Venous duplex and pathologic differences in thrombus characteristics between de novo deep vein thrombi and endovenous heat-induced thrombi.

OBJECTIVE: Superficial venous reflux disease has been treated with endovenous ablation techniques for more than 15 years. Thrombi discovered in the postoperative period are referred to as endovenous heat-induced thrombi (EHIT). In spite of the few studies of the ultrasound differentiation between EHIT and deep vein thrombi (DVT), there remains a paucity of literature regarding the evaluation of ultrasound examination and pathologic differentiation. METHODS: Six Yorkshire cross swine underwent femoral vein thrombosis by suture ligation or endovenous radiofrequency ablation. At 1 week after the procedure, each femoral vein was imaged by color Duplex ultrasound and sent for histologic interpretation for differentiation between EHIT and DVT. Five blinded vascular surgery faculty, two vascular surgery fellows, and three vascular surgery residents reviewed the ultrasound images. RESULTS: Thrombi associated with radiofrequency ablation demonstrated a greater degree of hypercellular response, fibroblastic reaction, and edema (3.42 vs 2.92; 3.75 vs 2.42; 2.83 vs 1.33). Specimens harvested from the iatrogenic-induced DVT swine demonstrated a more prolific response to trichrome staining (3.42 vs 2.67). Evidence of revascularization was found in all of the EHIT specimens but in 33% of DVT specimens. On the basis of histologic findings, the pathologist predicted correct modality 92% of the time. Subgroup analysis comparing paired specimens from each swine failed to demonstrate any marked pathologic differences. Recorded ultrasound images from EHIT and DVT samples were reviewed by fellows, residents, and vascular surgery staff to determine whether clot was stationary or free-floating (n = 111; 93%), evidence of retracted or adherent vein (n = 105; 88%), and absence of color flow (n = 102; 85%). The degree of occlusion (partial vs total) and degree of distention of a visualized vein were least likely to be agreed on by reviewers (n = 95; 79% each, respectively). In subgroup (DVT vs EHIT) analyses, the percentage agreement was greatest among vascular surgery fellows (89% and 92%) compared with residents (82% and 79%) and faculty (78% and 77%). CONCLUSIONS: It is possible to differentiate the thrombus origin on pathologic examination but not clinically on ultrasound. Wide variability exists for ultrasound diagnosis of EHIT and de novo DVT. Care must be taken in evaluating post-treatment duplex scans to not assign diagnosis of EHIT when DVT may well be present and extending into the deep venous system. The modulation of collagen production in the treatment of DVT may be helpful in preventing vascular dysfunction and reducing the post-thrombotic changes. Further studies on injury after radiofrequency ablation and laser ablation are needed.

Initial experience with HARMONIC FOCUS® inguinal exposure in endovascular aortic aneurysm repair.

BACKGROUND: An inguinal exposure provides adequate access to the femoral vessels, but with it comes risk of wound complications. Ultrasonic shears and blades have been shown to decrease complications in other anatomic dissections. There remains a paucity of literature on the usage of ultrasonic harmonic dissection techniques in the vascular surgery realm. This study depicts the initial experience using HARMONIC FOCUS(®) (HF) for inguinal exposure in both endovascular abdominal aortic aneurysm repair (EVAR) and thoracic endovascular abdominal aortic aneurysm repair (TEVAR) operations. METHODS: Patients who underwent an EVAR or a TEVAR operation with an open inguinal exposure during an 11-month period were included. RESULTS: Over the study period, 30 patients underwent an endovascular aortic aneurysm repair with open inguinal exposure; 25 patients had an EVAR and 5 patients underwent a TEVAR. Conventional electrocautery was used in 32 inguinal exposures and HF was used in 28. Six inguinal wounds developed postoperative complications in the study (10%). These occurred in 5 patients over a 4-month follow-up period. Conventional electrocautery dissection was used in 5 of the wounds (15.6%) and ultrasonic harmonic scalpel was used in 1 (3.6%). The complications consisted of 3 lymphocutaneous fistulas, 1 wound infection and 2 lymphoceles without fistula formation. CONCLUSIONS: We present the initial experience of HF dissection in inguinal exposure in a small population of patients who underwent EVAR and TEVAR. In this study, we demonstrate this technique may be associated with a lower incidence of postoperative wound complications when compared with conventional electrocautery inguinal exposure.

Transpalatal advancement pharyngoplasty for obstructive sleep apnea syndrome: results and analysis of failures.

OBJECTIVE: To assess the polysomnographic outcomes of patients with obstructive sleep apnea undergoing transpalatal advancement pharyngoplasty for retropalatal collapse and to compare responders with nonresponders to surgery. DESIGN: Retrospective medical record review. SETTING: Tertiary referral teaching hospital and private practice. PATIENTS: Sixty patients undergoing transpalatal advancement pharyngoplasty alone at a single sitting with preoperative and postoperative sleep studies were reviewed. INTERVENTION: Transpalatal advancement pharyngoplasty. MAIN OUTCOME MEASURES: Preoperative and postoperative polysomnographic data were analyzed and comparisons were assessed between responders and nonresponders. RESULTS: Following surgery, the mean (SD) respiratory disturbance index (RDI) decreased from 37.2 (20.4) to 15.4 (12.3), with an overall change of 21.8 (21.8) (95% confidence interval [CI], 16.2-27.4). Similarly, the mean (SD) arterial oxygen saturation nadir after transpalatal advancement pharyngoplasty surgery improved from 83.9% (5.4%) to 87.4% (4.3%), with an overall change of 3.5% (5.9%) (95% CI, 2.0%-5.0%). Between the traditional Gothic arch incision (n = 31) and the propeller incision (n = 29) an observed 31% (95% CI, 7%-51%) difference in success rate in favor of the latter was noted. CONCLUSIONS: Transpalatal advancement pharyngoplasty appears to be an effective and safe treatment option in selected patients. No preoperative variable was associated with surgical success in this study. The association of the propeller incision and surgical success requires further analysis.

The "Propeller" incision for transpalatal advancement pharyngoplasty: a new approach to reduce post-operative oronasal fistulae.

OBJECTIVE: To present a new soft tissue approach for transpalatal advancement pharyngoplasty (TPA), the propeller incision, and to compare the rates of post-operative oronasal fistula in those undergoing TPA with the traditional "Gothic Arch" incision described by Woodson and those with the propeller incision. METHODS: A prospectively maintained adult sleep apnoea surgery database was used to identify those patients undergoing TPA, either alone or in combination with other procedures, for obstructive sleep apnoea syndrome (OSAS) between February 2001 and September 2006 in a tertiary referral centre by a single surgeon (RHL). In addition to the incision used during TPA, patient demographic data, previous surgery of the upper airways, smoking history, pre-operative body mass index, respiratory disturbance index, oxygen saturation index and the occurrence of oronasal fistula post-operatively, were recorded. The propeller incision technique is described. RESULTS: A total of 89 patients who underwent TPA were identified. A total of 49 patients had a "Gothic Arch" incision and 40 had a "Propeller" incision. The two groups of patients were comparable in age, sex, previous tonsillar and uvulopalatopharyngoplasty surgery, smoking histories and pre-operative disease severity. In the "Gothic Arch" group, eight patients (16%) developed oronasal fistulae in the post-operative period versus only one patient (2.5%) in the "Propeller" group. The difference between the two groups was statistically significant (P=0.038, Fisher's exact test). Of the total cases with post-operative oronasal fistula (n=9), only one patient (from the Gothic Arch incision group) required operative closure which was performed under local anesthesia and healed without complication. CONCLUSION: The propeller incision provides an anatomically sensible axial-based flap that provides adequate access to perform TPA. It is associated with a lower incidence of oronasal fistula and is recommended by the authors.

Digital spectral analysis of the drill-bone acoustic interface during temporal bone dissection: a qualitative cadaveric pilot study.

HYPOTHESIS: To qualitatively assess the different acoustic signatures of an otologic drill burr-bone interface during temporal bone dissection on full thickness calvarial and thin tegmen bone. BACKGROUND: An appreciable change in the sound generated by drilling occurs with progressive thinning of the bone during temporal bone dissection. To date, descriptions of this phenomenon are limited to a handful of subjective characterizations. Using digital power spectral analysis, interpretation of complex functions of time such as acoustic signals can be interpreted. METHODS: Acoustic data recorded from five cadaveric temporal bone dissections were studied using digital spectral analysis. RESULTS: The energy bandwidth concentration was between 5.0 and 7.9 kHz for full thickness bone using the cutting burr. Thin tegmen bone bandwidth concentration was lower, between 3.7 and 7.4 kHz and 3.9 and 6.0 kHz, using cutting and diamond burrs, respectively. Harmonic frequencies for thin tegmen bone-burr signals were 630 Hz. CONCLUSION: There is a consistent, reproducible qualitative difference in the spectral domain of the acoustic signature from the drill burr-bone interface between thick calvarial bone and thin tegmen bone caused by a higher harmonic peak interval and lower energy bandwidth concentration in the thinned tegmen bone-burr interface signal thus concentrating the acoustic signal within a more optimal frequency range for human perception. These results allow for a better understanding of the perceived change in sound with progressive thinning of bone with drilling. In addition, these data may allow the development of more realistic acoustic interfaces in virtual reality temporal bone dissection simulators.

Obstructive sleep apnea, morbid obesity, and adenotonsillar surgery: a review of the literature.

Obstructive sleep apnea syndrome is a common occurrence in the obese pediatric population. As this subgroup is rapidly expanding, these children will be increasingly encountered by the otolaryngologist in practice. The literature regarding the etiology, pathogenesis, diagnosis and surgical treatment of obstructive sleep apnea in morbidly obese children is reviewed and pertinent data presented.

Cervicofacial emphysema and pneumomediastinum following pediatric adenotonsillectomy: a rare complication.

Cervicofacial emphysema and pneumomediastinum are rarely observed sequelae of surgical intervention in the upper aerodigestive tract. It is a potentially life-threatening condition but the majority of cases are self-limiting and benign. Symptoms include chest pain, neck pain, dyspnea and odynophagia. A case occurring after adenotonsillar surgery in a 7-year-old child is presented. This report highlights this unusual complication and its potential to delay the postoperative recovery following adenotonsillectomy.