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41 Pre-operative Portal Vein Embolization 411
Clinical Scenarios
Treatment Plan and Technique
The most common scenario is embolization of the right portal vein.
• If possible, a route is selected to access the portal vein in the left lobe of the liver.
This has the advantage of embolization being in the direction of flow in the portal
vein.
• Left-lobe puncture may be impossible, if the lobe is small.
• The right lobe of the liver may be used. Some surgeons prefer that the lobe being
preserved not be used for the embolization. If the right lobe is accessed, then
◦ Embolization of the punctured vein will be “against the flow”. Care must
be taken not to glue the catheter/sheath in the liver.
◦ Care should be paid to avoiding access through a diseased area to avoid the
risk of tumor seeding.
• Percutaneous access is performed under ultrasound control using a micro-access
set.
• The vascular sheath is positioned with the radiopaque tip visible in the portal
venous branch. Once this has been achieved, it is often helpful to suture the sheath
in place.
• Portal venography is performed (Fig. 41.2).
• A simple curved catheter without side holes can be used for selective catheteri-
zation and embolization of the target right-lobe portal vein branches.
• If glue is being used, when in position in the target branch:
◦ The catheters and syringes should all be flushed with 5% dextrose solution.
◦ Inject small aliquots of the glue mixture (0.25–0.5 ml or less) under fluoro-
scopic guidance until near stasis is achieved.
◦ Remember that the catheter contains a “reservoir” of glue which should either
be aspirated or carefully flushed through with the dextrose solution.
◦ Repeat this procedure for each branch to be embolized.
◦ Perform check-venography to demonstrate satisfactory (complete) occlusion.
• The access track should be embolized (using a Gelfoam pledget or a coil) when
the access sheath is removed (Fig. 41.3).
Additional Considerations
• If the same lobe has been accessed as for embolization, then more complexshaped catheters (Fig. 41.4) will probably be needed for selective segmental
catheterization (e.g., Sidewinder/Simmonds, SosOmni).
• If the segment used for access requires embolization, then great care should be
taken with glue, to avoid gluing the access sheath into the liver. It may be more
suitable to use particles and/or coils for this final segment (Fig. 41.3).
412 T. Cleveland
Aftercare
• As with any transhepatic procedure, pulse and blood pressure should be recorded
for 24 h in case of bleeding.
• Pain after the procedure is completed is usually minimal, as the embolized liver
segments retain their hepatic arterial supply, and so cellular ischemia/necrosis
does not occur.
Follow-Up
CT/MRI should be performed 4–5 weeks after the embolization. This can be used
for the following:
• Assess the success of the embolization (by comparison with the pre-procedural
images).
• Assess the increase in liver volume. This will influence the timing of the definitive
hepatic resection (Fig. 41.5).
• Look for development of new disease in the hypertrophied lobe and outside the
liver.
Fig. 41.5 CT scan 5 weeks after embolization with glue (same patient as in Fig. 41.1). The left
lobe of the liver has enlarged (white arrowheads). Glue and Lipiodol are seen in the right lobe
(yellow arrows), the original lesion has enlarged (red arrowhead – compare with Fig. 41.1)anda
new metastatic deposit (black arrowheads) is seen
41 Pre-operative Portal Vein Embolization 413
Keypoints
• Portal vein embolization is performed on one hepatic lobe to stimulate
hypertrophy of the other.
• Portal vein embolization does not cause hepatocellular death.
• Pre-operative imaging with CT or MRI is vital to planning.
• Small left hepatic lobes may be difficult to access percutaneously.
• Glue is a cheap (in Europe) and effective agent for embolization.
• Post-operative imaging should be performed 4–5 weeks after embolization
to plan the timing of liver resection.
Suggested Reading
1. Lochan R. Pre Operative Portal Vein Embolisation for Primary and Secondary Liver Tumours.
Cochrane Review 2008.
2. Abulkahir A; Limongelli P; Healey A; Damrah O; Tait P; Jackson J; Habib N; Jiao L.
Preoperative Portal Vein Embolization for Major Liver Resection: A Meta-Analysis. Ann surg.
2008; 247(1): 49–57
3. Hemming A, Reed I, Howard R, Fujita S, Hochwald S, Caridi J, Hawkins I, Vauthey J-N.
Preoperative Portal Vein Embolization for Extended Hepatectomy. Ann Surg. 2003; 237(5):
686–693
4. Di Stefano D, de Baere T, Denys A, Hakime A, Gorin G, Gillet M, Saric J, Trillaud H,
Petit P, Bartoli J-M, Elias D, Delpero J-M. Preoperative Percutaneous Portal Vein Embolization:
Evaluation of Adverse Events in 188 Patients. Radiology 2005; 234: 625–630
5. Gallego C, Velasco M, Marcuello P, Tejedor D, De Campo L, Friera A. Congenital and Acquired
Anomalies of the Portal Venous System RadioGraphics 2002; 22: 141–159.
6. Madoff DC, Hicks ME, Vauthey J-N, Charnsangavej C, Morello FA, Ahrar K, Wallace
MJ, Gupta S. Transhepatic Portal Vein Embolization: Anatomy, Indications, and Technical
Considerations. RadioGraphics 2002; 22: 1063–1076
Chapter 42
Epistaxis
Anthie M. Papadopoulou and Andrew Platts
Definition: epistaxis is defined as acute hemorrhage from the nostril, nasal cavity,
or nasopharynx.
Clinical Features
• Most epistaxis is self-limiting; patients tend to present if bleeding is prolonged,
heavy, or repeated.
• Severe epistaxis can be life threatening due to airway compromise and blood loss.
• Spontaneous idiopathic epistaxis accounts for approximately 80% of cases.
• Risk factors include smoking, hypertension, atherosclerotic disease, coagulopa-
thy/thrombocytopenia, and oral anticoagulant/antiplatelet agent use.
• Unusual causes of epistaxis include hereditary hemorrhagic telangiectasia, internal carotid artery aneurysm, vascular malformations, trauma, and post-surgical
complications, tumors such as juvenile nasal angiofibroma, solitary fibrous tumor
of the nasopharynx, and carcinoma of the nose and throat.
• Less than 10% of patients require treatment, and the vast majority of these will
be successfully treated by an emergency physician.
• Epistaxis is classified according to anatomic location—anterior and posterior.
◦ Anterior hemorrhage is most common; posterior hemorrhage tends to be more
severe.
Diagnostic Evaluation
Nasal Endoscopy
• This is performed to define the location of bleeding as well as to rule out
predisposing factors such as telangiectasias or neoplasm.
Transcatheter Embolization and Therapy,
Techniques in Interventional Radiology, DOI 10.1007/978-1-84800-897-7_42,
C
Springer-Verlag London Limited 2010
415
416 A.M. Papadopoulou and A. Platts
Imaging
• Radiologic assessment is not routinely required and should be tailored to the
clinical situation.
• Cross-sectional imaging with CT and MR is usually reserved for cases where a
neoplasm, trauma, or post-surgery is the suspected cause of bleeding.
• Angiography is usually only performed in the context of intervention.
Laboratory
This should not delay treatment of massive epistaxis. Some laboratory investigations
will have been performed as part of the diagnostic pathway to determine the cause
and severity of the epistaxis.
• Coagulation profile. If there is life-threatening hemorrhage, then coagulation sta-
tus and platelet count must be closely monitored to evaluate for disseminated
intravascular coagulopathy. Coagulation disorders may be the underlying cause,
and abnormalities will be exacerbated by fluid replacement and blood transfusion.
Appropriate measures should be aggressively instituted to correct coagulopathy.
Management of Epistaxis
The severity and location of the bleeding as well as any predisposing and underlying
factors determine the subsequent treatment approach.
Initial Therapy
• Airway management and resuscitation.
• Nasal packing and chemical or electrocautery are usually successful if the source
of bleeding is from the anterior septal area. Packing is first-line therapy for posterior epistaxis; the use of an epistaxis balloon as an alternative form of tamponade
is also widely advocated.
• Transantral surgical ligation of the internal maxillary artery (IMA).
• Transnasal endoscopic sphenopalatine artery ligation (TESPAL).
Indications for Embolization
• Definitive therapy for severe intractable epistaxis refractory to chemical/electrocautery, and anterior and posterior packing/balloon tamponade.
• Definitive therapy for post-traumatic pseudoaneurysms resulting in epistaxis.
• Pre-operative embolization of juvenile nasal angiofibroma and other tumors
(Fig. 42.1) can improve visualization of the surgical field and result in a more
complete and uncomplicated resection. Recent advances in transnasal endoscopic
resection techniques rely on pre-operative embotherapy to reduce intraoperative
blood loss.
42 Epistaxis 417
a
b
c
d
Fig. 42.1 Pre-operative embolization. (a) Hypervascular renal cell cancer metastasis to the lateral
nasal wall. (b) Selective catheterization of the internal maxillary artery showing tumor supply
(c) following superselective embolization of multiple feeding branched with 300–500 μ PVA, the
tumor circulation is obliterated. The patient subsequently underwent resection without blood loss.
(Courtesy Dr David O. Kessel and Dr Jai Patel)
Contraindications
These are relative in massive life-threatening epistaxis.
• True allergy to iodinated contrast is a relative contraindication to angiography.
Gadolinium chelates may be considered as an alternative.
• Other contraindications (such as renal insufficiency) are relative.
418 A.M. Papadopoulou and A. Platts
Specific Complications
The patient must be aware of and consented for the following:
• Significant rates of recurrence (up to 25%).
• Frequent post-procedure complications include facial pain and numbness, which
are often self-limiting. Skin sloughing and hard palate necrosis have also been
reported as an uncommon complication.
• Major complications include stroke and blindness.
Anatomy
Normal Anatomy
• The arterial supply to the nasal fossa is complex, involving branches from both
the internal and external carotid arteries. Multiple anastomoses are also present
(Fig. 42.2a and b).
• External carotid artery (ECA) supply
◦ Sphenopalatine and greater palatine arteries from the IMA.
◦ Septal branch of the superior labial artery, arising from the facial artery.
• Internal carotid artery (ICA) supply
◦ Anterior and posterior ethmoidal branches of the ophthalmic artery.
• Knowledge of the potentially dangerous anastomoses around the skull base
is mandatory. These may allow embolic material to pass from the extracranial circulation to the intracranial circulation during embolization resulting in
stroke or blindness. These anastomoses involve the inferolateral trunk, ethmoidal
collaterals, meningo-hypophyseal arteries, and occipital-vertebral arteries.
Aberrant Anatomy
• The commonest anomalous origin of the ophthalmic artery is from the middle
meningeal artery, which occurs in about 1% of cases.
• The infraorbital artery, a branch of the pterygopalatine segment of the internal
maxillary artery, has been shown to contribute to the nasal mucosal supply.
Equipment
Catheters
• Non-selective catheters: a pigtail catheter is sometimes needed for arch aortog-
raphy.
42 Epistaxis 419
Fig. 42.2 Arterial supply of
(a) the lateral and (b)the
medial nasal walls (courtesy
of Dr J M Harris)
• Selective catheters: Vertebral, sidewinder II, microcatheter with a 30–45
◦
guidewire with 30–45
• Guide catheter: 6Fr with a 0.067
curve.
lumen. This allows guiding contrast injections
◦
as well as continuous flushing with heparinized saline from a pressurized bag to
prevent clot formation.
• C-arm angiographic equipment with road map capability.
curve,
420 A.M. Papadopoulou and A. Platts
Embolic Agents
The choice of agent depends on the clinical context and angiographic findings.
• Polyvinyl alcohol (PVA) particles (250–300 μm).
• Gelfoam slurry/pledgets.
• Coils can be used successfully in cases when the bleeding source correlates with a
focal arterial anomaly on diagnostic angiography, and superselective single vessel embolization is possible (e.g., trauma resulting in epistaxis). Coils are not
recommended for proximal embolization in spontaneous epistaxis because they
make the distal vessel i naccessible in cases of recurrent bleeding.
• Liquid embolic agents (cyanoacrylate or Onyx
increased risk of non-target embolization.
TM
) may be used, but there is
Medication
• General anaesthesia: is necessary in cases of airway compromise, and in children
and poorly compliant patients.
• Analgesia: intravenous opiates in combination with sedatives such as benzodi-
azepines are usually administered peri- and intraprocedurally. Anti-inflammatory
analgesics are often necessary after the procedure, as patients often report
temporofacial pain.
• Antibiotics: penicillin/cephalosporin if nasal packing is present.
• Heparin: this sounds paradoxical during an embolization procedure but is nec-
essary to prevent pericatheter thrombus formation with the risk of cerebral
embolization and stroke. The patient is given a 5000 IU bolus, with 1000 IU per
hour thereafter during the embolization procedure. If available, an activated clotting time (ACT) should be used to control heparinization—the objective being to
achieve and maintain a doubling of the baseline reading.
Angiography
Access
• Common femoral artery.
Angiography
• Complete ECA angiography is imperative because bleeding can originate from
unsuspected sites such as the accessory meningeal artery or the infraorbital artery,
intracranial, and ophthalmic artery anastomoses are also identified.
• The most useful angiographic view of the ECA is the lateral view, which profiles
nearly all vessels. However, distal portions of the IMA are best demonstrated on
a frontal view.
42 Epistaxis 421
• Selective views of ECA branches are also mandatory before embolotherapy.
• ICA angiography is imperative. Although rare, aneurysms of the ICA can present
with epistaxis. In addition, demonstration of ICA anatomy prior to embolization
is important because of the presence of ECA-to-ICA anastomoses and demonstration of the supply to the ophthalmic artery. Remember that these anastomoses
may enlarge in the presence of ICA occlusion.
Angiographic Appearance
• Diffuse, bilateral mucosal hypervascularity with early venous opacification is the
most common finding in patients with intractable epistaxis. The actual bleeding
site is rarely visualized, particularly in patients who have packing in place.
• Juvenile nasal angiofibroma is demonstrated as a hypervascular mass. The blood
supply initially originates from the ipsilateral IMA, but as the tumor grows, supply is recruited from other arteries including the contralateral IMA, the ascending
pharyngeal, and ICA branches, as well as other sites such as spinal and occipital
arteries.
• Pseudoaneurysms of the ICA and vascular malformations resulting in epistaxis
can be demonstrated.
• In epistaxis following trauma, direct vessel injury is usually demonstrated and may consist of vessel laceration/transection or vessel irregularity.
Pseudoaneurysms, contrast extravasation, or arteriovenous fistula formation are
also possible findings on angiography.
Clinical Scenarios
The treatment plan and embolic agent used depend on the indication, the cause, and
location of bleeding, as well as the angiographic findings.
Treatment Plan and Technique
• Nasal packing with radiopaque materials such as bismuth iodophore paste
(BIPP)-drenched swabs should be replaced with non-opaque material prior to
angiography.
Spontaneous Epistaxis
• The nose should be packed with radiolucent material during the procedure and
unpacked at the end.
• The purpose of the procedure is not to achieve complete devascularization but to
decrease arterial inflow pressure to allow clotting and epithelial repair.