Biomedical subjects

Stephen E Metzinger

Publications and source records attributed to Stephen E Metzinger.

6 recordsLinked to original sources

PubMed2005

Frontal sinus fractures: management guidelines.

Management of frontal sinus fractures (FSF) has been the subject of great debate for more than six decades. Multiple treatment options and algorithms have been proposed by multiple specialties throughout the years; however, the optimal method of frontal sinus repair has yet to be elucidated. Because of the location of the frontal sinus and its proximity to numerous intracranial structures, inadequate treatment may lead to life-threatening intracranial infectious complications. Meningitis, encephalitis, and brain abscess are the most common intracranial complications. Other complications include persistent cerebrospinal leakage, mucopyoceles, frontal osteomyelitis, meningoencephalocele, and nonunion of the frontal bone. Orbital involvement may result in ophthalmoplegia, orbital abscess, diplopia, enophthalmos, proptosis, preseptal cellulitis, and partial or complete loss of vision. Morbidity and mortality are often dependent on the anatomic characteristics of the fracture, concomitant injuries, treatments rendered, age, gender, and mechanism of injury. Management of frontal sinus fractures is so controversial that the indications, timing, method of repair, and surveillance remain disputable among several surgical specialties. The most important tenet of frontal sinus fracture management remains the same: create a safe sinus. This is accomplished by following four basic principles: reestablish the frontal bony contour to its premorbid state, restore normal sinus mucosa with a patent drainage system if possible, eradicate the sinus cavity if the normal mucosa or drainage system cannot be reestablished, and create a permanent barrier between the intracranial and extracranial systems to prevent overwhelming infectious complications. By following these four basic principles, frontal sinus fracture management will be safe and effective as long as extended surveillance is part of the protocol.

Adult↗

PubMed2004

A 10-year retrospective review of 758 DIEP flaps for breast reconstruction.

This study examined 758 deep inferior epigastric perforator flaps for breast reconstruction, with respect to risk factors and associated complications. Risk factors that demonstrated significant association with any breast or abdominal complication included smoking (p = 0.0000), postreconstruction radiotherapy (p = 0.0000), and hypertension (p = 0.0370). Ninety-eight flaps (12.9 percent) developed fat necrosis. Associated risk factors were smoking (p = 0.0226) and postreconstruction radiotherapy (p = 0.0000). Interestingly, as the number of perforators increased, so did the incidence of fat necrosis. There were only 19 cases (2.5 percent) of partial flap loss and four cases (0.5 percent) of total flap loss. Patients with 45 flaps (5.9 percent) were returned to the operating room before the second-stage procedure. Patients with 29 flaps (3.8 percent) were returned to the operating room because of venous congestion. Venous congestion and any complication were observed to be statistically unrelated to the number of venous anastomoses. Overall, postoperative abdominal hernia or bulge occurred after only five reconstructions (0.7 percent). Complication rates in this large series were comparable to those in retrospective reviews of pedicle and free transverse rectus abdominis musculocutaneous flaps. Previous studies of the free transverse rectus abdominis musculocutaneous flap described breast complication rates ranging from 8 to 13 percent and abdominal complication rates ranging from 0 to 82 percent. It was noted that, with experience in microsurgical techniques and perforator selection, the deep inferior epigastric perforator flap offers distinct advantages to patients, in terms of decreased donor-site morbidity and shorter recovery periods. Mastery of this flap provides reconstructive surgeons with more extensive options for the treatment of postmastectomy patients.

Adolescent↗

PubMed2004

The role of topically administered FK506 (tacrolimus) at the time of facial nerve repair using entubulation neurorrhaphy in a rabbit model.

Peripheral facial nerve palsy is a common sequela of traumatic craniofacial injury, often resulting in dramatic and sometimes permanent functional deficits. Exogenous agents and methods of repair that accelerate axonal regeneration would be of great benefit to the multitude of patients with facial nerve injuries. The objective of this study was to evaluate the effect of FK506 at the time of facial nerve repair using entubulation neurorrhaphy, and to compare entubulation neurorrhaphy versus interposition autograft in critical facial nerve gap defects. The study design was a prospective, randomized, blinded animal study with a control group. Twenty-five New Zealand White rabbits were assigned to 4 experimental groups and a control group. The buccal branch of the facial nerve was used in all procedures. Group 1 was the control group. Rabbits in group 2 underwent sham surgery. Group 3 was an interposition autograft group in which a 6-mm segment of nerve was transacted, flipped, and followed by epineural repair. Groups 4 and 5 underwent transection followed by entubulation neurorrhaphy with topical administration of either a carrier molecule (group 4) or an FK506 carrier molecule (group 5). Outcome measures included daily subjective assessment of upper lip movement; electromyographic studies at weeks 3, 5, and 8 postoperatively; and blinded quantitative histomorphometric evaluation after 8 weeks. All rabbits in all groups were noted to have spontaneous movement after 8 weeks, with 1 rabbit in group 5 obtaining the highest functional score among all study groups. Electrophysiologic studies showed polyphasic potentials, indicating reinnervation in 1 rabbit in group 5. Histomorphometric examination of group 5 rabbits revealed a similar cross-sectional area distal to transection and remyelination. Other groups showed decreased cross-sectional area and/or incomplete remyelination distal to the transection. FK506 applied topically at the time of facial nerve repair using entubulation neurorrhaphy demonstrated superior results in nerve regeneration versus entubulation neurorrhaphy carrier protein alone, and interposition autograft.

Administration, Topical↗

PubMed2003

Clinical implications of the innervation of the temporomandibular joint.

The successful management of temporomandibular joint (TMJ) pain remains elusive. Often, the initial relief of pain is complicated by recurrence of the symptoms. This time frame suggests that the pain may be related to neuromas of the nerves that innervate the TMJ. The current study attempted to define the innervation pattern of the TMJ as identified in 16 embalmed and 8 fresh-frozen specimens. In each specimen, the auriculotemporal nerve, a branch of the mandibular portion (V3) of the trigeminal nerve, was found to innervate the lateral capsule of the TMJ. In 75% of the specimens, the masseteric nerve, a branch of the maxillary portion (V2) of the trigeminal nerve, was found to innervate the anteromedial capsule of the TMJ. In 33% of the specimens, there was a branch coming through the mandibular notch to innervate the anteromedial capsule that was not from the masseteric nerve; this nerve is believed to have passed through the lateral pterygoid muscle after leaving V2. These consistent patterns of innervation of the TMJ suggest that diagnostic nerve blocks can be done to determine the pain pathway in these patients. It is suggested that if the nerve blocks are successful, TMJ denervation may be a future method of pain relief in patients with recalcitrant or recurrent TMJ pain.

Cadaver↗

PubMed2002

Transconjunctival upper blepharoplasty: a safe and effective addition to facial rejuvenation techniques.

Transconjunctival techniques for eyelid rejuvenation are now well accepted in the lower eyelid. Transconjunctival upper blepharoplasty is a relatively new technique for which overall experience has been limited. Since October 1998, the authors performed 42 bilateral transconjunctival upper blepharoplasties on patients undergoing facial and eyelid rejuvenation. They describe the essential anatomy and technique of the procedure. The CO2 laser is used concomitantly for treating fine rhytids and tightening loose upper eyelid skin. This procedure is an effective method of removing medial upper eyelid fat with minimal complications.

Blepharoplasty↗

PubMedDate not supplied

Quantifying the arch position of the female eyebrow.

OBJECTIVE: To devise a quantitative aesthetic model for the eyebrow arch position (EAP) in women. METHODS: Full-face frontal magazine photographs of 100 fashion models published between January and July 2001 were analyzed. Apparent EAP relative to a line through the medial canthus parallel to the midline was compared with eyewidth (EW). A similar comparison was made between the lateral limbus (LL) and the EW. Standardized full-face frontal photographs of 105 randomly selected women aged 21 to 61 years were taken after obtaining informed consent. The photographs were analyzed in the same manner as those of the fashion models. Both populations had the medial and lateral extents of their eyebrows analyzed. RESULTS: The mean +/- SD EAP:EW ratio for the fashion models was 0.978 +/- 0.131; the mean +/- SD LL:EW ratio was 0.735 +/- 0.0673. The mean +/- SD EAP:EW ratio for the randomly selected group was 0.929 +/- 0.146; the mean +/- SD LL:EW ratio was 0.762 +/- 0.0420. CONCLUSIONS: The EAP has been described as being above the LL. This does not reflect the EAP seen in both of our study groups. The EAP seems to be 93% to 98% of an EW in the aesthetic model derived from these data.

Adult↗