Fractures of the floor of the anterior cranial fossa

Osteointegration of a bisphenol-a-glycidyl-dimethacrylate composite and its use in anterior skull base defects: an experimental study in an experimental design model of cerebrospinal fluid leak

OBJECT

Promising clinical results were reported in watertight closure of anterior skull base defects (ASBDs) with bisphenol-a-glycidyl-dimethacrylate (bis-GMA)-based materials to prevent the cerebrospinal fluid leaks. However, interrelation of these materials with surrounding bones in histologic level, referred to as the osteointegration, has not been reported in the anterior skull base. In addition, an illustrative case with an ASBD that was repaired using a bis-GMA composite has been presented.

METHODS

Twenty New Zealand rabbits were divided into 4 groups: control and sham groups consisted of 2 and 6 rabbits, respectively. The "skull base defect" group (n = 6) underwent a unifrontal craniectomy and an iatrogenic ASBD followed by creating a dural defect to obtain a cerebrospinal fluid leak. Similar bony and dural defects were acquired in the "repair with bis-GMA based allograft" group (n = 6), but the bony defect was closed with bis-GMA-based allograft.

RESULTS

All animals in the "skull base defect" group died in 3 weeks after surgery. There were no animal losses in the "repair with bis-GMA based allograft" group at the sixth month. Histologic evaluation revealed complete osteointegration of bis-GMA composite with surrounding bones.

CONCLUSIONS

bis-GMA based allograft achieved a watertight repair of the ASBD. Histologic findings of this study showed that bis-GMA composite is a reliable material to be used in the closure of anterior skull base bony defects.

Immediate single-stage reconstruction of complex frontofaciobasal injuries: Part II

OBJECTIVES

The purpose of this prospective study was to identify selection criteria for immediate single-stage reconstruction in patients with severe complex craniofacial trauma to improve their functional outcome and reduce complications.

PATIENTS AND METHODS

In this series, 24 new patients (16 men and 8 women) were added to our previous group (26 patients) with an age range from 10 to 55 years with mean of 26 years and Glasgow Coma Scale scores of 5-13; all patients had a combined single-stage repair of their complex craniofacial injuries within 6 h of their admission. We added some modifications to our standard technique using three-dimensional computed tomography, intracranial pressure monitoring, and support of dural repair/graft using dural patch and glue. The esthetic facial outcome was evaluated by an independent plastic assessor based on objective scale criteria. This series was carried out in Prince Salman Military Hospital between November 2010 and September 2013.

RESULTS

Early neurosurgical outcome was considered good in 22/24 patients (92%), moderate in one patient (4%), and poor in the last one (4%). At late evaluation, 20 cases (83%) regained their consciousness without any cognitive deficit. One patient (4%) remained in neurovegetative status. Early esthetic outcome was considered to be excellent in 18/24 patients (75%), good in 3 patients (12.5%), deemed fair in 2 patients (8%), and labeled poor in only 1 patient (4%). At late evaluation, the patient labeled fair had improved to good with topical scar management and the patient deemed poor had improved to fair with two successive plastic procedures. Complications included a cerebrospinal fluid leak in 2 patients (8%), one was managed conservatively and the second was treated surgically with intra- and extradural grafting.

CONCLUSION

In complex frontofaciobasal injuries, successful facial repair depends on immediate and definitive reconstruction. However, improved neurological outcomes in these patients depend on judicious selection of the appropriate candidates from severely head-injured patients.

Intracranial repair of posttraumatic cerebrospinal fluid rhinorrhea associated with recurrent meningitis

OBJECTIVE

The purposes of this study are to assess the efficacy of our intracranial surgery and evaluate the association between failure after first surgical repair and the risk factors that have been applied on a group of 13 patients affected by posttraumatic cerebrospinal fluid rhinorrhea associated with recurrent meningitis.

METHODS

We retrospectively collected data on 13 patients referred to our institution. All patients had history of head trauma and experienced 2 or more episodes of meningitis.

RESULTS

Three of the 13 patients had craniectomy defect due to previous trauma and surgery, 9 patients had linear fracture, and 1 patient had no apparent fracture line on preoperative radiologic evaluation. Ten of the 13 patients had identified frontal bone fracture involving the frontal sinus during surgery. Dural tear was identified intradurally and was repaired using a fascia lata graft with or without fibrin glue. Fibrin glue was applied over the suture in 7 patients. Three of the 13 patients had large dural defects.

CONCLUSIONS

The size of bone and dural defect seems to be an important prognostic factor of episodes of meningitis. The use of fibrin glue to fixate fascia lata graft did not benefit the outcome.

Immediate single-stage reconstruction of complex frontofaciobasal injuries: part I

Objective To determine if immediate (within 6 hours of adequate resuscitation) single-stage repair of complex craniofacial injuries could be accomplished with acceptable morbidity and mortality taking into consideration the cosmetic appearance of the patient. Patients and Methods A total of 26 patients (19 men, 7 women) ranging in age from 8 to 58 years with Glasgow Coma Scale scores of 5 to 15 all had a combined single-stage repair of their complex craniofacial injuries within 6 hours of their admission. After initial assessment and adequate resuscitation, they were evaluated with three-dimensional computed tomography of the face and head. Coronal skin flap was used for maximum exposure for frontal sinus exenteration as well as dural repair, cortical debridement, calvarial reconstruction, and titanium mesh placement. Results Neurosurgical outcome at both the early and late evaluations was judged as good in 22 of 26 patients (85%), moderate in 3 of 26 (11%), and poor in 1 of the 26 (3.8%). Cosmetic surgical outcome at the early evaluation showed 17 of 26 (65%) to be excellent, 4 of 26 (15.5%) to be good, 4 patients (15.5%) to be fair, and 1 patient (3.8%) to be poor. At the late reevaluation, the fair had improved to good with an additional reconstructive procedure, and the poor had improved to fair with another surgery. There was no calvarial osteomyelitis, graft resorption, or intracranial abscess. Complications included three patients (11%): one (3.8%) had tension pneumocephaly and meningitis, one (3.8%) had delayed cerebrospinal fluid leak with recurrent attacks of meningitis, and one had a maxillary sinus infection (3.8%) secondary to front maxillary fistula. Conclusion The immediate single-stage repair of complex craniofacial injuries can be performed with acceptable results, a decreased need for reoperation, and improved cosmetic and functional outcomes.

A comparative study of cranial, blunt trauma fractures as seen at medicolegal autopsy and by computed tomography

Background

Computed Tomography (CT) has become a widely used supplement to medico legal autopsies at several forensic institutes. Amongst other things, it has proven to be very valuable in visualising fractures of the cranium. Also CT scan data are being used to create head models for biomechanical trauma analysis by Finite Element Analysis. If CT scan data are to be used for creating individual head models for retrograde trauma analysis in the future we need to ascertain how well cranial fractures are captured by CT scan. The purpose of this study was to compare the diagnostic agreement between CT and autopsy regarding cranial fractures and especially the precision with which cranial fractures are recorded.

Methods

The autopsy fracture diagnosis was compared to the diagnosis of two CT readings (reconstructed with Multiplanar and Maximum Intensity Projection reconstructions) by registering the fractures on schematic drawings. The extent of the fractures was quantified by merging 3-dimensional datasets from both the autopsy as input by 3D digitizer tracing and CT scan.

Results

The results showed a good diagnostic agreement regarding fractures localised in the posterior fossa, while the fracture diagnosis in the medial and anterior fossa was difficult at the first CT scan reading. The fracture diagnosis improved during the second CT scan reading. Thus using two different CT reconstructions improved diagnosis in the medial fossa and at the impact points in the cranial vault. However, fracture diagnosis in the anterior and medial fossa and of hairline fractures in general still remained difficult.

Conclusion

The study showed that the forensically important fracture systems to a large extent were diagnosed on CT images using Multiplanar and Maximum Intensity Projection reconstructions. Difficulties remained in the minute diagnosis of hairline fractures. These inconsistencies need to be resolved in order to use CT scan data of victims for individual head modelling and trauma analysis.

SURGICAL MANAGEMENT OF ANTERIOR CRANIAL BASE FRACTURES WITH CEREBROSPINAL FLUID FISTULAE

OBJECTIVE

The management of cerebrospinal fluid (CSF) fistulae after anterior cranial base fracture remains a surgical challenge. We reviewed our results in the repair of CSF fistulae complicating multiple anterior cranial base fractures via a combined intracranial extradural and intradural approach and describe a treatment algorithm derived from this experience.

METHODS

We retrospectively reviewed the files of 209 patients with an anterior cranial base fracture complicated by a CSF fistula who were admitted between 1980 and 2003 to Liège State University Hospital. Among those patients, 109 had a persistent CSF leak or radiological signs of an unhealed dural tear. All underwent the same surgical procedure, with combined extradural and intradural closure of the dural tear.

RESULTS

Of the 109 patients, 98 patients (90%) were cured after the first operation. Persistent postoperative CSF rhinorrhea occurred in 11 patients (10%), necessitating an early complementary surgery via a transsphenoidal approach (7 patients) or a second-look intracranial approach (4 patients). No postoperative neurological deterioration attributable to increasing frontocerebral edema occurred. During the mean follow-up period of 36 months, recurrence of CSF fistula was observed in five patients and required an additional surgical repair procedure.

CONCLUSION

The closure of CSF fistulae after an anterior cranial base fracture via a combined intracranial extradural and intradural approach, which allows the visualization and repair of the entire anterior base, is safe and effective. It is essentially indicated for patients with extensive bone defects in the cranial base, multiple fractures of the ethmoid bone and the posterior wall of the frontal sinus, cranial nerve involvement, associated lesions necessitating surgery such as intracranial hematomas, and post-traumatic intracranial infection. Rhinorrhea caused by a precisely located small tear may be treated with endoscopy.

Nomenclature of Frontobasal Trauma: A New Clinicoradiographic Classification

BACKGROUND

High-velocity accidents cause significant injury to the cranial and facial skeleton. Frontobasal fractures include fractures of the upper third of the face and anterior skull base. The pattern and classifications of these fractures are poorly understood at present. The authors have attempted a new comprehensive classification based on detailed clinicoradiographic evaluation.

METHODS

A prospective study was undertaken in a tertiary care hospital in 1 calendar year (July of 2000 to June of 2001). All 63 patients with frontobasal fractures had detailed clinical and radiographic evaluation with plain radiographs and high-resolution computed tomographic scan. The fractures were classified as frontal, basal, and combined. Areas were separated as central (designated type 1) and lateral (designated type 2) to differentiate the pattern in the sagittal plane according to the site of impact. Combined fractures involving both central and lateral areas were designated type 3. These could be further classified into unilateral or bilateral or pure or impure, depending on the absence or presence of midfacial fractures.

RESULTS

The fractures were subdivided into nine types considering the whole lateral and anteroposterior extents of the frontobasal region. The most common was the combined frontobasal type (30.16 percent). We found the pure type in 38.1 percent (24 of 63) and the impure type in 61.9 percent (39 of 63) of patients. Cerebrospinal fluid leaks occurred more commonly in impure types of frontobasal fracture. Blunt trauma leading to closed frontobasal fracture was seen in 35 patients. Penetrating trauma with open fractures was found in 28 patients and cerebrospinal fluid leak through the wound was seen in six of them.

CONCLUSIONS

The new comprehensive classification clearly defines the anatomical areas within the frontobasal region, the nature of injury, and its association with midfacial injuries, and is helpful in planning the approach to their exposure in surgery.