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J Gordon McComb

Publications and source records attributed to J Gordon McComb.

At least 19 recordsLinked to original sources
PubMed2006

Epidural-cutaneous fistula in association with the Pott puffy tumor in an adolescent. Case report.

The Pott puffy tumor is a subperiosteal abscess associated with underlying osteomyelitis, most often of the frontal bone in conjunction with frontal sinusitis. Intracranial sequelae can include epidural abscess, subdural empyema, intraparenchymal abscess, meningitis, and dural venous thrombophlebitis, all with resultant neurological deterioration. Although once common, this entity has become rare since the introduction of antibiotic agents. The authors present an unusual case of a 14-year-old girl suffering from the Pott puffy tumor whose condition was further complicated by a draining epidural-cutaneous fistula and an epidural abscess.

Adolescent↗
PubMed2005

Craniopharyngiomas of childhood: the CHLA experience.

OBJECTIVE: To improve the outcome of children with craniopharyngiomas by analyzing how they were treated. METHODS: The records of patients who underwent operation at Childrens Hospital of Los Angeles (CHLA) from 1993 to 2004 were reviewed. RESULTS: Identified were 19 girls and 16 boys with an age range from 9 days to 16 years (mean 7 years, mode 3 years). Tumor control was achieved in 34 of 35 patients and was accomplished with reasonable outcome in terms of neurological deficits and overall level of function. In 25 patients, complete tumor resection was obtained with surgery alone, 18 with the first resection, and 7 with repeat operative intervention. Nine children received radiation therapy after the first or second recurrence. On retrospective review, there were no consistently identifiable features that would lead one to determine preoperatively which tumors would fall into a given category. CONCLUSION: We believe that the surgeon must determine a preoperative plan that maximizes the chance for a gross total removal of the craniopharyngioma. The biggest challenge intraoperatively is to determine whether to continue with the attempt at gross total removal or stop short of that goal before producing a significant irreversible neurological deficit. A staged removal using different operative corridors also needs to be considered.

Adolescent↗
PubMed2005

Differentiation of choroid plexus tumors by advanced magnetic resonance spectroscopy.

OBJECT: The management of pediatric intraventricular tumors is highly dependent on identification of the tumor type. Choroid plexus papillomas, a common intraventricular tumor in children, can be difficult to distinguish radiographically from choroid plexus carcinomas and other common pediatric central nervous system (CNS) tumors. In this study to overcome the limitations of current noninvasive imaging modalities, the authors use novel magnetic resonance (MR) spectroscopy techniques in vivo to elucidate the identifying biochemical features of choroid plexus tumors that may facilitate diagnosis and treatment. METHODS: Based on an Internal Review Board-approved protocol, six children with newly diagnosed, untreated intraventricular brain tumors were identified. On retrospective review, this series included three choroid plexus papillomas and three choroid plexus carcinomas. Single-voxel proton MR spectroscopy with a short echo time was performed, and absolute metabolite concentrations (in mmol/kg) were determined using fully automated quantitation. These results were compared with MR spectroscopy profiles obtained in 54 other untreated CNS neoplasms in children. The myo-inositol (mI) level was significantly higher in choroid plexus papillomas (> 10 mmol/kg), uniquely distinguishing these tumors from choroid plexus carcinomas and all other tumors. Choroid plexus carcinomas, on the other hand, had significantly elevated levels of choline when compared with choroid plexus papillomas. CONCLUSIONS: In this study the authors find that mI is a biochemical constituent that uniquely identifies choroid plexus papillomas and can be used as a noninvasive means of diagnosis and for follow-up evaluations in patients with this disease.

Adolescent↗
PubMed2005

Atypical teratoid/rhabdoid tumors of the central nervous system: management and outcomes.

OBJECT: Atypical teratoid/rhabdoid tumors (ATRTs) represent a relatively newly categorized neoplastic entity. They commonly present in childhood, and have a rapidly progressive clinical course with a survival time of less than 1 year. Treatment regimens have been nonuniform. In this retrospective review of patients with ATRTs who were treated at the authors' institution according to a uniform protocol, the goal was to assess the efficacy of the treatment and its outcome. METHODS: Over a 7-year period, ATRT was diagnosed in 11 patients (six boys and five girls). The median age of the patients was 61 months, and their ages ranged from 3 months to 17 years. Signs and symptoms began, on average, a little more than 1 month before diagnosis and included the following: headache (36%), nausea and vomiting (46%), lethargy (18%), seizures (27%), cranial nerve findings (46%), ataxia (18%), long tract findings (18%), and hydrocephalus (46%). Tumor location was cortical in four patients, in the pineal region in four, in the posterior fossa in two, and spinal in one. In one patient disseminated disease was revealed on the initial imaging study; seven patients had disseminated tumor subsequently. Treatment consisted of chemotherapy in 11 patients, chemotherapy and local radiation in five, and chemotherapy and craniospinal radiation in three. Six patients are alive, three have died, and two were lost to follow-up review. The mean time to death was 24 months, and ranged from 2 to 67 months. Among the surviving patients the mean duration of follow up is 18.5 months and ranges from 2 to 37 months. The median time to progression was 3.5 months. CONCLUSIONS: Atypical teratoid/rhabdoid tumors are malignant lesions with rapid progression. Further study is necessary to determine the efficacy of therapy.

Adolescent↗
PubMed2005

Proton-decoupled 31P MRS in untreated pediatric brain tumors.

Proton-decoupled (31)P and (1)H MRS was used to quantify markers of membrane synthesis and breakdown in eight pediatric patients with untreated brain tumors and in six controls. Quantitation of these compounds in vivo in humans may provide important indicators for tumor growth and malignancy, tumor classification, and provide prognostic information. The ratios of phosphoethanolamine to glycerophosphoethanolamine (PE/GPE) and phosphocholine to glycerophosphocholine (PC/GPC) were significantly higher in primitive neuroectodermal tumors (PNET) (16.30 +/- 5.73 and 2.97 +/- 0.93) when compared with controls (3.42 +/- 1.62, P < 0.0001 and 0.45 +/- 0.13, P < 0.0001) and with other tumors (3.93 +/- 3.42, P < 0.001 and 0.65 +/- 0.30, P < 0.0001). Mean PC/PE was elevated in tumors relative to controls (0.48 +/- 0.11 versus 0.24 +/- 0.05, P < 0.001), but there was no difference between PNET and other tumors. Total choline concentration determined with quantitative (1)H MRS was significantly elevated (4.78 +/- 3.33 versus 1.73 +/- 0.56 mmol/kg, P < 0.05), whereas creatine was reduced in tumors (4.89 +/- 1.83 versus 8.28 +/- 1.50 mmol/kg, P < 0.05). A quantitative comparison of total phosphorylated cholines (PC+GPC)/ATP measured with (31)P MRS and total choline measured with (1)H MRS showed that in tumors a large fraction of the choline signal (>54 +/- 36%) was not accounted for by PC and GPC. The fraction of unaccounted choline was particularly large in PNET (>78 +/- 7%). The pH of tumor tissue was higher than the pH of normal brain tissue (7.06 +/- 0.03 versus. 6.98 +/- 0.03, P < 0.001).

Brain↗
PubMed2005

Untreated pediatric primitive neuroectodermal tumor in vivo: quantitation of taurine with MR spectroscopy.

PURPOSE: To retrospectively investigate whether quantitation of taurine (Tau) concentrations with proton magnetic resonance (MR) spectroscopy in vivo improves the differentiation of primitive neuroectodermal tumors (PNET) from other common brain tumors in pediatric patients. MATERIALS AND METHODS: The institutional review board approved this review of clinical data; it was not necessary to obtain parental consent. This study was HIPAA compliant. Single-voxel proton spectroscopy was added to the preoperative MR imaging work-up of 29 patients (12 boys and 17 girls; mean age, 6.5 years +/- 3.5) with untreated brain tumors; 13 had PNETs, and 16 had other tumors. Absolute concentrations (measured in millimoles per kilogram of brain tissue) of metabolites of the proton spectrum were determined. Student t tests were used for statistical comparisons. RESULTS: Elevated absolute Tau concentration proved to be the most significant metabolite in the differentiation of PNETs from other tumors (6.09 mmol/kg +/- 2.24 vs 0.76 mmol/kg +/- 0.95, P < .001). PNETs also exhibited a higher ratio of Tau relative to choline (1.21 +/- 0.48 vs 0.28 +/- 0.39, P < .001), a higher ratio of Tau relative to creatine (1.28 +/- 0.44 vs 0.38 +/- 0.67, P < .001), a reduced a ratio of N-acetyl-aspartate relative to choline (0.20 +/- 0.20 vs 0.79 +/- 0.56, P < .001), and an increased choline concentration (5.30 mmol/kg +/- 1.64 vs 3.08 mmol/kg +/- 2.53, P < .05). Tau concentrations ranged from 2.62 to 11.15 mmol/kg in individual patients with a PNET. CONCLUSION: Single-voxel quantitative (1)H MR spectroscopy performed in patients with untreated pediatric brain tumors showed that the Tau concentration was significantly elevated in PNETs and was useful in the differentiation of PNETs from other tumors.

Child↗
PubMed2005

Craniotomy for fenestration of multiloculated hydrocephalus in pediatric patients.

OBJECTIVE: To assess the treatment of progressive multiloculated hydrocephalus by craniotomy for microsurgical fenestration of cerebrospinal fluid (CSF) compartments to minimize the number of ventricular catheters. METHODS: We studied 33 pediatric patients who underwent craniotomies for fenestration of progressive multiloculated hydrocephalus between 1989 and 2003. In 20 of 33 patients, hydrocephalus was attributed to intraventricular hemorrhage associated with prematurity. Twenty-three of 33 patients had previous central nervous system infections. Craniotomy was typically performed via a posterior parietal approach. Communication between bilateral supratentorial loculated compartments and posterior fossa compartments was achieved. Surgical and neurological outcomes were assessed. RESULTS: Fenestration of loculated CSF spaces was performed successfully in all patients. No new neurological deficits were noted after surgery, and no patients required intraoperative blood transfusions. CSF infections within 3 months after surgery occurred in 4 of 33 patients. Over a median follow-up period of 3.7 years (range, 1.5 mo to 8.7 yr), 19 of 33 patients required additional fenestration procedures. The number of repeat fenestration procedures ranged from one to six, and a total of 47 additional fenestrations were performed in these 19 patients. The majority of patients (n = 25) ultimately required shunt systems with only one ventricular catheter. The neurological status of these patients was extremely poor both before and after surgery. Twenty-nine of 33 patients were severely delayed, and four were mildly delayed. CONCLUSION: Fenestration of multiloculated CSF compartments can enable most patients to function with a single ventricular catheter shunt system. Neurological status remains poor in this patient population.

Catheterization↗
PubMed2005

Synchronous multicentric pleomorphic xanthoastrocytoma: case report.

OBJECTIVE AND IMPORTANCE: Pleomorphic xanthoastrocytoma (PXA) is a rare, low-grade astrocytoma of adolescence. Relatively favorable outcomes have been achieved with complete surgical resection. However, few data exist regarding the treatment of recurrent, deep-seated, or multicentric lesions. We report the first case to our knowledge of synchronous multicentric PXA and discuss the related therapeutic challenges. CLINICAL PRESENTATION: A 13-year-old Hispanic girl presented with a 1-year history of progressive headaches, polyuria, and generalized fatigue. Findings from the neurological examination were notable only for the presence of papilledema. Results of laboratory studies revealed diabetes insipidus and hypothyroidism. The magnetic resonance imaging study revealed numerous nodular, homogeneously enhancing lesions, approximately 1 cm in size, scattered throughout both cerebral hemispheres. INTERVENTION: A right frontal craniotomy was performed for excisional biopsy of a superficial lesion beneath the coronal suture. Results of the histological examination were consistent with a diagnosis of PXA. The patient was treated with whole-brain radiation of 3600 cGy, with additional intensity-modulated boosts to the enhancing lesions of 1440 cGy. Three years after treatment, the patient remains neurologically nonfocal and shows no evidence of disease progression. Surgical intervention will be considered if accessible lesions progress in size on later imaging studies. CONCLUSION: Synchronous multicentric PXA presents unique challenges in that gross total resection would impose significant surgical morbidity; histological homogeneity among the lesions cannot be confirmed; and the well-described potential for anaplastic transformation may be increased with multiple lesions. The optimal treatment for patients with this rare and challenging diagnosis awaits further study.

Adolescent↗
PubMed2005

Chemical analysis of fluid obtained from intracranial arachnoid cysts in pediatric patients.

OBJECT: The authors analyzed the chemical composition of intracranial arachnoid cyst fluid to gain greater understanding of potential causes of cyst growth. METHODS: The authors studied 54 pediatric patients who underwent craniotomies for arachnoid cyst fenestration. Cyst fluid was analyzed and results were compared with expected values (EVs) for cerebrospinal fluid (CSF). The arachnoid cyst fluid values were as follows: protein (median 37 mg/dl, mean 178.2 mg/dl, and EV 25.6 mg/dl), osmolality (median 284 mOsm/kg, mean 285.5 mOsm/kg, and EV 287.2 mOsm/kg), potassium (median 2.6 mEq/L, mean 2.68 mEq/L, and EV 2.88 mEq/L), sodium (median 140 mEq/L, mean 142.2 mEq/L, and EV 143.3 mEq/L), and chloride (median 122 mEq/L, mean 120.77 mEq/L, and EV 120.3 mEq/L). Median glucose was 51 mg/dl (range 26-98 mg/dl). The median white blood cell count in cyst fluid was 1/mm3, and the median red blood cell (RBC) count was 1.5/mm3. All Gram stains and cultures were negative. No statistically significant correlations were found between arachnoid cyst fluid protein level and elevated RBC count, patient age, or the subsequent need for a shunt. Elevated RBC count in cyst fluid was also not associated with the subsequent need for a shunt. CONCLUSIONS: Fluid from arachnoid cysts has a chemical composition similar to that of CSF, but some of them have significantly elevated protein levels. The authors hypothesize that elevated protein content may contribute to arachnoid cyst expansion in some patients.

Adolescent↗
PubMed2005

MRI tracer study of the cerebrospinal fluid drainage pathway in normal and hydrocephalic guinea pig brain.

OBJECTIVE: Using magnetic resonance imaging (MRI), sequential information regarding the dynamic movement of the cerebrospinal fluid (CSF) from the subarachnoid space and the ventricles to the drainage pathway in response to the CSF pressure was obtained in guinea pigs. In this study, a new mechanical hydrocephalus model in a guinea pig was developed to investigate the CSF kinetics in an acute hydrocephalic brain. MATERIALS AND METHODS: A total of 18 adult male guinea pigs were studied. In the ventricular injection group, The CSF in the lateral and third ventricles was isolated by inserting a polyethylene tube with a cotton ball into the aqueduct of Sylvius. By infusing artificial CSF through this tubing acute ventriculomegaly was created. In the subarachnoid injection group, a polyethylene tube was placed at the cisterna magna. Using MRI with gadoteridol as a tracer, the movement of CSF from the subarachnoid space and dilated ventricles was monitored at various pressures. The CSF drainage pathway from the subarachnoid space in the hydrocephalic condition was examined and compared with the CSF drainage pathway in normal condition. RESULTS: Gadoteridol cleared from the lateral and third ventricles and reached the nasal mucosa via brain parenchyma; the movement was proportional to the CSF pressure. Gadoteridol from the subarachnoid space also reached the nasal mucosa and periorbital region in a similar manner. However, it was not observed to reach either over the convexity of the brain or adjacent to the superior sagittal sinus.

Animals↗
PubMed2004

High rates of neurological improvement following severe traumatic pediatric spinal cord injury.

STUDY DESIGN: Retrospective single-center study OBJECTIVES: To determine the long-term outcome of pediatric spinal cord injuries SUMMARY OF BACKGROUND DATA: Spinal cord injuries are uncommon events in the pediatric population. In the few large series reported in the literature, recovery of neurologic function was demonstrated after mild injuries but was rare after severe injuries. METHODS: A total of 4,876 cases of pediatric trauma treated at the Children's Hospital of Los Angeles over a 9-year period (1993-2001) were reviewed. During the study period, 91 cases of spinal cord or spinal column injury were identified, and 30 cases involving a spinal cord injury were identified. Cauda equina injuries were excluded. Seven craniocervical, 12 cervical, 5 thoracic, and 6 thoracolumbar cases were identified. There were 6 cases of spinal cord injury without radiographic abnormality. Eight of the 30 patients received methylprednisolone at the time of admission. Follow-up ranged from 2 to 54 (mean = 19) months. RESULTS: Twenty patients presented with complete injuries (ASIA grade A). Of these, 7 died, 7 had no neurologic recovery, and 6 experienced neurologic improvement. Five of these six eventually became ambulatory with functional gains occurring over a 4- to 50-week period. None of these 5 patients was found to have spinal cord injury without radiographic abnormality. Of the remaining 10 patients (grades B-D), 8 experienced improvements in neurologic function. Cervical dislocation injuries were associated with a low likelihood of neurologic improvement and atlanto-occipital injuries were associated with early death. CONCLUSIONS: Recovery of neurologic function following severe traumatic spinal cord injury occurs with a significantly greater incidence in children than adults, and these improvements can occur over a prolonged postinjury period.

Accidents, Traffic↗
PubMed2004

Pediatric sacral fractures.

STUDY DESIGN: Retrospective review. OBJECTIVES: To examine the epidemiologic, anatomic, mechanistic, and outcome characteristics in pediatric patients with sacral fractures and to look for correlation with the adult literature regarding sacral fractures and previous classification systems. SUMMARY OF BACKGROUND DATA: A review of the current literature reveals no systematic attempts to apply the results of studies of sacral fractures in adults to those in the pediatric population. METHODS: We reviewed all 4876 cases of pediatric trauma at 1 children's hospital over a 7-year period. Eight children had documented sacral fractures. Their charts were reviewed, and follow-up interviews were conducted. RESULTS: All patients suffered either motor vehicle accidents or falls from height. Three patients' injuries were confined to the pelvic rim including the sacrum. Mean follow-up was 38 months. Six patients had Denis Zone I injuries, 1 patient had a Zone II injury (no neurologic deficits in either category), and 1 patient had a Zone III injury with significant neurologic injury. Only this patient required surgical intervention. Long-term recovery was good in those without comorbid injuries. CONCLUSIONS: Pediatric sacral fractures are rare (0.16% of pediatric trauma). As is the case in adults, most fractures are not associated with neurologic injury. Diagnosing pediatric sacral fractures requires high clinical suspicion and thorough radiographic evaluation. Correlation of neurologic injury with certain fracture types may be possible, but will require larger studies to be confirmed.

Adolescent↗
PubMed2004

Iatrogenic intraspinal epidermoid tumor: two cases and a review of the literature.

STUDY DESIGN: Two cases of patients whom intraspinal epidermoid tumors presented and were successfully removed 6 years after neonatal lumbar puncture are reported. OBJECTIVE: To describe the presentation of this type of spinal tumor and strategies for diagnosis and treatment. SUMMARY OF BACKGROUND DATA: Cells iatrogenically implanted into the spinal canal during lumbar puncture can slowly grow until symptomatic. Diagnosis can be difficult and is often delayed. MRI appears to offer some advantages in diagnosis provided that gadolinium is used. Treatment is by surgical excision. METHODS: The first patient, a 6-year-old boy, presented with severe episodic hip pain of unknown etiology. MRI of the lumbar spine revealed a 1-cm epidermoid at L1-L2. The second child, a 6-year-old girl, presented with low back pain and dragging of the feet. MRI revealed a mass at L3. RESULTS: In both cases, complete excision via lumbar laminectomy was performed. Both patients were asymptomatic at the 1-year follow-up with resolution of preoperative weakness. CONCLUSIONS: This study highlights an uncommon but not rare tumor that may present to the spine specialist in a variety of ways. The diagnosis is often delayed. The advent of MRI has improved the ease and accuracy of diagnosis. Complete excision is usually possible and is curative.

Carcinoma, Squamous Cell↗
PubMed2004

Atypical teratoid/rhabdoid tumor: an unusual presentation.

Atypical teratoid/ rhabdoid tumor (AT/RT) of the central nervous system is a rare, highly aggressive malignancy of infancy. Although it is reported infrequently in the literature, it has often been histologically confused with a primitive neuroectodermal tumor (PNET)/medulloblastoma (MB) but has a much worse prognosis. We present an infant with two AT/RT tumors, one suprasellar in location and the other within the vermis without evidence of tumor elsewhere. What makes this case unusual is that there were two separate lesions in different cranial compartments, with no evidence of subarachnoid seeding. In addition, the lesions had different magnetic resonance imaging (MRI) characteristics even though they were histologically the same.

Female↗
PubMed2004

Unusual presentations of cerebral solitary fibrous tumors: report of four cases.

OBJECTIVE AND IMPORTANCE: Four rare cases of central nervous system solitary fibrous tumors (C-SoFTs) are described. This tumor has not previously been reported in children or in deep cortical structures. Three of these tumors occurred in the posterior fossa. Only four cases in the posterior fossa have been described previously. Nine years after its debulking from the posterior fossa, one tumor disseminated to the spine, lung, and liver. Only one such aggressive C-SoFT has been described previously. CLINICAL PRESENTATION: A 7-year-old child had had 1 year of right-sided weakness at presentation. Magnetic resonance imaging scans revealed a left basal ganglia lesion. A 49-year-old woman and a 30-year-old man presented after experiencing headaches for months. Magnetic resonance imaging scans in these patients revealed a tumor in the fourth ventricle and right jugular foramen, respectively. A 55-year-old man had spinal, liver, and lung dissemination of a previous posterior fossa tumor at presentation. INTERVENTION AND TECHNIQUE: All four patients underwent craniotomy for resection or subtotal removal of the tumor. Intraoperative observations noted solid well-encapsulated tumors. Immunohistochemistry confirmed C-SoFTs in all four cases. CONCLUSION: C-SoFTs are rare central nervous system, typically dural-based, tumors. They frequently are overlooked in the differential diagnosis of solid central nervous system tumors. Our findings suggest that these tumors can occur at any age and in most locations, regardless of proximity to the meninges (basal ganglia and ventricle), suggesting that the cells of origin are not meningothelial, but rather the mesenchyme of the cerebral vasculature. T1- and T2-weighted magnetic resonance imaging was notable for areas of hypointensity and of hyperintensity best described as patchy or a ying-yang appearance in all cases. Delayed extracranial metastasis may be noted.

Adult↗
PubMed2004

A method to accurately inject tumor cells into the caudate/putamen nuclei of the mouse brain.

OBJECTIVE: To improve currently used techniques to implant tumor cells into the parenchyma of the mouse brain. MATERIALS AND METHODS: The stereotactic injection of 0.5 to 5 microl of indigo carmine over 5 to 40 minutes into the caudate/putamen nuclei of the mouse was done followed by sacrifice and examination of the brain injection site. 1 microl containing 10(5) U87MG glioma cells were stereotactically implanted into the caudate/ putamen nuclei over 20 minutes. The animals were sacrificed from one hour to 63 days after implantation and the brain examined and tumor size measured. RESULTS: An injection of 1 microl of indigo carmine over 20 minutes produced a spherical deposit of dye within the caudate/putamen nuclei. Larger volumes of indigo carmine or shorter injection times resulted in dye spreading along the injection tract or into the ventricles or subarachnoid space. Using the results of the dye studies, the same parameters were used to successfully inject and confine the glioma cells to the caudate/putamen nuclei in 30 of 32 mice. No tumor was found in 2 animals and appears to be explained by obstruction of the injection cannula. The tumor cells appeared viable an hour after injection. However by day three, considerable necrosis of tumor cells were noted, the effects of which resolved by day five. On day six, the injection site was comparable to that at one hour. In the early phase, until the fifth week, tumor volume doubling time was ten days while afterward it was only five days. CONCLUSION: The technique described allows the highly accurate and reproducible introduction of a given number of cells into a specific area of the mouse brain. This should reduce the intragroup variability, be it control or therapeutic, allowing better assessment of outcome with fewer number of mice.

Animals↗
PubMed2003

Magnetic resonance spectroscopy of atypical diffuse pontine masses.

OBJECT: Diffuse pontine gliomas in children carry a dismal prognosis, with a mean survival of less than 1 year despite therapy. The diagnosis is based on the characteristic changes demonstrated on traditional magnetic resonance (MR) imaging. A few typically MR imaging-appearing pontine masses, however, do not behave in the expected fashion, which calls the original diagnosis into question. METHODS: The authors conducted a retrospective review of data obtained in 42 children (age 6 months-13 years) in whom diffuse pontine glioma had been diagnosed at their institution. Five of these patients (12%) survived longer than expected (> 18 months). There were no differences in these patients in terms of demographics, presentation, traditional imaging findings, or treatment compared with the group as a whole. Magnetic resonance spectroscopy, however, demonstrated two distinct patterns not seen in typical diffuse pontine gliomas. In two patients elevated lipid and lactate levels were shown, with decreased levels of choline, myoinositol, and N-acetyl-aspartate (NAA). In the other patients strikingly elevated choline/creatinine ratios and myoinositol levels were observed in comparison with typical pontine tumors. CONCLUSIONS: These MR spectroscopy patterns demonstrated in this retrospective study seem to convey prognostic information and may lead to an expansion of this diagnostic tool.

Adolescent↗