Nonaccidental pediatric head injury: diffusion-weighted imaging findings

OBJECTIVE

Diffusion-weighted imaging (DWI) reveals nonhemorrhagic posttraumatic infarction hours to days before conventional computed tomographic scanning or magnetic resonance imaging (MRI). We evaluated the diagnostic utility of DWI in children with nonaccidental head trauma.

METHODS

The medical records and imaging examinations obtained between January 1998 and May 2000 for all children less than 2 years of age with presumed or suspected nonaccidental head injury were reviewed retrospectively. Twenty children who had undergone DWI within 5 days of presentation were included in the study. Computed tomographic scans, conventional MRI sequences, and DWI combined with apparent diffusion coefficient (ADC) maps were evaluated.

RESULTS

Eleven girls and nine boys (median age, 5 mo) were studied. Eighteen children had presumed nonaccidental head trauma, and two children had suspected nonaccidental head trauma. Of the 18 children with presumed nonaccidental trauma, 16 (89%) demonstrated abnormalities on DWI/ADC, as compared with neither of the two children with suspected nonaccidental trauma. In 13 (81%) of 16 positive cases, DWI revealed more extensive brain injury than was demonstrated on conventional MRI sequences or showed injuries not observed on conventional MRI. DWI combined with ADC maps allowed better delineation of the extent of white matter injury. DWI/ADC abnormalities in the nonaccidental head-injured children were likely to involve posterior aspects of the cerebral hemispheres, with relative sparing of the frontal and temporal poles. Severity on DWI correlated significantly with poor outcome (P < 0.005).

CONCLUSION

DWI has broad applications in the early detection of infarction in children with nonaccidental head injury and enhances the sensitivity of conventional MRI. In the patients in this study, early DWI provided an indicator of severity that was more complete than any other imaging modality. The use of DWI may help to identify children at high risk for poor outcome and to guide management decisions.

Social information processing and magnetic resonance imaging in children with sickle cell disease

OBJECTIVE

To examine social information processing, social skills, and adjustment difficulties in children with sickle cell disease (SCD) as rated by caregivers, teachers, and the children themselves. Children were classified in two groups: cerebral vascular accidents (CVA) (n = 21) or without central nervous system (CNS) pathology (n = 20) on magnetic resonance imaging (MRI). Both groups had HbSS SCD. We compared these two groups and a third group of 11 children who had a milder type of SCD (HbSC).

METHODS

Participants referred for evaluation of learning and behavior problems were administered MRIs to ascertain the presence of pathology and a series of measures designed to assess nonverbal emotional decoding abilities and ratings of social emotional functioning.

RESULTS

Children with CVA displayed more errors on tasks of facial and vocal emotional decoding than did comparison controls without CVA.

CONCLUSIONS

Acquired neurological impairments in children with SCD seemed to be associated with difficulties in the decoding of emotions of other children and adults. We recommend that future research integrate neuropsychological and psychosocial research programs for pediatric chronic illness groups.

Imaging of head trauma in infancy and childhood

Neurologic trauma is one of the most common and challenging problems encountered in the pediatric emergency setting. Early and accurate diagnosis is essential to minimize morbidity and mortality. The primary goal of the neuroimager in the acute setting is to provide rapid diagnosis, to monitor the development of complications, and to aid in the determination of prognosis. Unique features of the immature brain and skull influence the patterns and types of injuries observed. It is incumbent on the radiologist to understand these features as an aid to diagnosis. Further, the radiologist must be aware of the pathophysiology and appearance of nonaccidental trauma to ensure recognition of this devastating problem. Lastly, the radiologic tools available, their appropriate use, and their limitations should be understood by the entire trauma team to provide cost-effective and timely care. This article summarizes the pathophysiology and current imaging of neurotrauma in the pediatric population, including trauma, nonaccidental trauma, accidental anoxic injury, and birth injury.

Sinus pericranii. A case report

A 7-month-old male presented with a 2 X 3 cm soft tissue mass overlying the right mastoid bone. An underlying bony defect was palpable. Plain skull films, CT scan and cerebral arteriogram showed the classic radiologic findings of a sinus pericranii. This rare vascular anomaly is briefly discussed.

Intracranial cystic malignant fibrous histiocytoma in a child: sonographic and CT findings

Primary intracranial cystic malignant fibrous histiocytoma (MFH) is an extremely rare tumor with only 15 cases reported. Only three cases of cystic intracranial MFH are found in the literature. We present the sonographic and CT findings in a child with such a lesion.

Melanotic neuroectodermal tumor of infancy. MR findings and a review of the literature

Melanotic neuroectodermal tumor of infancy is an uncommon neoplasm occurring primarily in the child one year or less in age. Difficulty in deciding the cellular origin of this tumor has led to numerous names, including congenital melanocarcinoma, melanotic epithelial odontoma, melanotic ameloblastoma, and retinal anlage tumor, to list a few. Electron microscopy and histochemical studies, however, have now established the neural crest as the most likely origin. The most frequent site of occurrence is the maxilla followed by the skull, the brain and the mandible. The genital organs are the most frequent extracranial site. Within the skull, there is a predilection for the anterior fontanel. The following is a case report of a young child with melanotic neuroectodermal tumor of infancy arising at the anterior fontanel. Included is a discussion of magnetic resonance (MR) findings, which to our knowledge, have not been previously reported in this tumor.

Neurocognitive functioning and magnetic resonance imaging in children with sickle cell disease

OBJECTIVE

To examine neurocognitive functioning in children classified with overt cerebral vascular accidents (CVAs), silent infarcts, or without central nervous system (CNS) pathology on magnetic resonance imaging.

METHODS

Participants were 63 children and adolescents with sickle cell disease (SCD).

RESULTS

Children with overt CVAs and silent infarcts differed from their peers without CNS pathology on measures of attention and executive functioning.

CONCLUSIONS

We consider these deficits the result of the high frequency of frontal lobe deficits incurred by children with SCD. Recommendations include the use of tests designed to measure attention and executive functioning as a way of screening children with SCD for possible CNS pathology. We also suggest that future research examine the mechanism underlying frontal lobe involvement for individuals with SCD.

Bone marrow transplantation for infantile ceramidase deficiency (Farber disease)

Infantile ceramidase deficiency (Farber disease) is an uncommon, progressive lysosomal storage disease characterized by multiple ceramide-containing nodules (lipogranulomata) in the subcutaneous tissue and upper aerodigestive tract, painful periarticular swelling, psychomotor retardation, and varying degrees of ocular, pulmonary or hepatic involvement. Management of Farber disease has been limited to symptomatic supportive care, and few affected infants survive beyond 5 years of age. We performed an allogeneic bone marrow transplant (BMT) from an HLA-identical heterozygous sister in a 9.5-month-old female with minimally symptomatic Farber disease who received a pre-transplant regimen of busulfan and cyclophosphamide. Ceramidase activity in peripheral blood leukocytes increased from 6% before transplant to 44% (donor heterozygote level) by 6 weeks after BMT. By 2 months after transplant, the patient's subcutaneous lipogranulomata, pain on joint motion, and hoarseness had resolved. Despite modest gains in cognitive and language development, hypotonia and delayed motor skills persisted. Gradual loss of circulating donor cells with autologous hematopoietic recovery occurred; VNTR analyses showed 50% donor DNA in peripheral blood cells at 8.5 months after BMT and only 1% at 21 months after transplant. Interestingly, leukocyte ceramidase activity consistently remained in the heterozygous range despite attrition of donor cells in peripheral blood. This novel observation indicates ongoing hydrolase production by non-circulating donor cells, possibly in the mononuclear phagocytic system, and uptake by recipient leukocytes. Although lipogranulomata and hoarseness did not recur, the patient's neurological and neurocognitive status progressively declined. She died 28 months after BMT (age 37.5 months) with pulmonary insufficiency caused by recurrent aspiration pneumonias. Allogeneic BMT improves the peripheral manifestations of infantile ceramidase deficiency, but may not prevent the progressive neurological deterioration, even when carried out in minimally symptomatic patients.

Analysis and pharmacokinetics of quetiapine and two metabolites in human plasma using reversed-phase HPLC with ultraviolet and electrochemical detection

A sensitive and specific HPLC assay for the measurement of the antipsychotic compound quetiapine in human plasma has been developed and validated. The assay employs a three-step liquid liquid extraction of quetiapine and its 7-hydroxylated and 7-hydroxylated, N-dealkylated metabolites from human plasma, and utilizes ultraviolet (UV) detection of quetiapine and electrochemical detection of the metabolites. The method provides a linear response from a quantitation limit of 2.50 to 500 ng ml(-1) for each analyte using 0.4 ml plasma. The assay is applicable from 500 to 5000 ng ml(-1) by sample dilution with de-ionized water. The inter-assay precision of quetiapine in plasma calibration standards across 4 validation days averaged 11.9% relative standard deviation (RSD) over the range 2.50 to 500 ng ml(-1), with intra-assay precision averaging 16.0% RSD and mean accuracy of 98.6% of theory. Similarly, the inter-assay precision of the 7-hydroxylated metabolite in plasma calibration standards across 4 validation days averaged 13.7% RSD over the range 2.50 to 500 ng ml(-1), with intra-assay precision averaging 17.6% RSD and mean accuracy of 109% of theory. The 7-hydroxylated, N-dealkylated metabolite demonstrated inter-assay precision of 16.2% RSD, intra-assay precision of 19.9% RSD, and mean accuracy of 104% of theory over the range 2.50 to 500 ng ml(-1). The present assay method was used to support a study comparing the pharmacokinetic profile of quetiapine with the time course of dopamine D2 and serotonin 5-HT2 receptor occupancy in the brain using positron emission tomography (PET). We describe in this paper the bioanalytical method and the plasma concentrations of quetiapine and its metabolites resulting from this study.

Imaging of the pediatric orbit and visual pathways: computed tomography and magnetic resonance imaging

Techniques for pediatric MR imaging and computed tomography and anatomy of the orbit and intracranial visual pathways are presented and reviewed in this article. Imaging findings are presented for the following categories of abnormality: a) orbital anomalies related to congenital disorders of the brain, b) disorders of the orbit (ocular, nonocular, or multicompartmental), c) disorders of the intracranial visual pathways (suprasellar cistern, optic radiations, or occipital cortex), and d) disorders of gaze (extraocular muscles, cranial nerves, and brainstem). Careful assessment of the clinical findings, anatomic location of the visual impairment, and familiarity with disorders that often affect pediatric patients are helpful in guiding neuroimaging evaluation of the child with ocular, orbital, or central patterns of visual disturbance.

Sedation for pediatric imaging studies

This article discusses safe sedation for pediatric imaging. Emphasis is placed upon implementation of an institutional sedation program according to guidelines of the American Academy of Pediatrics. Standards for patient assessment and preparation, sedative administration, monitoring, and discharge are reviewed. A comparison of available sedative agents is also provided.

Treatment of brain tumors in children is associated with abnormal MR spectroscopic ratios in brain tissue remote from the tumor site

PURPOSE

Children who have brain tumors are at risk for a variety of treatment-related sequelae, including neuropsychological and cognitive impairment, neurologic deficits, and neuroendocrinologic disturbances. We sought to determine the value of proton MR spectroscopy in assessing brain tissue remote from the tumor site to ascertain the effects of chemotherapy and radiation treatment in these patients.

METHODS

Single-voxel proton MR spectra from 70 patients (111 spectra) and 11 healthy volunteers (11 spectra) were analyzed. NAA/Cr, NAA/Cho, and Cho/Cr ratios based on peak areas were obtained from nonneoplastic regions of the frontal lobe. The relationship between MR spectroscopic ratios and treatment was determined.

RESULTS

NAA-containing ratios were decreased in patients as compared with control subjects. The presence of gadolinium-based contrast material did not cause significant changes in the ratios as compared with precontrast data. When chemotherapy was a component of a child's treatment protocol, we found a significant decline in NAA/Cr ratios. Patients who underwent both chemotherapy and radiation therapy showed a trend toward lower NAA-containing ratios if the chemotherapy was administered before the radiation therapy. Patients receiving whole-brain radiation had a trend toward lower NAA-containing ratios than did those who had only focal tumor treatment.

CONCLUSION

In children with brain tumors, MR spectroscopy of brain tissue remote from the tumor reveals treatment-related biochemical changes.

Intracranial aneurysms in infants and children

BACKGROUND

The diagnosis and imaging of pediatric aneurysms has changed since the advent of MR and MRA.

OBJECTIVE

To update the literature on pediatric aneurysms and better define the appropriate work-up of childhood aneurysms in 1997.

MATERIALS AND METHODS

Retrospective review of 21 children (12 boys, 9 girls) with 25 aneurysms from three institutions over a 20-year period was performed. Imaging studies were mixed and included CT (19 patients), MR (11 patients), MRA (6 patients) and angiography (18 patients).

RESULTS

Eighteen of 25 aneurysms were congenital saccular, 6 were mycotic, and 1 was post-traumatic. Of these, 44 % were in the posterior circulation. Nine aneurysms arose from distal arterial branches. Forty percent were large (between 1-2.5 cm) and 16 % were giant (> 2.5 cm). CT and MR showed hemorrhage, and frequently revealed the aneurysms as a focal mass with or without enhancement and flow void. Six children had MRA which revealed aneurysms in four patients. All patients with MRA had corresponding conventional angiography.

CONCLUSION

Characteristics of pediatric aneurysms include diversity of type, increased incidence in the posterior fossa, peripheral location, and large size. CT, MR and MRA are useful in the diagnosis with conventional angiography essential for preoperative planning.

MOPP or radiation in addition to ABVD in the treatment of pathologically staged advanced Hodgkin's disease in children: results of the Children's Cancer Group Phase III Trial

PURPOSE

A randomized trial designed to compare mechlorethamine, vincristine, procarbazine, and prednisone (MOPP)/doxorubicin, bleomycin, vinblastine, and daccarbazine (ABVD) (regimen A) with ABVD plus low-dose regional (extended-field) radiation therapy (EF RT) (regimen B) for the treatment of children and adolescents with stages III and IV Hodgkin's disease was conducted by the Children's Cancer Group (CCG-521) from 1986 until 1990.

PATIENTS AND METHODS

One hundred eleven eligible patients were randomized, 57 to regimen A and 54 to regimen B. All patients had pathologically verified stage III or stage IV Hodgkin's disease.

RESULTS

Overall survival (S) is 87% at 4 years and event-free survival (EFS) is 82%. Patients randomized to ABVD plus EF RT have a 4-year EFS of 87% compared with 77% for patients randomized to MOPP/ABVD (P = .09, two-sided). Patients randomized to ABVD plus EF RT have a 4-year S of 90% compared with 84% for patients randomized to MOPP/ABVD (P = .45, two-sided). Significant prognostic factors in multivariate analysis for EFS are stage of disease, erythrocyte sedimentation rate (ESR) at diagnosis, liver size at diagnosis, and, among stage III patients, the size of the mediastinal mass at diagnosis. The acute toxicities of treatment are largely hematopoietic in nature, whereas acute pulmonary and cardiac toxicities are modest and not limiting.

CONCLUSION

The results of this study show that, in advanced-stage Hodgkin's disease in children, equivalent results can be obtained by the addition of either MOPP or low-dose EF RT to the ABVD regimen; whether the addition of either contributes to outcome was not addressed in this study and will require additional testing. It is clear, however, that MOPP chemotherapy can safely be eliminated from front-line combination chemotherapy regimens for advanced Hodgkin's disease in pediatric patients.

Inversion-recovery echo-planar MR in adult brain neoplasia

PURPOSE

A T1-weighted multishot inversion-recovery (IR) echo-planar MR imaging (EPI) sequence was developed to improve intracranial tissue differentiation; its diagnostic utility was compared with that of conventional axial T1-weighted spin-echo and axial T2-weighted turbo spin-echo sequences.

METHODS

Eighteen patients with known or suspected primary or metastatic brain neoplasia were imaged in a 1.5-T unit with IR-EPI sequences. Three observers measured gray/white matter contrast-to-noise ratios and subjectively compared IR-EPI sequences with T1-weighted spin-echo and T2-weighted turbo spin-echo sequences for gray/white matter discrimination, visibility of intracranial and vascular structures, overall lesion conspicuity, size of lesion(s), and presence and severity of artifacts.

RESULTS

Twenty-four lesions (including neoplasia, infarction, treatment-associated encephalomalacia, nonneoplastic white matter signal abnormalities, and basilar artery dolichoectasia) were detected in 12 patients. Basilar artery dolichoectasia was not included in subsequent statistical analysis. Pulsatile flow artifacts were markedly reduced on IR-EPI sequences relative to those on T1-weighted spin-echo sequences. Gray/white matter contrast was greater on IR-EPI images than on T1-weighted spin-echo images. Periaqueductal gray matter, basal ganglia, optic tracts, cranial nerve V, and claustrum were seen better or as well on IR-EPI images as compared with T1-weighted spin-echo images. IR-EPI was more sensitive to magnetic sensitivity effects, with resultant decreased visibility of cranial nerves VII and VIII and the orbital portion of the optic nerves. For noncontrast sequences, lesion conspicuity was better on IR-EPI images than on T1-weighted spin-echo images in 16 (70%) of 23 lesions and was equal on the two sequences in seven (30%) of 23 lesions. Lesion size, including surrounding edema, was greater on IR-EPI images than on T2-weighted turbo spin-echo images in two (9%) of 23 cases and equal in 21 (91%) of 23 cases. Hyperintense foci of methemoglobin were more conspicuous on T1-weighted spin-echo images.

CONCLUSION

Multishot IR-EPI is superior to conventional T1-weighted spin-echo imaging for parenchymal tissue contrast and lesion conspicuity, and is equal to T2-weighted turbo spin-echo imaging in sensitivity to pathologic entities.

Moyamoya disease in the United States

The epidemiology and radiological features of Moyamoya disease (MMD) in the US were investigated. This study encompassed 98 cases; 26 were newly collected from eight US institutions and 72 were previously reported in the US literature. The patients ranged in age from 6 months to 67 years with age peaks in the first, third and fourth decades. MMD was seen in various ethnic groups and females were more commonly involved (71%) than males. A specific etiology could not be determined in most cases but arteriosclerosis and use of oral contraceptives were occasional associations. On angiography and/or magnetic resonance angiography (MRA), carotid arterial stenosis or occlusion was seen bilaterally in 95 cases (97%) and unilaterally in three. On MR or MRA, internal carotid steno-occlusive lesions were well demonstrated in all cases but Moyamoya collateral vessels (MMVs) were visualized in only 65% of the patients. MMVs in the basal ganglia and thalami were best demonstrated on T1 weighted images. Parenchymal lesions were seen in all patients and were often bilateral. With advances in MR techniques and increasing awareness of diagnostic guidelines, MMD will be diagnosed more frequently than before in the US.

Optic nerve hypoplasia: absence of posterior pituitary bright signal on magnetic resonance imaging correlates with diabetes insipidus

PURPOSE

Magnetic resonance imaging has been used to examine children with optic nerve hypoplasia for pituitary abnormalities who may be at risk for anterior pituitary hormonal deficiencies. We correlated the sellar and optic pathway anatomic findings on magnetic resonance imaging in children with optic nerve hypoplasia with findings from their endocrinologic and ophthalmologic examinations to determine whether magnetic resonance imaging findings predict anterior and posterior pituitary dysfunction.

METHODS

A retrospective review identified five children with optic nerve hypoplasia and endocrinopathy who also underwent high resolution volumetric magnetic resonance imaging.

RESULTS

All children had severe bilateral optic nerve hypoplasia and anterior pituitary hormone deficiencies. Three children had no recognizable intrasellar or ectopic posterior pituitary bright spot on magnetic resonance imaging; all had clinical evidence of diabetes insipidus. Two patients with a recognizable but ectopic posterior pituitary did not have diabetes insipidus.

CONCLUSION

Children with optic nerve hypoplasia and no recognizable posterior lobe of the pituitary gland on magnetic resonance imaging are at risk for both anterior and posterior pituitary dysfunction, whereas those with a posterior lobe on magnetic resonance imaging appear to have intact posterior pituitary function.

Adult cerebrovascular disease: role of modified rapid fluid-attenuated inversion-recovery sequences

PURPOSE

To compare a rapid fluid-attenuated inversion-recovery (FLAIR) sequence with T1-weighted, fast spin-echo proton density-weighted, and T2-weighted images in the evaluation of cerebrovascular disease.

METHODS

All patients underwent standard T1-, proton density-, and T2-weighted fast spin-echo and fast FLAIR MR imaging at 1.5 T. Images were compared for lesion size, location, and conspicuity.

RESULTS

Forty-five infarctions were identified on T2-weighted and fast FLAIR sequences. Lesion size was comparable on the proton density-weighted, fast T2-weighted, and fast FLAIR sequences, although lesion conspicuity was superior on the fast FLAIR images in 43 (96%) of the lesions. Associated periventricular and pontine hyperintensities were more extensive on the fast FLAIR images.

CONCLUSION

Our modified fast FLAIR technique provided improved conspicuity of infarctions and white matter disease as compared with T1-, proton density-, and T2-weighted spin-echo images, and a reduced scan time compared with conventional FLAIR sequences in patients with cerebrovascular disease.

MR of the brain in children

MR imaging has firmly established its place as the cornerstone of pediatric neuroimaging. Recent advances in MR imaging have led to decreased imaging time, high resolution studies, and new methods for obtaining tissue contrast. Magnetic resonance angiography (MRA) now obviates the need for angiography in some children, although its extended role is still to be defined. Normal and abnormal development and myelination patterns have been further defined with MR imaging. The patterns of brain injury resulting from hypoxia and ischemia vary with the degree of the insult as well as the gestational age of the child. These patterns of hypoxic-ischemic encephalopathy can be analyzed to determine when the insult occurred. Neuronal migration disorders and phakomatoses can be diagnosed with confidence at an early age, thus facilitating genetic counseling. MR imaging can detect the most common lesions associated with childhood epilepsy, such as hippocampal sclerosis, focal cortical dysplasias, and low-grade tumors. Other areas, including pediatric AIDS, toxicity-related injury, metabolic/mitochondrial conditions, and disorders associated with iatrogenic injury, can be diagnosed with MR. Spectroscopy provides information that should prove useful in evaluating and monitoring neuronal and other brain tissue disorders in children.

Advances in neuroimaging of the visual pathways

PURPOSE

To provide a practical review for the ophthalmologist of advances in neuroimaging of the visual pathways.

METHODS

We reviewed recent advances in computed tomography, magnetic resonance imaging, and angiography that are applicable to visual pathways imaging.

RESULTS

For detailed ocular imaging, computed tomography complements ocular sonography for imaging of calcification, trauma, and masses. Magnetic resonance imaging may be helpful for localization and characterization of ocular masses in the setting of hemorrhage. For orbital imaging, computed tomography is most appropriate in the evaluation of suspected thyroid ophthalmopathy, infection, and trauma; otherwise, either computed tomography or magnetic resonance imaging is useful for detection and characterization of abnormality. For disorders affecting the sellar, retrochiasmal, and brainstem pathways, magnetic resonance imaging is the study of choice, except for acute hemorrhage, for which noncontrast computed tomography is preferable. Although magnetic resonance angiography has a role in the elective evaluation of cerebrovascular disease, conventional angiography is the definitive study for suspected aneurysm and for surgical planning.

CONCLUSIONS

A practical approach for selection of the most appropriate imaging modalities by the ophthalmologist is suggested on the basis of the anatomic location and type of disease suspected.

Tntraoperative vesical pressure measurements as a guide in the closure of abdominal wall defects

Increased intra-abdominal pressure represents a difficult problem when closing abdominal wall defects (AWD) and can cause renal insufficiency and vascular injury to the intestine with the development of necrotizing enterocolitis. Urinary bladder pressure measurements have been shown to accurately reflect intra-abdominal pressure in animal models. This study compares outcomes with and without vesical pressure measurements in AWD. Since its description in 1987, these vesical pressure measurements have guided the closure of AWDs. A pressure of <20 cm H2O allows closure by primary fascial, skin, or staged prosthetic closure. All charts of patients who underwent AWD closure from 1981 to 1993 were reviewed and data collected including type of defect and closure, gestational age, weight, age at operation, fluid requirements and urinary outputs, ventilator requirements, days to first and total feeding, total parenteral nutrition (TPN) days, hospital days, hospital charges, morbidity, and mortality. Results were analyzed by paired or unpaired Student's t test or Fisher's exact test. Twenty-seven infants did not receive vesical pressure measurements, whereas 13 did. No significant differences occurred in the parameters recorded in these two diverse groups. When gastroschisis patients only were compared, a significant decrease in intravenous fluid requirements in the vesical measurement group occurred on postoperative Day 2 (155.3+/- 37.5 versus 109.6 +/- 34.3; P = 0.016), and a significant decrease in urinary output occurred on postoperative Day 3 (4.2 +/- 112 versus 3.1+/- 1.1; P=0.044). Ventilator support, TPN days, and oral feeding data were all lower in the vesical measurement group but did not reach statistical significance. Hospital days and hospital changes showed a trend to lower values in the measured group (P values 0.052 and 0.095, respectively). Intraoperative vesical pressure measurements represent a simple, safe, effective method to guide the closing of AWD and result in less capillary leak and more prompt diuresis, and may result in significantly less morbidity, mortality, and cost.

Clinical, neurodiagnostic, and MR findings in children with spinal and brain stem multiple sclerosis

PURPOSE

To describe the clinical, neurodiagnostic, and MR findings in seven children with brain stem and spinal multiple sclerosis.

METHODS

Spinal or brain stem multiple sclerosis was diagnosed in seven children between 1986 and 1992. All patients had neurologic and MR examinations as well as neurodiagnostic testing, including spinal fluid analysis and brain stem and auditory evoked potentials.

RESULTS

Three children had clinical findings and masslike lesions in the brain stem (two) or spinal cord (one) suggestive of neoplasm, which prompted biopsy (two) or radiation therapy (one). Five of six patients with spinal involvement had cord swelling with increased signal on T2-weighted images over at least three cord segments, and two children had essentially holocord involvement. Three children had normal cranial MR at presentation.

CONCLUSIONS

Multiple sclerosis involvement of the brain stem and spinal cord may be associated with extensive swelling and MR signal changes suggestive of neoplasm without typical cerebral white matter abnormalities. Serial clinical and neuroimaging examinations may be necessary to make a definitive diagnosis of multiple sclerosis in children.

The CERAD experience, Part VIII: Neuroimaging-neuropathology correlates of temporal lobe changes in Alzheimer's disease

We compared premortem neuroimaging findings with neuropathologic evidence of temporal lobe atrophy in 20 patients with Alzheimer's disease (AD) confirmed by autopsy. There were significant correlations between temporal horn enlargement observed by neuroimaging and hippocampal atrophy at autopsy, and between the overall cerebral atrophy severity on neuroimaging and scores on the Mini-Mental State Examination. This report confirms previous studies correlating temporal lobe atrophy on neuroimaging with a clinical diagnosis of AD, although more precise neuroimaging techniques are needed for use in multicenter studies of AD.

High frequency of telomeric association in a family with multiple congenital neoplasia

Chromosomal analysis of the peripheral blood cultures of a married couple whose second pregnancy gave birth to twin daughters with multiple congenital malignancies revealed normal karyotypes of 46,XX and 46,XY, respectively. However, in the father's blood, 23.3% of metaphases showed telomere-telomere associations involving single-single and double-double chromatids. Such associations were not observed in the metaphases of the mother. We speculate from these observations that the father's genotype may somehow be responsible for the congenital malignancies in their twin daughters.

Delayed intracranial hemorrhage in children after suboccipital craniectomy

OBJECTIVE

The purpose of this study was to report the clinical and imaging findings of seven children who developed extraaxial, intracranial hemorrhage 3-12 years after suboccipital craniectomy for neoplasia. We attempt to explain the hemorrhages based on a previously reported hypothesis of neomembrane formation associated with dural substitutes used to repair large dural defects.

MATERIALS AND METHODS

Clinical charts (seven patients), surgical and pathologic findings (four patients), and imaging studies (CT scans and MR images in four; CT scans, MR images, and angiograms in one; and CT scans only in two patients) were reviewed retrospectively. Hemorrhage occurred 3-12 years after suboccipital craniectomy for tumor (ependymoma in two, medulloblastoma in three, astrocytoma in one, and ganglioglioma in one). Silastic dural substitute was used to repair the surgical wound in six cases and human dural graft in one case. Hematomas were spontaneous in four and occurred after minor head trauma in three. Four patients had multiple hemorrhagic episodes.

RESULTS

CT scans and MR images showed acute extraaxial hemorrhages at the craniectomy site without contiguous residual or recurrent neoplasia in all patients. No intraaxial or intratumoral hemorrhage was detected. Findings on cerebral angiograms in one patient were normal. Four patients underwent surgical exploration of the hematoma and craniectomy site; no macroscopic source of bleeding was detected. The hematomas were not associated with recurrent tumor pathologically.

CONCLUSION

Delayed, benign extraaxial hematomas may occur in children who have undergone craniectomy for tumors of the posterior fossa and have had dural substitute used to repair large defects. Fragile vessels associated with nonmembranes have been proposed as the source of hemorrhage.

The brain in older persons with and without dementia: findings on MR, PET, and SPECT images

Neuroimaging plays an increasingly important role in the evaluation of dementias of older adults. Although no unequivocal diagnostic test other than biopsy is currently available for Alzheimer's disease and some other dementias during life, neuroimaging techniques are an integral part of the examination and follow-up of patients with dementia. This review describes findings in the brains of patients with normal aging and in elderly patients with dementia, as shown by MR imaging and MR spectroscopy, positron emission tomography (PET), and single-photon emission computed tomography (SPECT) and correlated with clinical and pathologic features.

Anatomic and physiologic imaging of Alzheimer's disease

At present, no imaging modality is considered the standard diagnostic test for AD. On anatomic studies, severity of temporal lobe and hippocampal atrophy are the most reliable findings in AD, although overlap of these findings among AD, aging, and other dementias mitigate the value of these measures for application to the individual case. Although somewhat cumbersome for routine use, quantitative MR measurements offer more precise comparison of degrees of atrophy. Functional imaging may demonstrate abnormalities of perfusion or metabolism that precede anatomic changes (PET, SPECT, or MRS), yet these techniques generally require additional anatomic information from MR for interpretation. Newer investigational MR techniques such as MRS and functional MR in combination with conventional MR imaging have the potential to combine metabolic with anatomic imaging in one examination. A combination of both metabolic and anatomic imaging studies may ultimately offer better sensitivity and specificity for diagnosis, monitoring, and follow-up of AD.