Craniofacial distraction osteogenesis: a review of 3278 cases.

The nascent field of craniofacial distraction osteogenesis has not yet been subjected to a rigorous evaluation of techniques and outcomes. Consequently, many of the standard approaches to distraction have been borrowed from the experience with long bones in orthopedic surgery. The ideal "latency period" of neutral fixation, rate and rhythm of distraction, and consolidation period have not yet been determined for the human facial skeleton. In addition, because the individual craniofacial surgeon's experience with distraction has generally been small, outcomes and meaningful complication rates have not yet been published. In this study, a four-page questionnaire was sent to 2476 craniofacial and oral/maxillofacial surgeons throughout the world, asking about their experiences with distraction osteogenesis. Information about the types of cases, indications for surgery, surgical techniques, postoperative management, outcomes, and complications were tabulated. Of 274 respondents (response rate, 11.4 percent), 148 indicated that they used distraction in their surgical practice. One hundred forty-five completed surveys were entered into a database that provided information about 3278 craniofacial distraction cases. Statistical analyses were performed comparing the rates of premature consolidation, fibrous nonunion, and nerve injury, on the basis of the use of a latency period and different rates and rhythms of distraction. In addition, the rates of all complications were determined and compared on the basis of the number of distraction cases performed per surgeon. The results of the study clearly show a wide variation in the surgical practice of craniofacial distraction osteogenesis. Although the cumulative complication rate was found to be 35.6 percent, there is a pronounced learning curve, with far fewer complications occurring among more experienced surgeons (p < 0.001). The presence of inferior alveolar nerve injury as a result of mandibular distraction was much lower for respondents whose distraction regimens consisted of no more than 1 mm of distraction per day (19.5 percent versus 2.4 percent; p < 0.001). No evidence was found to support the use of a latency period or to divide the daily distraction regimen into more than one session per day. Conclusions could not be drawn from this study regarding the length of the consolidation period. Overall, the surgeon-reported outcomes are comparable with those published for other craniofacial procedures, despite the higher incidence of complications. Although conclusions made on the basis of a subjective questionnaire need to be interpreted cautiously, this study has strength in the large numbers of cases reviewed. Because of the anonymity of responses, it has been assumed that surgeons who responded to the survey reported accurate numbers of complications and successful outcomes. Finally, additional clinical and animal studies that will be of benefit in advancing the field of craniofacial distraction osteogenesis are outlined.

Standardizing digital photography: it's not all in the eye of the beholder.

Advances in digital photography have made it an efficient and economically appealing alternative to conventional photography. Nevertheless, as objective observers and clinical photographers, we must realize that all digital cameras are not created equal. Different digital cameras frequently used in plastic surgery practices (Olympus 600DL, Olympus 2500, Sony DSC-D700, Nikon Coolpix 950, and Nikon D1) were evaluated, using a subject photographed with each camera in the identical lighting conditions, to determine inherent differences in quality, color, and contrast of the resultant photographs. Three different lighting conditions were examined: single soft-box lighting, dual studio flash boxes, and operating room lighting with on-camera flash. The same digital settings (program mode, ISO camera default setting, high quality setting with JPEG compression) were used. Each camera was digitally color balanced using an 18 percent gray card. Raw and color-balanced images were viewed side-by-side. The macro-image capabilities of each camera were also examined. Conventional 35-mm photographs using a 105 macro-lens on Kodachrome and Ektachrome slide film were obtained for comparison. All of the digital cameras performed with noticeable differences, but they maintained consistency in the three different lighting conditions. Digital photographs differed most greatly with respect to quality and contrast, which was especially obvious once color balancing was performed. Marked differences in quality and ability were observed with respect to macro-image capabilities. Inherent differences in features among digital cameras produce dramatically different photographic results with regard to color, contrast, focus, and overall quality. With the increasing use of digital photography in plastic surgery journals and presentations, it must be recognized that digital cameras do not all display photographs of similar quality, especially when used to evaluate skin appearance. To standardize digital photography, the surgeon must realize that switching digital cameras is akin to switching film types. Standardization of digital photographs should include image resolution between 1.5 and 2.7 million pixels, ISO default setting, color balancing with an 18 percent gray card and software, consistency in focal distance, JPEG compression of medium-to-high quality, and backgrounds of medium blue or 18 percent gray.

Enzymatic activation associated with programmed fusion of the posterior interfrontal sutures in rats.

Fetal rat coronal sutures in culture undergo fusion in the absence of their dura mater. Coinciding with the period of fusion are marked cellular enzymatic changes. Alkaline phosphatase, a marker of osteoblastic activity, and tartrate-resistant acid phosphatase (TRAP), a marker of osteoclastic activity, both increase significantly within fusing sutures and indicate changes in the control of bone synthesis and breakdown. Other enzymes not specifically related to bone formation or degradation also show activation within these fusing sutures. These enzymes include tartrate-sensitive acid phosphatase (TSAP), a marker of lysosomal activity; hexokinase, a glycolytic enzyme; glucose 6-phosphate dehydrogenase (G6PD), an enzyme of the pentose monophosphate shunt; and glutathione reductase, an enzyme of the antioxidant pathway. In the present study, we compared the enzymatic changes previously seen ex vivo with those occurring in vivo during the programmed closure of the posterior interfrontal suture of the rat. This suture fuses between postnatal days 10 and 30 in the rat. The sagittal suture, which remains patent during this period, was used to establish baseline enzymatic activities in a comparable midline suture. Neonatal rats were killed at postnatal days 2, 4, 5, 8, 10, 12, 15, 20, and 30, and posterior interfrontal and sagittal sutures with bone plates on either side were removed. The suture regions of the samples were isolated, dura mater was removed, and suture regions were assayed by microanalytical techniques. Activities of alkaline phosphatase, TRAP, TSAP, hexokinase, G6PD, and glutathione reductase were measured. DNA content was also assayed, and enzyme activities were expressed per amount of DNA. Three pups were killed at each time point, and three to five assays were performed per suture (posterior interfrontal or sagittal) for each time point assayed. Alkaline phosphatase and TRAP activities showed marked increases in fusing sutures compared with nonfusing controls, similar to the increases demonstrated ex vivo. TSAP and hexokinase also showed elevations in the fusing posterior interfrontal sutures, with the greatest differences predominantly during the period of fusion, comparable to the changes seen ex vivo. However, G6PD and glutathione reductase, enzymes of the antioxidant pathway, did not demonstrate the same degree of activation seen ex vivo in fusing sutures. In fact, the levels were actually higher in the patent sagittal samples for the majority of time points examined. Alkaline phosphatase and TRAP activity elevations indicated both osteoblastic and osteoclastic activation during fusion, as seen in the ex vivo phenomenon. TSAP and hexokinase increases also reflected activation in lysosomes and in cellular metabolism during fusion, paralleling the ex vivo situation. However, a less clear pattern of activation in the antioxidant pathway, in contrast to the pattern seen ex vivo, was present. These differences may reflect the different environments of sutures in vivo and ex vivo. Alternatively, oxidative stress may play a more central role in the pathologic process of induced suture fusion ex vivo than in programmed suture fusion in vivo.

Prefabrication of combined composite (chimeric) flaps in rats.

The purpose of this study was to prefabricate a new combined composite (chimeric) flap that consists of four different tissues. The tissues were prefabricated around two independent pedicles that ultimately join as a single main pedicle. In the inguinal area of 36 rats, the saphenous and the superficial inferior epigastric (SIE) pedicles were dissected and prepared as vascular carriers. A fascial graft and a local muscle flap were wrapped around the saphenous pedicle. The SIE pedicle was then implanted under the abdominal skin to supply a future skin flap. An ear cartilage graft was also inserted under the abdominal skin and adjacent to the implanted SIE pedicle. After allowing 2-, 4-, 6-, and 12-week prefabrication periods in different groups of nine animals, the prefabricated tissues were raised around two pedicles nourished by the femoral pedicle and then transferred. Flap survival was assessed by observation, microangiography and histology. The skin flaps showed survival rates of 52 +/- 17% (mean +/- standard error of the mean), 64 +/- 16%, 86 +/- 11%, and 100 +/- 0% of the total areas in the 2-, 4-, 6-, and 12-week prefabricated flaps respectively. None of the control grafts that were prepared on the contralateral side survived totally. A significant difference was found between the 12- and 2-week (p < 0.008), 12- and 4-week (p < 0.02), and 6- and 2-week (p < 0.05) prefabrication groups. Histologically, fascial and cartilage grafts, and portions of muscle were viable in the 2- and 4-week groups. Also, noticeable necrosis was found in the skin flaps in these groups. The muscle showed mild (at 2, 4, and 6 weeks) and moderate (at 12 weeks) atrophy. After prefabrication for 6 weeks, all tissues demonstrated good survival. This study shows that a combined composite flap can be prefabricated successfully in rats after a 6-week period of prefabrication.

Giant plexiform neurofibroma of the back.

Complete excision of a giant neurofibroma can be technically difficult. Thorough preoperative planning with magnetic resonance imaging, computed tomography, and arteriography are indicated to define the extent of the mass and to facilitate operative planning. By following the treatment guidelines discussed in this case report, the authors feel that these tumors can be excised safely with minimal morbidity.

Converting to digital photography: a model for a large group or academic practice.

Digital photography has become an economical and efficient substitute for conventional photography. We recently converted our resident clinical photography to a digital format to make archiving more efficient and to save the costs of clinical photography. We present a model that can be applied to a large group or academic practice outlining the conversion of our clinical photography to digital format. We discuss the costs that we have incurred during the past 3 years of conventional photography, the economic benefit and costs for conversion to digital, and a 5-year projection of savings using digital photography. We also discuss the advantages of digital photography and the equipment needed for the conversion.

Osteoblastic and osteoclastic activation in coronal sutures undergoing fusion ex vivo.

Numerous studies have demonstrated the importance of dura mater in the normal development and regeneration of the cranium and its sutures. The purpose of this study was to analyze the effect of dura mater on the metabolism of bone during the process of premature suture fusion. Previously, coronal sutures of fetal rats have been shown to fuse in serum-free culture after removal of their dura mater, whereas sutures of neonatal rats resist fusion even without their dura mater present. Sutures from these two distinct developmental stages were evaluated by assaying alkaline phosphatase and tartrate-resistant acid phosphatase (TRAP), marker enzymes of bone synthesis and catabolism, respectively. Coronal sutures with adjacent calvaria were dissected from fetal day 19.5 (F19) rats (n = 142) and neonatal day 1 (N1) rats (n = 42) and randomly divided into two groups each: F19 sutures with dura mater intact; F19 sutures with dura mater removed; N1 sutures with dura mater intact; and N1 sutures with dura mater removed. Calvaria were grown in serum-free medium for up to 21 days, and enzyme activities in suture regions were assayed by microanalytical techniques at different time intervals of culture. F19 sutures without dura mater exhibited significant increases in enzyme activities during days 7 to 21 of culture, whereas those without dura mater did not. N1 sutures with or without dura mater exhibited no significant changes in enzyme activities during the 14-day period of culture. The process of F19 suture fusion, occurring in the absence of dura mater, coincided with the increased activities of both alkaline phosphatase and TRAP. These cellular, enzymatic changes may have implications for the cellular events comprising craniosynostosis in vivo.

Biocompatibility of fixation materials in the brain.

Recent clinical reports documenting passive intracranial translocation of microplates and microscrews have prompted concerns regarding brain biocompatibility and neurotoxicity of fixation hardware used in craniofacial surgery. Although the effects of commercially pure titanium. Vitallium (cobalt-chromium-molybdenum), stainless steel, and various alloys have been well assessed in bone and soft tissues, there are no comprehensive studies of these materials in the brain. To investigate this, the biocompatibility of titanium, vitallium, and 316L stainless steel was evaluated in the rabbit brain and compared with silicone elastomer shunt tubing, a material that is used commonly as a neurosurgical implant material with well-established brain biocompatibility. Forty-eight juvenile New Zealand White rabbits were randomly assigned to one of three groups and underwent placement of either commercially pure titanium microscrews, vitallium microscrews, or 316L monofilament stainless steel wire into the parietal region. Silicone elastomer strips of similar size were implanted in the contralateral hemisphere of each rabbit. Animals were assessed daily for signs of neurotoxicity. Rabbits in each group were sacrificed at 2, 4, 8, and 26 weeks following implantation. Brains were sectioned at the implantation site and were examined by means of standard hematoxylin and eosin stains and with immunohistochemical markers sensitive to inflammatory changes in the brain. None of the animals showed any behavioral changes or neurologic deficits suggestive of either systemic or localized toxicity from the implant materials. Silicone clastomer was found to cause the least amount of inflammation relative to other materials tested at all sacrifice points, suggesting that as a standard neurosurgical implant material, it is an appropriate control for studies of brain biocompatibility. At 2 weeks, titanium was found to cause the largest inflammatory response in surrounding brain parenchyma based on analysis of markers for microglial proliferation, gliosis, and leukocyte infiltration. At the 26-week endpoint of our study, the biocompatibility of titanium was nearly equal to the biocompatibility of vitallium based on all studied markers of inflammation. A progressive increase in the inflammatory response surrounding stainless steel implants was noted at 8 and 26 weeks. Relative to all materials studied, at 26 weeks the greatest leukocyte response was found with stainless steel implants. Our results indicate that at the 26-week end-point of our study, titanium and vitallium incited a similar inflammatory response in the rabbit brain that was greater than the response found with silicone elastomer, a standard neurosurgical implant material, but less than that found with stainless steel wire, which is commonly recommended as an alternative fixation material.

Iron-induced rat coronal suture fusion in vitro: the role of redox regulation.

The presumptive coronal sutures of rat fetuses at gestation days 19 and 20 have been shown to fuse prematurely when grown in the absence of dura mater in culture. In the present study, the representative enzymes of glucose metabolism and the antioxidative pathway were assayed during the process of suture fusion. The coronal sutures of fetal day 19.5 (F19) and neonatal day 1 rats were grown in the presence or absence of dura mater in serum-free culture. The enzymes assayed were hexokinase (HK) and pyruvate kinase (PK) of glycolysis, and glucose 6-phosphate dehydrogenase (G6PD) and glutathione reductase (GR) of the antioxidative pathway. F19 sutures cultured without dura mater, which fused, showed significant increases in enzyme activities over the preculture levels. HK increased by 200% to 300% of the preculture levels, G6PD by 400% to 500%, GR by 200%, and PK by 400% to 500%. The fetal sutures cultured with dura mater, which did not fuse, showed little alterations of HK, G6PD, and GR activities, but showed a significant 200% to 400% increase in PK activity. Neonatal sutures showed significant increases in enzyme activities during culture, but the presence of dura mater did not significantly affect enzyme activities. High activity levels of enzymes of the antioxidative pathway in F19 sutures coincided with the period of premature suture fusion. Treatment of fetal calvaria with prooxidant (induced by ferrous iron and ascorbic acid) produced suture fusion even in the presence of dura mater. Treatment with deferoxamine (an iron chelator and antioxidant) during the culture prevented suture fusion. The results suggest that fusing sutures experience increased biosynthetic demands and are placed under oxidative stress. When oxidative stress overwhelms the dural influence, the sutures undergo premature fusion.

Three-dimensional reconstruction of the human fetal philtrum.

The anatomy of the philtrum is incompletely understood because it is difficult to analyze three-dimensionally. Previous anatomic studies suggested that the philtral ridges are formed by the dermal insertion of the orbicularis oris muscle and musculis nasalis decussating across the midline, with the philtral dimple an area of few muscular insertions. This theory is inconsistent with the usual finding of a normal-appearing philtrum contralateral to the cleft in patients with unilateral cleft lip. Using a microcomputer and three-dimensional software, we have created a three-dimensional model of the philtrum from digitized images of sequential transverse histological sections from a third-trimester fetus. Our studies demonstrate that the philtral ridges are formed by thickened dermis and dermal appendages. The labial levators are the predominant muscles associated with the philtrum throughout its length; their fibers insert into the dermis lateral to the philtral ridges. Crossing muscle fibers of the orbicularis oris pars marginalis only appear below the vermilion-cutaneous junction, caudal to the philtral ridges.

Effects of deferoxamine on ischemia/reperfusion injury after peripheral nerve compression.

We have demonstrated previously that acute nerve compression produces ischemia/reperfusion injury in rat sciatic nerve. In this study, we evaluated the effects of deferoxamine, an antioxidant, on recovery from ischemia/reperfusion injury after nerve compression. The sciatic nerves of male Sprague-Dawley rats, 370 to 430 g, were subjected to 24 hours of compression with Silastic tubing. The control group received intravenous saline solution at the time of decompression. The therapeutic group received intravenous deferoxamine (50 mg per kilogram) at the time of removal of the Silastic tubing. Nerve tissues within and distal to the compression site were assayed for malondialdehyde (MDA) levels and for growth-associated protein 43 (GAP-43) expression, as markers of ischemia/reperfusion injury and nerve regeneration, respectively. In the control group (injury alone), the MDA levels were three times higher than normal during the initial 10 days and returned to normal by 14 days. In contrast, the deferoxamine treatment group had MDA levels that were not significantly different from precompression levels. In the control group, enhanced GAP-43 expression persisted until late in the recovery period. In the deferoxamine treatment group, the increased GAP-43 expression subsided early. The results suggest that the treatment of compressed peripheral nerve with deferoxamine at the time of surgical decompression reduces ischemia/reperfusion injury.

Etiopathogenesis of craniofacial anomalies.

This article reviews the current information available on the etiopathogenesis of craniofacial anomalies with a particular emphasis on craniosynostosis. The incidence of various types of craniosynostosis is presented, along with an overview of the causes of malformations and deformations. The basic development of cranial sutures and fusion is explored as a background for the exploration of advances in genetic and molecular biology. This information lays the foundation for our understanding of craniofacial deformities and their response to surgical treatment described in the the other articles of this issue.

Lambdoid synostosis.

Recent increases in presentation of occipital deformities have presented the craniofacial team with new challenges in diagnosis and treatment. As presented in this article, they appear to have a functional abnormality of the suture that results in a localized growth deformity. The growth inhibition in severe cases can result in changes in the local bone and brain, along with the entire skull and cranial base. Histologic analysis supports the theory that this is true lambdoid synostosis. Surgical correction is indicated in moderate to severe cases, and the authors have presented their technique and new data on outcomes.

Long-term results of flap reconstruction in median sternotomy wound infections.

Reconstruction of infected median sternotomy wounds using muscle and omental flaps has been shown to result in significantly reduced morbidity, mortality, and length of hospital stay. Despite these benefits, very little is known about the potential long-term sequelae of such procedures. The purpose of this study was therefore to evaluate the ultimate functional outcome in such patients. One-hundred and thirty-three consecutive patients underwent debridement and flap reconstruction of their infected median sternotomy wounds over an 8-year period. Eighty patients were available for follow-up and responded to a questionnaire. Forty-eight patients consented to a physical examination. The length of follow-up ranged from 15 to 108 months (average 48 months). Healed wounds were obtained in 99 percent of patients. Fifty-one percent of patients noted persistent pain or discomfort, particularly in the chest and shoulder. Forty-four percent noted areas of numbness/paresthesias, mainly on the chest. Thirty-four patients (42.5 percent) noted symptoms of sternal instability; of those consenting to an examination, 45 percent were confirmed to have instability. Twenty-six patients (32.5 percent) claimed postoperative weakness (shoulder/abdomen). Significant shoulder weakness was not demonstrated; however, abdominal weakness was substantial. Thirty-six percent of patients reported an inability to perform the same preoperative activities that were of importance to them (sports, housework, etc.). Of those patients eligible to return to work, 52 percent did not. Patients younger than age 60 had a somewhat higher chance of not returning to work. Scars were noted to be good to excellent in 75 percent, but contour abnormalities of the chest and abdomen were found in 85 percent.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of combined cold and hyperbaric oxygen storage on free flap survival.

We have previously reported that hyberbaric oxygen (HBO) improved the survival rate of experimental free flaps. The purpose of this study was to evaluate the effects of combined hypothermia and HBO administered during storage on free flaps and on the xanthine oxidase system in rats. Epigastric skin flaps were stored cold for 48 and 72 hours either in room air or under HBO (2.9 atmospheres absolute, 100% oxygen) before free flap transfer. The success rates of free flaps were 80% (8/10) after 48 hours and 20% (2/10) after 72 hours of cold storage in room air. HBO produced no effect after 48 hours but significantly increased the success rate to 70% (7/10) after 72 hours of cold storage. Tissue hypoxanthine (plus xanthine) levels increased to 210% of normal after 48 hours of cold storage in room air and to 176% in HBO. Elevated hypoxanthine levels returned toward normal by 72 hours of cold storage in room air, while the increased levels remained under HBO. Xanthine oxidase activities significantly increased by 60 to 80% during 72 hours of room air storage. HBO treatment inhibited xanthine oxidase activity to 48% of normal by 72 hours of storage. Free flaps exhibited no significant alterations in GR and G6PDH activity after 48 hours of cold storage in room air or HBO. After 72 hours of cold storage, the room air control displayed a trend of decreasing GR activity and a significant 20% decrease in G6PDH activity, while HBO groups showed no significant alterations in both GR and G6PDH activity compared to normal. Protection of the antioxidative enzymes by hypothermia and inhibition of the xanthine oxidase activity by HBO appear to be one of the mechanisms of improved skin flap survival in free flaps.

Flap tolerance to ischaemia in streptozotocin-induced diabetes mellitus.

The effects of diabetes mellitus (DM) on skin flap tolerance to 3 h of secondary venous ischaemia were evaluated. Epigastric island flaps were elevated 3, 6 and 12 weeks after induction of DM in rats. In the non-diabetic control groups, the flap survival was 85% in the 3-week group, 72% in the 6-week, and 78% in the 12-week. In untreated DM groups, the flap survival significantly decreased to 40% in the 3-week group, 25% in the 6-week, and 17% in the 12-week (P < 0.05 in all groups). Flap survival in the DM/insulin group decreased to 31% in the 3-week group. Effects of insulin therapy, however, were observed in later stages of DM: 71% and 62% survival in the 6- and 12-week group, respectively. Significant linear correlations between enzymatic responses and the flap survival were found. The results suggest that DM is detrimental to flap tolerance and is associated with the lack of metabolic responses to secondary ischaemia.

Microanalyses of enzymes and metabolites in ischemia/reperfusion-induced partial-thickness skin wounds.

A transition zone between well-perfused proximal tissue and inadequately perfused distal tissue was evaluated histologically and biochemically in skin flaps. Cranially based pedicle flaps, 3 x 7.5 cm, were made on the backs of female Sprague-Dawley rats. Flap survival was 22% of the original flap area at 7 days and 40% at 14 days after flap elevation (p < 0.001). The transition zone consisted of full-thickness skin survival proximally and partial-thickness wound distally. It is evident that skin wounds induced by ischemia or reperfusion repair continuously between 7 and 14 days after flap elevation. Tissue glucose, lactate, and hypoxanthine levels were measured to assess capillary perfusion in the transition zone on postoperative day 3. The proximal full-thickness skin 5 mm from the wound margin demonstrated no significant changes in glucose and lactate levels compared with normal skin. The partial-thickness wounds exhibited no change in glucose (a 33% decrease was not statistically significant) but a significant increase (319% of normal) in lactate level (p < 0.05). Hypoxanthine levels increased to 453% of normal in full-thickness skin (p < 0.01) and to 787% in partial-thickness wounds (p < 0.001). Metabolic response was evaluated by enzyme assays in the transition zone. Hexokinase activity increased by 251% of normal (p < 0.05), glucose 6-phosphate dehydrogenase by 245% (p < 0.01), and glutathione reductase by 184% (p < 0.05) in the proximal full-thickness skin. Hexokinase activity further increased by 482% of normal (p < 0.01), glucose 6-phosphate dehydrogenase by 379% (p < 0.05), and glutathione reductase by 346% (p < 0.01) in partial-thickness wounds. The results suggest that partial-thickness wounds have less capillary circulation but greater antioxidant enzyme activities than does the survival area with full-thickness skin.

Frameless stereotaxic integration of CT imaging data: accuracy and initial applications.

To evaluate the spatial accuracy of a rapid interactive method of transferring computed tomographic (CT) information between its display on a computer screen to its source (test object, operating field), a multidimensional computer combined with a six-jointed position-sensing mechanical arm was tested with a Plexiglas model consisting of 50 rods of varied height and known location, a plastic replica of the skull, and, subsequently, three patients. The median error value between image and real location was 1-2 mm (P > .95), regardless of the registration target sites. The accuracy, however, increased with the selection of widespread registration points, and 95% of all errors were below 3.70 mm (P > .95). The results compare favorably with the four most commonly used stereotaxic framed units. A misregistration error of 0.3-2.2 mm was found during intraoperative correlation between anatomy on the CT display and actual anatomic location in the operative field.