Stability and function of RCL1 are dependent on the interaction with BMS1

During ribosome biogenesis, the small subunit (SSU) processome is responsible for 40S assembly. The BMS1/RCL1 complex is a core component of the SSU processome that plays an important role in 18S rRNA processing and maturation. Genetic studies using zebrafish mutants indicate that both Bms1-like (Bms1l) and Rcl1 are essential for digestive organ development. In spite of vital functions of this complex, the mutual dependence of these two nucleolar proteins for the stability and function remains elusive. In this study, we identified an RCL1-interacting domain in BMS1, which is conserved in zebrafish and humans. Moreover, both the protein stability and nucleolar entry of RCL1 depend on its interaction with BMS1, otherwise RCL1 degraded through the ubiquitination-proteasome pathway. Functional studies revealed that overexpression of RCL1 in BMS1-knockdown cells can partially rescue the defects in 18S rRNA processing and cell proliferation, and hepatocyte-specific overexpression of Rcl1 can resume zebrafish liver development in the bms1l substitution mutant bms1lsq163/sq163but not in the knockout mutant bms1lzju1/zju1, which is attributed to the nucleolar entry of Rcl1 in the former mutant. Our data demonstrate that BMS1 and RCL1 interaction is essential for not only pre-rRNA processing but also the communication between ribosome biogenesis and cell cycle regulation.

Loss-of-function of zebrafish cdt1 causes retarded body growth and underdeveloped gonads resembling human Meier-Gorlin syndrome

染色质许可和DNA复制因子1（Cdt1）是复制起始许可的主要调控因子，也是组成复制前复合物的核心成员。细胞通过依赖Cdt1的波动水平，且在每个周期中通过调节其总量以确保DNA仅复制一次。Cdt1功能缺陷会造成DNA过度复制，最终导致基因组不稳定。虽然酵母中cdt1 和人类Meier-Gorlin综合征（MGS）患者中的CDT1 已被广泛研究，但缺乏脊椎动物模型。我们发现在硬骨鱼类分支的几个鲤形目物种（包括斑马鱼）中，Cdt1蛋白在其N末端插入一段其他脊椎动物中没有的独特无序序列。通过分析在cdt1 基因中携带移码缺失的遗传性斑马鱼突变体（命名为cdt1zju1 ），我们发现突变胚胎虽然几乎无任何早期胚胎表型异常，但成年突变斑马鱼却表现出侏儒症、生存能力降低的症状，以及性腺发育不全且不育。此外，我们同样发现除转录本cdt1-201 外，斑马鱼还存在第二个cdt1 转录本——cdt1-202 ，它是通过跳过外显子2产生，这在其他生物中暂无报道。有意思的是cdt1-202 在cdt1-201 纯合突变体中显著上调。上述研究结果表明，cdt1-202 转录本可能可以补偿cdt1-201 在早期发育过程中的功能损失，但不能补偿后期生长，这可支持斑马鱼作为研究人类MGS的遗传模型。

Wdr5-mediated H3K4me3 coordinately regulates cell differentiation, proliferation termination, and survival in digestive organogenesis

Food digestion requires the cooperation of different digestive organs. The differentiation of digestive organs is crucial for larvae to start feeding. Therefore, during digestive organogenesis, cell identity and the tissue morphogenesis must be tightly coordinated but how this is accomplished is poorly understood. Here, we demonstrate that WD repeat domain 5 (Wdr5)-mediated H3K4 tri-methylation (H3K4me3) coordinately regulates cell differentiation, proliferation and apoptosis in zebrafish organogenesis of three major digestive organs including intestine, liver, and exocrine pancreas. During zebrafish digestive organogenesis, some of cells in these organ primordia usually undergo differentiation without apoptotic activity and gradually reduce their proliferation capacity. In contrast, cells in the three digestive organs of wdr5^-/- mutant embryos retain progenitor-like status with high proliferation rates, and undergo apoptosis. Wdr5 is a core member of COMPASS complex to implement H3K4me3 and its expression is enriched in digestive organs from 2 days post-fertilization (dpf). Further analysis reveals that lack of differentiation gene expression is due to significant decreases of H3K4me3 around the transcriptional start sites of these genes; this histone modification also reduces the proliferation capacity in differentiated cells by increasing the expression of apc to promote the degradation of β-Catenin; in addition, H3K4me3 promotes the expression of anti-apoptotic genes such as xiap-like, which modulates p53 activity to guarantee differentiated cell survival. Thus, our findings have discovered a common molecular mechanism for cell fate determination in different digestive organs during organogenesis, and also provided insights to understand mechanistic basis of human diseases in these digestive organs.

Nucleolar GTPase Bms1 displaces Ttf1 from RFB-sites to balance progression of rDNA transcription and replication

18S, 5.8S, and 28S ribosomal RNAs (rRNAs) are cotranscribed as a pre-ribosomal RNA (pre-rRNA) from the rDNA by RNA polymerase I whose activity is vigorous during the S-phase, leading to a conflict with rDNA replication. This conflict is resolved partly by replication-fork-barrier (RFB)-sites sequences located downstream of the rDNA and RFB-binding proteins such as Ttf1. However, how Ttf1 is displaced from RFB-sites to allow replication fork progression remains elusive. Here, we reported that loss-of-function of Bms1l, a nucleolar GTPase, upregulates rDNA transcription, causes replication-fork stall, and arrests cell cycle at the S-to-G2 transition; however, the G1-to-S transition is constitutively active characterized by persisting DNA synthesis. Concomitantly, ubf, tif-IA, and taf1b marking rDNA transcription, Chk2, Rad51, and p53 marking DNA-damage response, and Rpa2, PCNA, Fen1, and Ttf1 marking replication fork stall are all highly elevated in bms1l mutants. We found that Bms1 interacts with Ttf1 in addition to Rc1l. Finally, we identified RFB-sites for zebrafish Ttf1 through chromatin immunoprecipitation sequencing and showed that Bms1 disassociates the Ttf1‒RFB complex with its GTPase activity. We propose that Bms1 functions to balance rDNA transcription and replication at the S-phase through interaction with Rcl1 and Ttf1, respectively. TTF1 and Bms1 together might impose an S-phase checkpoint at the rDNA loci.

Rcl1 depletion impairs 18S pre-rRNA processing at the A1-site and up-regulates a cohort of ribosome biogenesis genes in zebrafish

Yeast Rcl1 is a potential endonuclease that mediates pre-RNA cleavage at the A₂-site to separate 18S rRNA from 5.8S and 25S rRNAs. However, the biological function of Rcl1 in opisthokonta is poorly defined. Moreover, there is no information regarding the exact positions of 18S pre-rRNA processing in zebrafish. Here, we report that zebrafish pre-rRNA harbours three major cleavage sites in the 5′ETS, namely –477nt (A′-site), –97nt (A₀-site) and the 5′ETS and 18S rRNA link (A₁-site), as well as two major cleavage regions within the ITS1, namely 208–218nt (site 2) and 20–33nt (site E). We also demonstrate that depletion of zebrafish Rcl1 mainly impairs cleavage at the A₁-site. Phenotypically, rcl1^–/– mutants exhibit a small liver and exocrine pancreas and die before 15 days post-fertilization. RNA-seq analysis revealed that the most significant event in rcl1^–/– mutants is the up-regulated expression of a cohort of genes related to ribosome biogenesis and tRNA production. Our data demonstrate that Rcl1 is essential for 18S rRNA maturation at the A₁-site and for digestive organogenesis in zebrafish. Rcl1 deficiency, similar to deficiencies in other ribosome biogenesis factors, might trigger a common mechanism to upregulate the expression of genes responsible for ribosome biogenesis.

Zebrafish hhex-null mutant develops an intrahepatic intestinal tube due to de-repression of cdx1b and pdx1

The hepatopancreatic duct (HPD) system links the liver and pancreas to the intestinal tube and is composed of the extrahepatic biliary duct, gallbladder, and pancreatic duct. Haematopoietically expressed-homeobox (Hhex) protein plays an essential role in the establishment of HPD; however, the molecular mechanism remains elusive. Here, we show that zebrafish hhex-null mutants fail to develop the HPD system characterized by lacking the biliary marker Annexin A4 and the HPD marker sox9b. The hepatobiliary duct part of the mutant HPD system is replaced by an intrahepatic intestinal tube characterized by expressing the intestinal marker fatty acid-binding protein 2a (fabp2a). Cell lineage analysis showed that this intrahepatic intestinal tube is not originated from hepatocytes or cholangiocytes. Further analysis revealed that cdx1b and pdx1 are expressed ectopically in the intrahepatic intestinal tube and knockdown of cdx1b and pdx1 could restore the expression of sox9b in the mutant. Chromatin-immunoprecipitation analysis showed that Hhex binds to the promoters of pdx1 and cdx1b genes to repress their expression. We therefore propose that Hhex, Cdx1b, Pdx1, and Sox9b form a genetic network governing the patterning and morphogenesis of the HPD and digestive tract systems in zebrafish.

rDNA subtypes and their transcriptional expression in zebrafish at different developmental stages

Eukaryotic 18S, 5.8S and 28S rRNAs are processed from a single transcript transcribed from the 45S rDNA gene, which is normally tandemly arrayed over hundred copies in a genome. Recently, a maternal (M) subtype and a somatic (S) subtype of rDNA were identified in zebrafish, with M-subtype on chromosome 4 and S-subtype on chromosome 5. It appears that the M-subtype is only expressed in eggs whilst the expression of the S-subtype is coupled with the initiation of zygotic gene expression. In this report, we identified three novel but transcriptionally inactive 18S variants in zebrafish genome with chromosome location different from the M- and S-subtype, suggesting translocation of 18S rDNA fragment during zebrafish evolution. Furthermore, we confirmed that the unfertilized eggs only have the M-subtype transcripts while brain, heart and liver have only the S-subtype transcripts. Both the M- and S-subtype transcripts were detected in female gonad. Our results support that the expression of different subtypes of rDNA is differentially regulated to meet the requirement for 'specialized ribosomes' during different developmental stages.

Sas10 controls ribosome biogenesis by stabilizing Mpp10 and delivering the Mpp10-Imp3-Imp4 complex to nucleolus

Mpp10 forms a complex with Imp3 and Imp4 that serves as a core component of the ribosomal small subunit (SSU) processome. Mpp10 also interacts with the nucleolar protein Sas10/Utp3. However, it remains unknown how the Mpp10-Imp3-Imp4 complex is delivered to the nucleolus and what biological function the Mpp10-Sas10 complex plays. Here, we report that the zebrafish Mpp10 and Sas10 are conserved nucleolar proteins essential for the development of the digestive organs. Mpp10, but not Sas10/Utp3, is a target of the nucleolus-localized Def-Capn3 protein degradation pathway. Sas10 protects Mpp10 from Capn3-mediated cleavage by masking the Capn3-recognition site on Mpp10. Def interacts with Sas10 to form the Def-Sas10-Mpp10 complex to facilitate the Capn3-mediated cleavage of Mpp10. Importantly, we found that Sas10 determines the nucleolar localization of the Mpp10-Imp3-Imp4 complex. In conclusion, Sas10 is essential not only for delivering the Mpp10-Imp3-Imp4 complex to the nucleolus for assembling the SSU processome but also for fine-tuning Mpp10 turnover in the nucleolus during organogenesis.

Centrosomal protein FOR20 is essential for cilia-dependent development in zebrafish embryos

Centrosomal proteins play critical roles in ciliogenesis. Mutations in many centrosomal proteins have been documented to contribute to developmental defects and cilium-related diseases. Centrosomal protein fibroblast growth factor receptor 1 oncogene partner-related protein of 20 kDa (FOR20) is crucial for ciliogenesis in mammalian cells and the unicellular eukaryote Paramecium; however, the biologic significance of FOR20 in vertebrate development remains unclear. We cloned the zebrafish homolog of the for20 gene and found that for20 mRNA is enriched in ciliated tissues during early zebrafish development. Knockdown of for20 by morpholino oligonucleotides in zebrafish results in multiple ciliary phenotypes, including curved body, hydrocephaly, pericardial edema, kidney cysts, and left-right asymmetry defects. for20 morphants show reduced number and length of cilia in Kupffer's vesicle and pronephric ducts. High-speed video microscopy reveals that cilia in most for20 morphants are consistently paralyzed or beat arrhythmically. To confirm the ciliary phenotypes of for20 morphants, we used the CRISPR/Cas9 system to disrupt for20 gene in zebrafish. for20 mutants exhibit multiple ciliary phenotypes resembling the defects in for20 morphants. All of these phenotypes in for20 morphants and mutants are significantly reversed by exogenous expression of for20 mRNA. Taken together, these data suggest that FOR20 is required for cilium-mediated processes during zebrafish embryogenesis.-Xie, S., Jin, J., Xu, Z., Huang, Y., Zhang, W., Zhao, L., Lo, L. J., Peng, J., Liu, W., Wang, F., Shu, Q., Zhou, T. Centrosomal protein FOR20 is essential for cilia-dependent development in zebrafish embryos.

The genetic diversity and population structures of indigenous pig breeds in Zhejiang Province revealed by GGRS sequencing

Chinese indigenous pigs in Zhejiang Province are well known for their high fecundity. In order to verify breed subdivision at the genomic level, we investigated genetic diversity and population structure of seven breeds and made comparisons with three Western pig breeds using next-generation sequencing data. Parameters obtained from allelic richness and proportion of polymorphic markers indicated that the genetic diversity of the Chinese indigenous pigs was higher than that of the Western pigs, with the highest and lowest values found in the Chaluand and the Landrace pigs respectively. Both neighbor-joining tree and principal components analysis could distinguish breeds from one another and structure analysis showed less differentiation among Western pigs than among the Chinese pigs. The average linkage disequilibrium decay over distance was significantly less in the Chinese pigs compared with the Western pigs, ranging from 188.2 to 280.6 kb for the Chinese pigs and 680.3 to 752.8 kb for the Western breeds and showing an average r² threshold value of 0.3. Results obtained from high-density SNP comparison over the whole genome on genetic diversity and population structure were in agreement with the current breed classification of the pigs in Zhejiang Province. More importantly, the results presented here advances our current understanding of the genomic biology of Chinese indigenous pigs in Zhejiang Province and allows for implementation of conservation strategies in additional breeds.

Phosphorylation of Def Regulates Nucleolar p53 Turnover and Cell Cycle Progression through Def Recruitment of Calpain3

Digestive organ expansion factor (Def) is a nucleolar protein that plays dual functions: it serves as a component of the ribosomal small subunit processome for the biogenesis of ribosomes and also mediates p53 degradation through the cysteine proteinase calpain-3 (CAPN3). However, nothing is known about the exact relationship between Def and CAPN3 or the regulation of the Def function. In this report, we show that CAPN3 degrades p53 and its mutant proteins p53A138V, p53M237I, p53R248W, and p53R273P but not the p53R175H mutant protein. Importantly, we show that Def directly interacts with CAPN3 in the nucleoli and determines the nucleolar localisation of CAPN3, which is a prerequisite for the degradation of p53 in the nucleolus. Furthermore, we find that Def is modified by phosphorylation at five serine residues: S50, S58, S62, S87, and S92. We further show that simultaneous phosphorylations at S87 and S92 facilitate the nucleolar localisation of Capn3 that is not only essential for the degradation of p53 but is also important for regulating cell cycle progression. Hence, we propose that the Def-CAPN3 pathway serves as a nucleolar checkpoint for cell proliferation by selective inactivation of cell cycle-related substrates during organogenesis.

Distinctive genes determine different intramuscular fat and muscle fiber ratios of the longissimus dorsi muscles in Jinhua and landrace pigs

Meat quality is determined by properties such as carcass color, tenderness and drip loss. These properties are closely associated with meat composition, which includes the types of muscle fiber and content of intramuscular fat (IMF). Muscle fibers are the main contributors to meat mass, while IMF not only contributes to the sensory properties but also to the plethora of physical, chemical and technological properties of meat. However, little is known about the molecular mechanisms that determine meat composition in different pig breeds. In this report we show that Jinhua pigs, a Chinese breed, contains much higher levels of IMF than do Landrace pigs, a Danish breed. We analyzed global gene expression profiles in the longissimus dorsi muscles in Jinhua and Landrace breeds at the ages of 30, 90 and 150 days. Cross-comparison analysis revealed that genes that regulate fatty acid biosynthesis (e.g., fatty acid synthase and stearoyl-CoA desaturase) are expressed at higher levels in Jinhua pigs whereas those that regulate myogenesis (e.g., myogenic factor 6 and forkhead box O1) are expressed at higher levels in Landrace pigs. Among those genes which are highly expressed in Jinhua pigs at 90 days (d90), we identified a novel gene porcine FLJ36031 (pFLJ), which functions as a positive regulator of fat deposition in cultured intramuscular adipocytes. In summary, our data showed that the up-regulation of fatty acid biosynthesis regulatory genes such as pFLJ and myogenesis inhibitory genes such as myostatin in the longissimus dorsi muscles of Jinhua pigs could explain why this local breed produces meat with high levels of IMF.

Sec13 safeguards the integrity of the endoplasmic reticulum and organogenesis of the digestive system in zebrafish

The Sec13-Sec31 heterotetramer serves as the outer coat in the COPII complex, which mediates protein trafficking from the endoplasmic reticulum (ER) to the Golgi apparatus. Although it has been studied in depth in yeast and cultured cells, the role of COPII in organogenesis in a multicellular organism has not. We report here that a zebrafish sec13(sq198) mutant, which exhibits a phenotype of hypoplastic digestive organs, has a mutation in the sec13 gene. The mutant gene encodes a carboxyl-terminus-truncated Sec13 that loses its affinity to Sec31a, which leads to disintegration of the ER structure in various differentiated cells in sec13(sq198), including chondrocytes, intestinal epithelial cells and hepatocytes. Disruption of the ER structure activates an unfolded protein response that eventually causes the cells to undergo cell-cycle arrest and cell apoptosis, which arrest the growth of developing digestive organs in the mutant. Our data provide the first direct genetic evidence that COPII function is essential for the organogenesis of the digestive system.

liver-enriched gene 1a and 1b encode novel secretory proteins essential for normal liver development in zebrafish

liver-enriched gene 1 (leg1) is a liver-enriched gene in zebrafish and encodes a novel protein. Our preliminary data suggested that Leg1 is probably involved in early liver development. However, no detailed characterization of Leg1 has been reported thus far. We undertook both bioinformatic and experimental approaches to study leg1 gene structure and its role in early liver development. We found that Leg1 identifies a new conserved protein superfamily featured by the presence of domain of unknown function 781 (DUF781). There are two copies of leg1 in zebrafish, namely leg1a and leg1b. Both leg1a and leg1b are expressed in the larvae and adult liver with leg1a being the predominant form. Knockdown of Leg1a or Leg1b by their respective morpholinos specifically targeting their 5′-UTR each resulted in a small liver phenotype, demonstrating that both Leg1a and Leg1b are important for early liver development. Meanwhile, we found that injection of leg1-ATG^MO, a morpholino which can simultaneously block the translation of Leg1a and Leg1b, caused not only a small liver phenotype but hypoplastic exocrine pancreas and intestinal tube as well. Further examination of leg1-ATG^MO morphants with early endoderm markers and early hepatic markers revealed that although depletion of total Leg1 does not alter the hepatic and pancreatic fate of the endoderm cells, it leads to cell cycle arrest that results in growth retardation of liver, exocrine pancreas and intestine. Finally, we proved that Leg1 is a secretory protein. This intrigued us to propose that Leg1 might act as a novel secreted regulator that is essential for liver and other digestive organ development in zebrafish.

The craniofacial anomalies archive at St. Louis Children's Hospital: 20 years of craniofacial imaging experience

This article describes how the Craniofacial Imaging Laboratory at the Cleft Palate and Craniofacial Deformities Institute, St. Louis Children's Hospital, Washington University Medical Center, has developed an electronic archive for the storage of computed tomography image digital data that is independent of scanner hardware and independent of units of storage media (i.e., floppy disks and optical disks). The archive represents one of the largest repositories of high-quality computed tomography data of children with craniofacial deformities in the world. Archiving reconstructed image data is essential for comparative imaging, surgical simulation, quantitative analysis, and use with solid model fabrication (e.g., stereolithography). One tertiary craniofacial center's experience in the establishment and maintenance of such an archive through three generations of storage technology is reported. The current archive is housed on an external 35-GB hard drive attached to a Windows-based desktop server. Data in the archive were categorized by specific demographics into groups of patients, number of scans, and diagnoses. The Craniofacial Imaging Laboratory archive currently contains computed tomography image digital data for 1827 individual scans. The earliest scan was done in 1980; the most recently stored scan for the purposes of this report occurred in May of 2000. The average number of scans archived per complete year was 94, with a range of 59 to 138. Of the 1827 total scans, 74 percent could be classified into specific diagnostic categories. The majority of the archive (55 percent) is composed of the following five diagnoses: sagittal synostosis (17 percent), unilateral coronal synostosis (11 percent), hemifacial microsomia (10 percent), plagiocephaly without synostosis (10 percent), and metopic synostosis (7 percent). Storage of computed tomography image data in a digital archive currently allows for continuous upgrading of image display and analysis and facilitates longitudinal and cross-sectional studies, both intramural and extramural. Internet access for clinical and research purposes is feasible, but contingent on protection of patient confidentiality. The future of digital imaging regarding craniofacial computed tomography scan storage and processing is also discussed.

Craniofacial surgical simulation: application of three-dimensional medical imaging and rapid prototyping models

BACKGROUND

Adequate assessment of the deformity, formulation of good treatment planning, and sufficient rehearsal of procedures before actually performing surgery ensure successful craniofacial surgery. Three-dimensional computed tomography (CT) imaging and facsimile models were used in combination to evaluate their function in craniofacial surgery.

METHODS

Three-dimensional imaging and facsimile models were used for reconstruction of craniofacial deformity. CT data were acquired, processed, and reconstructed to display 3-dimensional images. The images were used for evaluation of the deformity. The images were then manipulated to create multiple osseous objects. Surgical simulation was performed by moving the computer images. The image processing and manipulation were achieved using the AnalyzePC program. The raw CT data were transformed into a readable format and transferred to produce facsimile models using rapid prototyping technology. The skull models were used for evaluation and surgical simulation. Both methods were compared and used to assist in surgery, which was performed according to the simulations.

RESULTS

Three-dimensional CT imaging and facsimile models were helpful for simulation of craniofacial surgery. The actual surgery results were satisfactory without complications. Particular advantages were the unlimited trials with the imaging method, and the feeling of reality with the model method.

CONCLUSIONS

Craniofacial surgery is facilitated by preoperative simulation of procedures. Both 3-dimensional CT imaging and facsimile models are helpful for craniofacial surgical simulation.

The course of the inferior alveolar nerve in the normal human mandibular ramus and in patients presenting for cosmetic reduction of the mandibular angles

This study was undertaken to quantify the path of the inferior alveolar nerve in the normal human mandible and in the mandibles of patients presenting for cosmetic reduction of the mandibular angles. The goals were: (1) to provide normative information that would assist the surgeon in avoiding injury to the nerve during surgery; (2) to characterize gender differences in the normal population; and (3) to compare the course of the nerve in the normal population to its course in a group of patients who presented with a complaint of "square face." The study was based upon the computerized tomographic scans of 10 normal patients (six men, four women) and 8 patients (all women) complaining of "square face." Using AnalyzePC 2.5 imaging software, the mandibles were segmented and the position of the nerve was recorded within its osseous canal in the mandibular ramus on each axial slice in which it was identifiable. Distances were calculated between the nerve and the anterior, posterior, lateral, and medial cortices. The positions of the lateral ramus prominence and the lowest point on the sigmoid notch were also recorded. The position of the mental foramen was recorded in relation to the nearest tooth, and the three-dimensional surface distances from the foramen to the alveolar bone, the inferior border of the mandible, and the mandibular symphysis were determined. The distances from the entrance of the nerve into the mandible to the lateral ramus prominence and the lowest point on the sigmoid notch were calculated. Summary statistics were obtained, comparing differences in gender. The nerve was identifiable in each ramus over a mean distance of 12.7 mm. On average, the lateral ramus prominence was 0.3 mm higher on the caudad-cephalad axis than the point at which the nerve entered the bone, whereas the location of the lowest point on the sigmoid notch was 16.6 mm above the nerve. The average distances from the nerve to the anterior, posterior, medial, and lateral cortices were 11.6, 12.1, 1.8, and 4.7 mm, respectively. Gender differences were significant for all of these except the medial cortex to nerve distance. On average, the mental foramen exited the body of the mandible immediately below the second premolar and the average surface distances from the foramen to the symphysis, the most cephalad alveolar bone, and the inferior border of the body were 30.9, 14.2, and 19.3 mm, respectively. With regard to the patients presenting for mandibular angle reduction, there were a few statistically significant but small scalar differences from normal controls.

Major hematological diseases associated with cleft lip and palate

OBJECTIVE

Cleft lip and palate is among the most common congenital anomalies. Its association with major blood disorders has rarely been reported. The purpose of this study was to report two patients who had major blood diseases associated with cleft lip and palate.

PATIENTS AND RESULTS

From June 1995 to December 1997, there were 2700 patients with cleft lip, cleft palate, or both who received treatment at Chang Gung Memorial Hospital. Two of them were found to have major hematological disorders. In both cases, the disorder was detected by preoperative blood cell counts and white cell differentiation. Case 1 was a 21-year-old woman patient with repaired right cleft lip. She was admitted for alveolar bone grafting and closure of oronasal fistula. Abnormal presentation of blast cells was found, and subsequent bone marrow study confirmed acute lymphocytic leukemia. Case 2 was a 26-year-old man with left secondary cleft lip nasal deformity scheduled to receive staged reconstructive operations. An elevated platelet count was found and subsequently confirmed to represent essential thrombocytosis. In both cases, reconstructive operations for the cleft-related deformities were performed.

CONCLUSIONS

Association of major hematological disorders and cleft lip, palate, or both is rare and is reported herein.

The effect of hamulus fracture on the outcome of palatoplasty: a preliminary report of a prospective, alternating study

OBJECTIVE

To determine whether, in performing palatoplasty, fracture of the pterygoid hamulus is beneficial, detrimental, or neutral with respect to intraoperative and perioperative complications, hearing outcome, and speech outcome.

DESIGN

Prospective, alternating.

SETTING

Institutional, tertiary cleft palate center, Chang Gung Memorial Hospital, Taipei, Taiwan.

PARTICIPANTS

A total of 173 patients enrolled in the study, of whom 161 had charts available for analysis.

INTERVENTIONS

During the performance of palatoplasty, 85 patients received hamulus fracture and 76 patients did not. All palatoplasties were performed by the same surgeon.

MAIN OUTCOME MEASURES

(1) Surgical outcomes, including patient demographic data, palatoplasty type and duration, blood loss, incidences of oronasal fistulae, temporary mucosal dehiscence, and postoperative bleeding; (2) otolaryngological outcomes, including hearing results as judged by auditory brainstem response testing, myringotomy tube data describing rates of tube extrusion, and culture results from sampled effusions; and (3) preliminary speech outcomes as described by judgments of overall velopharyngeal function from perceptual speech samples.

RESULTS

No statistically significant differences in any of the measured surgical, otolaryngological, or preliminary speech outcomes were found between the groups who did and did not receive hamulus fracture.

CONCLUSIONS

On the basis of these results, we are unable to advocate the performance of hamulus fracture as an operative maneuver during the performance of primary palatoplasty. The historical rationale and theoretical advantage of this maneuver have not been demonstrated here nor have any detrimental effects of the maneuver been measured.

Quantitative measurement on three-dimensional computed tomography: an experimental validation using phantom objects

BACKGROUND

The use of 3-dimensional computed tomography (CT) imaging has been applied to the craniofacial region as well as to many other parts of the human body. Quantitative measurements have frequently been performed on the 3-dimensional images. However, critical validation of the measurement has been insufficient in the literature. This study was designed to evaluate the errors of the 3-dimensional measurements.

METHODS

Four phantom objects, a cube, a sphere, a cylinder, and a life-size adult skull model, were scanned using standard CT acquisition protocol. The data were transferred, reformatted, and displayed on an IBM-compatible personal computer running AnalyzePC 2.5 software. Linear, area, and volume measurements were obtained using one of the two methods. The first was physical measurement of the phantom objects using a caliper for linear measurement and mathematical calculations for area and volume measurements. The second was done by computer measurement on 3-dimensional images using the AnalyzePC 2.5 program. Each measurement was performed twice. The differences were compared between the repeated measurements and between the two methods.

RESULTS

The images were displayed according to standard 3-dimensional CT protocol. The differences between the measurements were insignificant and ranged from 0.00 to 2.57%.

CONCLUSION

This study validated the accuracy of the quantitative measurements on 3-dimensional CT images.

Social support and life adjustment for teenagers with cleft lip and palate in Taiwan

BACKGROUND

The teenage years (13-19 years) are a critical period for psychosocial development. Therefore, social support and life adjustment for teenagers with cleft lip/palate were chosen for investigation.

METHODS

The sample survey included 101 cleft patients randomly selected from the Chang Gung Craniofacial Center, and 101 non-cleft controls selected from local middle and high schools for comparison. Questionnaires were used to evaluate the social support and life adjustment scales. Items of social support were subdivided into social activities, social service, and psychological support. Items of life adjustment were subdivided into social, psychological, and physical adjustments.

RESULTS

The coefficients of alpha reliability were high at 0.9294 for social support, and 0.9389 for life adjustment. The results show that personal factors, family factors, and treatment status do not influence social support or life adjustment in either group; however, gender does. In the control group, non-cleft males had better social support and life adjustment than did females. Such a difference was not observed in the cleft group. Both groups received the same social support. The cleft teenagers have a significantly lower level of life adjustment. The association between the social support and life adjustment is high in both groups.

CONCLUSION

The cleft group has a lower level of life adjustment. There is a positive relationship between social support and life adjustment. More social support is required for the cleft group in order to improve their level of life adjustment.

Temporal expression and T3 induction of thyroid hormone receptors alpha1 and beta1 during early embryonic and larval development in zebrafish, Danio rerio

The effects of thyroid hormones on metabolism and development are mediated by thyroid hormone receptors (TRs). We report the cloning and characterization of a TR beta1 cDNA from zebrafish. Southern blot analysis revealed that there is a single genomic locus for the TR beta gene, while the TR alpha gene potentially has two loci. Multiple TR alpha and TR beta transcripts were detected in adult tissues. Using a semiquantitative RT-PCR assay, zygotic expression of TR alpha1 and TR beta1 were shown to occur before the midblastula transition stage. In transiently transfected HeLa cells, TR alpha1 displayed constitutive transactivation in the absence of ligands, which was slightly enhanced by triiodothyronine (T3). The transactivating activity of TR beta1 was strictly ligand-dependent and repressed in the absence of T3. Finally, the T3 induction of TR alpha1 and TR beta1 mRNAs was demonstrated in zebrafish embryos and larvae. The auto-induction of TR alpha1 and TR beta1 may serve a regulatory role during the embryonic and larval development of zebrafish.

A comparative study of various fixation methods for mandibular fracture

BACKGROUND

Internal rigid fixation for mandibular fractures has been recognized as a reliable method for obtaining osteosynthesis. It may allow for early active physiotherapy and resumption of normal function. However, few studies have compared the various fixation methods.

METHODS

From January 1993 through December 1997, 101 patients with mandibular fractures, who were selected for study, received treatment using various fixation methods at the Craniofacial Center, Chang Gung Memorial Hospital. The fixation methods included plate fixation in 44 patients, lag screw fixation in 30, combined plate and lag screw fixation in 15, and wire fixation in 12. Clinical data assessment was performed by reviewing hospital records. For assessment of the long-term surgical results, the patients were asked to complete a questionnaire including questions which specifically targeted history regarding occlusion, mastication, facial asymmetry, width of mouth opening, and general appearance.

RESULTS

The outcome assessment showed statistically different results among the groups. The wire group required intermaxillary fixation more often and for a longer duration compared to the groups using plates and/or lag screws. The plate, lag screw, and combined plate and lag screw fixation groups had better total outcome scores, in particular for long-term dental occlusion and mastication function.

CONCLUSION

This study shows that for mandible fractures, the more rigid types of fixation methods, i.e., plates and screws or lag screws, can offer better short and long-term outcomes.

Airway obstruction in severe syndromic craniosynostosis

Airway obstruction is frequent in patients with severe syndromic craniosynostosis, and must be treated for successful, complete care. The purpose of this study was to evaluate the incidence and the management of airway obstruction in patients with severe craniosynostosis. All patients with complex syndromic craniosynostosis at Chang Gung Craniofacial Center were evaluated retrospectively. Criteria for inclusion of patients were the presence of adequate follow-up and documentation. A total of 40 patients were included, of whom 13 had Apert's syndrome and 27 had Crouzon's disease. Clinical symptoms and signs related to airway obstruction and its treatment were evaluated carefully, and were verified further by telephone inquiry. The status of the airway was categorized into one of three groups: no obstruction; mild obstruction, for which positioning and medical treatment were needed; and severe obstruction, for which surgical intervention was needed. The results showed that 24 patients (60%) did not have airway obstruction, 11 patients (27.5%) had mild obstruction, and 5 patients (12.5%) had severe obstruction. There was no significant difference in the distribution of airway status between patients with Apert's syndrome and Crouzon's disease. Causes for the 5 patients with severe obstruction were midface hypoplasia, lower airway obstruction, tonsillar and adenoid hypertrophy, and choanal atresia. Tracheostomy was performed to control airway in 3 patients, and 1 patient died. Midface anterior distraction helped to decannulate 1 patient. In conclusion, airway obstruction was observed in 40% of patients with severe craniosynostotic syndromes. Most of them could be managed successfully with conservative or medical treatment, and surgical intervention should be considered on the basis of each patient's individual condition.

Maxillary growth after palatal denudation: an animal experiment

BACKGROUND

Palate surgery at an early age may cause retardation of maxillary growth. The second intention healing of the raw bone surface created on the palate is considered to be the cause of the growth retardation. The animal experiment in this study was designed to evaluate this effect.

METHODS

Four-week-old Sprague-Dawley rats were divided into 3 groups. In the first group, a strip of mucoperiosteum was excised on both sides of the hard palate. A second group of rats received a sham surgery in which bilateral mucoperiosteal flaps were raised and redraped. The third group served as controls with no surgery. Flap elevation with and without excision was performed under an operative microscope to facilitate the delicate manipulation of tissue and to avoid injury to the underlying bone. The animals were killed 11 weeks later and the skulls were prepared for measurements, which included the palatal inter-molar width, maxillary height, and maxillary length.

RESULTS

The results revealed statistically significant decreases in palatal width and maxillary length in the experimental group (excision of mucoperiosteum). No differences were observed in the vertical height of the maxilla.

CONCLUSION

This study confirms that surgically created bone denudation of the palate causes maxillary growth disturbances.

Palatoalveolar outcome at 18 months following simultaneous primary cleft lip repair and posterior palatoplasty

It is frequently reported that early repair of the soft palate induces narrowing of the remaining palatal cleft and thus facilitates later hard palate closure. However, to the best of our knowledge, there have been no comparative studies to test this hypothesis. The purpose of this retrospective study was to evaluate the change of palatoalveolar morphology following primary lip repair and posterior palatoplasty. Dental plaster models of patients with complete unilateral cleft of lip and palate (UCLP) were used to measure the width of the cleft and palatal arch. Twenty-six patients received simple posterior palatoplasty (PP group) simultaneous with primary lip repair, and 20 patients did not (NPP group). The dental models included one preoperative cast at 2 months (T1) and two or three casts at 6 (T2), 12 (T3), and 18 (T4) months before final palate closure. The linear measurements performed were width of alveolar cleft (Ca); width of palatal cleft between the canines (Cc), molars (Cm), and tuberosities (Ct); the palatal arch distance between the canines (Dc); the widest distance between molars (Dm) and the tuberosities (Dt); and the palatal height between the canines (Hc) and tuberosities (Ht). The raw measurements and the calculated cleft-to-arch ratios of Cc/Dc, Cm/Dm, and Ct/Dt were compared between the two groups. The results showed gradual narrowing of the width of cleft from T1 to T4. Narrowing of alveolar cleft width (Ca) from T1 to T2 was dramatic. The palatal arch (Dc, Dm, Dt) showed no change to mild increase in width. The cleft-to-arch ratios decreased with time. The palatal height remained the same or slightly increased over time. There were no significant differences observed between the PP and NPP groups among these measurements except for the Ct and Ct/Dt at T4. In conclusion, after initial lip repair, there was a decrease of the width of cleft in patients with complete UCLP during the 18-month period, and simple posterior palatoplasty did not further narrow the cleft nor influence palatal arch development.

Three-dimensional computed tomographic analysis of the primary nasal deformity in 3-month-old infants with complete unilateral cleft lip and palate

The purpose of this study was to analyze the geometry of the primary cleft lip nasal deformity using three-dimensional computerized tomography in a group of 3-month-old infants with complete unilateral cleft lip and palate before surgical intervention. Coordinates and axes were reconfigured after the three-dimensional image was oriented into neutral position (Frankfurt horizontal, true anteroposterior, and vertical midline). Display and measurement of skin surface and osseous tissues were achieved by adjusting the computed tomographic thresholds. S-N, N-ANS, S-N-O, and S-N-ANS were measured from true lateral views. Biorbital (LO-LO), interorbital (MO-MO), intercanthal (en-en), and nasal (al-al) widths were measured from the anteroposterior view. The bony alveolar cleft width was measured from the inferior view. The study group was divided into two groups on the basis of skeletal alveolar cleft width: six patients with clefts narrower than 10 mm and six patients with clefts wider than 10 mm. Only the S-N-ANS angle differed between the two groups, i.e., it was greater in the group with the wider clefts (p < 0.05). Coordinates of six landmarks at the base of the nose [sellion (se), subnasale (sn), cleft-side and noncleft-side subalare (sbal-cl and sbal-ncl), and the most posterior point on the lateral piriform margins (PPA-CL and PPA-NCL)] were obtained for analysis of the nasal deformity. On average, the subnasale point was anterior to sellion and deviated to the noncleft side; the cleft-side sbal point was more medial, posterior, and inferior than the noncleft-side sbal point; and the PPA point on the cleft-side piriform margin was more lateral, posterior, and inferior than the PPA point on the noncleft side. These discrepancies were not universally observed. However, in all patients, four findings were observed without exception (p < 0.01): (1) subnasale (sn) was deviated to the noncleft side (mean distance from midline, 5.0 mm; range, 2 to 9.5 mm), (2) the cleft-side alar base (sbal-cl) was more posterior than the noncleft-side alar base (sbal-ncl) (mean difference, 3.6 mm; range, 1 to 5.5 mm), (3) the noncleft-side alar base (sbal-ncl) was further from the midline than the cleft-side alar base (sbal-cl) (mean difference in lateral distances of sbal-ncl and sbal-cl from the midline, 2.8 mm; range, 0.5 to 7 mm), and (4) the cleft-side piriform margin (PPA-CL) was more posterior than the noncleft side piriform margin (PPA-NCL) (mean difference, 2.1 mm; range, 0.5 to 4 mm). In conclusion, the nasal deformity in unilateral cleft lip and palate that has not been operated on is characterized by these four features and increased S-N-ANS angle with increased alveolar cleft width.

Bilateral coronoid process hyperplasia with limitation on mouth opening: case report

Coronoid process hyperplasia with limitation of mouth opening is rare. The pathology is often ignored, but it can be easily detected using dental panoramic view of x-ray films. Definition of the coronoid process hyperplasia can be made by measuring the height of coronoid process and the ratio of coronoid/condyle height on lateral cephalometric x-ray film. Etiology of the coronoid process hyperplasia can be congenital or acquired. Differentiation of the diagnosis may be difficult. The congenital type occurs at early age with clinical manifestations. Proposed hypotheses for the formation of coronoid process hyperplasia include increased activity within the temporalis muscle from conditions such as functional stress, compression, and tension. For patients with coronoid process hyperplasia and restriction on mouth opening, conservative treatment should first be attempted. Surgical treatment is considered if conservative treatment fails. Coronoidectomy with early mobilization and aggressive physiotherapy corrects the problem. We present a patient with coronoid process hyperplasia with limitation of mouth opening who was successfully treated.

Cleft of the lip and palate in twins

BACKGROUND

Cleft lip and palate is one of the most common congenital anomalies in Taiwan. Its etiology remains unknown for the majority of the patients. The study of twins is a classic method for evaluating the relative roles of genetic and environmental factors in the formation of the anomaly.

METHODS

In this study, 37 pairs of twins and one set of triplets with cleft lip and palate were evaluated. Clinical data were collected for zygosity determination and analysis of etiologic factors. The concordance rate and heritability index were assessed.

RESULTS

The results showed that the concordance rate was 26% for all twins and 57% among the monozygotic pairs, which is higher than those rates for the Caucasian population. The heritability index was 53%, higher than the other reports as well. The influence of the environment could not be ruled out.

CONCLUSION

The results confirm a strong genetic role in the etiology of clefts in our patients. Environmental factors were acting as well. The findings in this study support the multifactorial threshold model in the development of cleft lip and palate.

The Le Fort I-palatal split approach for skull base tumors: efficacy, complications, and outcome

The Le Fort I, split-palate approach provides intraoral surgical access to a region of the midline skull base ranging from the upper clivus to the second cervical vertebra. Although this approach provides perhaps the largest exposure of all the intraoral techniques, there is little concerning it in the literature. Furthermore, there are no detailed descriptions of case histories, complications, and outcome. The purpose of this study was to evaluate this procedure's effectiveness and identify associated complications as well as outcome. Seven cases of patients who underwent eight skull base surgeries using the Le Fort I, split-palate approach were evaluated retrospectively. Particular attention was paid to postoperative occlusion, speech, mouth opening, infection, tumor recurrence, postoperative recovery period, and viability of maxillary bone and teeth. Follow-up ranged from 4 months to 7 years with a mean of 3.9 years. Pathologic diagnoses included three chordomas (two recurrent), one recurrent meningioma, one liposarcoma, one chondrosarcoma, and one inflammatory mass. One patient with chordoma underwent a second operation using the same approach. No deaths or major neurologic problems related to the procedure occurred. One patient who had known local metastases at the time of operation died several months after surgery. All other patients are still living. Duration of hospital stay ranged from 5 to 53 days with a mean of 25.4 days. Postoperative complications included one case of meningitis with an associated cerebrospinal fluid leak, three cases of malocclusion, one case of velopharyngeal insufficiency, and one extracranial soft-tissue infection. The case of meningitis was successfully treated by antibiotics. The malocclusions were corrected by conservative treatment. No problems with mouth opening or bone or tooth viability occurred. Tumor recurred in both cases in which malignancy was involved, whereas only one recurrence was noted among the benign cases. It is concluded that the Le Fort I-palatal split technique is a relatively safe and effective means for approaching midline skull base tumors. Several modifications to the surgical protocol and surgical technique are detailed herein.

Infantile myofibromatosis: a solitary lesion involving the upper lip

Infantile myofibromatosis is a rare disease characterized by myofibroblastic proliferation, and typically occurs in early infancy. There is a wide spectrum of clinical presentation, which may involve various kinds of tissues in the body. Skin and subcutaneous lesions were the types of tissue most often seen. Although a multicentric form may behave aggressively, a solitary form of the tumor is benign with the possibility of spontaneous regression. Conservative management is justified after proper pathological diagnosis if the tumor involves an aesthetically important area. A case of solitary infantile myofibromatosis involving the upper lip is presented. Partial excision for biopsy was performed and long-term observation was undertaken. The tumor disappeared 3 years postoperatively.

Relationship between bone and muscles of mastication in hemifacial microsomia

The relationship between the bone and muscles of mastication in hemifacial microsomia was studied using three-dimensional volumetric computed tomography scans and image processing techniques. High resolution head computed tomography scans were obtained from 31 patients with unilateral hemifacial microsomia and eight normal patients. Using three-dimensional volume renderings of bone, mandibular deformities in patients with hemifacial microsomia were classified using the Pruzansky system. For each patient, specific craniofacial bones (temporal bone, maxilla mandible) and the muscles of mastication (masseter, temporalis and lateral and medial pterygoid) were segmented bilaterally from the image volume for independent display and volume measurement. Volumes were expressed as the ratio of the affected: unaffected sides. For the masseter and temporalis, the relationship between muscular hypoplasia and osseous hypoplasia in its origin and insertion was studied by plotting affected:unaffected bone volume as a function of affected:unaffected muscle volume for each muscle, bone of origin, bone of insertion triplet. The volumes of the pterygoid muscles were compared with hemimandibular volumes. The precision of object segmentations was examined by repetitive definition tasks, whereas the accuracy of volume measurement was tested by scanning custom-made phantom objects and comparing digital to physical object volume measurements. Volume measurements performed using these techniques were both accurate and precise. In hemifacial microsomia, the extent of hypoplasia of specific muscles of mastication predicted the extent of dysplasia in their osseous origin and insertion. However, the reverse was not true. The extent of hypoplasia of the facial bones did not necessarily predict the extent of hypoplasia in the attached muscles of mastication. Pruzansky grade of the mandible described the degree of mandibular hypoplasia on the affected side, but was inconsistent in its prediction of volume decrease of the other facial bones.

Mandibular dysmorphology in unicoronal synostosis and plagiocephaly without synostosis

Patients with unicoronal synostosis (UCS) or plagiocephaly without synostosis (PWS) have distinctive skull dysmorphologies. Associated mandibular dymorphologies have been suspected but not quantified. This study was performed to test the hypothesis that discrete mandibular dysmorphology exists in both UCS and PWS. All patients at a tertiary referral center at a medical school-affiliated children's hospital with confirmed diagnosis of UCS or PWS with adequate pretreatment CT data were included in the study population, which population was comprised of 20 UCS, 23 PWS, and 8 normal infants. Each patient had a head CT scan using 2-mm slices. 3-D images were created using Analyze, a biomedical imaging program. The mandibles were isolated, and the coordinates of 8 landmarks were sampled from each mandible by a single investigator: a single volume value was measured, and 9 linear distances and 4 angles were calculated. Corresponding measurements from each hemimandible were expressed as ratios of ipsilateral/contralateral side. In UCS, the affected side was defined as the side ipsilateral to the synostosis; In PWS, the affected side was defined as the side ipsilateral to the occipital flattening. The results from both groups were t tested for statistical significance. For UCS, statistically significant (p < .001) findings included: ipsilateral hemimandibular volume 5% smaller than contralateral; affected hemimandibular body length 1.9% shorter; affected gonial angle 2.6% more acute; affected coronoid process tilted anteriorly 2.5%; and distances from condylion and tip of the coronoid process to the chin landmarks 4% shorter on the affected side. For PWS, significant findings included: affected hemimandibular volume 3.8% larger; ramal height 3.5% shorter; mandibular body length 3% longer; and coronoid process tilted anteriorly by 2.3% on the affected side. In the UCS/PWS comparison, findings included: affected hemimandibular volume in UCS 8.7% less; affected gonial angle in UCS 3% more acute; affected mandibular corpus length in UCS 5% shorter; distances from the condylion and the tip of the coronoid process to the chin landmarks 4% shorter on the affected side in UCS. The hypothesized presence of diagnosis specific mandibular dysmorphology in UCS and PWS is confirmed. This analysis forms the baseline for study of the effects of unperturbed growth or therapeutic interventions upon the dentoskeletal dysmorphology of these anomalies.

Stability of fronto-orbital advancement in nonsyndromic bilateral coronal synostosis: a quantitative three-dimensional computed tomographic study

Fronto-orbital dysmorphology in nonsyndromic bilateral coronal synostosis includes frontal flattening, supraorbital recession, and ocular globe protrusion. Surgical advancement of the supraorbital region ("bandeau") is performed to correct these deformities. A retrospective analysis of 10 consecutive patients with nonsyndromic bilateral coronal synostosis was performed to assess the effect of two types of bandeau fixation at the nasion. The advanced bandeau was fixed medially at the nasion with a calvarial bone graft and polyglycolic acid sutures (bone graft/suture group, five patients) or with a microplate (plate group, five patients) and bilaterally at pterion with calvarial bone grafts and polyglycolic acid sutures (all patients). The cranio-orbital dysmorphology and the surgical results were studied using pre-, peri-, and post-operative three-dimensional computed tomographic (CT) data. Reformation, manipulation, editing, and quantitative measurements of the CT data were performed on a computer workstation and Analyze imaging program. Four measurements performed to evaluate the fronto-orbital morphology: the length:width ratio of anterior cranial fossa, ventral globe index, cornea position, and supraorbital rim lag. The ventral globe index assessed the degree of eyeball protrusion out of the orbit cavity. Measurements of the cornea position and supraorbital rim lag were performed on the longitudinal orbit projections of the CT data. Six normal skull CT scans were available for same measurement and comparison. Measurements of the preoperative fronto-orbital dysmorphology in bilateral coronal synostosis were significantly different from those of normal subjects. One year after the surgery, the length:width ratio of the anterior cranial fossa was normalized in both groups. The ventral globe index was improved but not normalized in both groups, whereas the cornea position and supraorbital rim lag were improved in the bone graft/suture group but were normalized in the plate group. Based on the quantitative data, the surgical outcomes in the plate group were significantly better than those in the bone graft/suture group. Major relapse of surgical advancement in the bone graft/suture group seemed to occur in perioperative period. In summary, at 1 year postoperatively, the bandeau advancement improved but did not entirely normalize the fronto-orbital dysmorphology of nonsyndromic bilateral coronal synostosis in either group. We conclude that plate rigid fixation at the nasion provides superior stability for bandeau advancement compared with bone graft/suture fixation.

Orbital dysmorphology in unilateral coronal synostosis

Unilateral coronal synostosis (UCS) produces overt craniofacial dysmorphology. UCS surgery in infancy aims to release the osseous restriction and normalize the fronto-orbital deformity. The quantitative effect of this surgery on the orbit and its contents is unknown. This study was conducted to quantify the preoperative orbital dysmorphology and its surgical outcome in patients with unilateral coronal synostosis. Twenty-eight UCS patients had preoperative three-dimensional computerized tomographic (CT) scans (at mean age 4.0 months), cranio-orbital reconstructive surgery (at 4.7 months), and postoperative scans (at 18.1 months). The CT data were analyzed using a computer workstation and AnalyzeTM biomedical imaging software. Four measurements were performed on both ipsilateral (same side as synostosis) and contralateral (opposite to synostosis) orbits of each scan: orbital index (OI, 100 x height/width of orbit), orbital cavity volume (OV), ocular globe volume (GV), and ventral globe Index (VGI, 100 x globe volume ventral to the anterior surface of orbital cavity/GV). The data were analyzed for statistical significance using Student's ttest. Preoperatively, the OI was significantly greater on the ipsilateral than on the contralateral side (113.7 vs. 87.3). There was a significant improvement on both sides of the orbit postoperatively, with ipsilateral 99.1 and contralateral 92.1. However, the difference between both sides remained significant. The OV was smaller in the ipsilateral orbits both pre- and postoperatively, with ipse/contralateral ratios of 95.8 and 95.2, respectively. Importantly, the GV was consistently smaller in the ipsilateral orbits preoperatively, with an ipse/contralateral ratio of 93.3. The ratio increased to 97.1 postoperatively, a statistically significant change. In the ipsilateral orbits, the preoperative VGI was significantly greater. The VGI improved postoperatively. These data indicate that UCS affects the development of the osseous orbit as well as its soft-tissue contents. After cranio-orbital surgery, there is diminution of asymmetry of both the bony orbit and its soft-tissue contents. Partial normalization of orbital dysmorphology occurred during the first postoperative year. UCS surgery in infancy does not prevent growth of orbital hard or soft tissues, and it seems to permit normalization of previously impaired growth.

Plagiocephaly: differential diagnosis based on endocranial morphology

Plagiocephaly is a descriptive term that connotes an asymmetrically oblique or twisted head. Such cranial dysmorphology has a number of etiologies, the most common of which are unicoronal synostosis, unilambdoid synostosis, and plagiocephaly without synostosis. Use of the term plagiocephaly in the literature is often ambiguous in that at times it is used inclusively for all etiologies while at other times it is used exclusively as a synonym for unicoronal synostosis. Although differentiation by physical examination among unicoronal synostosis, unilambdoid synostosis, and plagiocephaly without synostosis usually is possible for an experienced observer, inexperienced observers often have difficulty making an anatomically accurate diagnosis even with the assistance of conventional skull radiographs. High-resolution CT scans, including three-dimensional osseous surface re-formations, have become a standard element in the evaluation of craniofacial anomalies in many centers. We hypothesized that the three major etiologies of plagiocephaly could be unambiguously differentiated by means of endocranial three-dimensional CT osseous surface re-formations. Archival pretreatment CT data on 15 unicoronal synostosis, 4 unilambdoid synostosis, and 15 plagiocephaly without synostosis patients were reviewed to define, qualitatively and quantitatively, the characteristics of the endocranial base morphologies for each group; in addition to visual dysmorphology specific to each group, there was a statistically significant difference in the angle of deviation from the midlines of the anterior and posterior cranial fossae among unicoronal synostosis, unilambdoid synostosis, and plagiocephaly without synostosis. Four radiologists experienced in reading images of craniofacial anomalies were oriented to the group characteristics and then instructed to perform differential diagnosis for each of the 34 patients using only the endocranial three-dimensional CT images. The raters were blind to all other clinical and diagnostic information. The raters correctly diagnosed unicoronal synostosis. Errors were made in differentiation of unilambdoid synostosis and plagiocephaly without synostosis. These errors resulted from the raters' reliance on image inspection rather than quantitation of anteroposterior fossae midline angulation. Such quantitation unambiguously differentiated between unilambdoid synostosis and plagiocephaly without synostosis in the "error" cases. The endocranial base dysmorphology of patients with plagiocephaly is etiology-specific for unicoronal synostosis, unilambdoid synostosis, and plagiocephaly without synostosis. Three-dimensional CT endocranial base images can assist differential diagnosis of plagiocephaly.

Craniofacial computer-assisted surgical planning and simulation

Computer-assisted planning and simulation of craniofacial surgery has progressed from development, through validation, and into clinical use. CT scans are transferred from the radiology department to a graphics workstation in the surgeon's office or laboratory, where data postprocessing and visualization for anatomic evaluation and surgical simulation are performed. Quantitative and qualitative comparative analyses between the plan/simulation and the actual postoperative result provide the feedback that validates or refutes the preoperative assessment and simulated intervention. The optimum surgical solution can be chosen from many possibilities. Interactive computer-assisted surgical simulation is also useful for morbidity-free training of inexperienced surgeons.

Cleft lip and hemangioma: a patient with Wolf-Hirschhorn syndrome

A patient with Wolf-Hirschhorn syndrome had multiple congenital anomalies and a right cleft lip. Hemangioma involved the full thickness of the upper medial lip segment at the age of 2 months, which caused lip repair to be very difficult. The first attempt at adhesion cheiloplasty resulted in complete separation. The tumor did not respond to steroid treatment. A subsequent trial of lip repair with the assistance of a tension-relieving suture tied to the nasal septum was successful. This type of tension suture is helpful to prevent dehiscence when security of lip closure is questionable or cannot be achieved.

Proximal deletion of the long arm of chromosome 1: [del(1)(q23-q25)]

A patient with bilateral complete cleft of the lip and palate (CLP) had a proximal deletion of the long arm of chromosome 1 (1q). This rare chromosomal abnormality was characterized by pre- and postnatal growth retardation, psychomotor retardation, and specific craniofacial and other systemic anomalies. There is a high incidence of CLP in proximal 1q deletion syndrome, especially bilateral CLP. Twelve other cases reported in the literature having this deletion and associated anomalies were reviewed.

Use of split anterior tibial muscle flap in treating avulsion injury of leg associated with tibia exposure

Avulsion injury of the leg may result in exposure of the anterior surface of the tibia in addition to skin loss. This exposed bone should be covered by a soft tissue flap to facilitate healing and provide durability. The split anterior tibial muscle flap is ideal in this situation because of its adjacent location, reliability, and simplicity. A cadaveric study demonstrated rich intramuscle vascular anastomoses between the segmental branches from the anterior tibial artery that provide safety in partial transfer. The technique of split anterior tibial muscle flap was applied successfully in 4 patients with leg avulsion injury associated with tibial bone exposure. The cosmetic result was good and the function of the muscle was preserved.

Median facial dysplasia in unilateral and bilateral cleft lip and palate: a subgroup of median cerebrofacial malformations

The median facial dysplasia group of patients is a unique, distinct, definable group characterized by mid-line facial deficiencies in the presence of a unilateral or bilateral cleft lip with or without cleft palate and without clinically detectable anomalies of the brain. This group of patients comprised 2 percent of new cleft lip and palate patients. The midline facial deficiencies in median facial dysplasia are characterized by a poorly defined Cupid's bow, absence of the labial frenulum and anterior nasal spine, deficient columella, and poorly developed septal cartilage and premaxilla. One of the central incisors may be absent or rudimentary. There are no definable gross abnormalities of the brain. The results of intelligence tests of median facial dysplasia patients have a normal distribution and are not significantly different from those of a noncleft normal population. Unoperated and operated median facial dysplasia patients all have typical midfacial growth disturbances below the norm for their ages. The classification of median facial dysplasia patients as well as other median cerebrofacial anomalies, the embryologic basis of these deformities, and the clinical results of their treatment are helpful in understanding some of the problems related to the treatment of the cleft lip and palate patient. Median facial dysplasia patients demonstrate an inherent potential for poor midfacial growth. Deficiencies of soft tissue such as a lack of the Cupid's bow make it difficult to reconstruct the lip and nose satisfactorily.

Facial midline and symmetry: modified face bow

A facial "cone" can be drawn inside the head. The apex of the cone is the midpoint of the line that connects both ear canals, point C, and the face is the base. A modified face bow is designed with holes through which a Steinmann pin is passed, meeting at the apex of the facial cone. After the ear bolts are symmetrically fixed, the Steinmann pin through the central hole follows the midline of the face as the bow rotates from the forehead to the chin. The right and left facial bony protrusions can be evaluated by two Steinmann pins projecting through the corresponding holes on the face bow. This device is utilized to determine the facial midline and facial symmetry during surgery. It also can be used as a tool for anthropologic studies.

A simple and effective method of compression dressing for skin grafts

Skin grafting is one of the most common procedures in plastic and reconstructive surgery. Various methods of fixation and dressing, to achieve good approximation and immobilization of skin grafts and, thus, to bring about better graft survival, are described. A simple method utilizing readily available latex and staples provides good fixation and compression. This technique has been applied in 50 patients requiring skin grafts. The morbidity and complications were minimal, and the grafts have taken satisfactorily. Pressure study with an animal model has revealed adequate compression.

Free flap transfer in burn reconstruction

Wound healing in burn patients with exposure of vital tissues has been greatly facilitated by the use of free flap transfers for reconstruction with good functional as well as aesthetic results. Preoperative angiography is not an indispensable way to localize recipient vessels. Knowledge of the changes that occur in vessels at the zone of injury is crucial in the selection and preparation for microsurgical anastomosis. One team approach is advocated because the plan for the procedure may be changed when no appropriate recipient vessel is located during the dissection. We present our study of ten cases followed up in the last six years. Nine cases were successful, and severe wound infection resulted in one flap failure. Proper recipient vessel selection and adequate wound debridement are important factors for successful free flap transfer in burn reconstruction.