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Home , Exposure keratopathy

1- The Lacrimal System Anatomy enlightenments :

Lower lacrimal punctum is 0.5mm lateral (LL rule)

Complex apparatus which has 8 valves

Common canaliculus exist in about 90% of individuals in the remaining 10%, the upper and lower canaliculi enter the lacrimal sac separately.

Lower orifice of the nasolacrimal canal opens in the inferior meatus of the nose

Negative drainage (Gravity) and positive drainage (Lacrimal pump)

Nasolacrimal duct obstruction :

In newborns usually caused by persistence of a membrane at the level valve of Hasner

In adults concerning to AAO the most cause is the nasolacrimal stenonsis.

Other factors causing lacrimal obstruction include :

•Age-related changes (puncta get narrower). •Infection or inflammation. •Injury or trauma. •Tumor. •Long-term use of eyedrops. (antiglaucoma,antiviral) •Cancer treatments. Classification of Tests for lacrimal drainage pathway:

Anatomical tests: locate the probable area of lacrimal tract obstruction •Palpation of lacrimal sac •Syringing / irrigation •Diagnostic probing •Dacryocystography Nasal examination •CT / MRI

Functional tests:access the function of under physiologic conditions. •Flourescein dye disappearance test •Scintigraphy •Jones dye test I

Secretory tests: secretory function of the lacrimal apparatus (dry eye). •Schrimers test •Bengal Rose test •Tear-film break up •Tear lysozyme But before all tests, the most important are:

the history & careful examination.

So you can differentiate between :

Epiphora is watering that occurs secondary to abnormal excretory system in the presence of normal tear secretion.

Lacrimation, is watering that occurs secondary to excessive tear production in the presence of a normal excretory system. Physical examination: Symptoms:

❖Visual acuity, best corrected ❖Tearing () ❖Assessment of pupillary function and ocular motility ❖Mucopurulent discharge ❖Slit-lamp biomicroscopy of the anterior segment ❖Mattering of lashes and lids, crusting in the ❖Assessment of tear meniscus height (normal morning 0.2mm) , and quality ❖Pain ❖Lower tone (e.g. measurement of ❖Blurred vision from distraction/laxity, snapback test) ❖Bloody tears ❖Eyelid position (e.g. apposition, retraction, ❖ (abscess infection of the , , ) lacrimal sac in the inner corner of eye area) ❖Nasal evaluation (e.g. nasal vestibule, deviated septum, polyposis, intranasal tumors, allergic rhinitis, turbinate impaction) ❖Punctal patency and position ❖Dye disappearance test to demonstrate delayed clearance of ❖Probing and irrigation of nasolacrimal system Updates & basic info.

Congenital Nasolacrimal Duct Obstruction (CNLDO):

Is a common condition for epiphoria (affects 20% children < 1 year worldwide) often resolved without surgery treatment options :

•Observation (best option in children < 1 year resolving in 95% by the age of 13 months ) •Lacrimal sac massage + antibiotics •NLD probing ( children > 1 year best age 4-6 months) •Repeat probing ( after 1 month from primary probe in ages 6-48 months untill 3 years it still effective) •Silicone tube intubation ( after failed 2ed probing, left from 2-6 months longer is best, 65% success rate) •Balloon catheter dilation ( more cost, complex cases ) •DCR ( paediatric DCR indicated when is no response to previous therapy, from age of 3 years, classic DCR 60% minor so endoscopic is safer)

New studies shows that NLD silicon intubation with endoscopic visualization has favourable outcomes in primary CNLDO in children 7 years and older and reduces the need for DCR which is more invasive procedure.

For CNLDO Probing :

•Bowman probe size ranging from 000 to 1 •Perform probing under GA to reduse the risk of truma and make it easier to the child and the parents •in case of problems use endoscopic smart lacrimal probes

Instruments: •Castroviejo Lacrimal Dilator •Bowman probes( or Miyake) length 13 cm ✓size (0000-000\ 0.6-0.7mm) ✓size (00-0\ 0.8-0.9mm) ✓size (1-2\ 1.0-1.1mm) ✓size (3-4\ 1.2-1.3mm) ✓size (5-6\ 1.4-1.5mm) ✓size (7-8\ 1.6-1.7mm) Intubation instruments: •Crawford Lacrimal Intubation Set (0.4mm probe diameter, olive tip 1mm diameter, silicone tube 0.64mm -0.93mm diameter with 0.30mm lumen) •Retrieval Device (Crawford Hook, grooved director) •Lacrimal Trephine (Sisler )80 X 38 mm 21 G (canalicular atresia) Lacrimal Trephine [Sisler] micro trephine useful for rotary trepanation of an obstructed canaliculus & biopsy of the or . Masterka tube:

Latest FCI innovation for treatment congenital NLD obstruction resistant to probing. It's not pulled out the nose but anchored in place at punctum buy a plug like head, easy to insert. No retrieval no knock or sutures less trauma.

Endoscopic probing for complex cases : Dacroplasty & DCR using balloon : DCR (Dacryocystorhinostomy) : in all of its types ( classical, PAWAR, endoscopic, laser) is an anastamosis between the lacrimal sac and the middle meatus of nasal cavity to bypass the nasolacrimal duct obstruction.

The most recent DCR technique Transcanicular laser assisted DCR (TLDCR)

Advantages over external DCR : minimal trauma preserve medial canthal anatomy lower morbidity

Holmium:Yttrium-Aluminum-Garnet (Ho:YAG) laser

Laser canalicular plastic surgery using the erbium-YAG laser

Not indicated in inflammations & neoplasia.

CDCR: 2-Evaluation of proptosis

Bacsic Terms: ❖ term is reserved for those cases of proptosis secondary to endocrinological(thyroid) dysfunction. ❖Proptosis: Signifies protrusion of eyeball due to all other causes. ❖Dystopia: Displacement of globe in coronal plane. It may coexist with proptosis or ❖Exorbitism: This is caused due to decrease in the volume of causing the orbital contents to protrude forwards. Should be differentiated from proptosis/exophthalmos. ❖Pseudoproptosis needs to be ruled out as false impression of proptosis which may be given by: -High ( unilateral enlargement of globe) -Unilateral lid retraction. -Enophthalmos of C/L eye -Paralysis of extrinsic muscles. Algorithm for approach to a case of proptosis:

❑History

❑Ocular & systemic examination

❑Specific examination of proptosis

❑Provisional diagnosis

❑Imaging

❑Revision of provisional diagnosis( if required)

❑Investigations Confirmation by histopathological

❑examination Management plan( according to final diagnosis)

❑ Monitoring course of disease A) HISTORY:

A complete history should be recorded. Evaluation of the patient with exophthalmos begins with a thorough ophthalmic and medical history. When concomitant sinus disease or an intranasal source is suspected, a speculum or endoscopic intranasal examination is warranted Time course of disease: acute( hours-days), subacute(weeks), chronic(months/years)

ACUTE: -traumatic: e.g orbital hematoma -infective: e.g SUBACUTE: -inflammatory: e.g orbital inflammatory diseases, thyroid orbitopathy. -neoplastic. CHRONIC: -neoplastic, benign/malignant -inflammatory.

Progression: The proptosis my be progressive,static or waxing- waning. Rare cases of intermittent proptosis are caused by dumb-bell dermoids,with components in the orbit & the temporal fossa. Medical & systemic history: pt asked for h/o malignancy,weight loss,smoking. Biological effects of disease: pain, swelling around the eye,diminished vision,watering, . B) OCULAR EXAMINATION:

Visual acuity: diminution d/t compression, corneal exposure. Refraction: acquired hyperopia d/t mass indenting the posterior pole of globe, high myopia causing pseudoproptosis. IOP: thyroid orbitopathy( d/t restriction of movt.), aretriovenous fistula (d/t elevated venous pressure) Conjunctiva: chemosis (in severe inflammation), salmon colored patch (in lymphoma), dilated episcleral vessels (carotid cavernous fistula) : lid retraction,lid lag in thyroid orbitopathy, S-shaped lid thickening (neurofibromatosis), : . : lisch nodules. (neurofibromatosis). : RAPD Ocular motility limitations: direct muscle involvement by disease, mechanical limitation,compression of nerves, cavernous sinus thrombosis. Fundus examination: edema, disc pallor, choroidal/ ILM folds. MEASUREMENTS:

Asymmetry > 2mm or more b/w the eyes.

OR Protrusion greater than :

-13-15mm in east asians -21mm in caucasian adults. -23mm in adult african-americans

In children and teenagers mean exophthalmometric measurements increase with age: Less than 4 years old (13.2 mm), 5–8 years old (14.4 mm), 9–12 years old (15.2 mm) and 13–17 years old (16.2 mm). Depending upon the configuration of the osseous orbit, a value of 15mm might be pathological whereas 21mm might be normal. Clinical methods for measurement of proptosis:

A) PLASTIC RULER: can measure proptosis from the lateral orbital rim to the corneal apex,holding the ruler parallel to ground.

B)LUEDDE’S EXOPHTHALMOMETER: has several advantages -notch confirms to lateral orbital rim. -the scale starts from tip of instrument,where the notch meets the lateral orbital rim. -markings on both sides help to avoid parallax error. -luedde’s exophthalmometer is better than hertel’s if there is facial asymmetry.

C) HERTEL’S EXOPHTHALMOMETER: m/c used. -it may use prisms or mirrors set at 45 degree angles. -it is best for serial follow up of patients.

D) NAUGLE’S EXOPHTHALMOMTER: -In case of acquired or congenital asymmetry of the lateral orbital rims a Hertel exophthalmometer is misleading -This is an inferior & superior rim based instrument. -may be used when the lateral orbital rim is not intact.

E) Gormaz Exophthalmometer : mechanical -Measure distance between two lateral orbital margins - Require topical anaesthesia

The basis of the measurement for exophthalmos determination using the Hertel version is the outer orbital rim (orbital wall) and the apex of the cornea. The internal refraction mirrors with millimeter scales for the left-hand and right-hand measuring halves of the exophthalmometer are calibrated so that the zero mark on the scale will be located in the plane of the resting points of the supports. For exophthalmus measurements the supports are placed against the two temporal orbital walls so that the orbital rim contacts the deepest point of the supports. Prisms are clear plastic with easy to read millimeter lines on both sides. Eye is seen through lower half of scale and the scale is seen through the upper half, eliminating parallax and aiding rapid determination of protrusion. The examiner sits opposite the patient at eye level. The exophthalmometer is then positioned with the index points at the temporal lateral orbital walls. The instrument hold with both hands and firmly propped first against the patient’s right orbital wall on the temporal side(which should be felt against the lowest part of the support point). The moveable part on the right side is then set in such as way that the patient’s left orbital wall lies against the lowest part of the arched support. The distance between the lateral orbits (on scale 2) should be noted for future correlation.The examiner asks the patient to look at right ahead with eyelids wide open. The examiner measures for proptosis in each eye.

SOURCES OF ERROR IN EXOPHTHALMOMETRY:

A)failure to have pt look straight.

B)failure to have cross bar parallel to floor.

C)parallax error.

MEASURING PROPTOSIS ON A CT SCAN HILAL AND TROKEL METHOD:

-In a mid axial CT scan image,a baseline between the tips of lateral orbital rims is drawn.

-a perpendicular from each corneal apex to this line is dropped & measured to scale. Quick clinical assessment of proptosis:

Worm’s eye view: looking up at pt from below,while pt tilts his head back. 3-Evaluation of

PTOSIS:ABNORMALLY LOW POSITION OF UL IN PRIMARY GAZE IN NORMAL GAZE IT COVERS 1/6TH OF THE CORNEA(2 MM) IN PTOSIS IT COVERS MORE THAN THAT.

The word “PTOSIS “ DERIVED FROM: GREEK LANG, MEANS : TO FALL

BEFORE ANY JUDGEMENT WE NEED TO DIFFERENTIATE BETWEEN : PSEUDOPTOSIS &TRUEPTOSIS PSEUDOPTOSIS : IT IS TO BE RULED OUT ON INSPECTION

❖IPSILATERAL : ▪MICROPHTHALMOS ▪PTHISIS BULBI ▪ENOPHTHALMOS ▪PROSTHESIS ▪DERMATOCHALASIS

❖CONTRALATERAL : ▪EYELID RETRACTION ▪HIGH MYOPIA ▪PROPTOSIS

GRADING:

MILD PTOSIS: 2MM MODERATE PTOSIS: 3 MM SEVERE PTOSIS : 4 MM

EVALUATION :

HISTORY: A PREVIOUS PHOTOGRAPH CAN HELP DISTINGUISH THE AGE OF PTOSIS AS THE PATIENT MAY BE GIVING IRRELEVANT HISTORY. Measurments:

MARGIN-REFLEX DISTANCE: DISTANCE BETWEEN THE UPPER LID MARGIN AND THE CORNEAL REFLECTION OF A PEN TORCH HELD BY US AT WHICH THE PATIENT IS DIRECTLY LOOKING. NORMAL IS 4-4.5 MM PALPEBERAL FISSURE HEIGHT: DIST BETWEEN THE UL AND LL MARGINS THE UL MARGIN 2MM BELOW THE UPPER LIMBUS AND THE LL MARGIN 1MM ABOVE THE LOWER LIMBUS IN MALES: 7- 10 MM IN FEMALES: 8-12 MM CAN BE CLASSIFIED AS MILD MODERATE SEVERE UPPER LID CREASE: IT IS VERTICAL DISTANCE BETWEEN THE LID MARGIN AND THE LID CREASE IN DOWNGAZE

FEMALES:10 MM MALES: 8 MM

LEVATOR FUNCTION:PLACE A THUMB FIRMLY OVER PATIENTS BROW TO NEGATE THE ACTION OF FRONTALIS MUSCLE WITH THE EYES IN DOWNGAZE THEN THE PATIENT IS ASKED TO LOOK UP AS FAR AS POSSIBLE THEN THE EXCURSION IS MEASURED BY A RULER. ASSOCIATED SIGNS:

FATIGABILITY: ASK THE PAT. TO LOOK UP WITHOUT BLINKING FOR 30 SECONDS IF THE PATIENTS FAILS TO MAINTAIN THE UPWARD GAZE IS SUGGESTIVE OF M.G

COGAN TWITCH SIGN: OVERSHOOT OF THE UL ON SACCADE FROM DOWNGAZE TO THE PRIMARY POSITION. Specificity of the CLT to be 99%, with a sensitivity 75% and false-positive rate 1%. The CLT test is a specific and sensitive test to use in a neuro- clinic to evaluate for MG.

JAW WINKING PHENOMENON:CAN BE SEEN IF THE PATIENT IS PTOTIC AND WE ASK THE PATIENT TO CHEW OR OPEN HIS/HER MOUTH.

BELLS PHENOMENON: IT IS TESTED BY MANUALLY HOLDING THE LIDS OPEN,ASKING THE PATIENT TO TRY TO SHUT HIS EYES AND OBSERVING THE UPWARD AND OUTWARD ROTATION OF THE GLOBE OTHER TESTS

Ice Pack Test : THIS TEST IS AN EASY PROCEDURE ASK THE PATIENT TO SIT COMFORTABLY ASK HIM/HER TO CLOSE THEIR EYES HOLD AN ICE PACK OVER THE CLOSED EYES WAIT FOR 5 MINUTES OBSERVE AFTER 5 MINUTES NOTE ANY IMPROVEMENTS EDROPHONIUM(TENSILON)TEST:

EDROPHONIUM CHLORIDE INHIBITS ACETYLCHOLINESTERASE IT RESULTS IN THE PROLONGED PRESENCE OF ACT A THE NMJ THIS RESULTS IN ENHANCED MUSCLE STRENGTH POSITIVE: ELEVATION OF EYELIDS IN 2-5MINS POST ADMINISTRATION OF TENSILON NEGATIVE: NO IMPROVEMENT EVEN 3 MINUTES DRAWBACK: THIS HAS A RELATIVELY LOW SENSITIVITY APPROX. 60% FOR MG S/E: DUE TO OVERACTIVATION OF THE PARASYMPATHETIC SYSTEM & CAUSE UNWANTED S/E FAINTING,DIZZINESS,INVOLUNTARY DEFECATION, SEVERE BRADYCARDIA,APNEA, AND THE MOST DREADED ONE CARDIAC ARREST. SAVIOR: ATROPINE AT HAND