Assessing the Augmented Breast: A Blinded Study Comparing Round and Anatomical Form-Stable Implants

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1 Breast Surgery Assessing the Augmented Breast: A Blinded Study Comparing Round and Anatomical Form-Stable Implants Aesthetic Surgery Journal 2015, Vol 35(3) The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com DOI: /asj/sju053 Yazan Al-Ajam, MRCS; Dan J. Marsh, BSc, FRCS (Plast), PhD; Anita T. Mohan, BSc, MRCS; and Stephen Hamilton, MD, FRCS (Plast) Abstract Background: Controversy persists as to whether round or anatomical form-stable breast implants provide the most aesthetically pleasing results, and there is a paucity of evidence comparing cosmetic outcomes of these two implants. A blinded study comparing aesthetic outcomes was conducted in an attempt to address this issue. Objectives: The authors compare aesthetic outcomes between round and anatomical form-stable breast implants. Methods: Pre- and postoperative photographs of 60 consecutive patients undergoing breast augmentation (33 round, 27 anatomical) by a single surgeon were reviewed by 22 plastic surgeons. Photographs were graded on a modified Likert scale (1, poor; 4, excellent) for overall aesthetic result, upper pole contour, and natural appearance. The panel was asked to determine implant shape. Results: Anatomical implants scored higher for upper pole contour: anatomical 2.80 (±0.44 standard deviation) vs round 2.60 (±0.38). With regard to natural appearance and overall aesthetic results, anatomical implants scored higher: 2.89 (±0.42) vs 2.56 (±0.36) and 2.86 (±0.41) vs 2.72 (±0.37), respectively. None of these differences achieved statistical significance, and 62.7% of round and 49% of anatomical implants were correctly identified. There was no significant difference in the body mass index (BMI) between the 2 groups (P =.21). Conclusions: No significant difference (P >.05) in the general and specific cosmetic points between round and anatomical implants was demonstrated; many on the panel were unable to identify implant shape correctly. Both techniques seem to yield good cosmetic results. Clearly the decision on which implant to use must be made on an individual patient basis because many factors influence overall aesthetic outcome. Anatomical implants should not be assumed to produce a more natural result. Level of Evidence: 4 Accepted for publication August 29, Anatomical implants were first introduced in the early 1990s with the premise of providing the augmented breast with a more natural teardrop shape. 1 Generally, they are filled with highly cohesive silicone gel that helps to maintain shape and reduce the risk of leakage in the event of rupture (ie, formstable implants). They have been popularized by many surgeons 2-6 and are in wide use throughout Europe, although the use of gel-filled anatomical implants in the United States was restricted until 2006, when FDA approval was granted. 7 Controversy persists as to whether round or anatomical form-stable breast implants provide the most aesthetically Therapeutic pleasing results, and there is a paucity of evidence comparing the cosmetic outcome of the two implants. A blinded study comparing aesthetic outcomes of round and anatomical implants was conducted in an attempt to address Department of Plastic and Reconstructive Surgery, The Royal Free Hospital, London, UK. Corresponding Author: Yazan Al-Ajam, MRCS, Department of Plastic and Reconstructive Surgery, The Royal Free Hospital, Pond Street, London, NW3 2QG, UK. yazan.ajam@gmail.com

2 274 Aesthetic Surgery Journal 35(3) this issue. Current literature comparing aesthetic outcomes between the two implant shapes is reviewed, and the concept of the ideal breast is explored in the context of implant shape selection. METHODS The results of breast augmentation for 60 consecutive patients who underwent from April 2007 to August 2007 were analyzed. All patients had the procedure done for purely cosmetic purposes as a primary procedure and were operated on by the senior author (SH). Thirty-three patients had INSPIRA round cohesive gel implants and 27 had Inamed Style 410 cohesive gel anatomical implants of moderate height with moderate (MM) or full (MF) projection (Allergan Inc., Irvine, USA). Implants were placed in a dual-plane pocket through an inframammary incision. 8 Mean postoperative follow-up was 8 months. Data were collected on tissue pinch thickness and parity. On the whole, patients with thin upper pole tissues and little breast parenchyma were advised to consider anatomical implants if seeking a more natural appearance. Patients with thicker tissues were not particularly steered towards anatomical implants but could choose them if they wished. Pre- and postoperative photographs were reviewed and assessed by a panel of 22 plastic surgeons with experience in breast augmentation (14 male and 8 female). The experience of the panel ranged from 1 to 15 years (mean, 8.5), and all had knowledge in critically appraising the breast from an aesthetic perspective. Each patient had 6 photographs; 1 front and 2 lateral views for both pre- and postoperative state. Postoperative pictures were assessed a minimum of 6 months after surgery. The panel was asked to grade the photographs using a modified Likert scale. 9 Scores ranging from 1 (poor) to 4 (excellent) were given for overall aesthetic result, upper pole contour, and natural appearance. For upper pole contour, a gentle take off from the chest wall was deemed aesthetically more appealing than a convex shape, as this more closely resembled the natural breast shape. The panel was also asked to decide whether the implant used was round or anatomical. Both the investigators and the panel were blinded to the type of implant used. The results were tabulated in Microsoft Excel 2002 (Microsoft Corporation) and statistical analysis (χ 2 test.)was performed using SPSS 9.0 (SPSS Inc.). Body mass index (BMI), tissue pinch thickness, implant base diameter, and parity were measured for both groups and analyzed using an unpaired t-test. A P value <.05 was considered significant. (P =.261). With regard to natural appearance, the panel scored anatomical implants higher than round (2.89 ± 0.42 vs 2.56 ± 0.36), but again this did not achieve statistical significance (P =.304). Finally, for overall aesthetic results, anatomical implants scored 2.86 (±0.41), compared to round implants 2.72 (±0.37) (P =.442; Table 1, Figure1). The mean rate of correct identification of implants was 55.9% (62.7% round and 49.0% anatomical). Mean age in years in the round implant group was 32.8 (range, 19-57), with a mean BMI of 20.6 ( ). Mean implant size was 300 cc ( ), with a base diameter of 11.7 cm ( ) and tissue pinch thickness of 17 mm (6-39). Mean number of children ( parity) was 1.3 (0-4). For the anatomical implant group, mean age was 32.4 (18-41), with a mean BMI of 20.0 ( ). Mean implant size was 278 cc (range ), with a base diameter of 11.8 cm ( ) and tissue pinch thickness of 17 mm ( ). Mean parity was 0.9 (range 0-3). There was no significant difference in the BMI (P =.21), tissue pinch thickness (P =.87), implant base diameter (P =.45), or parity (P =.22) between the 2 groups. No patients had ptosis greater than grade I. Mean postoperative follow-up time was 8 months. No cases of capsular contracture were reported at final follow-up. Table 1. Summary of Scores: Mean ± Standard Deviation (1, poor; 4, excellent) Implant Type Upper Pole Natural Appearance Overall Aesthetics Anatomical 2.80 (±0.44) 2.89 (±0.42) 2.86 (±0.41) Round 2.60 (±0.38) 2.56 (±0.36) 2.72 (±0.37) P value RESULTS Anatomical form-stable implants scored higher for upper pole contour; 2.80 (±0.44 standard deviation) vs round 2.60 (±0.38), although this did not achieve significance Figure 1. Summary of scores for round vs anatomical implants.

3 Al-Ajam et al 275 DISCUSSION No significant difference in the general and specific cosmetic factors between round and anatomical form-stable implants was demonstrated in this study. Both techniques, when performed by an experienced surgeon, seem to yield good cosmetic results. Although anatomical implants scored slightly higher in all aesthetic categories, these failed to reach statistical significance. Although this could be attributed to the power of the study, it would be interesting to see if the results differ in a larger patient group. The panel was unable to accurately identify implant shape, even with access to pre- and postoperative photographs. Despite the surgeon s feeling that he was steering the patients toward choices (a confounding factor), objectively the two groups were very similar in the variables that were measured, with no statistically significant difference noted in BMI, tissue pinch thickness, or parity. Although large studies have shown good outcomes and patient satisfaction with anatomical implants, 2-6,10,11 there is still debate over whether these provide a better cosmetic outcome. Anatomical implants have been promoted for having a shape sympathetic to the natural contour of the breast, giving a more natural teardrop shape. By comparison, round implants may provide a less natural symmetrical projection. 12 In spite of this, the majority of surgeons on the panel were unable to accurately identify implant shape, a finding consistent with other studies. 10,13 This is particularly significant as the preoperative images were available to allow an informed assessment. A number of researchers have attempted studies to compare aesthetic outcomes of round and anatomical implants. 8,10,13,14 In a review of 100 patients who underwent gel-filled round or anatomical implants, Bronz reported excellent results with both types of implant and found it was nearly impossible to distinguish between the 2 types of implants using photographic evaluation. 10 However, these were simply the opinion of the author and were not subject to further scrutiny. In another subjective study of 30 augmentation patients selected from the best results of 2 surgeons, Friedman et al scored upper pole contour and natural appearance higher in round than anatomical implants, although with respect to breast beauty both achieved similar scores. 13 Tebbetts reviewed his experience with saline-filled anatomical implants and found they reduced upper shell collapse compared with saline-filled round implants and gave greater control in compensating for certain chest wall and parynchymal maldistribution deformities. 8 More recently, Cárdenas-Camarena and Encinas-Brambila reviewed their extensive experience of 932 patients who had bilateral breast implants (787 round and 145 anatomical). They concluded that good aesthetic results could be achieved with both implants. Although no attempt was made to objectively assess upper pole fullness or natural appearance, they did correlate the aesthetic outcome with the type of implant used and pre-existing breast and thoracic dimensions. They recommend the use of anatomical implants in patients with significant mammary asymmetry, small breast volume, or a prominent thorax, and for breasts with a significant deficit of inferior mammary volume. Round implants were more suited for patients who have a breast that will cover the implant, moderate breast pseudoptosis, and superior pole deficit. 14 There has been recent controversy concerning anatomical implants maintaining their shape in vivo. Hamas studied saline-filled round and anatomical implants in vivo using postoperative radiographs and concluded that both have similar teardrop proportions in the upright position, with round implants giving a more anatomical appearance in the recumbent position. 12,15 Nipshagen et al studied in vivo cohesive gel-filled round and anatomical breast implants using 3-dimensional magnetic resonance imaging scans. They demonstrated that both types largely maintain their original in vitro configuration. 16 Brody gives anecdotal evidence of implants excised with intact capsules having assumed shapes different from their original dimensions. 17 However, because all the implants used are likely to have been saline filled, the same might not necessarily apply to cohesive gel-filled implants. In addition to implant shape, the final aesthetic outcome of the augmented breast is dependent on the interaction of a multitude of factors. Tebbetts, a proponent of a formulaic approach to breast augmentation, identified more than 50 tissue and surgeon factors that can affect breast augmentation results. 18 The shape and contour of the thorax and pre-existing breast, surgical technique, skin thickness, compliance, and the healing process response to the implant can all affect the final outcome. We chose to place the implants in a dual-plane pocket, predominantly to increase the overlying tissue cover because most of our patients had a small amount of pre-existing breast tissue. Important factors to consider when deciding on the type of implant are the shape of the chest wall and breast volume. When a round implant is used in thin patients with small breasts, a round upper pole is achieved as the breast takes off from the thorax (Figure 2). In this case, an anatomical implant might give a smoother, more natural cephalad contour (Figure 3). Round implants are more forgiving when used in patients with adequate soft tissue coverage and greater pre-existing breast volume (Supplementary Figure S1). Our study has a number of limitations. Although they are based on the ideal breast shape taught to plastic surgeons, the assessment of breast aesthetics remain subjective, especially with regard to determining natural appearance of the breast, and it would be interesting to compare this with the preferred breast shape among the general public. Inclusion on the panel of a group of laypeople from a broad

4 276 Aesthetic Surgery Journal 35(3) Figure 2. Round implants in a 30-year-old thin patient give a prominent upper pole convexity. (A, C, E) Preoperative and (B, D, F) 6-month postoperative views. socioeconomic background will help to address the question of societal preferences, although this might bring with it its own problems with selection bias. A truly randomized study, of course, is not feasible, and a degree of selection bias by the surgeon is inevitable. Anatomical implants used were either MF or MM, and we would conclude, in this study at least, that these moderate- or full-projection anatomical implants make little difference in aesthetics as judged by the panel. Inclusion of implants with a more exaggerated anatomical shape might render them easier to identify in postoperative pictures. In this study all patients had dual-plane placement, and results may differ with implants in a subglandular position. However, on the whole, dual-plane placement is more popular than subglandular, thus it might be difficult to get a sufficient number of patients with subglandular implants performed by the same surgeon. It would be interesting to

5 Al-Ajam et al 277 Figure 3. Anatomical implants in a 24-year-old thin patient give a gentler take-off at the upper pole. (A, C, E) Preoperative and (B, D, F) 6-month postoperative views. compare results across a group of patients with similar BMIs, breast volumes, and upper pole tissue thicknesses. The study also looked at form-stable gel implants only. These results might not apply to standard silicone gel implants, which can change shape when the patient is upright due to gravity. A larger study looking at a range of body types, implant sizes, and pocket placement will at least partially address these points. CONCLUSIONS This study was unable to demonstrate a significant difference in aesthetic outcome between round and anatomical form-stable implants in a dual-plane setting. Both implant types yield equally good results and have their own application in selected patients. Despite considerable clinical experience, our panel was unable to correctly identify implant

6 278 Aesthetic Surgery Journal 35(3) shape in many cases. Neither implant is universally superior, although the more complex shape of anatomical implants allows for potentially greater manipulation of the aesthetic outcome in a wider range of breast shapes. For the majority of patients, good outcomes can be achieved with either implant type, though we would assert that for selected patients, implant type has a role to play in determining the final outcome. This study confirmed that most surgeons find it difficult to accurately distinguish between the two implants by physical appearance alone. With their greater cost and small risk of rotation, surgeons should be cautious in advising patients that anatomical implants impart a superior cosmetic result. Supplementary Material This article contains supplementary material located online at Disclosures The authors declared no potential conflicts of interest with respect to the research, authorship, and publication of this article. Funding The authors received no financial support for the research, authorship, and publication of this article. REFERENCES 1. Maillard G-F. McGhan style 410 anatomic breast implant. Plast Reconstr Surg. 1995;96: Fruhstorfer B-H, Hodgson E-L-B, Malata C-M. Early experience with an anatomical soft cohesive silicone gel prosthesis in cosmetic and reconstructive breast implant surgery. Ann Plast Surg. 2004;53: Hobar P-C, Gutowski K. Experience with anatomic breast implants. Clin Plast Surg. 2001;28: Niechajev I, Jurell G, Lohjelm L. Prospective study comparing two brands of cohesive gel breast implants with anatomic shape: 5-year follow-up evaluation. Aesthetic Plast Surg. 2007;31: Sadove R. Cohesive gel naturally-shaped breast implants. Aesthet Surg J. 2003;23: Valenti D, Desouches C, Jauffret J-L, et al. Anatomic breast implants in aesthetic and reconstructive surgery: report of 135 cases. Ann Chir Plast Esthet. 2007;52: Regulatory History of Breast Implants in the U.S. [U.S. Food and Drug Administration web site]. September 25, Available at: ProductsandMedicalProcedures/ImplantsandProsthetics/ BreastImplants/ucm htm. Accessed October 28, Tebbetts JB. Breast augmentation with full-height anatomic saline implants: the pros and cons. Clin Plast Surg. 2001;28: Norman G. Likert scales, levels of measurement and the laws of statistics. Adv Health Sci Educ Theory Pract. 2010;15: Bronz GA. Comparison of naturally shaped and round implants. Aesthet Surg J. 2002;22: Hedén P, Jernbeck J, Hober M. Breast augmentation with anatomical cohesive gel implants: the world s largest current experience. Clin Plast Surg. 2001;28: Hamas RS. The postoperative shape of round and teardrop saline-filled breast implants. Aesthet Surg J. 1999;19: Friedman T, Davidovitch N, Scheflan M. Comparative double blind clinical study on round versus shaped cohesive gel implants. Aesthet Surg J. 2006;26: Cárdenas-Camarena L, Encinas-Brambila J. Round gel breast implants or anatomic gel breast implants: which is the best choice? Aesthetic Plast Surg. 2009;33: Hamas RS. The comparative dimensions of round and anatomical saline-filled breast implants. Aesthet Surg J. 2000;20: Nipshagen MD, Beekman WH, Esmé DL, de Becker J. Anatomically shaped breast prosthesis in vivo: a change of dimension? Aesthetic Plast Surg. 2007;31: Brody GS. The perfect breast: is it attainable? Does it exist? Plast Reconstr Surg. 2004;113: Tebbetts JB. A system for breast implant selection based on patient tissue characteristics and implant-soft tissue dynamics. Plast Reconstr Surg. 2002;109: