Anterior Cranial Vault Research Articles

Contemporary Management of Frontal Sinus Fractures

This course is intended for surgeons involved in the management of craniomaxillofacial injuries. Epidemiology, anatomy, physiology, and classification of anterior cranial vault fractures involving the frontal sinus will be presented. Contemporary techniques for repair of frontal sinus injuries will be reviewed. A treatment algorithm with illustrative cases will be presented. ●Epidemiology ●Embryology ●Anatomy ●Physiology

Contemporary management of frontal sinus fractures

This course is intended for surgeons involved in the management of craniomaxillofacial injuries. Epidemiology, anatomy, physiology and classification of anterior cranial vault fractures involving the frontal sinus will be presented. Contemporary techniques for repair of frontal sinus injuries will be reviewed. A treatment algorithm with illustrative cases will be presented. •Epidemiology•Embryology•Anatomy•PhysiologySinus MembraneFronto-Nasal Drainage Apparatus•EvaluationClinicalDiagnostic imaging•Classification of Frontal Sinus Fractures•Management Algorithm•Surgical Approaches•Intra-operative Assessment of Fronto-Nasal Drainage Function MethodsTreatment Decisions; Preservation, Repair or Obliteration•Fracture Repair and Fixation Considerations•Post-operative Management and Follow-up•Complications

Contemporary management of frontal sinus fractures

This course is intended for surgeons involved in the management of craniomaxillofacial injuries. Epidemiology, anatomy, physiology, and classification of anterior cranial vault fractures involving the frontal sinus will be presented. Contemporary techniques for repair of frontal sinus injuries will be reviewed. A treatment algorithm with illustrative cases will be presented. •Epidemiology•Embryology•Anatomy•Physiology

New methods for the evaluation and treatment of craniofacial dysostosis-associated cerebellar tonsillar herniation.

Herniation of the cerebellar tonsils may occur in children with craniofacial dysostosis (e.g., Apert, Carpenter, Crouzon, Jackson-Weiss, Pfeiffer, and Saethre-Chotzen syndromes), occasionally, with serious sequelae. Cerebellar tonsillar herniation is probably acquired in children affected with craniofacial dysostosis, raising the question, How should we be screening for this anomaly? This retrospective clinical study was undertaken to review the authors' series of what they believe to be a new surgical treatment for craniofacial dysostosis-associated cerebellar tonsillar herniation and to report their experience with a new screening technique. In an attempt to find a low-cost alternative to the use of routine magnetic resonance imaging for identifying cerebellar tonsillar herniation, the authors instituted sagittal reformatting of three-dimensional computed tomographic scans through the foramen magnum. Scans are considered positive if soft tissue is noted to extend below the foramen magnum, and all positive scans are further evaluated by magnetic resonance imaging with flow studies of the cerebrospinal fluid. These sagittally reformatted scans add no additional cost, and they seem to be highly sensitive in screening for cerebellar tonsillar herniation. Over a 13-month period, five children (one with Apert syndrome; four with Crouzon syndrome) with craniofacial dysostosis-associated cerebellar tonsillar herniation underwent isolated anterior cranial vault remodeling to treat observed brachycephaly (standard neurosurgical posterior decompression was not performed). All patients (mean age, 6 years; range, 2 to 14 years) were without the symptoms typically associated with cerebellar tonsillar herniation. Only those patients who had preoperative and postoperative magnetic resonance imaging scans were included in this review. All patients showed some improvement by the authors' magnetic imaging criteria after anterior cranial vault remodeling. Despite these findings, the authors recommend that until the anterior approach can be further studied, symptomatic children should undergo standard posterior neurosurgical decompression. The authors speculate that the presence of cerebellar tonsillar herniation may be a relative indication for decompressing the cranial vault in the craniofacial dysostoses. In addition, they propose that the descriptive anatomic term "cerebellar tonsillar herniation" be substituted for the misnomer "Chiari malformation" in these children.

Bioresorbable Fixation for Congenital Pediatric Craniofacial Surgery: A 2-Year Follow-Up

We describe our experience with the use of a polymeric biodegradable system for the correction of congenital pediatric craniofacial malformations. These fixation methods present several advantages over conventional metallic fixation systems. Our series consists of 51 patients that underwent craniofacial surgery, 46 for craniosysostosis, and 5 for encephalocele. The mean age of the patients was 3 years (median age 9 months). Patients with coronal or metopic craniosynostosis underwent a bifrontal craniotomy and anterior cranial vault and orbital reconstruction. Three patients with late sagittal synostosis underwent cranial vault reconstruction in two stages. Encephalocele defects were repaired with osteotomies, and/or onlay bone graft. Lactosorb (Lorenz Biomet, Warsaw, Ind.) plates (cut from a prefabricated mesh) and screws were employed using established fixation techniques. Cranial bone was the source of all bone graft when required. Pre- and postoperative clinical, radiographic and photographic examinations were performed on all patients. At 2 years follow-up, no evidence of infection, erythema, extrusion, instability of the bony fragments or relapse has been noted. The plates themselves were universally impalpable by the one year follow-up examination. The results in this series support the use of resorbable fixation systems in the correction of congenital craniofacial deformities.

Surgical outcomes using bioabsorbable plating systems in pediatric craniofacial surgery.

The purpose of this study was to evaluate the surgical outcomes of the 1.5-mm LactoSorb plating system (Walter Lorenz Surgical, Inc., Jacksonville, FL, U.S.A.) used to stabilize the osteotomized calvarial bone in pediatric patients who have undergone craniofacial surgery. The records of 33 consecutive pediatric patients who underwent craniofacial surgery from January 1997 through December 1997 were reviewed. There were 18 male and 15 female patients, and the age ranged from 4 months to 12 years. Patients were followed-up at 1 week, 1 month, 3 months, 6 months, and 12 months after surgery. For those patients reviewed, the following information is included: age, sex, diagnosis, surgical procedures, number and size of LactoSorb plates and screws used in each patient, operative difficulty of the screws and the heat pack, and postoperative complications, including wound healing, palpability, and infection. The LactoSorb plating system was used to stabilize the osteotomized calvarial bones in 33 patients who were diagnosed with: 1) craniosynostosis, 2) hydrocephalus, 3) fibrous dysplasia, or 4) cranial deformation. Orbital rim advancement and anterior cranial vault reshaping were performed in 17 patients. Posterior cranial vault reshaping, orbital rim advancement, and anterior cranial vault reshaping were performed in eight patients. Posterior cranial vault reshaping only was performed in seven patients. Excision of fibrous dysplasia from temporal bone was performed in one patient. One patient had a postoperative wound infection, and LactoSorb plates were palpable postoperatively in four patients. The LactoSorb plating system provided adequate rigidity for stabilizing the osteotomized calvarial bone during surgery and maintained adequate rigidity after surgery during the bone healing period before absorption. This plating system showed satisfactory results in pediatric craniofacial surgery patients.

Nasopharyngeal Airway for Guiding Nasogastric Tubes

In Response: We thank Drs. Alexander and Cooney for pointing out the single case report (their ref. 3) in which a patient with multiple facial and skull fractures had a nasopharyngeal (NP) airway placed (not by the authors of the case report) and it partially entered into the anterior cranial vault. This report points out our error in assuming that a NP airway being of short length would not likely enter the cranial vault in a patient with a basilar skull fracture. We hope that this does not distract from the main point--that a small, lubricated NP airway used as an obturator can serve to minimize NP trauma when passing a nasogastric (NG) tube and can aid in directing it toward the esophagus. We have noticed less incidence of curling of NG tubes within the oropharynx since employing this method. The authors of the aforementioned case report advocate using a reusable, longitudinally split, uncuffed red rubber tube as an obturator to assist in passage of the NG tube into the esophagus. They do not specify the size for the adult patient. An 18 Fr NG tube is approximately 7 mm in its greatest diameter. Therefore, a tube of at least 7.5-mm internal diameter would be required. Perhaps this size of red rubber tube would also reduce mucosal trauma as well as ensure easy passage of the NG into the esophagus. However, we suspect that the red rubber tubes are now in extremely short supply in the United States since the introduction of disposable plastic endotracheal tubes several years ago. The cost to restock and to establish a system to reuse them would probably be prohibitive. Therefore, for now the NP airway is the best choice. Randall W. Henthorn, MD Raghuvender Ganta, MD Department of Anesthesiology, The University of Oklahoma Health Sciences Center, College of Medicine, Oklahoma City, OK 73152

Nasopharyngeal Airway for Guiding Nasogastric Tubes

In Response: We thank Drs. Alexander and Cooney for pointing out the single case report (their ref. 3) in which a patient with multiple facial and skull fractures had a nasopharyngeal (NP) airway placed (not by the authors of the case report) and it partially entered into the anterior cranial vault. This report points out our error in assuming that a NP airway being of short length would not likely enter the cranial vault in a patient with a basilar skull fracture. We hope that this does not distract from the main point--that a small, lubricated NP airway used as an obturator can serve to minimize NP trauma when passing a nasogastric (NG) tube and can aid in directing it toward the esophagus. We have noticed less incidence of curling of NG tubes within the oropharynx since employing this method. The authors of the aforementioned case report advocate using a reusable, longitudinally split, uncuffed red rubber tube as an obturator to assist in passage of the NG tube into the esophagus. They do not specify the size for the adult patient. An 18 Fr NG tube is approximately 7 mm in its greatest diameter. Therefore, a tube of at least 7.5-mm internal diameter would be required. Perhaps this size of red rubber tube would also reduce mucosal trauma as well as ensure easy passage of the NG into the esophagus. However, we suspect that the red rubber tubes are now in extremely short supply in the United States since the introduction of disposable plastic endotracheal tubes several years ago. The cost to restock and to establish a system to reuse them would probably be prohibitive. Therefore, for now the NP airway is the best choice. Randall W. Henthorn, MD Raghuvender Ganta, MD Department of Anesthesiology, The University of Oklahoma Health Sciences Center, College of Medicine, Oklahoma City, OK 73152

The Detection and Management of Intracranial Hypertension after Initial Suture Release and Decompression for Craniofacial Dysostosis Syndromes

We performed a retrospective study of 107 consecutive patients with syndromic forms of craniosynostosis (craniofacial dysostosis) seen by the craniofacial team at the Hospital for Sick Children between 1986 and 1992. There were 51 patients with Crouzon's syndrome, 33 with Apert's syndrome, 8 with Pfeiffer syndrome, 11 with Saethre-Chotzen syndrome, and 4 with kleeblättschadel anomaly. Six patients developed raised intracranial pressure (ICP) after initial suture release and decompression (Apert's syndrome, three patients; Pfeiffer syndrome, one patient; Saethre-Chotzen syndrome, two patients). Raised ICP was considered in those children who returned with a bulging fontanelle, progressive frontal bone protrusion, intermittent headaches, irritability, and vomiting. The diagnosis of raised ICP was based on papilledema (four patients), progressive macrocephaly (one patient), and ICP monitoring (one patient). No child in this group had hydrocephalus requiring cerebrospinal fluid diversion. Once raised ICP was detected in these children, a second operation was immediately performed to reduce the ICP with the intention of expanding the volume of the cranial cavity. The second procedures included: anterior cranial vault and upper orbital reshaping (four patients), posterior cranial vault reshaping (one patient), and total cranial vault reshaping (one patient). There were no perioperative complications in these patients, although one patient showed subsequent recurrence of raised ICP requiring further cranial vault re-expansion. At follow-up, ranging from 3 to 7 years, all six patients were asymptomatic without evidence of raised ICP. In our series, raised ICP occurred in 6% of the children with a craniofacial dysostosis syndrome after initial suture release and decompression.(ABSTRACT TRUNCATED AT 250 WORDS)

Cranio-Orbito-Zygomatic Measurements from Standard CT Scans in Unoperated Treacher Collins Syndrome Patients: Comparison with Normal Controls

Fourteen reproducible cranio-orbito-zygomatic measurements taken from 26 standard axial computed tomographic (CT) scans of unoperated individuals with symmetric forms of Treacher Collins syndrome (TCS) were compared to age-matched controls. The interorbital measurements of the TCS patients were at the mean when compared to their cohort group (medial and lateral orbital wall separation), while the zygomatic measurements were significantly less than normal confirming the extent of malar hypoplasia. The congenitally deficient lateral aspect of the orbits in TCS patients was confirmed by the greater than normal values measured for globe protrusion and medial orbital wall protrusion in conjunction with the diminished lateral orbital wall lengths, all of which use the lateral orbital rim as a reference point. The abnormal shape of the anterior cranial vault in patients with TCS was documented as a diminished intercoronal distance (width) and decreased cephalic length when compared to normal age-matched controls.

Cranio-Orbito-Zygomatic Measurements from Standard CT Scans in Unoperated Treacher Collins Syndrome Patients: Comparison with Normal Controls

Fourteen reproducible cranio-orbito-zygomatic measurements taken from 26 standard axial computed tomographic (CT) scans of unoperated individuals with symmetric forms of Treacher Collins syndrome (TCS) were compared to age-matched controls. The interorbital measurements of the TCS patients were at the mean when compared to their cohort group (medial and lateral orbital wall separation), while the zygomatic measurements were significantly less than normal confirming the extent of malar hypoplasia. The congenitally deficient lateral aspect of the orbits in TCS patients was confirmed by the greater than normal values measured for globe protrusion and medial orbital wall protrusion in conjunction with the diminished lateral orbital wall lengths, all of which use the lateral orbital rim as a reference point. The abnormal shape of the anterior cranial vault in patients with TCS was documented as a diminished intercoronal distance (width) and decreased cephalic length when compared to normal age-matched controls.

Apert Syndrome

We reviewed our experience with eight infants or young children (less than 2 years of age) who presented sequentially with Apert syndrome. Using a method of 14 measurements taken from the cranio-orbitozygomatic region in preoperative and postoperative CT scans of these patients, we documented their presenting skeletal morphology and the results of surgical correction at least 1 year after surgery. Significant preoperative findings included a wide anterior cranial vault at 110 percent of normal, a maximum cranial length that averaged only 90 percent of normal, a substantially widened anterior interorbital distance of 117 percent of normal, an increased lateral interorbital distance (112 percent of normal), and a widened bitemporal width at 122 percent of normal. Globe protrusion was significant at 121 percent of normal, and the medial orbital wall distance (length) was less than normal at 92 percent. In the upper midface (zygomatic) region, both the distance between the zygomatic buttresses and the interarch distance were found to be increased at 109 percent of normal, while the zygomatic arch lengths were substantially shortened at 79 percent of normal. Results of surgical correction, as documented by CT scan measurements, showed that more than a year after surgery, skeletal morphology had changed from preoperative measurements but that none of the craniofacial measurements had significantly improved (p < 0.05) in comparison with those of age-matched controls. Quantitative measurement of CT scans of the cranio-orbitozygomatic region confirmed clinically observed findings in these patients before cranio-orbital reconstruction in infancy and early childhood and proved useful in assessing the surgical results over time.

Metopic Synostosis

Our study applied a method of using 14 clinically relevant measurements of CT scan images to document skeletal dysmorphology in patients with metopic synostosis to determine the effectiveness of their surgical procedure after a minimum of 1 year. Ten consecutive patients with metopic synostosis who underwent a standard surgical procedure were reviewed. Preoperative and postoperative (>1 year) CT scans were compared with those of age-matched controls. Percentages of normal were then compared for significant differences. Preoperative cranial vault measurements revealed a narrowed anterior inter-coronal distance at 92 percent of normal. Orbital measurements showed a narrowed anteromedial wall interorbital distance at 79 percent of normal, a narrowed lateral orbital wall distance at 94 percent, and an elevated medial orbital wall protrusion beyond the plane of the lateral orbital walls at 115 percent. After surgery, the intercoronal distance was significantly corrected to 101 percent, the anteromedial wall interorbital distance was improved but remained undercorrected at 90 percent, and the medial wall protrusion was significantly decreased to 98 percent of normal. Quantitative measurements of CT scan images confirmed clinically observed physical findings in unoperated trigonocephaly to be orbital hypotelorism, retruded lateral orbital rims, and a narrowed bitemporal width. The surgical technique corrected the lateral orbital wall aspects of the deformity as well as the narrowed anterior cranial vault width and improved the orbital hypotelorism. (Plast. Reconstr. Surg. 93: 16, 1994.)

Crouzon Syndrome

We reviewed our experience with 14 children who presented sequentially with untreated Crouzon syndrome and whose cranial vault presentation was with bilateral coronal synostosis. Using a method of 14 measurements in the cranio-orbitozygomatic region taken from preoperative and postoperative CT scans in these patients, we documented their presenting skeletal morphology and the results of surgical correction at least 1 year after operation. Our preoperative measurements confirmed a widened anterior cranial vault at 108 percent of normal and a cranial length averaging only 92 percent of normal. In comparison with age-matched controls, orbital measurements revealed a widened anterior interorbital distance at 122 percent of normal, an increased intertemporal width at 121 percent of normal, globe protrusion at 119 percent of normal, and a short medial orbital wall distance at only 86 percent of normal. The distance between the zygomatic buttresses and the interarch distance were found to be increased at 106 and 103 percent of normal, respectively. The zygomatic arch lengths were substantially shortened at only 87 percent of age-matched control values. These findings confirmed clinical observations of brachycephalic anterior cranial vaults with shallow, hyperteloric orbits and globe proptosis. Generally, in these patients the midface is horizontally retrusive and transversely wide, reflected in wide and shortened zygomas. Assessment of the postoperative results at least 1 year later showed no significant changes in any craniofacial measurements. Our findings indicate that early surgical attempts to decompress and reshape the cranio-orbital regions may limit the effects of increased intracranial pressure but do not correct the deformity as judged by CT scan evaluation at least 1 year later. Over the period of the study, the Crouzon deformity did not worsen after surgery, but the measurements remained far from normal.

Frontal sinus osteoma.

Osteoma is the most common benign tumor of the nose and paranasal sinuses, and the frontal sinus is its most frequent location. This tumor may be discovered incidentally on radiographs or may enlarge to produce symptoms and, rarely, complications referable to its location near the orbit and anterior cranial vault. A series of 22 cases of frontal sinus osteoma treated at the UCLA Center for the Health Sciences is reviewed. The presenting symptoms of this tumor, patient examination, radiographic evaluation, diagnosis, and indications for surgical and nonsurgical management are discussed. Various surgical approaches are reviewed, with emphasis on the advantages and disadvantages of each technique. Issues at surgery include the location of the surgical incision, technique of sinus entry, tumor removal, status of the posterior sinus table, patency of the nasofrontal duct, sinus obliteration, and avoidance of cosmetic deformity. Patient outcomes are assessed and recommendations given based on our findings and experience.

Transposition cranioplasty to restore forehead contour in craniofacial deformities

THE oxycephaly (acrocephaly, turricephaly) seen in the various types of craniofacial dysostosis often includes high facial stenosis and marked frontal bossing so that the forehead profile is quite abnormal, This includes retrusion or hypoplasia of the supraorbital ridges, a flat bony forehead and a towering anterior cranial vault. In addition, there may be frontal and supra-orbital asymmetry which becomes less marked in the vault region. A number of remedies to correct the frontal contour have been proposed: onlay bone grafting and frontal bone advancement (Tessier, 1971), acrylic cement alone or in combination with bone grafts (Edgerton, 1975), 180” reversal of the entire upper cranium (Munro, 1976) and pedicle transposition of frontal bone (Stricker et al., 1972). After an experience of many of these procedures, frontal transposition cranioplasty has become our method of choice; it is relatively simple to perform and gives consistently good results without complications. It can be incorporated with ease into correction of hypertelorism and mid or upper face retrusion.