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Surgical correction of scaphocephaly: experiences with a new procedure and follow-up investigations
Journal of Cranio-Maxillofacial Surgery (2001) 29, 33–38 # 2001 European Association for Cranio-Maxillofacial Surgery doi:10.1054/jcms.2000.0182, available online at http://www.idealibrary.com on
Surgical correction of scaphocephaly: experiences with a new procedure and follow-up investigations Petros Christophis,1 Thies Hendrik Ju¨nger,2 Hans-Peter Howaldt2 1
Department of Neurosurgery (Head: Prof. Dr. D.-K. Bo¨ker); 2Department of Maxillofacial and Facial Plastic Surgery (Head: Prof. Dr. Dr. H.-P. Howaldt), Medical School, Justus Liebig-University Giessen, Giessen, Germany SUMMARY. Introduction: Simple resection of the sagittal suture and the use of alloplastic material or extensive skull resections have long been proven to be unsatisfactory in the treatment of sagittal synostosis. In contrast to these experiences, the immediate correction of skull shape seems to yield the best results without significant morbidity. Patients: Thirty-six scaphocephalic infants with an average age of 6.5 (3.5–14) months underwent operation by our craniofacial team since 1994. Methods: Wide resection of the sagittal suture was used in combination with a bone-strip resection along the coronal and lambdoid sutures. Occasionally partial resection and reshaping of the frontal or occipital bone was necessary to correct an extremely bulging skull. The cranial growth and shape was monitored by anthropometric skull measurements in the last 20 patients. Results: Except in two cases, in which the dura mater was minimally injured intraoperatively, no complications occurred in any patient. Craniofacial oedema always occurred but disappeared after 72 h. The immediate correction of the skull shape was successful in all cases and was completed within 6 months postoperatively. There was no iatrogenic bone defect one year after surgery. Postoperative skull shape and growth was normal. Conclusion: These procedures seem to be effective in the treatment of scaphocephalus. Further normalization of skull shape is achieved by unrestricted postoperative brain growth. # 2001 European Association for Cranio-Maxillofacial Surgery
INTRODUCTION
MATERIAL AND METHODS
The aesthetic result as well as the cerebral function following decompression surgery in cases with craniosynostosis are dependent on the timing of surgical treatment. The technical ease of the operation and the quality of the results seem to be inversely proportional to the age of the child at surgery (Greene & Winston, 1988; Rodi et al., 1993, Ocampo & Persing, 1994; Esparza et al., 1996; Friede et al., 1996). On the other hand early reossification in the first weeks and months of life endangers the result and may make reoperation necessary (Norwood et al., 1974, Persing et al., 1981). The success of the surgical treatment is also dependent on the extent of decompression (Olds et al., 1986; Czorny et al., 1987; Jimenez & Barone, 1998). Lead by these considerations and the knowledge that growth of brain and skull is greatest in the first 6 months of life (Copoletta & Wolbach, 1933), we chose an age of between 3 months and 1 year for the surgical treatment of scaphocephaly. This treatment includes wide resection of the synostotic sagittal suture and bilateral temporo-parietal decompression by additional resection of bone strips bilaterally posterior to the coronal and anterior to the lambdoid suture. Basically the additional resection must begin at the midline and end 1–2 cm beyond the temporal suture. This procedure attempts not only to correct the shape of the skull, but also to facilitate growth (and thus maturation) of the brain.
Since 1994, 36 children with synostosis of the sagittal suture were treated surgically in our hospital. The average age of the patients was 6.5 months (3.5–14 months) with a majority of male patients (n ¼ 26). Preoperative radiographs (anterior and lateral view) and cranial computerized tomography (CCT) were taken for all patients. The CCT data of the most recently treated children (n ¼ 27) allowed 3-D reconstruction. In the first 20 patients CT scans were repeated 1 year postoperatively to monitor changes in skull morphology and brain growth. With increasing experience, we no longer perform CT scans during follow-up, thus reducing radiation dose. As a noninvasive procedure for comparison, measurements of skull dimensions (anthropometry) were taken preoperatively and postoperatively (after 4–6 weeks, 6 months, 1 year and 2 years) in the last 20 children. In eight children the follow-up time exceeded 3 years. The following parameters were determined: 1. Measurement of the maximum length and maximum width of skull. 2. The distances tragus to tragus and nasion to tragus representing width of the middle and length of the anterior skull base, respectively. 3. Maximum horizontal head circumference and circumference from ear to ear (upper ear base), as well as circumference from nasion to inion (occipital protuberance) as a representative 33
34 Journal of Cranio-Maxillofacial Surgery
measure of the spherical dimensions of the skull vault. The patients were distributed into three groups. The first (1) consisted of children aged 3 to 5 months, the second (2) included children between 5 and 7 months of age, and the third group (3) was composed of children over 7 months of age. The data were compared with normal values (Farkas, 1994). In addition quotients (indices) were created indicating the changes of skull dimensions (Table 1). Surgical procedures (Fig. 1) The children were operated in supine position with anteflexion of the head using a small gel pillow. After shaving and disinfection a solution of xylocain 1% and epinephrine (1 : 200.000) was infiltrated prior to the incision. A bicoronal skin incision was performed supraperiostally approximately 2 cm behind the coronal suture. Dissection was performed supraperiostally in children older than 1 year to maintain full reossification potential of the periosteum. The scalp was reflected beyond the coronal and lambdoidal sutures after dissection in the galeal layer to reduce operative blood loss. In cases in which correction of a frontal or occipital bulge was necessary, the scalp dissection was extended to the glabella anteriorly or to the suboccipital region posteriorly. The extradural space was reached via bone dissection in the region of the open fontanelle or by paramedian burr holes bilaterally. At first a sagittal bone strip resection was made with a torque craniotome 2 cm parasagittally to the midline. In general all bone resections were made in strip form after bipolar electrocoagulation of the periosteum, which was not dissected from the bone. Thus, blood loss could be reduced and simultaneously the matrix for early reossification was reduced in the area of resection. As a second step the bone resection was extended bilaterally in the direction of the skull base, anteriorly 0.5 cm dorsal to the coronal and posteriorly 0.5 cm anterior to the lambdoid suture. The resected area was 1–1.5 cm wide. The caudal end of these bone defects reached 0.5–1 cm beyond the temporal suture. In all children this strip craniectomy led intraoperatively to a clearly noticeable widening of the skull, a small decrease of its length and a definite lowering of its height as soon as the dura mater was dissected under the remaining parieto-temporal bone Table 1 – Indices used for comparison of craniometric data Indices
Relations
Cephalic index (CI) Anterior skull base index (ABI) Spherical cephalic index (SCI)
max. width/max. length nasion-tragion distance/ tragion-tragion distance ear-ear circumference/ max. horizontal circumference
Fig. 1 – Correction of sagittal synostosis: after supraperiosteal scalp dissection the remaining galea-periosteal layers are electrocoagulated and split in strip form in the skull area to be resected. This is followed by a sagittal bone strip resection, extended downwards bilaterally a short distance (3–5 mm) dorsally to the coronal and anteriorly to the lambdoid sutures.
wings. The resulting incongruency between dural and bone surfaces was corrected by remodelling the bone with a bone moulding Tessier forceps. In cases of an abnormal frontal or occipital bulge (n ¼ 17) these were corrected using radial wedge resection and suture fixation followed by remodelling of the bone (Fig. 2). Haemostasis and placement of subgaleal drainage was followed by wound closure. RESULTS The average operation time was 2.5 (2–3.5) h. Postoperatively all children were monitored in the intensive care unit for one day. The intra- and postoperative blood substitution was between 20 and 150 ml erythrocyte concentrate (group I: 72 ml, group II: 82 ml, group III: 130 ml; mean 100 ml). In many cases a transfusion was not absolutely necessary, but was given when the initial haemoglobin concentration was low. In the immediate postoperative phase analgesics were applied routinely. Subcutaneous drains were removed on the second postoperative day. The perioperative swelling of the scalp and face reached a maximum on the second postoperative
Surgical correction of scaphocephaly 35
DISCUSSION
Fig. 2 – Changing skull morphology following correction of scaphocephaly demonstrated in three dimensions (black arrows).
day and was markedly diminished on the third day. The parents were very pleased and thankful upon recognizing the result of the correction (Figs 3A–F). All postoperative craniometric data confirmed the intraoperative impression of achieving an immediate correction, as well as the expected normalization of further skull growth (Table 2). The surgery led to an immediate increase of width and reduction of skull vault length with length and width of the skull base remaining unchanged (Table 3). The maximum skull circumference was also altered slightly. Furthermore we observed, that harmonization of the vault without any irregularities was not achieved in some patients of group III. This especially affected the older children of this group. Case report Postoperative changes of the Cephalic Index (CI) can be demonstrated in particular by a female patient with scaphocephaly and her non-affected twin sister (Fig. 4). The patient was operated at 4.3 months of age. Both were anthropometrically investigated at identical follow-up intervals. The results show, that the postoperative CIs of the operated twin tend towards normal, while the CIs of the non-affected twin are approximately normal and do not change significantly during growth.
Simple strip craniectomies of the synostotic sagittal suture in scaphocephaly, extensive skull resections and the use of alloplastic material to prevent early reossification are ineffective (Olds et al., 1986; Greene & Winston, 1988; Ocampo & Persing, 1994; Esparza et al., 1996; Friede et al., 1996). Intraoperative use of chemicals (Zenker’s fluid) to prevent reossification is dangerous (McComb et al., 1981). In contrast to this, immediate correction of the skull shape yielded the better results. The ‘pi’ technique (Jane et al., 1978) and its variations (Vollmer et al., 1984; Ocampo & Persing, 1994) were frequently used, but they risk the transient danger of decreased brain perfusion via a possible increase of intracranial pressure (Chadduck et al., 1992). Some authors (Czorny et al., 1987; Greene & Winston, 1988; Esparza et al., 1996, Jimenez & Barone, 1998) favoured surgery in infants a few weeks old and usually prefer a ‘large opening’ of the skull. Consecutive widening of the brain seems to have a decisive influence on remodelling and further growth of the skull. All these concepts, in spite of some good results, are apparently not universally applicable for patients of all ages and for all types of scaphocephaly. As postnatal growth of the skull is fastest within the first 3–6 months of life (Copoletta & Wolbach, 1933; Hassler & Zentner, 1990), the form of the cranial vault may be determined by the volume and growth of the brain. Furthermore it is known that reossification of the skull is most likely in the first year of life (Norwood et al., 1974; Persing et al., 1981). Based on this it seems logical that the surgical aim should not only be to correct the skull shape, but also to facilitate skull moulding by brain growth. Surgery should not only convert a ‘synostotic’ to a ‘non-synostotic’ suture, but should also enable correction of the malformation and prevent possible brain damage, which can result from inhibition of brain perfusion in patients with synostosis (Sen et al., 1995). Consequently operative treatment should be undertaken at an earliest possible age but not in the first 2–3 months, since at this early age surgery may be ineffective due to early reossification. This reossification can proceed from all tissue layers and can be only partially controlled. Since the operative treatment of scaphocephaly is an elective procedure the infant should be at a developmental age allowing intervention. In this respect some authors described endoscopic operative methods for infants, successfully applied in the first weeks of life (Jimenez & Barone, 1998), combined with external orthesis treatment to influence the direction and form of further skull growth. Nevertheless, long-term results are not known yet and a representative number of patients have not yet been reported upon. Besides the technical advantages of an operation in the first 6 months (soft and thin skull, virtually non haematopoetic) recent reports (Rodi et al., 1993; Ocampo & Persing, 1994; Thauvoy et al., 1995; Friede et al., 1996; Virtanen et al., 1999) and our own findings show that the best results are obtained when
36 Journal of Cranio-Maxillofacial Surgery
Fig. 3 – (A–F) Aesthetic result of surgical correction of a scaphocephalic boy before (A+B, 5 months of age), 6 weeks (C+D), and 2 years (E+F) postoperatively.
Surgical correction of scaphocephaly 37 Table 2 – Changes of Cephalic Indices in groups of different ages following correction of scaphocephaly. n ¼ number of patients, CIpr ¼ Cephalic Index prior to surgery, CI12 ¼ Cephalic Index 12 months postoperatively Group
n
Age (months)
Average CIpr
Average CI12
CI changes (%)
I II III Total
5 8 7 20
3.5–5 5–7 7–14 3.5–14
0.653 0.668 0.674 0.666
0.758 0.763 0.762 0.761
+13.8 +14.2 +13.0 +13.7
Table 3 – Changes of Anterior Base Indices (same groups as for Table 2) following surgical correction of scaphocephaly. n ¼ number of patients, ABIpr ¼ Anterior Base Index prior to surgery, ABI12 ¼ Anterior Base Index 12 months postoperatively Group
n
Age (months)
Average ABIpr
Average ABI12
ABI changes (%)
I II III Total
5 8 7 20
3.5–5 5–7 7–14 3.5–14
0.820 0.930 0.858 0.877
0.841 0.890 0.868 0.870
+2.5 74.3 +1.2 70.8
Fig. 4 – Pre- and postoperative Cephalic Index of a 4.3 months old female patient (– – &– –) with scaphocephaly and her non-affected twin sister (—&—).
surgical reconfiguration of the skull vault is completely (‘immediate correction’). Furthermore the necessity of plate or wire fixation in older patients implies secondary surgery (Breugem & van R Zeeman, 1999). However, it is also essential that surgery must be planned individually according to skull deformity and the age of the patient. Alteration of skull proportions is documented best by the Cephalic Index (CI ¼ maximum width : maximum length), which on average became normal postoperatively when compared with the data published by Farkas (1994): average CI for children within the first year of life beeing between 0.747 (girls) and 0.757 (boys). This index was abnormally low (average CIpr ¼ 0.666) before the operation, was already normalized at the first postoperative measurement (average CIpo ¼ 0.753) and was slightly higher than normal (average CI6 ¼ 0.765) 6 months postoperatively and stayed nearly unchanged for up to a year with normal skull growth. The postoperative increase of the CI after 1 year (mean CI12 ¼ 0.761) was 13.7% on average and there were no significant differences between the three groups.
The ‘immediate correction’ of the skull vault should not only realize a temporary aesthetic improvement of the shape, but should also lead to an improvement in growth of the vault. The concept described in this paper represents a complementing or modification of many of the existing methods, which only satisfy some of the prerequisites. A very similar concept has been successfully practised in the past by Stein & Shut (1977). The advantages of the present method are clear: 1. immediate correction, which is complete if surgery was done in the first 6 months of life, 2. sparing growth of the normal sutures, 3. no transient diminuition of the skull volume, 4. favouring physiological growth of the skull by decompression and enabling volume expansion and normal brain growth until reossification, 5. intraoperative blood loss is low especially in patients younger than 7 months, 6. controlled reossification combined with sufficient protection of the brain against
38 Journal of Cranio-Maxillofacial Surgery
mechanical injury by retaining bone fragments, which are connected to the skull base.
CONCLUSION The advantages of the method described and the results achieved demonstrate that it is worthwhile and is accompanied by a very low and transient morbidity. Differences in the postoperative Cephalic Index within the three groups are statistically not significant. However, in agreement with the results of Maggi et al. (1998), our impression is, that the long term results of patients treated after the first half year of life only show a partial correction of the anomaly. Despite this the method may be applied up to the fourteenth month as long as the limited reossification tendency is taken into account and the intended correction of the skull can be achieved. However, it remains to be discussed whether the required aesthetic ‘normalization’ or ‘correction’ of skull form is to be understood as ‘rounding’ of the skull. Whether this is physiologically or genetically normal has to be discussed as well. It therefore appears to be much more important to enable uninhibited and physiological brain growth, rather than just to achieve an aesthetically excellent skull form. References Breugem CC, van R Zeeman BJ: Retrospective study of nonsyndromic craniosynostosis treated over a 10-year period. J Craniofac Surg 10: 140–143, 1999 Chadduck WM, Chadduck JB, Boop FA: The subarachnoidal spaces in craniosynostosis. Neurosurg 30: 867–871, 1992 Copoletta JM, Wolbach SB: Body length and organ weights of infants and children. A study of the body length and normal weights of the more important vital organs of the body between birth and twelve years of age. Am J Pathol 9: 55–75, 1933 Czorny A, Chocron S, Forlodou P, Tisserant D, Striker M, Montaut J: Scaphocephalies. Traitement et complications – propos de 115 cas. Neurochir (France) 33: 190–195, 1987 Esparza J, Cordobes F, Munoz MJ et al: Tratamiento de la craneosinostosis sagital (escaphocefalia), por medio de la correction quirurgica inmediata. Ann Esp Pediatr 45: 143–148, 1996 Farkas LG: Anthropometry of the head and neck. Raven Press, New York, 2nd ed, Appendix A, 241–270, 1994 Friede H, Lauritzen C, Figueroa AA: Roentgenencephalometric follow-up after early osteotomies in patients with scaphocephaly. J Craniofac Surg 7: 96–101, 1996
Greene CS Jr, Winston KR: Treatment of scaphocephaly with sagittal craniectomy and biparietal morcellation. Neurosurg 23: 196–201, 1988 Hassler W, Zentner J: Radical osteoclastic craniectomy in sagittal synostosis. Neurosurg 27: 539–543, 1990 Jane JA, Edgerton MT, Futrell JW, Park TS: Immediate correction of sagittal synostosis. J Neurosurg 49: 705–710, 1978 Jimenez DF, Barone, CM: Endoscopic craniectomy for early surgical correction of sagittal craniosynostosis. J Neurosurg 88: 77–81, 1998 Maggi G, Aliberti F, Pittore L: Occipital remolding for correction of scaphocephaly in the young infant. Technical note. J Neurosurg Sci 42: 119–122, 1998 McComb JG, Withers GL, Davis RL: Cortical damage from Zenker’s solution applied to the dura mater. Neurosurg 8: 68–71, 1981 Norwood CW, Alexander E, Davis CH, Kelly DL: Recurrent and multiple suture closures after craniectomy for craniosynostosis. J Neurosurg 41: 715–719, 1974 Ocampo RV, Persing JA: Sagittal synostosis. Clinics in plastic surgery. J Craniofac Surg 21: 563–574, 1994 Olds MV, Storrs B, Walker ML: Surgical treatment of sagittal synostosis. Neurosurg 18: 345–347, 1986 Persing J, Babler W, Winn HR, Jane J, Rodeheaver G: Age as a critical factor in the success of surgical correction of scaphocephaly. J Neurosurg 54: 601–606, 1981 Rodi R, Vaandrager JM, Gilbert PM, van der Meulen JCH: Reshaping of the skull in the early surgical correction of scaphocephaly. J Cranio Max-Fac Surg 2: 226–233, 1993 Sen A, Dougal P, Padhy AK et al: Technetium-99-HMPAO SPECT cerebral blood flow study in children with craniosynostosis. J Nucl Med 36: 394–398, 1995 Stein SC, Shut L: Management of scaphocephaly. Surg Neurol 7: 153–159, 1977 Thauvoy C, Scholtes JL, Moulin D, Reychler H: Craniostenoses et dysmorphies cranio-faciales. Acta Neurol Belg 95: 147–163, 1995 Virtanen R, Korhonen T, Fagerholm J, Viljanto J: Neurocognitive sequelae of scaphocephaly. Pediatrics 103: 791–795, 1999 Vollmer DG, Jane JA, Park TS, Persing GA: Variants of sagittal synostosis. Strategies for surgical correction. J Neurosurg 6: 557–562, 1984
Priv.-Doz. Dr. Petros Christophis MD, PhD Department of Neurosurgery Medical School Justus Liebig-University Giessen Klinikstraße 29 D-35385 Giessen Germany Tel: +49 641 99 45500 Fax: +49 641 99 45529 or 99/45549 E-mail: [email protected] Paper received 31 January 2000 Accepted 5 December 2000
Surgical correction of scaphocephaly: experiences with a new procedure and follow-up investigations Petros Christophis,1 Thies Hendrik Ju¨nger,2 Hans-Peter Howaldt2 1
Department of Neurosurgery (Head: Prof. Dr. D.-K. Bo¨ker); 2Department of Maxillofacial and Facial Plastic Surgery (Head: Prof. Dr. Dr. H.-P. Howaldt), Medical School, Justus Liebig-University Giessen, Giessen, Germany SUMMARY. Introduction: Simple resection of the sagittal suture and the use of alloplastic material or extensive skull resections have long been proven to be unsatisfactory in the treatment of sagittal synostosis. In contrast to these experiences, the immediate correction of skull shape seems to yield the best results without significant morbidity. Patients: Thirty-six scaphocephalic infants with an average age of 6.5 (3.5–14) months underwent operation by our craniofacial team since 1994. Methods: Wide resection of the sagittal suture was used in combination with a bone-strip resection along the coronal and lambdoid sutures. Occasionally partial resection and reshaping of the frontal or occipital bone was necessary to correct an extremely bulging skull. The cranial growth and shape was monitored by anthropometric skull measurements in the last 20 patients. Results: Except in two cases, in which the dura mater was minimally injured intraoperatively, no complications occurred in any patient. Craniofacial oedema always occurred but disappeared after 72 h. The immediate correction of the skull shape was successful in all cases and was completed within 6 months postoperatively. There was no iatrogenic bone defect one year after surgery. Postoperative skull shape and growth was normal. Conclusion: These procedures seem to be effective in the treatment of scaphocephalus. Further normalization of skull shape is achieved by unrestricted postoperative brain growth. # 2001 European Association for Cranio-Maxillofacial Surgery
INTRODUCTION
MATERIAL AND METHODS
The aesthetic result as well as the cerebral function following decompression surgery in cases with craniosynostosis are dependent on the timing of surgical treatment. The technical ease of the operation and the quality of the results seem to be inversely proportional to the age of the child at surgery (Greene & Winston, 1988; Rodi et al., 1993, Ocampo & Persing, 1994; Esparza et al., 1996; Friede et al., 1996). On the other hand early reossification in the first weeks and months of life endangers the result and may make reoperation necessary (Norwood et al., 1974, Persing et al., 1981). The success of the surgical treatment is also dependent on the extent of decompression (Olds et al., 1986; Czorny et al., 1987; Jimenez & Barone, 1998). Lead by these considerations and the knowledge that growth of brain and skull is greatest in the first 6 months of life (Copoletta & Wolbach, 1933), we chose an age of between 3 months and 1 year for the surgical treatment of scaphocephaly. This treatment includes wide resection of the synostotic sagittal suture and bilateral temporo-parietal decompression by additional resection of bone strips bilaterally posterior to the coronal and anterior to the lambdoid suture. Basically the additional resection must begin at the midline and end 1–2 cm beyond the temporal suture. This procedure attempts not only to correct the shape of the skull, but also to facilitate growth (and thus maturation) of the brain.
Since 1994, 36 children with synostosis of the sagittal suture were treated surgically in our hospital. The average age of the patients was 6.5 months (3.5–14 months) with a majority of male patients (n ¼ 26). Preoperative radiographs (anterior and lateral view) and cranial computerized tomography (CCT) were taken for all patients. The CCT data of the most recently treated children (n ¼ 27) allowed 3-D reconstruction. In the first 20 patients CT scans were repeated 1 year postoperatively to monitor changes in skull morphology and brain growth. With increasing experience, we no longer perform CT scans during follow-up, thus reducing radiation dose. As a noninvasive procedure for comparison, measurements of skull dimensions (anthropometry) were taken preoperatively and postoperatively (after 4–6 weeks, 6 months, 1 year and 2 years) in the last 20 children. In eight children the follow-up time exceeded 3 years. The following parameters were determined: 1. Measurement of the maximum length and maximum width of skull. 2. The distances tragus to tragus and nasion to tragus representing width of the middle and length of the anterior skull base, respectively. 3. Maximum horizontal head circumference and circumference from ear to ear (upper ear base), as well as circumference from nasion to inion (occipital protuberance) as a representative 33
34 Journal of Cranio-Maxillofacial Surgery
measure of the spherical dimensions of the skull vault. The patients were distributed into three groups. The first (1) consisted of children aged 3 to 5 months, the second (2) included children between 5 and 7 months of age, and the third group (3) was composed of children over 7 months of age. The data were compared with normal values (Farkas, 1994). In addition quotients (indices) were created indicating the changes of skull dimensions (Table 1). Surgical procedures (Fig. 1) The children were operated in supine position with anteflexion of the head using a small gel pillow. After shaving and disinfection a solution of xylocain 1% and epinephrine (1 : 200.000) was infiltrated prior to the incision. A bicoronal skin incision was performed supraperiostally approximately 2 cm behind the coronal suture. Dissection was performed supraperiostally in children older than 1 year to maintain full reossification potential of the periosteum. The scalp was reflected beyond the coronal and lambdoidal sutures after dissection in the galeal layer to reduce operative blood loss. In cases in which correction of a frontal or occipital bulge was necessary, the scalp dissection was extended to the glabella anteriorly or to the suboccipital region posteriorly. The extradural space was reached via bone dissection in the region of the open fontanelle or by paramedian burr holes bilaterally. At first a sagittal bone strip resection was made with a torque craniotome 2 cm parasagittally to the midline. In general all bone resections were made in strip form after bipolar electrocoagulation of the periosteum, which was not dissected from the bone. Thus, blood loss could be reduced and simultaneously the matrix for early reossification was reduced in the area of resection. As a second step the bone resection was extended bilaterally in the direction of the skull base, anteriorly 0.5 cm dorsal to the coronal and posteriorly 0.5 cm anterior to the lambdoid suture. The resected area was 1–1.5 cm wide. The caudal end of these bone defects reached 0.5–1 cm beyond the temporal suture. In all children this strip craniectomy led intraoperatively to a clearly noticeable widening of the skull, a small decrease of its length and a definite lowering of its height as soon as the dura mater was dissected under the remaining parieto-temporal bone Table 1 – Indices used for comparison of craniometric data Indices
Relations
Cephalic index (CI) Anterior skull base index (ABI) Spherical cephalic index (SCI)
max. width/max. length nasion-tragion distance/ tragion-tragion distance ear-ear circumference/ max. horizontal circumference
Fig. 1 – Correction of sagittal synostosis: after supraperiosteal scalp dissection the remaining galea-periosteal layers are electrocoagulated and split in strip form in the skull area to be resected. This is followed by a sagittal bone strip resection, extended downwards bilaterally a short distance (3–5 mm) dorsally to the coronal and anteriorly to the lambdoid sutures.
wings. The resulting incongruency between dural and bone surfaces was corrected by remodelling the bone with a bone moulding Tessier forceps. In cases of an abnormal frontal or occipital bulge (n ¼ 17) these were corrected using radial wedge resection and suture fixation followed by remodelling of the bone (Fig. 2). Haemostasis and placement of subgaleal drainage was followed by wound closure. RESULTS The average operation time was 2.5 (2–3.5) h. Postoperatively all children were monitored in the intensive care unit for one day. The intra- and postoperative blood substitution was between 20 and 150 ml erythrocyte concentrate (group I: 72 ml, group II: 82 ml, group III: 130 ml; mean 100 ml). In many cases a transfusion was not absolutely necessary, but was given when the initial haemoglobin concentration was low. In the immediate postoperative phase analgesics were applied routinely. Subcutaneous drains were removed on the second postoperative day. The perioperative swelling of the scalp and face reached a maximum on the second postoperative
Surgical correction of scaphocephaly 35
DISCUSSION
Fig. 2 – Changing skull morphology following correction of scaphocephaly demonstrated in three dimensions (black arrows).
day and was markedly diminished on the third day. The parents were very pleased and thankful upon recognizing the result of the correction (Figs 3A–F). All postoperative craniometric data confirmed the intraoperative impression of achieving an immediate correction, as well as the expected normalization of further skull growth (Table 2). The surgery led to an immediate increase of width and reduction of skull vault length with length and width of the skull base remaining unchanged (Table 3). The maximum skull circumference was also altered slightly. Furthermore we observed, that harmonization of the vault without any irregularities was not achieved in some patients of group III. This especially affected the older children of this group. Case report Postoperative changes of the Cephalic Index (CI) can be demonstrated in particular by a female patient with scaphocephaly and her non-affected twin sister (Fig. 4). The patient was operated at 4.3 months of age. Both were anthropometrically investigated at identical follow-up intervals. The results show, that the postoperative CIs of the operated twin tend towards normal, while the CIs of the non-affected twin are approximately normal and do not change significantly during growth.
Simple strip craniectomies of the synostotic sagittal suture in scaphocephaly, extensive skull resections and the use of alloplastic material to prevent early reossification are ineffective (Olds et al., 1986; Greene & Winston, 1988; Ocampo & Persing, 1994; Esparza et al., 1996; Friede et al., 1996). Intraoperative use of chemicals (Zenker’s fluid) to prevent reossification is dangerous (McComb et al., 1981). In contrast to this, immediate correction of the skull shape yielded the better results. The ‘pi’ technique (Jane et al., 1978) and its variations (Vollmer et al., 1984; Ocampo & Persing, 1994) were frequently used, but they risk the transient danger of decreased brain perfusion via a possible increase of intracranial pressure (Chadduck et al., 1992). Some authors (Czorny et al., 1987; Greene & Winston, 1988; Esparza et al., 1996, Jimenez & Barone, 1998) favoured surgery in infants a few weeks old and usually prefer a ‘large opening’ of the skull. Consecutive widening of the brain seems to have a decisive influence on remodelling and further growth of the skull. All these concepts, in spite of some good results, are apparently not universally applicable for patients of all ages and for all types of scaphocephaly. As postnatal growth of the skull is fastest within the first 3–6 months of life (Copoletta & Wolbach, 1933; Hassler & Zentner, 1990), the form of the cranial vault may be determined by the volume and growth of the brain. Furthermore it is known that reossification of the skull is most likely in the first year of life (Norwood et al., 1974; Persing et al., 1981). Based on this it seems logical that the surgical aim should not only be to correct the skull shape, but also to facilitate skull moulding by brain growth. Surgery should not only convert a ‘synostotic’ to a ‘non-synostotic’ suture, but should also enable correction of the malformation and prevent possible brain damage, which can result from inhibition of brain perfusion in patients with synostosis (Sen et al., 1995). Consequently operative treatment should be undertaken at an earliest possible age but not in the first 2–3 months, since at this early age surgery may be ineffective due to early reossification. This reossification can proceed from all tissue layers and can be only partially controlled. Since the operative treatment of scaphocephaly is an elective procedure the infant should be at a developmental age allowing intervention. In this respect some authors described endoscopic operative methods for infants, successfully applied in the first weeks of life (Jimenez & Barone, 1998), combined with external orthesis treatment to influence the direction and form of further skull growth. Nevertheless, long-term results are not known yet and a representative number of patients have not yet been reported upon. Besides the technical advantages of an operation in the first 6 months (soft and thin skull, virtually non haematopoetic) recent reports (Rodi et al., 1993; Ocampo & Persing, 1994; Thauvoy et al., 1995; Friede et al., 1996; Virtanen et al., 1999) and our own findings show that the best results are obtained when
36 Journal of Cranio-Maxillofacial Surgery
Fig. 3 – (A–F) Aesthetic result of surgical correction of a scaphocephalic boy before (A+B, 5 months of age), 6 weeks (C+D), and 2 years (E+F) postoperatively.
Surgical correction of scaphocephaly 37 Table 2 – Changes of Cephalic Indices in groups of different ages following correction of scaphocephaly. n ¼ number of patients, CIpr ¼ Cephalic Index prior to surgery, CI12 ¼ Cephalic Index 12 months postoperatively Group
n
Age (months)
Average CIpr
Average CI12
CI changes (%)
I II III Total
5 8 7 20
3.5–5 5–7 7–14 3.5–14
0.653 0.668 0.674 0.666
0.758 0.763 0.762 0.761
+13.8 +14.2 +13.0 +13.7
Table 3 – Changes of Anterior Base Indices (same groups as for Table 2) following surgical correction of scaphocephaly. n ¼ number of patients, ABIpr ¼ Anterior Base Index prior to surgery, ABI12 ¼ Anterior Base Index 12 months postoperatively Group
n
Age (months)
Average ABIpr
Average ABI12
ABI changes (%)
I II III Total
5 8 7 20
3.5–5 5–7 7–14 3.5–14
0.820 0.930 0.858 0.877
0.841 0.890 0.868 0.870
+2.5 74.3 +1.2 70.8
Fig. 4 – Pre- and postoperative Cephalic Index of a 4.3 months old female patient (– – &– –) with scaphocephaly and her non-affected twin sister (—&—).
surgical reconfiguration of the skull vault is completely (‘immediate correction’). Furthermore the necessity of plate or wire fixation in older patients implies secondary surgery (Breugem & van R Zeeman, 1999). However, it is also essential that surgery must be planned individually according to skull deformity and the age of the patient. Alteration of skull proportions is documented best by the Cephalic Index (CI ¼ maximum width : maximum length), which on average became normal postoperatively when compared with the data published by Farkas (1994): average CI for children within the first year of life beeing between 0.747 (girls) and 0.757 (boys). This index was abnormally low (average CIpr ¼ 0.666) before the operation, was already normalized at the first postoperative measurement (average CIpo ¼ 0.753) and was slightly higher than normal (average CI6 ¼ 0.765) 6 months postoperatively and stayed nearly unchanged for up to a year with normal skull growth. The postoperative increase of the CI after 1 year (mean CI12 ¼ 0.761) was 13.7% on average and there were no significant differences between the three groups.
The ‘immediate correction’ of the skull vault should not only realize a temporary aesthetic improvement of the shape, but should also lead to an improvement in growth of the vault. The concept described in this paper represents a complementing or modification of many of the existing methods, which only satisfy some of the prerequisites. A very similar concept has been successfully practised in the past by Stein & Shut (1977). The advantages of the present method are clear: 1. immediate correction, which is complete if surgery was done in the first 6 months of life, 2. sparing growth of the normal sutures, 3. no transient diminuition of the skull volume, 4. favouring physiological growth of the skull by decompression and enabling volume expansion and normal brain growth until reossification, 5. intraoperative blood loss is low especially in patients younger than 7 months, 6. controlled reossification combined with sufficient protection of the brain against
38 Journal of Cranio-Maxillofacial Surgery
mechanical injury by retaining bone fragments, which are connected to the skull base.
CONCLUSION The advantages of the method described and the results achieved demonstrate that it is worthwhile and is accompanied by a very low and transient morbidity. Differences in the postoperative Cephalic Index within the three groups are statistically not significant. However, in agreement with the results of Maggi et al. (1998), our impression is, that the long term results of patients treated after the first half year of life only show a partial correction of the anomaly. Despite this the method may be applied up to the fourteenth month as long as the limited reossification tendency is taken into account and the intended correction of the skull can be achieved. However, it remains to be discussed whether the required aesthetic ‘normalization’ or ‘correction’ of skull form is to be understood as ‘rounding’ of the skull. Whether this is physiologically or genetically normal has to be discussed as well. It therefore appears to be much more important to enable uninhibited and physiological brain growth, rather than just to achieve an aesthetically excellent skull form. References Breugem CC, van R Zeeman BJ: Retrospective study of nonsyndromic craniosynostosis treated over a 10-year period. J Craniofac Surg 10: 140–143, 1999 Chadduck WM, Chadduck JB, Boop FA: The subarachnoidal spaces in craniosynostosis. Neurosurg 30: 867–871, 1992 Copoletta JM, Wolbach SB: Body length and organ weights of infants and children. A study of the body length and normal weights of the more important vital organs of the body between birth and twelve years of age. Am J Pathol 9: 55–75, 1933 Czorny A, Chocron S, Forlodou P, Tisserant D, Striker M, Montaut J: Scaphocephalies. Traitement et complications – propos de 115 cas. Neurochir (France) 33: 190–195, 1987 Esparza J, Cordobes F, Munoz MJ et al: Tratamiento de la craneosinostosis sagital (escaphocefalia), por medio de la correction quirurgica inmediata. Ann Esp Pediatr 45: 143–148, 1996 Farkas LG: Anthropometry of the head and neck. Raven Press, New York, 2nd ed, Appendix A, 241–270, 1994 Friede H, Lauritzen C, Figueroa AA: Roentgenencephalometric follow-up after early osteotomies in patients with scaphocephaly. J Craniofac Surg 7: 96–101, 1996
Greene CS Jr, Winston KR: Treatment of scaphocephaly with sagittal craniectomy and biparietal morcellation. Neurosurg 23: 196–201, 1988 Hassler W, Zentner J: Radical osteoclastic craniectomy in sagittal synostosis. Neurosurg 27: 539–543, 1990 Jane JA, Edgerton MT, Futrell JW, Park TS: Immediate correction of sagittal synostosis. J Neurosurg 49: 705–710, 1978 Jimenez DF, Barone, CM: Endoscopic craniectomy for early surgical correction of sagittal craniosynostosis. J Neurosurg 88: 77–81, 1998 Maggi G, Aliberti F, Pittore L: Occipital remolding for correction of scaphocephaly in the young infant. Technical note. J Neurosurg Sci 42: 119–122, 1998 McComb JG, Withers GL, Davis RL: Cortical damage from Zenker’s solution applied to the dura mater. Neurosurg 8: 68–71, 1981 Norwood CW, Alexander E, Davis CH, Kelly DL: Recurrent and multiple suture closures after craniectomy for craniosynostosis. J Neurosurg 41: 715–719, 1974 Ocampo RV, Persing JA: Sagittal synostosis. Clinics in plastic surgery. J Craniofac Surg 21: 563–574, 1994 Olds MV, Storrs B, Walker ML: Surgical treatment of sagittal synostosis. Neurosurg 18: 345–347, 1986 Persing J, Babler W, Winn HR, Jane J, Rodeheaver G: Age as a critical factor in the success of surgical correction of scaphocephaly. J Neurosurg 54: 601–606, 1981 Rodi R, Vaandrager JM, Gilbert PM, van der Meulen JCH: Reshaping of the skull in the early surgical correction of scaphocephaly. J Cranio Max-Fac Surg 2: 226–233, 1993 Sen A, Dougal P, Padhy AK et al: Technetium-99-HMPAO SPECT cerebral blood flow study in children with craniosynostosis. J Nucl Med 36: 394–398, 1995 Stein SC, Shut L: Management of scaphocephaly. Surg Neurol 7: 153–159, 1977 Thauvoy C, Scholtes JL, Moulin D, Reychler H: Craniostenoses et dysmorphies cranio-faciales. Acta Neurol Belg 95: 147–163, 1995 Virtanen R, Korhonen T, Fagerholm J, Viljanto J: Neurocognitive sequelae of scaphocephaly. Pediatrics 103: 791–795, 1999 Vollmer DG, Jane JA, Park TS, Persing GA: Variants of sagittal synostosis. Strategies for surgical correction. J Neurosurg 6: 557–562, 1984
Priv.-Doz. Dr. Petros Christophis MD, PhD Department of Neurosurgery Medical School Justus Liebig-University Giessen Klinikstraße 29 D-35385 Giessen Germany Tel: +49 641 99 45500 Fax: +49 641 99 45529 or 99/45549 E-mail: [email protected] Paper received 31 January 2000 Accepted 5 December 2000