Fractures of the orbit

[1], [2], [3]

"Explosive" fracture of the bottom of the orbit

A “pure” orbit fracture does not affect its edges, while with a “mixed” fracture, the edges of the orbit and the adjacent bones of the face suffer. An “explosive” fracture of the bottom of the orbit is usually caused by a sudden increase in intra-orbital pressure when struck by an object larger than 5 cm in diameter, for example, with a fist or a tennis ball. Due to the fact that the lateral wall and the roof of the orbit usually withstand a similar effect, the fracture of the orbit is often involved in the fracture, along with the thin bones that form the walls of the lower orbital fissure. In some cases, the medial wall of the orbit also breaks. Clinical manifestations vary depending on the severity of the injury and the time interval between injury and examination.

Symptoms of an explosive fracture of the bottom of the orbit

1. Periocular signs: chemosis, edema, and subcutaneous emphysema of varying degrees.
2. Anesthesia of the region of the innervation of the infraorbital nerve affects the lower eyelid, cheek, back of the nose, upper eyelid, upper teeth and gums, since an "explosive" fracture often affects the walls of the infraorbital fissure.
3. Diplopia may be due to one of the following mechanisms:
   • Hemorrhage and edema cause the orbital tissue to tighten between the lower straight, inferior oblique muscles and the periosteum, which limits the mobility of the eyeball. Eye mobility usually improves after resolution of hemorrhage and edema.
   • Mechanical infringement in the area of the fracture of the lower rectus or inferior oblique muscle or adjacent connective and adipose tissue. Diplopia is usually seen when looking both up and down (double diplopia). In these cases, the traction test and the differential test of the reposition of the eyeball are positive. Diplopia may subsequently decrease if it was caused mainly by the incarceration of connective tissue and fiber, but usually persists with the involvement of the muscles in the fracture.
   • Direct injury of extraocular muscles in combination with a negative traction test. Muscle fibers usually regenerate, and after 2 months normal function is restored.
4. Enophthalmos occurs in severe fractures, although it usually appears several days after the onset of edema resolution. Without surgery, enophthalmos can increase up to 6 months due to post-traumatic degeneration and tissue fibrosis.
5. Ocular lesions (hyphema, angle recession, retinal detachment) are usually uncharacteristic, but they should be excluded with careful examination of the slit lamp and ophthalmoscopy.

Diagnosis of an explosive fracture of the bottom of the orbit

1. CT in frontal projection is especially necessary in assessing the length of the fracture, as well as to determine the nature of the density of soft tissue in the maxillary sinus, which can be filled with orbital fat, extraocular muscles, hematoma, or polypamp unrelated to injury.
2. The Hess test is useful in assessing and controlling the dynamics of diplopia.
3. The binocular field of view can be assessed at the perimeter of Lister or Golgmann.

Treatment of an explosive orbital fracture

Initially conservative and includes antibiotics if the fracture affects the maxillary sinus.

The patient should be informed about the undesirability of blowing his nose.

The subsequent is aimed at preventing permanent vertical diplopia and / or cosmetically unacceptable anophthalmos. There are three factors that determine the risk of these complications: the size of the fracture, the hernia of the orbital contents in the maxillary sinus, and the pinching of the muscles. Although there may be some confusion of symptoms. Most fractures fall into one of the following categories:

• Small cracks without the formation of a hernia do not require treatment, because the risk of complications is negligible.
• Fractures affecting less than half the bottom of the orbit, with small hernias or their absence, the positive dynamics of diplopia also do not require treatment until anophthalmos more than 2 mm appears.
• Fractures that spread to half or more of the orbital bottom area, with infringement of the orbital contents and permanent diplopia in a straight position, should be operated for 2 weeks. If surgery is delayed, the results will be less effective due to the development of fibrotic changes in the orbit.

Surgical treatment technique

• transconjunctival or subciliary skin incision;
• the periosteum is separated and raised from the bottom of the orbit, all the restrained orbital contents are extracted from the sinus;
• the defect of the bottom of the orbit is restored using a synthetic material such as supramid, silicone, or Teflon;
• overcoat sewn.

CT shows a postoperative condition after the restoration of an “explosive” fracture on the right using a plastic implant.

[4], [5], [6], [7], [8], [9], [10], [11]

"Explosive" fracture of the medial wall

Most of the fractures of the medial wall of the orbit are combined with fractures of the bottom of the orbit. Isolated fractures are rare.

Symptoms of a fracture of the medial wall

• Periorbital subcutaneous emphysema, which usually develops during blowing your nose. Due to the possibility of infection of the orbit with the contents of the sinus, one should strive to exclude such a method of emptying the nasal cavity.
• Changes in eye mobility, including adduction and abduction, if the medial rectus muscle is strangulated at the fracture.

Treatment includes the release of strangulated tissue and the restoration of bone defect.

[12]

Orbit roof fracture

Ophthalmologists rarely encounter fractures of the orbital roof. Isolated fractures caused by minor injuries, such as falling on a sharp object, as well as a blow to the eyebrow or forehead, are more common in young children. Complicated fractures. Caused by severe trauma, combined with the displacement of the orbital rim, as well as damage to other craniofacial bones, are most common in adults.

A fracture of the orbital roof is manifested in a few hours by hematoma and periokular chemosis, which can spread to the opposite side.

Extensive bone defects with downward displacement of fragments usually require reconstructive surgical procedures.

[13], [14], [15]

Fracture of the lateral wall of the orbit

Ophthalmologists rarely experience acute fractures of the lateral wall. Since the outer wall of the orbit is more durable than others, its fracture is usually combined with extensive facial injuries.

Symptoms of the lateral wall fracture

• The displacement of the eyeball is axial or downward.
• Large fractures can be combined with a pulsation of the eyeball, which is not associated with noise, due to the transmission of pulsation of cerebrospinal fluid, which is best detected by applanation tonometry.

Lateral wall fracture treatment

Small fractures may not require treatment, but it is important to observe the patient to rule out the possibility of liquorrhea, which can lead to meningitis.

[16], [17]