Blood vessels called arteries are used to transport blood from the heart to various body areas.
Blood that is moving away from the heart is referred to as having an antegrade blood flow. Blood that is traveling in a direction toward the heart is referred to as retrograde blood flow.
The term “subclavian steal syndrome” refers to a collection of symptoms and indicators that point to retrograde blood flow in an artery.
In some instances of subclavian steal syndrome, the vertebral artery receives retrograde blood flow. Blood is supplied to the neck and head via this artery, which runs along the human neck. Blood will be going away from the neck and head if you have subclavian steal syndrome of the vertebral artery.
The arteries that direct blood toward a person’s arm can be impacted by subclavian steal syndrome.
Subclavian steal syndrome is thought to affect between 0.6 percent and 6.4 percent of the general population, according to a 2019 assessment by experts.
In This Article...
Anterograde flow: what is it?
Anterograde 1 is defined as occurring or being carried out in the usual or forward direction of conduction or flow. Anterograde axonal transport, which contrasts with retrograde sense 1c, occurs along neural processes away from the cell body in letter a. (1)
What distinguishes antegrade flow from retrograde flow?
Anterograde transport is the movement of physiological substances in the direction of presynaptic terminals, whereas retrograde transport is the movement of physiological substances from the periphery back to the cell body.
Proteins and other chemicals made in the neurosome are transported to the nerve ends by the physiological process known as axonal transport, which involves the cytoskeleton. It is the procedure that involves the movement of materials from the cell body to the axonal terminal of neurons, to put it simply. Axons can carry information both ways. Anterograde and retrograde axonal transport fall into two groups based on the direction of the material flow. Materials are transferred from the periphery to the cell body in retrograde transport, whereas they are transported to the presynaptic terminals in anterograde transport. Additionally, while motor dyneins support retrograde transfer, motor kinesins support anterograde transport.
CONTENTS
1. Summary and Major Difference
2. Explain the term antegrade transport
3. Retrograde Transport: What Is It?
4. Comparative Advantages of Anterograde and Retrograde Transport
5. Anterograde vs. Retrograde Transport Side by Side Comparison in Tabular Format
6. Conclusion
Antegrade flow: is it typical?
- Describe the examination to the patient and get a complete and accurate medical history.
- Patient was lying on his back on the bed with his head resting on a pillow.
- Patient’s head should be slightly turned away from the side being scanned during the scan.
- Start by evaluating the vessels in B-Mode while maximizing variables like frequency, depth, gain, TGC, and focal zone.
ANGLE:
- Maintain the proper angle with the flow, NOT the vessel wall. It might not be in the middle of the vessel, and they aren’t necessarily the same.
- 60 degrees or less ( beyond 60degrees, error is exponentially increased)
- The ideal angle for least error and maximum doppler shift is 0 degrees. Although this is extremely rare, our human inter-observer error mistake is getting smaller as we go closer to 0 degrees.
- Accurate angle correction is achievable with contemporary equipment.
- Start in the proximal transverse direction and move distally to the bifurcation.
- Examine whether the path was convoluted and whether any plaque or intimal thickening was present.
- In the longitudinal plane, repeat.
- Utilize color to evaluate the vessel’s patency and the flow’s direction.
- Apply the “Heel/Toe” approach to the vessel to improve insonation, then use the color box and Doppler sample gate with the proper steering and angle adjustment.
- Peak systolic (PSV) and end diastolic (EDV) velocity measurements (EDV).
- Examine for pathology longitudinally and transversally.
- Determine where the ICA and ECA arteries originate. Small branches of the ECA exist (usually the thyroglossal artery). Additionally, the ECA often has a smaller diameter, a lateral rise, and a greater resistance waveform (ie lower diastolic flow than a normal ICA).
- You can also use “Temporal Tapping” to make sure you are looking at the ECA. This entails using a doppler sample of the ECA while lightly tapping the temporal artery, which is located about 1-2 cm anterior to the top of the ear. Reverberations in the trace that correspond to your tapping will be seen.
- A typical ICA won’t have any branches and typically has a waveform with reduced resistance.
- Calculate the ECA’s peak systolic and end diastolic velocities (PSV and EDV, respectively).
Despite being very uncommon, a “Carotid bulb tumour” might be a clinically important finding. This will take place outside of the vessels at the bifurcation and could extrinsically compress the carotid artery.
- First, in B-mode, and then with color doppler, follow the vessel. Keep an eye out for stenoses that have aliasing in the color doppler.
- Doppler samples should be taken at the proximal and distal segments as well as any other location where pathology or an altered waveform is found.
- Before calculating velocity, make sure you are angling correctly to the flow direction that the color doppler indicates. Importantly, the angle may not match the vessel’s direction.
- To see the vertebral artery, return to the CCA’s longitudinal plane and slant the beam posterolaterally.
- Make sure the PRF and gain are appropriate for these deeper, smaller boats. Low resistance flow should be present ( presence of forward diastolic flow).
- Verify whether the flow is antegrade, that is, heading toward the head, or retrograde (suggesting subclavian steal syndrome).
- Check the subclavian artery for a tight stenosis or occlusion that could cause subclavian steal syndrome if there is any indication of retrograde vertebral artery flow.
- The pathology is typically found between the vertebral origin and CCA origin.
- Similar to this, subclavian disease or CCA origin may be implicated in low systolic, high diastolic flow in the common carotid artery.
Always bear in mind the neck’s surrounding anatomy, as it may have clinical implications. For instance, thyroid pathology or swollen lymph nodes. If clinically necessary, formal follow-up examinations might be carried out along with brief documentation.
What exactly are anterograde and retrograde?
A form of memory loss known as amnesia affects your capacity to create, store, and retrieve memories. Memories that were generated prior to the beginning of amnesia are impacted by retrograde amnesia. After suffering a catastrophic brain injury, a person who develops retrograde amnesia may lose their ability to recall events from years or even decades before.
Damage to the memory-storage portions of the brain, in multiple brain regions, is what causes retrograde amnesia. A catastrophic injury, a severe sickness, a seizure or stroke, or a degenerative brain disease can all cause this kind of harm. Retrograde amnesia can be transient, persistent, or progressive, depending on the cause (getting worse over time).
Memory loss caused by retrograde amnesia typically includes information rather than abilities. For instance, a person may lose track of if they have a car, what kind it is, and when they got it, but they will still be able to drive.
Retrograde vs. anterograde amnesia
Anterograde amnesia affects the ability to form new memories following the beginning of amnesia. Retrograde amnesia makes it difficult for sufferers to recall events that occurred before to the commencement of the condition.
What distinguishes antegrade from retrograde motion?
I was quite interested to read the article titled “Laparoscopic anterograde cholecystectomy in acute cholecystitis.” In contrast to the word retrograde, which suggests moving backward or in the opposite direction from the flow, antegrade means moving or expanding forward. These terms are frequently used in medical terminology, for example, an endoscopic retrograde cholangiopancreatography is a cholangiogram performed from the ampulla into the bile duct, and a retrograde pyelogram is an intravasation of contrast from the urethra toward the kidneys. A retrograde method places the access vessel distal to the target lesion, whereas an antegrade technique confers with cannulation of the vessel proximal to the site of the lesion. This is also true when discussing endovascular vessel access.
Therefore, it would seem that the phrases antegrade and retrograde consider both the relative anatomical position and flow direction. It’s interesting to note that when the sphincter of Oddi is closed, the flow of bile is reversed from the bile duct into the cystic duct, but when the gallbladder is contracted and the sphincter of Oddi is relaxed, the flow of bile is in a forward direction. As a result, the concept of flow cannot be used to decide whether to perform an antegrade or retrograde cholecystectomy.
With time and improvements in surgical technique, the words antegrade and retrograde cholecystectomy have been developed. However, because the literature is so riddled with contradictions, it is exceedingly perplexing and contentious to use these terminology to describe the removal of the gallbladder. I cite Kelly et al., who defined a fundus first approach as a retrograde cholecystectomy. Neri et al., in contrast, refer to a fundus first strategy as antegrade.
It’s true that this idea was challenging to understand, yet antegrade or retrograde depends on the surgeon’s viewpoint and intended goal. The current method for cholecystectomy is a laparoscopic approach, with Calot’s triangle first being dissected and then the liver bed being cut up for fundic dissection. Theoretically, this is an antegrade dissection from the laparoscopic surgeon’s perspective, and the same is true for an open operation where the fundus is dissected then Calot’s triangle is dissected. Until the advent of laparoscopy in the 1980s, this language was likewise very contentious.
As was mentioned, there is confusion, and the nomenclature’s accuracy is called into question. It is suggested that the terminology be standardized. We suggest that the names “Fundus First” and “Calot’s First method for cholecystectomy” be changed to “antegrade” and “retrograde,” respectively.
What distinguishes anterograde from retrograde transportation?
Axonal transport can happen in two different directions, as shown in Figure 3(A): anterograde transport is when it happens from the cell body to the axon tip, and retrograde transport is when it happens from the axon tip back to the cell body. (B) Several chemicals are carried simultaneously along microtubules found inside axons.