It is a pleasure to respond to this letter regarding the manuscript by Shaw and Kahn entitled “Aging of the Midface Bony Elements: A Three-Dimensional Computed Tomographic Study.”1 Shaw and Kahn, on the basis of analysis of facial computed tomographic scans of different age groups of individuals, suggested that continued bony remodeling may contribute to the signs of aging. Levine’s suggestion is that only longitudinal studies are capable of analyzing this type of shape analysis, which he believes shows the facial skeleton to remain stable with age.
I welcome his letter because it is very important to have an open discussion concerning controversies with regard to facial aging. Only through these discussions will our science continue to evolve, and the discussion is not academic: these concepts determine how we as surgeons approach the cosmetic surgery individual.
It seems as though the conventional thinking is that soft tissue is responsible for facial aging and that “bony remodeling” is a more recent idea or concept. Actually, history shows this to be otherwise. Hellman’s treatise states that “according to recent observations (Todd), bone continues to differentiate until senility.”2 Hellman also stated a basic premise, accepted and taken for granted today, that was extremely controversial when first presented: that bone continues to grow throughout life. One can gain insight into just how controversial this was by reading Northcroft’s critique.2
Rather than it being a “new” idea, Hellman was discussing continued differential growth of the facial skeleton 80 years ago. The principle of differential growth was also clearly described by Nanda in 1955.3 So the historic thinking is really that bone continues to remodel throughout life.
In the past, studies on facial growth have required longitudinal studies. The only reason is that the modern-day statistical analysis of shape did not yet exist. It required the genius of Fred L. Boostein, Ph.D., to essentially invent this new science. Past studies needed radiographs of the same individual at different ages in order to compare distances and angles.
Even modern-day growth experts know that angular measurements are simply invalid for studying growth, because the results can be interpreted in many ways. Say the angle of nasion–point A–menton increases in size. One can assume that the face has continued to increase in size, but an equally valid interpretation is that the nasion has receded and/or the menton has receded, leading to an increased angle. That is why studies with angular measurements do not carry any credibility these days. Add to this the potential inaccuracy of using the sella-nasion for positioning (these could have changed relative to one another) and the results can be very misleading (modern shape analysis eliminates the need for standardized positioning by using the procrustes transposition).
It is interesting to review the Bolton series data. I was invited to personally review the radiographs at Case Western Reserve Medical School a couple of years ago. This was fascinating. B. H. Broadbent, Jr., generously donated his time to help pull and review some of the older files. By superimposing the young and mature (at call back in the 1980s) traces, it was simply astounding to see how many small changes in shape and position had occurred. An article will be published from those data using the modern science of shape analysis.
Can this type of study be performed without longitudinal data? Almost certainly. It requires the use of specialized shape analysis. Ferrario et al. used a mesh grid with a procrustes transposition to show how differential growth occurs in the vertical dimension after the age of 30.4 Even more important was their finding of size-standardized shape differences in multiple facial regions.
One of the largest, multi-institutional studies of facial growth is currently underway. This is one of the most in depth studies to date, the results of which should certainly be of interest to both the researcher and the clinician.
It is a pleasure to discuss the topic of facial growth and aging. I have all the respect in the world for Dr. Levine. That controversy still exists regarding the basic mechanisms of facial aging just shows how much remains to be investigated.
Joel E. Pessa, M.D.
Department of Plastic Surgery
University of Texas Southwestern Medical Center
1801 Inwood Road
Dallas, Texas 75390-9132
1. Shaw, R. B., and Kahn, D. M. Aging of the midface bony elements: A three-dimensional computed tomographic study. Plast. Reconstr. Surg.
119: 675, 2007.
2. Hellman, M. Changes in the human face brought about by development. Int. J. Orthod. Oral Surg. Radiol.
20: 37, 1927.
3. Nanda, R. S. The rates of growth of several facial components measured from serial cephalometric roentgenograms. Am. J. Orthod.
41: 658, 1955.
4. Ferrario, V. F., Sforza, C., Serrao, G., Ciusa, V., and Dellavia, C. Growth and aging of the facial soft tissues: A computerized three-dimensional mesh diagram analysis. Clin. Anat.
16: 420, 2003.
Letters to the Editor, discussing material recently published in the Journal, are welcome. They will have the best chance of acceptance if they are received within 8 weeks of an article’s publication. Letters to the Editor may be published with a response from the authors of the article being discussed. Discussions beyond the initial letter and response will not be published. Letters submitted pertaining to published Discussions of articles will not be printed. Letters to the Editor are not usually peer reviewed, but the Journal may invite replies from the authors of the original publication. All Letters are published at the discretion of the Editor.
Authors will be listed in the order in which they appear in the submission. Letters should be submitted electronically via PRS’ enkwell, at www.editorialmanager.com/prs/.
We reserve the right to edit Letters to meet requirements of space and format. Any financial interests relevant to the content of the correspondence must be disclosed. Submission of a Letter constitutes permission for the American Society of Plastic Surgeons and its licensees and asignees to publish it in the Journal and in any other form or medium.
The views, opinions, and conclusions expressed in the Letters to the Editor represent the personal opinions of the individual writers and not those of the publisher, the Editorial Board, or the sponsors of the Journal. Any stated views, opinions, and conclusions do not reflect the policy of any of the sponsoring organizations or of the institutions with which the writer is affiliated, and the publisher, the Editorial Board, and the sponsoring organizations assume no responsibility for the content of such correspondence.