Craniofacial Surgery

McKay McKinnon and David M. Frim General Principles

Craniofacial procedures include a variety of orthopedic and soft tissue operations that are performed in and around the brain, orbit and nasopharynx. A craniofacial reconstructive procedure, whether for congenital malformation or tumor, is optimally performed by an interdisciplinary team composed of a craniofacial surgeon and a neurosurgeon. As a rule, communication and cooperation between the surgical team and the pediatric anesthesiologist is the key to a successful outcome. As a discipline, craniofacial surgery addresses 3 major groups of disorders: (1) the craniosynostoses and craniofacial syndromes; (2) craniofacial clefts and congenital anomalies of the skull base; and (3) tumors; as well as traumatic injury.

Craniosynostosis and Craniofacial Syndromes


Craniosynostosis is defined as the premature closure of the cranial sutures, which includes the paired coronal suture, the paired lambdoidal suture and the midline metopic and sagittal sutures. Nonsyndromic (isolated) craniosynostosis occurs sporadically, although a few families are known where the disorder is inherited in an autosomal dominant pattern. The genetic cause for most craniofacial syndromes such as Crouzon's, Apert's and Pfeiffer's syndromes has been localized to the gene family coding for fibroblast growth factor receptor (FGFR). Mutations occurring in different parts of the FGFR gene, as well as in several related genes, probably account for the different phenotypes that are observed.

Nonsyndromic Craniosynostosis


Premature closure of one or any combination of the cranial sutures produces a stereotypical change in head shape that is generally easily recognized during the physical examination (Table 1). The development of a characteristic head shape follows a general principle in which growth of the head is restricted in the direction perpendicular to the synostotic suture, and compensatory growth occurs in a direction parallel to the closed suture. Although the primary abnormality in craniosynostosis is premature closure of the suture, it is normal brain growth that causes the secondary change in head shape. For this reason, craniosynostosis may not be apparent at birth, but will become more apparent during the first few months of life when brain and head growth are particularly rapid. This basic concept is not well understood by many practitioners.

Pediatric Neurosurgery, edited by David Frim and Nalin Gupta. ©2006 Landes Bioscience.

Table 1. Types of craniosynostosis

Suture Cranial Abnormality Features



Scaphocephaly, dolichocephaly

Unilateral Anterior coronal plagiocephaly

Bilateral Brachycephaly coronal

Metopic Trigonocephaly

Lambdoid Posterior plagiocephaly

Anterior to posterior elongation, 40-60% narrow biparietal distance, frontal and/or occipital bossing

Recession of the ipsilateral 20-30%

forehead, elevation of the ipsilateral eye, hollowing of the ipsilateral temporal fossa

'Tower-like' pointed head, 10%

reduced overall size in the anterior to posterior dimension, flattened forehead

Pointed frontal bone, hypotelorism, 5-10% recession of the lateral brow

Flattening of the occipital area, prominence of the contralateral frontal area

Closure of the sagittal suture, the most common type of synostosis, will restrict head growth in the side-to-side (biparietal) direction and allow growth in the anterior-to-posterior direction (Fig. 1). This produces a long, narrow, boat-shaped head that is termed dolichocephalic. From the side, the head appears to be elongated and rounded superiorly, a shape of the head called scaphocephalic, which is synonymous with dolichocephaly. Unilateral coronal synostosis will produce an asymmetry

Figure 1. A reformatted 3D CT scan image of a child with sagittal synostosis viewed from above. Note the absence of the sagittal suture and the elongated head. The frontal area is particularly prominent, a feature described as 'frontal bossing'.

Figure 1. A reformatted 3D CT scan image of a child with sagittal synostosis viewed from above. Note the absence of the sagittal suture and the elongated head. The frontal area is particularly prominent, a feature described as 'frontal bossing'.

Figure 2. Reformatted 3D CT scan images of a child with unilateral coronal synostosis. The involved supraorbital area is recessed leading to an impression of a proptotic eye, which is actually in a normal position.

in the development of the orbit, along with lack of growth in the temporal region on the affected side. The forehead will tend to be recessed and the brow elevated, also on the affected side (Fig. 2). The effect upon the orbit is best seen on an anterior-posterior (AP) skull film, with elevation and pointing of the lateral orbit resulting in a shape described as a 'harlequin eye' (Fig. 3). The overall asymmetry of the head is described as anterior plagiocephaly. Synostosis ofboth coronal sutures will restrict the head growth in the anterior-to-posterior direction and will produce a head shape that is reduced in the anterior-to-posterior direction and widened in the side-to-side (biparietal) direction (Fig. 4). This appearance is described as brachycephaly. Lambdoid synostosis produces occipital asymmetry, and is also described as posterior plagiocephaly (Fig. 5). If

Figure 3. An AP skull X-ray film showing a characteristic elevation of the lateral orbit with a unilateral coronal synostosis. This is known as a 'harlequin eye' deformity.
Figure 4. A reformatted 3D CT scan image of a child with bicoronal synostosis. Viewed from the side, the head is markedly short in the anterior to posterior direction and elongated upwards.

both lambdoidal sutures are closed, then the entire occiput will be foreshortened and the biparietal diameter widened. Early closure of the metopic suture limits side-to-side growth of the forehead, resulting in hypotelorism, recession of the lateral forehead bilaterally, and a triangular-shaped forehead when viewed from above. This head shape is described as trigonocephaly (Fig. 6).

Posterior plagiocephaly can also occur from positioning infants in the supine position. Based upon recommendations from national organizations to prevent sudden

Figure 5. A reformatted 3D CT scan images of a child with right lambdoid synostosis. From above (left image), the left occipital area is prominent. The marked deformation of the posterior portion of the cranial vault is particularly evident when viewed from below (right image).

Figure 6. A reformatted 3D CT scan image of a child with metopic synostosis. Viewed from above, the forehead is pointed, or 'triangular', with associated recession of the lateral supraorbital margins and varying degrees of hypotelorism.

infant death syndrome (SIDS), there has been a dramatic increase in the development of positional plagiocephaly. This cranial vault deformity is due to molding of the head resulting from asymmetric pressure on the occiput. There are clear differences between plagiocephaly resulting from synostosis and from positioning (Table 2).

Table 2. Differentiating positional plagiocephaly from true lambdoid suture synostosis

Feature Positional Plagiocephaly

Lambdoid Suture Synostosis



Position of ears



Flattening of the side of sleep preference

At times present at birth, but usually accentuated with back sleeping during first three months; improvement or stability thereafter

From above, ipsilateral ear is displaced anteriorly

Ipsilateral forehead is displaced anteriorly; degree of displacement is usually much less than posterior flattening

Posterior plagiocephaly

Anterior to posterior elongation, narrow biparietal distance, frontal and/or occipital bossing

Gradual worsening of cranial deformity with no clear association with sleeping preference

'Tower-like' pointed head, reduced overall size in the anterior to posterior dimension, flattened forehead

Ipsilateral forehead is usually displaced posteriorly due to lack of growth at lambdoid area; contralateral forehead is usually displaced forward

Flattening of the occipital area, prominence of the contralateral frontal area

Patients with single-suture craniosynostosis are rarely symptomatic, as the overall volume of the cranium is normal. Typical signs of raised intracranial pressure (ICP) such as nausea, vomiting and lethargy are not observed. Some authors have suggested that these patients demonstrate a variety of cognitive deficits, but this observation is not proven. Once the abnormal head shape is recognized, the patient should be evaluated at a center with experience managing craniofacial anomalies. Skull films are generally of limited use for diagnosis because of difficulty in evaluating the sutures adequately and the variable techniques used. If the diagnosis is in doubt, then a high-resolution computed tomography (CT) scan with three-dimensional reformatting is helpful.


The preferred treatment for craniosynostosis is surgery, although, rarely, some parents will choose not to have their child undergo surgery. These children ultimately develop cranial vault deformities of varying severity, but do not appear to have neurological or cognitive deficits.

Surgical treatment for nonsyndromic craniosynostosis has changed over time. The original procedure consisted of a simple craniectomy of the involved suture without a significant recontouring of the cranial vault. Because of persisting deformities in some patients, this technique has been gradually supplanted by a variety of more extensive procedures that remove the suture but also reconstruct the cranial vault to correct the secondary head-shape change. Although difficult to prove with objective measures, the use of these more extensive procedures does appear to create a more consistent correction when compared to simple suturectomy. In the past few years, endoscope-assisted surgery has been used to reduce the blood loss and morbidity of larger open procedures. These endoscopic procedures can be done safely in very young infants (less than 3 months of age), and when coupled with a postoperative molding helmet can result in an excellent final appearance.

Surgical Technique

Surgical treatment of any synostotic condition is tailored to the affected suture and the degree of secondary cranial vault abnormality. In general, the exposure must allow access to the entire affected area as well as to a significant portion of the surrounding calvarium. Careful preoperative planning must include a discussion of which bones are to be removed, whether or not the supraorbital rim requires reconstruction, and if decompression of neural structures is required. If the operation is on the metopic or the coronal sutures, the exposure will need to be biased anteriorly. If the operation is on the sagittal suture or the lambdoidal suture, the exposure will need to be biased more posteriorly, although at times the frontal region may also require reconstruction. For virtually all forms of coronal suture synostosis, the supraorbital rim will require removal and reconstruction.

A zigzag bicoronal skin incision allows access to the entire cranial vault from the orbital margin to the occiput and produces an excellent cosmetic result. After the incision is open, the synostotic suture is exposed and burr holes are placed to allow removal of the synostotic bone. There are multiple techniques for bone removal and reconstruction, which are beyond the scope of this discussion. In brief, the primary

goal of sagittal synostosis repair is the removal of the suture and wide removal of the parietal bone plates to allow the biparietal distance to be increased. This may be accomplished by creating 'barrel-stave' osteotomies in the parietal bones and then bending or fracturing the parietal segments outward. Some children will have very prominent frontal bossing, which may also require recontouring of the frontal bones. Similary, a very prominent occipital bone may also require removal and recontouring.

For metopic suture synostosis the entire frontal bone and the supraorbital rim are removed for the reconstruction of the frontal bone and the orbits. For bilateral coronal synostosis, it is necessary to remove the frontal bones, the supraorbital rim, and sometimes the parietal bones; leaving a strut of bone to cover the superior sagittal sinus. The cranial vault is reconstructed in order to increase the anterior-posterior diameter and decrease the biparietal diameter. For lambdoid synostosis, the occipital bone and the posterior portion of the parietal bone are removed on the involved side, although it is often required to remove the entire occipital bone in order to achieve a satisfactory result.

There is no universal methodology for fixation of the bony fragments, although the current trend is to use absorbable plating systems that generally disappear over 6 to 18 months. Postoperatively, after the skin is brought back together, subgaleal drains can be left in place, as postoperative facial and cranial swelling can be impressive. These drains are generally removed after 48 hours. Some infants may benefit from protective helmets for approximately 6 weeks in the postoperative period. These customized helmets can also improve the final cosmetic result by passively molding the cranial vault and preventing unexpected positional changes.


Intraoperative complications include dural lacerations, cerebrospinal fluid (CSF) leakage, dural venous sinus lacerations and, infrequently, brain injury. Delayed complications include wound infection, CSF pseudomeningoceles, and bone resorption with persistent defects in the bone. Avoidance of dural laceration is sometimes impossible given the thin nature of the dura at the skull base. Primary or secondary repair with pericranium is successful in most cases. Lacerations of the dural sinuses can lead to catastrophic hemorrhage, and rapid occlusion of the opening with he-mostatic agents is imperative. Other surgical complications include optic nerve injury and early closure of the reconstructed bone, requiring additional surgery.

Although infants recover fully within a 6-week period, a transient developmental delay (such as a delay in sitting or standing) related to the effects of the procedure may occur. A repeat craniofacial CT scan in the 6- to 12-week range and yearly visits until the children reach school age, ensure that the cosmetic result is acceptable. A repeat imaging study is not mandatory and clinical follow-up is sufficient in many situations.

Craniofacial Syndromes Diagnosis

Although almost 100 described clinical syndromes are associated with cranio-synostosis, the 4 most common are Crouzon's, Apert's, Pfeiffer's and Saethre-Chotzen

Table 3. Features of syndromic craniosynostoses


Common Features

Incidence and Genetics




Brachycephaly; coronal, lambdoid 1/25000 births and basilar suture involvement Hypertelorism Maxillary hypoplasia with midface retrusion High arched palate Mental retardation rare

Turribrachycephaly; involvement of bilateral coronal, lambdoid, and sometimes sagittal sutures Orbital hypoplasia and hypertelorism Maxillary hypoplasia Complete and symmetric syndactyly of the 2nd, 3rd, and 4th fingers Mental retardation more common

Turribrachycephaly; involvement of bilateral coronal and frontosphenoidal sutures Cloverleaf deformity common Broad thumbs and great toes Soft tissue syndactyly of some fingers

Orbital hypoplasia and hypertelorism Maxillary hypoplasia Types I, II and III described; Types II and III are associated with severe CNS anomalies while mental function is normal in Type I

FGFR2 mutation, rarely FGFR1 Autosomal dominant Equal numbers of sporadic and familial cases

1/100,000 births FGFR2 mutation Autosomal dominant Mainly sporadic with some familial cases

1/200,000 births

FGFR? and FGFR2 mutations identified Autosomal dominant Equal numbers of sporadic and familial cases



Low set hairline

Facial asymmetry; ptosis;

low-set ears Partial soft tissue syndactyly, usually 2nd and 3rd digits Mental retardation rare

1/50,000 births TWIST gene mutation Autosomal dominant with complete penetrance and incomplete expression Mainly familial cases

syndromes (Table 3). All of these syndromes visually exhibit bilateral coronal synostosis, as well as variable effects on the face. There is a stereotypic head and face dysmorphism in children who are affected by these syndromes, which usually leads to early diagnosis in infancy. Initial evaluation includes a complete neurological examination, ophthalmological testing, Hertel exophthalmometry, and a detailed dental and maxillofacial assessment. Children with Apert's syndrome also have syndactyly involving the hands and feet, which requires a number of procedures to increase the functional usefulness of the hands (Fig. 7). Additional evaluation by a speech therapist is important to evaluate oropharyngeal function and its effect on

Figure 7. A child with Apert's syndrome demonstrating bilateral syndactyly. The individual metatarsal bones are present, but abnormal, and the soft tissues are fused together.

speech. Genetic testing is also indicated, followed by family counseling. Finally, a nuanced evaluation of the psychological impact of the facial anomaly and multiple surgical procedures is essential.

Raised ICP is a common finding in children with syndromic synostosis. As a group, approximately 10% will require placement of a VP shunt. The etiology of raised ICP is presumed to be restriction of cranial-vault growth, or from hydroceph-alus. In the former case, children may present with papilledema and headaches, and with normal or small ventricular size. Microcephaly caused by a lack of cranial-vault growth over time is the usual indicator of this disorder. Hydrocephalus occurs in approximately 30% of children with Crouzon's syndrome and less frequently for the other 3 syndromes. Progressive hydrocephalus should be differentiated from ventricular dilatation, which is common in syndromic craniosynostosis patients.

Children with severe forms of Pfeiffer's syndrome and children with cloverleaf skull deformities (Fig. 8) are at higher risk for hydrocephalus. These children can present with more typical signs and symptoms of raised ICP, such as headache, irritability, a bulging fontanelle, extra-ocular movement abnormalities and/or papille-dema. The usual cause is microcephaly resulting from the closure of multiple sutures. These patients require a cranial-vault expansion and reconstruction soon after birth.

Treatment and Surgical Technique

The general principles of craniofacial repair are early cranial-vault repair (between 6 to 9 months of age) to allow for more-normal brain growth, and delayed repair of facial structures (between 5 to 8 years of age) such as the orbit, maxilla, and mandible to address problems of cosmesis, orbital position, dental occlusion and pharyngeal function. Multiple procedures may be required during childhood for

Figure 8. A reformatted 3D CT scan images of a child with a clover-leaf cranial vault abnormality. The shape is very abnormal, with towering of the cranial vault in the midline and lateral protrusion of the temporal bones. The bones are very thin due to the outward growth of the brain, resulting in an irregular appearing cranial vault.

Figure 8. A reformatted 3D CT scan images of a child with a clover-leaf cranial vault abnormality. The shape is very abnormal, with towering of the cranial vault in the midline and lateral protrusion of the temporal bones. The bones are very thin due to the outward growth of the brain, resulting in an irregular appearing cranial vault.

severe anomalies. Other procedures may be required to treat problems such as prop-tosis and airway obstruction. Early symptomatic hydrocephalus will require placement of a ventriculoperitoneal (VP) shunt in a minority of patients; in those with primary cranial-vault restriction, expansion of the cranial vault during the initial surgical procedure may address some of the problem. Others may require placement of a shunt if hydrocephalus becomes symptomatic at a later date. Imaging studies are rarely required to establish a diagnosis, but are very useful as preoperative adjuncts. A magnetic resonance imaging (MRI) study of the brain and upper cervical spine can exclude the presence of a significant Chiari I malformation, which can coexist with other posterior fossa anomalies.

In addition to general preoperative blood tests, nearly all craniofacial reconstructive procedures in infants will require a blood transfusion, and issues related to risks of blood transfusion should be discussed directly with the family. Since most syndromic synostoses involve the coronal sutures, the initial procedure must address the anterior cranial vault. Although both anterior and posterior portions of the cranium can be repaired during the same procedure, usually one is chosen as the site of primary repair, depending upon which is most severely affected. For hypertelorism and orbital hypoplasia, an orbital advancement is necessary. As mentioned above, significant facial surgery such as a midface advancement is delayed until later in childhood, when the facial bones are more robust and less fragile. The types of complications arising from craniofacial procedures are similar to those encountered with surgery for nonsyndromic craniosynostosis, although blood loss, the risk of dural laceration, and upper airway obstruction probably occur at a higher rate.

Table 4. Classification of encephaloceles

Location Type


Anterior Sincipital

Nasofrontal Nasoethmoidal Naso-orbital Frontoethmoidal

Basal Sphenopharyngeal Spheno-orbital Sphenomaxillary Sphenoethmoidal

Posterior Occipital





The encephalocele is defined by the bones it emerges between;

Sincipital encephaloceles often present with visible mass or an effect on facial growth;

Anterior encephaloceles are more common in certain Asian populations

Basal encephaloceles may not be apparent on physical examination

Encephalocele often affects the location of the torcula; Varying degrees of cerebellar tissue are located within the sac; More common in Caucasians

Craniofacial Clefts and Skull-Base Anomalies


Clefts or microsomias can affect the central face from the maxillary bone to the frontal bone and may result in defects of variable size in the cranial base. Brain or meningeal herniation can cause a progressive deformation of the bony structures at the skull base. This can manifest as an encephalocele protruding into the nose, mouth, or orbit (Table 4). These entities can be diagnosed a physical exam when they are visible or when there are associated cutaneous markers such as midline dimples from the tip of the nose to the forehead. Imaging studies should include a CT scan of the bone (Fig. 9) and an MRI scan to define the neural structures. Most encephaloceles

Figure 9. A coronal CT scan image of a child with a naso-frontal encephalocele. There is protrusion of gliotic brain tissue through the defect in the bone in the floor of the frontal fossa into the nasopharynx.

are covered by normal skin and do not require urgent repair. Some basal encephaloceles, however, can erode through an attenuated dura, leading to a CSF leak and a higher risk of meningitis. Involvement of the pituitary stalk or structures around the sella may produce an endocrinopathy. Herniated brain tissue can cause blindness from compression of the optic nerve. Poorer outcome is associated with increased amount of brain material within the sac and with the presence of hydrocephalus.


Lesions with exposed neural tissue or an obvious CSF leak should be repaired urgently. Treatment of lesions with normal skin coverage can be deferred until a later time for definitive repair. As with craniofacial syndromes, staged repair maybe necessary for anterior encephaloceles with significant facial remodeling and distortion. Surgical repair involves defining the margins of the normal anatomical structures, isolating the transition from normal to dysplastic brain tissue within the sac, truncating this tissue, and performing a watertight dural closure. For posterior encephaloceles in particular, the location of the dural venous sinuses must be determined preoperatively to prevent accidental entry and major blood loss. MRI and CT venography are ideal methods for defining the anatomic relationship between the superior sagittal sinus and torcula, and the dural defect and encephalocele sac. The subsequent reconstruction of the bone may require bone grafts with autologous bone or synthetic material. If hydrocephalus is present, the only way to prevent a CSF leak may be to insert a VP shunt.

Craniofacial Tumors

Benign congenital tumors of the skull base include dermoid tumors, teratomas and hemangiomas. The clinical presentation in infancy includes facial asymmetry, a visible or palpable mass in the nose or mouth, or a cutaneous marker such as a deep dimple in the midline from the tip of the nose to the anterior fontanelle. Congenital tumors may occasionally present after birth as a facial mass, CSF leakage, or meningitis. Detailed imaging studies are mandatory and should include pre- and postcontrast MRI scans and high resolution CT scans of the skull base. Lesions involving the sella and sphenoid bones may require catheter angiography to determine if compression or invasion of the carotid arteries is present. Treatment of these tumors must be individualized depending upon the location and size of the mass, the age of the patient and the ultimate pathology of the lesion. Surgery for benign, anterior skull-base tumors requires a wide exposure to facilitate complete resection and subsequent reconstruction of the dura, cranial base and facial bones. This often requires bifrontal craniotomy in combination with transfacial, transnasal, or transoral approaches.

Malignant tumors of the orbit and cranial base pose significantly more complex technical problems than benign tumors. These tumors include soft tissue sarcomas or sarcomas of the anterior skull base. Malignant teratoma or other germ cell tumors may also occur in this area. The primary goals of surgery for malignant craniofacial

tumors are to obtain adequate tissue for diagnosis and then facilitate optimal multi-modality therapy designed to achieve long-term survival. This may include an attempt at gross total resection with clear margins, followed by adjunctive therapy such as chemotherapy or radiation therapy. For tumors at locations that render them inoperable, biopsy, followed by primary treatment with adjunctive therapy, is an acceptable alternative. Of course, as with any malignant tumor that is not surgically curable, care must be taken to avoid causing deficits to or destruction of neural tissue or important structures at the skull base.

Craniofacial Trauma

Preoperative Evaluation

Craniofacial trauma includes any fractures of the frontal bone that involve the frontal sinus, the orbit and its contents, or the facial structures. These are difficult injuries to treat, particularly when associated with brain injury or disruption of the CSF barrier. Reconstruction is complicated and normal function of the damaged structures in the orbit or skull base may be impossible to restore. Because of the structure of the nasal sinuses, force applied to the face and head from the anterior position may often be absorbed by the facial structures and sinus structures, thereby reducing the likelihood of a severe intracranial injury. Associated injuries to consider include laceration or dissection of the carotid arteries, orbital fractures with entrapment of extraocular muscles, cranial-nerve injuries and delayed upper-airway obstruction.

Initial management should follow the standard resuscitation protocol for all trauma patients. Particular attention should be paid to securing the upper airway. A tracheostomy is usually not necessary, although an extensive facial injury with significant soft-tissue swelling may require a tracheostomy in order to complete the surgical repair. The scalp and face are richly supplied by multiple arteries, and hemodynamically significant blood loss can occur from craniofacial injuries. Nasal catheters should be avoided since they may follow fractures in the anterior skull base into the intracranial space. All intubations, whether endotracheal or gastric, should be performed through the mouth under direct vision. Associated brain injury should be managed in parallel with facial and systemic injuries (see Chapter 3). Temporary hemostasis can almost always be obtained if an urgent surgical procedure is required prior to definitive management of the facial injury. Initial imaging studies of patients with craniofacial trauma should include a plain CT scan of the head as well as a high-resolution craniofacial CT scan with thin cuts through orbits and other affected facial structures. Open facial fractures should be treated with broad antibiotic coverage, such as a 3-antibiotic cocktail of nacillin, ceftriaxone and metronidazole given over several days. A delay in surgical treatment is also indicated in the event of ocular blindness. This should be treated with steroids or, if compression of the optic nerve can be demonstrated conclusively, by decompression of the optic nerve.


Techniques for the treatment of craniofacial fractures are similar to those for elective procedures. A bicoronal skin incision with retraction of the forehead and facial skin down to the mid-orbit area allows excellent access to the cranial vault and upper face and orbit. Additional incisions through the mouth or through the face can be used as necessary to obtain a wider exposure. Open and grossly contaminated wounds should be debrided aggressively and washed thoroughly. Rigid fixation should be used to promote fusion of the bone and prevent infection. In the postoperative period, specific issues to consider include airway protection, particularly for patients who are placed in intermaxillary fixation, routine neurological and visual examinations, and evaluation of endocrine function for anterior skull-base injuries. Post-traumatic CSF leaks are usually treated conservatively with lumbar drainage, although clear structural defects in the anterior fossa floor seen on CT scans almost always require a surgical procedure to repair.

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