Value and limitations of diffusion-weighted imaging in grading and diagnosis of pediatric posterior fossa tumors.

DWI reportedly accurately differentiates pediatric posterior fossa tumors, but anecdotal experience suggests limitations. In 3 years, medulloblastoma and JPA were differentiated by DWI alone in 23/26 cases (88%). Ependymoma (n = 5) could not be reliably differentiated from medulloblastoma or JPA. A trend toward increased diffusion restriction in higher grade tumors (1/14 grade I, 7%; 9/12 grade IV, 75%) had too much overlap to predict the grade of individual cases. The overlap in ADC between tumor types appeared partly due to technical factors (in small, heterogeneous, calcific, or hemorrhagic tumors) but also likely reflected true histologic variability, given that our 3 overlap cases included a desmoplastic medulloblastoma, an anaplastic ependymoma, and a JPA with restricted diffusion in its nodule. Simple structural features (macrocystic tumor, location off midline) aided in distinguishing JPA from the other tumors in these cases.

Microlissencephaly with cardiac, spinal and urogenital defects.

We describe two children with a brain defect similar to that described as 'microlissencephaly', as defined in Barkovich et aL [(1998) Neuroped 29: 113-119]. Concomitant malformations (cardiac, spinal, urogenital) may represent components of a wider syndrome complex; alternatively, or additionally, there may have been a valproate teratogenic effect. The inheritance is likely to be autosomal recessive, although X-linkage cannot be excluded.

Near-total absence of the cerebellum.

We report five cases of near-total absence of the cerebellum with accompanying pontine hypoplasia. The cerebellar remnant in each case comprised only antero-superior masses, the posterior fossa being otherwise fluid filled. Three of these patients, two teenagers and an infant, presented a fairly consistent clinical and neuroradiological phenotype, and a few similar cases are recorded in the literature. The cerebellar remnant was irregular and asymmetrical, and no ventral pontine prominence was discernible. In at least the older two, cerebellar motor functions were not greatly compromised, and intellectual handicap was of a mild degree. We propose that these cases represent a distinct entity of "near-total absence of the cerebellum with flat ventral pons, and relatively mild clinical affection". All cases have been sporadic, implying that the risk of recurrence within a family may be low. Quite different clinical pictures, of considerably greater severity, are demonstrated in the remaining two cases. One had pontocerebellar hypoplasia type 2, while the other had a complex cerebellar and cerebral malformation.

Clinical and neuroradiologic features of acute disseminated encephalomyelitis in children.

OBJECTIVE: To identify the clinical and neuroradiologic features of acute disseminated encephalomyelitis (ADEM) in childhood. METHODS: A retrospective review was conducted of the medical records and MRI of children who presented to the Royal Children's Hospital in Melbourne with ADEM between January 1993 and December 1998. RESULTS: Of the 31 patients included in this study, 22 (71%) experienced a prodromal illness. Two patients (6%) had received hepatitis B vaccine 3 to 6 weeks before developing their illness. Symptoms and signs typically evolved over several days. Ataxia was the most common presenting feature, occurring in 20 patients (65%). MRI findings were variable, but lesions were most commonly seen bilaterally and asymmetrically in the frontal and parietal lobes. The authors found a high incidence of the corpus callosal and periventricular changes more typically associated with MS, but they also found a high rate of deep gray matter involvement (61% of patients). The use of high-dose IV methylprednisolone was usually associated with rapid recovery. Eighty-one percent of patients recovered completely, with only mild sequelae recorded in the remaining children. CONCLUSION: In the absence of a biological marker, the distinction between ADEM and MS cannot be made with certainty at the time of first presentation, but the authors suggest that a viral prodrome, early-onset ataxia, high lesion load on MRI, involvement of the deep gray matter, and absence of oligoclonal bands are more indicative of ADEM.

Upper cervical spinal cord injury in neonates: the use of magnetic resonance imaging.

Neonatal upper cervical spinal cord injury is associated with rotational forceps delivery and presents with quadriparesis and diaphragmatic paralysis. The underlying pathology determines neurologic outcome but is difficult to assess clinically or with simple radiographic techniques. We report 4 cases in which early magnetic resonance imaging demonstrated the extent and severity of the injury and guided management.

Syntelencephaly presenting with spastic diplegia.

Two children with syntelencephaly presented with the predominant clinical picture of spastic diplegia. Brain scanning showed deficient formation of the interhemispheric fissure with fusion of occipital and parietal lobes, and an infolding and protrusion of occipital cortex into the telencephalic ventricle. The fusion extended further posteriorly than the cases of "middle interhemispheric fusion" thus far reported. One 7-year old has poor language development, while the other is regarded, at her present age of 3 years, as being cognitively within the normal range.

Recurrent myelinoclastic diffuse sclerosis: a case report of a child with Schilder's variant of multiple sclerosis.

Myelinoclastic diffuse sclerosis (MDS, Schilder's disease) is a rare CNS demyelinating disorder affecting mainly children and usually presenting as an intracranial mass lesion. We report the first case of recurrent intracranial MDS where the third episode of demyelination involved the cervical spinal cord. This may represent a subset of the disease, which should be considered as Schilder's variant (childhood form) of multiple sclerosis.

Clinical and imaging features of cortical malformations in childhood.

OBJECTIVE: To determine the types, relative frequencies, clinical features, and MRI characteristics of malformations of cortical development (MCD) occurring in a cohort of children referred to a tertiary pediatric center. METHODS: Original MR images were reviewed by two investigators, who were blinded to clinical details, to determine the elemental imaging features of each malformation and to label these malformations according to an existing system of classification. Clinical information was collected by a review of hospital records. RESULTS: A total of 109 children with MCD were identified. There were 58 boys and 51 girls, age 8 days to 18 years at initial imaging (mean age, 5 years). Seizures were present in 75%, developmental delay or intellectual disability in 68%, abnormal neurologic findings in 48%, and congenital anomalies apart from the CNS malformation in 18%. The main malformations identified were heterotopic gray matter (19%), cortical tubers (17%), focal cortical dysplasia (16%), polymicrogyria (16%), agyria/pachygyria (15%), schizencephaly/cleft (5%), transmantle dysplasia (5%), and hemimegalencephaly (4%). Eight patients had features of more than one malformation. Most lesions were multilobar (47%), with the frontal lobe being the most common lobe involved (78%). A total of 68% of patients had other cerebral malformations including ventricular dilatation or dysmorphism (46%) and abnormalities of the corpus callosum (29%). CONCLUSIONS: This study illustrates the spectrum of MCD in a pediatric cohort and highlights some of the differences between pediatric and adult patients. Patients with MCD presenting in childhood have a wider spectrum of malformations and more varied, often more severe, clinical manifestations. The lesions are frequently multifocal or generalized and many are associated with noncortical developmental brain anomalies.

Congenital muscular dystrophy, white-matter abnormalities, and neuronal migration disorders: the expanding concept.

The congenital muscular dystrophies are a heterogeneous, recessively inherited group of disorders that have been subclassified on the basis of clinical central nervous system involvement. We report two children with "pure" congenital muscular dystrophy, one merosin negative and one merosin positive with extensive white matter and occipital cortical neuromigration abnormalities on magnetic resonance imaging (MRI). The first patient (merosin-negative congenital muscular dystrophy) presented with hypotonia and weakness in the neonatal period and subsequently was found to have a leukoencephalopathy and occipital cortical dysplasia on magnetic resonance imaging. The second patient presented with developmental delay without definite weakness. Initial investigations revealed a leukoencephalopathy and cortical dysplasia, but the patient subsequently was shown to have merosin-positive congenital muscular dystrophy. These patients illustrate that white-matter changes are not specific for merosin-negative congenital muscular dystrophy alone and that extensive cortical abnormality can be found in both groups of patients. In addition, our second patient illustrates a nonmuscular mode of congenital muscular dystrophy presentation that should be considered in patients with a "nonprogressive leukodystrophy."

Paroxysmal tonic upgaze: a reappraisal of outcome.

Paroxysmal tonic upgaze (PTU) of childhood is a distinctive neuro-ophthalmological syndrome of unknown etiology and pathogenesis that is characterized by episodes of sustained upward deviation of the eyes, often with incomplete downward saccades on attempted downgaze. It is generally regarded as having a benign outcome. We observed 16 children with PTU, from 10 months to 11 years from onset (mean, 5.4 years), to study the natural history and possible etiology. Five cases were from two unrelated families. Onset of PTU occurred either during or after an intercurrent infection or vaccination in 5 children. No antecedent was identifiable in the rest. PTU had completely resolved in 10 children (62%) (mean age at offset, 2.5 years), whereas 2 children intermittently manifest a modified form of the disorder. At follow-up, 11 children (69%) had developmental delay, intellectual disability, or language delay and 9 (56%) had ocular motility problems other than PTU. Only 3 children (19%) had normal development and neurological findings. PTU is a heterogeneous syndrome with respect to associations and outcome and may simply be an age-dependent manifestation of a variety of disorders affecting corticomesencephalic control of vertical eye movement. This disorder may be an early sign of more widespread neurological dysfunction.

Stroke and fibromuscular dysplasia: confirmation by renal magnetic resonance angiography.

Childhood stroke is uncommon and may require extensive evaluation to elucidate an underlying cause. A 9-year-old boy had clinical and magnetic resonance imaging (MRI) features of an ischemic event in the left middle cerebral artery territory. Magnetic resonance angiography (MRA) revealed beading of the left middle cerebral artery, consistent with irregular blood flow secondary to turbulence or luminal narrowing. Conventional angiography of the cerebral vessels confirmed the findings of cerebral MRA and raised further the suspicion of fibromuscular dysplasia (FMD). MRA of the renal vessels was subsequently performed, revealing beading of the left renal artery and confirming the diagnosis of FMD. MRA, a rapid and less invasive technique associated with far less morbidity and mortality as compared with conventional angiography, may prove to be as sensitive as conventional angiography in detecting the changes of FMD. MRA of the renal arteries should be performed with initial cranial MRI and MRA in children who present with cerebral infarction of possible vascular origin. This may obviate the need to perform further investigations and may make early diagnosis possible at the first MRI scan and under a single general anesthetic.

Systematic approach to the management of the Type II diabetic patient: case presentation.

Recently there has been a trend toward more aggressive management of people with diabetes. This stems from the conclusive clinical data that substantiate the benefit of tight glycemic control. It is clear that achieving near normoglycemia in people with diabetes will prevent and slow the progression of the microvascular complications and reduce the risk of the macrovascular complications. Clinicians now have multiple agents with differing mechanisms and sites of action allowing them to individualize the medication regimen and move toward normalizing the blood glucose levels. The following case is representative of a typical patient with Type II diabetes. This patient presents with multiple disease states and various treatment issues that must be addressed. An in-depth evaluation of the patient case is presented along with recommendations for drug therapy modifications.

Ventriculus terminalis of the conus medullaris: MR findings in children.

PURPOSE: To determine the appearance of the ventriculus terminalis of the conus medullaris and the frequency with which it is seen on MR. METHODS: Four hundred eighteen normal spine MR examinations were reviewed. RESULTS: Eleven (2.6%) of 418 children, all younger than 5 years of age, demonstrated an ovoid, nonenhancing, smooth dilation of the central canal within the conus medullaris. Averaged volume of the oblate spheroid was 0.18 cm3. Fluid within the cavity behaved as cerebrospinal fluid on all pulse sequences, and there was no abnormal signal in the cord tissue surrounding the cavity. CONCLUSION: Asymptomatic localized dilatation of the ventriculus terminalis is a normal developmental phenomenon that can be seen on MR.

Bronchiectasis in children.

Bronchiectasis (BR) is a descriptive term for abnormal, irreversibly dilated, and often thick walled bronchi, usually associated with inflammation. Causes are varied but include cystic fibrosis, aspiration, post infectious airway obstruction, immune abnormalities, immotile cilia, posttransplantation states, and congenital bronchial lesions. Although BR is uncommon in children, it causes significant mortality when present. Following a period of presumed decline due to antibiotics and vaccines, BR may increase in prevalence because of AIDS, organ transplantation complications, and changing patterns of childhood immunization. As with adults, high resolution CT (HRCT) is the most useful imaging tool for diagnosis and evaluation of bronchiectasis in children.

Pediatric craniospinal spiral CT: current applications and future potential.

Spiral CT has a definite role in pediatric neuroimaging. It is fast and offers relatively artifact-free planar and three-dimensional reconstructions. It also provides dynamic vascular phase imaging, a significant decrease in radiation and contrast media requirements, and a potential decrease in sedation while still producing good diagnostic image quality. The complete role of spiral CT angiography in pediatric neuroimaging is, as yet, incompletely explored, but potentially is very useful in the clinical setting of acute head and spine trauma.

Documentation of clinical interactions: quality of care issues and economic considerations in critical care pharmacy.

Pharmacists employed in the critical care area in a 350 bed, community-based, Class II trauma facility demonstrated cost savings through documentation of clinical interactions. Data collection took place between January 1, 1986 and December 31, 1986. Four areas of potential cost savings to the hospital were identified: 1) interactions that resulted in drug cost avoidance of $26,580 per year; 2) detection of excessive doses, toxic serum concentrations and electrolyte imbalances resulting in maximizing quality drug therapy; 3) unnecessary or inappropriate laboratory tests, which avoided $3930 in patient charges due to 80 fewer tests; 4) reduced inventory from the critical care area allowing $5209 in medication to be relocated. Under current prospective reimbursement programs, cost containment and quality care are of primary concern for pharmacy departments. The presence of a critical care satellite staffed by qualified pharmacists can provide these measures.

Pharmacist-directed heparin therapy using a standard dosing and monitoring protocol.

Use of a protocol for pharmacist determination of heparin sodium dosages administered by continuous i.v. infusion was evaluated by retrospective chart review in a California hospital. Charts of adult medical-surgical patients who received heparin infusions between June 1982 and December 1983 were reviewed for the following information: patient sex, age, and reason for receiving heparin; times, dates, numbers, and values of coagulation tests before and during heparin therapy; times, dates, and values of prothrombin time determinations during conversion to warfarin therapy; and times, number, and costs of heparin infusions. Charts were divided into two groups: those of patients for whom physicians prescribed heparin doses empirically and those of patients for whom physicians requested heparin dosing by the pharmacy department. Data were evaluated for 62 patients in the physician-dosed group and 26 patients in the pharmacy protocol group. Pulmonary embolism was the reason for heparin therapy in 34% of the physician-dosed patients and only 15% of the pharmacist-dosed patients. Pharmacists using the protocol ordered fewer anticoagulation tests and fewer heparin infusions per patient. Time from the start of heparin therapy to therapeutic anticoagulation was shorter in patients whose heparin dose was determined by the protocol, and values in the therapeutic range were achieved in a greater percentage of these patients than in the empirically dosed patients. Pharmacists using a standard dosing protocol effectively initiated and maintained heparin therapy that compared favorably with physician-dosed empiric therapy.

Achieving pharmacist proficiency in pharmacokinetic dosage adjustments.

A pharmacokinetics training and certification program for staff pharmacists in a community hospital is described. A pharmacokinetics committee consisting of six pharmacists with extensive clinical experience in pharmacokinetics was formed to implement the program. A self-teaching module incorporating basic pharmacokinetic concepts and sample problems was developed. Specific guidelines for calculating dosages of the aminoglycosides and theophylline were also developed, as were indications for the appropriate ordering and serum sampling of these drugs. These guidelines were used in the didactic training of pharmacists, and their knowledge of this information was evaluated by written examinations. Pharmacists were also required to calculate drug dosages for patients in the hospital. These pharmacokinetics calculations were evaluated by the pharmacokinetics committee at periodic meetings. Of the 12 pharmacists included in the training program initially, 9 completed the entire training and certification process. All new pharmacists are now required to obtain certification in pharmacokinetics; yearly recertification of all pharmacists is obtained by participation in patient case presentations involving calculation of drug dosages. This pharmacokinetics training program ensures a standard level of competency among staff pharmacists and may increase physicians' reliance on pharmacists for adjusting drug dosages.