Signal-To-Noise Ratio Calculations to Validate Sensor Positioning for Facial Muscle Assessment Using Noninvasive Facial Electromyography.

The evaluation of neuromodulator treatment outcomes can be performed by noninvasive surface-derived facial electromyography (fEMG) which can detect cumulative muscle fiber activity deep to the skin. The objective of the present study is to identify the most reliable facial locations where the motor unit action potentials (MUAPs) of various facial muscles can be quantified during fEMG measurements. The study population consisted of five males and seven females (31.0 [12.9] years, body mass index of 22.15 [1.6] kg/m2). Facial muscle activity was assessed in several facial regions in each patient for their respective muscle activity utilizing noninvasive surface-derived fEMG. Variables of interest were the average root mean square of three performed muscle contractions (= signal) (µV), mean root mean square between those contraction with the face in a relaxed facial expression (= baseline noise) (µV), and the signal to noise ratio (SNR). A total of 1,709 processed fEMG signals revealed one specific reliable location in each investigated region based on each muscle's anatomy, on the highest value of the SNR, on the lowest value for the baseline noise, and on the practicability to position the sensor while performing a facial expression. The results of this exploratory study may help guiding future researchers and practitioners in designing study protocols and measuring individual facial MUAP when utilizing fEMG. The locations presented herein were selected based on the measured parameters (SNR, signal, baseline noise) and on the practicability and reproducibility of sensor placement.

Frontal sinus fractures: a treatment algorithm and assessment of outcomes based on 78 clinical cases.

BACKGROUND: The purposes of this article were to retrospectively review frontal sinus fractures at the authors' center, to assess the final outcomes, and to establish a treatment algorithm. METHODS: A retrospective chart review was performed on 78 consecutive frontal sinus fractures treated by the same surgeon between January 1, 1994, and January 1, 2002. RESULTS: In this study, 57.7 percent of fractures occurred as a result of motorcycle accidents and 75.6 percent of those patients were not wearing helmets at the time of injury. The use of helmets did not significantly affect the fracture pattern. Frontal sinus fractures were commonly associated with orbital fractures (71 percent), intracranial injuries (39 percent), and severe ophthalmic injuries (26 percent). Associated injuries were more common when the fractures involved the posterior tables. The method of management comprised four groups: no surgical intervention (n = 6), open reduction and internal fixation of the anterior table with sinus preservation (n = 40), partial sinus obliteration (n = 18), and cranialization (n = 14). The complication rate was 16.7 percent (n = 13), including postoperative cerebrospinal fluid leaks (n = 6), wound infections (n = 4), meningitis (n = 1), sinusitis (n = 1), and pyomucocele (n = 1). CONCLUSIONS: Involvement of the nasofrontal duct and persistence of cerebrospinal fluid leaks are two key determinants of the treatment algorithm. The amount of displacement of the posterior table has not been found to be a key determinant of the need for surgical intervention. When the sinus is to be obliterated, partial obliteration can achieve a good result, with limited sinus complication and minimal donor-site morbidity.

Resource cost comparison of implant-based breast reconstruction versus TRAM flap breast reconstruction.

Relatively little has been published to date comparing the resource costs of transverse rectus abdominis musculocutaneous (TRAM) flap and prosthetic breast reconstruction. The data that have been published reflect the experience at just one medical center with a previously known clear preference for autologous breast reconstruction. The goal of this study was to compare the resource costs of TRAM flap and prosthetic reconstruction in an institution where both procedures continue to be performed using modern techniques and at a relatively equivalent frequency. All available medical records were reviewed for patients who had completed their breast reconstruction between 1987 and 1997. Records of patients who had undergone TRAM flap or prosthetic reconstruction were reviewed to compare resource costs, including hospital stay, operating room time, anesthesia time, prosthetic devices, and physician's fees. Of 835 patients reviewed who had completed breast reconstruction, a total of 140 suitable patients were identified who had all the necessary financial information available. The patient population comprised 64 patients who received TRAM flaps and 76 patients who had undergone prosthetic reconstruction. The length of stay for the TRAM flap group, including all subsequent admissions for each patient, ranged from 2 to 24 days (mean, 6.25 days), and that for the prosthetic reconstruction group ranged from 0 to 20 days (mean, 4.36 days). Operating room time for the complete multistage reconstructive process for a TRAM flap ranged from 5 hours, 20 minutes to 12 hours, 25 minutes (mean, 7 hours, 34 minutes); with implant-based reconstruction, operating time ranged from 1 hour, 45 minutes to 8 hours, 56 minutes (mean, 4 hours, 6 minutes). With prostheses costing from $600 to $1200, a surgeon's fee of $160/hour, and an assistant's fee of $45/hour, the average cost of TRAM flap reconstructions was $19,607 (range, $11,948 to $49,402), compared with $15,497 for prosthetic reconstructions (range, $6422 to $40,015). The results were statistically significant (p < 0.001). Several factors weigh into the decision as to which reconstructive operation best suits the patient's needs. These factors include surgical risk, potential morbidity, and aesthetic results. On the basis of this review of autologous and prosthetic breast reconstruction in an institution where both are performed frequently, during a 10-year period with a mean time elapsed since reconstruction of 7.45 years, prosthetic reconstruction was significantly less expensive.

Assessment of bilateral cleft lip nose deformity: a comparison of results as judged by cleft surgeons and laypersons.

Reconstruction of bilateral cleft lip nose deformity is difficult and the outcome is inconsistent. This study was conducted to evaluate the gross outcome and the difference in the assessment of nasal appearance as judged by two groups of raters, cleft surgeons and laypersons. Sixty-four patients with bilateral cleft lip were selected for review. The patients' ages ranged from 5 to 30 years. All patients had undergone primary cleft lip repair and secondary nasal reconstruction, and had been followed for at least 6 months. One image for each patient, which included a digitized frontal, lateral, and worm's-eye view, was projected for evaluation by the raters. The raters included five cleft surgeons and five laypersons. A rating scheme was used in which a score of 3 was given for a good, close to normal nasal appearance, 2 for an average result that needed minor revision, and 1 for a poor result that needed major reconstruction. The scores were averaged for each patient in each group and for each group as a whole. The final outcome was judged as good, fair, or poor on the basis of the mean score for each patient. Statistical analysis was performed. The mean score for all patients was 2.08 as assessed by the laypersons and 2.18 as assessed by the cleft surgeon group. There was no statistically significant difference between the two groups. Comparisons on rating scores among different raters revealed a fair agreement on the ratings within each of the two groups. The results were found to be good in 29.7 percent, fair in 64.1 percent, and poor in 6.3 percent of patients when evaluated by the surgeons. When rated by the laypersons, the nasal appearance was found to be good in 26.6 percent, fair in 60.9 percent, and poor in 12.5 percent of patients. This difference in distribution between the two groups was not statistically significant. When comparing the results given by the two groups of assessors, there was agreement on the nasal appearance in 65.6 percent of patients, and a difference in grading in the rest. For the patients who received different grading, the surgeons rated them one grade higher in 63.6 percent and one grade lower in 36.4 percent. There was no difference in grading between any of the evaluators that reflected a two-grade discrepancy in evaluation of results. This study shows that the surgical outcome of bilateral cleft lip nose deformity repair, at the authors' institution, is less than optimal. When assessing bilateral cleft lip nose appearance, the judgment of results by cleft surgeons was similar to that of the laypersons. However, different rating of results existed within each of the two groups, supporting the importance of clearly assessing patient/parent expectations and defining realistic surgical goals.