Bony hump reduction is an integral part of classic

Rhinoplasty Nasal Hump Reduction With Powered Micro Saw Osteotomy INTERNATIONAL CONTRIBUTION Yakup Avşar, MD Background: Hump reduction with manual osteotomy is an invasive procedure in aesthetic rhinoplasty. Objective: We describe powered micro saw osteotomy as an effective alternative to manual hump removal. Methods: Powered micro saw osteotomy was performed to reduce the bony hump layer by layer to reach the intended level. The edges of the open roof were softened with a powered reciprocating rasp. Shielded burrs were used to remove minimal bony prominences as needed. Results: Between April 2005 and February 2007, the author performed 332 primary rhinoplasty and septorhinoplasty procedures. Hump reduction with powered micro saw osteotomy was performed in 259 cases, including 127 with moderate humps (3 to 4 mm), 112 with large humps (5 to 6 mm), and 20 with very large humps (7 to 8 mm). Satisfactory results were maintained in all cases, with minimal revision in 10 cases and no complications. Conclusions: Powered micro saw osteotomy provides a less invasive approach to bony hump reduction and prevents the multiple complications associated with manual osteotomies. (Aesthetic Surg J 2009;28:6 11.) Bony hump reduction is an integral part of classic rhinoplasty and is accomplished with precise execution of blunt force osteotomies. Overresection, asymmetry, and comminution are among the recognized complications of manual osteotomy that can occur even in the hands of practiced surgeons. Power-assisted instrumentation now offers a useful alternative for fine and controlled reduction of the bony hump. Recently, powered rasps have been successfully used in the case of minimal humps. 1-3 Powered micro saw osteotomy (PMSO) was used in cases of moderate, large, and very large humps. Using this novel system, it is possible to slice the bony hump in 2, 3, or even 4 layers. OPERATIVE TECHNIQUE The author performed 402 rhinoplasty and septorhinoplasty operations between April 2005 and February 2007. Secondary cases were eliminated from the study; a classification based on the amount of bony hump reduction in 332 consecutive primary cases was designed. Of these, 321 (96.7%) were performed using a closed approach. The amount of bony hump reduction was classified by assessing the difference between preoperative appearance and intended modifications of the nose at the level of the rhinion (Figure 1). Seven of the 332 cases needed no bony hump reduction; 66 had minimal bony humps (1 to 2 mm) that were managed with minimal powered rasping; 127 had moderate bony humps (3 Dr. Avşar is in private practice in Istanbul, Turkey. to 4 mm) that were managed with PMSO in 1 layer and minimal powered rasping for smoothing the edges of the open roof; 112 had large bony humps (5 to 6 mm) that were manipulated with PMSO in 2 layers and then treated by minimal rasping (Figure 2); and 20 had very large bony humps (7 to 8 mms) that were treated with PMSO in 3 or 4 layers and then minimal rasping. A surgical micromotor system (Bien-Air, Bienne, Switzerland) was used to cut and rasp the bone. The pliable irrigation complex of this system aids in cooling the site of osteotomy (Figure 3). A micro compass saw handpiece (Medicon eg, Tuttlingen, Germany) with a maximum speed of 20,000 RPM and a 2-mm stroke height was used in executing PMSO. Micro compass saw blades (18 and 22 mm; Medicon eg; Figure 4), a modified micro rasp head (Aesculap, Melsungen, Germany) and a shielded burr handpiece (Bien-Air) were used to sculpt the osseous vault (Figures 5 and 6). RESULTS Of the 259 patients undergoing PMSO, 249 obtained satisfactory refinement of the nasal dorsum after 1 operation (Figures 7 and 8). Ten patients required minimal surgical revision of the nasal dorsum because of small focal bony prominences. All of the revision cases achieved satisfactory surgical results with closed approach focal bone rasping. At average follow-up of 11 months (range, 6 to 28 months), there were no cases of delayed bone regrowth, bony dorsum irregularities, or other skin soft tissue complications. 6 Volume 29 Number 1 January/February 2009 Aesthetic Surgery Journal

3.5 mm Figure 2. Hump resection in 2 layers. Figure 1. Difference between the preoperative and intended nasal appearance at the level of the rhinion. Figure 3. Pliable irrigation system of the Bien-Air handpiece (Bienne, Switzerland). Figure 4. Micro saw blade. A B Figure 5. A, B, Intraoperative view of powered micro saw osteotomy with endonasal approach. Nasal Hump Reduction With Powered Micro Saw Osteotomy Volume 29 Number 1 January/February 2009 7

Figure 6. Minimal swelling and bruising at the end of 3-layered powered micro saw osteotomy. DISCUSSION Because blunt force osteotomies seldom permit fine and precise bone reduction, power-assisted instrumentation has become a desirable alternative to manual bone removal. 2 Various designs of micro saws, guarded burrs, drills, micro debriders, and reciprocating rasps are now commercially available for use in aesthetic and functional nasal surgery. 1-5 In classic rhinoplasty, after the completion of hump reduction with an osteotome, a sharp tungsten carbide rasp is used to soften the fracture edges. Alternatively, in some minor cases, the entire bony hump may be reduced with the rasp. 1 A tungsten carbide rasp is routinely used to smooth the margins of nasal bones comprising the open roof after hump reduction, but it is a traumatic instrument that produces dramatic swelling of the soft tissue cover of the nose, interfering with intraoperative assessments. 1,2 Guyuron 6 reported successful use of the shielded burr for deepening of the nasofrontal angle in the late 1980s. Becker, 1 Davis et al, 2 and Becker et al 7 all reported reduced trauma to the overlying soft tissues, smoother bone contour, and more precise bone reduction as advantages of powered instrumentation over the traditional nasal rasp when performing nasal bone removal. The authors also concluded that power-assisted bone removal was most helpful in cases where limited bone reduction was necessary, such as when treating small bony humps and minor deformities. 1,2,7 In cases requiring 1 to 2 mm of minimal bony hump reduction, rasping remains the best choice of instrumentation for vault refinement. It may be completed with or without medial and lateral osteotomies. In cases with moderate, large, and very large bony humps (requiring 3 to 8 mm of bone reduction), PMSO is a potent method for cutting the bone. This system allows resection of the bony dorsum under direct vision via an endonasal or external rhinoplasty approach. PMSO reciprocating blades with a 2-mm stroke height are less invasive alternatives to the Rubin osteotome for removal of the bony dorsum. These powered blades cut the bone precisely and in a controlled manner without fracturing the edges of bony hump. Unlike blunt force osteotomies that fracture the bone margins especially given the physical inconsistencies of human bone PMSO acts precisely according to the surgeon s planned line of osteotomy. Because brittle, asymmetric, or previously damaged nasal bones may behave unpredictably when subjected to blunt force impacts, even the experienced surgeon is likely to encounter the occasional osteotomy-related complication. 2 With the aid of the PMSO system, exact cutting movement along a predetermined path is not disrupted by areas of dense bone, which may divert the Rubin osteotome away from the desired cut and toward a plane of lesser resistance. This powered system is especially recommended for treating patients with attenuated bone strength, where the application of blunt force energy may fracture the weakened nasal bones. Such patients include those with previous nasal fractures, previous surgical osteotomies, or pathologic thinning of the nasal bones from aging, osteoporosis, or long-term steroid use. 8 Patients seeking revision rhinoplasty for contour deformities of the nasal bone are among the ideal candidates for this system. The most attractive advantage of PMSO is the opportunity to cut the dorsum layer by layer. In classic hump removal technique, if the amount of bone reduction is not sufficient after a Rubin osteotomy, performance of the second osteotomy involves a high risk of overresection and comminution; the remaining bone may be reduced only with the force of a tungsten carbide rasp that is highly traumatic to the soft tissue envelope. In every layer of PMSO, 1 to 2 mm of hump can be resected with minimal tissue loss. In cases with moderate hump, it is nececessary to resect 2 to 3 mm; this is executed with 1 layer of PMSO. The powered reciprocating fine rasp is ideal for smoothing the edges of the open roof after accomplishing the bone cut, and it reduces the vault by an additional 1 mm. For large humps, 4 to 5 mm of hump reduction is necessary and can be achieved with PMSO in 2 to 3 layers. It is possible to perform 3 or even 4 layers of osteotomy with fine cuts in the cases of very large humps (6 to 8 mm of bone removal). PMSO offers additional advantages in management of wide open roof and lateral nasal wall mobilization with precise medial, intermediate, and lateral osteotomies. Layered osteotomy makes it possible to control the amount of bone reduction between cuts, and asymmetries can be resolved with repeated fine resections. It is especially recommended in the case of a deviated and crooked nose where asymmetric resection of nasal bones is necessary. PMSO enables the practiced surgeon to perform fine bone cuts even in the case of closed rhinoplasty (Figure 5). The need for rasp use will be significantly diminished because the slicing will bring the hump level near to the ideal plan. 8 Volume 29 Number 1 January/February 2009 Aesthetic Surgery Journal

A B C D E F Figure 7. A, C, E, Preoperative views of a 24-year-old woman with a 3.5-mm nasal hump. B, D, F, Postoperative views 13 months after nasal hump reduction with powered micro saw osteotomy. Nasal Hump Reduction With Powered Micro Saw Osteotomy Volume 29 Number 1 January/February 2009 9

A B C D E F Figure 8. A, C, E, Preoperative views of a 22-year-old woman with a 5.5-mm nasal hump and a wide dorsoglabellar compartment. B, D, F, Postoperative views 28 months after nasal hump reduction with micro saw osteotomy. 10 Volume 29 Number 1 January/February 2009 Aesthetic Surgery Journal

The shielded burr is a proper choice for removing focal bone prominences without affecting the adjacent bone tissue. 7 Another advantage of the burr is its capability to do 3-dimensional refinement of dorsum structure after repositioning of bony sidewalls. Through use of PMSO and powered instrumentation, the amount of tissue swelling and ecchymosis was decreased dramatically in the intraoperative and postoperative periods (Figure 6). Another important advantage of powered instrumentation is fast healing; about 90% of the swelling resolves in 1 to 2 weeks. CONCLUSIONS PMSO can provide an alternative to manual osteotomy in the reduction of moderate to very large bony humps. This system is minimally invasive and sharply decreases the incidence of complications associated with manual procedures. Precise control in shaping the osseous vault enables the surgeon to predetermine the amount of bone reduction. DISCLOSURES The author has no financial interest in and received no compensation from manufacturers of products mentioned in this article. REFERENCES 1. Becker DG. The powered rasp: advanced instrumentation for rhinoplasty. Arch Facial Plast Surg 2002;4:267-268. 2. Davis RE, Raval J. Powered instrumentation for nasal bone reduction: advantages and indications. Arch Facial Plast Surg 2003;5:384 391. 3. Lopez MA, Westine JG, Toriumi DM. The role of powered instrumentation in rhinoplasty and septoplasty. J Long Term Eff Med Implants 2005;15:283 288. 4. Krouse JH. Endoscopic-powered rhinoplasty. J Otolaryngol 1999;28:282 284. 5. Raynor EM. Powered endoscopic septoplasty for septal deviation and isolated spurs. Arch Facial Plast Surg 2005;7:410 412. 6. Guyuron B. Guarded burr for deepening of nasofrontal junction. Plast Reconstr Surg 1989;84:513 516. 7. Becker DG, Toriumi DM, Gross CW, Tardy ME. Powered instrumentation for dorsal nasal reduction. Facial Plast Surg 1997;13:291 297. 8. Rohrich RJ, Hollier LH. Rhinoplasty with advancing age: characteristic and management. Clin Plast Surg 1999;23:281 296. Accepted for publication July 3, 2008. Reprint requests: Yakup Avşar, MD, ESTE Aesthetic Surgery Center, Levent cad. Ust zeren.sok No. 7 Villa 7, 1 Levent, Istanbul, Turkey. E-mail: yakupavsar@yahoo.com. Copyright 2009 by The American Society for Aesthetic Plastic Surgery, Inc. 1090-820X/$36.00 doi:10.1016/j.asj.2008.10.009 Nasal Hump Reduction With Powered Micro Saw Osteotomy Volume 29 Number 1 January/February 2009 11