Martin H. S. Huang

The differential diagnosis of posterior plagiocephaly : true lambdoid synostosis versus positional molding

&NA; The diagnosis and treatment of posterior plagiocephaly is one of the most controversial aspects of craniofacial surgery. The features of true lamibdoid synostosis versus those of deformational plagiocephaly secondary to positional molding are inadequately described in the literature and poorly understood. This has resulted in many infants in several craniofacial centers across the United States undergoing major intracranial procedures for nonsynostotic plagiocephaly. The purpose of this study was to describe the detailed clinical, imaging, and operative features of true lamhdoid svnostosis and contrast them with the features of positional plagiocephaly. During a 4‐year period from 1991 to 1994, 102 patients with posterior plagiocephaly were assessed in a large multidisciplinary craniofacial program. During the same period, 130 patients with craniosynostosis received surgical treatment. All patients were examined by a pediatric dysmorphologist, craniofacial surgeon, and pediatric neurosurgeon. Diagnostic imaging was performed where indicated. Patients diagnosed with lambdoid synostosis and severe and progressive positional molding underwent surgical correction using standard craniofacial techniques. Only 4 patients manifested the clinical, imaging, and operative features of unilambdoid synostosis, giving an incidence among all cases of craniosynostosis of 3.1 percent. Only 3 among the 98 patients with positional molding required surgical intervention. All the patients with unilambdoid synostosis had a thick ridge over the fused suture, identical to that found in other forms of craniosynostosis, with compensatory contralateral parietal and frontal bossing and an ipsilateral occipitomastoid bulge. The skull base had an ipsilateral inferior tilt, with a corresponding inferior and posterior displacement of the ipsilateral ear. These characteristics were completely opposite to the findings in the 98 patients who had positional molding with open lambdoid sutures and prove conclusively that true unilambdoid synostosis exists as a specific but rare entity. Awareness of the features of unilambdoid synostosis will allow more accurate diagnosis and appropriate treatment of posterior plagiocephaly in general and in particular will avoid unnecessary surgical intervention in patients with positional molding. (Plast. Reconstr. Surg. 98: 765, 1996.)

Anatomic basis of cleft palate and velopharyngeal surgery: implications from a fresh cadaveric study.

&NA; The purpose of this investigation was to apply the findings of an anatomic study of the levator veli palatini, palatopharyngeus, and superior constrictor muscles in 18 fresh cadaveric specimens of normal adults to analyze current controversies in velopharyngeal function and cleft palate surgery. The levator veli palatini was observed to form a muscular sling, suspending the velum from the cranial base. Its fibers occupied the middle 50 percent of the velum, lying in transverse orientation and without significant overlap across the midline. It is well placed to function as the prime mover in the velar component of velopharyngeal closure. The velar component of the palatopharyngeus consisted of two heads clasping the levator and inserting into the latter just short of the midline. Its pharyngeal component inserted into the superior constrictor in the lateral and posterior pharyngeal walls. Together, these two muscles formed a sphincter around the velopharyngeal port, suggesting that both muscles are involved in the pharyngeal component of velopharyngeal closure. Based on the premise that the goal of palatoplasty is to restore normal anatomy, the intravelar veloplasty has a sound basis, and theoretically improves both velar and pharyngeal wall function because it corrects the dysmorphology of both the levator and palatopharyngeus. Although the Furlow palatoplasty also reorients these velar muscles correctly in the transverse position, the resulting overlap of the levator and palatopharyngeus across the midline is morphologically abnormal. In addition, the use of large Z‐plasty flaps in wide clefts may cause excessive lateral tension, increasing the risk of fistula formation and causing an impairment of velar stretch capacity. The raising of a vertical pharyngeal flap divides the fibers of the superior constrictor and has the potential to impair pharyngeal wall function. The sphincter pharyngoplasty interferes less with pharyngeal wall anatomy. The potential for an obstructive outcome seems to be related to the use of wide, long flaps and a tight, overlapping type of flap inset. In addition, the level of flap inset is important: an inset at the level of the uvula has the greatest risk of causing obstruction, whereas a higher inset at the level of attempted velopharyngeal closure seems to provide the best opportunity for achieving velopharyngeal competence while avoiding hyponasality and obstruction.

A fresh cadaveric study of the paratubal muscles: implications for eustachian tube function in cleft palate.

&NA; The aims of this anatomic investigation were to examine the levator veli palatini, tensor veli palatini, and salpingopharyngeus muscles in relation to normal eustachian tube function and to analyze the clinical implications of these data for tubal physiology in cleft palate individuals. Detailed dissections under 3.2x loupe magnification were conducted on the paratubal muscles of 15 fresh human adult cadaveric head specimens, paying particular attention to their cranial base anatomy. Each half of the cadaveric heads was examined separately, giving a sample size of 30. The cranial base origin of the levator veli palatini was the junction of the cartilaginous and bony parts of the eustachian tube. Contrary to statements in the existing literature, it had no origin from the quadrate area of the petrous temporal bone. In its path toward the velum, it was related inferiorly and lay almost parallel to the tube. The tensor veli palatini originated from the scaphoid fossa of the sphenoid bone and the tube. In contrast to previous descriptions, it was found to consist of a single sheet of muscle with no bilaminar structure. Its axis was oblique to that of the tube. The salpingopharyngeus was a slender muscle attached to the posteroinferior aspect of the pharyngeal end of the tube. It inserted into the palatopharyngeus inferiorly. These morphologic characteristics and anatomic relationships suggest that (1) the levator veli palatini opens the eustachian tube by isotonic contraction that results in displacement of the medial tubal cartilage and the tubal membrane, (2) the tensor veli palatini opens the the tube directly by traction on the lateral tubal membrane and indirectly by rotation of the medial tubal cartilage by means of traction on the lateral tubal cartilage, (3) because of its consistently small size, the salpingopharyngeus is probably functionally the least important of the paratubal muscles, (4) the levator veli palatini is unable to cause tubal dilatation in cleft palate because it can only contract isometrically, and (5) tensor veli palatini function is probably unaffected by clefting. However, its mechanism of action may be disrupted iatrogenically by complete hamular fracture or division of its tendon. (Plast. Reconstr. Surg. 100: 833, 1997.)

The Differential Diagnosis of Abnormal Head Shapes: Separating Craniosynostosis from Positional Deformities and Normal Variants

The correct differential diagnosis of an abnormal head shape in an infant or a child is vital to the management of this common condition. Establishing the presence of craniosynostosis, which warrants surgical correction, versus non-synostotic causes of head deformity, which do not, is not always straightforward. This paper deals with three groups of abnormal head shape that may cause diagnostic confusion: the spectrum of metopic synostosis; the dolichocephaly of prematurity versus sagittal synostosis; and the differential diagnosis of plagiocephaly. Special emphasis has been placed on the problem of posterior plagiocephaly, in the light of recent evidence demonstrating that lambdoid synostosis has been overdiagnosed. Metopic synostosis presents as a wide spectrum of severity. Although only severe forms of the disorder are corrected surgically, all cases should be monitored for evidence of developmental problems. The dolichocephalic head shape of preterm infants is non-synostotic in origin and is managed nonsurgically. The scaphocephalic head shape resulting from sagittal synostosis requires surgical intervention for correction. Posterior plagiocephaly may be due to unilambdoid synostosis or positional molding, which have very different clinical and imaging features. True lambdoid synostosis is rare. Most cases of posterior plagiocephaly are due to positional molding, which can usually be managed nonsurgically. Regardless of the suture(s) involved, all children with confirmed craniosynostosis should be monitored for increased intracranial pressure and developmental problems.

Anatomic basis of safe percutaneous subclavian venous catheterization.

BACKGROUND The technique of percutaneous catheterization of the subclavian vein by the infraclavicular approach is dependent on the location of the subclavian vein in relation to the clavicle. The purpose of this study was to analyze the anatomic relationship between these two structures and how it is influenced by changes in shoulder positioning. METHODS Dissections of the infraclavicular region were performed in seven fresh cadavers and linear measurements made to determine the extent of overlap between the vein and the clavicle in different shoulder positions. RESULTS When the shoulder was in neutral position, the subclavian vein was overlapped by the medial third or more of the clavicle and this segment of bone was able to serve as a landmark for the vein. However, shoulder elevation displaced the clavicle cephalad and reduced the degree of overlap. Mild shoulder retraction increased the area of contact between the vein and the undersurface of the clavicle, whereas protraction lifted the clavicle off the vein. CONCLUSION Infraclavicular subclavian venipuncture should be performed with shoulders in a neutral position and also in slight retraction. An appreciation of the anatomic relationship between the clavicle and the subclavian vein is the key to successful execution of this technique.

Structure of the Musculus Uvulae: Functional and Surgical Implications of an Anatomic Study

OBJECTIVE The role of the musculus uvulae in velopharyngeal function, its morphologic status in cleft palate, and its fate in palatoplasty procedures are subjects of controversy. The aims of this investigation were to re-examine this velar muscle to clarify its anatomic characteristics, to analyze its role in speech physiology, and to study the surgical implications of this information for cleft palate repair. METHODS Its attachments, morphology, and relations were examined in 18 fresh human adult cadavers by detailed dissection under 3.2x magnification and light microscopy. RESULTS The musculus uvulae was observed to be a paired midline muscle extending between the tensor aponeurosis anteriorly and the base of the uvula posteriorly along the nasal aspect of the velum. It had no attachments to the hard palate. CONCLUSIONS These findings suggest that its action is to increase midline bulk on the nasal aspect of the velum, thus contributing to the levator eminence. It may also have an extensor effect on the nasal aspect of the velum, displacing it toward the posterior pharyngeal wall. Both of these actions would serve to maximize midline velopharyngeal contact. One clinical application of this anatomic information is that the muscle should be preserved in the dissection performed during intravelar veloplasty. Furthermore, it should be recognized that the musculus uvulae is invariably divided and reoriented incorrectly in the Furlow double opposing Z-plasty.

Endoscopic pediatric plastic surgery.

Although the advent of endoscopic technology is expanding the fields of reconstructive and aesthetic surgery in adults, there have been to date no reports of its use in the pediatric population. Because of its minimally invasive nature, yet wide range of exposure, endoscopic techniques have much appeal in this age group. Herein we present our initial experience with endoscopic pediatric plastic surgery. From February 1995 to December 1995, 41 patients were treated utilizing 5-mm and 10-mm endoscopes at Scottish Rite Childrens Medical Center, Atlanta, GA. There were 19 males and 22 females. The mean age at surgery was 5.6 years (range, 7 months-15 years). The most common types of procedures performed were insertion of tissue expanders (N=19), excision of facial dermoids (N=7), torticollis release (N=5), and excision of vascular lesions (N=4). The remaining 6 patients underwent a variety of reconstructive procedures. The complication rate in the tissue expander group was 3 out of 39 expanders inserted (9.5%), and consisted of infection (N=2) and rupture (N=1). In the dermoid group, complications consisted of wound infection requiring reoperation (N=1), and transient frontal paresis (N=1). One patient in the hemangioma group had an incomplete resection necessitating open excision. The remaining patients all had satisfactory outcomes with no complications. The majority of the procedures were done on an outpatient basis. These results suggest that endoscopic techniques are eminently applicable in the pediatric population, providing the benefits of small and remote incisional wounds with complication rates that are comparable to those of conventional surgical treatment. Huang MHS, Burstein FD, Cohen SR, Simms Ca. Endoscopic Pediatric Plastic surgery. Ann Plast Surg 1997;38;1-8

Clinical implications of the velopharyngeal blood supply: a fresh cadaveric study.

&NA; The aim of this investigation was to examine the blood supply of the normal velopharyngeal musculature and its clinical implications. Detailed dissections were performed on each side of five fresh human adult cadaveric head and neck specimens (n = 10) following carotid artery injection with liquid neoprene latex stained with green pigment. The vascular network of the soft palate was situated within its glandular layer. The velopharyngeal muscles were supplied by the following four branches of the external carotid artery: (1) ascending palatine branch of the facial artery, which supplied the palatoglossus, palatopharyngeus, musculus uvulae, and the intravelar part of the levator veli palatini; (2) ascending pharyngeal artery, which supplied the superior constrictor; (3) the previously undescribed recurrent pharyngeal artery, which supplied the extravelar part of the levator veli palatini; and (4) maxillary artery, which supplied the tensor veli palatini. All muscles except the musculus uvulae had at least a dual blood supply. Analysis of this vascular anatomy suggests that (1) the overall generous blood supply of the velum allows it to tolerate the dissection performed during intravelar veloplasty and the Furlow double opposing Zplasty; (2) dissection around the hamulus, along the medial pterygoid plate, and in the space of Ernst should be performed carefully to avoid damage to the ascending palatine artery, ascending pharyngeal, and recurrent pharyngeal arteries; (3) vertical pharyngeal flaps are random pattern in nature; and (4) the posterior tonsilar pillar flaps of the sphincter pharyngoplasty are adequately supplied by the hamular branch of the ascending palatine artery. (Plast. Reconstr. Surg. 102: 655, 1998.)

Applications of endoscopic surgery in pediatric patients

&NA; Although the advent of endoscopic technology is expanding the fields of reconstructive and aesthetic surgery in adults, there have been few reports of the use of this technology in the pediatric population. Because of their minimally invasive nature, yet wide range of exposure, endoscopic techniques have much appeal for this age group. Here we present our experience with endoscopic pediatric plastic surgery. From February of 1995 to August of 1997, 104 patients underwent 139 procedures utilizing 5‐ and 10‐mm endoscopes. There were 58 male and 46 female patients. The mean age at surgery was 5.6 years (range, 3 weeks to 19 years). The most common type of procedures performed were insertion of tissue expanders (n = 34), excision of benign head and neck masses (n = 27), torticollis release (n = 20), excision of vascular lesions (n = 13), and miscellaneous procedures, (n = 10). There were 26 complications in 139 procedures (19 percent). Seventeen (65 percent) were in the tissue expander group. The rest were scattered among the groups with other diagnoses. Although there did not appear to be a specific type of complication associated with endoscopy, 77 percent occurred in the first 2 months of our study. This suggests a relatively steep technical learning curve. These results demonstrate that endoscopic techniques are eminently applicable in the pediatric population, providing the benefits of small and remote incisional wounds, with complication rates that are comparable with those of conventional open surgical treatment. (Plast. Reconstr. Surg. 102: 1446, 1998.)

Severe gastrointestinal bleeding resulting in total gastrectomy in a patient with major burns—a case report

Gastrointestinal hemorrhage is a known but rare complication of major burns. This case report describes the management of this potentially life threatening problem in a young adult with 45% body surface area burns who developed massive gastrointestinal-tract bleeding. The patient required a total gastrectomy that was complicated by a burst abdomen. Despite undergoing a series of major insults. the patient survived and was eventually discharged from hospital with an acceptable level of morbidity. The problems faced by the burn centre team and the issues involved in the decision making process are discussed in the management of this unusually devastating complication.