Jeffrey Weinzweig

Metopic synostosis: Defining the temporal sequence of normal suture fusion and differentiating it from synostosis on the basis of computed tomography images.

Only the metopic suture normally fuses during early childhood; all other cranial sutures normally fuse much later in life. Despite this, metopic synostosis is one of the least common forms of craniosynostosis. The temporal sequence of normal physiologic metopic suture fusion remains undefined and controversial. Therefore, diagnosis of metopic synostosis on the basis of computed tomography images alone can prove misleading. The present study sought to determine the normal sequence of metopic suture fusion and characterize both endocranial and ectocranial suture morphology. An analysis of computed tomography scans of 76 trauma patients, ranging in age from 10 days to 18 months, provided normative craniofacial data that could be compared to similar data obtained from the preoperative computed tomography scans of 30 patients who had undergone surgical treatment for metopic synostosis. Metopic suture fusion was complete by 6 to 8 months in all nonsynostotic patients, with initiation of suture fusion evident as early as 3 months of age. Fusion was found to commence at the nasion, proceed superiorly in progressive fashion, and conclude at the anterior fontanelle. Although an endocranial ridge was not commonly seen in synostotic patients, an endocranial metopic notch was virtually diagnostic of premature suture fusion and was seen in 93 percent of synostotic patients. A metopic notch was not seen in any nonsynostotic patient. The morphologic and normative craniofacial data presented permit diagnosis of metopic synostosis based on computed tomography images obtained beyond the normal fusion period.

The fetal cleft palate: I. Characterization of a congenital model.

Any animal model of a human congenital anomaly established by iatrogenic methods involving intrauterine fetal manipulation has limited clinical applicability. A congenital model that more closely simulates the etiopathogenesis of a human anomaly may provide data that can more readily be extrapolated to that anomaly and, therefore, be used in diagnostic and management strategies. The present work provides a description and characterization of a congenital model of cleft palate in the goat. Palatal shelf closure normally occurs at approximately day 38 of gestation in the caprine species. Sixteen pregnant goats were gavaged twice daily during gestational days 32 through 41 [term, 145 days] with a plant slurry of Nicotiana glauca containing the piperidine alkaloid teratogen anabasine. Gross analysis and measurement of fetal clefts were performed at 60, 70, and 85 days gestation (four fetuses were studied at each time point). Seventeen clefted kids were sacrificed at specific intervals after birth (2 weeks, and 1, 3, and 6 months); after skull debridement and preparation, they were compared with 12 unclefted control kids. Complete clefting of the secondary palate occurred in 97 percent of the fetuses. In all cases, the cleft extended from the posterior aspect of the alveolar ridge to the uvula; the majority of these clefts were bilateral, with complete detachment of the vomer. Morphologically, these clefts were similar to human clefts. Eighteen percent of clefted newborn kids demonstrated gross maxillary hypoplasia and midfacial retrusion at birth with a relative Class III malocclusion. Direct measurement of the congenital caprine skulls confirmed these findings. The incidence of midfacial growth abnormalities in these clefted animals raises questions regarding the etiopathogenesis of facial dysmorphology that is unrelated to scarring of the maxilla. This congenital cleft palate model is currently being used to explore these questions and others related to craniofacial growth and palatal function after in utero repair.

Cranial vault expansion in the management of postshunt craniosynostosis and slit ventricle syndrome.

Background: Slit ventricle syndrome and postshunt craniosynostosis are uncommon complications after shunting procedures for congenital hydrocephalus. Slit ventricle syndrome occurs as a complication in 1 to 5 percent of patients after shunting procedures for hydrocephalus during infancy. These patients usually have had a shunt in place for years, with overdrainage of cerebrospinal fluid resulting in very small ventricles. Excessive intracranial decompression may result in ventricular collapse with the formation of slit-like ventricles and cranial vault collapse with secondary craniosynostosis. Methods: A retrospective review of 12 patients who had undergone cranial vault expansion for management of postshunt craniosynostosis and slit ventricle syndrome refractory to other treatment modalities was performed. All patients had initially been shunted for congenital hydrocephalus and subsequently underwent a mean of 4.9 shunt revisions before cranial vault expansion. Results: All 12 patients demonstrated decreased ventricular volume, with noncompliant slit-like ventricles in nine of these patients. Five patients demonstrated pancraniosynostosis, three patients demonstrated multiple sutural fusion, and isolated sagittal synostosis occurred in two patients. Two patients appeared to have “functional” synostoses with narrowed, overlapping sutures that were not actually fused. Eleven patients underwent bilateral fronto-orbital advancement with frontotemporoparietal expansion; one patient underwent only posterior vault expansion. Seven of the 12 patients required a mean of 2.3 shunt revisions after cranial vault expansion; five patients did not require subsequent revisions. Improvement in cranial vault shape was achieved in all 12 patients, as was improvement of neurologic symptoms in nine of the 12 patients. Conclusions: Cranial vault expansion is a useful approach in the management of the restricted cranium associated with slit ventricle syndrome and postshunt craniosynostosis. This approach resulted in a decreased need for shunt revisions and improvement of neurologic symptoms and cranial vault shape.

Silicon analysis of breast and capsular tissue from patients with saline or silicone gel breast implants : II. Correlation with connective-tissue disease

&NA; The silicone breast implant controversy rages on. Recent work has demonstrated that normal or baseline breast tissue silicon levels in women who had had no prior exposure to any type of breast implant may be as high as 446 &mgr;g/gm of tissue. These data ranged from 4 to 446 &mgr;g/gm of tissue, with a median of 27.0 &mgr;g/gm of tissue. In addition, numerous other epidemiologic and rheumatologic studies have demonstrated no association between silicone breast implants and any connective‐tissue diseases. Despite these reports, the use of silicone implants remains restricted. The present study measured breast and capsular tissue silicon levels from 23 breasts in 14 patients with saline implants, and from 42 breasts in 29 patients with silicone implants. No patient in the saline implant group presented with signs or symptoms of connective‐tissue disease. Patients with silicone implants, however, were divided into three groups based on the presence or absence of signs or symptoms of connective‐tissue disease: group I, no symptoms or signs; group II, + symptoms, no signs; and group III, + symptoms, + signs. Six patients in group III were diagnosed with a specific connective‐tissue disease, including systemic lupus erythematosus, rheumatoid arthritis, or scleroderma. The most common indications for implant removal or exchange were capsular contracture and implant rupture, although 41 percent of patients with silicone implants expressed media‐related concern over the implant issue. The most common symptoms described by patients in groups II and III were joint pain and stiffness, arm pain and numbness, and fatigue. In all groups, capsular tissue silicon levels were significantly greater than breast tissue levels. This finding may indicate that the capsule serves as a barrier to the distribution of silicone from the implant into adjacent breast tissue. Although breast tissue silicon levels in patients with silicone implants were not significantly greater than those in patients with saline implants (p = 0.48), capsular tissue levels in patients with silicone implants were, indeed, significantly greater than those in patients with saline implants (p < 0.001). However, no statistically significant differences in tissue silicon levels were observed with relation to the presence or absence of connective‐tissue disease signs or symptoms in patients with silicone implants (groups I to III). Therefore, these data strengthen the conclusion that there is no association between tissue silicon levels and connective‐tissue disease. (Plast. Reconstr. Surg. 101: 1836, 1998.)

Delayed cranial vault reconstruction for sagittal synostosis in older children: an algorithm for tailoring the reconstructive approach to the craniofacial deformity.

&NA; An algorithm for the management of sagittal synostosis in older children who underwent delayed cranial vault reconstruction is presented. This algorithm tailors the surgical approach to the specific craniofacial deformity present in each case. The scaphocephalic deformity characteristic of sagittal synostosis varies significantly when presentation is delayed beyond the first year of life, the time during which reconstruction is usually performed. Sixteen patients with sagittal synostosis who presented after 12 months of age, and were a mean of 3.2 years of age at the time of cranial vault reconstruction, were reviewed. Four patients demonstrated preoperative symptoms and objective findings indicative of increased intracranial pressure, including frequent headaches and emesis, papilledema, or digital markings on computed tomographic scan. Each of the 16 patients underwent either (1) single‐stage total vault reconstruction with or without concomitant fronto‐orbital expansion; (2) two ‐stage total vault reconstruction with anterior two‐thirds vault expansion followed by transverse occipital expansion and recession a mean of 8.7 months later; or (3) anterior two‐thirds vault reconstruction with or without frontoorbital expansion. In each case, the extent of the scaphocephalic deformity determined the procedure used. The presence of severe frontal bossing associated with transverse restriction of the orbitotemporal region was an indication for fronto‐orbital expansion in addition to vault reconstruction, whereas significant occipital protrusion was an indication for transverse posterior vault expansion and recession in addition to anterior two‐thirds vault reconstruction. Excellent aesthetic results were obtained in all cases regardless of the type of reconstruction performed. However, it is essential that the extent of the deformity be carefully evaluated preoperatively to permit selection of the appropriate technique for reconstruction. (Plast. Reconstr. Surg. 110: 397, 2002.)

The tic-tac-toe classification system for mutilating injuries of the hand

&NA; Several classifications of mutilating hand injuries exist in the literature. Unfortunately, each of these provides a categorization that is arbitrarily grouped according to the part of the hand predominantly involved. It is imperative that a comprehensive classification system incorporate the degree and precise location of soft‐tissue and/or bony destruction and the vascular integrity in addition to the predominantly involved part of the hand. We therefore devised a new classification system for mutilating injuries of the hand which categorizes them into seven types: (I) dorsal mutilation, (II) palmer mutilation, (III) ulnar mutilation, (IV) radial mutilation, (V) transverse amputations, (VI) degloving injuries, and (VII) combination injuries. These types are subcategorized into three subtypes: (A) soft‐tissue loss, (B) bony loss, and (C) combined tissue loss. Vascular integrity is recorded with subscript notation: (0) vascularization intact or (1) devascularization. The hand is then systematically divided into nine numerical zones in “tic‐tac‐toe” fashion with radial, central, and ulnar columns and proximal, central, and distal rows. The “TicTac‐Toe” classification system allows the examining surgeon to describe precisely any mutilating injury of the hand. This system permits accurate assessment of each hand injury by assignment of the appropriate classification type, subtype, vascular status, and zone involvement. Clinical examples illustrate the user‐friendliness and practicality of this new classification system. (Plast. Reconstr. Surg. 100: 1200, 1997.) The mutilated hand “has suffered a severe injury involving loss of substance, and…has been left…lacking in prehension.” D. A. Campbell Reid1 (1984)

Silicon analysis of breast and periprosthetic capsular tissue from patients with saline or silicone gel breast implants.

&NA; The ubiquitousness of silicon is well known. Recent work has demonstrated measurable baseline levels of silicon in nonaugmented cadavers, subsequent to numerous reports of significant elevations of such levels within patients with silicone breast implants and even more reports alleging a causal relation between silicone gel prostheses and connective‐tissue diseases. Despite the lack of scientifically substantiated data that such a relation exists, the calamitous silicone breast implant controversy has ensued. Saline‐filled breast implants are constructed with a silicone elastomer envelope that remains in direct contact with periprosthetic capsular tissue following implantation. Although there is no evidence to link saline implants with any disorders, it is important to know if saline breast implants contribute any silicon to human body baseline silicon levels. The present study measured tissue silicon levels in 28 breasts of 16 patients with saline‐filled implants to determine if the silicone envelope of these prostheses can contribute to the elevation of such levels. These data were compared with data from 116 breasts of 65 patients with silicone gel‐filled prostheses as well as breast tissue from 17 patients (controls) who had never been exposed to either type of implant. Samples of breast tissue and periprosthetic capsular tissue were obtained from patients with both intact and ruptured implants. Silicon levels of breast tissue specimens from patients with saline‐filled implants were within the range of the controls if the implants were intact. Silicon levels in periprosthetic capsular tissue from patients with intact saline‐filled implants were significantly higher than controls (p < 0.02); however, they were still 100‐fold less than capsular tissue levels from patients with intact gel‐filled implants. Silicon levels measured in both types of tissue were significantly elevated in patients with silicone gelfilled implants compared with controls (p < 0.01). In the case of ruptured gel implants, breast tissue demonstrated higher silicon levels than did similar specimens from patients with intact implants (p < 0.054); periprosthetic capsular tissue levels also were elevated, although the differences were not statistically significant (p = 0.54). These findings are independent of the implant brand or length of exposure to the particular prosthesis. The finding of elevated levels of silicon in both breast and periprosthetic capsular tissue in patients with silicone gel‐filled implants in no way implies or substantiates any claim of a causal relationship between silicone and any reported illnesses. (Plast. Reconstr. Surg. 98: 798, 1996.)

Long-term fate of transplanted autologous fat in a novel rabbit facial model.

Background: The concept of fat transplantation is not a new one in plastic surgery. Studies assessing fat graft viability following transplantation, however, have yielded conflicting observations. The present study evaluated the long-term fate of transplanted autologous fat using a novel facial augmentation model the authors have developed in the rabbit. Methods: Thirteen adult New Zealand White rabbits underwent fat harvest using a modified Coleman technique. The left upper lip was used as the recipient site; the right upper lip remained unaltered in each case. After harvest from the groin, 1 ml of adipose tissue was transplanted to the left upper lip of each rabbit. Rabbits were euthanized 1, 3, 6, and 12 months after unilateral lip augmentation. Coronal sections of both upper lips were evaluated histologically; the right upper lip served as an internal control in each case. Results: Histologic evaluation of specimens harvested at all postoperative time points demonstrated viable, transplanted fat graft in each case. Use of the nonoperated right lip allowed for paired evaluation of the experimental and control sides. A significant inflammatory response was present in the early phases, with evidence of neovascularization. Transplanted fat tissue was clearly visible in rabbits harvested 1 year postoperatively. Conclusions: The authors have established a novel, reproducible model with an internal control for long-term evaluation of transplanted fat. Histologic examination suggests an early inflammatory response to the injected fat followed by sequestration of nonviable tissue. The transplanted fat remained viable at 1 year, with good overall survivability and minimal fibrosis.

The fetal cleft palate: II. Scarless healing after in utero repair of a congenital model.

The role of fetal surgery in the treatment of non-life-threatening congenital anomalies remains a source of much debate. Before such undertakings can be justified, models must be established that closely resemble the respective human anomalies, and the feasibility and safety of these in utero procedures must be demonstrated. The authors recently described and characterized a congenital model of cleft palate in the goat. The present work demonstrates the methodology they developed to successfully repair these congenital cleft palates in utero, and it shows palatal healing and development after repair. A surgically created cleft model was developed for comparative purposes. Palatal shelf closure normally occurs at approximately day 38 of gestation in the caprine species. Six pregnant goats were gavaged twice daily during gestational days 32 to 41 (term, 145 days) with a plant slurry of Nicotiana glauca containing the piperidine alkaloid anabasine; the 12 fetuses had complete congenital clefts of the secondary palate. Repair of the congenital clefts was performed at 85 days of gestation using a modified von Langenbeck technique employing lateral relaxing incisions with elevation and midline approximation of full-thickness, bilateral, mucoperiosteal palatal flaps followed by single-layer closure. Six congenitally clefted fetuses underwent in utero repair, six remained as unrepaired controls. Twelve normal fetuses underwent surgical cleft creation by excision of a 20 x 3 mm full-thickness midline section of the secondary palate extending from the alveolus to the uvula, at 85 days of gestation. Six surgically clefted fetuses underwent concurrent repair of the cleft at that time; six clefted fetuses remained as unrepaired controls. At 2 weeks of age, no congenitally or surgically created clefts repaired in utero demonstrated gross or histologic evidence of scar formation. A slight indentation at the site of repair was the only remaining evidence of a cleft. At 6 months of age, normal palatal architecture, including that of mucosal, muscular, and glandular elements, was seen grossly and histologically. Cross-section through the mid-portion of the repaired congenitally clefted palates demonstrated reconstitution of a bilaminar palate, with distinct oral and nasal mucosal layers, after single-layer repair. In utero cleft palate repair is technically feasible and results in scarless healing of the mucoperiosteum and velum. The present work represents the first in utero repair of a congenital cleft palate model in any species. The use of a congenital cleft palate model that can be consistently reproduced with high predictability and little variation represents the ideal experimental situation. It provides an opportunity to manipulate specific variables, assess the influence of each change on the outcome and, subsequently, extrapolate such findings to the clinical arena with a greater degree of relevance.

The Fetal Cleft Palate : V. Elucidation of the Mechanism of Palatal Clefting in the Congenital Caprine Model

Background: Failure of palatal shelf fusion at the precise gestational time point when shelf elevation and migration normally occur results in clefting. The present study defined the mechanism of clefting in the congenital caprine model by evaluating the temporal sequence of palatal shelf fusion. Methods: Six Spanish-type goats pregnant with twins were gavaged for 10 days (gestational days 32 to 41) with anabasine. Goats were examined with ultrasound throughout this period to assess fetal movement and evaluated histologically. Twelve untreated, unclefted fetuses served as controls. Results: After anabasine induction, real-time ultrasound confirmed a dramatic decrease in fetal movement. Hyperflexion of the neck occurred throughout the experimental period compared with control fetuses, in which spontaneous neck movements occurred. Histologic evaluation of the induced fetuses demonstrated the tongue wedged between the palatal shelves throughout the period of fusion. The shelves remained vertically oriented without elevation, ultimately resulting in clefting. The unclefted, control group demonstrated progressive elevation and migration of the palatal shelves between gestational days 38 and 40, with contact and fusion of the medial edge epithelia in the midline. Conclusions: Palatal clefting in the congenital caprine model occurred concomitant with reduced fetal movement. Resultant neck hyperflexion causes the tongue to obstruct medial migration of the palatal shelves and fusion, whereas the shelves themselves are either directly prevented from elevation secondary to anabasine impairment or indirectly secondary to the obstructing tongue. Although the molecular mechanism for the teratogenic effects of anabasine remains elusive, the authors have demonstrated an association between reduced fetal movement and palatal clefting in their congenital caprine model.