Penetrating injuries to the orbit.

Although penetrating orbital wounds are an uncommon entity they are often associated with vision and life-threatening complications. By careful attention to the history and physical signs of the injured patient and the use of modern computed tomography (CT) scan imaging, the physician will be better able to make an accurate analysis and prognosis of the problem at hand as well as a well-planned therapeutic approach.

Volkmann's contracture of the extraocular muscles following blowout fracture.

In the past decade there has been considerable controversy over the surgical indications for treatment of blowout fractures of the orbit. It has been well recognized that some fracture patients develop an ischemic contracture of the inferior rectus muscle. We have found that a Volkmann's type of contracture of the inferior rectus muscle does exist and is similar to that found in the distal extremities. A specific group of fracture patients is at greater risk for development of a contracture. Elderly patients, hypotensive patients, patients with small fractures, and those with high inferior rectus compartment pressures are more prone to developing a contracted extraocular muscle. We have measured compartment pressures in 18 patients who were surgical candidates following orbital fracture. Our conclusions indicate that surgical intervention following blowout fractures in these high-risk patients may be more prudent than medical management. Patients with persistent diplopia due to a contracted inferior rectus are extremely difficult to treat many months after fracture. We still believe it prudent to surgically repair orbital fractures in patients with diplopia, enophthalmos, and a risk for muscle contracture. The documentation of this additional sequela of unrepaired fractures lends more strength to this belief. There is no evidence to indicate that a Volkmann's contracture would be possible after early repair of a blowout fracture.

Practical ptosis surgery. The Wendell L. Hughes Lecture.

The author has emphasized the concept that ptosis surgery should be done in a way that may be modified in the event that the immediate result is not satisfactory. The value of local injection plus fractional anesthesia in the adult allows the surgeon to solicit the aid of the patient to evaluate the result on the table more accurately. A regional block is unsatisfactory because the nerve supply to the levator muscle may be knocked out and titration of the result would not be possible at the time of surgery. The subaponeurotic tunnel without incising the conjunctiva makes a better anatomic dissection of the aponeurosis. The attachment to the tarsus of the advanced aponeurosis 2 to 3 mm from the ciliary border gives the surgeon a leeway of approximately 7 to 8 mm to recess in the event of an overcorrection. In the event of an undercorrection, the aponeurosis is further advanced and reattached by the three vertical mattress sutures.

Margins of safety in lateral orbitotomy.

Five adult cadaver half skulls were used to study the bone cuts of the lateral orbital wall in performing the lateral orbitotomy. Measurements were taken of the anterior vertical opening, the anteroposterior opening, and the distance to the middle cranial fossa. The vertical opening at the anterior aspect of the lateral orbital wall ranged from 18 to 22 mm. The anteroposterior exposure averaged 18 mm when the thick and thin portions of the bone were removed. The distance from the anterior rim to the middle cranial fossa averaged 31 mm on both the superior and inferior cuts. Hence a distance of approximately 12 to 13 mm separated the posterior aspect of the orbitotomy from the middle cranial fossa.