Week 1 Flashcards
Bones that make up the hemi-pelvis
pubis, ilium & ischium
Divisions of the pelvis
- greater and lesser pelvis
What structure divides the pelvis
pelvic inlet
difference between child and adult pelvis
- cartilage in child pelvis
- after puberty the bones fuse
- triradiate cartilage
anatomical orientation of the human pelvis
- ant
- median
- ASIS and anterior pubic symphysis lie in same vertical plane
- coccyx appears close to the center of the pelvic inlet
- sacral promontory is located directly superior to the center of the pelvic outlet
What is the greater pelvis
- bounded by
- what lies within
- other name
- superior to pelvic inlet, bounded by iliac alae posterolaterally & anterosuperior S1 vertebra posteriorly
- abdominal viscera
- false
What is the lesser pelvis
- bounded by
- what lies within
- other name
- between pelvic inlet & outlet, bounded by pelvic surfaces of hip bones, sacrum & coccyx
- reproductive organs, bladder
- true pelvic cavity
boundaries of pelvic inlet
- Posterior
- Lateral
- Anterior
- Posterior: promontory & ala of sacrum;
- Lateral: R & L linea terminalis (arcuate line, pecten pubis & pubic crest);
- Anterior: pubic symphysis
boundaries of pelvic outlet
- Anterior
- Lateral
- Posterior
- Posterolateral
- Anterior: pubic arch;
- Lateral: ischial tuberosities;
- Posterior: tip of coccyx;
- Posterolateral: inferior margin of sacrotuberous ligament (runs between coccyx & ischial tuberosity)
3 functional roles of pelvis
Bear/transfer weight, provide attachment for mm. & reproduction
Sex differences in the Pelvis
- general structure
- greater pelvis
- lesser pelvis
- pelvic inlet
- pelvic outlet
- pubic arch and suprapubic angle
- obturator foramen
- acetabulum
- greater sciatic notch
- suprapubic angle
- M: thick and heavy, W: thin and light
- M: deep, W: shallow
- M: narrow and deep, W: wide and shallow
- M: heart shaped, narrow, W: oval and rounded, wide
- M: small, W: large
- M: narrow, W: wide
- M: <70 degrees, W: >80 degrees
- M: round, W: oval
- M:~70 degrees, W: 90 degrees
- M: narrow, W: wide
Obstetric conjugate
- what does it measure
- why is it important
- can it be truly measured?
○ minimum AP diameter of lesser/true pelvis; goes from middle of sacral promontory to posterosuperior margin of pubic symphysis
○ narrowest fixed distance through which baby’s head must pass in vaginal delivery
- cannot be measured directly d/t bladder
Diagonal conjugate
- how is it measured
○ measured by palpating sacral promontory with tip of middle finger
○ use other hand to mark level of inferior margin of pubic symphysis of examining hand
Importance of conjugates in partuition
○ if ischial tuberosities are far enough apart to permit 3 fingers to enter vagina side by side, subpubic angle considered sufficiently wide to permit passage of average fetal head at full term
What is narrowest mediolateral diameter in pelvic outlet
○ Interspinous distance (between ischial tuberosities)
If ischial tuberosities allow for 3 fingers to enter vagina side by side, subpubic angle is sufficiently wide to permit passage of an average fetal head at full term
How would you measure pelvic outlet during PE to ensure it is large enough for baby’s head to pass
○ Diagonal conjugate: palpate the sacral promontory with the tip of the middle finger, using the other hand to mark the level of the inferior margin of the pubic symphysis on the examining hand. After the hand is withdrawn, the distance between the tip of the index finger & the marked level of the pubic symphysis is measured to estimate the true conjugate (should be > 11cm)
Components of the diencephalon
Epithalamus, thalamus, hypothalamus, & subthalamus
what structure lies between the halves of the diencephalon
Third ventricle
structure that separate the thalamus dorsally and the hypothalamus and subthalamus inferiorly
Hypothalamic sulcus: small groove on lateral wall of 3rd ventricle
major lobes of the pit gland
Anterior & posterior
Describe the principal functions reg by pit gland
Production of hypophysiotropic hormones that control secretion of anterior pituitary hormones
blood supply to pit gland
Internal carotid aa. → superior & inferior hypophyseal branches
- superior hypophyseal arteriessupply median eminence and infundibular stalk
- inferior hypophyseal arteriesprovide blood mainly for neurohypophysis
what hormones are released by the post pit
AVP (aka ADH or Vasopressin) & Oxytocin
what hormones are released by the ant pit
- Prolactin, LH/FSH, TSH, GH, ACTH
epithalamus
- what strx make this up?
- what strx attaches the pineal gland to posterior commisure
- describe the primary function of the pineal gland
- Habenular trigones on each side of the 3rd ventricle, pineal body & habenular commissure
- ventral lamina of the stalk
- secrete melatonin
describe the relationship between the pineal gland and reg of hormones released from pit gland
- pineal gland makes melatonin -> regulates bodys internal sleep-wake cycle -> influences hormone secretion from hypothalamus -> hypothalamus secretes releasing hormones -> pituitary gland secretes other hormones
Adrenal Glands
- are adrenal glands intra or retroperitoneal?
- attachment of adrenal gland, importance?
- function of 2 parts of adrenal
- retroperitoneal; never suspended on mesentery, develop association with body wall, parietal peritoneum on organ surface
- Enclosed by renal fascia & attached to crura of diaphragm, Kidney can be removed from a donor without damaging the suprarenal gland because of the weak septum of renal fascia that separates the 2
- Cortex: secretes corticosteroids & androgens
Medulla: mass of nervous tissue associated with SNS (chromaffin cells secrete catecholamines (epi & norepi))
Vasculature of adrenal glands
- arteries
- veins
○ Inferior phrenic aa. → Superior suprarenal aa.
○ Abdominal aorta → Middle suprarenal aa.
○ Renal aa. → Inferior suprarenal aa.
○ R suprarenal v. → IVC
L suprarenal v. → L renal v.
innervation of the adrenal glands
–Sympathetic innervation (T5-T8/9)
Lateral horn -> Ventral horn -> Ventral rootlets -> Ventral root (Ventral rami) -> Spinal nerve -> Anterior 1⁰ rami -> White communicans rami -> sympathetic chain ganglion -> greater splanchnic nerve -> celiac ganglion -> celiac plexus -> chromaffin cells of suprarenal gland (SYNAPSE)
–Vasculature
Lateral horn -> Ventral horn -> Ventral rootlets -> Ventral rami -> Spinal nerve -> Anterior 1⁰ rami -> White communicans rami -> sympathetic chain ganglion -> greater splanchnic nerve -> celiac ganglion (SYNAPSE) -> celiac plexus -> vasculature
Compare and contrast the ant pit images, what are the differences?
- Left: normal pit, there are several distinct cell populations containing a variety of stimulating hormones
- right: pituitary adenoma, monomorphism of these cells with absence of reticular network
What is?
- adenoma
- microadenoma
- macroadenoma
○ Adenoma: normally benign, classified on basis of hormones that are produced by neoplastic cells, detected by IHC
○ Microadenoma: <1 cm diameter
- Macroadenoma: >1 cm diameter
Discuss some potential clinical findings that might be associated with macroadenoma.
○ Neurologic (visual, HA), pituitary hypofunction due to compression
- Nonfunctional adenomas likely to come to clinical attention at later stage than those a/w endocrine abnormalities and are therefore more likely to be macroadenomas
Explain why some tumors present when they are small & others do not present until they are large.
○ Functional hormone-secreting tumors or tumors having immediate mass effect on another structure often present when small
- Functioning adenomas (microadenomas) are a/w distinct endocrine signs and symptoms, while nonfunctioning (silent) adenomas (macroadenomas) typically present with mass effects, including visual disturbances
Diagram the g-protein receptor pathway
- g protein signaling in endocrine neoplasia
- G proteins (composed of α and βγ subunits) play a critical role in signal transduction, transmitting signals from cell surface receptors (GHRH, TSH, or PTH receptor) to intracellular effectors (e.g., adenyl cyclase), which then generate second messengers (cAMP, cyclic adenosine monophosphate) that stimulate cellular responses.
- Mutations that lead to G-protein hyperactivity are seen in a variety of endocrine neoplasms, including pituitary, thyroid, and parathyroid adenomas.
Pituitary adenoma non-functioning vs functioning
- Presenting features
- Gross pathology
- Micro pathology
- NF: Radiographic abnormalities of sella turcica, visual field abnormalities, S&S of elevated intracranial pressure, hypopituitarism; F: Depends on type: lactotroph, gonadotroph and somatotroph
- NF: Larger lesions usually extend superiorly through the diaphragm sella into the suprasellar region, where they compress the optic chiasm & adjacent structures (CN), Foci of hemorrhage & necrosis; F: Smaller, gelatinous, soft, well-circumscribed, confined to sella turcica, anterior to clinoid processes
- NF: Cellular monomorphism, absence of a significant reticulin network, Uniform, polygonal cells in sheets or cords, sparse mitotic activity; F: Similar
3 zones of adrenal cortex and hormones the produce
Glomerulosa– Mineral corticoids (aldosterone)
Fasiculata - Glucocorticoids
Reticularis - “sex” androgens
Discuss main pathophysiological changes in patients due to hyperplasia or hypoplasia/atrophy of the adrenal cortex.
○ Hyperplasia: Cushing, CAH (congenital adrenal hyperplasia)
○ Hypoplasia: Addison, loss of glucocorticoids, mineralocorticoids, or androgens
Medulla
- cells that make it up
- what do they resemble?
- histo
- what do they secrete?
- chromafin cells
- sympathetic neuron
- large pale-staining cells, arranged in cords interspersed with wide capillaries. Faintly stained cytoplasmic granules can be seen in most chromaffin cells
- nor epi and epi
Adrenocortical adenoma
- Is it possible to predict the functional status of neoplasm based on its gross or microscopic appearance?
- Describe the morphologic features of adrenocortical adenoma.
- How does the cortex adjacent to nonfunctional adenomas differ from the cortex adjacent to functional adenomas?
- No, cannot be distinguished on the basis of morphologic features; functionality is based on clinical evaluation, and measurement of hormones or hormone metabolites in the blood
- Well-circumscribed, nodular lesion, up to 2.5cm, yellow-brown (lipids), expands adrenal medulla
- Functional: atrophy; Nonfunction: normal
Histo to differentiate adrencortical carcinoma from adenoma
- Carcinoma (A): big nucleolus, increased nucleus to cytoplasm, monstrous cells
- Adenoma (B): nuclei happy
In general, in the adrenal cortex, when you have a significant amount of anaplasia, that is cancer - They can both secrete or not secrete
What is the most common cause of Cushing’s
Pituitary adenoma
CA in medulla
- rule of 10
- cant tell if benign or malignant with histo, only if there are mets
- 10% are: malignant, bilateral, do not secrete, kids, extra-adrenal, calcify
Pheochromocytoma
rare tumor of adrenal gland tissue. It results in the release of too much epinephrine and norepinephrine, hormones that control heart rate, metabolism, and blood pressure
Hypothalamic nuclei
- what is parvocellular neuron
- what do they secrete to where?
- what is magnocellular neuron and where are they?
- what do magnocellular neuron cells secrete
- Small, project into median eminence
- CRH, TRH to anterior pituitary
- Larger, unmyelinated axons form hypothalamo-hypophyseal tract
- Paraventricular (oxytocin) & supraoptic nuclei (ADH) of hypothalamus
- OT, AVP to posterior pituitary
Pituitary Structure
- location
- 3 parts of the anterior pituitary gland
- What is the basic function of the pars nervosa?
- alternate names of pars nervosa
- basic function of the pars distalis
- alternate names of pars distalis
- What is the hypothalamic-hypophyseal portal system
- Hypothalamic-hypophyseal portal system
- Hypothalamic-hypophyseal tract
- Located in sella turcica of the sphenoid bone, inferior to hypothalamus
- Pars distalis: basophils (10%), acidophils (40%), chromophobes (50%); Pars intermedia: basophils: MSH stimulates pigment in melanocytes; chromophobes: ACTH & LPH; Pars tuberalis: wraps around infundibulum, mostly gonadotrophs
- Storage & releasing site for ADH & oxytocin
- Neurohypophysis or posterior pituitary
- Secrete somatotrophs (GH), thyrotrophs (TSH), gonadotrophs (LH &FSH)
- Adenohypophysis or anterior pituitary
- Superior & inferior hypophyseal aa.; consists of 3 capillary networks connected by the hypophyseal portal v.
- axons extending from the hypothalamic supraoptic & paraventricular nuclei, through the infundibulum & into the pars nervosa of the posterior pituitary, where peptide hormones are released for capillary uptake
Pars Nervosa
- what is it
- What are pituicytes?
- What are Herring bodies, & what is their function?
- What is neurophysin?
- Neuro 1 and 2
○ Posterior pituitary: modified neural tissue containing unmyelinated axons
○ Unsheathed glial cells, support unmyelinated axons
○ Swellings of PVN & SON from which oxytocin or vasopressin is stored
○ Neuropeptide, Released with oxytocin & ADH, helps them get to site of action–transport/carrier proteins within axon and storage proteins within Herring bodies
○ neurophysin 1 = oxytocin
○ neurophysin 2 = 2 ADH
What is central DI
Central diabetes insipidus: decreased secretion of ADH, causes polyuria & polydipsia (decreased UA osmolality)
Pars Distalis Epi
- How do Chromophobes stain? What do they do?
- How do Acidophils stain? What do they secrete?
- difference between acidophils and RBC
- How do Basophils stain? What do they secrete?
- What kind of endothelium makes up blood vessel wall?
- How about IHC?
- Weakly stain, degranulated chromophils, inactive reserve cells or undifferentiated stem cells
- Stain red, secrete GH (somatotrophs) or prolactin (lactotrophs) (PiG)
- look for nucleus to differentiate b/w RBC and fenestrated capillaries
- Stain purple, secrete corticotrophs, gonadotrophs, & thyrotrophs (FLAT)
• Fenestrated capillaries - Can do it based off of the hormones
Pars Distalis Epi electron microscopy
- somatotrophs
- thyrotrophs
- corticotrophs
- gonadotrophs
- packed with secretory granules of moderate size
- have smaller granules than somatotrophs
- have sparse secretory granules which are located at the periphery of the cell
- secretory grnaules are relatively small
Pineal Gland
- What does pineal mean?
- Where is it located?
- What portion of the ANS innervates the pineal gland?
- What is a pinealocyte? What does it secrete?
• What other cell type is here?
• What are the dark areas called?
- Pea-sized conical mass of tissue (aka epiphysis cerebri)
- Behind 3rd ventricle, attached to brain by short stalk
- SNS from superior cervical ganglion. PSNS from pterygopalatine & Otic ganglia
- Secretory cell, secretes melatonin
- Corpora arenacea (brain sand): concentrations of Ca & Mg, increases with age
- Interstitial glial cells (modified astrocytes)
