Transcript File

Applied Anatomy of Abdomen
Abdomen, Pelvis & Perineum Unit
Lecture 10
‫ حيدر جليل األعسم‬.‫د‬
Lecture 1: Anterior Abdominal wall
Surgical Incisions
• Along lines of cleavage?
Location depends on: type of operation, location of organ(s), bony or
cartilaginous boundaries, avoidance of (especially motor) nerves,
maintenance of blood supply, and minimizing injury to muscles & fascia.
A. Longitudinal Incisions:
1. Median or midline incision: through linea alba above/below
umbilicus
2. Paramedian incisions: longitudinal incisions para-sagittal plane.
3. Pararectus incisions: along lateral border of rectus sheath.
undesirable?
4. Abdominothoracic incision for lower end of esophagus.
B. Oblique and Transverse Incisions:
1. Gridiron (muscle-splitting) incisions used for an appendectomy.
McBurney incision is made at McBurney point? less popular?
2. Suprapubic (Pfannenstiel) incisions (bikini incisions) at pubic hairline
for cesarean section and most gynecological and obstetrical operations.
3. Subcostal incisions for gallbladder & biliary ducts (right side) and for
spleen (left side). It is parallel & inferior to costal margin?
4. Inguinal incisions for repairing hernias may injure ilioinguinal nerve.
Lecture 1: Anterior Abdominal wall
Paracentesis of the Abdomen:
It is withdrawal of excessive collections of peritoneal fluid, as in ascites.
A needle or catheter is inserted through anterior abdominal wall. If a
needle is inserted in the flank, it will pass through the following:
(1) skin,
(2) superficial fascia,
(3) deep fascia,
(4) aponeurosis of external oblique,
(5) internal oblique muscle,
(6) transversus abdominis muscle,
(7) fascia transversalis,
(8) extraperitoneal fatty tissue
(9) parietal peritoneum.
Lecture 1: Anterior Abdominal wall
Collateral Pathways of Superficial Abdominal Veins
When flow in inferior vena cava is
obstructed, anastomoses between
tributaries of superior & inferior vena
cavae , such as thoracoepigastric vein,
may provide collateral pathways by which
obstruction may be bypassed, allowing
blood to return to the heart. Small
cutaneous (systemic) veins surrounding
umbilicus also anastomose with the
paraumbilical veins (tributaries of
portal vein), which run with obliterated
umbilical vein (round ligament of liver).
During either caval or portal obstruction,
anastomosing veins may also become
distended, causing caput medusae
appearance.
Lecture 2: Inguinal Canal & Scrotum
Varicocele
A varicocele is a condition in
which the veins of the
pampiniform plexus are
elongated and dilated. It is a
common disorder in
adolescents and young adults,
with most occurring on the
left side. This is thought to be
because the right testicular
vein joins the low-pressure
inferior vena cava, whereas
the left vein joins the left
renal vein, in which the
venous pressure is higher.
Lecture 3: Posterior Abdominal Wall
Psoas Abscess and Tuberculosis
Psoas fascia covers anterior surface of psoas muscle and can influence
direction taken by a tuberculous abscess. TB of thoracolumbar
vertebrae results in destruction of vertebral bodies, with possible
extension of pus laterally under psoas fascia. From there, pus tracks
downward, following course of psoas muscle, and appears as a swelling
in upper part of thigh below inguinal ligament. It may be mistaken for a
femoral hernia.
Lecture 5: Esophagus, Stomach & Duodenum
Hiatus Hernia
A hiatus hernia is a protrusion of a part of stomach into mediastinum
through esophageal hiatus of diaphragm. Hernias occur most often in
people after middle age, possibly because of weakening of muscular
part of diaphragm and widening of esophageal hiatus. Two types are:
Paraesophageal hiatal hernia: less common, cardia remains in its
normal position. However, a part of fundus extends through esophageal
hiatus anterior to the esophagus.
Sliding hiatal hernia: abdominal part of esophagus, cardia, and parts of
fundus of stomach slide superiorly through esophageal hiatus to thorax.
Lecture 5: Esophagus, Stomach & Duodenum
Vagotomy:
It is surgical section of the vagus nerves because secretion of acid is
largely controlled by vagus nerves.
A. Truncal vagotomy: (surgical section of vagal trunks) is rarely
performed because innervation of other abdominal structures is also
sacrificed.
B. Selective gastric vagotomy:stomach is denervated but vagal branches
to pylorus, liver & biliary ducts, intestines & celiac plexus are preserved.
C. Highly selective vagotomy: attempts to denervate only area in which
parietal cells are located, sparing other gastric function (motility)
stimulated by vagus nerve.
Lecture 6: Small & Large Intestine
Visceral Referred Pain: There are two types of pain:
A. Somatic pain (sharp and localized easily) arises from organs such as
muscles, bones & parietal peritoneum.
B. Visceral pain (dull and poorly localized) arises from an organ such as
stomach and intestine.
C. Referred pain (dull and localized) is a visceral pain arising from viscera
but felt (radiate) to dermatome level, which receives visceral fibers from
organ concerned.
Lecture 6: Small & Large Intestine
Appendicitis
Is acute inflammation of the appendix is caused by occlusion of lumen
either in young people by hyperplasia of lymphatic follicles in appendix
Or in older people, obstruction results from
a fecolith that forms around a center of fecal
matter. When secretions from appendix
cannot escape, appendix swells, stretching
visceral peritoneum. Visceral pain of
appendicitis, therefore, referred to
periumbilical region because afferent
pain fibers enter spinal cord at T10 level.
Later, severe pain in right lower quadrant
results from irritation of parietal
peritoneum lining abdominal wall
(Shifting Pain).
Lecture 8: Liver, Spleen and Pancreas
Gallstones
A gallstone is a concretion composed chiefly of cholesterol crystals in
biliary system. They may cause injury to gallbladder or obstruction of
biliary tract. Distal end of hepatopancreatic ampulla is narrowest part
of biliary passages and is a common site for
impaction of gallstones. Hartmann pouch
(infundibulum of gallbladder) is a dilation at
junction of neck of gallbladder and cystic duct
and is another common site for impaction.
Gallstones lodged in cystic duct causes
biliary colic (intense, spasmodic pain). If stone
blocks cystic duct, cholecystitis (inflammation of
gallbladder) occurs because of bile accumulation
& enlargement of gallbladder.
Acute Cholecystitis is inflammation of
gallbladder which may cause irritation of
subdiaphragmatic parietal peritoneum,
which is supplied in part by phrenic nerve. This
may give rise to referred pain over right shoulder.
Lecture 8: Liver, Spleen and Pancreas
Gallstones in the Duodenum
Dilated and inflamed gall bladder owing to an impacted gallstone in its
duct, may develop adhesions with adjacent viscera. Continued
inflammation may break down (ulcerate) tissue boundaries between
gallbladder and a part of alimentary tract adherent to it, resulting in a
cholecystenteric fistula.
Because of their proximity to
gallbladder, the superior part of
duodenum and transverse colon
are most likely to develop a
fistula of this type. The fistula
would enable a large gallstone,
incapable of passing though the
cystic duct, to enter the
alimentary tract that may become
trapped at the ileocecal valve,
producing a bowel obstruction
(gallstone ileus).
Lecture 8: Liver, Spleen and Pancreas
Pancreatic Head Cancer
Cancer of the head often compresses and obstructs the bile duct and/or
the hepatopancreatic ampulla. This condition causes obstruction,
resulting in the retention of bile pigments, enlargement of the
gallbladder, and jaundice (obstructive jaundice). Cancer of the neck and
body of the pancreas may cause portal or inferior vena caval obstruction
because the pancreas overlies these large veins.
Lecture 9: Kidney & Ureter
Renal and Ureteric Calculi
Calculi may form and become located
in calices of kidneys, ureters, or
urinary bladder. A renal calculus
(kidney stone) may pass from kidney
into renal pelvis and then into ureter.
If stone is sharp, or it is larger than
normal lumen of ureter (about 3 mm)
causing excessive distension of this
muscular tube, ureteric calculus will
cause severe intermittent pain
(ureteric colic) as it is gradually forced
down the ureter by waves of
contraction. Calculus may cause
complete or intermittent obstruction
of urinary flow. Depending on level of
obstruction, pain may be referred to
the lumbar or inguinal regions, or the
external genitalia and/or testis.
Lecture 9: Kidney & Ureter
Pelvic Kidney (ectopic kidney)
Kidney may be arrested in some part of its normal embryonic ascent; it
usually is found at the brim of pelvis.
Horseshoe Kidney
Caudal ends of both kidneys fuse as they develop resulting in horseshoe
kidney. Both kidneys start to ascend from pelvis, but the interconnecting
bridge becomes trapped behind inferior mesenteric artery, so kidneys
come to rest in low lumbar region. Both ureters are kinked as they pass
inferiorly over the bridge of renal tissue, producing urinary stasis, which
may result in infection and stone formation.
Thank You