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Year : 2010  |  Volume : 4  |  Issue : 2  |  Page : 57-63  

Postgraduate educational pictorial review: Ultrasound-guided vascular access

Department of Anesthesiology and Operating Rooms, King Fahad Medical City, Riyadh, Saudi Arabia

Date of Web Publication3-Dec-2010

Correspondence Address:
Altaf Bukhari
Department of Anesthesiology and Operating Rooms, King Fahad Medical City, P. O. Box: 59046, Riyadh: 11525
Saudi Arabia
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0259-1162.73507

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Over the last few years the role of ultrasound has steadily increased and has now an established role in anesthesia and critical care. The various applications of this technology in this field include ultrasound-guided insertion of central lines (internal jugular, subclavian, axillary, femoral) and peripheral venous catheters, arterial line insertion, regional blocks etc. The simple reason of using this technology is "You believe what you see". In this text we will mainly focus on central line, peripheral venous placement and arterial blood flow patterns under ultrasound guidance.In our institution at KFMC, internal jugular vein cannulation is preferred to cannulation of the subclavian vein because of the higher incidence of pneumothorax and subclavian artery puncture associated with the later. The incidence of carotid artery puncture is higher in children younger than five years than in older children during this procedure. The use of ultrasonography has been shown to increase the success rate and decrease the incidence of complications associated with IJV cannulation in adults.
We will go through a stepwise approach in identifying and confirming the required blood vessels for ultrasound-guided cannulation using B-mode (2D), color flow doppler and Pulse Wave Doppler

Keywords: Ultrasound aided, vascular access, internal jugular vein, femoral vein, peripheral vein

How to cite this article:
Bukhari A, Kitaba A, Koudera S. Postgraduate educational pictorial review: Ultrasound-guided vascular access. Anesth Essays Res 2010;4:57-63

How to cite this URL:
Bukhari A, Kitaba A, Koudera S. Postgraduate educational pictorial review: Ultrasound-guided vascular access. Anesth Essays Res [serial online] 2010 [cited 2022 Dec 6];4:57-63. Available from:

   Introduction Top

Traditionally, we have been using blind techniques to secure access to central veins like internal jugular, femoral, subclavian etc., and have proved efficacious in most of the cases. [1] The basis of successful cannulation relies on knowledge of surface anatomy and experience wherein anatomic homogeneity is assumed and does not account for the possibility of thrombosis, and depends on correct discernment of the relationship among multiple anatomic landmarks. [2] Even for an experienced operator, there is an incidence of failure and complications related to malposition of the needle during cannulation. It is not possible even for an experienced operator to perform a procedure accurately if the anatomy is aberrant. It is simply that if we can identify the anatomy with ultrasound, then it is more easier to successfully cannulate the vessels.

   A Case Scenario Top

A 55 year old lady diabetic, hypertensive, coronary artery disease on medical treatment and dialysis dependent end stage renal disease, is admitted in coronary care unit (CCU) being treated for left ventricular failure (LVF). The examination reveals the patient to be morbidly obese with extremely short neck, on high flow oxygen therapy being nursed in sitting position, on conservative treatment for LVF. The patient needs a dialysis catheter for hemodialysis. Multiple puncture marks are seen on both sides of the neck, subclavian as well as at femoral sites but all the attempts of catheter insertion by the landmark technique have failed. The anesthesia department is called for the help. Looking at the morbidly obese patient who is sick and multiple attempts at catheter insertion already tried by many experienced clinicians in CCU, the decision is taken to place the dialysis catheter under ultrasound guidance. A high frequency linear probe with Sonosite is used to place a 9F dialysis catheter in the right IJV of the patient under local anesthesia in the first attempt and the whole process takes less than 10min. Post procedure a portable chest x-ray is performed and the correct placement of the catheter is confirmed. The patient is comfortable and thanks the team for not giving her multiple pricks for the same procedure.

In our practice we are faced with a multitude of similar cases where vascular access is difficult and the patients are sick who need immediate circulatory resuscitation. Ultrasound in these situations is helpful and even lifesaving.

Types of Probes and Principles of Imaging Vessels for Cannulation

There are usually two types of probes: [3]

  1. Linear array probe and
  2. Phased array probe.
Linear Array Probes

These high frequency probes are the commonest probes being used for peripheral vascular and small parts examination. They are good for both color as well as pulse doppler examinations. It is a better choice than a phased array transducer for vessel cannulation. A linear array transducer is used to measure flow with Doppler in parallel vessels, and assumes an insonation angle of 60° [Figure 1]. The usual consideration is to choose the highest frequency transducer that will provide imaging for the depth of vessel that you are attempting to cannulate. For most vessels, best imaging is obtained using high frequency transducers (such as 10 to 15MHz). These transducers, however, have the limitation of providing good imaging down to only about four centimeters.
Figure 1: A linear array probe

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Curved Linear Array Probe

These are low frequency probes but have a higher penetration and are used for imaging deeper vessels like, femoral veins in an obese patient, subclavian vessels, distal superficial femoral veins, calf veins etc [Figure 2]. These transducers are also used for abdominal, obstetric and pelvic examination as well. Although the resolution of the images is not as good as linear array probes but have a greater penetrability which is important for the above mentioned vessels. These probes are not good for Doppler assessment.
Figure 2: Curved linear array probe

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Cardiac Phased Array Probe

Although this type of probe is usually used for cardiac imaging and lung ultrasound to see and quantify pleural effusion, but can also be used for ultrasound guided vascular access especially internal jugular vein, in emergency situations [Figure 3], if high frequency linear array probe is not available. In that situation the depth must be decreased to the maximum possible.
Figure 3: 5 MHz cardiac phased array probe

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Following are the tips to obtain good imaging:

  1. Select the most appropriate transducer
  2. Position the patient to provide the best access to the vessel you are going to cannulate
  3. Have ultrasound gel and a marking pen at hand
  4. Apply enough gel
  5. Optimize the machine gain and depth settings; for most vessels a depth of three to five centimeters is ideal. This is important while imaging of vessel some distance away from the ultrasound screen
  6. Apply light pressure, as the veins are compressible, may obliterate the structure that we are trying to image
  7. While performing a Doppler examination, locate the vessel in transverse section first and then rotate the probe to image in the longitudinal section. This is particularly important when imaging small vessels such as the radial artery, as it is difficult to find in the longitudinal section
  8. Whilst we are getting used to ultrasound imaging, it is easier to find the vessel and mark its location and then perform the actual procedure without ultrasound. This is also quicker than directly imaging the vessel while inserting the needle. But if we are performing the procedure by the direct technique then the probe must be in a sterile sheath and we need to hold the probe in one hand and insert the needle with the other
  9. Point-of-care ultrasound machines are available with different types of transducers. These machines are portable, can be used anywhere in the hospital and have the advantage of being able to be placed closer to the operator performing the procedure. The Sonosite Turbo shown below is a point-of-care ultrasound machine widely used nowadays for vascular access [Figure 4].
Figure 4: The Sonosite Turbo

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   Indirect Technique (Find and mark) Top

In this technique, we locate the vessel with ultrasound and mark its direction, noting the depth from the skin surface. We then put away the ultrasound machine and perform the vessel cannulation in the usual manner. The technique is to hold the probe in one hand and the marking pen in the other. Move the probe in transverse section to center the vessel in the middle of the screen. This corresponds to the vessel overlying the middle of the transducer. Then place and mark distally and proximally so that the direction of the vessel is clearly outlined. Then note where the vessel is the largest and place a mark in the transverse plane, and finally note how deep the vessel is and its relation to other structures.

Ultrasound guidance by the indirect method was shown to have no effect on the rate of complications or failures. [4]

   Direct Vision Approach (Real Time Ultrasound Guidance) Top

The usual technique is to place the probe in a sterile sheath, use sterile gel and perform the vessel cannulation under direct ultrasound guidance. [5] This technique is definitely more difficult to do initially, but when we get used to holding the probe and looking at the vessels, it is certainly more accurate. The things we have to get used to is, firstly to hold the probe over the site that we will cannulate and secondly, that we cannulate looking at the ultrasound machine rather than at the skin overlying the vessel. Finally, the needle is not shown on ultrasound as a needle, but as a point of ultrasound dropout that indents the tissues as it passes through them. We produce jiggling while passing through the tissues. Jiggling is producing the movement of the tissue through which the needle is passing. We can generally see the depth and direction of the needle and this allows us to change the angle that we pass the needle as it approaches the vessel. The veins are very compressible, and the needle will commonly indent the vein before it punctures it. We should pass the needle slowly otherwise it will easily transfix the vein. Once we are confident with the technique, we will be more successful in cannulating difficult vessels with this technique than with the indirect technique. The visualization of the vein can be achieved either by a short-axis or a long-axis approach. [5] For the short-axis approach, the vessel is identified in the transverse plane and centered under the transducer. The midpoint of the transducer then becomes a reference point for insertion of the needle. The needle is inserted at a 45° angle to the transducer. As the needle is advanced, the tip is visualized as it approaches the anterior wall of the vessel. After contacting the anterior wall of the vessel, further insertion of the needle will cause posterior displacement of the vessel wall. A flash of blood in the syringe signifies that the needle has entered the vessel. At this point, the transducer can be set aside and the rest of the procedure performed normally. In contrast, the long-axis approach identifies the vessel in its long axis and involves lining up the transducer over the greatest anterior-posterior diameter of the vessel. The needle is then inserted through the skin just off one end of the transducer in a plane that is in line with the long axis of the transducer and at an approximate 30° angle to the skin surface. As the needle is advanced, its progress through the subcutaneous tissue is monitored in real time on the ultrasound screen. After the needle has punctured the anterior wall of the vessel and a flash of blood is apparent in the syringe, the transducer can be set aside and the rest of the procedure completed normally, although there is no statistically significant difference in terms of mean difficulty, number of skin breaks and mean number of needle redirections. [6]

Imaging of the Internal Jugular Vein

Many approaches to cannulation of the internal jugular vein (IJV) have been described but, we will follow the usual and the simpler approach for its cannulation under ultrasound. When we use ultrasound, we will notice that the IJV lies anterior and lateral to the carotid artery (CA) in the middle portion. It may completely overlie the CA proximally or distally. The amount that the vein overlies the artery is very variable. In 1991, Denys and Uretsky] reported a series of 200 patients who underwent IJV cannulation in the cardiac catheterization laboratory, coronary care unit (CCU) and intensive care unit (ICU) and found anatomic anomalies of the IJV (small diameter, unresponsiveness to Valsalva maneuver and unexpected lateral or medial displacement) in 8% of patients. [7] Troianos et al. reported the largest case series for determining the anatomic relationship between the IJV and CA. Among 1009 patients admitted for surgery, 54% had an IJV overlying the CA, rather than coursing it laterally, as expected. This anomalous anatomy might predispose the patients to arterial punctures if the needle traversed the IJV. [8] Such evidence makes ultrasound guidance all the more important in patients with such anatomy. The second thing we will find is that the vein is very easy to compress with light pressure. When palpating the CA, the vein is completely squashed and obliterated. All the modalities including B-mode (2D) [Figure 5] color flow doppler (CFD) [Figure 6] and pulsed wave Doppler (PWD) [Figure 7] can be used to differentiate IJV from common carotid artery (CCA) [Figure 8]. Use of PWD produces typical arterial waveform when the cursor is placed on the CCA and a continuous venous waveform of venous flow when cursor is placed on IJV. In most instances, the collapsibility of the IJV seen on B-mode is sufficient to visualize and confirm its presence but the other modalities like CFD and PWD may be sometimes used to make the diagnosis sure. The short axis approach is most often used for the needle insertion but the long axis approach can be used as well. The IJV is actually compressed completely by the needle before the vessel is penetrated. The needle must be advanced a little deeper and then retracted slightly to be positioned in the center of the lumen. Once the flash of blood is seen in the needle and then the syringe and free flow confirmed, the transducer is set aside to complete the line insertion in usual manner.

But in certain situations, like thrombosis of the vessels where the collapsibility of the vein may not be sufficient to differentiate IJV from the CCA, CFD [Figure 6] can be helpful by confirming arterial flow of the CCA. The blood flow will be shown as color spurting with every cardiac cycle when arterial and will be continuous type when venous. The color whether red or blue doesn't mean to be arterial or venous, it just depicts the flow of blood towards or away from the transducer. If the direction of the blood flow is towards the ultrasound transducer the color of the jet will be red and if it is away from the transducer the color shown will be blue.
Figure 5: B-Mode (2D) of internal jugular vein (IJV) and right common carotid artery (RCCA) at the level of cricoid cartilage

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Figure 6: Color flow doppler (CFD) of internal jugular vein (IJV) and common carotid artery (CCA) in its transverse view.

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Figure 7: Pulsed wave doppler of the right internal jugular vein (IJV) at the level of cricoid cartilage

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Figure 8: PWD of the common carotid artery (CCA)

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The other method to differentiate between Carotid artery and the IJV or any other artery and the vein is Pulsed Wave Doppler (PWD). The venous flow in the IJV will be seen as continuous type [Figure 7] while as the PWD of the carotid artery is seen to be pulsatile with clear systolic peak, a dicrotic notch and a diastolic wave [Figure 8].

In our centre, we cannulated the IJV in about 70 patients since 2008 with expectedly difficult or difficult vascular access. Sixty nine out of 70 patients were successfully cannulated under ultrasound guidance. Only one patient couldn't be cannulated because the IJV was not properly visible on both sides. Vascular ultrasound performed by the radiology department confirmed that both IJVs were thrombosed and blocked. We have started using ultrasound guidance for the difficult vascular access in pediatric population as well.

Although, we don't have a clear evidence to show the exact time taken to improve the technique in ultrasound users in performing vessel cannulation but there is evidence to show that the use of ultrasound guided vessel cannulation decreases the mean time to successful cannualtion by almost 70 seconds (P value<0.02). [9]

Imaging of the Femoral Vessels

In medical school, we learnt the relationship between the vein, artery and nerve in the femoral region as "VAN" which denotes Vein, Artery and Nerve from medial to lateral. These structures are easily identified with ultrasound and it is soon apparent that their location is not always as easy as what is taught in medical school. The major difference between the neck and the groin is the depth that the vessels exist, particularly in obese patients. Modern study of the FV has discovered variations from the generally accepted anatomy. Reviewing CT scans of the pelvis in 100 patients, Baum et al. [10] discovered that a portion of the FV and the femoral artery overlaps in the anteroposterior plane 65% of the time. A subsequent study, [11] which used ultrasound in 50 ICU patients confirmed this finding: ''in most patients there was overlap of the artery over the vein far closer to the inguinal ligament than conventional anatomical textbooks would indicate'' It is easiest to locate the structures by placing the probe in the transverse plane, depth settings may need to be increased to five or more centimeters in obese patients. The internal jugular vein typically is 1-2 cm deep whereas the femoral artery and veins are typically 2-4cm cm deep. A 7.5-MHz phased array probe is used to locate large vessels, in obese patients and is not good for Doppler assessment. The veins do not typically lie next to the artery, but may overlap and may be superficial or deep to the artery. The indirect approach is generally sufficient for cannulation of the femoral vessels. However, visualizing the vessels and cannulating under real-time ultrasound guidance can be beneficial in situation where the chances of hematoma formation are more, like, coagulopathy etc. [Figure 9].
Figure 9: B-mode of the femoral vein and artery in its transverse section

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Imaging of the Radial/Ulnar Artery

Imaging of the peripheral arteries is done either to help cannulating them in difficult circumstances or to see if it is a diseased vessel. The radial artery is simply a small peripheral artery, and this section applies to any peripheral artery that we may wish to identify the patency. The radial artery is a special instance, because it communicates with the ulnar artery to supply the hand. High-frequency linear array transducers can image the radial and ulnar arteries and indeed may image the vessels of the hand.

These following techniques can help us determine patency of the vessels:

Two-dimensional examination

Simply place the transducer in the transverse plane and image along the length of the vessel looking for narrowing. The important thing to remember is that the vessel should decrease in size as it travels more distally and if we identify a segment of the vessel smaller than the distal size then there is probably a stenosis [Figure 10].
Figure 10: 2D (B-mode) in transverse plane of radial artery

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Color Flow Doppler

We will need to image in the longitudinal plane and apply Color Flow Doppler (CFD) to the vessel [Figure 11]. Either use the vascular preset function of the ultrasound machine or reduce the depth to 2 to 3 cm and reduce color scale to about 15-20 cm/s. Non-turbulent flow will be presented as red and blue according to the direction the blood is flowing. At that point of transition (i.e., when the flow is 90° to the transducer), we will see a meeting of blue and red colors. This represents a normal or non-turbulent flow. As with all Doppler, as a stenosis increases, the velocity of blood through the stenosis will accelerate leading to a mosaic pattern. If we see evidence of turbulent flow then we must strongly suspect that a stenosis exists.
Figure 11: Showing the PWD and Color Flow Doppler (CFD) of the radial artery

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Pulsed wave Doppler

Place the pulsed wave cursor in the vessel and select the spectral display [Figure 11]. With linear array transducers, it is assumed that the insonation angle is 60°, which is automatically included in the spectral display. When flow is low such as a patient at rest with cold hands, the Doppler signal tends to be a small systolic wave only. When flow increases such as after arterial occlusion or exercise, flow will occur in both systole and the diastole. When there is retrograde flow, it would suggest a proximal obstruction with flow being supplied from the ulnar artery.

In case of cannulation of the artery the same principle of transducer placement and needle puncture will be followed except that arteries are not collapsible, therefore the wall movement during systole and diastole should be seen on B-mode and CFD and PWD will have to be used frequently.

Imaging of the Arm Veins for Peripheral Line Insertion

Ultrasound offers a potential alternative to central venous access, surgical cutdowns, and blind, deep brachial vein catheterization for patients who need simple intravenous access but have no palpable or visible peripheral veins.

Studies of peripherally inserted central venous catheter lines have shown that real-time ultrasound guidance is safe and successful in adult [12],[13] and pediatric populations [14] The basic technique of using ultrasound is same as has been described before. B-mode, CFD and PWD, showing a continuous type of flow [Figure 12] can be used to confirm and differentiate vein from the artery which is showing a biphasic flow [Figure 13].
Figure12: CFD and PWD of the Brachial vein

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Figure 13: PWD of Brachial artery demonstrating a biphasic arterial flow pattern

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We can either use ultrasound to find the vein and mark its location or, directly visualize the vein as we are inserting the needle. The technique is useful when we are placing the catheter in veins proximal to the antecubital fossa, as they are often deeper under the skin than they are in the forearm. It is useful to use a very light pressure and lots of gel. Even slight pressure can compress the vein and make it difficult to visualize or cannulate it. Set the depth to one or two centimeters depending on the machine, and place the vein in the middle of the screen. This corresponds to the middle of the transducer so that we know where to insert the needle point. The veins are usually very superficial and will indent as the needle touches them. Insert the needle slowly, then watch the vein indent before the needle punctures the vein. Once you see the vein resume a round shape after the needle has indented it, then we know that the needle tip lies in the vein. At this point put down the transducer probe and aspirate on the needle to confirm placement. The rest of the technique is usually performed with a Seldinger approach.

This article entitled, Postgraduate educational pictorial review: Ultrasound-guided vascular access, has been prepared to help the postgraduate student community of anesthesia as well as critical care to generate interest and improve understanding of ultrasound guided vascular access. This tool especially gets importance when blind techniques of securing vascular access fail. In this article we have introduced all the modalities including B-mode, color doppler and pulsed wave doppler to differentiate between vein and artery which is an addition for understanding and confirmation of the right vessels to be cannulated. Most of the reviews of ultrasound guided vascular access include only B-mode for vessel differentiation.

Since ultrasound guided vascular access has been recently launched in our department we have not been able to conduct systematic research in this field until now, therefore the article lacks in enough published data from our unit which we believe is a demerit as for as this article is concerned.

   Acknowledgment Top

I acknowledge the continuous support of Mr. Mohammed Al Saadi, ultrasound supervisor, Dr. Nageeb, Department of Radiology regarding the training and Mr. Venu Madhav and his team of cardiac anesthesia technologists for continuous assistance. I also acknowledge the support of Prof. Mohammad Takrouri of the Department of Anesthesiology and Operating rooms at KFMC for preparation of this text. It was part of the workshop at The First International Neuroanesthesia Symposium at KFMC in Kingdom of Saudi Arabia from April 22-23, 2008.

   References Top

1.Parsa MH, Tabora F. Central venous access in critically ill patients in the emergency department. Emerg Med Clin North Am 1986;4:709-44.  Back to cited text no. 1
2.Tripathi M, Tripathi M. Subclavian vein cannulation: An approach with definite landmarks. Ann Thorac Surg 1996;61:238-40.  Back to cited text no. 2
3.Resnick JR, Cydulka R, Jones R. Comparison of two transducers for ultrasound-guided vascular access in long axis. J Emerg Med 2007;33:273-6.  Back to cited text no. 3
4.Mansfield PF, Hohn DC, Fornage BD, Gregurich MA, Ota DM. Complications and failures of subclavian-vein catheterization. N Engl J Med 1994;331:1735-8.  Back to cited text no. 4
5.Abboud PA, Kendall JL. Ultrasound guidance for vascular access. Emerg Med Clin North Am 2004;22:749-73.  Back to cited text no. 5
6.Blaivas M, Brannam L, Fernandez E. Short-axis versus long-axis approaches for teaching ultrasound-guided vascular access on a new inanimate model. Acad Emerg Med 2003;10:1307-11.  Back to cited text no. 6
7.Denys BG, Uretsky BF. Anatomical variations of internal jugular vein location: Impact on central venous access. Crit Care Med 1991;19:1516-9.  Back to cited text no. 7
8.Troianos CA, Kuwik RJ, Pasqual JR, Lim AJ, Odasso DP. Internal jugular vein and carotid artery anatomic relation as determined by ultrasonography. Anesthesiology 1996;85:43-8.  Back to cited text no. 8
9.Hind D, Calvert N, McWilliams R, Davidson A, Paisley S, Beverley C, et al. Ultrasonic locating devices for central venous cannulation: meta-analysis. BMJ 2003;327:361-7.  Back to cited text no. 9
10.Baum PA, Matsumoto AH, Teitelbaum GP, Zuuribier RA, Barth KH. Anatomic relationship between the common femoral artery and vein: CT evaluation and clinical significance. Radiology 1989;173:775-7.  Back to cited text no. 10
11.Highes P, Scott C, Bodenham A. Ultrasonography of the femoral veins in the groin: Implications for vascular access. Anesthesia 2000;55:1198-202.  Back to cited text no. 11
12.Sofocleous CT, Schur I, Cooper SG, Quintas JC, Brody L, Shelin R. Sonographically guided placement of peripherally inserted central venous catheters: Review of 355 procedures. AJR Am J Roentgenol 1998;170:1613-6.  Back to cited text no. 12
13.Chrisman HB, Omary RA, Nemcek AA, Ryu RK, Saker MB, Vogelzang RL. Peripherally inserted central venous catheters: Guidance with the use of US versus venography in 2650 patients. J Vasc Interv Radiol 1999;10:473-5.  Back to cited text no. 13
14.Donaldson JS, Morello FP, Junewick JJ, O'Donovan JC, Lim-Dunham J. Peripherally inserted central venous catheters: US-guided vascular access in pediatric patients. Radiology 1995;197:542-4.  Back to cited text no. 14


  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10], [Figure 11], [Figure 12], [Figure 13]

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