interventional radiology in surgery

1. Interventional Radiology in
General Surgery
Presented By-
Dr. Pragati Shukla (R3 S/D)
Dr. Bhargav Joshi (R3 S/D)
Mentor-
Dr Anurag Yadav
(Assistant Professor S/D)

2. Introduction
• It is a subspecialty of Radiology, in which minimally invasive
procedures are performed using image guidance.
• It is both-: Therapeutic and Diagnostic.

3. History
• Europe was an early destination for radiologists seeking training in
invasive diagnostic techniques.
• Sven Seldinger (of the Karolinska Institute in Sweden) invented
percutaneous catheterization in 1953 and revolutionized the field of
medicine.
• Berberich and Hirsch demonstrated peripheral angiography and
venography in 1923, Egas Moniz of Portugal described cerebral
angiography in 1927, Reynaldo dos Santos performed direct puncture
aortography in 1929.
• Werner Forssmann of Germany catheterized his own heart in 1929.

4. Vascular Access

5. Arterial Access
• Evaluating vessel patency proximal and distal to the site of puncture is
important to ensure successful needle entry.
• Percutaneous arterial access is most often achieved using the
Seldinger technique, first described by Sven Seldinger in 1953

6. Seldinger technique. (a) The needle is advanced at a 45-degree angle through the soft tissues and used to puncture the anterior wall of the
artery creating an arteriotomy. (b) Once return of blood is seen, the needle is advanced a few millimeters more to ensure that the needle tip is
well within the artery lumen. (c) A wire is advanced through the needle into the artery lumen. (d) The needle can then be backed out over the
wire, leaving only the wire within the artery. (e–f) A short-tapered hemostatic catheter known as a sheath can then be tracked over the wire and
into the artery providing stable and hemostatic access into the artery

7. Double-Wall Technique
• The “double-wall technique” involves inserting the needle through
both the anterior and posterior walls of the artery until the femoral
head is felt firmly against the needle tip. The needle is then slowly
withdrawn until pulsatile blood is seen.
• This technique is employed in patients with significant plaque or
when the single wall technique is otherwise unachievable.
• Both ultrasound and fluoroscopy can be helpful in identifying a
heavily calcified artery and pinpointing an area without calcification
for puncture, which may also minimize access closure complications.

8. Common Femoral Artery Access
• Due to the large size and superficial location of the common femoral
artery (CFA) anterior to the femoral head, this artery remains the
standard access point for the majority of arterial interventions today.
• Located within the femoral triangle, the CFA is anatomically bound
superiorly by the inguinal ligament, medially by the adductor longus
muscle, and laterally by the sartorius muscle.
• The inguinal ligament is the anatomic landmark between the
retroperitoneal external iliac artery and the CFA, located within the
anterior compartment of the thigh as it courses over the surface of
the femoral head.

9. • Caudally, the CFA bifurcates into the superficial and deep femoral
arteries.
• The CFA should be accessed at the level of the femoral head.
• Access above the femoral head risks retroperitoneal hemorrhage and
below the femoral head risks thigh hematoma

10. Indications:
• Thrombectomy/thrombolysis for stroke,
• Aortic aneurysm repair,
• Embolization for acute bleeding,
• Transarterial delivery of chemo- and radiotherapeutics,
• Uterine artery embolization for symptomatic fibroids
• Prostate artery embolization for benign prostatic hyperplasia,
• Treatment of peripheral artery disease.

11. Relative contraindications for femoral artery catheterization include-:
• Therapeutic anticoagulation that cannot be reversed
• Thrombocytopenia
• extensive atherosclerosis at the access site.

12. Arterial access complications-:
• Hematoma/hemorrhage
• Pseudoaneurysm
• Thromboembolic event leading to limb ischemia.

13. Radial and Brachial Artery Access
• Disadvantages with brachial artery access are-: increased total
fluoroscopy time and radiation dose relative to CFA access, risk of
brachial plexus injury, and postoperative compartment syndrome.
• Advantages to radial artery access -:
Increased patient mobility post-procedurally
Potential for earlier discharge
No need for expensive closure devices
Lower access site complication rates

14. • Radial access site specific complications -:
Vessel spasm
Access site hematoma
Pseudoaneurysm
Radial artery occlusion

15. Venous Access
Five tricks to identify a vein versus artery on USG
• Arteries are pulsatile.
• Veins are compressible.
• Direction of Doppler flow.
• Veins have valves.
• Internal jugular vein is lateral to the common carotid artery, common
femoral vein medial to the common femoral artery.

16. • Venous access can be divided into two categories – peripheral venous
access and central venous access.
• Peripheral venous access lines, including conventional peripheral
intravenous lines (PIVs) and midline catheters, and terminate in
peripheral veins outside of the thorax.
• Central venous access catheters terminate within the central veins of
the thorax, ideally at or below where the superior vena cava and right
atrium meet at the cavoatrial junction.

17. Indications for Different Central Venous
Catheters
• When peripheral access is adequate-:
<5 days: PIV
6–14 days: Midline catheter or PIV due to lower risk of complications
compared to PICCs in this time interval
>15 days: PICCs preferred to midline catheters as the failure rate of
midline catheters increases in this time period
>30 days: PICCs, TCCs, and ports

18. • When peripheral access is contraindicated or unable to be achieved:
<14 days: PICCs and non-tunneled catheters
15–29 days: PICCs
>30 days: PICCs, TCCs, and ports

19. Tools of the Trade

20. GUIDEWIRES
• Guide the catheter.
• Allow safe introduction of catheter into the vessel.
• Made of stainless steel.
• Usually about 145 cm long.
• An inner core wire that is tapered at the end to a soft flexible tip.
• Covered by a coating—teflon, heparin and recently hydrophilic
polymers (glide wires) are used.

21. • Coating reduces friction, gives strength to GW.
• Tips at the end of GW-:
Straight
J- tipped—prevents subintimal dissection of artery.

23. CATHETERS
• Many shapes and sizes.
• Diameter in French(Fr)—3Fr=1mm.
• Straight- end hole only—smaller vessels/minimal contrast.
• Pigtail- circular tip with multiple side holes —larger vessels/ more
contrast.
• H1 or Head hunter tip– used for femoral approach to brachiocephalic
vessels.
• Simmons catheter is highly curved --- for sharply angled vessels--cerebral
and visceral angiography.
• C2 or Cobra catheter has angled tip joined to a gentle curve—celiac, renal
& mesenteric arteries

24. Common catheter shapes.
1. Straight
2. Davis (short angled tip)
3. Multipurpose (“hockey-stick”)
4. Headhunter (H1)
5. Cobra-2 (cobra-1 has tighter curve, cobra-3 has larger and longer
curve)
6. Rösch celiac

25. 7. Visceral (very similar to Simmons1)
8. Mickelson
9. Simmons 2
10. Pigtail
11. Tennis racket

26. Self Expanding Stent
• Have radial force that anchors stent to target vessel as it deploys.

27. Balloon Mounted Stent
• Mounted over a balloon, expansion of the balloon causes deployment
of this type of stent.
• Precise positioning is required and is more rigid.
• These are not placed over joints as can fracture.

28. Stent Grafts
• Stent-grafts represent a combination of stent and surgical bypass
conduit technology.

29. Endovascular Filters
• Used to prevent pulmonary embolism in patients with DVT in whom
long term therapy is contraindicated.
• Commonly placed in infra-renal IVC after confirming negative jet of
renal veins.
• Can be permanent or temporary.
• Temporary filters have to be removed within 6 weeks to prevent
endothelization of the filter.

31. General Embolization Scheme and Clinical
Indications
Type of Vessel Permanent Temporary
Large vessel Coils (e.g., pulmonary
AVM
Gelfoam sponge (e.g.,
trauma)
Small vessel Particles (e.g., UFE); no
organ death
Liquid agents (e.g., renal
ablation); organ death
Gelfoam particles,
fibrillated collagen
(e.g.,chemoembolizati
on)

32. Venous Disease

33. Venous thromboembolism (VTE)
• Anticoagulation for a minimum of 3 months is the standard of care for
treatment of VTE. Catheter Directed Thrombolysis may help in high-risk
patients (i.e., massive PE).
• Pulmonary embolism-:
1. Access is achieved via either internal jugular or common femoral
approach. Ultrasound-guided access is recommended since inadvertent
arterial puncture increases bleeding risk when thrombolytics are being
given.
2. A catheter is directed through the superior vena cava (SVC) or IVC, right
atrium, tricuspid valve, right ventricle, pulmonic valve, and into the main
pulmonary artery. To avoid induction of ventricular ectopy from wire
manipulation in the heart, a pigtail catheter is used when traversing the
heart.

34. 4. A lysis catheter or thrombectomy device is then directed into lobes
with the most significant clot burden.
5. If a mechanical thrombectomy device is being used
(hemodynamically unstable patients), the thrombus is fragmented
and removed with the device.
6. If thrombolysis alone is being performed (more hemodynamically
stable patients), rTPA is infused for 12-24 hrs at the rate of 1-2 mg
per hour.

35. Deep Venous Thrombosis
1. Access is achieved via the common femoral vein for pelvic DVT and
via the popliteal or posterior tibial vein for all other DVTs,
depending on the extent of the thrombus. Ultrasound-guided
access is recommended since inadvertent arterial puncture
increases bleeding risk when thrombolytics are being given.
2. A catheter is directed through the clot and into a central patent
vein, which is confirmed with venography.
3. Based on the length of the clot, an appropriate lysis catheter is
selected.
4. If infusion is required, rTPA is infused for 12-24 hrs at the rate of 1-2
mg per hour.

36. IVC Filters

37. • IVC filters should be deployed inferior to the lowest renal vein.
Complications
• Access Site
‾ Hematoma
‾ Venous thrombosis
‾ Arteriovenous fistula.
• Device-Related
 Immediate
⁻ Failed filter deployment
⁻ Filter malposition

38. Delayed
⁻ Filter migration
⁻ Filter fracture and embolization
⁻ Filter penetration of the IVC and penetration of adjacent organs
⁻ Caval thrombosis and deep venous thrombosis

39. Dialysis Fistulae and Grafts

40. Arteriovenous Fistula
The most common types of fistulae are the radiocephalic fistula in the
forearm, the brachiocephalic fistula in the upper arm, and the
transposed brachiobasilic fistula where the basilic vein may be
surgically elevated to make it more accessible.
• Arteriovenous Graft
The arteriovenous graft consists of a piece of prosthetic tubing
interposed between an artery and a vein where the tube itself is
punctured during dialysis.
Dialysis grafts are composed of a variety of different materials: the
most common is polytetrafluorethylene with a diameter of 6 mm or
tapering from 4 to 7 mm.

41. AVG Angioplasty
• Stenosis is most commonly found at the venous anastomosis
between the distal end of the dialysis graft and the outflow vein
(~70%).
• The most common treatment of stenosis is balloon angioplasty. An
angioplasty is considered successful when there is <30% residual
stenosis.
• Balloon size should be 10% larger than adjacent normal vessel or graft
diameter and longer on both ends by 1 cm.

42. AVF Angioplasty
• Two-thirds of radiocephalic fistulae stenoses develop in the juxta-
anastomotic zone, which is within 2 cm of the arteriovenous
anastomosis.
• In contrast, brachiocephalic fistulae stenosis develops in 50% at the
juxta-anastomotic zone and upper arm, while 30% develop stenoses
in the cephalic arch (the terminal portion of the cephalic vein as it
enters the axillary vein) and the remaining 20% develop narrowing in
the central veins.
• As a rule of thumb, juxta-anastomotic fistulae are dilated to at least
6 mm and the remainder of stenoses to 8 mm. The procedure is
similar to angioplasty for an AVG.

43. AVF Failure to Mature
• The most common cause of failed AVF maturation is underlying
downstream venous stenosis.
• Stenosis most commonly occurs in the juxta-anastomotic vein, within
2 cm of the artery.
• For simple stenoses <4 cm in length, the angioplasty balloon
size is determined by the size of the adjacent normal vessel
diameter.
• When a long length of outflow vein is narrowed, a technique
called balloon-assisted maturation (BAM) can be tried.

44. Varicocele
• Percutaneous therapeutic intervention for varicocele involves injection
of hypertonic glucose and a sclerosant into the left gonadal vein via
the transfemoral approach.
• The most commonly used embolic agents in treatment of varicoceles
include coils and sclerosants.
• The mechanism of gonadal vein thrombosis with coils is a mechanical
reduction in flow, with platelet aggregation on the coils, which often
contain thrombogenic fibers.
• Liquid sclerosant embolic agents cause vessel occlusion by inducing a
thrombogenic and inflammatory reaction and endothelial damage.

45. Complications
• Vessel perforation
• Coil migration
• Nontarget embolization
• Gonadal vein recanalization
• Pampiniform plexus thrombophlebitis

46. Varicose Veins
The treatment plan usually consists of a combination of:
Endovenous thermal ablation (EVTA) or commercially available
forms of cyanoacrylate
Ambulatory phlebectomy (AP)
Ultrasound-guided foam sclerotherapy (USGFS)
Sclerotherapy of visible veins.
Surface laser treatment of reticular veins and spider veins.

47. Endovenous Thermal Ablation
• EVTA remains the standard treatment for the saphenous vein.
• This is a catheter-directed therapy performed under ultrasound guidance. The
basic maneuver is to access the GSV around the knee or the SSV in the mid-calf
and advance the catheter up to 1–2 cm below the saphenofemoral junction or
saphenopopliteal junction
• Inject tumescent anesthesia around the entire course of the saphenous vein, and
then pull the catheter peripherally while it emits heat to damage the intima and
thrombose the vein.
• The purpose of tumescent anesthesia is to prevent pain while “burning” the vein,
protect the overlying skin, protect the surrounding structures including nerves
and arteries, and collapse the vein over the catheter in order to treat it most
effectively.
• The two types of EVTA utilize either Laser energy (Endovenous laser ablation) or
Radiofrequency energy (Radiofrequency ablation).

48. Contraindications to EVTA
• Acute DVT
• Hypercoagulable state
Complications of EVTA/USGFS/AP
• DVT
• Bleeding
• Infection
• Paresthesia
• Nerve damage
• Skin burns

49. Vascular Malformations
• Super-selective catheterization of feeding vessels and use of embolic
and sclerosing agents, like n-Butyl-2-cyanoacrylate (nBCA).
• Commonly used sclerosants include ethanol, sodium tetradecyl
sulfate (STS), bleomycin.

50. The Aorta

51. Abdominal and Thoracic Aortic Aneurysms
• Abdominal Aortic Aneurysm (AAA)
• Abdominal aortic aneurysms can be categorized into four subtypes
based on the proximal extent: suprarenal, pararenal, juxtarenal, and
infrarenal.
• Society for Vascular Surgery guidelines for AAA repair:
Diameter ≥5.5 cm in men, ≥5.0 in women
Rapid enlargement, >0.5 cm/6 month period or >1 cm/year
Symptomatic
Rupture

53. Endovascular AAA repair (EVAR)
• This is a less invasive and modular aortic repair system and involves
delivering stent grafts from the access vessels, usually from the
common femoral artery.
• Deployment of the stent creates a conduit within the aorta using a
stent covered in low-porosity graft material which is sealed by
outward force at the proximal and distal contact points in order to
completely exclude blood flow to the aneurysmal sac.

55. TEVAR

56. Complications
• Access-related issues include hematoma, pseudoaneurysm or
arteriovenous fistula formation, thrombosis, and dissection.
• Endoleaks
• Contrast Nephropathy
• Spinal Cord Ischemia

57. Aortic Dissection

58. • Endovascular procedures treat two of the most lethal complications
of acute aortic dissection, false lumen rupture and malperfusion
syndrome.
• Thoracic endovascular aortic repair (TEVAR), fenestration with or
without stenting, or a combination is employed in these patients.
• The guiding principle of endovascular treatment is to define the
anatomy of the dissection, the location of the entry tear with respect
to nearby critical vessels, and the mechanism (static or dynamic) of
arterial obstruction.

59. • When the arterial anatomy prohibits deployment of a stent graft, or
when malperfusion persists despite coverage of the entry tear,
fenestration or stenting (or both) can treat the recalcitrant branch
vessel obstruction in a targeted, piecemeal fashion.
• The goal of the fenestration is to create a large, controlled tear in the
dissection flap separating the true and false lumens, allowing blood
flow and pressure equilibration across the flap to reperfuse branches
of the true lumen that have been excluded by the dissection

62. Traumatic Aortic Injury

63. Classification of traumatic aortic injury

64. Abdominal/Pelvic Arterial
Interventions

65. Mesenteric Ischemia
Acute Mesenteric Ischemia-:
• Endovascular management of acute mesenteric ischemia is an important
therapeutic option for early revascularization and may be used as an
adjunct to surgical management.
Embolic and Thrombotic AMI:
• When acute thrombus is present, flow is re-established to the occluded
artery via selective injection of thrombolytic agents (4-12 mg of tPA),
suction thrombectomy, or mechanical thrombolysis.
• If there is underlying significant atherosclerotic lesion, percutaneous
transluminal angioplasty and balloon-expandable stents are employed.
• If the lesion is too narrow to allow passage of a balloon-expandable stents,
lower profile balloons may be used to predilate.

66. Nonocclusive Mesenteric Ischemia (NOMI)
• Treatment involves reversal of any existing causes of hypotension
and/or pharmacological sources of vasoconstriction.
• Intra-arterial SMA infusion of papaverine may be used until symptoms
resolve.

67. Chronic Mesenteric Ischemia
• Significant stenotic lesions are defined as:
>60% diameter narrowing
70–80% reduction in cross-sectional area
≥20 mmHg systolic trans- lesional pressure gradient at rest
• For ostial lesions, balloon-expandable stents are generally preferred.
• Lesions within the trunk of the mesenteric arteries may be treated
with either balloon-expandable or self expanding stents.
• Pharmacologic adjuncts include IV heparin of 3000–5000 IU with a
target activated clotting time (ACT) of >220 s.
• Aspirin 81–325 mg/day for life and clopidogrel 75 mg/day for at least
3–6 months should also be prescribed.

69. Visceral Aneurysms
Visceral Artery True Aneurysms (VATAs)-:
• VATAs occur due to vessel wall degeneration with a defect in the
arterial media, loss of the elastic fibers, and decreased smooth
muscle volume.
• Atherosclerosis, fibromuscular dysplasia, congenital syndromes, and
collagen disorders are all precursors to VAAs.
• The most common VATAs is the Splenic artery followed by the
Pancreaticoduodenal arcade.

70. Visceral Artery Pseudoaneurysm (VAPA
• Visceral artery pseudoaneurysms occur most commonly due to
chronic inflammation caused by conditions such as pancreatitis,
infection or vasculitis, blunt, or penetrating trauma or iatrogenic
etiologies such as surgery or percutaneous procedures.
• The most common site for VAPAs is the Hepatic artery.

71. • Interventional techniques for treating VAAs include:
1. Embolization of inflow (front door) and outflow (back door)
branches +/− packing of the aneurysm
2. Stent-graft placement +/− packing of the aneurysm to preserve
parent vessel flow
3. Percutaneous embolization

72. Embolization of artery proximal and distal to the aneurysm sac-:
• This is a commonly used method for both VATAs and VAPAs and can
be easily accomplished with coils and vascular plugs.
• Permanent embolic agents are necessary with this technique to
prevent recanalization of the arterial supply to the aneurysm sac.
Exclusion of aneurysm sac with stent graft-:
• This is the preferred method of aneurysm exclusion for both VATAs
and VAPAs when distal perfusion to an organ is necessary(e.g., a
proximal SMA or splenic artery aneurysm).
Packing aneurysm sac with coils-:
• Packing of saccular aneurysms may allow preservation of parent
vessel flow. Dense packing is mandatory to assure initial thrombosis
and prevent the recognized risk of coil compaction and subsequent
reperfusion.

73. Packing aneurysm sac with coils after uncovered stent placement-:
• This is another method for preserving parent vessel flow.
• A bare stent is placed across the aneurysm and a microcatheter
advanced through the stent interstices to pack the aneurysm around
the stent.
Percutaneous embolization-:
• The aneurysm is directly punctured using CT, ultrasound, or
fluoroscopic guidance.
• Coils, tissue adhesives and 100-200 units of thrombin are injected
into aneurysm until thrombosis of the sac is achieved.

75. Splenic Artery Aneurysms
• Exclusion of splenic aneurysms can be accomplished via three main
techniques:
Stent-graft placement across the aneurysm neck. This may be the
preferred option, when possible, because it maintains perfusion to the
spleen, preventing possible infarction. This frequently cannot be
accomplished due to the tortuosity of the splenic artery.
Filling the sac with coils or other embolic agents.
Exclusion of the sac via embolization of proximal and distal branches.
Both sides of an aneurysm must be embolized as collateral flow to the sac
can occur in a retrograde fashion via pancreatic and short gastric arterial
branches.

77. Hepatic Artery Aneurysms
• Hepatic artery aneurysms are the second most common VAA,
accounting for approximately 20% of cases.
• Embolization of both inflow and outflow arteries is essential because
of the extensive arterial collateral supply and risk of retrograde
reperfusion.
• Hepatic ischemia is rare due to the portal vein supply of the liver.

78. Renal Artery Aneurysms
• More proximal aneurysms can often be managed with stent-graft
deployment or aneurysm sac embolization.
• However, for distal aneurysms, embolization techniques will often
involve at least some degree of infarction; attempts should be made
to minimize this to preserve renal function.

79. Renal Artery Stenosis
• For patients with significant RAS due to Fibromuscular Dysplasia,
Percutaneous transluminal renal angioplasty (PTRA) alone has been
shown to be effective for most patients and is associated with a >95%
procedural technical success rate.
• Renal artery stenting is indicated in patients with clinical sequela
related to a RAS and a hemodynamically significant translesional
pressure gradient and a urine albumin to creatinine ratio less than or
equal to 22.5.

80. GI Bleeding
Indication for UGIB angiography:
• Inability to control the bleeding with endoscopy
• Rapid recurrence after endoscopic therapy
Indication for LGIB angiography:
• First-line therapy for bleeding
• Bleeding demonstrated on tagged RBC scan or CTA

81. • Angiographic embolization is the front-line therapy.
• The first embolization procedure to stop GI bleeding was reported by
Baum et al. in 1974.

82. • If a patient has a coagulopathy, embolization with coils alone is
associated with a higher rate of rebleeding.
• Multiple studies have shown that n-butyl cyanoacrylate glue (super-
glue) can more effectively occlude vessels in the face of coagulopathy.
However, safe use of glue requires considerable expertise.
• Coils are usually able to be placed very precisely and tend to be used
more frequently.

83. Which vessel to select first on angiography:
Celiac first for suspected UGIB
SMA first for suspected bleed of the small bowel or right colon
IMA first for suspected bleed distal to the transverse colon
• Post procedure, the patient has to be kept at bed rest with the leg
straight to allow the femoral puncture site to seal and to avoid
bleeding.
• Vital signs must be monitored for several hours post-angiogram to
look for hypotension or tachycardia which might indicate bleeding.
• The groin and peripheral pulses must be checked with each vital sign
check to make sure there are no puncture site complications.

84. • Risk factors for embolization:
Bowel ischemia
Bowel infarction
Nontarget embolization

85. Uterine Artery Embolization
Indications for UAE-:
• Fibroids
• Adenomyosis
• Postpartum hemorrhage
• Uterine AV fistula
• Dysfunctional uterine bleeding
• Trauma

86. Prostate Artery Embolization
• Control of hematuria associated with prostate carcinoma (Gelfoam,
coils, or polyvinyl alcohol (PVA) may be used).
• Patients with LUTS and evidence of bladder outlet obstruction (BOO),
who have failed medical therapy .