Shipo's triangle is considered in the topographic anatomy of the head. Its clinical significance is very high. It is necessary to know how this triangle is limited and what is its peculiarity (importance). We will consider the detailed structure and clinical significance of this organ in this article.
External view of the Shipo triangle
The structure of this triangle we will consider in this figure.
The mastoid process is numbered 1. This process is part of the temporal bone.
In front of the mastoid process is the external auditory meatus, it is indicated in the figure under number 2. After dissection of the soft tissues and detachment of the periosteum in the anterior-upper part of the region, you can see the "triangular platform", which was called Shipo.
Shipo triangle borders
Above the line, which is a continuation of the zygomatic arch, is indicated by number 3. In front, there is a vertical line drawn along the posterior edge of the external auditory canal. This line is numbered 4.
Behindand from below the crest of the mastoid process is indicated. This line is the third border of Shipo's trepanation triangle. This line is marked with the number 5.
Clinical significance of the triangle
In this formation, with purulent inflammation of the air cells (mastoiditis), you can perform trepanation of the mastoid process. This procedure is called an anthratomy.
This triangle is adjacent to formations that can be damaged during trepanation of the process.
What formations are adjacent to the triangle?
Surgical anatomy of the mastoid region of Shipo's triangle is such that the canal of the facial nerve is located in front of the triangle. This formation is indicated in the figure under the number 6.
Above is the middle cranial fossa, as well as the temporal lobe of the brain. These formations are numbered 7.
Behind and below - the sigmoid sinus of the dura mater, which is indicated by the number 8.
What is the meaning of the triangle?
Recall that the Shipo triangle is of great clinical importance. Where is this value needed? The answer is simple - in operative surgery (emergency surgery). In the event that the doctor needs to do an antrotomy, then he will need to get strictly into the Shipo triangle without damaging its borders.
If the operation is performed incorrectly, it is fraught with serious (fatal) consequences for the patient.
In the borders of the Shipo triangle there is a resonating depression, it is alsomastoid cave, this depression communicates with the entrance to the cave with the tympanic cavity of the middle ear. The mastoid depression, about 12 mm long and about 7 mm wide, is located at a depth of 1.5-2 cm of the bone element of the mastoid process. The size of the cave is variable due to the structure of the mastoid process (pneumatic, sclerotic or diploic).
The upper boundary, also known as the wall, isolates the cave with a typical head fossa. In its medial wall, there are 2 elevations, including the lateral semicircular canal, as well as the path of the external nerve. To the back wall of the cave, especially in brachycephals, since their mastoid process is poorly developed, because of this, the sigmoid venous sinus closely adjoins. But usually this sinus is separated from the cave itself by a very thick bone plate.
The history of the opening of the triangle
The Shipo triangle was discovered by a French neurosurgeon named Anthony Shipo in 1894. He discovered this structure and called it the optimal intervention site for mastoidectomy. His author's name for this formation was as follows - "attack site during mastoidectomy".
Subsequently, doctors described this area outwardly as follows: a smooth triangle, which is located on the mastoid process, namely on the temporal bone, near the external auditory canal. The area is limited to serious, clinically important formations. Constant trainings were held, where they taught doctors to carry out this procedure correctly, because the slightest mistake can result in disability oreven the death of the patient. But the question arises as to how such an operation was performed before. The answer is simple - it was performed according to the square method, of course, it was not so successful, and the wound healing time was very long. In addition, the surgical area was a quarter of the face.
