Wednesday, April 26, 2017
Tuesday, April 25, 2017
Deviated Nasal Septum - "Abnormal and asymmetrical alignment of the nasal septum that results in acute nasal obstruction and other symptoms of upper respiratory tract."
1. Trauma : Abnormal pressure ( lateral or frontal ) applied to nasal septum results in its deviation to one side or another.
- The lateral blow may cause displacement of septal cartilage from the vomerine groove and maxillary crest.
|Groove on which septal cartilage sits ( encircled ) - lateral view|
Diagram by IkaN.
- Frontal blow causes crushing injuries to the nose, usually occurs in sportspersons especially the boxers.
2. Developmental anomalies : Palate forms the base of nasal septum. Highly arched palate, cleft palate or lip, and dental abnormalities can all lead to deviation of the septum.
3. Racial factors : Caucasians have more incidence of DNS.
4. Hereditary : Familial predisposition.
TYPES of DNS -
1. Anterior dislocation : dislocation of nasal septum into one of the chambers. ( unilateral nasal obstruction )
2. C - shaped dislocation : simple curve to one side with compensatory hypertrophy of turbinates in other side. It causes unilateral nasal obstruction.
3. S - shaped deformity : causes bilateral nasal obstruction
4. Spurs : shelf - like projections may lead to headache and epistaxis. ( unilateral obstruction )
5. Thickening : due to septal hematoma
CLINICAL FEATURES of DNS mnemonic
TREATMENT - Only required if the symptoms are severe. The procedures are to be done once the patient is more than 17 years old.
- Septoplasty : The most deviated parts of nasal septum are removed and rest of the parts are surgically corrected and repositioned.
- Submucous resection ( SMR ) : Mucoperiosteal and mucoperichondral flaps that overlie one side of the septum are lifted. Most of the septum is removed and flaps repositioned.
Hope this helped :)
- Jaskunwar Singh
External Carotid Artery branches mnemonic - Seven Angry Ladies Fighting Over PMS
Superior Thyroid - Anterior branch
Ascending Pharyngeal - Medial
Lingual - Anterior
Facial - Anterior
Occipital - Posterior
Posterior auricular - Posterior
Maxillary - terminal
Superficial Temporal - terminal
Submitted by - Chaitanya Inge
The CN III has both motor (central) and parasympathetic (peripheral) components.
Which fibers get affected in diabetes?
Which would lead to loss of pupillary light reflex?
Which fibers are compressed first?
Which would cause the down and out pupil?
Don't know? Check the video out!
The clinical features ( s/s ) that are presented by a patient with DNS are : NOSE MASH
NO - Nasal Obstruction
S - Septal cartilage and bone deformity
E - Epistaxis
M - Middle Ear infection
A - Anosmia
S - Sinusitis
H - Headache
- Jaskunwar Singh
In this post, I will be talking about the middle ear structures and its relations with its neighbors ( just a summary ).
The Middle Ear is an air filled and bilaterally compressed/ concaved cavity lined by mucous membrane located in between the external and internal parts of ear. It is divided into:
- Epitympanum or the Attic ( 6mm ) - lies above pars tensa and medial to pars flaccida
- Mesotympanum ( 2mm ) - lies opposite to pars tensa
- Hypotympanum ( 4mm ) - lies below the level of pars tensa
BOUNDARIES of the middle ear ( homologous to structure of a cube ) :-
Roof : Tegmen tympani - a thin bony plate that is a part of petrous part of temporal bone, separates the middle ear cleft from middle cranial fossa.
- Infection in the middle ear may spread superiorly and lead to formation of abscess in the meninges ( especially Extradural abscess ), meningitis or if severe, it may even lead to abscess formation in the temporal lobe.
Floor : Jugular bulb - The middle ear cavity is separated from jugular bulb by a thin piece of bone that if deficient may lead to formation of a layer of fibrotic tissue and mucous membrane in between. The contents of jugular bulb are:
- Internal Jugular vein
- Glossopharyngeal nerve ( IX )
- Vagus ( X )
- Accessory nerve ( XI )
The tympanic branch of glossopharyngeal nerve enters the middle ear at the junction of the floor and medial wall to play an important role in formation of tympanic plexus.
Anterior wall : The upper part of the narrow anterior wall has two openings or tunnels for -
- Canal for Tensor tympani muscle
- Pharyngotympanic ( or Eustachian ) tube
The lower part of anterior wall is separated from the Internal Carotid artery by a thin plate of bone. The ICA is surrounded by a plexus of sympathetic nerves that enter middle ear through openings in this bony plate to form tympanic plexus.
Posterior wall : Posteriorly, it is related to middle ear cleft ( Aditus, Antrum and mastoid air cells )
- Infection in this region may spread posteriorly into the sigmoid sinus ( in posterior cranial fossa ) and cause thrombophlebitis !!
Medial wall : Medially the middle ear cavity is related to the promontory, oval and round window
Lateral wall : Tympanic membrane separates the middle ear from the external ear.
A brief about the functions of middle ear:
On the incoming of sound waves, the tympanic membrane oscillates and these oscillations are sensed by the strongly attached and faithful middle ear ossicle, the Malleus. The sound energy is transmitted as such by the ossicles ( Malleus - Incus - Stapes ) to the internal ear for further processing.
The major function of these ossicles is amplification of sound waves - Tympanic membrane is 17 times larger than the oval window - So that means the sound energy is picked up by the larger area ( TM ) and impinged over a much smaller area ( oval window ) thus amplifying it 17 times.
In addition, the lever action of the ossicular chain is approx. 1.3 units. Thus the intensity ( force ) of sound waves/ vibrations changes ( increased by ~20 times ) and not the frequency !! If the sound waves are not amplified ( in case OC is removed ), the Air Conduction would be lost. So BC > AC and thus hearing would then be poor.
Hope this helped :)
- Jaskunwar Singh
Monday, April 24, 2017
The C's of Craniopharyngioma
Central diabetes insipidus
Compresses chiasm, can't C (see, because butemporal hemianopia)
CR: CRAniopharyngioma RAthkes pouch remnant
Yup. That's all!
Sunday, April 23, 2017
Hi everyone. So JVP is one of the most theoretical clinical signs I've ever studied. And though parts of it are logical , I find it tedious to memorize all causes for a particular finding.
So I've prepared a Mnemonic for prominent a waves.
The A wave is a positive wave of the JVP.
It represents the Right Atrial pressure during systole.
Causes of a prominent a wave
C - Cor Pulmonale
R - Right heart Failure
P - Pulmonary stenosis
T - Tricuspid stenosis
S - The S tells you it's Stenosis for P and T.
The a wave essentially represents the pressure in the Right atrium during systole.
So any condition that causes this pressure to increase would cause a prominent A wave.
Cor Pulmonale and RVF are basically congestion in RV causing elevation of pressure in the RV.
This means the atrium needs to pump with greater force into the Ventricle for the venous return to enter the Ventricle. This increases the RA pressure causing prominent a wave.
Pulmonary Stenosis leads to accumulation of blood in the RV and this follows a similar fate as the above mentioned causes.
Tricuspid stenosis causes obstruction to the flow of blood from RA to RV. Thus accentuating the pressure in the RA.
That's the Prominent a wave for you !
Now there's something called the Cannon a wave.
These represents contraction of the RA against a closed Tricuspid valve.
The causes of this include -
A- V dissociation.
Ventricular arrhythmias - V tach , Ventricular premature complexes and Ventricular pacing.
The a wave would be absent in Atrial fibrillation as the atrium is functionally not pumping at all , and just vibrating.
These are the a wave findings for you !
Hope this helped
~ A.P. Burkholderia
Number needed to treat = 1 / Absolute risk reduction
Mnemonic: TARR - Treat Absolute Risk Reduction
Number needed to harm = 1 / Attributable risk
Mnemonic: HARM - Harm Attributable Risk M
This is a short post on why clubbing happens.
So it's simple !
It's cause people like to go out and get drunk.
Just kidding. Here goes.
- It's the bulbous enlargement of the terminal digits and the nail bed.
- Symmetrical clubbing can occur due to a host of causes.
- To summarize :
: Lung cancer
: Suppurative lung conditions like
: Pulmonary Fibrosis
- Cyanotic heart disease
- Eisenmenger Syndrome
- Infective endocarditis
- Inflammatory bowel disease
- Cirrhosis - esp Biliary
- Thyroid Acropachy
But what makes sense to me , I want to share with you'll! And it was an absolute pain to find something convincing enough. So just stick with me here ;;)
The most widely accepted theory right now is the megakaryocyte theory.
IBD - especially Crohn disease seen to have thrombocytosis eventually which may aggravate the PDGF.
In cirrhosis of liver , especially biliary , pulmonary arteriovenous shunting is observed. This could result in the megakaryocyte entrapment as explained.
Another theory suggests inflammation triggers a vagal response causing Vasodilator effects. ( Neurogenic).
Other theories -
Reduced ferritin related
Humoral - various PG's and other humoral molecules.
The most widely accepted theory is the Megakaryocyte theory.
Hope this satisfied you !
Saturday, April 22, 2017
In this video, I show how I keep my camera stable while shooting videos of my notes / whiteboard.
I use paper cups and books as my camera stand.
Friday, April 21, 2017
(The palmar ridges are accentuated and resemble to the stomach mucosa of a ruminant-tripe.)
Hi everyone. Just a list of changes you can see in the nails in different systemic Diseases. So let's get nailed ;)
1. Clubbing -
Loss of angle between the nail and the nail fold - More soft and bulbous nail.
Typically indicates Cardio Pulmonary function disturbance :
--> Cardiac conditions like Cyanotic heart disease, Infective endocarditis and Atrial myxoma.
--> Respiratory conditions :
Neoplastic like CA lung ( Esp. Squamous cell CA) , Mesothelioma.
Infective like Bronchiectasis , Abscess , Empyema.
(Non cardiorespiratory causes = Inflammatory bowel disease, Biliary Cirrhois.
Thyroid Acropachy , Acromegaly. )
2. Koilonychia -
Spoon shaped nails.
Strongly indicative of Iron Deficiency anemia or Fungal nail infection.
3. Onycholysis -
Destruction of nail.
Seen in Psoriasis , Hyperthyroid and Fungal nail infection.
4. Chronic Paronychia -
Inflammation of nail fold. May have swollen nail and discharge with throbbing pain. May occur due to frequent nail biting.
5. Cyanosis -
Can be looked for in nail bed. We have a post on this already.
6. Beau line -
Transverse furrows from temporary arrest of nail growth due to increased stress.
Nails grow at 0.1 mm/d , so furrow distance from the cuticle can be used to time the attack. Can be seen in Malaria , Typhus , Rheumatic fever , Kawasaki.
7. Mees line -
White transverse bands in Arsenic poisoning / Renal failure.
8. Muerhcke's line -
White parallel lines without furrowing on the nail.
Seen in Hypoalbuminemia.
9. Terry's nails -
Proximal portion of nail is white / pink , tip is reddish brown.
Seen in cirrhosis , CRF
10. Splinter hemorrhage -
Longitudinal Hemorrhage streaks under the nail seen in Infective endocarditis.
What a fun way to get nailed down 😂 Happy studying !