Ultrasound can be used to evaluate different types of hernias in the groin and abdominal wall. Indirect inguinal hernias originate lateral to the inferior epigastric artery, while direct inguinal hernias occur medial to the artery. Spigelian hernias occur where the transverse abdominis and internal oblique muscles are torn near the inferior epigastric vessels. Femoral hernias arise in the femoral canal below the inguinal ligament. Linea alba hernias protrude through the midline fascia. Umbilical hernias occur through a widened umbilical ring. Incisional hernias develop through surgical scars. Hern

1. ULTRASOUND OFHERNIAS
Presented by: Syed Muhammad Yousaf Farooq

2. SONOGRAPHYOF INGUINALREGIONHERNIAS
ANATOMY
Theinguinalligament, the folded and
thickened lower border of the
external oblique aponeurosis, attaches
at the anterior superior iliac spineand
pubictubercle and medially forms the
inferior floorof the inguinalcanal.
Thedeep inguinal ring isan anatomic
defect in thetransversalis fascia.
Thesuperficial inguinal ring isa
triangle-shapedanatomic defect in the
external oblique aponeurosis
immediately superior andlateralto the
pubictubercle.

3. Theinferior epigastric artery
originates from the externaliliac
artery proximal to the inguinal
ligament, initially passingalong
the medial boundary of thedeep
inguinal ring, andascends
obliquely andmedially to the
rectus abdominismuscle.
When the posteriorabdominal
wall isviewed fromwithin---
Hesselbach'striangle,
isbounded
• inferiorly by theinguinal
ligament,
• medially by the lateralmargin
of the rectus abdominisand
• superiorly by the inferior
epigastric artery.

4. ILLUSTRATION OF RIGHT
INGUINAL REGION FROM
ANTERIOR VIEW SHOWS
TRANSDUCER POSITION
TO EVALUATE FOR
(1) spigelianhernia
(2) indirect inguinalhernia
(3) direct inguinal hernia
(4) femoral hernia.
Inguinal ligament (curved
arrow), rectus abdominis
muscle(R), lateral boundary
of Hesselbach's triangle (H)
defined by inferior epigastric
artery (open arrow), and
spermatic cord (arrowhead).

5. 40-year-old manwith Sonogramof inguinal region parallel andcranial to
inguinal ligament corresponding totransducer position 2 showsspermaticcord
(C), external iliac artery (A),inferior epigastric artery (E), femoral vein (V), and
superior pubicramus(curvedarrow).

6. Patients with groin hernias typically present with an obvious lump or
bulge and are often diagnosed clinically and infrequently require
imaging
On the other hand, patients with hernias who present with pain but
without a lump or bulge are more often referred for diagnostic
imaging.
More recently, CTandMRI have been usedto identify anddescribe
hernias
However, real-time ultrasound hasadvantages over otherimaging
modalities:
• Theability to scanthe patient in both uprightandsupinepositions.
• Tousedynamic manoeuvressuchasValsalvaand compression.

7. Herniasoccur
--inareasof naturalweakness
--inareaswhere vesselspenetrate the abdominal wall (femoral and spigelian)
--wherefetal migration of testis,spermaticcord, or round ligament have
occurred(indirectinguinal)
--through broad flat tendons called aponeuroses(directinguinal).
Herniasdo not occurthrough the belly of abdominal wallmusclesunlessthey
have been surgically
WHY DOES HERNIA OCCURS ?

8. HERNIACONTENTS
Most Sonographically detected hernias do not containbowel.
In fact, most hernias contain onlyfat.
Thefat maybe intraperitoneal (mesenteric oromental)
or preperitoneal inorigin.
Generally, it isnot possiblesonographicallyto distinguishwhetherthe
hernia containsintraperitoneal or preperitonealfat.
Herniasthat containintraperitoneal fat maycontainbowellater andthus
may be a greater risk than those that containonlypreperitoneal fat
Herniasthat contain bowel are consideredhigherrisk because
strangulation maylead to infarction ofbowel.

9. Hernia showingbowel asits contents

10. SPIGELIANHERNIAS
Spigelian hernias that present clinically arerare.
Sonographically detected spigelian hernias are more
common than the literature wouldsuggest.
All hernias occur along the course of the spigelian fascia,
the complex aponeurotic tendon that lies between the
oblique muscles laterally and the rectus musclesmedially.
However, almost all spigelian hernias occur where the
posterior rectus sheath is absent, and where the spigelian
fascia is penetrated and weakened by the inferior
epigastricvessels.

11. Almost all
spigelianhernias
arise from the
inferior end of the
spigelian fascia
just lateral to
where
it is penetrated by
the inferior
epigastric vessels,
lateral tothe
lateral edge of the
rectus abdominis
muscle.

12. Image 1-The inferior epigastric artery and its paired veins lie along the midlateral
posterior surface of the rectus abdominismuscle.
Image 2-IEVslie more laterally.
Image 3 - is obtained at a level where the IEVs (arrow)lie at the edge of the
rectus muscle. Thisisthe level at which most spigelian herniasoccur.

13. 25-year-old man with right spigelian hernia. Pre-Valsalva maneuve over linea
semilunaris in axial plane corresponding to transducer position 1in Figure 4
(hernia not visible) showing right rectus abdominis muscle (R), inferior
epigastric artery (curved arrow), peritoneal fat stripe (straight arrows), and
lateral abdominal muscles(M).

14. Post-Valsalva maneuver sonogram in same location showing peritoneal fat stripe
distorted by fat-containing spigelian hernia (arrows) at linea semilunaris.
Note rectus abdominis muscle (R) and lateral abdominal muscles (M).

15. The spigelian fascia iscomposed of several different layers of loosely
apposedaponeurotic tendons.
From external to internallie the aponeurosis of the externaloblique,
internal oblique, andtransverse abdominismuscle.
Internal to the aponeurosis lie the transversalis fascia and
peritoneum.
In spigelian hernias the transverse abdominis tendon is always torn.
In most casesthe internal oblique aponeurosisisalsotorn
The external oblique tendon is always intact and usually forces the
hernia sac to extend either medially over the anterior aspect of the
rectus abdominis muscle or laterally over the external oblique muscle,
forcing it into the shapeof ananvilor mushroom.

17. Small, spigelian hernia in which the aponeuroses of both the transverse
abdominis and internal oblique muscles are torn, but in which the external
oblique aponeurosis,isintact.

18. Nonreducible left spigelian hernia containsbowel and hasanarrowneck
andbroad fundus, the typical shapefor spigelianhernias.

19. INGUINALHERNIA
In indirect inguinal hernia - herniated structures enter the inguinal
canallateral to the inferior epigastric artery andsuperior tothe
inguinal ligament, and extend for a variable distance through the
inguinal canal.
A second site of herniation is at the inferior aspect of the
Hesselbach's triangle, where a direct inguinal hernia usually occurs.
Thisweakened area isjust lateral to the conjoint tendon and medial
to the inferior epigastric artery, in contrast to the indirect inguinal
hernia that originates lateral to the inferior epigastric artery.

20. 30-year-old man with sonogram of right indirect inguinal hernia with transducer
positioned parallel to and cranial to inguinal ligament corresponding to
transducer position2.
Pre-Valsalvamaneuver sonogram(hernia not visible) showsexternal iliacartery
(A), inferior epigastric artery (E),andsuperior pubic ramus(curved arrow).

21. Post-Valsalva maneuver sonogram shows external iliac artery (A), inferior
epigastric artery (E), dilated external iliac vein (V), superior pubic ramus (curved
arrow), and indirect inguinal hernia (H) originating from lateral to external iliac
artery (arrowhead) and traversing inguinal canal from lateral to medial. (Left =
lateral).

22. Indirect inguinalhernia.
Long-axisview showsthat neck
ofthe hernia lies in the internal inguinal ring (IIR),
which lies superior andlateral to the proximal inferior epigastric artery (IEA).Hernia sac
then courseshorizontally in aninferomedial direction within the inguinal canal(IC).Indirect
inguinal herniasalwayspasssuperficial to theIEA.

23. Long-axisviews
Left, Image showsthe right direct inguinal hernia saclying posterior tothe
spermatic cord(SC).
Right, Image showsthe left indirect inguinal hernia saclying anterior to the
spermatic cord(SC).

24. Indirect inguinalhernia.
Short-axis view shows
indirect inguinal hernia
displacing andcompressing
the hyperechoic spermatic
cord posteriorly.
Direct inguinalhernia.
Short-axis view shows
direct inguinal hernia
displacing and compressing
the hyperechoic spermatic
cord anteriorly and laterally.

25. FEMORALHERNIAS
Femoral hernias are rare, because they are difficult to diagnose
clinically unless strangulated, and in fact are much lesscommon that
inguinalhernias.
Unlike inguinal hernias, femoral hernias are more common in
women thanmen.
It isthought that the increased intrapelvic pressure that occurs
during the third trimester of pregnancy together with the
hormone induced
Softening of tissues,predisposestothe development of
femoral hernias.

26. FEMORAL HERNIAS ARISE WITHIN THE FEMORAL CANAL INFERIOR TO
THE INGUINAL CANAL AND ILIOINGUINAL CREASE. THE FEMORAL CANAL
LIES JUST MEDIAL TO THE COMMON FEMORAL VEIN (CFV) AND JUST
SUPERIOR TO THE SAPHENOFEMORAL JUNCTION
The saphenofemoral junction, similar to the origin of the inferior
epigastric artery for inguinal hernias, is the key landmark for identifying
the femoral
Femoral hernias arise
within the femoral canal,
which lies medial to the
common femoral vein
just superior to the
saphenofemoral junction
and inferior to the
inguinal ligament.

27. 31-year-oldwoman with femoral hernia. Sonogram of right inguinal region parallel
to andcaudadto inguinalligament correspondingto transducerposition 4.
Pre-Valsalva maneuver sonogram shows (hernia not visible) femoral artery (A),
femoral vein(V), andsuperiorpubicramus(curved arrow).

28. Post-Valsalva maneuver sonogram shows dilated
femoral vein (V) lateral to femoral hernia (arrows).
Superior pubic ramus (curved arrow) isalsoseen.

29. LINEAALBAHERNIAS
Lineaalba hernias are anterior abdominal wall hernias thatprotrude
through the lineaalba.
Thosethat occursuperior to theumbilicusare called epigastric hernias,
andthose that occurinferior to the umbilicusare calledhypogastric
hernias.
Hypogastric hernias are much less common than epigastric hernias
because the linea alba is much narrower and shorter, inferior to the
umbilicusthan superior to theumbilicus.
Thelinea alba isathick layer of aponeurosisthat separatesthe rectus
abdominismuscles.It isformed byfusion andinterlacing of fibers of
the anterior and posterior sheathsof the right and left rectus muscles.

30. Transverse views.
A, Normal, thick lineaalba.
B,Thinner but wider linea alba, possiblyresulting from fewer decussationsof rectus
sheath fibres or representing diastasisrecti.
C,Marked thinning andbulging of the linea alba that occursindiastasisrecti.
D, Typicalsmall, epigastric linea alba hernia with its necknear the midline of the linea
alba.
E,Smalllinea alba hernia with neckoccurring eccentrically near the right edge of the
linea alba.

31. Anycauseof prolonged increasedintra-abdominal pressure can
predisposetoward weakening of the lineaalba.
Thefirst step isoften diastasisrectiabdominis.

32. Epigastriclinea alba hernias are easier todiagnosethan are groin hernias.
The defect through the linea alba isusuallyquite conspicuousbecauseit is
either isoechoic or hypoechoic compared with the extremely hyperechoic
lineaalba.
Thedefect isusuallyvery near themidline.

33. UMBILICALHERNIAS
• Umbilical hernias occur through a widened umbilicalring.
• Umbilical hernias can, however, develop at any time during
life.
• Any cause of chronically increased intraabdominal
pressure or connective tissue weakness can lead to
dilation of the umbilical ring and formation of an umbilical
hernia.
• Umbilical hernias contain intraperitoneal contents, but
smaller umbilical hernias usually contain only
intraperitonealfat.
• Untreated umbilical hernias tend to increase in size over
time.
• They are usually reducible but may become non-reducible
and canalso become strangulated.

34. Small, non-reducible, strangulated umbilicalhernia.

35. INCISIONALHERNIAS
• Incisional hernias occur through surgicalscars.
• Herniation can occur through any type of surgical scar, including
laparoscopy ports and stomal sites.
• Incisional hernias can occur in any area along the
anterior abdominalwall
• where an incision ismade.
• Incisional hernias resulting from thinning and stretching of the
scar have wide necks and are reducible, whereas those resulting
from tears in the scar are more likely to have narrow necks and
tobe nonreducible.

36. Incisional hernias canoccurwhere natural hernias cannot, through the
bellies of musclesthat have beenincised.

37. Narrow-necked, fat containing ventral incisional hernia that is
incompletely reducible, with no compressionon the right, but with
compressionon the left.

38. HERNIACOMPLICATIONS
Hernia complications include incarceration, obstruction,and
strangulation.
Incarcerated herniasare simplyhernias that arenonreducible.
Obstructed hernias contain incarcerated bowel loopsthat havebecome
mechanicallyobstructed.
Strangulated hernias contain incarcerated contents withcompromised
vascularity
Not all strangulated hernias contain bowel loops;even preperitonealfat
canbecome strangulated.
Most incarcerated hernias are neither obstructed norstrangulated,
but all obstructed andstrangulated hernias are alsoincarcerated.

39. Even strangulated hernias that contain only pre-peritoneal fat maynot
be emergencies.
It isthe presence of bowel loopswithin strangulated hernias that
makesthem emergent.
Theshapeof hernias affects their reducibility andtheir likelihoodof
becomingobstructed or strangulated in thefuture.

40. Hernia types that typically have narrow necksandareat
high risk for strangulationinclude
• femoral
• spigelian
• linea alba
• umbilical
• indirect inguinalhernias.

41. Doppler ultrasound shows arterial flow within hernias with
some success, but generally is not sensitive enough to
demonstrate venous flow and cannot show lymphatic flow at
all Thus, in strangulated hernias, the lymphatics and veins
become
obstructed long before arterial flowdecreases.

42. Themost sensitive findings ofstrangulation are the presence
of thefollowing:
• Hyperechoic fat
• Isoechoicthickening ofthe normally thin andechogenichernia sac
• Fluidwithin thesac
• Thickeningofbowel wall in bowel-containing hernias.

43. The sacnormally appears thin andechogenic.

44. Thesacwall isisoechoicandthickened, andasmall bowel loop (b) hasa
thickened wall andisaperistaltic.

45. Abnormalhyper-echogenicityof the fat within thisumbilical hernia
indicates that it isstrangulated.
ColorDoppler andpulsed Doppler spectral ultrasound analysisshows
normal flow within the hernia, despiteit beingstrangulated.

46. THANK YOU