The improved management of craniosynostosis has let emerge concomitant anatomical, functional and clinical features that are frequently faced later in life (especially by syndromic patients) and might variably encompass the cranial nerves due to stenosis of bone foramina, abnormal intracranial pressure, or anomalous gene-driven development. Clinical consequences vary according to the affected nerves, the severity and the pathogenesis of nerve involvement but also might depend on early appropriate treatment. Vision, smell and hearing, but also feeding, swallowing and facial mimic or esthesia might be affected with a possible dramatic impact on the overall development of the child and on its quality of life. A systematic literature review regarding cranial nerves involvement in craniosynostosis was performed, including case series and case reports. According to PRISMA criteria, PubMed and Scopus were searched up to February 2025 by two independent reviewers. Relevant English-language case reports and case series were included, while duplicate or aggregated data were excluded. Reference lists were screened, and disagreements were resolved by consensus. Sixty-three papers were considered. Data extracted from the papers were subjected to statistical analysis only for the optic nerve, owing to the paucity of data concerning the other cranial nerves. Optic nerve involvement was reported in 140 patients (44 papers) and included papilledema (69 patients), optic nerve atrophy (69 patients), and optic nerve hypoplasia (5 patients). Visual function was reduced in 65 patients, normal in 9. In sixty-eight patients (49
BACKGROUND:Previous research on communicative outcomes in children treated for nonsyndromic craniosynostosis (NSC) has yielded inconsistent findings, with reported prevalence rates of communicative difficulties varying widely. These discrepancies are attributable to small samples, heterogeneous age groups, and reliance on indirect or non-domain-specific outcome measures. There remains a need for systematic, age-specific screening using validated tools to clarify the nature and prevalence of communicative vulnerabilities in this population. AIMS:The primary aim was to assess guardian-reported communicative abilities in a consecutive cohort of 5-year-old children treated for NSC and compare outcomes with normative data. Secondary aims were to examine whether reported difficulties were predominantly speech-language based or pragmatic, and to explore differences related to NSC subtype and timing of surgery. METHODS AND PROCEDURES:This cross-sectional study included 157 children treated for NSC at a national craniofacial centre in Sweden. Guardians completed the Children's Communication Checklist-2 (CCC-2) as part of routine 5-year follow-up. General Communication Composite (GCC) scores and subscale profiles were analysed and compared with published normative data. Group differences across synostosis type and surgical timing were examined using parametric and non-parametric statistical methods. OUTCOMES AND RESULTS:Eighty-five percent of children scored within the normative range on the GCC. Fifteen percent scored below the clinical cut-off, a proportion not significantly different from the normative sample. Group-level differences were primarily observed in the domains of speech and language, with significantly lower scores in speech and syntax, while pragmatic difficulties were uncommon. No significant differences were found between craniosynostosis subtypes. Earlier surgery was associated with higher GCC scores in children with metopic NSC only. CONCLUSION AND IMPLICATIONS:Most children treated for NSC demonstrate age-appropriate communicative abilities at 5 years of age. However, subtle vulnerabilities in speech and syntax were present in a subset of children. These findings support the use of screening in routine follow-up to identify children who may benefit from further assessment, while suggesting that broad language disorder-like profiles are uncommon in this population. WHAT THIS PAPER ADDS:What is already known on this subject Previous studies report highly variable rates of speech and language difficulties in children treated for nonsyndromic craniosynostosis (NSC), ranging from low to markedly elevated prevalence. What this study adds to the existing knowledge In a large consecutive cohort of 5-year-old children treated for NSC, 85% showed age-appropriate communicative abilities as rated by their guardians and did not differ significantly from normative data. Group-level differences were confined to speech- and language domains (speech and syntax), while pragmatic difficulties were uncommon. Earlier surgery was associated with higher communication scores in children with metopic NSC only. What are the potential or actual clinical implications of this study? Routine screening at follow-up is supported to identify speech- and language vulnerabilities in a minority of children treated for NSC. Broad language disorder-like profiles appear uncommon, suggesting that monitoring of speech and syntax may be more clinically relevant than global language screening alone.
Emissary veins connect intra- and extracranial venous circulation by bridging the dural venous sinuses to the external veins of the skull. Their variable presence and location may have important implications in perioperative blood loss. Clinical observations and previous studies suggest that emissary veins are more frequently present in the glabellar region in patients with metopic synostosis and may serve as a source of bleeding during cranioplasty. This study investigated the presence of emissary veins in the glabellar region in patients with metopic synostosis. We retrospectively analyzed computed tomography scans for the presence of emissary veins in the glabellar region in all consecutive patients who underwent surgery for metopic synostosis or sagittal synostosis (controls) between 2020 and 2022 at the Craniofacial Unit at Sahlgrenska University Hospital. Among 86 patients included in the study (42 with metopic synostosis and 44 with sagittal synostosis), we identified emissary veins in the glabellar region in 90.5% of patients with metopic synostosis as compared with 11.4% of those with sagittal synostosis (p < 0.001). These results suggest that emissary veins in the glabellar region are more frequently present in patients with metopic synostosis relative to age-matched controls with a normal metopic suture, derived from our registry of patients with sagittal synostosis. This anatomical finding may explain the high perioperative blood loss observed during cranioplasty for metopic synostosis.
Surgical treatment of craniosynostosis includes a wide range of techniques. Although a variety of more extensive cranioplasties have been employed to enhance outcomes, efforts to identify less invasive surgical approaches with better results continue. Since the introduction of springs as a tool for craniosynostosis surgery in 1997 at Sahlgrenska University Hospital in Gothenburg, Sweden, several studies have established their utility as an efficient surgical method. Because springs are currently used in the majority of our surgeries addressing craniosynostosis in children, this review summarizes our extensive experience with this method in more than 750 surgeries.
Introduction: Hydrocephalus is more common in patients with craniofacial syndromes (CS) relative to non-syndromic craniosynostosis, and the optimal management is challenging. This study examined the prevalence and treatment outcomes of hydrocephalus among children with CS. Materials and methods: We performed a retrospective review of medical records for all children with established CS and registered in the Gothenburg Craniofacial Registry between 1975 and 2022. This review included analyses of data regarding patient demographics, radiological imaging, hydrocephalus treatment modalities, and shunt revisions. Results: Eligible patients (n = 193) included those with CS, including Pfeiffer (n = 13), Crouzon (n = 57), Apert (n = 49), Muenke (n = 25), and Saethre–Chotzen (n = 49) syndromes. A total of 22 patients (11.4%) presented hydrocephalus requiring treatment [Pfeiffer, n = 8 (61.5%); Crouzon, n = 13 (22.8%); and Apert, n = 1 (2.0%)]. Nineteen (9.8%) patients underwent ventricular shunt insertion, and three (1.6%) underwent endoscopic third ventriculostomy as a first procedure. None of the Muenke or Saethre–Chotzen patients required hydrocephalus treatment. Seventeen (85%) patients with shunts required revision mainly due to shunt obstruction. Pfeiffer patients had the highest risk of both developing hydrocephalus requiring treatment and needing shunt revision (p < 0.001 and p = 0.004, respectively). Approximately 40% of patients with Pfeiffer, Crouzon, or Apert presented ventriculomegaly not requiring treatment. Conclusions: Hydrocephalus requiring treatment is common in Pfeiffer and Crouzon patients but rare in Apert, Muenke, or Saethre–Chotzen syndrome. Shunt treatment is often associated with complications that require revisions, emphasizing the importance of distinguishing non-progressive ventriculomegaly from hydrocephalus requiring treatment.
BACKGROUND:Recent studies show that levels of the brain injury biomarkers glial fibrillary acidic protein (GFAP) and neurofilament light (NfL) are elevated postoperatively in infants undergoing surgery for craniosynostosis. The aim of this study was to investigate the relationship between intraoperative hypotension and blood loss on biomarker levels. METHODS:This retrospective study included all consecutive patients undergoing surgery for metopic synostosis at our institution from January 2019 to September 2020 who were included in a previous trial. We extracted data from the medical record on intraoperative blood pressure, heart rate, and intraoperative blood loss. Pre- and postoperative GFAP and NfL levels were measured in stored blood samples. Hypotension was defined as the area under the curve (AUC) of mean arterial blood pressure (MAP) at 4 threshold levels (35, 40, 45, and 50 mm Hg, respectively). This AUC and intraoperative blood loss were used to identify correlations with postoperative changes in baseline GFAP and NfL levels. RESULTS:A total of 20 patients [age: 190±65 d (mean±SD); and weight: 8.0±1.0 kg] undergoing an open cranial vault procedure for metopic synostosis repair were included. Intraoperative blood loss was 27±11 mL/kg, and we did not identify significant association between plasma NfL or GFAP level and any MAP threshold (NfL AUC40 rs =0.08, AUC45 rs =0.15, AUC50 rs =0.30. GFAP AUC40 rs =-0.17, AUC45 rs =0.01, AUC50 rs =-0.06) or blood loss parameter [NfL rs =0.26, GFAP rs =-0.15]. CONCLUSION:We did not identify a relationship between MAP, blood loss, and markers of brain injury. Our findings suggest that other factors (eg, mechanical manipulation) may explain the observed elevations in brain injury biomarkers after craniosynostosis surgery. This study is limited by its sample size and further investigation is needed.
Background:Sagittal synostosis is the most common type of premature suture closure, and many surgical techniques are used to correct scaphocephalic skull shape. Given the rarity of direct comparisons of different surgical techniques for correcting craniosynostosis, this study compared outcomes of craniotomy combined with springs and H-craniectomy for nonsyndromic sagittal synostosis.Methods:Comparisons were performed using available preoperative and postoperative imaging and follow-up data from the 2 craniofacial national referral centers in Sweden, which perform 2 different surgical techniques: craniotomy combined with springs and H-craniectomy (the Renier technique). The study included 23 pairs of patients matched for sex, preoperative cephalic index, and age. Cephalic index, total intracranial volume (ICV), and partial ICV were measured before surgery and at 3 years of age, with volume measurements compared against those of preoperative and postoperative controls. Perioperative data included operation time, blood loss, volume of transfused blood, and length of hospital stay.Results:Craniotomy combined with springs resulted in less bleeding and lower transfusion rates than H-craniectomy. Although the spring technique requires 2 operations, the mean total operation time was similar for the methods. Of the 3 complications that occurred in the group treated with springs, 2 were spring-related. The compiled analysis of changes in cephalic index and partial volume distribution revealed that craniotomy combined with springs resulted in superior morphologic correction.Conclusion:The findings showed that craniotomy combined with springs normalized cranial morphology to a greater extent than H-craniectomy based on changes in cephalic index and total and partial ICVs over time.CLINICAL QUESTION/LEVEL OF EVIDENCE:Therapeutic, III.
Objective: Surgical correction of unicoronal synostosis (UCS) entails extensive cranioplasties which do not address facial scoliosis. This paper presents the first results with springs that motivated the shift from extensive cranioplasties to dynamic techniques for surgical correction of UCS. Methods: Two cases of UCS were operated with a linear osteotomy combined with springs. The deviation in facial symmetry (orbital dystopia angle) and skull base angles were measured on pre and postoperative computed tomography scans until 3 years of age. Results: The facial scoliosis was corrected. At spring removal, the orbital dystopia angle had gone from a 9.2 to 13.2-degree deviation preoperatively to a 0.5 to 0.9-degree overcorrection compared with the ideal 0-degree deviation. Also, the skull base deviation improved. Conclusion: Linear osteotomy combined with springs corrects the facial scoliosis in UCS. These cases indicate that dynamic methods may be beneficial for improving the results of surgical correction of UCS.
Background: This study assessed the diagnostic yield of high-throughput sequencing methods in a cohort of craniosynostosis (CS) patients not presenting causal variants identified through previous targeted analysis.Methods: Whole-genome or whole-exome sequencing (WGS/WES) was performed in a cohort of 59 patients (from 57 families) assessed by retrospective phenotyping as having syndromic or nonsyndromic CS.Results: A syndromic form was identified in 51% of the unrelated cases. A genetic cause was identified in 38% of syndromic cases, with novel variants detected in FGFR2 (a rare Alu insertion), TWIST1, TCF12, KIAA0586, HDAC9, FOXP1, and NSD2. Additionally, we report two patients with rare recurrent variants in KAT6A and YY1 as well as two patients with structural genomic aberrations: one with a 22q13 duplication and one with a complex rearrangement involving chromosome 2 (2p25 duplication including SOX11 and deletion of 2q22). Moreover, we identified potentially relevant variants in 87% of the remaining families with no previously detected causal variants, including novel variants in ADAMTSL4, ASH1L, ATRX, C2CD3, CHD5, ERF, H4C5, IFT122, IFT140, KDM6B, KMT2D, LTBP1, MAP3K7, NOTCH2, NSD1, SOS1, SPRY1, POLR2A, PRRX1, RECQL4, TAB2, TAOK1, TET3, TGFBR1, TCF20, and ZBTB20.Conclusion: These results confirm WGS/WES as a powerful diagnostic tool capable of either targeted in silico or broad genomic analysis depending on phenotypic presentation (e.g., classical or unusual forms of syndromic CS).
INTRODUCTION: Fronto-orbital remodelling for metopic synostosis is an extensive operation with substantial blood loss, particularly from emissary veins in the glabellar region. One possibility to reduce blood loss may be to stage dissection and cauterise anomalous emissary veins before dissecting in the subperiostal plane. OBJECTIVE: The aim of the present study was to compare perioperative bleeding using a staged dissection in the glabellar region with the traditional subperiostal dissection technique during surgery for metopic synostosis. METHODS: All consecutive patients operated for metopic synostosis with the new staged dissection technique (T2) were included. For comparison, the most recent equal number of cases operated with the traditional dissection technique (T1) were included. Age, sex, weight, surgical technique (spring or bone graft), perioperative blood loss, perioperative blood pressure, per- and postoperative blood transfusion, operation time and length of hospital stay were registered. RESULTS: A total of 80 patients were included; 40 T1 and 40 T2, respectively. Perioperative blood loss was significantly reduced with the new staged dissection technique. Blood loss in absolute numbers was reduced from 160.0 (120-240) (median and (interquartile range)) ml to 150 (102.5-170.0) ml, p=0.028. Blood loss in relation to patient weight was reduced from 24.2 ml/kg (15.3-33.3) to 18.7 (16.6-23.1) ml/kg, p=0.024. As percentage of total blood volume, blood loss was reduced from 32.3 (20.3-32.3) % to 29.9 (18.4-30.8) %, p=0.024. No other variables differed significantly between the techniques. CONCLUSION: In summary, staged dissection technique in the glabellar region, allowing control of the emissary veins, reduces perioperative blood loss during surgery for metopic synostosis.
Background: This study evaluated spring-assisted posterior vault expansion (SA-PVE) in children aged > 2 years with craniosynostosis and signs of high intracranial pressure (ICP). Methods: We retrospectively analysed all consecutive patients aged > 2 years and operated with SA-PVE between 2018 and 2020 at the Craniofacial Center at Sahlgrenska University Hospital, Sweden. During the procedure, a circumferent occipital bone flap extending below the torcula was created and remained attached to the dura. Intracranial volumes (ICVs) were calculated from computed tomography (CT) images, and demographic data and information regarding symptoms and signs of high ICP were collected. Results: The study included eight patients [Crouzon/Pfeiffer (n n = 4), multiple craniosynostosis (n n = 3), and secondary synostosis (n n = 1)1. Median age at SA-PVE was 3.8 years (range: 2.5-12.8 years), and springs were removed after a median of 5.5 months (range: 2.3-8.3 months). The median operating time was 164 min (range: 102-221 min), and estimated blood loss was 4.5 mL/kg body weight (range: 1.4-59.1 mL/kg body weight), with 50% of patients receiving a blood transfusion. The median increase in ICV was 206 cm3 3 (range: 122-344 cm3) 3 ) representing an 18.7% increase (range: 7.9-24.1%; p = 0.01). We observed no major perioperative complications, and symptoms related to high ICP were improved or absent at clinical follow-up. Conclusion: These results demonstrated that SA-PVE involving creation of a large occipital bone flap including the torcula as a safe and effective surgical treatment in children aged >2 years with craniosynostosis and elevated ICP.
Craniosynostosis is traditionally treated with extensive cranial vault reconstructions (CVRs). Although less invasive techniques, such as endoscopic strip craniectomy with postoperative helmet therapy, have been successful, they also present difficulties. An alternative method is distraction osteogenesis using either manually controlled devices or specially designed springs. In this study, the authors provide the first comparison of spring-assisted surgery (SAS) with CVR for the treatment of unilambdoid synostosis (ULS). Fourteen consecutive patients (8 CVR and 6 SAS) treated for ULS at Sahlgrenska University Hospital between 2005 and 2018 were included. Skull shape and deviations were evaluated using previously defined measurement points on 3-dimensional computed tomography scans preoperatively, at spring removal, and at 3 years of age. Posterior and middle cranial fossa (PCF and MCF, respectively), skull-base cant, facial twist, and mastoid bulge (MB) were measured, and clinical data were obtained from chart reviews. The results indicated that at the 3-year follow-up, PCF, MCF, and MB improved in both groups, with no significant difference in outcome observed between methods. In the SAS group, duration of operation [61±27 min (mean±SD)] and perioperative bleeding (3.5±2.8 mL/kg body weight) were both significantly lower relative to the CVR group (P<0.05). These findings showed that both SAS and CVR resulted in similar improvements in treating ULS, although neither produced complete normalization of skull shape. The results suggest that early diagnosis and operation allow less extensive SAS to be performed without adversely affecting the results.
Objective We assessed the prevalence of guardian-reported reading difficulties in children treated for non-syndromic craniosynostosis (NSC) and in relation to the location of the closed suture. Additionally, we determined correlations with guardian-reported neurodevelopmental disorders (NDDs) and associations between reported reading ability, sex, timing of surgical intervention, parental education, and heredity of reading difficulties in guardians. Design Cross-sectional, prospective, population-based study. Setting Tertiary hospital. Participants The cohort included 127 participants (aged 9-10 years) treated for NSC (76 sagittal, 38 metopic, 9 unicoronal, and 1 each of bicoronal, lambdoid, frontosphenoidal, and multisuture NSC). Main outcome measures The prevalence of guardian-reported reading difficulties was defined as a score ≥8 out of 14 points on the Short Dyslexia Scale. We determined associations between reported reading ability and reported NDDs through binomial regression analysis. Results The cohort demonstrated a 14.2% risk of of guardian-reported reading difficulties, with sagittal, metopic, and unicoronal NSCs exhibiting respective prevalences of 10.5%, 18.4%, and 23.1%. NDDs were reported in 22% of participants and significantly associated with reading difficulties. Conclusions The results indicated that participants with sagittal NSC showed the lowest risk of reading difficulties. Additionally, we found that NDDs represent significant risk factors for guardian-reported reading difficulties across the patient cohort. These findings underscore the need for targeted screening and support, especially for patients with metopic and unicoronal NSC, to guide clinical and educational decisions.
OBJECTIVE: Historically, there have been few quantita-tive methods for effectively evaluating outcomes after surgery for craniosynostosis. In this prospective study, we assessed a novel approach for detecting possible post-surgery brain injury in patients with craniosynostosis.METHODS: We included consecutive patients operated on for sagittal (pi-plasty or craniotomy combined with springs) or metopic (frontal remodeling) synostosis at the Craniofacial Unit at Sahlgrenska University Hospital, Gothenburg, Sweden, from January 2019 to September 2020. Plasma concentrations of the brain-injury biomarkers neurofilament light (NfL), glial fibrillary acidic protein (GFAP), and tau were measured immediately before in-duction of anesthesia, immediately before and after sur-gery, and on the first and the third postoperative days using single-molecule array assays.RESULTS: Of the 74 patients included, 44 underwent craniotomy combined with springs for sagittal synostosis, 10 underwent pi-plasty for sagittal synostosis, and 20 un-derwent frontal remodeling for metopic synostosis. Compared with baseline, GFAP level showed a maximal significant increase at day 1 after frontal remodeling for metopic synostosis and pi-plasty (P = 0.0004 and P = 0.003, respectively). By contrast, craniotomy combined with springs for sagittal synostosis showed no increase in GFAP. For neurofilament light, we found a maximal significant increase at day 3 after surgery for all proced-u res, with significantly higher levels observed after frontal remodeling and pi-plasty compared with craniotomy com-bined with springs (P < 0.001).CONCLUSIONS: These represent the first results showing significantly increased plasma levels of brain-injury biomarkers after surgery for craniosynostosis. Furthermore, we found that more extensive cranial vault procedures resulted in higher levels of these biomarkers relative to less extensive procedures.
OBJECTIVE:Apert syndrome (AS) is a rare congenital craniofacial disorder that requires a multidisciplinary approach to treatment and multiple surgeries. Given that cleft palate (CP) is presented in some of these cases, this poses an additional risk of aggravating obstructed airways after closure. The timing and outcome of CP repair in these patients remains disputed and requires additional attention. DESIGN:This retrospective analysis included patients diagnosed with CP and AS, born between 1950 and 2020, and treated at our institution. Data were collected from medical records and evaluated using descriptive statistics. SETTING:Data analyses were conducted at Sahlgrenska University Hospital in Gothenburg, Sweden. PATIENTS/PARTICIPANTS:A registry of 83 patients with AS resulted in a cohort of 26 patients also presenting with CP. MAIN OUTCOME MEASURES:Postoperative complications, requirement for intensive care, and reoperations following CP repair. RESULTS:CP incidence among all registered patients was 31%. Patients undergoing CP repair at low age (mean: 22.5 months) tended to experience more frequent postoperative complications and requirements for intensive care. Among the evaluated cohort with medical records describing CP repair (n = 14), 29% experienced postoperative complications, all of which involved aggravation of obstructed airways. CONCLUSIONS:This study highlights the importance of airway assessment before and after CP repair in AS. The findings suggest that surgical outcomes might benefit from postponing CP repair, avoiding combined surgeries, and operating in two stages when indicated. However, additional and larger studies are required.
Singe-suture craniosynostosis (SSC) describes the premature fusion of one cranial suture, which restricts cranial growth and consequently results in unaffected regions presenting a compensatory expansion. Surgery can redistribute intracranial volume, reduce the risk of elevated intracranial pressure, and improve head shape, potentially leading to improved neurocognitive function and social acceptance. However, there is limited evidence that surgery for SSC improves neurocognitive function and social acceptance. Given the inherent surgical risks and uncertainty of outcomes, the conditions under which this surgery should be allowed remain uncertain. Here, we discuss ethical questions regarding the permissibility of surgery, value of neurocognitive function and social acceptance, research ethics associated with SSC, patient autonomy and parental roles, and the process of recommending surgery and obtaining consent. Because surgery for SSC has become a routine procedure, its practice now presents a relatively low risk of complications. Furthermore, having acquired an understanding of the risks associated with this surgery, such knowledge fulfils the principle of non-maleficence although not beneficence. Thus, we advocate that surgery should only be offered within Institutional Review Board-approved research projects. In these situations, decisions concerning enrollment in scientific research involves health care providers and parents or guardians of the child, with the former acting as gate-keepers upon recognition of a lack of coping skills on the part of the parent or guardian in dealing with unforeseen outcomes. To minimize associated surgical risks and maximize its benefits, there exists a moral obligation to refer patients only to highly specialized centers.
Abstract: Premature craniosynostosis is a rare condition, with a wide range of incidence estimations in the literature. The aim of this study was to establish the current incidence among the Swedish population. Since the surgical care for these children is centralized to the 2 centers of Sahlgrenska University Hospital and Uppsala University Hospital, the 2 craniofacial hospital registries were examined for surgically treated children, all having a computed tomography verified diagnosis. Results show an incidence of 7.7 cases per 10,000 live births, including 0.60/10,000 syndromic craniosynostosis. Due to information programs among health care staff and a system for early diagnosis through rapid communication, these results seem to mirror the true incidence of craniosynostosis in the Swedish population. The updated incidence data will facilitate healthcare planning and make future studies of possible changes in craniosynostosis incidence more accurate.
Supplemental Digital Content is available in the text Abstract In this retrospective study, the authors determined changes in intracranial volume (ICV) and cephalic index (CI) in patients with sagittal craniosynostosis and operated with craniotomy combined with either 2 or 3 springs. The authors included patients (n = 112) with complete follow-up that had undergone surgical correction for isolated sagittal craniosynostosis with craniotomy combined with springs between 2008 and 2017. All patients underwent computed tomography examination preoperative, at the time of spring extraction, and at 3 years of age. Intracranial volume was measured using a semiautomatic MATLAB program, and CI was calculated as the width/length of the skull. The authors found that craniotomy combined with 2 springs increased the ICV from a preoperative value of 792 ± 113 mL (mean ± standard deviation) to 1298 ± 181 mL at 3 years of age and increased the CI from 72.1 ± 4.1 to 74.6 ± 4.3, whereas craniotomy combined with 3 springs increased the ICV from 779 ± 128 mL to 1283 ± 136 mL and the CI from 70.7 ± 4.3 to 74.8 ± 3.7. The relative increase in ICV was 65 ± 21% in the two-spring group and 68 ± 34% in the three-spring group (P value = 0.559), and the relative increase in CI was 3.6 ± 3.3% in the two-spring group as compared with 6.0 ± 5.0% in the three-spring group (P = 0.004). These findings demonstrated that use of 3 springs resulted in additional absolute and relative CI-specific effects as compared with 2 springs during the time when the springs were in place, with this effect maintained at 3 years of age.