Carotid injury 23-1-20179.08 pm

For Other powerpoint presentatioins of “ Skull base 360° ”

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Prepartion of this PPT also contributed by

Dr. Narendra Kumar Veerasingamani MS(ENT) DLO. with Prof.Ugo Fisch

INDIA

Carotid rupture video – click

https://youtu.be/6SC6clYnwPY

BEST PROTOCOL , I have ever seen so far – BY Dr.Paul Gardner

---- copy & paste & see in any picture software

Regarding anterior skull base when there is rupture of carotid only 3 options are

1. Covered stents 2. Clamping 3. Coilling .

Covered stents which can be passed into parasellar carotid told to me by vascular neurosurgeon – This is a big boon to anterior skull base approach –Several seniors opinions has to be taken regarding longterm effects of these stents

http://www.ncbi.nlm.nih.gov/pubmed/25415067 http://www.ncbi.nlm.nih.gov/pubmed/25790070 http://www.ncbi.nlm.nih.gov/pubmed/15337877

Benign with recurrence esp.of post RT or malignancy with radical resection when Balloon Occlusion test fails first we must do ECA-ICA anastomosis . This ECA-ICAanastamosis done by

pterional /FTOZ approach & tumor can be removed by same approach or combined with endoscopic endonasal or trans-temporal skull base approaches . We shouldn't go only by

endoscopic endonasal without ECA-ICA anastomosis because there won't be cross circulation if ICA ruptures . Leads to catastrophie. Check others at " Carotid injury " PPT & "Decision

making of anterior & lateral skull base " PPT at www.skullbase360.in

first thing we have to check BOT .• 1. If cross circulation is not there there is no point in going for surgery . So

direct Shunting has to be done . Surgery has to be done after 6 - 8 weeks .

• 2. If cross circulation good we can proceed for surgery with muscle patch & interventional radiologist ready . Even then there are higher chances of death .

• 3. So in revisions & post radiotherapy especially chordomas cases pre-op carotid coilling which completely occludes the carotid has to be done . Then you have to remove tumor . Even then in children it gives false sense of security . In adults we can safely remove tumor . Even then if the rent is more than 1.5 cm coilling may come out . But this is absolutely safe procedure

• I will write /update in detail in few days

1. Acromegaly2. Post -irradiated 3. Revision 4. Fibrous5. Chondroma & chondrosarcoma 6. Bromocriptine therapy

Above are potential factors for carotid rupture

So pre-operatively we have to check1. Ballon occlusion test ( BOT ) 2. BOT under hypotention - hypotention because once there is carotid rupture the patient has to sustain cross flow under hypotention ( so interventional radiologist checks cross flow under hypotention pre-operatively in operation theatre ) 3. Venous return less than 2 to 3 seconds 4. Color dolplar of brain with cross flow 5. In USA xenon test etc etc are there

If all these are satistfied that case is BOT is passed

If BOT is NOT passed1. Anterior skull base is contraindicated . " Carotid locking " means proximal & distal control of carotid possible only in lateral skull base ( Pterional / FTOZ ) .2. First shunting has to be done by pterional / FTOZ approach3. Tumor resection in any skull base has to be done after 2 to 3 months once shunting flow is satisfied , even excision of diseased carotid can be done

If BOT is passedwe have to do coiling of carotid & proceed by anterior skull base approach . Even then coiling gives false sense of security . Suppose if the carotid rent is more than 1 cm it may become a unmanageable situation

4 . Without pre-op coiling , with or without BOT if you proceed anterior skull base approach you have 3 options if carotid rupture occurs

a) Muscle plug -very difficult sometimes

b) Covered stent -means like our coronary bypass stent flow is patent inside of stent . But make sure that your interventional radiologist is capable to pass in parasellar carotid or not . Sometimes passing covered stent is difficult to pass in C-shaped parasellar carotid. More over there are chances of migration of covered stent to origin of opthalmic artery & risk of blindness . So pre-operatively we have to check ECA - OA ( opthalmic artery ) anastamosis by middle meningeal artery ( MMA ) . Then even if the covered stent ( or coiling ) migrates & occludes ophthalmic artery nothing happens ( means blindness won't come ) . Therere are instances where post-operative pseudo-aneurysms includes parasellar carotid including the origin of opthalmic artery . Then we must block opthalmic artery origin also which is above UDR ( upper dural ring ) . Then pre-operatively we have to check ECA - OA anastamosis by MMA or else blindness comes . With covered stents we have to give life long aspirin . Prof. Mario Sanna pre-operatively pass covered stents in these high risk cases & do subadvential dissection of carotid after 1 to 2 months of passing covered stent . In this 1 to 2 month neo-intima forms & even if you do subadvential dissection rupture won't happens

c) Direct permanent clamping by aneurysmal clamps . If you don't check BOT pre-operatively & unluckily if that patient has to NO cross flow , that patient lands up in hemiplegia or death . Luckly if that patient has sufficient cross flow nothing happens . With this lucky situations in our career of previous experiences we should not presume that nothing happens with direct permanent aneurysmal clamping & I don't check BOT & with my skills I can peel off tumor . So pre-op BOT under HYPOTENTION is a must in all carotid encircled tumor cases especially high risk carotid rupture cases ( if 2 or 3 factors present it is even more riskier status like for example acromegaly & post-irradiated ) Even we peel of tumor in high risk cases there are high chances of carotid aneurysms post-operatively [ sometimes carotid micro-aneurysms present pre-operatively ] & regular followup is necessary & again at that time BOT & coiling is a must .

5. Even in JNAs revision we have to do pre-operative coiling especially post-irradiated & in children

6. Always patient safety is more important than our surgical skills & must follow carotid management principles

JNA surgery by 4 corridors approach - by Dr. James K. Liu - I feel this 4 corridor is safest surgery for intracavernous & intracranial extension JNAs rather than removing only by nose. Orbitozygomatic transcavernous gives proximal & distal control of ICA . Endoscopic Caldwell-Luc ( Tranasmaxillary ) preserves Nose anatomy – see video https://www.youtube.com/watch?v=ekwOfEmHGWg&feature=youtu.be

Prof. Laligam Sekhar says - When the ICA is invaded or encased by tumor, two controversies continue to rage. 1. The first is whether one should attempt to

skeletonize the vessel by removing tumor or whether the vessel should be resected.

2. The second concerns the question of whether all patients should be revascularized, or only those whose collateral circulation is demonstrated tobe limited.

Whether or not the ICA should be left intactdepends on the surgeons attitude and the nature ofthe tumor. Benign tumors other than meningiomas(e.g. schwannoma, pituitary adenoma) may usuallybe dissected from the ICA. With meningiomas,however, encasement and narrowing of the ICAfrequently indicates that the vessel wall has been invaded by tumor. This has been conrmed by histologicalstudy of removed arteries [19]. Therefore,total resection often requires ICA resection. Ofcourse, the surgeon may choose to leave tumorbehind and treat it with radiosurgery. Generally,chordomas and chondrosarcomas can be dissectedfrom the ICA, but some require replacing the arterywith a bypass graft. With slowly growing malignanttumors such as adenoid cystic carcinomas, totaltumor removal requires resection of the ICA-CS.Furthermore, resecting and replacing the artery encasedwith tumor allows the surgeon to give the taskof preserving cranial nerves his full attention.

Should a revascularization procedure be performed in every patient where tumor resection creates jeopardy for the ICA, or only in those who fail preoperative balloon-occlusion testing? This is a hotly debated issue, but the occurrence of stroke even when excellent collateral circulation is present convinces us that a bypass should be performed every time tumor resection places the ICA at risk.

Our [ Prof. Laligam sekhar ] patients also undergo cerebral angiography.Collateral circulation and tolerance to temporaryocclusion is assessed by compressing the ipsilateral common carotid while injecting contrast material into the contralateral ICA and the dominant vertebral artery. We no longer perform balloon occlusion tests since we revascularize all patients in whom ICAresection or injury seems likely.

When considering sacrifice of the ICA, either 1. electively because of tumor involvement or as an 2. emergency following an accidental injury, the adequacy of the brain blood supply after exclusion of the artery has to be assured before the sacrifice. In such clinical scenarios the patient should undergo six-vessel angiography with BTO applying radiological, clinical, and functional perfusion criteria to evaluate the cerebrovascular system.

If a patient does not tolerate vessel occlusion, generally there are two ways to maintain brain blood supply: 1. revascularization by a bypass or 2. stenting of the ICA.

Management of carotid artery injury in anterior skull base

- Reference from PJ Wormold

• In Aldo Stamm book it is mentioned that while managing the Internal carotid artery - " Suture repair is possible ,albeit technically difficult and in most instances impractical . " http://books.google.co.in/books?id=5dczLBfolBcC&pg=PP7&dq=aldo+cassol+stamm&hl=en&sa=X&ei=iM85UoeeNYOtrAehwYHIAQ&ved=0CDsQ6wEwAg#v=snippet&q=Suture%20repair%20is%20possible%20%2C%20albeit%20technically%20difficult&f=false

• Saleem Abdulrauf Dear Dr Murali, you are indeed correct, it is essentially impossible to get complete control of the ICA through a standard ant skull base approach. The Lateral approach, with extra-dural exposure of the ICA (petrous segment) just below GSPN and just post to V3 allows ample proximal control. I do not recommend operating on any tumor that is wrapping the ICA without proximal and distal control. If there is a hole in the ICA, DO NOT try to bipolar it, it will make the whole bigger. In this situation, a proximal and a distal temporary clips to be placed, and then use a 9-0 prolene to suture. If not experienced in micro-suturing, then place a sundt clip, which is a circling clip that covers the hole and leaves the parent vessel open.

Incidence

• The incidence of carotid artery injury in endoscopic sinus surgery is rare, with only 29 case reports described in the literature.

• The incidence is higher in transsphenoidal pituitary surgery at 1.1% and higher still in extended endonasal approaches, such as for craniopharyngiomas, clival chordomas, and chondrosarcomas, at 5 to 9%.8

Anatomy

• The bony wall overlying the ICA is less than 0.5 mm thick and is not sufficient to protect the artery.

• some authors also describing the distance between both ICAs within the sphenoid to be as close as 4 mm.

High risk• Factors such as

1. previous radiotherapy, 2. revision surgery, 3. bromocriptine therapy, and 4. acromegaly 5. Chondroid tumors [ chordoma, chondrosarcoma ] are helpful

to identify the at risk patient.

• These patients may warrant preoperative assessment of collateral cerebral circulation if their risk is deemed high enough.

Chondroid tumors [ chordoma, chondrosarcoma ] have the greatest risk of ICA injury, and preoperative carotid balloon test occlusion should be considered for these tumors when there is significant ICA involvement.

Must read paper “ Carotid Artery Injury During Endoscopic Endonasal Skull Base Surgery: Incidence and Outcomes ” - - - http://www.ncbi.nlm.nih.gov/pubmed/23695646 - try to get the this paper from www.sci-hub.bz or www.sci-hub.cc

Tumors Involving the CavernousSegment of the Internal Carotid Artery

1. Meningiomas in this region tend to be supplied by branches of the ICA in contrast to the usual supply from external carotid branches. Taken together, in these patients assessment of cerebral blood flow and, if necessary, preparation for revascularization procedures prior surgery of the lesion itself are mandatory.

2. A transcranial approach can provide superior vascular control and m ay be preferable if a large-to-giant fibrous tumor.

3. Extension into the cavernous sinus region, which happens in about 6 to 10% of cases, may exert pressure on the cranial nerves III, IV, V, and VI, resulting in oculomotor dysfunction, ptosis, trigeminal neuralgia, or diplopia. Clinical signs are mostly absent in tumors that involve the ICA; even complete encasement of the vessel does not necessarily result in functional flow impairment or neurological deficits.

To get any paper of any journal free click www.sci-hub.bz or www.sci-hub.cc

How to get FREE journal papers in www.sci-hub.bz or www.sci-hub.cc

1. When same paper published in different journals , the same paper has different DOIs -- so we have to try with different DOIs in www.sci-hub.bz orwww.sci-hub.cc if one of the DOI is not working.

2. If the paper has no DOI , copy & paste URL of that paper from the main journal website . If you can't get from one journal URL try with different journal URL when the author publishes in different journals .

3. Usually all new papers have DOIs . Old papers don't have DOIs . Then search in www.Google.com . Old papers are usually kept them free in Google by somebody . Sometimes the Old papers which are re-published will have DOIs. Then keep this DOI in www.sci-hub.bz or www.sci-hub.cc

4. Add " .pdf " to title of the paper & search in www.Google.com if not found in www.sci-hub.bz or www.sci-hub.cc

MethodStep-1. Two surgeons are engaged, allowing one surgeon to control the bloodstream, directing it away from the endoscope, while the other obtains visualization to attempt hemostasis ( Fig. 1). ►

Step-2. Two large-bore (10F) suction devices and, if available, a lens cleaning system for the endoscope should be used. Or…..

Step-3. The second surgeon uses suction downside the nose with predominant bleeding to direct flow away from the other side

Step- 4. The primary surgeon places the endoscope down the contralateral side, using the posterior septal edge as a shield from the blood flow.

Step- 5.The primary surgeon clears blood ahead of the endoscope using the second suction device. A pedicled septal flap should also be cleared and pushed into the nasopharynx.

Step-6.The second surgeon is then free to “hover” the suction device directly over the site of injury to help gain visualization for the primary surgeon.

Hemostasis can be…• Emergency ligation in the neck- it causes stroke or even

death.• Nasal packing• Ipsilateral common carotid artery compression.• Bilateral common carotid artery compression with

concurrent surgical widening of the sphenoid sinus ostium, to facilitate nasal pack placement.

• Packing agents are teflon and methyl methacrylate patch, fibrin glue, Gelfoam, oxidized cellulose packing thrombin-gelatin matrix, oxygel, and glue and muslin gauze.

Muscle patchThe crushed muscle patch was the only method that succeeded in gaining hemostasis in all instances.

In the clinical setting, muscle is harvested from the thigh (usually prepared for fascia lata graft in skull base cases) or sternocleidomastoid in the neck.

A 2 1.5 1-cm graft is harvested then crushed

between two metal kidney basins and, after gaining control of the surgical field, it is placed directly over the injury site with Blakesley forceps ( Fig. 2).►

Muscle patch• It should be placed with enough force to stay

in contact with the vessel injury site but should not compress or occlude the vessel, and it may take up to 12 minutes to gain hemostasis.

• If the carotid is likely to be exposed to the nasal cavity, the muscle patch should be reinforced with an overlying septal flap.

• If the vessel is intracranial, the patch should be secured with oxidized cellulose and fibrin glue.

Direct vessel closure• Valentine et al used of U-clip anastomotic device to

repair the injury site after clamping with a Wormald endoscopic vascular clamp and found it to be very effective in gaining hemostasis in an animal model of carotid catastrophe.

• Padhye et al studied different carotid injury types and their long-term complications and found that a T2 Aneurysm Clip was able to gain hemostasis in all injury types as well as prevent pseudoaneurysm occurrence in an animal model of carotid bleeding ( Fig. 3). ►

Endovascular Techniques • In some patients, hemostasis may not be achievable, and

in these cases urgent transfer for endovascular intervention must be sought. These interventions are designed to either occlude the vessel or maintain vascular flow

• Endovascular occlusion of the artery is generally performed using a balloon or coil and should be performed at the wall defect to prevent extravasation of blood from both anterograde and retrograde vessel filling.

• Deployment of an endovascular balloon or coil can be associated with distal migration due to the high-pressure, high-flow environment of the artery.

Balloon occlusion test (BOT)• In addition to angiography, balloon occlusion test of

the ICA in combination with electroencephalogram, transcranial Doppler, xenon-CT, and single-photon emission computed tomography are useful to assess the collateral circulation.

• BOT may not always be possible in the emergency situation, where hemostasis has not been achieved and occlusion intervention may be the only way to save a patient’s life.

https://www.youtube.com/watch?v=EGNgCN1fUdQ

BTO decision-making algorithm to indicate extracranial–intracranial bypass surgery:

a) Patients who exhibit neurological deficits or demonstrate an asynchronous filling of the transverse sinus >1 second will need revascularization with a large-caliber graft.

b) Patients demonstrating >50% decrease in baseline perfusion will qualify for a medium or large caliber graft.

c) Patients with 30 to 50% decrease in baseline perfusion will need a small caliber bypass.

d) In patients with <30% reduced baseline perfusion, the cerebrovascular reserve capacity should be assessed by acetazolamide stimulation. If the increase is impaired, a small caliber bypass is recommended.

Currently, an angiographic assessment of the balloon test occlusion alone is considered insufficient to reliably identify patients that are at increased risk for stroke, and therefore need revascularization prior to sacrifice of the ICA. This is primarily due to a false-negative rate of the test of 10 to 15%. Consequently, additional direct or indirect monitoring of cerebral perfusion has been suggested.

When considering sacrifice of the ICA, either electively because of tumor involvement or as an emergency following an accidental injury, the adequacy of the brain blood supply after exclusion of the artery has to be assured before the sacrifice.

In such clinical scenarios the patient should undergo a six-vessel angiography with BTO applying radiological, clinical, and functional perfusion criteria to evaluate the cerebrovascular system.

If a patient does not tolerate vessel occlusion, generally there are two ways to maintain brain blood supply: revascularization by a bypass or stenting of the ICA.

BTO decision-making algorithm to indicate extracranial–intracranial bypass surgery:

a) Patients who exhibit neurological deficits or demonstrate an asynchronous filling of the transverse sinus >1 second will need revascularization with a large-caliber graft.

b) Patients demonstrating >50% decrease in baseline perfusion will qualify for a medium or large caliber graft.

c) Patients with 30 to 50% decrease in baseline perfusion will need a small caliber bypass.

d) In patients with <30% reduced baseline perfusion, the cerebrovascular reserve capacity should be assessed by acetazolamide stimulation. If the increase is impaired, a small caliber bypass is recommended.

Types of extracranial–intracranial bypass:

a) Standard /low flow bypass : STA-MCA bypass: the frontal or parietal branch of the superficial temporal artery is anastomosed to a cortical branch of the middle cerebral artery (blood flow 20–70 mL/min).

b) Intermediate -flow bypass : Radial graft artery interposition between external carotid artery and the middle cerebral artery (blood flow 60–100 mL/min).

c) high-flow bypass : Saphenous vein graft interposition between external carotid artery and the middle cerebral artery (blood flow 100–200 mL/min =).

Intraoperative assessment of bypass function should be verified by ICG videoangiography, neurophysiological monitoring, thermal di usion probe, and LASCA.

Bypass surgery or stenting and subsequent tumor surgery should be performed as a two-staged procedure: once the blood flow to the brain is secured the tumor can be removed in a separate session.

Algorithm for decision making in revascularization surgery for carotid artery sacrifice.CBF, cerebral blood flow; STA-MCA, superficial temporal artery to middle cerebral

artery.

Stent graft

• An alternative to occlusion intervention is placement of a stent graft to seal the injury site and maintain vascular flow. This is, however, technically challenging to place in the tortuous cavernous carotid siphon; stent grafts are also associated with distant migration as well as ICA spasm.

Postoperative Considerations • Postoperative care largely involves the prevention

of potential complications of carotid artery injury, which include pseudoaneurysm formation and caroticocavernous fistula.

• A pseudoaneurysm is a tear through all layers of an artery with persistent flow outside the vessel into a space contained by surrounding tissue. Its incidence after carotid artery injury can be as high as 60% and carries with it a risk of rupture for up to 3 months.

• Therefore prompt identification and treatment is required for successful longterm management.

Protocols• Once hemostasis has been achieved

intraoperatively,

• the patient should be transferred for urgent angiographic investigation to assess the repair and ascertain if further endovascular intervention in required.

• If the immediate postoperative angiogram is normal

• monitor the patient in ICU until the packing is removed and another angiogram is performed, usually at 1 week postsurgery.

• If this is again normal, then the angiogram is repeated at 6 weeks, 3 months, and 1 year.

If pseudoaneurysm is detected,

stent graft placement isolated endovascular occlusion of

aneurysm lumen

Surgery (bypass

or aneurysmal clipping)

safest option

As extracranial/intracranial surgery has a relatively high complication rate

Discussion

• several important steps that a surgeon can take to successfully manage this complication.

• First, optimal preoperative assessment with preoperative planning for such a potential complication is important.

• Second, skilled operative maneuvers can successfully achieve hemostasis.

• Third, postoperative assessments and comprehensive management of potential complications will result in the best possible outcome for the patient.

• Nasal packing has been widely described as the method of choice; however, overpacking has been seen to incur its own complications secondary to compression of critical neurovascular structures.

• Use of a crushed muscle patch has been shown to be effective in gaining primary hemostasis and maintains normal vessel characteristics in more than one injury type. However, it has been associated with destabilization and pseudoaneurysm if used as the lone treatment.

• If the surgical field permits, direct vessel closure techniques such as the U-clip and the T2 aneurysm clip have been shown to be effective in a sheep model of carotid bleeding.

• The aneurysm clip was not associated with pseudoaneurysm formation; however, placement may influence long-term carotid flow.

• If hemostasis cannot be achieved promptly, packing and transfer for angiography and endovascular intervention with balloon, coil, or stent graft is indicated.

1. Prevention and management of carotid artery injury is a combination of appropriate patient selection, surgical competency, and teamwork, culminating in the formulation and execution of a surgical plan.

2. In this anxiety provoking situation, the need for appropriate training cannot be underestimated.

3. In addition to clinical training, targeted vascular workshops utilizing cadaveric and live animal specimens will help surgeons acquire technical expertise as well as skills in teamwork and plan formulation necessary to gain the most favorable outcome for the patient.

Carry home message

Prof. Amin Kassam says in bookhttp://books.google.co.in/books?id=16y4UJEHjr8C... " With pituitary surgery, the ICA is most susceptible to injury at the medial opticcarotid junction where the parasellar ICA courses medially. Other risk factors for ICA injury include prior surgery or radiation therapy, anatomical variations, and tumor encasement or displacement of the ICA. If there is an injury to the ICA, the goals of treatment are to maintain cerebral perfusion, obtain focal control of the hemorrhage, and transport the patient to angiography for definitive management of the injury. Contrary to common practice, the blood pressure should not be lowered to decrease bleeding since this may result in cerebral hypoperfusion. Neurophysiological monitoring is invaluable in this situation to reflect cerebral perfusion and establish thresholds for blood pressure. Immediate treatment options include bipolar electrocauterization,compressive packing, direct suture repair, clip reconstruction, and ligation of the vessel. If there is a very small laceration or avulsion of an arteriole fromthe wall of the ICA, this can be sealed with careful use of bipolar electrocautery. If theinjury is substantial, the hemorrhage is directed up the suction to maintain visualization while focal packing (cottonoid) at the site of the vascular injury provides temporary control.

If this is effective and neurophysiologic monitoring stable, additionalpacking can be placed while the patient is transferred to angiography for definitivemanagement. If packing does not control the bleeding, it is best to get further controlprior to transfer. While the vessel is compressed with focal packing, additionalbone can be removed to better expose the vessel proximal and distal to the site ofinjury. Although direct suture repair is possible, it is technically difficult and may notbe a realistic option. With adequate exposure vessel preservation can be attemptedthrough aneurysm clip reconstruction (e.g. Sundt- Keys clips). Otherwise, the vesselcan be occluded with additional packing or placement of aneurysm clips. If packingis used, it needs to be focal so that bleeding is controlled and blood is prevented fromtracking through a craniotomy defect intracranially. The patient is then transportedto radiology for angiographic assessment and treatment. Preservation of blood flowwith a covered stent is technically difficult in the region of the cavernous sinus andcurrently not FDA approved; therefore, permanent occlusion with coils is often thepreferred option. Assessment of collateral blood flow is then performed to assess therisk of ischemic stroke and the potential need for revascularization (bypass).

Management of carotid artery injury in Lateral skull base

- Reference from Prof.Mario Sanna

Prof.Mario Sanna - Management of great vessels in Lateral skull base – lecture – click

https://www.youtube.com/watch?v=7tW3Ev9siCs&feature=youtu.be

Modalities of surgical management of the ICA include:

1. Skeletonization2. Displacement3. Subperiosteal/subadventitial dissection 4. Dissection and resection after permanent balloon occlusion5. Subadventitial dissection after reinforcement with stent

1. Skeletonization

This is done in tumors reaching but not adhering to the artery. The most common lesions are represented by petrous bone cholesteatomas and type C1 glomus tumors. The artery can be exposed in certain approaches to provide proximal control, e. g. the infratemporal fossa approach or the modified transcochlear approach type A. In the middle fossa transpetrous approach the artery is one of the anatomical boundaries that are skeletonized to avoid injuring while drilling the petrous apex. Skeletonization carries little risk in experienced hands. An exhaustive knowledge anatomy is mandatory; a large diamond burr parallel to the course of the artery is used to remove the last shell of bone covering the artery.

2. DisplacementDisplacement is used to gain access, e. g., during an infratemporal fossa type B approach to the petrous apex . Displacement should be done gently and complete liberation of the artery is needed first.

A case of right clival chordoma. The vertical internal carotid artery (ICA) is gently displaced to allow proper control of the petrous apex (PA) lying medial to the artery.

3.Subperiosteal/Subadventitial Dissection

Subperiosteal/subadventitial dissection is accomplished fortumors that involve the ICA to a greater extent, such as C2glomus tumors and meningiomas (Fig. 15.24a, b). In general,dissection of the tumor from the artery is relatively easierand safer in the vertical intrapetrous segment, which isthicker and more accessible than the horizontal intrapetroussegment.A plane of cleavage between the tumor and the arteryshould be found first. In most cases, the tumor is attached tothe periosteum surrounding the artery. Dissection is betterstarted at an area immediately free of tumor. Aggressivetumors may, however, extend even to the adventitia of theartery and subadventitial dissection may be needed. Thisshould be done very carefully in order to avoid any tear to thearterial wall, which can become weakened (Fig. 15.25), withthe risk of subsequent blowout.

A case of left glomus jugulare tumor in our early experience.Subadventitial dissection has been performed because the artery had

been so weakened after the tumor removal. Although the patient had norelevant complications postoperatively, such excessive manipulation is

better avoided and permanent balloon occlusion or stenting are preferablytried preoperatively.

4. Dissection and Resection after Permanent Balloon Occlusion of the

Internal Carotid ArteryIn patients in whom the tumor is adjacent to the carotid artery, the preoperative examination to determine whether the carotid artery has to be resected is a crucial and difficult task that can lead to false-negative and false-positive results. Carotid artery invasion is difficult to assess even at operation: often the tumor obscures a portion of the carotid artery or completely surrounds it; malignant tumors, by their infiltrative nature, do not allow for their separation from the ICA; manipulating vascular tumors can increase the difficulty, as bleeding impairs visualization.

When the carotid artery has been controlled by balloon occlusion these problems are lessened but not eliminated.

Dissection of the occluded ICA is started the cervical level; after isolation, the artery is ligated immediately after the proximal balloon; then dissection and separation from the tumor proceeds fromthe vertical petrosal segment until the junction between horizontal petrosal and lacerum segments; finally,

thanks to the presence of a balloon in the cavernous segment, the petrous portion of the artery is resected, possibly with a portion of tumor adherent to it, and sent for pathological examination . Indeed only after serial sections of the suspected arterial segment are made can a determination be made whether there has been vascular invasion.

Despite the lack of carotid wall infiltration, removal of these tumors and of the adventitia can significantly weaken the carotid wall and lead to blowout; therefore, PBO of the ICA should be strongly considered in skull base tumors with massive radiological involvement of the ICA.

5. Subadventitial Dissection afterReinforcement with Stenting

From a surgical point of view, preoperative stent insertion allows the skull base surgeon to perform subadventitial dissection of the ICA with a significant reduction of the surgical risk.

In the presence of an intraluminal stent, in fact, the surgeon is usually able to establish a cleavage plane reaching the external surface of the stent, so removing all the involved portion of the arterial wall. At the same time, the presence of the metallic net of the stent represents protection against accidental rupture; this is particularly true when working at the level of the carotid genu and the horizontal segment of the petrous ICA. In this area the surgical room and the mobility of the artery are reduced and direct control of the medial wall is particularly demanding, increasing the difficulty and the risk of surgery. The thickness of the struts of the stent, which determines its rigidity and its resistance to crushing, can offer different surgical sensations: although surgical dissection in the presence of thicker stents has seemed more comfortable, it has been possible without surgical problems even in the presence of softer stents.

https://www.youtube.com/watch?v=7tW3Ev9siCs – watch video of Prof. Mario sanna

-

Medication schedule associated with stenting into the internal carotid artery

Changes of anatomy of the internal carotid artery after stent insertion. One month after the stent insertion, the neointimal

layer is developed and subsequent subadventitial dissection can be safely performed.

Dissection usually starts at the cervical level, away from the tumor, where it easier to find the correct cleavage plane and proceed distally; the anteromedial wall of the artery is considered the most difficult to manipulate because direct visualization requires bony decompression and anterior displacement of the intrapetrous segment of the ICA. The unsolved surgical problem remains the medial wall of the ICA at the level of the anterior foramen lacerum, until now unreachable with the available surgical approaches.

The plane of dissection between the internal carotid artery and the overlying periosteum is best developed at the entrance of the artery into its canal.

C basal turn of the cochlea (promontory) , ICA internal carotid arteryP periosteum

a Intraoperative view of the balloon used to permanentlyocclude the internal carotid artery. b, c Schematic drawings showingthe permanent balloon occlusion of the internal carotid artery. MCA

middle cerebral artery. BA basilar artery. ACA anterior cerebral artery.OA ophthalmic artery.

a, b Schematic drawings showing the stent reinforcement ofthe internal carotid artery. MCA middle cerebral artery. BA basilar artery. ACA anterior cerebral artery. OA ophthalmic

artery.

JNA surgery by 4 corridors approach - by Dr. James K. Liu - I feel this 4 corridor is safest surgery for intracavernous & intracranial extension JNAs rather than removing only by nose. Orbitozygomatic transcavernous gives proximal & distal control of ICA . Endoscopic Caldwell-Luc ( Tranasmaxillary ) preserves Nose anatomy – see video https://www.youtube.com/watch?v=ekwOfEmHGWg&feature=youtu.be

JNA classification based on vascular supply to tumor – by Amit keshri

JNA selection of approach discussion

https://www.facebook.com/groups/347913135290330/permalink/575333442548297

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Mario sanna lateral skull base book

Sacrifice of the Internal Carotid Artery (Figs. 8.46−8.49) The internal carotid artery can be sacrificed in the rare cases in which the artery is markedly encased by the tumor with subsequent stenosis or in cases with fragile wall of the artery due to previous surgery or irradiation. A preoperative balloon occlusion test is mandatory. If the test shows that the artery can be safely sacrificed, a permanent balloon is left to close the artery (Figs. 8.46−8.49). In our early practice, carotid resection was performed more frequently; with time, we have adopted a less aggressive attitude for fear of long-term consequences.

Prof. Laligam Sekhar says - When the ICA is invaded or encased by tumor, two controversies continue to rage. 1. The first is whether one should attempt to

skeletonize the vessel by removing tumor or whether the vessel should be resected.

2. The second concerns the question of whether all patients should be revascularized, or only those whose collateral circulation is demonstrated tobe limited.

Whether or not the ICA should be left intactdepends on the surgeons attitude and the nature ofthe tumor. Benign tumors other than meningiomas(e.g. schwannoma, pituitary adenoma) may usuallybe dissected from the ICA. With meningiomas,however, encasement and narrowing of the ICAfrequently indicates that the vessel wall has been invaded by tumor. This has been conrmed by histologicalstudy of removed arteries [19]. Therefore,total resection often requires ICA resection. Ofcourse, the surgeon may choose to leave tumorbehind and treat it with radiosurgery. Generally,chordomas and chondrosarcomas can be dissectedfrom the ICA, but some require replacing the arterywith a bypass graft. With slowly growing malignanttumors such as adenoid cystic carcinomas, totaltumor removal requires resection of the ICA-CS.Furthermore, resecting and replacing the artery encasedwith tumor allows the surgeon to give the taskof preserving cranial nerves his full attention.

Should a revascularization procedure be performed in every patient where tumor resection creates jeopardy for the ICA, or only in those who fail preoperative balloon-occlusion testing? This is a hotly debated issue, but the occurrence of stroke even when excellent collateral circulation is present convinces us that a bypass should be performed every time tumor resection places the ICA at risk.

Our [ Prof. Laligam sekhar ] patients also undergo cerebral angiography.Collateral circulation and tolerance to temporaryocclusion is assessed by compressing the ipsilateral common carotid while injecting contrast material into the contralateral ICA and the dominant vertebral artery. We no longer perform balloon occlusion tests since we revascularize all patients in whom ICAresection or injury seems likely.

Videos of carotid injury & its management

• https://www.youtube.com/watch?v=deDNqRS4-OI

• https://youtu.be/HZ2j8BSRLzc

My understanding With the pretext " DON'T CROSS THE NERVES " in endoscopic skull base , anterior skull base surgeons trying to remove tumor lateral to parasellar carotid . But this don't cross the nerves won't stand in lateral transtemporal skull base or neurosurgical skull base . Since ages neurosurgeons and lateral skull base surgeons removing the tumor lateral to parasellar carotid by anterior medial & anterio-lateal & parkinson traiangle Or they don't hesitate to cut V2 & V3 . Moveover these lateral approaches have GREATEST control over the carotids . The remaining tumor medial to the parasellar carotid can be removed by endoscopic aproach [ combined approach – click http://www.slideshare.net/muralichandnallamothu/combined-approaches-of-skull-base-360 ]

If there is any rupture of parasellar carotid you can't even pass the stent also & it may occlude the opthalmic artery . But recently Covered stents which can be passed into parasellar carotid told to me by vascular neurosurgeon – This is a big boon to anterior skull base approach –Several seniors opinions has to be taken regarding longterm effects of these stents http://www.ncbi.nlm.nih.gov/pubmed/25415067 http://www.ncbi.nlm.nih.gov/pubmed/25790070 http://www.ncbi.nlm.nih.gov/pubmed/15337877 So to my understanding it is always better to have pterional approach exposure ready & then remove the parasellar tumor by endoscopic or combined especially in revison , fibrous & post-RT cases . If there is rupture of cavernous carotid , you can do SHUNT procedure by pterional exposure. If there is no cross circulation preoperatively even Pterional approach is risky.

This distal & proximal carotid control is called “ CAROTID LOCKING ” – possible only in Pterional approach whether it is Endoscopic pterional or Microscopic

pterional approach – Not at all possible in anterior skull base

If there is covered stunt or coiling migration or intentionally if we want to cross cranially the opthalmic artery we have to check whether there is anastamosis of external carotid artery [ ECA ]

to opthalmic artery [ OA ] by middle meningeal artery [ MMA ] - then only we have to block opthalmic artery - very important in parasellar tumors

Regarding anterior skull base when there is rupture of carotid only 2 options are

1. Covered stents 2. Clamping .

But recently Covered stents which can be passed into parasellar carotid told to me by vascular neurosurgeon – This is a big boon to anterior skull base approach –Several seniors opinions has to be taken regarding longterm effects of these stents

http://www.ncbi.nlm.nih.gov/pubmed/25415067 http://www.ncbi.nlm.nih.gov/pubmed/25790070 http://www.ncbi.nlm.nih.gov/pubmed/15337877

Management of Tumor - Bypass surgery or stenting and subsequent tumor surgery should be performed as a two-

staged procedure: once the blood flow to the brain is secured the tumor can be removed in a separate session.

Timing of the tumor resection with respect to bypass surgery is dependent on which vascularization procedure was indicated and performed. The greater the complexity time consuming, and demanding the bypass procedure is, the more likely the resection of the tumor is planned as second surgery. Location of the tumor and its complexity, especially with regard to its involvement to the ICA, are also taken into account. In principle, if two different surgical approaches have to be used, one for the bypass and another for the tumor resection, it is prudent to proceed in two stages. Once the vessel is secured and has been sacrificed, the resection of the tumor can be performed in a separate session. We believe that two separate sessions are prudent since both the flow replacement procedure by bypass creation and the tumor resection are inherently complex and demanding procedures.

http://neurosurgerynow.com/ - Dr.P. Sai Sudarshan sir told to me regarding covered stents which can be easily passed in parasellar carotids which previously I read/thought stents can't be passed

in parasellar carotid

Cavernous carotid foreign body by Medikeri's superspeciality ENT center – click

https://www.youtube.com/watch?v=ONC0OJBaUZs&feature=youtu.be

Discussion

Murali Chand Nallamothu BOT has to be done first & covered stent has to be passed if an iota of doubt is there & then only remove the foreign body .

Medikeri's superspeciality ENT center You cannot put a cover stent in the cavernous carotid boss. It just won't pass in a normal individual iteslf. Forget about it when there is a stick sitting inside. Besides we can't put any stent when there is a infected foreign body sitting there. The stent will act as a nidus of infection if we put one now.

Murali Chand Nallamothu Recently I spoke with interventional neurosurgeon who says covered stent can be passed in parasellar carotid . If not able to pass into parasellar carotid due to foreign body , then pterional approach has to be selected & prepared for shunts & combined approach has to be done . This is limitation of anterior skull base surgery . Satish Jain sir , Iype Cherian sir can clarify this case scenario management.

Medikeri's superspeciality ENT center Sir this case came to me after being seen by a neurosurgeons from an apex Institute where they dint want to do anything for him. The patient was roaming around for 2 months with them. That's why we took this decision that too after confirming good patency of ACOM & PCOM. I had explained to the patient about the grave risk but he was so fed up that he just wanted it to be done. Infact I delayed the procedure for hope of someone better than me probably a neurosurgeon performing it. Anyways it was done in good intent & due to lack of choice for the pt.

Iype Cherian I happened to see this remarkable case because Murali had invited me to see this. I read all the comments leading to why this procedure was done. Please understand that this procedure without carotid control was really pushing ones luck. What was the aim of this procedure when he already has a lost eye..? How did you know about the collateral circulation..? What does the DSA look like..? As a Neurosurgeon, everyone is not trained to do trans cavernous exposure of the carotid with proximal control. I would be showing this in the national skull base cadaver workshop, Jaipur in September if you would be interested...But doing it from the nose especially when you figure that the carotid is pierced by the foreign body is truly awesome !! ( I generally do not prefer calling someone stupid, because we all have been there... ) But my dear Medikeri, please dont ever repeat this...I am glad and I would consider it very lucky that the patient is doing fine. Next time ( if there is one) Do it with proximal control and get help form somebody who knows how to open the cranium..

• Rajinder Kumar The sequence of steps should have been..DSA, know status of ica , cross compression and check with bto if he tolerates the carotid clamping. If he does not tolerate then prior ECA ,MCA bypass first and then proceed with FB removal or remove it in angio suit with carotid catheter in place with stents ready. Mere presence of acom and p com does not mean anything in real practice. Even now the pseudoaneurysm is equally big challenge and need to follow above mentioned steps. However one the less both were lucky to have good outcome.

first thing we have to check BOT .• 1. If cross circulation is not there there is no point in going for surgery . So

direct Shunting has to be done . Surgery has to be done after 6 - 8 weeks .

• 2. If cross circulation good we can proceed for surgery with muscle patch & interventional radiologist ready . Even then there are higher chances of death .

• 3. So in revisions & post radiotherapy especially chordomas cases pre-op carotid coilling which completely occludes the carotid has to be done . Then you have to remove tumor . Even then in children it gives false sense of security . In adults we can safely remove tumor . Even then if the rent is more than 1.5 cm coilling may come out . But this is absolutely safe procedure

• I will write /update in detail in few days

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For better understanding of carotid injury PPT must read “ decision making of skull base” – click

http://www.slideshare.net/muralichandnallamothu/decision-making-between-anterior-skull-base-lateral-skull-base-57570902

For Other powerpoint presentatioins of “ Skull base 360° ”

I will update continuosly with date tag at the end as I am getting more & more information

click

www.skullbase360.in - you have to login to slideshare.net with Facebook account for downloading.