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Flashcards in Anatomy Deck (114):

Which muscle of the tongue is not innervated by XII cranial nerve?

Palatoglossus muscle (X CN)


Which structure must ligate the surgeon to prevent massive hemorrhage during oophorectomy?. Which structure should be identified prior to ligate?

- Suspensory ligament of the ovary▶️content ovarian artery, vein, nerve and lymphatics
- ureter▶️close to suspensory ligament (medial at level of bifurcation of external iliac). Avoid transection.


Which structure should surgeon ligate during histerectomy? Why?

Transverse cervical ligament (cardinal ligament)▶️uterine artery courses in its superior portion


In which structure are the serotonergic neurons?

Raphe nuclei


Most dreaded cause of isolated acute III CN palsy, and other causes.

*Actively enlarging intracranial aneurisma
- herniation of uncus
- microvascular nerve ischemia (DM)


Which is the only cranial nerve that decusates before innervates its target?

Throclear nerve IV CN


Which type of cellular junction and protein is the target in pemphigus vulgaris?

Desmosome ▶️ autoantibodies against desmoglein (cadherin)


Which type of cell junctions in renal glomerular capillary are involved in preeclampsia?

Fenestrae ▶️ swollen


Autoantibodies against integrin in hemidesmosome can result in what diseases?

Bullous pemphigoid
Pemphigoid gestationis


Target cell junctions and proteins of endotoxin of clostridium perfringens.

Thight junctions ▶️ claudins, occludins ▶️ paracellular barrier to water and solutes
❌ intestinal barrier ▶️ water loss to intestinal lumen ▶️ watery diarrhea


Territory of the leg that innervates common peroneal nerve. Clinical presentation if injury.

- superficial peroneal nerve ▶️ lateral compartment muscles of food ▶️ eversion; sensitivity of dorsum.
- deep peroneal nerve ▶️ anterior compartment muscles of food ▶️ dorsiflexion; sensitivity between 1st and 2nd digit.
- drop food, loss dorsal foot sensation


Where does the thoracic duct drain?

Left subclavian vein (near its junction with internal jugular vein)


In which vertebral level do the inferior vena cava (ICV) rise and drain blood into right atrium from which structures?

L4-L5 by joining common iliac veins (right and left)
Lower limbs, portal system, abdominal and pelvic viscera


Location, type of tissue and Innervation of internal and external hemorrhoids.

- Internal hemorrhoids: above dentate line, covered by columnar epithelial, inferior hypogastric plexus (autonomic - stretch), no pain, t° and touch.
- External hemorrhoids: below dentate line, covered by squamous epithelial, rectal inferrior nerve [pudendal nerve branch] (somatic - pain, touch, t°)


What mean a FOOSH injury, and which structures are usually involved?

"Fall onto an Outstretched dorsiflexed hand"
- Distal complications most common ▶️ scaphoid fracture, lunate dislocation, distal radius fracture.


Which structure lie anterior to the 3rd portion of duodenum?

Superior mesenteric artery


Which vessel may be responsible of bleeding when there is a peptic ulcer in posterior bulb of duodenum?

Gastroduodenal artery


Which are the anterior neural tube defects?

- Anencephaly (polyhidramnios, association mother DM I)
- Encephalocele


Which spinal level is evaluated in the brachioradialis reflex? What suggest a stronger and weaker reflex?

- C5-C6 (musculocutaneus nerve)
- Stronger than normal ▶️ upper motoneuron lesion
- Weak or absent ▶️ lower motoneuron lesion


Spinal levels evaluated by triceps reflex?



What is the Kehr sign and what can suggest?

- Shoulder referred pain secondary to peritoneal irritation
- Spleen laceration, Hemoperitoneum, Peritonitis ▶️ irritate phrenic nerve sensory fibers around diaphragm (peritoneum) ▶️ referred pain to C3-C5 shoulder region

*phrenic nerve irritation also cause hiccups


What is a orchiopexy? For what is used?

Surgical repair of undescended testicle lodged within inguinal canal ▶️ pull through the superficial inguinal ring into scrotum

Cryptorchidism ▶️ if within inguinal canal can descend spontaneusly at 6 month, if not ▶️ surgery


In physical examination how can you identify undescended testes within inguinal canal?

Feel the mass medial to the mid-inguinal point

*deep inguinal ring (entrance to inguinal canal) is superior to the mid-inguinal point ▶️ midway between anterior superior iliac spine and the pubic tubercle


Factor associated with caudal regression syndrome

Poorly controlled maternal diabetes


What can you find on neurologic and physical examination if patient has temporal occupying lesion and then uncal herniation?

- Transtentorial uncal herniation ▶️ compression of III CN exit at midbrain ▶️ ipsilateral oculomotor palsy, fixed dilated pupils (❌ PANS, SANS predominates). Advancing ▶️ 🚫 vestibular-ocular reflexes, decorticate, descerebrate position.
- ⬆️ Intracranial pressure ▶️ Cushing triad ▶️ bradypnea, HTN, bradycardia


What is the in-utero cause of midgut atresias (jejunum, ileum)? Common presentation.

- Vascular occlusion ▶️ superior mesenteric artery
- Billious emesis, specimen at distal part (jejunum) assumes spiral configuration around an ileocolic vessel ("Apple-peel")


Causes and findings in a IV CN palsy.

- Traumatic or Idiopathic: some idiopathic→Microvascular ischemia and Diabetes
- Upward deviation of eye (hypertropia), vertical diplopia (when see down and tower the nose→walk downstairs or read close). Improve deviation when tuckled the chin and head is tilted away from involved eye.


Which alteration can lead in testicle if there is an obstruction at left renal vein, and why does it happen? Clinical presentation.

- Obstruction in left renal vein (compression between superior mesenteric artery and aorta or retroperitoneal mass)→↑pressure
- Left gonadal vein (drain in left renal vein)→retrograde flow to testes and dilation of pampiniform plexus→Varices (Varicocele)
- Flank or abdominal pain, hematuria (left renal vein entrapment syndrome)


Embriological event that leads into tetralogy of Fallot

Abnormal neural crest cell migration ▶️ Anterosuperior deviation or displacement of infundibular septum

*most common cause of early childhood cyanosis


Which posture improves symptoms and signs of tetralogy of fallot?

Squatting ▶️ ⬆️ peripheral systemic vascular resistant (afterload) ▶️ ⬇️ right to left shunt


Most probably ligaments injured in a inversion of a plantar-flexed food mechanism sprain (lateral ankle sprain)

Anterior talofibular ligament

*Most strong forces can damage additional ligaments and cause instability of the join (posterior talofibular, calcaneofibular)


Part of brachial plexus commonly injured and clinical findings when head and neck are violently moved away from ipsilateral shoulder

- Upper trunk at C5-C6
- Arm medically rotated and adducted, extended and pronated ▶️ "Erb palsy"
- Sensory loss lateral aspect arm and forearm


Which nerve commonly injured in radical mastectomy with axillary lymph node removal? Clinical signs.

- Long thoracic nerve (C5-C7)→serratus anterior→stabilize and rotate scapula upward (complete abduction initiated by deltoid and supraspinatus→rotate glenoid cavity superiorly→pass arm over the head)
- Paralysis of serratus anterior→difficulty abduct arm past the horizontal position, winging of the scapula


Usual region of spinal cord involved in syringomyelia and clinical findings.

- Ventral white commissure→decussation of the fibers of lateral spinothalamic tract→pain and temperature from peripheral receptors to somatosensory cortex
- Destruction→loss pain and temperature sensation bilaterally over affected dermatomes (star at 1 or 2 levels below lesion)

*Classically disproportionate loss of pain and Tº sensation in arms and hands→dissociated anesthesia


Failure of the intrauterine process that causes cleft lip. During which week of gestation does it occur?

- Failure of fusion of the maxillary prominence and intermaxillary segment (come from medial nasal processes fusion)→primary palate formation
- 5th to 6th week


Failure of the intrauterine process that causes cleft palate. During which week of gestation does it occur?

- Failure of fusion of palatine shelves (come from maxillary prominences, and grows medially to form secondary palate) with one another or with primary palate (posterior aspect)
- 7th to 8th week


Which information carries the hypothalamospinal tract and what happen when is disrupted?

- Hypothalamus to ciliospinal center of intermediolateral cell column (T1-T2)→sympathetic innervation to ipsilateral eye and face
- Horner syndrome→ptosis, myosis, anhydrosis


Most common tendon injured in rotator cuff syndrome. Function of it.

- Supraspinosus muscle
- Abduction of humerus (pain with this movement and increase with active resistance)


Further complication of scaphoid fracture. Symptoms of fracture and mechanism which it occurs.

- Avascular necrosis and nonunion
- Tenderness in anatomical snuffbox, persistent wrist pain
- Falling on outstretched hand ▶️ direct axial compression, wrist hyperextension


Portion of urethra most likely to injury in a pelvic fracture. Signs and symptoms.

- Membranous urethra at bulbomembranous junction (part of posterior urethra) ▶️ relatively unsupported by surrounded tissues ▶️ weakest
- Full bladder sensation, high-riding boggy prostate, blood at urethral meatus


What structure is damage when patient have a comatose state, mid-positioned and fixed pupils and extended extremities? How is call that posture?

Lesion of brainstem at or below the red nucleus (midbrain tegmentum, pons) ▶️ decerebrate posturing ▶️ loss of desencending excitation to the upper limb flexors (rubrospinal tract) ▶️ predominates extensors

*Lesion to neural structures above red nucleus (cerebral hemispheres, internal capsule) ▶️ decorticate (flexor) posturing


What nerve and in which portion of its path is injury when patient present weakness extension of fingers and thum ("finger drop"), normal tricipital reflex, normal sensory function, without drop wrist? Common mechanisms of injury.

- Radial nerve when pass through supinator canal→rises the posterior interosseous nerve (from de deep branch)→finger and thumb extension
- Repetitive pronation/supination of forearm (screwdriver), direct trauma, radius subluxation


Signs and symptoms in occlusion of anterior cerebral artery

Medial portion of 2 hemispheres frontal and parietal lobes ▶️ contralateral motor and sensory deficits of leg and foots, behavioral changes (abulia), urinary incontinence (medial frontal lobe, cyngulate gyrus ▶️ micturition center)


What nerve carry the afferent limb of carotid sinus reflex? Ex, what nerve is stimulated if put a tight collar around the neck?

Carotid sinus reflex - Baroreceptor in carotid sinus:
- Afferent limb ▶️ IX CN (Hering nerve) ▶️ vagus nucleus and medullary center
- Efferent limb ▶️ X CN ▶️ hypotension, ⬇️ HR, ⬇️ cardiac contractility


Most important prognostic factor in bladder cancer. Classic clinic presentation.

- Tumor stage ▶️ degree of invasion into bladder wall and adjacent tissues ⏩ Ex, Involvement of the muscular layer
- Painless, gross hematuria

*90% ▶️ urothelial (transitional cells) carcinoma
*Squamous cell carcinoma and adenocarcinoma of bladder are rare


What is the Guyon's canal and syndrome?

- Guyon's canal ▶️ fibrooseous tunnel between hook of hamate and pisiform through ulnar nerve enters the wrist
- Ulnar neuropathy at guyon's canal ▶️ sensory loss in medial one and half digits, weakness on wrist flexion/adduction, finger abduction/adduction, flexion of 4th/5th digits. Flattened hypothenar eminence, "ulnar claw" during finger extension ▶️ weakness of lumbricals in 4th/5th digit


What portion of the intestine is almost always affected in Hirschsprung disease? why?

- Rectum
- Neural crest cells→ganglion cells (parasympathetic) of intestinal wall plexi►Meissner (submucosal) and Auberbach (myenteric)→migrate caudally (8th to 12th wk of gestation)→progress interrupted during final week of migration


What can occur if you stimulate the posterior wall of the external auditory canal? why?

- Vasovagal syncope
- Innervation by X CN→parasympathetic outflow via the vagus nerve→↓HR and BP


What structures are involved in closure of foramen ovale? How does ir occur?

After delivery▶️clamp umbilical cord, ⬇️pulmonary vascular resistance▶️⬇️right atrial pressure, ⬆️left atrial pressure▶️push againts septum primum and septum secundum▶️closes foramen ovale

*Incomplete fusion▶️Persistent foramen ovale


Embryologic process altered in DiGeorge syndrome and consequences. Genetic alteration.

*Neural crest fails to migrate to third (inferior parathyroid and thymus) and fourth (superior parathyroid) pharyngeal/branchial pouches:
- Thymic hypoplasia→T cell deficiency
- Parathyroid hypoplasia→hypocalcemia
*22q11.2 microdeletion


Signs usually found when neural crest fails to migrate to first and second pharyngeal/branchial arches.

- Hypertelorism
- Short palpebral fissures
- Micrognathia
- Bifid uvula
- Cleft palate


Structure injured in radial head subluxation (nursemaids's elbow). Mechanism of injury.

- Annular ligament
- Fall while holding hands→sharp pull hand when forearm is pronated and elbow extended


Usual mechanism of injuries of ulnar collateral ligament, and function. Treatment.

- Commonly injured in throwers (baseball pitchers)→intense valgus stress at the elbow
- Lies on medial side of elbow→strengthen ulnohumeral joint
- Reconstruction→"Tommy John" surgery


Cause of umbilical hernia

Incomplete closure of the umbilical ring→defect in linea alba→protrusion of bowel through abdominal musculature


Typical symptoms of acuda equina syndrome. Nerve roots involved.

- Compression of 2 or more of the 18 spinal nerve roots of cauda equina→low back pain radiating to one or both legs, saddle anesthesia, loss anocutaneous reflex, bowel and bladder dysfunction (S3-S5 roots), loss ankle-jerk reflex
- Massive rupture of intervertebral disk, trauma, space-occupying lesion


Typical symptoms of conus medullaris syndrome. Nerve roots involved.

- Lesions at L2→flaccid paralysis of bladder and rectum, impotence, saddle (S3-S5 roots) anesthesia. Mild weakness of the leg muscle, if lesion spare both lumbar cord and adjacent spinal and lumbar nerve roots
- Disk herniation, tumors, spinal fractures


What is the Treacher-Collins syndrome? Structures affected.

- Genetic disorder→abnormal development of 1st and 2nd pharyngeal arches
- Craneofacial abnormalities→mandibular, maxillary, zygomatic bone hypoplasia►airway commpromise, feeding difficulties
- Absent or abnormal ossicles (incus, malleus, stapes)→profound conductive hearing loss


Uses of the interscalene nerve block. Besides the intended structure to be affected, what other muscle could be paralyzed?

- Anesthetizes brachial plexus when pass scalene triangle▶️shoulder and upper arm
- Transient ipsilateral diaphragmatic paralysis▶️roots of phrenic nerve (C3-C5) when pass through interscalene sheath


Level of lesion at stem brain that lead in fixed and dilated pupils, no direct or consensual pupillary reflex

Upper midbrain→pretectal nucleus→bilateral Edinger-westphal nuclei


Level of lesion at stem brain that lead in pinpoint pupils

Bilateral pontine injury→damage of descending sympathetic fibers


Common mechanism of lesion of musculocutaneus nerve. Motor and sensitive function.

- Trauma▶️shoulder dislocation
- Strenous upper extremity activity▶️ex, baseball pitching
- Forearm flexors▶️biceps brachii, brachialis; coracobrachialis▶️flex and adduct arm
- Lateral cutaneous nerve▶️sensory lateral forearm


In which part of visual pathway a lesion can lead in Marcus gunn pupil in addition to the visual field defect?

- Optic tract lesion▶️information to the prectectal nucleus (role in pupillary reflex):
Relative afferent pupillary defect (Marcus gunn) [often optic nerve lesions - optic neuritis in MS]▶️Pupil contralateral to the tract lesion▶️nasal portion of the retina contributes more input to pretectal nucleus than temporal


Histologic features of ductal carcinoma in situ (DCIS) of breast. Common clinical presentation.

- Distended ducts by pleomorphic cells with prominent central necrosis, no beyond ductal basal membrane
- Microcalcifications in mammography, asymptomatic, normal breast examination

*Precursor of invasive ductal carcinoma▶️most common breast cancer


Optimal site for femoral nerve block

Inguinal crease at lateral border of femoral artery▶️anesthetize skin and muscles of anterior thigh (cuadriceps), femur and knee


Principal derivatives of ventral and dorsal pancreatic ducts? What is the pancreas divisum and its importance?

- Dorsal pancreatic bud▶️tail, body, head, accesory duct (of santorini)
- Ventral pancreatic bud▶️uncinate process, proximal portion of main pancreatic duct (wirsung)
- Pancreas divisum▶️failure to ventral and dorsal pancreatic duct to fuse▶️2 pancreatic drainage at different sites at duodenum (accesory have the majority)


What suggest a left vertebral artery retrograde (caudal) flow instead of normal antegrade flow?. Symptoms.

- Subclavian steal syndrome▶️Occlusion of left subclavian artery proximal to the origin of vertebral artery
- Arm ischemia in affected extremity▶️pain, exercise induced fatigue, paresthesias
- Vertebrobasilar insuffiency▶️dizziness, vertigo, drop attacks


What vessels you may injury if rectus abdominis is horizontally transacted?

Inferior epigastric artery (no supporting posterior sheath below arcuate line)▶️trauma▶️significant hemorrhage


Portion of the intestine that relay between aorta and superior mesenteric artery. Condition associated with this relationship.

Transverse portion of the duodenum▶️partial small bowel obstruction if angle between 2 vessels is less than 20 degrees (normally at least 45 degrees)⏩superior mesenteric artery syndrome

*Cause▶️⬇️mesenteric fat▶️low body weight, weight loss, etc; pronounced lordosis; surgical correction of lordosis


Classic signs of common peroneal nerve injury. Mechanism of injury.

- "Drop foot", "Steppage gait"
- Blunt trauma lateral aspect of leg, near head of fibula, fibulae neck fractures, external pressures due to prolong immobility (hospitalization)


Most common structure injured by anterior and posterior knee dislocation. Other structures involved in knee injury.

- Popliteal artery
- Tibial nerve▶️superficial of popliteal artery, injured by penetrating trauma into popliteal fossa.
- Common peroneal nerve▶️blunt traum to the lateral knee


What are the possible origins of AV nodal artery and what does it depend on?

Origin depends of coronary dominance→based on coronary artery that supplies blood to posterior descending artery (PDA)
- Right coronary artery→70%►Right dominant
- Left circumflex artery→10%►Left dominant
- Both→20%►Codominant→RCA supplies AV nodal artery

*Dominant artery supplies PDA and AV nodal artery


How can be the prostatic plexus be injured? what is the consequence and why?

- Prostatectomy→prostatic plexus lies whithin fascia of the prostate
- Give rise lesser and greater cavernous nerves→post-ganglionic parasympathetic fibers for erection→corpora cavernosa and urethra►Erectile dysfunction


What nerve are you testing when elicit cremasteric reflex? In what cases could cremasteric reflex be absent?

- Genitofemoral nerve (from L1-L2 spinal nerves)
- Testicular torsion or L1-L2 spinal injury


Which are the two main anastomoses between inferior mesenteric artery and superior mesenteric artery? Implication in situations as abdominal aortic aneurysm repair.

- Marginal artery of Drummond▶️principal anastomoses
- Arc of Riolan (mesenteric meandering artery)▶️inconsistent
- Inferior mesenteric artery is ligate and not always reconected because marginal artery


Embriologic process that failed in Meckel diverticulum. Most common clinical manifestation and complication.

- Failed obliteration of the vitelline (omphalomesenteric) duct
- Spontaneus, painless lower gastrointestinal bleeding
- Potential lead point to intussusception▶️colicky abdominal pain, "currant jelly" stools


Why can you diagnose Meckel diverticulum with 99-Tc pertechnetate scan (scintigraphy)?

99-Tc pertechnetate (radioisotope) behave as halide ion (chloride, iodine)▶️affinity for parietal cells of gastric mucosa (including ectopic)▶️⬆️uptake periumbilical or right lower quadrant typical of Meckel diverticulum


Which are the embryologic origin of females and male genital internal structures?

- Paramesonephric (Müllerian) ducts→female internal structures►fallopian tubes, uterus, upper portion of vagina (lower portion from urogenital sinus)
- Mesonephric (Wolffian) ducts→ male internal structures (except prostate)►Seminal vesicles, Epididymis, Ejaculatory duct, Ductus deferens (SEED)


What is the most common rotator fuff structures affected in rotator cuff syndrome? How do you assess it?

- Supraspinatus tendon
- "Empty-can" supraspinatus test→abduction of the humerus in parallel to the axis of the scapula (30 degrees forward flexion) while in full internal rotation (thumb pointed to the floor)


Rotator cuff structures

Tendons of supraspinatus, infraspinatus, teres minor, subscapularis (SITS)→stability and motion of the glenohumeral joint


Embriologic abnormality that cause pancreatic tissue encircling the duodenum, how does it call? Clinical presentation.

- Annular pancreas→abnormal migration of the ventral pancreatic bud to fuse with the dorsal bud at 7th and 8th wk
- Usually asymptomatic, duodenal obstruction or pancreatitis


Most common site of blunt aortic injury (traumatic aortic rupture) and why? Typical mechanism of injury.

- Aortic isthmus→tethered by the ligamentum arteriosum, relatevely fixed and immobile
- Sudden deceleration (motor vehicle collisions)


Which neurotransmitter produce pigmented neurons in the posterior rostral pons at the lateral floor of the fourth ventricle? What is that region?

Locus ceruleus→Norepinephrine


Function of locus ceruleus. Cosequence of abnormal activation.

- Control of mood, arousal (reticular activating system), sleep-wake states, cognition, autonomic function (blood pressure)
- Anxiety disorders (ex, panic attacks)


Which coronary artery supplies the inferior surface of the heart?

Right coronary artery→posterior descending artery (70-80%, right dominance)

*Inferior surface→left ventricle (2/3), right ventricle (1/3)


During postpartum hemorrhage due uterine atony that does not respond to uterine massage and uterotonic medications, what structure may you ligate to stop the bleeding and preserve fertility and why?

- Internal iliac arteries→uterine arteries►major blood supply of uterus
- Uterus has collateral blood flow from ovarian arteries

*Other structures supplied by internal iliac arteries have collateral circulation as well


What process have failed in a primum type atrial septal defect?

Failure of the septum primum to fuse completely with the endocardial cushions→persistent ostium primum


Which embryologic structures give rise to the arteries that contribute to the blood vessels that supply the brain?

- 3rd Aortic arch→Common Carotid artery and proximal part of internal Carotid artery►middle and anterior cerebral arteries→anterior circulation of circle of Willis
- 4th Aortic arch→On left, aortic arch; on right, proximal part of right subclavian artery►origin of both vertebral arteries→posterior circulation of circle of Willis


Within true pelvis ureter is immediately anterior to which structure?

Anterior to internal iliac artery and medial to the ovarian vessels (female)


Midway from the kidney to pelvic inlet how is the relationship between gonadal vessels and ureter?

Gonadal artery and vein cross over the anterior surface of the ureter (ureter is posterior to them)


Within the true pelvis how is the relationship between gonadal vessels and ureter?

- Females→both enter true pelvis, ureter course medial to gonadal vessels (ovarian vessels)
- Males→Testicular vessels NO enter to true pelvis, course around pelvic brim→deep ring of the inguinal canal


Which hole is crossed by III CN to enter to the orbit? What other structures also cross that hole?

Superior orbital fissure: III, V1 (sensory limb of the corneal reflex - motor is VII temporal branch), IV, VI, superior ophtalmic vein


Boundaries of carpal tunnel, importance of them in surgical treatment of carpal tunnel syndrome.

- Dorsal surface→carpal bones
- Palmar surface→transverse carpal ligament (flexor retinaculum)►incision during Cx improve symptoms of carpal tunnel syndrome


Which structure occupies most of the volume of the greater sciatic foramen? Clinical importance of it.

Piriformis muscle→injury or hypertrophy→compress sciatic nerve►sciatica-like symptoms (piriformis syndrome)

*Above piriformis→superior gluteal vessels and nerve
*Below piriformis→inferior gluteal vessels, internal pudendal vessels, sciatic nerve


Which nerve is deep to the mucosa overlying the piriform recess? what function does it accomplish?

- Internal branch of superior laryngeal nerve (branch from X CN)→only sensory and autonomic fibers
- Affetent limb of cough reflex→sensation from the mucosa superior to the vocal cords

*Foreign bodies can become logged in piriform recess→direct damage to the nerve or in attempt to retrieve it


In which portion of the brain stem could be the lesion in a right internuclear ophtalmoplegia?

*Typical causes of the lesion.

Pons→lesion at left medial longitudinal fasciculus (MLF)►communication between CN III and CN VI nuclei→conjugate horizontal gaze
- Impaired adduction of the ipsilateral (left in this case) eye during right conjugate horizontal gaze

*Lacunar stroke in pontine artery (unilateral). Multiple sclerosis (bilateral).


What clinical presentation may result from lesion at superior colliculus and why?

- Superior colliculus→control vertical gaze
- Lesion at dorsal midbrain→Parinaud syndrome►upward gaze palsy, absent pupullary light reflex, impaired convergence


Clinical findings in internuclear ophtalmoplegia

Disorder of conjugate horizontal gaze→affected eye (ipsilateral to the lesion) cannot adduct, contralateral eye abducts
- Diplopia, nystagmus of the abducting eye
- Convergence and pupillary light reflex preserved


Which nerve could be damaged during appendectomy and the symptoms?

- Iliohypogastric nerve→sensation of the suprapubic (anterior branch) and gluteal (lateral branch) regions, muscles of anterolateral abdominal wall
- Damaged anterior branch→↓sensation and/or burning pain at suprapubic region


Cause of bilateral or unilateral renal agenesis. Which syndrome can be associated in utero?

- Failure developing ureteric buds (ureters, renal pelvis, calyces, collecting ducts)→interaction with metanephric vesicles (mesenchyma)→(+) formation of glomerulus through distal convoluted tubule (Nephron)
- Potter sequence


Which is a unique feature of spleen respect to its embriology?

Derivative from mesoderm of dorsal mesentery and recieve blood supply from foregut derivative (splenic artery off the celiac trunk)

*Spleen is not a foregut derivative


Which vitamins may be increased secondary to a gastric bypass surgery for morbid obesity (Roux-en-Y)? Other symptoms associated.

Small intestinal bacterial overgrowth (SIBO)→larger bypassed portion of stomach and duodenum are reattachedto the jejunum distally→bacteria proliferate►↑Vitamin K, Folate, ferment food (nausea, bloating, abdominal disconfort, malabsorption)

*Deficiency due malabsorption→Vitamins B12, A, D, E, also Zn, Fe


Proximal and distal blood supply of ureter

- Proximal→Renal artery branches
- Distal→Superior vesical artery branchies
- In between→variable, anastomotic→branches of gonadal, common and internal iliac, aorta, uterine arteries


In a Liver trauma and bleeding, occlusion of which structure allow to differentiate the source of vascular damage and how is call that maneuver? Compounds of that structure.

- Hepatoduodenal ligament→Portal triad►Portal vein, hepatic artery and common bile duct
- Pringle maneuver→if bleeding doesn't stop►probably source is inferior vena cava or hepatic veins


Which structures carry the most oxygenated blood in fetal circulation?

Umbilical vein→ductus venosus►Inferior vena cava


Origin of umbilical arteries

Fetal Internal iliac arteries


Where is the Wernicke's area? Blood supply. In which case Wernicke's aphasia develops?

- Posterior part of the superior temporal gyrus
- Middle cerebral artery
- Lesion at dominant hemisphere


Presentation of lesion at arcuate fasciculus. Function.

- Connect Wernicke's area with Broca's area
- Conduction aphasia→striking inability to repeat. Language comprehension and output are preserved.


Location of Broca's area

Inferior frontal gyrus


What is the cause of hematocolpos? Symptoms and signs

- Imperforate imen
- Primary amenorrhea, normal secondary characteristics development, cyclic abdominal or pelvic pain (accumulation fo menstrual blood in vagina or uterus), back pain and constipation
- Vaginal bulge, mass anterior to he rectum


Type of communication between osteocytes

Gap junctions→exchange nutrients and waste products


Within retroperitoneum which are the vascular structures related with ureters?

Ureters pass posterior of the ovarian (gonadal) vessels and anterior to the common/external iliac artery to reach true pelvis


Where is the source of anterior bleeding of nose?

Kiesselbach plexus at nasal septum→anastomosis of anterior ethmoidal artery, sphenopalatine artery, superior labial artery

*Posterolateral branches of sphenopalatine artery is the source of posterior bleedings→severe, no tx with cautery


Which embryonic germ layer is the origin of the cells that fill the lumen of the esophagus in the esophageal atresia?. Pathological Findings.

- Endoderm
- Fibrotic esophagus with no lumen


What are the slit-like openings visualized near the lateral ends of the top of the trigone of the bladder?

Ureteric orificies (ureteral meatus)→ opening of a ureter into the urinary bladder at one corner of the trigone of the bladder