Circular Knife

Apex Arachnoid Knives: Designed by Neurosurgeons for Use by Neurosurgeons

2.2 mm circular blade with a 0.9 mm tip width and 320° cutting edge

Developing Planes: Facilitates the flow of an operation by permitting the transition from sharp to blunt dissection.

The most robust of the four knives.
If presented with plane of arachnoid in a very small space the circular knife can be used to make a small hole prior to using the Backcutting Knife to more safely strip away tissue.
Surgeons use a rotating motion to move the leading edge across the surface either in a horizontal or vertical orientation. While using the knives in this manner, a surgeon can part the very top surface of tissue without penetrating deeper than the curved blade edge.
Because the circumference is sharp 320° around, the inside angle on either side can be used to catch and pull tissue.
The circular knife can also be used for heavier dissection in some of the most delicate spinal applications.

(Click image to enlarge) Some surgeons are comfortable holding the smooth tapered distal portion of the handle and “choking up” on the knife during surgery near the surface of the brain or operating with wrist rests. But the primary purpose of the long 4.0" tapered distal shaft is to permit precise delicate controlled microsurgery in any deep seated location.

(Click image to enlarge) The shorter handle length permits surgeons to rest their hands on the patient and maintain meticulous control at superficial depths. If a surgeon is working on a deep seated lesion, this length will be effective for opening the Sylvian or interhemispheric fissure before switching to a longer instrument.

(Click image to enlarge) The bayonet handle was created for the 30% of neurosurgeons who only use bayoneted instruments. While the bayonet handle provides better visibility, there is a trade-off in that the handle can’t be rotated to change the orientation of the blade as can be done with a straight instrument.

(Click image to enlarge) The short bayonet handles provide an instrument with facility and control for neurosurgeons operating at more superficial depths. The 1.0" and 2.0" distal shaft lengths enable surgeons to change their depth without changing their operative style or forgoing the stability gained by resting their hands on the patient. These instrument options are more effective for a large number of common cerebrovascular and skull base approaches.

(Click image to enlarge) The extended bayonet handle with its 6.0" tapered distal shaft is intended for precise surgery in relatively inaccessible regions of the brain, where the standard bayonet would not be usable. The 0.25" diameter proximal portion of the handle is shortened from 4.0" to 3.0" to keep the overall length usable in the field and to facilitate approach to more inaccessible lesions.