Diagnosing aneurysmal and unicameral bone cysts with magnetic resonance imaging

The differential between aneurysmal bone cysts and unicameral bone cysts usually is clear clinically and radiographically. Occasionally there are cases in which the diagnosis is not clear. Because natural history and treatment are different, the ability to distinguish between these two entities before surgery is important. The authors reviewed, in a blinded fashion, the preoperative magnetic resonance images to investigate criteria that could be used to differentiate between the two lesions. All patients had operative or pathologic confirmation of an aneurysmal bone cyst or unicameral bone cyst. The authors analyzed the preoperative magnetic resonance images of 14 patients with diagnostically difficult bone cysts (eight children with unicameral bone cysts and six children with aneurysmal bone cysts) and correlated these findings with diagnosis after biopsy or cyst aspiration and contrast injection. The presence of a double density fluid level within the lesion strongly indicated that the lesion was an aneurysmal bone cyst, rather than a unicameral bone cyst. Other criteria that suggested the lesion was an aneurysmal bone cyst were the presence of septations within the lesion and signal characteristics of low intensity on T1 images and high intensity on T2 images. The authors identified a way of helping to differentiate between aneurysmal bone cysts and unicameral bone cysts on magnetic resonance images. Double density fluid level, septation, and low signal on T1 images and high signal on T2 images strongly suggest the bone cyst in question is an aneurysmal bone cyst, rather than a unicameral bone cyst. This may be helpful before surgery for the child who has a cystic lesion for which radiographic features do not allow a clear differentiation of unicameral bone cyst from aneurysmal bone cyst.

Pathology and behavior of small breast carcinomas

Mammographic screening and increased public awareness have changed the clinical spectrum of breast carcinoma with important implications for therapy. Small invasive breast carcinomas T1a,b, defined as 1.0 cm or less in maximum diameter, now comprise 22% of invasive carcinomas in our institution, enabling comparison of 273 T1a,b with 563 T1c (1.1 to 2.0 cm), 447 T2 (2.1 to 5.0 cm), and 40 T3 (>5 cm) carcinomas. Nuclear measurements were made with calibrated ocular grids. Hormone receptors were measured in cytosol or immunohistochemically. S-phase fraction (SPF) was measured prospectively on all carcinomas by counting cells in histologic preparations after vitro labeling with tritiated thymidine or 5-bromo-2'deoxyuridine. T1a (0.2 to 0.5 cm) carcinomas were similar to T1b (0.6 to 1.0 cm) in histologic and biologic features, but T1b carcinomas had higher detection rates of axillary metastasis (0% v 10%). The latter may reflect longer duration of metastases, permitting growth to detectable size. Low-grade carcinoma types (mucinous, tubular, cribriform) became less frequent as T stage increased, with the major decrease occurring at T1b (0.6 to 1.0 cm)/T1c (1.1 to 2.0 cm) boundary. T1a,b carcinomas preponderantly had low-grade histologic and biochemical characteristics and low SPF. SPF increased significantly with increasing tumor size from T1b through T2 but not beyond T2. Increases in proportion of patients with axillary metastases occurred over each T transition. Estrogen and progesterone receptor (ER, PgR) positivity decreased with increasing stage. Larger tumors were significantly associated with younger patient age. While this may reflect ease of diagnosing small carcinomas after the menopause, young age was also associated with predictors of aggressive tumor behavior (high SPF, negative assays for ER, PgR). T1a,b patients with mid or high SPF or axillary metastases were more likely than others to have received cytotoxic adjuvant therapy. Conclusions are: (1) Development of cell lines that have metastatic capability appears to occur near the T1b/T1c interface, but they exist very early in some carcinomas. (2) T1a carcinomas may be managed without axillary dissection. When T1b patients are candidates for adjuvant therapy, we advocate sentinel node biopsy with intensive study for micrometastases. (3) Accurate determination of size is very important in prognosis of small breast carcinomas. (4) Prognostic efficacy of proliferation and other prognostic markers in retrospective studies, but not in our patients who often received adjuvant therapy, suggest that micrometastases from small breast carcinomas are highly responsive to adjuvant chemo/hormonal therapy.

Behavioral responses to a D1 dopamine agonist in weanling rats treated neonatally with cocaine and delta9-tetrahydrocannabinol

We determined whether neonatal exposure to cocaine with or without delta9-tetrahydrocannabinol (THC) altered the behavioral responses of weanling rats to the full D1 dopamine (DA) agonist SKF 81297. Rats were injected SC once daily from postnatal day (PD) 1 through 5 with cocaine (20 mg/kg), the same dose of cocaine plus THC (10 mg/kg), or drug vehicle. On PDs 24, 25, or 26, male and female littermates were administered 3 or 10 mg/kg of SKF 81297 or saline vehicle, and then tested 15 min later in an open-field apparatus. Neither neonatal drug treatment nor gender influenced the behavioral responses to SKF 81297. The drug challenge did, however, produce several dose-dependent behavioral effects, including increases in locomotor activity, line crossing, sniffing, and headshakes, and a decreased incidence of rearing, grooming, and stationary behavior. Furthermore, even though earlier administration of cocaine and THC failed to alter D1 receptor sensitivity, animals in both neonatal treatment groups exhibited an overall increase in grooming behavior and a decrease in sniffing compared to controls when the results were combined across doses of SKF 81297. These findings indicate that early postnatal exposure to cocaine can alter certain behaviors independently of functional changes in the D1 receptor system.

Biological considerations with pelvic neoplasms

The strategy of therapy for any neoplasm is determined to a significant degree by the biological characteristics of the neoplasm. The ones benefited most by surgical ablation are the cancers that grow locally but never metastasize. The second group is composed of neoplasms with exceedingly slow growth rates permitting long periods of symptom-free survival before recidivation. Many such cancers occur in pelvic structures requiring understanding of the nature of the cancers and then techniques necessary for their resection. The review provides an introduction to some of the relevant biological considerations.

Assessment of increase in renal pelvic size on post-void sonography as a predictor of vesicoureteral reflux

BACKGROUND

During the course of our routine renal ultrasound examinations, we noticed that some children who developed dilatation of a renal pelvis following voiding had reflux found on voiding cystourethrography (VCUG).

PURPOSE

To determine if increase in renal pelvic size on post-void ultrasound is an accurate predictor of vesicoureteral reflux.

MATERIALS AND METHODS

Fifty-seven children (113 kidneys) underwent renal ultrasound and VCUG on the same day. Anteroposterior dimensions of the renal pelves were prospectively measured on ultrasound prior to and following patient voiding and correlated with the results of the VCUG.

RESULTS

The diameter of the renal pelvis increased in 12 and decreased in 38 kidneys on post-void ultrasound. Vesicoureteral reflux occurred in 19 kidneys and among these kidneys, renal pelvic diameter increased in 2, decreased in 7, and was unchanged in 10 following voiding. There was no significant correlation between post-void change in renal pelvic diameter and the presence of vesicoureteral reflux.

CONCLUSION

Increase in renal pelvic size on post-void ultrasound is not a reliable indicator of vesicoureteral reflux.

Pyomyositis in children and adolescents: report of 12 cases and review of the literature

Pyomyositis initially was observed more commonly in the developing world but now is reported with increasing frequency in the United States. The presentation is nonspecific and the differential diagnoses are many. We found the clinical history, laboratory findings, and response to treatment similar to those observed in different areas of the world. Magnetic resonance imaging (MRI) with gadolinium injection, in addition to helping to make the diagnosis, may help differentiate between early and late stages that help guide treatment. Coexisting bone changes (58%) may represent either the sensitivity of MRI to reactive inflammatory changes or the presence of a coexisting osteomyelitis. All patients responded to antibiotics and drainage if abscesses were present. Although the optimal duration of antibiotic therapy remains unclear, a shorter course should be considered in patients with a good clinical response, even when MRI shows nonspecific bony abnormalities. Percutaneous drainage was successful in five cases and may represent an alternative to the traditional surgical approach.

Factors influencing survival among patients with vascular dementia and Alzheimer's disease

BACKGROUND AND PURPOSE

Vascular dementia (VAD) and dementia of the Alzheimer type (DAT) are malignant conditions of the elderly. More information is required to clarify expected lengths of survival, which condition is more lethal, and which risk factors may influence survival duration.

METHODS

Cross-sectional and longitudinal designs were used. Survival interval was the period after study admission to death. From a population of 392 patients (of the 150 patients with VAD, mean age at entry was 68.3 years, of the 242 patients with DAT, mean age at entry was 73.0 years), there were 52 deaths, 26 patients with VAD and 26 patients with DAT. Pre-entry dementia symptoms were present for a mean of 3.1 years, with median follow-up of 3.6 years. Among 236 control subjects, there were 19 deaths. Entry age was 69.5 years, with median follow-up of 8.8 years. Influences of risk factors for stroke and body mass index on symptom duration, survival intervals, and cause of death were evaluated.

RESULTS

Family history of neurodegenerative disorders, principally DAT, negatively influenced DAT survival. Body mass index declined with age and duration of pre-entry symptoms among men and women in all three groups. Before entry, for men, dementia symptoms were present for shorter periods compared with women. After entry, VAD and DAT patients had similar survival intervals. Causes of death were similarly distributed (78% of patients with VAD died from vascular causes, 56% of patients with DAT and 67% of the controls).

CONCLUSION

VAD and DAT are malignant conditions negatively influencing survival times. Being a woman seems to play a protective role in symptom duration before diagnosis, but after diagnosis survival times of men and women were similar. We attribute equivalence of survival intervals among dementia groups to control of risk factors for cerebrovascular disease.

Transformed Migraine Is a Cause of Chronic Daily Headaches

Chronic daily headaches (CDH) consist of episodes of head pain occurring daily; more than 15 days each month; often associated with a history of migraine, with or without aura; or with a history of tension-type headaches occurring alone or both occurring together. Chronic daily headaches are frequently associated with rebound headaches after ergotamine, barbiturate, caffeine, and analgesic abuse. We previously reported that migraineurs with typical intermittent headaches exhibited excessive cerebral cortical vasodilation after oral acetazolamide which usually precipitated and reproduced their typical headaches. In the present study, cerebral vasodilator responses were tested by measuring changes in local cerebral blood flow (Delta LCBF) utilizing xenon-contrasted CT scanning, before and after oral administration of 14.3 mg/kg of acetazolamide, in 11 patients with CDH. The results were compared with 12 age-matched typical migraineurs, with and without aura, who had a history of migraine attacks occurring at intervals of 1 month or longer. Global and subcortical gray and white matter Delta LCBFs were quantitated and compared between both groups. After acetazolamide, Delta LCBF increased in cortical gray matter by 11.8% among patients with CDH and by 16.7% among migraineurs, with no significant differences between groups. Typical migraine attacks were provoked by acetazolamide in 9 patients (82%) with CDH and in 11 (92%) migraineurs with intermittent headaches. These observations are taken as evidence that at least 82% of patients with CDH have transformed migraine as judged by the provocation by acetazolamide of typical migraine attacks associated with excessive Delta LCBF increases. Serotonin agonists should be considered in the treatment of CDH to avoid ergotamine, caffeine, barbiturate, and analgesic abuse.

Multiple vascular and bowel ruptures in an adolescent male with sporadic Ehlers-Danlos syndrome type IV

Ehlers-Danlos syndrome (EDS) type IV is a heritable disorder resulting from mutations in the COL3A1 gene that cause deficient production of type III collagen. Clinical manifestations of EDS type IV include hypermobility of small joints, excessive bruisability, thin translucent skin, poor wound healing, bowel rupture, and vascular rupture that is often fatal. A 14-year-old male without a family history of EDS died following multiple bowel and abdominal blood vessel ruptures. Even in areas apart from rupture sites, the bowel wall was thin because of diminished submucosa and muscularis propria. Similarly, the walls of blood vessels in bowel submucosa and elsewhere in the abdomen varied in thickness, and contained frayed and fragmented elastic tissue fibers. Fibroblasts cultured from the patient's skin secreted reduced quantities of type III collagen that was explained by a point mutation in one copy of the COL3A1 gene. EDS type IV should be strongly suspected in any patient with otherwise unexplainable bowel and/or vessel rupture.

Sentinel lymph node biopsy: strategies for pathologic examination of the specimen

BACKGROUND AND OBJECTIVES

Sentinel lymph node biopsy is a practical surgical procedure with high sensitivity for detection of metastases from breast carcinoma in the axilla. It offers economy by avoidance of axillary dissection in the majority of breast carcinoma patients who have negative sentinel node biopsies, and provides an opportunity to study axillary micrometastases with high efficiency in a small volume of tissue.

METHODS

Sentinel node tissue is sliced at 2-mm intervals for fixation and paraffin embedding. Probabilities of finding spherical micrometastases of specific sizes randomly distributed in lymph nodes were calculated geometrically for several microsectioning plans.

RESULTS AND CONCLUSIONS

Sentinel node tissue can studied by systematic serial sectioning technique designed to find metastases of given diameters with specific probabilities. A procedure whereby three microsections are prepared repeatedly at intervals of 250 microm appears to be practical. Two sections from each level can be examined by routine staining and the third by immunohistochemical stain; the latter is recommended particularly for infiltrating lobular carcinoma. This method will find metastases of 0.25-mm diameter with theoretical probability of 1, and metastases of 0.10-mm diameter with probability of 0.46, with reasonable costs. Metastases of these sizes are consequential and worth finding on biological and clinical grounds.

Relationship between [125I]RTI-55-labeled cocaine binding sites and the serotonin transporter in rat placenta

We investigated the characteristics of cocainelike binding sites in rat placenta using [125I]RTI-55. [3H]paroxetine binding and immunocytochemical staining for serotonin [5-hydroxytryptamine (5-HT)] and for the 5-HT transporter were also used to obtain evidence for rat placental 5-HT uptake. [125I]RTI-55 saturation analyses with membranes from normal gestational day 20 placentas yielded curvilinear Scatchard plots that were resolved into high- and low-affinity components (mean dissociation constants of 0.29 and 7.9 nM, respectively). Drug competition studies with various monoamine uptake inhibitors gave rise to complex multiphasic displacement curves, although the results obtained with the selective 5-HT uptake inhibitor citalopram suggest that the 5-HT transporter is an important component of placental high-affinity [125I]RTI-55 binding. The presence of a rat placental 5-HT uptake system was additionally supported by the [3H]paroxetine binding experiments and by the presence throughout the placenta of immunoreactivity for 5-HT and the 5-HT transporter. Immunostaining with both antibodies was most intense in the junctional zone, whereas the density of [125I]RTI-55 binding sites was greater in the placental labyrinth. This discrepancy may be due to the fact that [125I]RTI-55 appears to be labeling additional cellular components besides the 5-HT transporter. The presence of cocaine- and antidepressant-sensitive 5-HT transporters in the placenta has important implications for the possible effects of these compounds on pregnancy and fetal development.

Vasodilator responses to acetazolamide tested in subtypes of vascular dementia

OBJECTIVES

Thirty seven vascular dementia (VAD) patients were categorized into eight subtypes based on clinical, radiological, and pathogenetic features. Cerebral vasodilator responses to acetazolamide were then compared with age-matched normal controls and stroke patients without dementia.

METHODS

VAD results were compared with 42 normals and 19 cognitively intact stroke patients. Regional cerebral vasodilator responses were quantitated utilizing xenon contrasted computed tomography measures of local cerebral blood flow (LCBF) before and after oral administration of acetazolamide. LCBF changes (DeltaLCBF) before and after acetazolamide were calculated within cortical and subcortical, gray and white matter. Clinical VAD subtypes were: type 1, multi-infarct dementia (MID); type 2, strategically placed infarcts; type 3, subcortical lacunar infarcts; type 4, Binswanger's subcortical arteriosclerotic leukoencephalopathy; type 5, subcortical infarctions due to cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), inflammatory angitis, or antiphospholipid antibodies; type 6, admixtures of above types; type 7, cerebral hemorrhagic lesions; and type 8, VAD combined with Alzheimer's disease (DAT). The group with subcortical VAD comprised types 3-5. The group with cortical VAD comprised the remainder (types 1, 2, and 6-8). Cerebral vasodilator responses were also compared between these two main groups.

RESULTS

Cerebral vasodilator responses identified differences between the two main groups of VAD patients, those with cortical and those with subcortical dementia. Leukoaraiosis was measurably greater in subcortical VAD compared with cortical VAD. Among subcortical VAD patients, cortical LCBF increases after administration of acetazolamide were greater compared with cortical VAD and with normal controls.

CONCLUSIONS

Cognitive impairments in subcortical VAD are attributable to cortical disconnection syndromes. This concept is supported by reduced perfusion in deactivated cortex. In patients with subcortical VAD, deactivated cortical LCBF becomes promptly activated by acetazolamide resulting in marked cortical LCBF increases. Leukoaraiosis is greater among VAD patients and leukoaraiosis contributes to cortical disconnections, confirmed by excessive cortical vasodilator responses to acetazolamide.

Differential diagnosis of pediatric musculoskeletal masses

MR imaging plays a major role in the evaluation of children with soft tissue and bone tumors. While the imaging characteristics of these lesions are often nonspecific, MR imaging provides valuable information on the extent of disease and relationship of tumors to the neurovascular bundle and other vital structures. This article reviews the radiographic and MR imaging appearances and clinical presentations of a wide range of musculoskeletal masses that occur in children.

Age-related cerebrovascular disease alters the symptomatic course of migraine

Migraine headaches usually decrease in frequency and severity and often cease during advancing age. Occasionally, migraineurs report late-life migrainous accompaniments, i.e., auras without headache, particularly when typical migraine attacks terminate or diminish following major or minor strokes, at which time the auras may become atypical. Clinical observations such as these suggest that degenerative cerebrovascular changes accompanying aging may modify the course of migraine headaches particularly those with aura. To test this hypothesis, we quantitated age-related changes in cerebral vasodilator capacitance by measuring local cerebral blood flow utilizing xenon contrast computed tomography (CT) scanning before and after oral administration of the pharmacological cerebral vasodilator, acetazolamide (Diamox). Measurements were compared among 27 normal volunteers without headache (aged 24-94 years; mean age 61.1 +/- 17.6) and 37 carefully categorized groups of migraine patients (aged 27-83 years; mean age 59.4 +/- 12.4). The normals comprised Group A. Migraineurs were divided into two subgroups: Group B consisted of 27 migraineurs with and without aura who continued to suffer from incapacitating and frequent headaches and Group C consisted of 10 migraineurs who no longer suffered from severe and frequent headaches, two of whom still complained of atypical auras of the "late-life migrainous accompaniments" type. Cerebral vasodilator capacitance significantly declined with advancing age among normals and the two groups of migraineurs, confirming the development of age-related cerebrovascular diseases. Global CBF increases after Diamox in Group B (with persistent and severe migraine), were significantly greater compared with normals without headache, and with Group C consisting of migraineurs whose headaches had decreased, subsided, or become replaced by late-life migrainous accompaniments (Group C). Results establish that cerebrovasodilator capacitance declines with advancing age, probably due to progressive cerebral atherosclerosis, since these declines were accentuated by risk factors for stroke, particularly TIAs or documented lacunar infarcts by CT. Progressive impairments of cerebral vasodilator capacitance among migraineurs were associated with: (i) reductions in frequency and severity of migrainous cephalalgia and (ii) appearance of late-life migrainous accompaniments.

The role of radiology in the diagnosis and follow-up of Langerhans cell histiocytosis

Diagnostic imaging plays a major role in the management of patients with Langerhans cell histiocytosis. Plain radiography depicts most lesions. Nuclear scintigraphy may detect additional areas of bone involvement, but its routine use is controversial. Ultrasonography may be used to evaluate the abdomen for evidence of solid organ involvement. CT and MR imaging are often of great value in clarifying and delineating findings seen on plain radiographs and other imaging modalities. Ultimately, the choice of imaging study depends on the patient's clinical presentation and the body part affected.

Tumors of the pediatric chest

A wide spectrum of malignant and benign diseases can present as tumors involving the chest in children. The imaging evaluation of these children is initially directed by clinical presentation and usually begins with a chest radiograph. Further imaging with CT, MRI, or rarely ultrasonography may be performed to better detect, localize, or characterize the lesion(s). The differential diagnosis of these tumors is guided not only by tumor location and characterization, but also by patient age and clinical presentation. Familiarity with the clinical and radiographic aspects of these diseases will help the radiologist to continue to play a crucial role in the diagnosis and management of these children.