New Simple 3-Dimensional Computed Tomogram Classification Leading to Successful Conservative Treatment in 51 Atlanto-Axial Rotatory Fixation Children.

OBJECTIVE: to present a new and easy classification of atlanto-axial rotatory fixation (AARF) and to investigate the efficiency of conservative treatment of AARF. BACKGROUND: Although there is a precise definition and diagnostic classification of AARF, there is still significant difficulty in measuring the atlas and axis angles because all of the atlas or axis cannot be seen in a certain 2-dimensional computed tomogram image. In addition, some recent case reports showed that long-term conservative treatment can reduce pediatric AARFs, even that are severe or chronic. METHODS: Fifty-one children with AARF were analyzed retrospectively with new 3-dimensional computed tomogram (3DCT)-based AARF classification; the mean age was 72.7 ± 35.2 months (19-139 months). In the new AARF classification, type 1 was defined as that when the C1C2 angle is not 0° on midline and type 2 as that when the C1C2 angle is 0° on the midline. RESULTS: All 7 children with AARF type 1 were treated successfully only with Halter tractions. Twenty among 44 children with type 2 did not show any difference in improvement compared with not-treated 24 children with type 2. CONCLUSION: The first new AARF classification based on 3DCT appears to be easy to use and even the most severe children with AARF may be managed only with conservative treatment such as long-term Halter traction.

Relationships between Head Circumference Percentile, Lumbar Puncture Pressure, and Cerebrospinal Fluid Space in Young Children: Increased Cerebrospinal Space and Pressure May Result in Compensatory Enlargement of Head Circumference Only in the Infant Period.

BACKGROUND: The aim of this study was to retrospectively evaluate and analyze the relationships between head circumference percentile (HCP), lumbar puncture pressure (LPP), and cerebrospinal fluid (CSF) space. METHODS: The 88 patients were divided into 3 age groups (group 1, up to 12 months; group 2, 12-36 months; group 3, 36-72 months). RESULTS: In group 1 (n = 40), there was a significant positive correlation of the HCP with the LPP (r =0.414, p =0.008), Evans ratio (r =0.365, p =0.021), and thickness of subdural hygroma (SDHG; r =0.403, p =0.010). Group 2 (n = 29) revealed a significant positive correlation between the LPP and the thickness of SDHG (r =0.459, p =0.012). Group 3 (n = 19) showed no significant correlation among these factors. Overall, age was related with SDHG thickness both in infants and toddlers, while HCP was related with LPP, Evans ratio, and SDHG thickness only in infants, and LPP was related with SDHG thickness only in toddlers. CONCLUSION: We suggest that increased cerebrospinal space and pressure may result in compensatory enlargement of head circumference only in the infant period, and the SDHG thickness decreases with age during the infant and toddler phases.

Trimming of Absorbable Plates and Screws through Smoothing by Multiple Sonic Activation Procedures Can Increase Local Tissue Reactions in Children with Cranial Fixations.

OBJECTIVE: The aim of this paper was to investigate the local reactions due to the melting of absorbable plates and screws after trimming through smoothing by multiple sonic activation procedures (MSAP). BACKGROUND: Drilling or smoothing by MSAP is performed for the trimming of the absorbable plates and screws for cranial fixation in children. Compared to drilling, smoothing by MSAP is suspected to more commonly cause local tissue reactions; thus, the issue was examined herein. METHODS: For 90 children with smoothing by MSAP and 83 children with drilling procedures who underwent cranial fixation using absorbable plates and screws, the type, time of onset, and incidence of the local reactions were investigated. RESULTS: Swelling was the most common reaction, followed by inflammatory reactions with itching, heating, skin-penetrating drainage, and pus formation. The mean time of onset of the local reaction was 10.0 ± 2.3 months after surgery. Local reactions occurred in 30% of the children in the group with smoothing by MSAP, and in 7.2% of the children in the group with drilling, showing a statistically significant difference between the two groups (p < 0.001). CONCLUSION: It was concluded that drilling rather than smoothing by MSAP to change the shapes of the absorbable plates and screws in cranial fixation can reduce the local reactions.

The Total Calvarial Remodeling with Transsutural Distraction Osteogenesis of 21 Cases of Craniosynostosis: New, Efficient, Safe and Natural Method in Craniosynostosis Surgery.

INTRODUCTION: The majority of the present distraction osteogenesis techniques involve local site expansion that only produces localized decompression and affords limited decompression and cosmetic results. We designed a new surgical procedure, total calvarial transsutural distraction osteogenesis (TSuDO). METHODS: We performed total calvarial TSuDO surgical procedures in 21 children. The total calvarial TSuDO method consisted of suturectomy and distraction for the sagittal, bicoronal and bilambdoid sutures. RESULTS: The mean surgery duration was 110 ± 16 min, the mean transfusion volume was 38 ± 45 ml, an average 4.1 ± 0.4 distractors were applied with a mean latency period of 3.3 ± 0.9 days. The mean activation period was 45 ± 18 days with a consolidation period of 54 ± 23 days. There were 3 complication cases of early removal of the distractors: 1 boy with transient 6th cranial nerve palsy accompanied by fever and 2 children with mild pus discharge from the distractor sites. Preoperative lumbar puncture pressures decreased significantly after distractor removal secondary to surgery (p < 0.001). The preoperative cranium size increased significantly (p < 0.001). CONCLUSION: Total calvarial TSuDO is a simple and safe procedure that may produce wide generalized decompression and good cranial configurations that most closely resemble normal skulls.

Abducens Nerve Palsy Following Expansion Cranioplasty with Distraction Osteogenesis.

Childhood abducens nerve palsy can occur as a result of trauma, tumour, vasculopathic disease, elevated intracranial pressure, infection, inflammation, and congenital or idiopathic causes. The authors present two cases of unilateral abduction deficit secondary to a recent trans-sutural distraction osteogenesis (TSuDO) operation for craniosynostosis. After distractor removal, the problem resolved spontaneously over 2-4 months in both cases. This is a first reported case of sixth nerve palsy as a complication of TSuDO operation.

Effect of ultrasound treatment on brain edema in a traumatic brain injury model with the weight drop method.

BACKGROUND: For the treatment of traumatic brain edema, an efficient modality has not yet emerged. There have been many studies to date which have reported the employment of low-frequency ultrasound for blood-brain barrier disruption (BBBD). However, the authors have observed that low-intensity ultrasound increases water permeability without cellular damage in cartilage cells. We have therefore attempted to observe the effects of applying this low-intensity ultrasound to an experimental animal model. METHODS: A traumatic brain injury rat model was established according to the weight drop method developing the traumatic brain edema. The degree of BBBD was measured by the changes in the water content and spectrophotometric absorbance of Evans blue dye in the cerebrum after low-frequency ultrasound. RESULTS: The cerebral water content levels showed that the BBBD gradually increased after impact and thereafter decreased after 6 h. After low-frequency ultrasound exposure, the values of water content and spectrophotometric absorbance of Evans blue dye were the lowest at 0 h, and were increased at 2 and 5 h of ultrasonic exposure (after impact). CONCLUSION: We suggest that traumatic brain edema in the rat model may be alleviated by low-frequency ultrasound, and low-frequency ultrasound might be proposed as a novel treatment modality for brain edema.

Sterol regulatory element-binding protein (SREBP)-1-mediated lipogenesis is involved in cell senescence.

Increased cell mass is one of the characteristics of senescent cells, but this event has not been clearly defined. When subcellular organellar mass was estimated with organelle-specific fluorescence dyes, we observed that most membranous organelles progressively increase in mass during cell senescence. This increase was accompanied by an increase in membrane lipids and augmented expression of lipogenic enzymes, such as fatty acid synthase (FAS), ATP citrate lyase, and acetyl-CoA carboxylase. The mature form of sterol regulatory element-binding protein (SREBP)-1 was also elevated. Increased expression of these lipogenic effectors was further observed in the liver tissues of aging Fischer 344 rats. Ectopic expression of mature form of SREBP-1 in both Chang cells and primary young human diploid fibroblasts was enough to induce senescence. Blocking lipogenesis with FAS inhibitors (cerulenin and C75) and via siRNA-mediated silencing of SREBP-1 and ATP citrate lyase significantly attenuated H(2)O(2)-induced senescence. Finally, old human diploid fibroblasts were effectively reversed to young-like cells by challenging with FAS inhibitors. Our results suggest that enhanced lipogenesis is not only a common event, but also critically involved in senescence via SREBP-1 induction, thereby contributing to the increase in organelle mass (as a part of cell mass), a novel indicator of senescence.

The trans-sutural distraction osteogenesis for 22 cases of craniosynostosis: a new, easy, safe, and efficient method in craniosynostosis surgery.

BACKGROUND: Distraction osteogenesis for the treatment of craniosynostosis is becoming more widely used as it is simple, there are less transfusions, and a decreased incidence of complications, although a secondary procedure for the removal of the distractors is necessary. However, to date all previous procedures have still been complicated. The authors present a novel trans-sutural distraction osteogenesis method (TSuDO) for the treatment of all types of craniosynostosis. METHODS: The TSuDO consisted of simple suturectomy of the pathologic suture followed by direct distraction of the suturectomy site only. Types of TSuDO conducted were sagittal TSuDO in 6 patients, coronal TSuDO in 5 patients, unilateral coronal TSuDO in 8 patients, lambdoid TSuDO in 2 patients, and metopic TSuDO in 1 patient (total = 22). Mean age was 9.3 ± 12.7 months. RESULTS: The mean operation time was 143.6 ± 50.2 min, and mean total transfusion volume of blood components was 131.1 ± 78.3 ml. Immediate correction of the abnormal head contour after distraction was observed in all patients, and no complications were encountered except for 1 patient whose distractor malfunctioned and 2 who showed prolonged discharges from the pin sites (controlled by antibiotics). CONCLUSION: TSuDO is a simple, effective, and safe method for the treatment of all types of craniosynostosis, and is especially effective for the correction of unilateral coronal craniosynostosis.

A Korean family with the Muenke syndrome.

The Muenke syndrome (MS) is characterized by unicoronal or bicoronal craniosynostosis, midfacial hypoplasia, ocular hypertelorism, and a variety of minor abnormalities associated with a mutation in the fibroblast growth factor receptor 3 (FGFR3) gene. The birth prevalence is approximately one in 10,000 live births, accounting for 8-10% of patients with coronal synostosis. Although MS is a relatively common diagnosis in patients with craniosynostosis syndromes, with autosomal dominant inheritance, there has been no report of MS, in an affected Korean family with typical cephalo-facial morphology that has been confirmed by molecular studies. Here, we report a familial case of MS in a female patient with a Pro250Arg mutation in exon 7 (IgII-IGIII linker domain) of the FGFR3 gene. This patient had mild midfacial hypoplasia, hypertelorism, downslanting palpebral fissures, a beak shaped nose, plagio-brachycephaly, and mild neurodevelopmental delay. The same mutation was confirmed in the patient's mother, two of the mother's sisters and the maternal grandfather. The severity of the cephalo-facial anomalies was variable among these family members.

Rotating distraction osteogenesis in 23 cases of craniosynostosis: comparison with the classical method of craniotomy and remodeling.

BACKGROUND: The currently employed technique of distraction osteogenesis (DO) for the surgical treatment of craniosynostosis (CS) is commonly performed due to advantages such as shorter operation time, less bleeding and thus less need for transfusions and a lower risk of infections. Several surgical techniques for the various types of CS have been reported, but a uniform surgical method is as yet unavailable. METHODS: We compared 23 patients who underwent rotating DO (RDO) with 15 patients who received conventional craniotomy and remodeling (CR). RDO consisted of suturectomy of the pathologic suture and resection of the bone flap to allow wide suture separation for distraction and open-door rotation. RESULTS: The mean operation duration in the RDO group was 255.9 +/- 97.8 min, which was significantly shorter than the 414.0 +/- 106.9 min for the CR group (p = 0.0001). Perioperative complications in the RDO group consisted of 2 cases of distractor breakage and 2 cases of minimal pus discharge, while in the CR patients there was 1 case of postoperative epidural hematoma and 1 case of spontaneous bone fracture. CONCLUSION: We suggest that RDO may be a valid and efficient method for treating children with CS by DO by expanding the intracranial volume and correcting abnormal skull contour shapes.

Abusive Head Traumas in 4 Infants.

Pediatric abusive head trauma (AHT) is a serious, repeated child abuse that causes grave brain damage. In Korea, AHT cases have been reported rarely, especially infants. We present 4 cases of AHT in infants diagnosed in our institution during last 2 years. We collected the demographic data, ophthalmologic examination, imaging study, and outcomes. The mean age was 7.2 months, and 2 infants were girls and the others were boys. All four were admitted with no history of head trauma, and among them 2 patients presented with an episode of seizure and respiratory arrest with no history of head trauma. The initial mental status was semi-coma in 3 cases, and stupor in 1 case. There were multiple retinal hemorrhages in both eyes in 2 cases; one had multiple old fractures on the extremities and another child showed multiple skull fractures. All patients underwent emergent surgery for acute bilateral subdural hemorrhages; 3 had craniotomy and another had burr-hole drainage. Two children expired and the other 2 are in vegetative status. The AHT has recently become more frequent in Korea so that neurosurgeons must alert AHT even in infants with head trauma.

Hypothesis for lateral ventricular dilatation in communicating hydrocephalus: new understanding of the Monro-Kellie hypothesis in the aspect of cardiac energy transfer through arterial blood flow.

Many theories have been postulated to date regarding mechanisms involved in non-enlargement of the subarachnoid space and enlargement of the ventricles in patients with communicating hydrocephalus, but none have been prove to be definite. Cerebrospinal fluid (CSF) movement is known not to bulk flow but rather pulsatile flow that develops from the energy of the blood flow ejected from the heart, in an isolated system of the intracranial cavity surrounded by a solid skull, as in the Monro-Kellie hypothesis. The authors attempt to explain the mechanisms involved in selective enlargement of the lateral ventricle in patients with communicating hydrocephalus by re-addressing the Monro-Kellie hypothesis with respect to cardiac energy transfer and dissipation by the Windkessel effect. The authors present a concept whereby the large energy of blood flow from the heart that is conveyed to the intracranial artery, arteriole, brain parenchyme, ventricle, and CSF within the confined cranial space as in the Monro-Kellie hypothesis, and which ultimately dissipates to maintain an intracranial energy equilibrium. In the same context, if, for some reason the intracranial equilibrium in the energy transfer and dissipation is changed or disrupted, then structural changes would have to occur to achieve and maintain a new intracranial equilibrium. We postulate that the above described mechanisms are those responsible for the development enlarged of lateral ventricles in patients with communicating hydrocephalus. Structural enlargement of the lateral ventricles in communicating hydrocephalus is a consequence of CSF pathway obstruction and resultantly increased CSF absorption function in the lateral ventricle which markedly increases the pulsatile CSF energy flow returning to the lateral ventricles, thus causing collision of pulsatile CSF flow with the brain parenchyme at the ventricular wall, which subsequently leads to structural enlargement of the lateral ventricles. Also, the collision between the CSF pulsation and brain parenchyme pulsation reduces the Windkessel effect of the brain parenchyme which increases the intracranial artery pulse pressure, which in turn is transmitted to the CSF and increases CSF pulse pressure. This vicious circle results in the high pulse pressure within the lateral ventricle structurally dilating the lateral ventricle. Our theory also explains the relationship between ventricle dilatation and idiopathic intracranial hypertension, venous sinus thrombosis, achondroplasia.

The role of distraction osteogenesis in children with secondary craniosynostosis after shunt operation in early infancy.

BACKGROUND: Secondary craniosynostosis rarely develops within several months in infants or children after shunt operations in early infancy. However, conventional operations (CO) such as fronto-orbital advancement and total skull reshaping have not been efficient enough to expand the intracranial volume in children with secondary craniosynostosis. Recently, distraction osteogenesis (DO) was reported to be effective in treating most craniosynostosis cases. METHODS: We compared 9 children treated with DO and 3 children treated with CO who developed secondary craniosynostosis after shunt operation in early infancy. We measured the preoperative and follow-up head sizes with regard to head circumference, cephalometric intracranial volume, and intracranial volume estimated from the 3-dimensional computed tomogram. RESULTS: The mean intracranial volumes expanded by 10.5% in the DO group 1 month after surgery and by 13.1% in the CO group on the immediate postoperative day. Further expansion was observed 6 months postoperatively, i.e. 10.3 and 4.7% in the DO and CO groups, respectively. Operation time and anesthesia time were significantly shorter in DO compared to CO patients, and the volumes of the blood transfusions were also less for DO patients. CONCLUSION: We suggest that DO is probably more efficient and safer than CO in expanding the intracranial volume in children with secondary craniosynostosis.

Continuous Intracranial Pressure Monitoring in 24 Microcephalic Children with Developmental Delay: A Significant Portion of Microcephalic Children with Developmental Delay Have High Intracranial Pressure.

OBJECTIVE: The new direct gradual cranial expansion surgical technique has been used to treat children with postshunt microcephaly and slit ventricle syndrome. To evaluate the feasibility of this new surgical treatment, we studied intracranial pressure (ICP) in microcephalic children with developmental delay. METHODS: Mean ICP, age, sex, head size, and developmental assessments were compared in 24 microcephalic children with developmental delay who had had continuous ICP monitoring. RESULTS: Children studied included 9 boys and 15 girls with a mean age of 4.9 ± 2.0 years. Mean ICP was 18.7 ± 8.6 mm Hg. Children with high ICP had significantly lower age and higher B wave ratios than children with low ICP. There were no statistically significant differences in developmental scores and head sizes between children with high ICP and children with low ICP. In multiple linear regression analysis, we observed significantly increased risk of mean ICP elevation by B wave ratio and developmental score and decreased risk of mean ICP elevation by age, but not significantly increased risk of mean ICP elevation by head circumferences (z score). CONCLUSIONS: Our findings suggest that a portion of microcephalic children with developmental delay have high ICP that cannot be expected from head sizes, and high ICP has decreasing tendency with age.

Correlation of Neonatal Birth-Associated Greenstick Skull Fractures with Perinatal Factors and Long-Term Outcome: Children with a Greater Number of Greenstick Skull Fractures Showed Poor Results in Terms of Long-Term Neurodevelopment.

OBJECTIVE: Skull fractures caused by birth injury are mainly compression and linear fractures, but the incidence is known to be rare. It has been recently suggested, however, that greenstick fractures (GSFs) are more common than compression or linear fractures that are detected through 3-dimensional reconstructed computed tomography. Therefore, this study was conducted to determine the correlation of GSF with perinatal factors, the accompanying head injury factors, and the long-term outcomes in neonates. METHODS: A retrospective study was conducted on correlations between GSF and perinatal and head injury factors for 295 neonates. In 160 neonates, the correlation with long-term outcome was investigated. RESULTS: In 295 neonates, 47 cases had 3 or fewer GSFs, 66 cases had 4-6, 82 cases had 7-9, and 100 cases had 10 or more. The number of GSFs was significantly associated with gestational age and mode of delivery among the perinatal factors, with brain swelling and cephalohematoma among the head injury factors. It was also associated with long-term outcomes. The cut-off value of the number of GSFs for a poor outcome by the area under the receiver operating characteristic curve was 6 or greater. CONCLUSIONS: It was concluded that GSF most commonly occurs as a birth-related skull fracture and that birth-related GSF is associated with perinatal factors, birth-related head injuries, and deterioration of long-term development. Therefore, efforts should be made to prevent GSF at birth.

Endovascular internal trapping of traumatic pericallosal pseudoaneurysm with hydrogel-coated self-expandable coil in a child: a case report.

BACKGROUND: Traumatic intracranial pseudoaneurysms in children must be completely secured from the parent artery because of significant morbidity and mortality from the high risk of rebleeding. However, the trapping of the parent artery involves the risk of ischemia changes distal to the trapped artery and the perforator injury. We describe a first case in the literature of successful trapping in the short segment with hydrogel-coated self-expandable coil in a child with a traumatic pericallosal pseudoaneurysm. CASE DESCRIPTION: A 5-year-old boy was admitted to our institution after enduring a blunt trauma with a stuporous mentality. Initial neuroimaging revealed a small hemorrhage in the corpus callosum with subarachnoid hemorrhage. Two weeks later, computed tomogram showed new callosal hemorrhage and a 4.7 x 5-mm pseudoaneurysm of the right pericallosal artery with mental deterioration and weakness of lower extremity. An endovascular short segmental internal trapping (5 mm) of the right pericallosal artery was conducted to save collateral blood flow, using 2 hydrogel-coated self-expandable coils. The cerebral angiogram of immediately after the trapping and at 3 months' follow-up revealed that the aneurysm had been completely obliterated, with successful maintenance of the distal collateral flow from the contralateral pericallosal artery. The patient recovered with good clinical outcome. CONCLUSION: We suggest that short-segment occlusion by a hydrogel-coated self-expandable coil has become a good alternative for the treatment of traumatic pseudoaneurysms in the distal anterior cerebral artery, although the safety and reliability of this procedure is as yet not definitely proven.

New concept of cerebrospinal fluid dynamics in cerebral venous sinus thrombosis.

Cerebral venous sinus thrombosis develops as a consequence of sinus obstruction, leading to hindering of venous drainage, gradual edema and increased intracranial pressure (ICP). Intracerebral hemorrhage occurs, of which the symptoms may be alleviated by cerebrospinal fluid (CSF) drainage. Clinical brain function improvement may be directly attributed to the effect of the decreased ICP, or to the decreased pressure on the venous sinus which alleviates venous blood flow and sinus thrombosis. However, worsening, rather than improvement of symptoms are occasionally observed in patients after CSF drainage, and therefore it is as yet difficult to determine the precise indications for CSF drainage. The authors of this study suggest that external CSF drainage of sagittal sinus thrombosis may accelerate the sinus thrombosis and aggravate symptoms in such a patient. In other words, the sagittal sinus differs from other sinuses in that when sinus thrombosis develops, CSF absorption is impeded from the early stages, leading to a higher likelihood of ventricular dilatation, because most of the CSF are normally absorbed through the arachnoid villi and drain into the sagittal sinus. External CSF drainage and subsequently decreased ICP will improve sinus thrombosis after implementation of CSF drainage of the sagittal sinus thrombosis, but on the other hand, this decreased CSF drainage leads to decreased venous sinus blood flow, both of which may result in aggravation of the sinus thrombosis. However, it is also suggested that CSF drainage may be accomplished safely on the unilateral lateral sinus thrombosis because CSF drainage may alleviate venous sinus obstruction, and does not influence the sinus blood flow. We, authors of this study suggest that caution should be taken when external CSF drainage of the sagittal sinus thrombosis is performed to prevent further aggravation of intracranial pressure elevation.

Distractor breakage in cranial distraction osteogenesis for children with craniosynostosis.

Cranial distraction osteogenesis has been applied as a mode of therapy to patients with various types of craniosynostosis. Several minor complications during distraction have been reported in the previous literature, including infection, device exposure, and dislocation and distortion of the device. To our knowledge, this is the first report of 2 cases of spontaneous device breakage during cranial distraction osteogenesis. Two infant patients were diagnosed with shunt-induced microcephalies. The ages of the 2 patients were 8 and 12 months. Their head circumferences were 3 percentiles below that of normal children of the same age. Distraction osteogenesis advancement to the frontal skull and the orbital bar was performed with two distractors. We distracted a total of 7.0 and 14.4 mm at a rate of 0.6-1.5 mm per day before device breakage occurred 7 and 25 days after the distraction activation, respectively. Both patients underwent reoperation to exchange the broken device for further distraction. To prevent further device breakage, we suggest increasing the rate of distraction, placing stronger or more devices, or relieving the scalp retraction pressure probably by extensive dissection of the subcutaneous layers or multiple incisions into the galeal layers.

Intradural extracerebral choristoma. Case report and review of the literature.

BACKGROUND: Intracranial extracerebral neuroglial choristoma is a very rare entity. A cleft palate or a nasopharyngeal teratoma has been described as accompanying choristoma, but there are no observations of both anomalies being simultaneously present and combined. METHODS: An 8-month-old girl presented with seizures, without evidence of any other neurological abnormalities. Brain magnetic resonance imaging demonstrated a 2.0-cm-sized, round-shaped mass in the frontal midline. The T(1)- and T(2)-weighted images showed a well-circumscribed iso-signal intensity lesion with no gadolinium enhancement. RESULTS: Surgical exploration revealed a yellowish tumor mass with whitish soft tissue material within the tumor, adherence to the surrounding blood vessels, and therefore subtotal removal was performed. Pathologic examination was neuroglial choristoma with 1.5% of MIB-1 labeling index. The patient also had a cleft palate with a pinkish palatal mass and underwent repair of the cleft palate, and excision of mass that was a mature cystic teratoma on pathologic examination. Follow-up at 18 months later showed that there was no evidence of tumor regrowth or neurological deficit, and the neurological development was normal. CONCLUSION: The authors described a rare case of intracranial extracerebral neuroglial choristoma accompanied by both nasopharyngeal teratoma and cleft palate and suggested its benign nature from the low MIB-1 labeling index.

Image quality assessment of silent T2 PROPELLER sequence for brain imaging in infants.

OBJECTIVE: Infants are vulnerable to high acoustic noise. Acoustic noise generated by MR scanning can be reduced by a silent sequence. The purpose of this study is to compare the image quality of the conventional and silent T2 PROPELLER sequences for brain imaging in infants. METHODS: A total of 36 scans were acquired from 24 infants using a 3 T MR scanner. Each patient underwent both conventional and silent T2 PROPELLER sequences. Acoustic noise level was measured. Quantitative and qualitative assessments were performed with the images taken with each sequence. RESULTS: The sound pressure level of the conventional T2 PROPELLER imaging sequence was 92.1 dB and that of the silent T2 PROPELLER imaging sequence was 73.3 dB (reduction of 20%). On quantitative assessment, the two sequences (conventional vs silent T2 PROPELLER) did not show significant difference in relative contrast (0.069 vs 0.068, p value = 0.536) and signal-to-noise ratio (75.4 vs 114.8, p value = 0.098). Qualitative assessment of overall image quality (p value = 0.572), grey-white differentiation (p value = 0.986), shunt-related artefact (p value > 0.999), motion artefact (p value = 0.801) and myelination degree in different brain regions (p values ≥ 0.092) did not show significant difference between the two sequences. CONCLUSION: The silent T2 PROPELLER sequence reduces acoustic noise and generated comparable image quality to that of the conventional sequence. Advances in knowledge: This is the first report to compare silent T2 PROPELLER images with that of conventional T2 PROPELLER images in children.