopolysaccharides in the trabecular meshwork in patients using topical steroid eyedrops. Roughtly 5 per cent of general population is high steroid responder (develop marked rise of IOP after about 6 weeks of steroid therapy), 35 per cent are moderate and 60 per cent are nonresponders.

Enumerate the causes of glaucoma in aphakia.

Raised IOP due to postoperative hyphaema, inflammation, vitreous filling the anterior chamber.

Angle closure due to flat anterior chamber

Pupil block with or without angle closure

Undiagnosed pre-existing POAG

Steroid-induced glaucoma

Epithelial ingrowth

Aphakic malignant glaucoma

DISEASES OF THE EYELIDS

A CASE OF BLEPHARITIS

CASE DESCRIPTION

Age and sex. Though more common in children, blepharitis may occur at any age equally in both sexes. Presenting symptoms. Patients usually complain of deposits at the lid margin, associated with irritation, discomfort, occasional watering and history of falling of cilia or gluing of cilia.

Ocular examination may reveal signs of either seborrhoeic or ulcerative (Fig.14.8) or mixed blepharitis.

Signs of seborrhoeic blepharitis are: accummulation of white dandruff-like scales on the lid margin. On removing these scales underlying surface is found to be hyperaemic (no ulcers). Lashes fall out easily. In long standing cases lid margin is thickened and the sharp posterior lid border tends to be rounded leading to epiphora.

Signs of ulcerative blepharitis. Yellow crusts are seen at the root of cilia which glue them together. Small ulcers, which bleed easily, are seen on removing the crusts. In between the crusts, the anterior lid margin may show dilated blood vessels (rosettes).

RELATED QUESTIONS

What is blepharitis and how do you classify it?

Blepharitis is a chronic inflammation of the lid margins. It can be divided into four classical types:

1.Seborrhoeic or squamous blepharitis

2.Ulcerative blepharitis

3.Mixed ulcerative with seborrhoeic blepharitis

4.Posterior blepharitis or meibomitis.

How will you differentiate squamous blepharitis from ulcerative blepharitis?

1.In squamous blepharitis white dandruff-like scales are seen at the lid margin while in ulcerative blepharitis yellow crusts are seen.

2.On removing the white scales underlying surface is found to be hyperaemic in sqamous blepharitis. While in ulcerative blepharitis, small ulcers which bleed easily are seen on removing the crusts.

3.Cilia may be glued together in ulcerative blepharitis, but not so in squamous belpharitis.

What are the complications of ulcerative blepharitis?

When not treated for a long time, the following complications may occur:

1.Chronic conjunctivitis

2.Trichiasis

3.Madarosis (sparseness or absence of lashes)

4.Poliosis (greying of cilia)

5.Tylosis (thickening of lid margin)

6.Eversion of punctum leading to epiphora

7.Recurrent styes

How will you treat a case of squamous blepharitis?

1.Scales should be removed from the lid margin with the help of lukewarm solution of 3 per cent soda-bicarb or some baby shampoo.

2.Combined steroid and broad spectrum eye ointment should be rubbed at the lid margin twice daily.

3.Associated seborrhoea should be treated adequately.

How will you treat a case of ulcerative blepharitis?

1.Hot compresses.

2.Crusts should be removed after softening with 3 percent soda bicarb.

3.Antibiotic ointment should be applied at lid margin immediately after removal of crusts.

4.Antibiotic eye drops should be instilled 3 to 4 times a day.

5.Oral antibiotics such as amoxycillin, cloxacillin, erythromycin or tetracycline may be useful.

A CASE OF CHALAZION (MEIBOMIAN CYST)

CASE DESCRIPTION

Presenting symptoms. Patient usually presents with a painless swelling near the lid margin. Patient may be concerned about the cosmetic disfigurement caused and may also feel mild heaviness in the lids. Sometimes, mild defective vision may occur due to astigmatism caused by pressure of chalarzion on the cornea.

Ocular examinations reveal a small, firm to hard, nontender swelling present slightly away from the lid margin (Fig.14.12). Overlying skin is normal and mobile. The swelling usually points on the conjunctival side as red, purple or grey area seen on everting the lid. Sometimes, the main bulk of swelling may project on the skin side and occasionaly on the lid margin.

Differential diagnosis. Chalazion needs to be differentiated from meibomian gland carcinoma, tuberculomata and tarsitis.

A CASE OF STYE

Presenting symptoms include acute pain and swelling in the lid. Patient also experiences heaviness in the eyelid, mild photophobia and watering.

Ocular examination during stage of cellulitis reveals tender swelling, redness and oedema of the affected lid margins (Fig.14.11). During stage of abscess formation a visible plus point on the lid margin in relation to the roof of affected cilia is formed.

Differential diagnosis. Stye (hordeolum externum should be differentiated from hordeolum internum.

RELATED QUESTIONS

What is a chalazion ?

Chalazion is also known as tarsal or meibomian cyst. It is a chronic non-infective granulomatous inflammation of the meibomian gland.

What is hordeolum externum (stye) ?

Hordeolum externum is an acute suppurative inflammation of one of the Zeis’ glands.

It is characterized by a localized, hard, red, tender swelling at the lid margin (PI.IV.I). In advanced stage, a pus point is visible at the lid margin.

What is hordeolum internum? How will you differentiate it from hordeolum externum?

Hordeolum internum is a suppurative inflammation of the meibomian gland associated with blockage of the duct. It may occur as primary staphylococcal infection of the meibomian gland or due to secondary infection in a chalazion (infected chalazion).

Its symptoms are similar to hordeolum externum except that pain is more intense due to the swelling being deeply embedded in the dense fibrous tissue. On examination it can be differentiated from hordeolum externum by the facts that in it, the point of maximum tenderness and swelling is away from the lid margin and that pus usually points on the tarsal conjunctiva (seen as a yellowish area on everting the lid) and not on the root of cilia.

When not treated, what complications can occur in a case of chalazion ?

1.A large chalazion of the upper lid may press on the cornea and may cause blurred vision due to induced astigmatism.

2.A large chalazion of the lower lid may rarely cause eversion of the punctum or even ectropion and epiphora.

3.Occasionally, a chalazion may burst on the conjunctival side forming a fungating mass of granulation tissue.

4.Due to secondary infection the chalazion may be converted into hordeolum internum.

5.Calcification may occur, though very rarely.

6.Malignant change into meibomian gland carcinoma may be seen occasionally in elderly people.

How do you treat a case of chalazion?

1.Conservative treatment in the form of hot fomentation, topical antibiotic eyedrops and oral anti-inflammatory drugs may lead to self-resolution in a small, soft and recent chalazion.

2.Intralesional injection of long acting steroid (triamcinolone) is reported to cause resolution in about 50 per cent cases.

3.Incision and curettage is the conventional and effective treatment for chalazion.

Describe the steps of incision and curettage of a chalazion.

1.Local anaesthesia is obtained by topical instillation of 4 percent Xylocaine drops in the conjunctival sac and infiltration of the lid in the region of chalazion with 2 per cent Xylocaine.

2.A chalazion clamp is applied with its fenestrated side on the conjunctival side and the lid is everted.

3.A vertical incision is made to avoid injury to the other meibomian glands.

4.The contents are curetted out with the help of a chalazion scoop.

5.To avoid recurrence its cavity should be cauterized with carbolic acid.

6.An antibiotic eye ointment is instilled and eye is padded.

What is the treatment of a marginal chalazion?

Destruction by diathermy is the treatment of choice for a marginal chalazion.

A CASE OF TRICHIASIS AND ENTROPION

DESCRIPTION OF A CASE OF TRICHIASIS

Presenting symptoms. Patients may present with a foreign body sensation, photophobia, irritation and lacrimation. Sometimes patient may experience troublesome pain.

Past history of the disease causative of trichiasis such as cicatrizing trachoma, ulcerative blepharitis, membranous conjunctivitis, mechanical injuries, burns and operation of the lid margin may be explored.

Ocular examination reveals one or more misdirected cilia touching the eyeball (Fig.14.16). There may or may not be signs of the causative disease.

DESCRIPTION OF A CASE OF ENTROPION

Presenting symptoms and past history exploration are similar to a case of trichiasis.

Ocular examination reveals inturned lid margin (Fig.14.17). Depending upon the degree of inturning the entropion can be divided into three grades. In grade I entropion, only the posterior lid border is inrolled. Grade II entropion includes inturning up to the intermarginal strip, while in grade III, the whole lid margin including the anterior lid border is inturned.

Examination may also reveal signs of the causative disease.

RELATED QUESTIONS

Define trichiasis.

Trichiasis refers to inward misdirection of cilia which rub against the eyeball.

What are the common causes of trichiasis?

1.Cicatrizing trachoma

2.Ulcerative blepharitis

3.Healed membranous conjunctivitis

4.Healed hordeolum externum

5.Mechanical injuries

6.Burns and operative scars on the lid margin

When not treated in time, what complications can occur in a case of trichiasis?

1.Corneal abrasions

2.Superficial corneal opacities

3.Corneal vascularization

4.Non-healing corneal ulceration

What is distichiasis?

Distichiasis is condition of an extra posterior row of cilia which occupy the position of meibomian glands.

How will you treat a case of trichiasis?

1.Epilation: It is a temporary measure.

2.Electrolysis: After local infiltration anaesthesia, a current of 2 milliampere is passed for about 10 seconds through a fine needle inserted into the lash root. The loosened cilia with destroyed follicles are then removed with the help of an epilation forceps.

3.Cryoepilation: After infiltration anaesthesia, the cryoprobe (–20°C) is applied for 20 to 25 seconds to the external lid margin. The loosened lash is pulled with an epilation forceps.

4.Surgical correction: It is similar to cicatricial entropion and should be employed when many cilia are misdirected.

Define entropion.

Entropion refers to turning in of the lid margin.

What are the types of entropion?

Depending upon the cause,entropion may be of the following types:

1.Congenital entropion

2.Cicatricial entropion

3.Spastic entropion

4.Mechanical entropion

What are the causes of cicatricial entropion?

1.Trachoma

2.Membranous conjunctivitis

3.Chemical burns

4.Pemphigus

5.Stevens-Johnson syndrome

Name the surgical techniques employed for correcting cicatricial entropion.

1.Resection of skin and muscle

2.Resection of skin, muscle and tarsus

3.Modified Burow’s operation

4.Jaesche-Arlt’s operation

5.Modified Ketssey’s operation

Name the surgical techniques used to correct a senile (involutional) entropion.

1.Modified Wheeler’s operation

2.Bick’s procedure with Reeh’s modification

3.Weiss operation

4.Tucking of inferior lid retractors (Jones, Reeh and Webing operation).

A CASE OF ECTROPION

CASE DESCRIPTION

Presenting symptoms include watering (epiphora) and cosmetic disfigurement. Patients may also have symptoms of associated chronic conjunctivitis which include irritation, discomfort and mild photophobia. Ocular examination. The lid margin is outrolled (Fig. 14.24). Depending upon the degree of outrolling, ectropion can be divided into three grades. In grade I ectropion, only the punctum is everted. In grade II ectropion lid margin is everted and palpebral conjunctiva is visible while in grade III the fornix is also visible.

Examination may also reveal signs of aetiological condition such as scar in cicatricial ectropion (Fig. 14.25) and seventh nerve palsy in paralytic ectropion.

RELATED QUESTIONS

What is ectropion ?

Outrolling or outward turning of the lid margin is called ectropion.

What are the types of ectropion?

1.Senile ectropion

2.Paralytic ectropion

3.Cicatricial ectropion

4.Spastic ectropion

What is the treatment of senile ectropion?

Depending upon the severity of the ectropion, following three operations are commonly performed:

1.Medial conjunctivoplasty

2.Horizontal shortening

3.Byron-Smith’s modified Kuhnt-Szymanowski operation.

What is a symblepharon?

Symblepharon is a condition in which lids become adherent with the eyeball. It results from healing of the kissing raw surfaces of the palpebral and bulbar conjunctiva.

What are the common causes of symblepharon?

1.Chemical burns

2.Thermal burns

3.Membranous conjunctivis

4.Conjunctival injuries

5.Ocular pemphigus

6.Stevens-Johnson syndrome

What do you mean by ankyloblepharon?

Ankyloblepharon refers to the adhesions between margins of the upper and lower lids. It may be congenital or may result after healing of chemical or thermal burns.

What is blepharophimosis?

In blepharophimosis vertical as well as horizontal extent of the palpebral fissure is decreased.

What is lagophthalmos? Enumerate its common causes.

Lagophthalmos refers to the inability to voluntarily close the eyelids. Its common causes are:

1.Paralysis of seventh nerve

2.Marked proptosis

3.Cicatricial contraction of the lids

4.Following over-resection of the levator palpebrae superioris

5.Symblepharon

6.Comatosed patient

What is belpharospasm ?

Belpharospasm refers to the involuntary, sustained and forceful closure of the eyelids. It is of two types: essential belpharospasm and reflex blepharospasm.