Differentials of Unilateral Central Scotoma

Hey, guys this post will be on the differential diagnosis of "Blurred Vision in one eye" due to a central scotoma.

So a central scotoma can be usually due to retrobulbar neuritis(inflammation of the optic nerve) or optic nerve compression.

Now when you have detected a central scotomata in one eye it is essential to do the confrontation test in the other eye also. If in the other eye you detect a defect in upper temporal field, a superior temporal quandrantonopia; it is higly likely that this is a case of optic nerve compression.

How so? Well refer the attached pic with the illustrated diagram and I am sure you will understand. :)

-VM

Studying made simple: Ocular signs of thyrotoxicosis

Hey Awesomites

I read about ocular signs seen in patients with thyrotoxicosis. On googling and partly my work, studying these signs has become so simple to remember. -

Brainstem Syndromes!

So let's get done with all the important brainstem syndromes once and for all !

I would be writing on all of them one by one...

Also ...I will try and incorporate many of my diagrams to help you guys make it seem less daunting...

Starting from the Midbrain the first syndrome is..

(The image shows the level of the lesion)

1):Parinaud's Syndrome

Lesion location:Midbrain dorsum ,superior  collicculi.

Structures involved: Quadrigeminal plate region; pretectum; periaqueductal gray matter

Etiology: •Due to mass lesion in the region of the posterior third ventricle, most often pinealoma, or due to midbrain infarction.

Clinical features:
•Impaired upgaze as centre for upward gaze is affected
convergence retraction nystagmus;
Argyll Robertson pupil :dilated pupils with light near dissociation.

A closer look at the structures involved .

I hope it helped !Also do share your Neuroanatomy diagrams and and more information on Parinaud Syndrome.

Have a nice day!

-Medha!

Grave's ophthalmopathy features mnemonic

Hey Awesomites

Grave's disease, a common cause of primary hyperthyroidism causes some epic features of ophthalmopathy apart from lid retraction and lid lag. Mnemonic: EPIC

E- Exophthalmos
P- Periorbital Edema
I- Involvement of ocular muscles (diplopia)
C- Conjunctival irritation and chemosis

- Jaskunwar Singh

Stigmata of Hypercholesterolemia

Hello

There are certain physical stigmata of hypercholesterolemia that help the clinician to suspect FH in a patient with a premature cardiovascular disease:

- Xanthelasma (cholesterol deposits on both eyelids)
- Arcus corneae (bilateral; detected by fifth decade of life)
- Tendinous xanthomas (in hand and feet)


That's all
- Jaskunwar Singh

Steroids and the Eye : Utility Review

Hello everyone ! I'm back with another post on Opthalmology ! Hope you like it.

∆ Uses of Steroids in Ophthalmology -

1. Prophylactic - PC
- Post op Cataract - 6w
- Corneal grafting.

2. Therapeutic - Go from anterior to posterior. We use it in every layer of the eye !

- Lids - Intralesional for Chalazion

- Conjunctiva - Phlyctenular Conjunctivitis.

- Sclera and Episcleral tissue - Scleritis and Episcleritis.

- Cornea - Contra indicated - As it affects healing and may cause super infections.

- Uvea - Anterior and Posterior Uveitis. Purulent Uveitis - Endophthalmitis ; Panopthalmitis.

- Retina - Diabetic Retinopathy Intravitreal Triamcinolone.

- Nerve - Optic Neuritis ( Multiple Sclerosis ) - Methyl Prednisolone

3. Others :
- Secondary Glaucoma due to the Inflammatory etiology.

~~~~~~~~~

∆ Precautions :

- Avoid in any ulcer cases as it can delay healing of the ulcer or aggravate fungal or herpetic ones.

- Can cause Cataract - Posterior Subcapsular. (Generally when given systemically)

- Can cause Glaucoma ( Generally when used Topically. )

Hope you liked it !
Stay awesome !

Occupation and Ophthalmology : Clinical Pearl

Hello everyone.
I'm back with another ophthalmology post. This one is more of a clinical post , something that would be important to you in any specialty! Hope you like it. :)

So our life is all about being a successful doctor at the moment. Cause we wanna be good at our jobs !
Everyone wants to succeed at the work place. But there are loads of occupational hazards or diseases that we end up acquiring or aggravating due to the kind of job we do.

In this post I'll be talking to you about what ocular diseases can occur in Association with certain occupations.

1. Pterygium
- Occur commonly in farmers, driving school teachers and construction workers.
- Due to  exposure to sunlight for a long duration of time.

2. Fungal corneal ulcer or other fungal infections of the eye
- can occur commonly in farmers again. Because they are at a higher risk of vegetative trauma

3. Computer vision syndrome :
- seen in people working with electronic devices on an extensive level.
- the complains include dry eye , headache , eye strain , neck and shoulder aches.
- Simple tip for prevention - called the 20 20 20 rule.
Every 20 minutes look away from the screen for at least 20 seconds at an object about 20 feet away.
- Frequent blinking.
- Use of Lubricant for the eye.
- Use of anti glare screen/ spectacles.

4. Miner's nystagmus :
- seen in coal workers.
- Photophobia and night blindness may accompany the Nystagmus.

5. Glass blower's cataract :
- Occurs in glass makers.
- infrared rays cause damage to the lens producing this kind of cataract.

6. Welder's flash :
- seen in welders.
- It's a form of Photokeratitis
- Occurs due to UV rays
- causes abrasion , conjunctivitis and eye strain.

That's all for today !
Hope this helped.
Stay awesome !

~A.P.Burkholderia

Tuberculosis : Ocular Manifestations

Hello everyone !
This is a short post about the manifestations of Tuberculosis in the eye.

TB is associated with a lot of findings in the eye.
We can classify them as :
1. Disease related.
2. Therapy related.

Let's look at the first one.

1. Disease related :

A. Extra Ocular structures -

    I. Appendages :
       Eyelid - Lupus Vulgaris. Lid granuloma.
       Lacrimal apparatus - TB Dacryoadenitis. Dacryocystitis.
      
    II. Orbit :
         Orbital Cellulitis.
         Orbital Pseudotumor.

B. Ocular manifestations -
    
     I. Conjunctiva -
         Phlyctenular Conjunctivitis - due to hypersensitivity to Tuberculin. Seen as intense itching , discharge , redness and nodules.

     II. Cornea -
          Interstitial Keratitis

     III. Uvea -
          Granulomatous uveitis ( Chronic anterior Uveitis ). Shows Mutton Fat appearance.

          Choroiditis - Choroid Tubercles - classic of TB Uveitis. Tuberculoma may be seen. Miliary choroid nodules may be seen.

      IV. Retina -
            Eale's disease - may be a result of Hypersensitivity to Tuberculin. Although causality is not established clearly.
           Sub retinal Tubercles.

2. Therapy Related :

       A. Ethambutol - may cause Optic Neuritis - generally retrobulbar type. With Color Blindness.

      B. INH - Isoniazid can cause retrobulbar optic neuritis, although this is much rarer.

     C. Immune Reconstitution Inflammatory Syndrome - When a person recuperates from TB /HIV his immune system may become hyperactive and show Immunologically mediated uveitis.

Hope this helps !
Happy studying.
Stay awesome. 

~A.P.Burkholderia

Nodule at the Limbus : Mnemonic

Hello everyone !
Here's a way to remember the D/D's of Nodules at the Limbus.

Mnemonic :
Please Please Please ! Eat Spicy MCDonald's Tortilla.

Please - Pterygium.
Please - Pinguecula.
Please - Phlycten.
Eat - Episcleritis.
Spicy - Scleritis.
M - Melanoma. 
C -  Choristoma
Donald - Dermoid.
Tortilla - Trachoma. Tranta spots.

1. Out of these Pterygium , Pinguecula and Phlyctens are Conjunctival lesions.
Pterygium is a fold of conjunctiva that encroaches towards the pupil.
It can be vascular and nodule like. Can cause Foreign body sensation and decreased vision if it covers the pupil.
It may also cause Diplopia and a Squint due to its traction over the eye.
A pinguecula is milky like nodular swelling of the conjunctiva.
A Phlycten is a lesion in Phlyctenular Conjunctivitis which is an allergic or Hypersensitivity response to Tuberculin or staph Antigens. There is intense itching , discharge and nodules in the eye - called Phlyctens.

2. The lesions of Episcleritis and Scleritis are similar. They're both associated with systemic disease like Rheumatoid Arthritis , SLE, Sarcoidosis etc.
Scleritis is a more severe one of the two. There's marked redness and congestion of the eye along with multiple vascular nodules. The eye is very inflamed. There is intense pain and watering. It needs urgent treatment. It may causes various types of staphylomas.
Episcleritis is a more benign form. There is intense itching , nodular vascularity and discharge with some amount of congestion.

3. Tumors like Choristoma , Dermoid tumor and Melanoma mainly arise from the uvea. They're not very common.

4. Trachoma : presence of lesions in trachoma at the nodule may be prominent. You may also get 'Horner Tranta spots' in Vernal Keratoconjunctivitis which is an allergic Conjunctivitis.

Hope this helped !
Stay awesome !
Happy Studying!

How to check for the Pupils : Clinical Pearl

Hello everyone !
This is a post about how to look for a normal pupil while doing an ophthalmological examination.
So here goes :

1. The Setting.
- Relax the Patient
- Take the patient to a semi dark room.
- Make the patient Fixate on a distant point to eliminate any error that Accomodation may produce.
- Place an obstruction between the two eyes.
- Always shine your torch laterally and bring it in only from the sides to avoid light shining directly on the other eye.

2. The Parameters.
Look for the following in the pupils :
- Size
- Shape  ( for eg. You may get a Festooned pupil on adding your Mydriasis if the patient has adhesions)
- Number ( for eg. You may get Poly Coria which causes Diplopia )
- Location  ( for eg. You may get Corectopia)

3. Reaction to light.
- Unless you've met the criteria above ( The setting) , you cannot say 'Direct and indirect reflex present' .
So unless you're in a semi dark room (and the other 3 criteria mentioned above) you would plainly shine the torch and look for constriction. This plainly shows the pupils are reactive to light.

4. Light Reflexes.   
- Check for your direct and consentual (indirect) reflexes in both your eyes after meeting the listed Criteria in the *Setting* !

Hope this helps !
Happy studying !
Stay aweosme.

~A.P.Burkholderia

Argyll Robertson Pupil : Mnemonic

Hello everyone ! I'm back with a short and sweet post on Argyll Robertson Pupil.

Mnemonic for Argyll Robertson  Pupil (ARP) :
ARP Accomodation reflex present
PRA Pupillary reflex absent.

It's seen in conditions like Neurosyphilis for which it is extremely specific. 
You could also see it in some form of strokes or Diabetic Neuropathy.

Another similar Pupillary reaction is Aedes pupil. The difference is Aedes is a  dilated pupil while Argyll's is constricted. How to remember this ?
Mnemonic : AeDes.
So Aedes is tonically Dilated.

Hope this helped !
Stay aweosme.
Thanks.

Extra Ocular Muscles Insertion : Mnemonic

Hello everyone ! I hope you'll have been enjoying the Top 10 Series that we've started. This is a short post on the insertion of Extra ocular muscles in the eye.

So there are 4 Extra Ocular muscles whose insertion on the sclera we need to be aware of ( in terms of distance from the Limbus). The Recti.

Remember :
I'M Low Standard

I = Inferior Rectus. 5.5
M = Medial Rectus 6.6 (or 6.5 but just remember 6.6 for easiness)
L = Lateral Rectus  6.9 (Loser)
S = Superior Rectus 7.7

So basically it starts with 5.5 , 6.6, 6.9 and finally 7.7.
3 of these are the same number repeated (5.5 , 6.6 and 7.7) but LR is a loser. Hence it does not follow the rule and is a badass hence does a 69. :p

Hope this helped !
Thank you.
Happy studying!

~A.P.Burkholderia

Classification of closed globe injuries

Closed globe injury classification:-

- Based on the mechanism of injury (type) :
A. Contusion (blunt trauma)
B. Lamellar laceration (due to a sharp object or blunt trauma)
C. Superficial foreign body (organic matter or metals)
D. Mixed (combined injuries)

- Based on the visual acuity (grade) :
A. >20/40 (0.5)
B. 20/50 - 20/100 (0.4 - 0.2)
C. 19/100 - 5/200 (0.2 - 0.025)
D. 4/200 - Light Perception (0.02 - L+ P+ )
E. No Light perception

- Based on the pupillary defect :
A. Relative afferent pupillary defect (RAPD) positive
B. Relative afferent pupillary defect (RAPD) negative

- Based on the Zones of violations :
Zone I- External (superficial injuries of bulbar conjunctiva, cornea and sclera)
Zone II- violation of the Anterior segment (structures in anterior chamber and the pars plicata)
Zone III- violation of the Posterior segment (structures posterior to the posterior lens capsule- retina, vitreous and optic nerve)


Thats all
- Jaskunwar Singh

Ectopia lentis mnemonic

Ectopia lentis (or lens dislocation) associated conditions mnemonic.

- MarFAN syndrome (FAN is up)- Superior dislocation of the lens
- HomocystinURIA (URINE goes down)- Inferior dislocation
- WeilMARCHesani syndrome (We will march forwards)- Anterior dislocation of the lens


Thats all
- Jaskunwar Singh

Vogt's triad in congestive glaucoma mnemonic

Vogt's triad in acute congestive glaucoma:
GAP
G - Glaucomflecken
A - Atrophy of iris stroma
P - Pupil dilatation

Also, check out the Vogt's triad in tuberous sclerosis mnemonic here

- Jaskunwar Singh

Herpes Zoster Ophthalmicus notes

Herpes zoster ophthalmicus

This viral infection is associated with a previous childhood exposure to varicella zoster (chickenpox) which remains hidden within and becomes active later in life when immune functions of the body weaken.

Membranous and pseudo-membranous conjunctivitis notes

Pseudo-membranous conjunctivitis: mild form
Membranous conjunctivitis: severe form

Causative agents:
Corynebacterium diphtheriae
Beta- hemolytic streptococci
Streptococcus pneumoniae
Neisseria gonorrheae

Associated conditions:
Erythema multiforme
Stevens- Johnson syndrome

Pseudomembranous:
- Lid swelling
- mucopurulent bloody discharge
- white membrane
- easily peel off without bleeding

Membranous:
- Lids are hardened
- semisolid exudates: result in necrosis of conjunctiva and cornea
- difficult to peel off
- associated with bleeding from the undersurface

Important points to be noted:-
- The membrane forms more commonly over palpebral conjunctiva beginning from the edge of lid.
- There is enlarged preauricular lymph nodes with suppurative discharge.
- Marginal corneal ulcer due to secondary infection (especially streptococci).
- high risk of symblephron (adhesion between palpebral and bulbar conjunctiva)

Treatment:
- Penicillin (10,000 units/ ml) is the doc for acute diphtherial infection. Systemic administration and a quick injection of anti- diphtheritic serum (4,000- 10,000 units BD) 
- Removal of the membranes is not advised because of the risk of adhesion (symblephron).
- Local and systemic administration of bacitracin and penicillin is recommended in case of streptococcal infection.

Pseudotumor cerebri notes

Pseudotumor cerebri

Associated with:
Obesity
Vitamin A toxicity

Signs and symptoms:
Headache
Sixth nerve palsy
Visual field defects
Pulsutile tinnitus

Diagnosis:
Papilledema
To rule out space occupying lesions - CT / MRI normal
Most accurate - Lumbar puncture with opening CSF pressure measurement

Treatment:
Weight loss
Acetazolamide
Surgery

Why does increased ICP cause 6th nerve (Abducens) palsy?
Increased ICP can result in downward displacement of the brainstem, causing stretching of the sixth nerve secondary to its location within  Dorello's canal.

That's all!
-IkaN

Amaurosis fugax mnemonics

I was studying the causes of Amaurosis fugax today.. so i just made random mnemonics and thought of sharing with you guys :D

Amaurosis fugax is a transient uniocular loss of vision either due to lack of blood supply to the brain or to the retina itself.

Symptoms of corneal disorders mnemonic

I was studying corneal disorders and dystrophies, infections, inflammations today and noticed many common symptoms in the patients.

Now since its the matter of the eye, I must tell you how much I love photography and also i used to do some painting stuff long ago. So i made a random mnemonic out of it for the symptoms of corneal disorders.. :p

DSLR Photography and Painting Workshops.

D- Decreased vision

S- Sensations (foreign body)

L- Lacrimation

R- Redness

P- Photophobia

P- Pain

W- white cornea

Thats all

- Jaskunwar Singh