Jose E. Barrera

Measurements of Orbital Volume Change Using Computed Tomography in Isolated Orbital Blowout Fractures

OBJECTIVES To measure the orbital volume of unilateral pure blowout fractures with computed tomography before and after surgery and to compare 3-dimensional (3-D) imaging systems. METHODS Twenty-four patients were evaluated with facial computed tomographic scans before and after surgery. Both the orbital volume and the displaced soft tissue volume were measured by 2 operators using 2 different 3-D software programs (Vitrea; Vital Images Inc, Minnetonka, Minnesota; and Dextroscope; Bracco AMT Inc, Princeton, NJ). RESULTS The mean (SD) normal orbital volumes calculated by Vitrea and Dextroscope were 25.5 (2.4) mL and 24.8 (3.0) mL, respectively. The average preoperative orbital volumes were 28.3 (2.3) mL and 27.6 (3.1) mL, while the postoperative volumes were 25.8 (2.5) mL and 24.9 (3.0) mL. Vitrea showed that the average volume of displaced orbital soft tissue was 2.8 (1.9) mL before surgery and that it was reduced to 0.3 (1.3) mL after surgery, while Dextroscope showed that the average displaced orbital soft tissue was 2.9 (1.4) mL before surgery and that it was reduced to 0.1 (1.2) mL after surgery. There was no statistical difference between the 3-D analysis programs. CONCLUSIONS Consistent volume measurements can be obtained using different 3-D image analysis programs. Measuring preoperative and postoperative volume changes and postoperative reduction can ensure a good surgical result and thereby decrease the incidence of enophthalmos.

Preserving Structural Integrity of the Alar Cartilage in Aesthetic Rhinoplasty Using a Cephalic Turn-in Flap

Resection of the alar cartilage has long been a mainstay of aesthetic rhinoplasty. One drawback of this technique is the destabilization of the ala/lateral nasal wall complex. Herein we describe the cephalic turn-in flap, a technique for reinforcement of the alar cartilage after removal of its cephalic portion.

Sleep magnetic resonance imaging: Dynamic characteristics of the airway during sleep in obstructive sleep apnea syndrome

To determine the dynamic characteristics of airway obstruction in subjects with obstructive sleep apnea (OSA) syndrome.

Comparative computation of orbital volume from axial and coronal CT using three-dimensional image analysis.

Purpose: Volume measurements calculated from axial and coronal CT scans were compared to determine which method more accurately determines orbital volume. Methods: Thirty facial CT scans were used to measure 30 normal orbits using an image analysis program (Dextroscope, Singapore). The 3-dimensional volumes determined from axial scans and coronal scans were analyzed. The coronal scan volume measurements were further subdivided based on anterior limit criteria (termed C1 and C2). Three novel cephalometric angular measurements of the anterior orbital aperture were calculated and used to analyze the volumetric methodologies described above. Results: The calculated orbital volume was greatest on axial scan, 25.6 ± 2.4 ml, followed by volume based on coronal calculations with C1 delimitation (23.8 ± 2.9 ml) and C2 delimitation (16.6 ± 2.2 ml). We measured 3 novel orbital aperture angles on sagittal 3-dimensional reconstruction images, anterovertical, posterovertical, and horizontal orbital aperture angles that are related to the volume measurement underestimation. Conclusion: The orbital volume from coronal scans is underestimated compared with that from the axial scans, and the criterion for anterior limit of measurement can affect volume determination. Three novel cephalometric angle measurements may account for inaccuracies in orbital volume measurements.

High energy single session radiofrequency tongue treatment in obstructive sleep apnea surgery.

Objective To evaluate the safety and outcomes of a high-energy single session treatment as an alternative to a cumulative energy multiple staged approach when using temperature-controlled radiofrequency tissue ablation (TCRFTA) for tongue base obstruction in sleep apnea surgery. STUDY DESIGN AND METHODS Retrospective study of 176 consecutive Fujita II (tongue and palate level obstruction) patients undergoing single session palate, tonsil, and nasal surgery, and concurrent tongue base TCRFTA by the application of 10,500 J of energy. RESULTS Median follow-up was 156.5 days. There were no serious complications. There were five (2.8%) superficial tongue ulcers, and three (1.7%) persistent taste disturbances after treatment; 174 patients were on sustainable oral intake and adequate oral pain control within 24 hours of surgery; 98 had comparable post operative sleep studies. Apnea-hypopnea indexes decreased from 35.3 ± 23.9 to 22.6 ± 21.5 (P < 0.0001). Epworth Sleepiness Scale scores improved from 11.2 ± 4.9 to 5.9 ± 4.6 (P < 0.000001). CONCLUSION High energy single session tongue base TCRFTA is a safe procedure with low morbidity.

Sleep MRI: Novel technique to identify airway obstruction in obstructive sleep apnea

We describe a new tool, “Sleep MRI,” a real-time device that detects and characterizes the anatomic site, magnitude, and duration of airway obstruction simultaneously with MRI-compatible physiologic measures of peripheral arterial tone, hemoglobin oxygen saturation, and pulse rate in patients with obstructive sleep apnea syndrome (OSAS). The goal of the study is to present the safety and feasibility of Sleep MRI. Sleep MRI is a novel technique of airway imaging during sleep that assesses respiratory events measured by ambulatory sleep study technology with simultaneous real-time MR imaging (RT-MRI).

Estrogen and Progesterone Receptor and p53 Gene Expression in Adenoid Cystic Cancer

Objectives The current study examined the role of estrogen receptors (ER), progesterone receptors (PR) and p53 expression in adenoid cystic carcinoma (ACC) to determine if simple expression or possible overexpression of these products might influence the development and natural course of this cancer. Study Design ER and PR status and p53 overexpression were retrospectively evaluated utilizing immunohistochemical evaluation of 47 ACC specimens. Methods Formalin-fixed paraffin-embedded tissues from 47 ACC specimens and 47 samples of normal salivary gland tissue were evaluated histochemically for the presence of ER, PR and p53. Immunoreactivity was scored using a 0 to +3 scale in which staining was either (0) negative, (+1) spotty, (+2) weakly positive, or (+3) strongly positive. Results ER was expressed in 8 of 47 tumors while PR was expressed in 4 of 47 tumors. p53 aberrations were demonstrated in 26 of 47 tumors. Tumors showed varying degrees of immunopositivity ranging from 0 to +3. Conclusions These studies suggest that p53 aberrations may be involved in ACC tumor progression and that ER and PR may play a role in ACC development.

Reliability of airway obstruction analyses from Sleep MRI sequences

Objective: A real-time MRI “movie” during natural sleep (“Sleep MRI”) allows observation of dynamic airway obstructions in obstructive sleep apnea syndrome (OSAS) patients. The purpose of this article was to determine the reliability of assessing these obstructions. Study Design: Cross-sectional diagnostic test evaluation. Setting: Academic referral center. Subjects and Methods: A total of 23 Sleep MRI sequences randomly selected from 20 consecutive OSAS patients were analyzed by two experienced sleep surgeons on two separate occasions separated by at least two weeks. Five dimensions were assessed: presence or absence of any obstruction, presence or absence of a retropalatal obstruction, presence or absence of a retroglossal obstruction, presence or absence of a swallow, and duration of an obstructive event. Results: For all dimensions measured, intra-rater reliability coefficients ranged from a low of 0.95 to a high of 1.0 for each rater. Inter-rater reliability coefficients ranged from a low of 0.85 to a high of 1.0. On two separate evaluations separated by at least two weeks, rater 1 identified a retropalatal obstruction in 100 percent of sequences, whereas rater 2 did so in 91 percent and 96 percent of the sequences, respectively. Retroglossal obstruction was identified in 57 percent (rater 1) and 65 percent (rater 2) of sequences. Conclusion: Intra-rater and inter-rater reliability coefficients are very high for determination of presence or absence of any obstruction, presence or absence of a retropalatal obstruction, presence or absence of a retroglossal obstruction, presence or absence of a swallow, and duration of obstruction from Sleep MRI sequences in OSAS patients.

Three-Dimensional Analysis of Zygomatic-Maxillary Complex Fracture Patterns

Zygomatic-maxillary (ZMC) complex fractures are a common consequence of facial trauma. In this retrospective study, we present a novel method of ZMC fracture pattern analysis, utilizing three-dimensional visualization of computed tomography (CT) images to record displacement of the malar eminence in a three-dimensional coordinate plane. The pattern of fracture was then correlated with treatment outcome. Facial CT scans were obtained from 29 patients with unilateral ZMC fractures and 30 subjects without fractures and analyzed. Briefly, displacement of the malar eminence (ME) on the fractured side was measured in medial-lateral (x), superior-inferior (y), and anterior-posterior (z) dimensions, as well as Euclidean distance, by comparison to ME location on the unfractured side. Baseline natural variance in asymmetry was accounted for by comparing ME location on the left and right sides in subjects without fractures. Patients who required open reduction and internal fixation (ORIF) to repair the ZMC fracture alone had significantly greater cumulative ME displacements than patients who did not require ORIF (p = 0.02). Additionally, patients with a high fracture score of 3, 4, or 5 (assigned based on severity displacement in each dimension) had significantly higher rates of ORIF than patients with a low fracture score of 0, 1, or 2 (p = 0.05). Severe displacement in one or more dimensions was associated with higher rates of ORIF than seen in patients with only neutral or mild displacements in all dimensions (p = 0.05). Severe x displacement was most strongly correlated with surgical intervention (p = 0.02). Overall, orbital floor repair was less strongly associated with most displacement measures than ZMC repair alone; however, patients requiring orbital floor repair had greater Euclidean ME displacements than patients who did not require orbital floor repair (p = 0.02). Fracture severity, as determined by multiple parameters in this novel evaluation system, is associated with higher rates of ORIF in patients with unilateral ZMC fractures. Determination of ZMC fracture pattern may thus be informative when considering treatment options.

An Analysis of Malar Fat Volume in Two Age Groups: Implications for Craniofacial Surgery

Objective To evaluate how malar fat pad (MFP) volumes vary with age, after controlling for gender and body mass index (BMI). Study Design A prospective case–control study evaluating volume of the MFP in women of two age groups. Methods Soft tissue dimensions were measured in eight subjects using magnetic resonance imaging. A multiplanar localizing sequence, followed in sagittal and coronal orientations using a turbo spin echo sequence, was performed to define the MFP. Volumetric calculations were then performed using a 3D image analysis application (Dextroscope, Volume Interactions, Republic of Singapore) to circumscribe areas, orient dimensions, and calculate volumes of the MFP. Results These data reveal no significant difference in the mean (standard deviation) right MFP (p = 0.50), left MFP (p = 0.41), or total MFP (p = 0.45) volumes when comparing the two age groups. In addition, these data indicate that there was no correlation between age and total MFP volume (Pearson correlation coefficient 0.27). Moreover, there was no correlation between age and the ratio of total volume/BMI (Pearson correlation coefficient −0.18). Conclusions Although the sample size of this study was small, these data indicate that ptosis of midfacial fat is more important than volume loss in midfacial aging. These data would suggest repositioning as the primary modality for craniofacial reconstruction.