What is channel opening in a hair transplant? Sapphire and steel tips, incision direction and depth

What is channel opening?

Channel opening means making, one by one, the small incisions in the recipient area where the grafts (small pieces of tissue carrying one or more hairs) will sit. After taking the grafts from the donor area, we place them in the thinning area; for a graft to settle into the skin, a small opening is first needed at that spot. This opening is called a channel. In medical terms, this step is also known as recipient site creation.

The channel is the slot the graft sits in. The angle at which the channel enters the skin and the direction it points in determine which way the hair placed there will grow. The distance between the channels determines the density, and their depth and width affect how well the graft will fit. A hair keeps growing in the direction in which it leaves the skin, and this direction does not change by itself after the transplant. That is why channel opening is one of the steps that call for the most care on the day of the procedure.

Channel opening is not a separate method but a step in a hair transplant: however the grafts are taken, the recipient area has to be prepared. We describe how FUE (the method in which grafts are taken one by one) works as a whole in our article What is an FUE hair transplant? Before opening the channels, we numb the recipient area with local anesthesia.

Which tips are used to open the channels?

The tools used to open channels all have the same goal: to make a clean channel that holds the graft without squeezing it, but without leaving a gap around it either. The difference between them lies in the material and shape of the tip.

The name “Sapphire FUE,” which you will often hear, does not describe a separate method either; it refers to FUE in which the channels are opened with a sapphire-tipped blade. The only thing that changes is the tip that opens the channel; the grafts are harvested and placed according to the same principles. We explain the details on the Sapphire FUE hair transplant page, and placement with an implanter pen on the DHI hair transplant page.

You may hear claims that a sapphire tip leaves fewer scars or speeds up healing. Only a few studies have compared sapphire and steel tips, and they are not strong enough to confirm these claims. That is why we do not present the material of the tip as an advantage in itself. What matters more than the material is opening each channel at the right size, angle, depth and spacing; and that depends on the planning and on the experience of the doctor performing the procedure.

Angle, direction and incision orientation: lengthwise or crosswise?

We open each channel so that it follows the angle and direction in which the natural hair in that area grows out. At the front hairline, the hairs leave the skin at a low angle, lying close to it; at the crown, the direction turns step by step around the whorl. We explain this pattern at the front hairline in our article on hairline design.

Besides the angle and direction, the line along which the incision runs in the skin is also a choice. There are two approaches:

• Lengthwise (sagittal) incision: The incision runs in the same direction as the hair grows out. Because hair at the front of the head grows forward, this incision runs from front to back. The hairs of a multi-hair graft sit in a row in the channel, one behind the other.
• Crosswise (coronal or lateral) incision: The incision runs at right angles to the direction the hair grows out; at the front of the head, it runs from ear to ear. This time, the hairs in the graft line up side by side.

Doctors who prefer crosswise incisions say this approach makes it easier to control the angle at which the hair grows out and lets the hairs in a graft fan out sideways to cover a wider area. Lengthwise incisions are also widely used, and some doctors prefer them in certain areas. There is no strong evidence that either approach gives better results for everyone. In some plans, both may be used, depending on the area.

The depth, width and spacing of the channels

The size of a channel should match the size of the graft that will sit in it. Narrower channels are opened for single-hair grafts, and slightly wider ones for multi-hair grafts. Because single-hair grafts are mostly used at the front hairline, the channels there are usually the finest.

Depth

The aim is for the graft to sit level with the surface of the skin. That is why we adjust the depth of the channel to the length of the grafts. If the depth does not match the graft, the following may happen:

• If the channel is shallower than the graft, the graft may stick up above the surface or pop out of place; after healing, small bumps may remain around the grafts.
• If the graft sits deeper than it should, it may sink below the surface of the skin; this can lead to small pits, ingrown hairs or small cysts.

Width

If the channel is narrower than the graft, the graft may be squeezed and crushed as it is placed; if it is wider, the graft may not sit firmly in place. That is why we choose the width of the tip to suit the size of the grafts.

Spacing and distribution

The distance between the channels determines how dense the recipient area will look. However, opening the channels very close together can affect the blood supply to the recipient area. That is why we decide how densely to open channels in an area in one session based on the condition of the skin. We explain the role density plays in planning in our article on how many grafts are needed.

We do not open the channels in straight rows but in a slightly irregular pattern, as in natural hair; hair lined up in rows draws attention. If you still have some of your own hair in the recipient area, we open the channels between these hairs, taking care not to damage their roots. Some of this hair may fall out temporarily in the weeks after the transplant (shock loss); some of the hairs that had already become thin may not grow back.

Who opens the channels?

In Turkey, only an authorized physician may carry out the channel-opening step of a hair transplant. Opening channels is a medical procedure that involves making incisions in the skin; for each channel, decisions are made about angle, direction, depth and spacing.

In our practice, too, a physician opens the channels. Based on the plan made before the procedure, the physician also decides which tip to use, the orientation of the incisions and how dense the channels will be. It is natural to ask, during the initial call or the examination, who will open the channels and which tip will be used.

What do we not know yet?

The general principles of channel opening have been known for a long time; however, some questions are still open:

• Sapphire or steel? Showing reliably whether the material of the tip has any effect on healing time, scarring or hair growth would take well-designed comparisons in which patients are randomly assigned to groups.
• Lengthwise or crosswise? How the orientation of the incision affects the blood supply to the recipient area is still debated; it has been suggested that crosswise incisions may cause less damage to blood vessels, but neither has been clearly shown to be better when it comes to how well grafts take hold.
• How dense in one session? How densely channels can be opened in an area in one session varies from person to person, depending on the condition of the skin; there is no measure that shows this limit precisely in advance.

What do we look at during the examination and planning?

We make most of the decisions about channel opening before the day of the procedure, during the examination and planning. Together, we look at:

• The size and location of the area to be transplanted
• The angle and direction in which your hair grows in and around this area, and the pattern of the whorl at the crown
• Whether you still have some of your own hair in the recipient area, and how much it has thinned
• The thickness and curl of your hair, and how many hairs the grafts in your donor area mostly carry
• Whether there is scar tissue in the recipient area from a previous procedure or another cause

Based on this information, we decide which tip to use, the orientation of the incisions, and the size and density of the channels. We make the final adjustment to depth and width on the day of the procedure, by looking at the grafts that have been harvested. We discuss the plan that suits you together during the examination.

In the days after the procedure, you may notice redness, mild swelling or scabbing in the recipient area; these are a normal part of healing, and how long they last varies from person to person. Follow the written instructions we give you for washing and aftercare.

Whether you are suitable for a hair transplant is determined during the examination, and results vary from person to person.