Surgical anatomy of the face: implications for modern face-lift techniques.

OBJECTIVE: To delineate the anatomic architecture of the melolabial fold with surrounding structures and to elucidate potential implications for face-lift techniques. METHODS: A total of 100 facial halves (from 50 cadaveric heads) were studied, including gross and microscopic dissection and histologic findings. Laboratory findings were correlated with intraoperative findings in more than 150 deep-plane face-lift dissections (300 facial halves) performed during the study period. RESULTS: In contrast to previous reports, the superficial musculoaponeurotic system (SMAS) was not found to form an investing layer in the midface. The SMAS, zygomatici muscles, and levator labii superioris alaeque nasi were found to be located in corresponding anatomic layers and to form a functional unit. Additional findings of the present study include the description of 3 structurally different portions of the melolabial fold, of an anatomic space below the levator labii superioris alaeque nasi (sublevator space), and of extensions of the buccal fat pad into the sublevator space and the middle third of the melolabial fold. CONCLUSIONS: The findings of the present study may contribute to augment our understanding of the complex anatomy of the midface and melolabial fold. Potential implications for modern face-lift techniques are discussed.

Comparison of 4 registration strategies for computer-aided maxillofacial surgery.

PURPOSE: Surgeons have recently started to use computer-aided surgery (CAS) to assist with maxillofacial reconstructive surgery. This study evaluates four different CAS registration strategies in the maxillofacial skeleton. MATERIALS AND METHODS: Fifteen fiducial markers were placed on each of four cadaveric heads. Four registration protocols were used: 1) group 1-invasive markers, 2) group 2-skin surface, 3) group 3-bony landmark, 4) group 4-intraoral splint. Two observers registered each head twice with each of the four protocols and measured the target registration error (TRE). The process was repeated on two different navigation systems for confirmation. RESULTS: The mean TRE values were: invasive, 1.13 +/- 0.05 mm (P < 0.05); skin, 2.03 +/- 0.07 mm (P < 0.05); bone, 3.17 +/- 0.10 mm (P < 0.05); and splint, 3.79 +/- 0.13 mm (P < 0.05). The TRE values were consistent across CAS systems. CONCLUSION: Of the techniques tested for CAS registration, invasive fiducial markers are the most accurate. Skin surface landmarks, bony landmarks, and an intraoral splint are incrementally less accurate.

Computer modeling and intraoperative navigation in maxillofacial surgery.

PURPOSE: Recent advances in computer-modeling software allow reconstruction of facial symmetry in a virtual environment. This study evaluates the use of preoperative computer modeling and intraoperative navigation to guide reconstruction of the maxillofacial skeleton. METHODS: Three patients with traumatic maxillofacial deformities received preoperative, thin-cut axial CT scans. Three-dimensional reconstructions, virtual osteotomies, and bony reductions were performed using MIMICS planning software (Materialise, Ann Arbor, MI). The original and "repaired" virtual datasets were then imported into an intraoperative navigation system and used to guide the surgical repair. RESULTS: Postoperative CT scans and photographs reveal excellent correction of enophthalmos to within 1 mm in patient 1, significant improvement in symmetry of the nasoethmoid complex in patient 2, and reconstruction of the zygomaticomaxillary complex location to within 1 mm in patient 3. CONCLUSION: Computer modeling and intraoperative navigation is a relatively new tool that can assist surgeons with reconstruction of the maxillofacial skeleton.

Intraoral transposition of traumatic parotid duct fistula.

Parotid duct fistula is uncommon but difficult-to-treat complication that often results from a penetrating trauma. While there is general consensus in the literature as to the management of acute parotid injuries, treatment of chronic fistulas remains controversial. We review the current treatment options for parotid duct fistulas and describe an intraoral diversion technique to reestablish salivary flow in the setting of a nonfunctional parotid duct punctum.

Comparison between Two Scheimpflug Anterior Segment Analyzers.

PURPOSE: To compare the anterior segment indices measured by two Scheimpflug camera machines; Galilei and Pentacam. METHODS: In this observational case series, the anterior segment indices of myopic healthy subjects seeking for refractive surgery were measured by Pentacam and Galilei on the same day. Analyzed parameters were anterior and posterior best fit spheres (BFS), axial curvature, true corneal power, central corneal thickness (CCT), anterior chamber (AC) depth, AC volume, AC angle, and pupil diameter. RESULTS: This study included 176 eyes of 88 participants. Mean radius of the anterior BFS was 7.79 ± 0.34 mm versus 7.75 ± 0.39 mm measured by Pentacam and Galilei, respectively (r = 0.877, P < 0.001). Corresponding values for the mean radius of posterior BFS were 6.42 ± 0.32 and 6.47 ± 0.38 mm, respectively (r = 0.879, P < 0.001). Anterior corneal mean power was 43.8 ± 1.9 diopters (D) with Pentacam and 43.8 ± 2.4 D with Galilei (r = 0.905,P < 0.001). Posterior corneal mean power was measured - 6.3 ± 0.3 and - 6.3 ± 0.4 D using Pentacam and Galilei, respectively (r = 0.873, P < 0.001). True corneal power was 43.9 ± 1.9 D with Pentacam and 43.5 ± 2.3 D with Galilei (r = 0.909, P < 0.001). CCT was 537 ± 44 and 553 ± 51 µm measured by Pentacam and Galilei, respectively (r = 0.796, P < 0.001). AC depth measurements using Pentacam and Galilei were 3.29 ± 0.4 and 3.3 ± 0.38 mm (P < 0.001), respectively; AC volume was 207 ± 50 and 129 ± 39 mm3≥ (P = 0.004), and AC angle was 39.7 ± 9.2 and 54.2 ± 5.2 degrees (P = 0.051), respectively. Average pupil diameter was measured 3.91 ± 1.77 mm by Pentacam and 3.34 ± 0.89 mm by Galilei (P = 0.018). CONCLUSIONS: There was a significant correlation between the Pentacam and Galilei in all measured parameters except AC angle, AC volume, and average pupil diameter.

Anatomical 3-dimensional pre-bent titanium implant for orbital floor fractures.

PURPOSE: This cadaver study evaluates the use of pre-bent 3-dimensional titanium mesh implants for orbital floor and medial wall reconstruction. DESIGN: Nonrandomized comparative study. PARTICIPANTS: Eight human cadaveric heads (n = 16 orbits). METHODS: Transcutaneous incisions were used to expose both orbital floors in each cadaveric head. Unilateral orbital floor and medial wall fractures were generated in each specimen. The contralateral orbit remained uninjured. The fractures then were repaired with pre-bent titanium mesh fan plates molded from aluminum templates presenting different sizes. The templates were generated from topographical computed tomography (CT) data previously obtained from normal subjects. The accuracy of orbital reconstruction was evaluated with postoperative CT scans. MAIN OUTCOME MEASURES: The mean value of the distances between the implant and the bony orbit was evaluated. RESULTS: The mean distance between all 16 plates and their respective orbital floors/medial walls was 0.81+/-0.74 mm. Mean values were 0.68+/-0.63 mm for the unfractured side and 0.93+/-0.82 mm for the fractured side. No significant differences were found between orbits when evaluated for side of injury, gender, or size of defect. CONCLUSION: Pre-bent 3-dimensional titanium mesh implants provide accurate reconstruction of orbital floor and medial orbital wall fractures. The mean implant error was <1 mm for all orbits studied.

Upper and lower eyelid reconstruction: the year in review.

PURPOSE OF REVIEW: Depending on the size, location, and extent of defects, a myriad of surgical approaches may be utilized to repair the eyelids. An understanding of the principles of lid reconstruction as well as orbital and periorbital anatomy is essential when approaching the repair of eyelid defects. While principles of eyelid reconstruction have been established, achieving good functional and aesthetic reconstruction remains challenging. This review examines the methodology of reconstructing eyelid defects, as reported over the last year. RECENT FINDINGS: Eyelid reconstruction continues to encompass a wide range of reconstructive options. Reports range from simple modifications of traditional techniques to the use of complex flaps and grafts. SUMMARY: While set algorithms have been proposed regarding eyelid reconstruction, the method of choice will ultimately depend on a combination of factors, including availability of tissues, and a surgeon's experience with the available modes of reconstruction.

Advances in scalp reconstruction.

PURPOSE OF REVIEW: The present review summarizes traditional and advanced techniques used to reconstruct defects of the scalp. These deformities range from small defects that can be closed primarily to significant defects, which require free tissue transfer. RECENT FINDINGS: Increased use of tissue expanders, advancement rotational flaps, and hair transplantation has resulted in improved cosmetic outcomes for larger defects of the scalp. Free tissue transfer has provided a revolutionary method of reconstructing subtotal and total defects of the scalp, in particular those associated with neoplasms. SUMMARY: New advances in techniques of scalp reconstruction have provided improved outcomes in terms of cosmetic appearance and decreased morbidity for scalp reconstruction.

Psychophysical observations on patients with neuropathic pain relieved by a sympathetic block.

Patients with sympathetically maintained pain (SMP) were tested with noxious heat pulses, innocuous mechanical stimuli, and transcutaneous electrical nerve stimulation before and during local anesthetic sympathetic blocks that relieved their pain. The perceived intensity of the pain evoked by these stimuli was measured by the patients' responses on a visual analog scale and compared to the responses obtained when the same stimuli were applied to contralateral normal skin. In 5 of 7 patients tested, graded noxious heat stimuli (43-51 degrees C) applied to painful skin resulted in heat-pain intensity ratings that were essentially identical to the responses obtained when the same stimuli were applied to the normal side. Of the remaining two patients, one was clearly hypoalgesic for heat-pain and the other was probably hyperalgesic. The normal and subnormal heat-evoked responses obtained from abnormal skin were unchanged during completely successful sympathetic blocks. Trains of noxious heat pulses (52 degrees C) evoked summation of the second pain sensation in each of the 4 patients tested. This summation effect was normal and unaffected by a sympathetic block. Four of the patients had allodynia evoked by mechanical stimulation. In each of the 3 allodynia cases tested, transcutaneous nerve stimulation at an intensity that was at threshold for detection evoked burning pain and a coexistent sensation of tingle, indicating that both sensations were due to the activation of A beta axons. Patients without touch-evoked pain reported that electrical stimuli at threshold for detection produced only the sensation of tingle. The pains evoked by touch and by threshold-strength nerve stimulation were eliminated during sympathetic block. In patients with allodynia, trains of gentle mechanical stimuli and trains of threshold-strength electrical nerve stimuli produced summation of the intensity of the burning pain sensation when the stimuli were presented at 0.3 Hz. These results add to a growing body of evidence indicating that the touch-evoked pain of some patients is due to abnormal central activity evoked by input from A beta low-threshold mechanoreceptors. The coexistence of A beta-evoked pain with normal heat-evoked pain and normal heat-pain summation suggests that the central abnormality cannot be a simple hypersensitivity of wide-dynamic-range neurons. The effect of sympathetic blockade on A beta-evoked pain and its summation suggests that the crucial sympathetic interaction may take place centrally. The results show that there is considerable heterogeneity of sensory abnormalities among patients with SMP.(ABSTRACT TRUNCATED AT 400 WORDS)

The validation of visual analogue scales as ratio scale measures for chronic and experimental pain.

Visual analogue scales (VAS) of sensory intensity and affective magnitude were validated as ratio scale measures for both chronic and experimental pain. Chronic pain patients and healthy volunteers made VAS sensory and affective responses to 6 noxious thermal stimuli (43, 45, 47, 48, 49 and 51 degrees C) applied for 5 sec to the forearm by a contact thermode. Sensory VAS and affective VAS responses to these temperatures yielded power functions with exponents 2.1 and 3.8, respectively; these functions were similar for pain patients and for volunteers. The power functions were predictive of estimated ratios of sensation or affect produced by pairs of standard temperatures (e.g. 47 and 49 degrees C), thereby providing direct evidence for ratio scaling properties of VAS. Vas sensory intensity responses to experimental pain, VAS sensory intensity responses to different levels of chronic pain, and direct temperature (experimental pain) matches to 3 levels of chronic pain were all internally consistent, thereby demonstrating the valid use of VAS for the measurement of and comparison between chronic pain and experimental heat pain.

A simultaneous comparison of fentanyl's analgesic effects on experimental and clinical pain.

Intravenous administration of 0.8 microgram/kg and 1.1 micrograms/kg fentanyl in low back pain patients reduced both sensory intensity and unpleasantness visual analogue scale (VAS) responses to experimental pain evoked by graded 5-sec nociceptive temperature stimuli (45-51 degrees C) as well as VAS-sensory and VAS-affective responses to clinical pain. Fentanyl produced similar decreases in VAS-sensory responses to experimental and clinical pain. Fentanyl produced nearly equal reductions in VAS-sensory and VAS-affective responses to experimental pain but greater reductions in clinical pain VAS-affective as compared to clinical pain VAS-sensory responses. This interaction of type of pain (experimental versus clinical) and pain dimension (sensory versus affective) results from either a steeper sensory intensity-unpleasantness relationship for clinical pain as compared to experimental pain or additional selective influences of opiates on affective factors uniquely related to clinical pain. These results indicate that low to moderate doses of opiates reduce both sensory and affective dimensions of pain and strongly suggest that changes in pain affect occur mainly as a direct consequence of reductions in pain sensation intensity.

A canonical correlation analysis of the influence of neuroticism and extraversion on chronic pain, suffering, and pain behavior.

The relationship between neuroticism and extraversion on the 4 major stages of pain processing, that of pain sensation intensity, pain unpleasantness, suffering, and pain behavior, were studied in 205 chronic pain patients (88 male and 117 female). Patients underwent psychological evaluation which included the Pain Experience visual analogue scales (VAS) (Price et al. 1983), NEO Personality Inventory (NEO-PI) (Costa and McCrae 1985), and the Psychosocial Pain Inventory (PPI) (Getto and Heaton 1980). Canonical correlation was used to control for pain sensation intensity in evaluating affective dimensions of pain and to control for neuroticism in assessing effects of extraversion on different stages and dimensions of pain. Neither neuroticism nor extraversion were related to pain sensation intensity. Only neuroticism was associated with pain unpleasantness. Personality factors had their greatest impact on stages 3 (suffering) and 4 (illness behavior) of pain processing. The results of multiple regression analyses indicated that life-long vulnerability to anxiety and depression is paramount in understanding the relationship between personality and suffering in chronic pain. These findings provide support for the idea that personality traits influence the ways in which people cognitively process the meanings that chronic pain holds for their life, and hence the extent to which they suffer.

Clinical and genetic characterization of frontorhiny: report of 3 novel cases and discussion of the surgical management.

OBJECTIVES: To (1) define the nasal, columellar, and lip deformities of 3 patients with characteristics consistent with frontorhiny; (2) illustrate the embryologic correlation of the oronasal findings to the development of the median nasal prominence; (3) report the clinical manifestation in 3 patients from 2 unrelated families; (4) report a novel Y214X mutation in ALX3 ; and (5) describe the surgical reconstruction. METHODS: In this case series, we report 3 novel cases of frontorhiny from 2 different families. The surgical reconstruction technique is reviewed. Extension of the columellar medial crural cartilage into the upper lip cleft is examined histologically. Signed consent was granted for all patient photographs and specimens, and the study was approved by the institutional review committee of the University of California Davis The genetic sequencing of the ALX3 homeobox gene was performed in 2 of our 3 cases using standard commercially available sequencing kits. The genetic material in our third case was not available for analysis. RESULTS: Patients 1 and 2 were brothers from the same family. Both exhibited bifidity of their columella, a widened philtrum, poor nasal tip development, and low hairlines. Genetic sequencing in the 2 brothers confirmed the presence of a novel ALX3 homeobox mutation at the second exon (mutation Y214X). Patient 3 was a 4-year-old girl. She presented with an underdeveloped, widened nasal tip and a bifid columella. Her philtrum was widened and had a left-sided cartilaginous prominence. She also had a widened nasal root. Family history revealed no family members with the same features. CONCLUSIONS: Frontorhiny represents a new syndromic frontonasal malformation with consistent characteristic features. The genetic abnormality has now been found in 14 different patients. Careful scrutiny and classification of frontonasal deformities will expand our understanding of causes, genetic susceptibility, and treatment options.

Comparison of 3 optical navigation systems for computer-aided maxillofacial surgery.

OBJECTIVE: To compare the accuracy of 3 computer-aided surgery systems for maxillofacial reconstruction. DESIGN: Evaluation of 3 computer-aided surgery systems: StealthStation, VectorVision, and Voxim. SETTING: The University of California, Davis, Department of Otolaryngology computer-aided surgery laboratory. PARTICIPANTS: Four fresh cadaveric heads. MAIN OUTCOME MEASURE: Mean target registration error. RESULTS: The StealthStation was the most accurate (mean [SD] target registration error, 1.00 [0.04] mm), followed by VectorVision (1.13 [0.05] mm) and then Voxim (1.34 [0.04] mm). All values met statistical significance (P < .05). CONCLUSIONS: Measurable accuracy differences were found among the navigation systems evaluated. The StealthStation was the most accurate. However, the differences are small, and the clinical significance for maxillofacial reconstruction is negligible.