MRCS 1 Flashcards
(94 cards)
1
Q
Control of ventilation
A
Control of ventilation is coordinated by the respiratory centres, chemoreceptors, lung receptors and muscles
Automatic, involuntary control of respiration occurs from the medulla.
The respiratory centres control the respiratory rate and the depth of respiration.
2
Q
Respiratory centres
A
Medullary respiratory centre
Inspiratory and expiratory neurones. Has ventral group which controls forced voluntary expiration and the dorsal group controls inspiration. Depressed by opiates.
Apneustic centre
Lower pons
Stimulates inspiration - activates and prolongs inhalation
Overridden by pneumotaxic control to end inspiration
Pneumotaxic centre
Upper pons, inhibits inspiration at a certain point. Fine tunes the respiratory rate.
3
Q
Ventillatory variables
A
Levels of pCO2 most important in ventilation control
Levels of O2 are less important.
4
Q
Peripheral chemoreceptors location and what do they respond to
A
Peripheral chemoreceptors: located in the bifurcation of carotid arteries and arch of the aorta. They respond to changes in reduced pO2, increased H+ and increased pCO2 in ARTERIAL BLOOD.
5
Q
Central chemoreceptors location and what do they respond to
A
Central chemoreceptors: located in the medulla. Respond to increased H+ in BRAIN INTERSTITIAL FLUID to increase ventilation.
NB the central receptors are NOT influenced by O2 levels.
6
Q
Lung receptors
A
include:
Stretch receptors: respond to lung stretching causing a reduced respiratory rate
Irritant receptors: respond to smoke etc causing bronchospasm
J (juxtacapillary) receptors
7
Q
Hypercalcaemia - main causes?
A
Malignancy (most common cause in hospital in-patients)
Primary hyperparathyroidism (commonest cause in non hospitalised patients)
Less common
Sarcoidosis (extrarenal synthesis of calcitriol )
Thiazides, lithium
Immobilisation
Pagets disease
Vitamin A/D toxicity
Thyrotoxicosis
MEN
Milk alkali syndrome
8
Q
Hypercalcaemia Clinical features?
A
Stones, bones, abdominal groans, and psychic moans
There are clinical features such as bone pain, osteoporosis, fatigue, confusion, memory problems, depression, nausea, vomiting, abdominal pain, weight loss, thirst, polyuria, constipation, abdominal pain, renal colic, or renal impairment. Symptoms and signs are often non-specific, and relate to the severity and rate of onset of hypercalcaemia.
High serum calcium levels result in decreased neuronal excitability. Therefore sluggish reflexes, muscle weakness and constipation may occur.
9
Q
Myocardial action potential
A
0 Rapid depolarisation Rapid sodium influx
These channels automatically deactivate after a few ms
1 Early repolarisation Efflux of potassium
2 Plateau Slow influx of calcium
3 Final repolarisation Efflux of potassium
4 Restoration of ionic concentrations Resting potential is restored by Na+/K+ ATPase
There is slow entry of Na+ into the cell decreasing the potential difference until the threshold potential is reached, triggering a new action potential
10
Q
Conduction velocity
A
Atrial conduction - Spreads along ordinary atrial myocardial fibres at 1 m/sec
AV node conduction - 0.05 m/sec
Ventricular conduction Purkinje fibres are of large diameter and achieve velocities of 2-4 m/sec (this allows a rapid and coordinated contraction of the ventricles
11
Q
Large villous adenomas? common electrolyte abnormality
A
Large villous adenomas of the rectum may have marked secretory activity and result in the development of hypokalaemia as rectal secretions are rich in potassium.
12
Q
Which medications can cause SIADH
A
SIADH - drug causes: sulfonylureas SSRIs, tricyclics carbamazepine vincristine cyclophosphamide
13
Q
Where is the vomiting centre located?
A
medulla oblongata
Reflex oral expulsion of gastric (and sometimes intestinal) contents - reverse peristalsis and abdominal contraction
The vomiting centre is in part of the medulla oblongata and is triggered by receptors in several locations
14
Q
Non- GI causes of vomiting
A
ABC’s of Non- GI causes of vomiting
Acute renal failure DKA Brain (Increased ICP) Cardiac (Inferior MI) Ears (labyrinthitis) Foreign substances (Tylenol, theo, etc) Glaucoma Hyperemesis Gravidarum Infections (pyelonephritis, meningitis)
15
Q
Where are the receptors which trigger vomiting?
A
The vomiting centre is in part of the medulla oblongata and is triggered by receptors in several locations
Labyrinthine receptors of ear (motion sickness)
Over distention receptors of duodenum and stomach
Trigger zone of CNS - many drugs (e.g., opiates) act here
Touch receptors in throat
16
Q
PTH half life?
A
PTH has a very short half life usually less than 10 minutes
Therefore a demonstrable drop in serum PTH should be identified within 10 minutes of removing the adenoma. This is useful clinically since it is possible to check the serum PTH intraoperatively prior to skin closure and explore the other glands if levels fail to fall.
17
Q
lung compliance
A
Lung compliance is defined as change in lung volume per unit change in airway pressure
Causes of increased compliance
age
emphysema - this is due to loss of alveolar walls and associated elastic tissue
Causes of decreased compliance pulmonary oedema pulmonary fibrosis pneumonectomy kyphosis
18
Q
4 Types of opioid receptor
A
4 Types of opioid receptor:
δ (located in CNS)- Accounts for analgesic and antidepressant effects
k (mainly CNS)- analgesic and dissociative effects
µ (central and peripheral) - causes analgesia, miosis, decreased gut motility
Nociceptin receptor (CNS)- Affect of appetite and tolerance to µ agonists.
19
Q
Drugs causing SIADH: ABCD
A
A nalgesics: opioids, NSAIDs
B arbiturates
C yclophosphamide/ Chlorpromazine/ Carbamazepine
D iuretic (thiazides)
20
Q
causes of hypercalcaemia
A
Main causes
Malignancy (most common cause in hospital in-patients)
Primary hyperparathyroidism (commonest cause in non hospitalised patients)
CHIMPANZEES
C alcium supplementation H yperparathyroidism I atrogentic (Drugs: Thiazides) M ilk Alkali syndrome P aget disease of the bone A cromegaly and Addison's Disease N eoplasia Z olinger-Ellison Syndrome (MEN Type I) E xcessive Vitamin D E xcessive Vitamin A S arcoidosis
21
Q
Obesity hormones
leptin
ghrelin
A
leptin decreases appetite
ghrelin increases appetite
22
Q
TI resection may cause malabsorption of bile salts ? management
A
The question is about high output diarrhoea following terminal ileal resection and the most likely cause is malabsorption of bile salts
he administration of cholestyramine (bile salt binding agent) will counter this
23
Q
Conns syndrome
A
Excessive production of aldosterone
Leads to hypokalemia, hypertension/water(Na) retention
24
Q
pre renal uraemia vs ATN
A
Prerenal uraemia - kidneys retain sodium to preserve volume
Pre-renal uraemia Acute tubular necrosis Urine sodium < 20 mmol/L > 30 mmol/L Fractional sodium excretion* < 1% > 1% Fractional urea excretion** < 35% >35% Urine:plasma osmolality > 1.5 < 1.1 Urine:plasma urea > 10:1 < 8:1 Specific gravity > 1020 < 1010 Urine 'bland' sediment brown granular casts Response to fluid challenge Yes No
25
Normal Gap Acidosis: HARDUP
```
H - Hyperalimentation/hyperventilation
A - Acetazolamide
R - Renal tubular acidosis
D - Diarrhoea
U - Ureteral diversion
P - Pancreatic fistula/parenteral saline
```
26
Inhibition of insulin release:
Alpha adrenergic drugs
Beta blockers
Sympathetic nerves
27
carbimazole mechanism of action
Thionamides group.
Carbimazole is a pro-drug as after absorption it is converted to the active form, methimazole.
Inhibits thyroid hormone production via inhibition of thyroid peroxidase → blockade of iodide oxidation, organification, coupling
28
Potassium iodides - MOA
Lugol's iodine (oral potassium iodide)
Saturated solution of potassium iodide (SSKI
Inhibit proteolytic cleavage of T3 and T4 from thyroglobulin→ inhibits thyroid hormone release
Also decrease thyroid vascularity and decrease the size of the gland
29
Glucocorticoids MOA
Glucocorticoids exert their effects by binding intracellular receptors that are then transported to the nucleus where they affect gene transcription.
Glucocorticoids reduce inflammation through a combination of both inhibition & upregulation of gene transcription, including: INHIBITION of genes regulating expression of: COX-2
30
Corticosteroids - how are they synthesised
Synthesised from cholesterol within the adrenal cortex
31
Effects of glucocorticoids
Metabolic (generally oppose those of insulin):
- breakdown of protein to amino acids (increased protein catabolism)
- amino acids then converted to glucose (gluconeogenesis)
- storage of glucose as glycogen
- lipolysis: mobilised free fatty acids and glycerol: these are then converted to glucose in the liver
Regulatory actions
- Has a negative feedback action on the hypothalamus causing reduced release of endogenous glucocorticoids
- Within the CVS they cause decreased vasodilation and decreased fluid exudation
- They decrease osteoblastic activity and increase osteoclastic activity
- Decrease acute and chronic inflammation (decrease in influx and activity of leukocytes), decreased clonal expansion of B and T lymphocytes.
32
ECG features in hypokalemia
```
U waves
Small or absent T waves (occasionally inversion)
Prolonged PR interval
ST depression
Long QT interval
```
One registered user suggests the following rhyme!
In Hypokalaemia, U have no Pot and no T, but a long PR and a long QT!
33
Recklinghausen's disease
Neurofibromatosis 1 (NF1)
autosomal dominant disorder
caused by the mutation of a gene on chromosome 17
NF-1 causes tumors along the nervous system which can grow anywhere on the body
NF1, benign tumors called neurofibromas cover the peripheral nerve and, similarly, may cause pain or specific neurologic symptom
34
NF1 vs NF2
NF2 is caused by a mutation on chromosome 22 and involves a protein called merlin, which is thought to be involved in cell shape and structure.
NF1 - chromosome 17.
Individuals with NF2 do not have learning disabilities, a complication that is very commonly seen in people with NF1.
In NF2, benign tumors called schwannomas grow on nerves throughout the nervous system and often cause impaired hearing and vision.
NF1, benign tumors called neurofibromas cover the peripheral nerve and, similarly, may cause pain or specific neurologic symptom
Symptoms of NF2 are typically detected between the ages of 18 and 24 years, while NF1 is diagnosed in infancy or early childhood.
35
Li-Fraumeni syndrome (LFS)
- ALSO KNOWN AS SBLA syndrome (the sarcoma, breast, leukaemia and adrenal gland) .
- AUTOSOMAL DOMINANT
- linked to germline mutations of the p53 tumor suppressor gene
- predisposes carriers to cancer development
- Li–Fraumeni syndrome is diagnosed if these three criteria are met:
The patient has been diagnosed with a sarcoma at a young age (below 45).
A first-degree relative has been diagnosed with any cancer at a young age (below 45).
Another first- or a second-degree relative has been diagnosed with any cancer at a young age (below 45) or with a sarcoma at any age.
36
Pierre Robin syndrome
- small lower jaw (micrognathia)
- glossoptosis (displacement of the tongue toward the back of the oral cavity)
- can have cleft palate
37
Kartagener's syndrome
- AUTOSOMAL RECESSIVE genetic disorder
| - ciliary disorder comprising the triad of situs inversus, chronic sinusitis, and bronchiectasis.
38
BRCA 1 and 2
- Carried on chromosome 17 (BRCA 1) and Chromosome 13 (BRCA 2)
- Linked to developing breast cancer (60%) risk.
- Associated risk of developing ovarian cancer (55% with BRCA 1 and 25% with BRCA 2).
39
Lynch Syndrome
- Also known as hereditary non-polyposis colorectal cancer (HNPCC) syndrome
- AUTOSOMAL DOMINANT
- Microsatellites instability affecting DNA mismatch repair genes
- high risk of colonic cancer as well as endometrial cancer. (80% of affected individuals will get colonic and/ or endometrial cancer)
- develop colonic cancer and endometrial cancer at a young age.
- High risk individuals may be identified using the Amsterdam criteria (3-2-1)
40
What is amsterdam criteria?
Amsterdam criteria (3-2-1)
Three or more family members with a confirmed diagnosis of colorectal cancer, one of whom is a first degree (parent, child, sibling) relative of the other two.
Two successive affected generations.
One or more colon cancers diagnosed under age 50 years.
Familial adenomatous polyposis (FAP) has been excluded.
41
Gardners syndrome
Autosomal dominant familial colorectal polyposis
Multiple colonic polyps:
FAP + DESMOID tumours (15%) and mandibular osteomas
Extra colonic diseases include: skull osteoma, thyroid cancer and epidermoid cysts
Mutation of APC gene located on chromosome 5
Due to colonic polyps most patients will undergo colectomy to reduce risk of colorectal cancer
42
FAP
- AUTOSOMAL DOMINANT
- 25% de novo
- usually APC affected (adenomatous polyposis coli)
- 100 adenom. polyps - colon/rectum; duodenal fund. glandular polyps
- 100% risk of colorectal ca
43
Puetz-Jegers
- AUTOSOMAL DOMINANT genetic condition
- mutations in the STK11(70%)/LKB1 gene
- benign HAMARTOMOUS POLYPS in the GI tract + HYPERPIGMENTED MACULES on the lips and oral mucosa (melanosis)
- Increased risk of developing carcinomas of the liver, lungs, breast, ovaries, uterus, testes and other organs
44
Cowden's disease
- AUTOSOMAL DOMINANT genetic condition.
- PTEN (85%) (tumour suppressor gene and loss of function mutations result in up regulation of the mTOR pathway.)
- MULTIPLE HAMARTOMAS.
- increased lifetime risk of breast, thyroid, uterine, and other cancers
45
3 types of neuronal injury
Neuropraxia, axonotmesis, neurotmesis
```
Neuropraxia
Nerve intact but electrical conduction is affected
Full recovery
Autonomic function preserved
Wallerian degeneration does not occur
```
Axonotmesis
Axon is damaged and the myelin sheath is preserved. The connective tissue framework is not affected.
Wallerian degeneration occurs.
Neurotmesis
Disruption of the axon, myelin sheath and surrounding connective tissue.
Wallerian degeneration occurs.
46
What is Wallerian Degeneration
Axonal degeneration distal to the site of injury.
Typically begins 24-36 hours following injury.
Axons are excitable prior to degeneration occurring.
Myelin sheath degenerates and is phagocytosed by tissue macrophages.
47
Nerve repair
Neuronal repair may only occur physiologically where nerves are in direct contact. Where a large defect is present, the process of nerve regeneration is hampered. It may not occur at all or result in the formation of a neuroma. Where nerve regrowth occurs it is typically at a rate of 1mm per day.
48
Pituitary Gland
The pituitary gland is located within the sella turcica within the sphenoid bone in the middle cranial fossa. It is covered by a dural fold and weighs around 0.5g. It is attached to the hypothalamus by the infundibulum. The anterior pituitary receives hormonal stimuli from the hypothalamus by way of the hypothalamo-pituitary portal system. It develops from a depression in the wall of the pharynx (Rathkes pouch).
49
Anterior pituitary hormones
```
Growth hormone
Thyroid stimulating hormone
ACTH
Prolactin
LH and FSH
Melanocyte releasing hormone
```
50
Posterior pituitary hormones
Oxytocin
| Anti diuretic hormone
51
Menetriers disease
Gross hypertrophy of the gastric mucosal folds, excessive mucous production and hypochlorhydria
Pre malignant condition
52
Reflux gastritis
Bile refluxes into stomach, either post surgical or due to failure of pyloric function
Histologically, evidence of chronic inflammation, and foveolar hyperplasia
May respond to therapy with prokinetics
53
Erosive gastritis
Agents disrupt the gastric mucosal barrier
Most commonly due to NSAIDs and alcohol
With NSAIDs the effects occur secondary to COX 1 inhibition
54
Type A ant type B gastritis
Type A gastritis - Autoimmune
Circulating ANTIBODIES TO PARIETAL CELLS, causes reduction in cell mass and hypochlorhydria
Loss of parietal cells = loss of intrinsic factor = B12 malabsorption
ANTRUM NON INVOLVED
Hypochlorhydria causes elevated gastrin levels- stimulating enterochromaffin cells and adenomas may form
TYPE B gastritis - associated with infection with H PYLORI
Antral gastritis
Intestinal metaplasia may occur in stomach and require surveillance endoscopy
Peptic ulceration may occur
55
Sarcomas in which Lymphatic Metastasis is seen
'RACE For MS'
```
R: Rhabdomyosarcoma
A: Angiosarcoma
C: Clear cell sarcoma
E: Epithelial cell sarcoma
For: Fibrosarcoma
M: Malignant fibrous histiocytoma
S: Synovial cell sarcoma
```
56
How do sarcomas mts?
Sarcomas often metastasise via the haematogenous route.
Lung is a common site for sarcoma metastasis. The liver and brain are often spared (at least initially). A smaller number may develop lymphatic metastasis
57
Which nerve is responsible for the motor innervation of the sternocleidomastoid muscle?
Spinal root of accessory nerve (XI)
58
Anterior interosseous nerve classically innervates?
The anterior interosseous nerve classically innervates 2.5 muscles:
Flexor pollicis longus
Pronator quadratus
The radial half of flexor digitorum profundus (the lateral two out of the four tendons).
59
Carcinoid syndrome
Carcinoid tumours secrete serotonin
Originate in neuroendocrine cells mainly in the intestine (midgut-distal ileum/appendix)
Can occur in the rectum, bronchi
Hormonal symptoms mainly occur when disease spreads outside the bowel
Clinical features
Onset: insidious over many years
Flushing face
Palpitations
Pulmonary valve stenosis and tricuspid regurgitation causing dyspnoea
Asthma
Severe diarrhoea (secretory, persists despite fasting)
```
Investigation
5-HIAA in a 24-hour urine collection
Somatostatin receptor scintigraphy
CT scan
Blood testing for chromogranin A
```
Treatment
Octreotide
Surgical removal
60
AXILLARY ARTERY - PARTS
| AND BRANCHES
>from the outer border of the first rib to the lower border of teres major, where it becomes the brachial artery. Subdivided into three zones IN RELATION TO PECTORALIS MINOR
>>the first part lies above pectoralis minor,
>>the second part is behind the muscle
>> third part lies inferior to it
The superior thoracic artery is the first branch of the axillary artery that arises from the first part
Two branches arise from the second part, thoraco acromial and lateral thoracic
Three branches from the third part, subscapular artery, anterior and posterior circumflex humeral arteries
```
>>Mnemonic for axillary artery branches
Screw The Lawyer Save A patient
Superior thoracic artery
Thoracoacromial artery
Lateral thoracic artery
Subscapular artery
Anterior humeral circumflex artery
Posterior humeral circumflex artery
```
61
The jugular foramen CONTENTS
Temporal bone
Jugular foramen may be divided into three compartments:
Anterior: inferior petrosal sinus
Intermediate: glossopharyngeal, vagus, and accessory nerves
Posterior: sigmoid sinus (becoming the internal jugular vein) and some meningeal branches from the occipital and ascending pharyngeal arteries
62
Scalene muscles
The 3 paired muscles are:
Scalenus anterior: Elevate 1st rib and laterally flex the neck to same side
Scalenus medius: Same action as scalenus anterior
Scalenus posterior: Elevate 2nd rib and tilt the cervical spine
Origin Transverse processes C2 to C7
Insertion 1st and 2nd ribs
63
Important anatomical relations - scalene muscles
| brachial plexus, subclavian artery, phrenic nerve, subclavian vein
Important relations
The brachial plexus and subclavian artery pass between the anterior and middle scalenes through a space called the scalene hiatus/fissure.
The subclavian vein and phrenic nerve pass anteriorly to the anterior scalene as it crosses over the first rib.
64
Ewing's sarcoma
- Paediatric Malignant ROUND CELL tumour
- Occurs in the diaphysis of the long bones
- These are not confined to the ends of long bones.
- X- Rays - ONION PEEL SIGN (large soft-tissue mass with concentric layers of new bone formation).
- ESR may be elevated
- Treatment - chemotherapy and surgical excision, an endoprosthesis may be used to conserve the limb.
65
Brachial plexus POSTERIOR cord branches
```
STAR
S ubscapular (upper and lower)
T horacodorsal
A xillary
R adial
```
66
Trendelenburg test
Damage to the SUPERIOR GLUTEAL NERVE DAMAGE will result in a Trendelenburg gait.
Injury or division of the superior gluteal nerve results in a motor deficit that consists of weakened abduction of the thigh by gluteus medius, a disabling gluteus medius limp and a compensatory list of the body to the weakened gluteal side. The compensation results in a gravitational shift so that the body is supported on the unaffected limb.
When a person is asked to stand on one leg, the gluteus medius usually contracts as soon as the contralateral leg leaves the floor, preventing the pelvis from dipping towards the unsupported side. When a person with paralysis of the superior gluteal nerve is asked to stand on one leg, the pelvis on the unsupported side descends, indicating that the gluteus medius on the affected side is weak or non functional ( a positive Trendelenburg test).
This eponymous test also refers to a vascular investigation in which tourniquets are placed around the upper thigh, these can help determine whether saphenofemoral incompetence is present.
67
Which cancers HPV is associated with
1. Cervical cancer (HPV 16/18 most common)
2. Anal cancer
3. Penile cancer
4. Vulval cancer
5. Oropharyngeal cancer
68
Subclavian steal syndrome
characteristically presents with posterior circulation symptoms, such as dizziness and vertigo, during exertion of an arm. There is subclavian artery steno-occlusive disease proximal to the origin of the vertebral artery and is associated with flow reversal in the vertebral artery. Management involves percutaneous transluminal angioplasty or a stent.
69
Barretts oesophagus is associated with which type of oesophageal ca ?
Barretts oesophagus is most closely associated with adenocarcinoma, and it confers a 30 fold increased risk of developing the condition.
70
Muscles innervated by the musculocutaneous nerve
BBC:
Biceps brachii
Brachialis
Coracobrachialis
71
femoral nerve supply
(don't) M I S V Q Scan for PE
M edial cutaneous nerve of the thigh
I ntermediate cutaneous nerve of the thigh
S aphenous nerve
V astus
Q uadriceps femoris
S artorius
PE ectineus
72
Von Hippel-Lindau syndrome
Von Hippel-Lindau (VHL) syndrome is an autosomal dominant condition predisposing to neoplasia. It is due to an abnormality in the VHL gene located on short arm of chromosome 3
Features
cerebellar haemangiomas
retinal haemangiomas: vitreous haemorrhage
renal cysts (premalignant)
phaeochromocytoma
extra-renal cysts: epididymal, pancreatic, hepatic
endolymphatic sac tumours
73
Abdominal aorta branches and levels
```
inferior phrenic - T12 - parietal
coeliac - T12 - visceral
SMA L1 - Visceral
Middle suprarenal L1 - Visceral
Renal L1-2 - Visceral
Gonadal L2 - Visceral
IMA L3 - Visceral
Lumbar L1-4 - Parietal
Median sacral - L4 - parietal
common iliacs - L4 - terminal
```
74
Antiphospholipid syndrome
Anti phospholipid syndrome= following antibodies
Lupus anticoagulant
Anti-cardiolipin
Anti-β2-glycoprotein
Antiphospholipid syndrome, is an autoimmune, hypercoagulable state caused by antiphospholipid antibodies. APS provokes blood clots (thrombosis) in both arteries and veins as well as pregnancy-related complications such as miscarriage, stillbirth, preterm delivery, or severe preeclampsia.
The diagnostic criteria requires one clinical event, i.e. thrombosis or pregnancy complication, and two positive blood tests spaced at least 3 months apart. These antibodies are: lupus anticoagulant, anti-cardiolipin and anti-β2-glycoprotein.
Antiphospholipid syndrome can be primary or secondary. Primary antiphospholipid syndrome occurs in the absence of any other related disease. Secondary antiphospholipid syndrome occurs with other autoimmune diseases, such as systemic lupus erythematosus (SLE). In rare cases, APS leads to rapid organ failure due to generalised thrombosis; this is termed catastrophic antiphospholipid syndrome (CAPS) and is associated with a high risk of death.
Antiphospholipid syndrome often requires treatment with anticoagulant medication such as heparin to reduce the risk of further episodes of thrombosis and improve the prognosis of pregnancy. Warfarin is not used during pregnancy because it can cross the placenta, unlike heparin, and is teratogenic.
75
Which structure attaches periosteum to bone?
Periosteum is attached to bone by strong collagenous fibers called Sharpey's fibres, which extend to the outer circumferential and interstitial lamellae. It also provides an attachment for muscles and tendons.
76
Three cranial nerves may be injured during submandibular gland excision.
Marginal mandibular branch of the facial nerve
Lingual nerve
Hypoglossal nerve
77
Blood film in hyposplenism features
```
Howell-Jolly bodies
Pappenheimer bodies
Poikilocytes (Target cells)
Erythrocyte containing siderotic granules
Heinz bodies
```
78
Tuberous sclerosis
AUTOSOMAL DOMINANT genetic condition.
Mostly neurocutaneous features.
CUTANEOUS
- 'ash-leaf' spots (fluoresce under UV light)
- roughened patches of skin over lumbar spine (Shagreen patches)
- adenoma sebaceum: butterfly distribution over nose
fibromata beneath nails (subungual fibromata)
- café-au-lait spots* may be seen
NEUROLOGICAL
- developmental delay
- epilepsy (infantile spasms or partial)
- intellectual impairment
ALSO:
- retinal hamartomas: dense white areas on retina (phakomata)
- rhabdomyomas of the heart
- gliomatous changes can occur in the brain lesions
- polycystic kidneys, renal angiomyolipomata
79
In the distal third of the upper arm, where is the musculocutaneous nerve located?
The musculocutaneous nerve lies between the biceps and brachialis muscles.
80
Musculocutaneous nerve
Which cord of brachial plexus
Which muscles does it innervate
Branch of lateral cord of brachial plexus
Innervates
Coracobrachialis
Biceps brachii
Brachialis
81
Musculocutaenous nerve
| pathway
It penetrates the coracobrachialis muscle
Passes obliquely between the biceps brachii and the brachialis to the lateral side of the arm
Above the elbow it pierces the deep fascia lateral to the tendon of the biceps brachii
Continues into the forearm as the lateral cutaneous nerve of the forearm
82
Deep perineal pouch borders
The deep pouch is now described as the region between the perineal membrane and the pelvic diaphragm.
INFERIORLY: by the perineal membrane (the inferior fascia of the urogenital diaphragm).
SUPERIORLY: by the superior fascia of the urogenital diaphragm.
This fascial boundary extends laterally to form the medial wall of the ischiorectal fossa. The pouch is bounded superiorly by the superior fascia of the urogenital diaphragm and this lies beneath the levator ani muscle.
83
Deep perineal pouch content
```
membranous part or urethra
sphincter urethrae muscle
bulbourethral glands
deep transverse perineal muscles
internal pudendal vessels and their branches
dorsal nerves of penis
```
84
Which amino -acid is present in collagen?
GLYCINE
Collagen has a generic structure of Glycine- X- Y, where X and Y are variable sub units. The relatively small size of the glycine molecule enables collagen to form a tight helical structure.
85
Lateral hip rotators
```
P-GO-GO-Q (top to bottom)
Piriformis
Gemellus superior
Obturator internus
Gemellus inferior
Obturator externus
Quadratus femoris
```
86
Horners syndrome
```
Horners syndrome, clinical features:
Ptosis
Miosis
Enopthalmos
Anhydrosis
```
Primarily a disorder of the sympathetic nervous system. Extent of symptoms depends upon the anatomical site of the lesion.
Proximal lesions occur along the hypothalamospinal tract
Distal lesions are usually post ganglionic e.g. at level of internal carotid artery or beyond.
87
Median arcuate ligament syndrome (MALS)
*diagnosis of exclusion
Symptoms/findings (in some patients):
- epigastric pain
- audible bruit
Where the condition is suspected, the diagnosis is usually apparent on duplex scanning (in thin patients) or with CT angiography.
MALS is treated by cutting the median arcuate ligament so that it can't compress the celiac artery and surrounding nerves anymore.
88
Cranial venous sinuses
```
located within the dura mater. They have no valves which is important in the potential for spreading sepsis. They eventually drain into the internal jugular vein.
They are:
- Superior sagittal sinus
- Inferior sagittal sinus
- Straight sinus
- Transverse sinus
- Sigmoid sinus
- Confluence of sinuses
- Occipital sinus
- Cavernous sinus
```
89
MEN IIB features
```
Associated with RET oncogene (chromosome 10)
Features:
Phaeochromocytoma
Medullary thyroid cancer
MUCOSAL NEUROMA
MARFANOID APPEARANCE
```
90
MEN type IIa features
```
Associated with RET oncogene (chromosome 10)
Features:
Phaeochromocytoma
Medullary thyroid cancer (70%)
Hyperparathyroidism (60%)
```
91
MEN type I features
Associated with MENIN gene (chromosome 11)
Most common presentation = hypercalcaemia
Features (Mnemonic 'three P's':)
Parathyroid (95%): Parathyroid adenoma
Pituitary (70%): Prolactinoma/ACTH/Growth Hormone secreting adenoma
Pancreas (50%): Islet cell tumours/Zollinger Ellison syndrome
also: Adrenal (adenoma) and thyroid (adenoma)
92
Berrys sign
Absence of carotid pulse due to malignant thyromegaly.
93
Subclavian steal syndrome
Subclavian steal syndrome is associated with a stenosis or occlusion of the subclavian artery, proximal to the origin of the vertebral artery.
As a result, the increased metabolic needs of the arm then cause retrograde flow and symptoms of CNS vascular insufficiency.
94
Rectum blood supply
The rectum is supplied by 3 main vessels
Superior rectal artery from inferior mesenteric artery
Middle rectal artery from the internal iliac artery
Inferior rectal artery from the internal pudendal artery
