Cervicofacial venous malformations. MRI features and interventional strategies

SUMMARY

We retrospectively evaluated 53 consecutive patients with cervicofacial venous malformation who had sclerotherapy. This review included a demographic analysis, MRI reexamination and tabulation of interventional therapeutic strategies. All patients whose MRI studies were included in this review demonstrated characteristic findings: space occupying lesion with hyperintense T2 signal abnormality, patchy contrast enhancement, and no flow signal on the gradient echo images.We concluded that a complete MRI work-up of these patients requires post-contrast scanning and gradient-echo imaging in addition to the standard T1 and T2 weighted spin echo imaging. The majority of patients had sporadic (non-familial) venous anomalies. Sinus pericranii (SP) was identified in six patients (11%) and blue rubber bleb nevus syndrome (BRBNS) was found in two patients (4%). MRI findings of sinus pericranii are discussed in detail. Although sodium tetradecyl and/or absolute ethanol are the most commonly used sclerosants, a wide variety of therapeutic strategies (depending on the nature of the abnormality) are also needed for these patients.

Pediatric varicocele embolization

Varicocele is a very common condition. Although some patients may have pain, it is usually asymptomatic. Treatment of adolescent and pediatric patients is based on the desire to prevent testicular dysfunction and infertility that may be irreversible in adulthood. Venous embolization of the spermatic vein is an effective and minimally invasive method to occlude the varicocele and is known to improve testicular size and function. Embolization can be optimized by use of sclerosant, such as sodium tetradecyl sulfate (STS) foam or ethanol to permanently occlude the internal spermatic vein. About 10 to 15% of patients have recurrent varicocele after embolization. This is usually due to collateral vessels, such as from the right spermatic vein or the splanchnic veins. Embolizing as low as possible, while preventing pampiniform phlebitis by externally compressing the external inguinal ring, and empiric bilateral embolization appear to have the best outcome for preventing recanalization. Complications of varicocele embolization are uncommon. They include pampiniform phlebitis and venous thromboembolism into the renal vein or pulmonary artery.

An appropriate diagnostic workup for suspected vascular birthmarks

Birthmarks are common and commonly ignored by patients and primary care doctors. Yet they sometimes represent significant vascular anomalies that require diagnosis and treatment. We summarize when and how to work up a variety of vascular anomalies.

Percutaneous Treatment of Low Flow Vascular Malformations

Low flow vascular malformations, especially venous and macrocystic lymphatic malformations, are effectively treated by percutaneous intralesional injection of sclerosant drugs, such as ethanol and detergent sclerosant drugs. Good to excellent results are possible in 75%-90% of patients who undergo serial sclerotherapy. Most adverse effects are manageable, but severe complications can result from the intravascular administration of ethanol. It is generally recommended that the treatment of vascular malformations be performed in a multidisciplinary setting by practitioners with appropriate training and support.

Infantile hepatic hemangiomas: clinical and imaging findings and their correlation with therapy

OBJECTIVE

This study was undertaken to determine different imaging patterns in infantile hepatic hemangiomas and to explore the relationship between clinical presentations, imaging findings, and response to therapy.

MATERIALS AND METHODS

The imaging studies and clinical records of all patients with infantile hepatic hemangiomas from two tertiary children's hospitals were reviewed. Univariate and multivariate stepwise logistic regression techniques were used to determine whether clinical presentation and imaging variables differentiated the type of treatment required.

RESULTS

Typical hemangiomas appeared as focal or multifocal T2-hyperintense spheres with centripetal contrast enhancement and dilated feeding and draining vessels. Three atypical patterns included focal mass lesions with central varix with or without direct shunts, focal mass with central necrosis or thrombosis, and massive hemangiomatous involvement of the liver with abdominal vascular compression. In general, patients with focal lesions without high flow needed no treatment, and those with central varix and direct shunts developed severe high-output cardiac failure that responded quickly to embolization. The pattern of massive replacement of liver was associated with hypothyroidism, abdominal compartment syndrome, and a high mortality rate. Multivariate analysis of 55 patients indicated that congestive heart failure was the only independent predictor of treatment (p = 0.005). The presence of a shunt was the only independent factor associated with embolization or surgery (p = 0.002).

CONCLUSION

Although the imaging features of infantile hepatic hemangiomas vary to some extent, MRI features are typical in most patients and certain imaging findings are predictive of the clinical course. MRI is the technique of choice in diagnosing infantile hepatic masses.

Wilms tumor screening is unnecessary in Klippel-Trenaunay syndrome

BACKGROUND

Children with hemihypertrophy are screened for Wilms tumor, because this condition is a risk factor for developing the neoplasm. Patients with Klippel-Trenaunay syndrome (KTS) are often considered potential candidates for Wilms tumor, because they have unilateral overgrowth of the lower limb. In our experience, however, an association between KTS and Wilms tumor has not been observed.

METHODS

To determine whether KTS and Wilms tumor are associated, we reviewed our institutional experience for patients with both diagnoses and searched the Klippel-Trenaunay literature for patients with Wilms tumor. The National Wilms Tumor Study Group database also was studied to identify patients with KTS. Two-sided exact binomial tests were used to evaluate whether patients with 1 condition had an increased risk for the other. Ninety-five percent confidence intervals for these 2 risks were compared with the general population risks of Wilms tumor (1 in 10 000) and KTS (1 in 47 313).

RESULTS

None of the 115 patients with KTS followed at our institution developed Wilms tumor. One case of Wilms tumor has been reported in 1363 patients with KTS in the literature, giving a confidence interval of (1/57 377) and (1/267). None of the 8614 patients in the National Wilms Tumor Study Group database had KTS, giving a confidence interval of (0, 1/2336). Because the risks of KTS and Wilms tumor in the population fall within these confidence intervals, one cannot conclude that the risks of KTS among Wilms tumor patients or Wilms tumor among KTS patients are any different from the corresponding risks in the general population.

CONCLUSIONS

Patients with KTS are not at increased risk for developing Wilms tumor and thus should not undergo routine ultrasonographic screening.

Superiority of Pentobarbital versus Chloral Hydrate for Sedation in Infants during Imaging

PURPOSE

To compare the effectiveness and safety of oral pentobarbital and oral chloral hydrate for sedation in infants younger than 1 year during magnetic resonance (MR) imaging and computed tomography (CT).

MATERIALS AND METHODS

A computerized database was used to collect information about all cases in which sedation was used. Outcomes of all infants who received oral pentobarbital or oral chloral hydrate for sedation between 1997 and 2002 were reviewed. Two study groups were compared for sedation and discharge times by using Student t test and for adverse events by using Fisher exact test and multiple logistic regression analysis.

RESULTS

Infants (n = 1,316) received an oral medication for sedation. Mean doses were 50 mg/kg chloral hydrate and 4 mg/kg pentobarbital. Student t test demonstrated no difference in mean time to sedation and in time to discharge between groups. Overall adverse event rate during sedation was lower with pentobarbital (0.5%) than with chloral hydrate (2.7%) (P <.001). There were fewer episodes of oxygen desaturation with pentobarbital (0.2%) than with chloral hydrate (1.6%) (P <.01). Both medications were equally effective in providing successful sedation.

CONCLUSION

Although oral pentobarbital and oral chloral hydrate are equally effective, the incidence of adverse events with pentobarbital was significantly reduced.

Effects of IV Pentobarbital With and Without Fentanyl on End-Tidal Carbon Dioxide Levels During Deep Sedation of Pediatric Patients Undergoing MRI

OBJECTIVE

IV pentobarbital is used in radiology departments for sedating pediatric patients undergoing diagnostic imaging. To our knowledge, no published studies have documented end-tidal carbon dioxide levels during sedation with IV pentobarbital. The purpose of this prospective study was to determine the effects of different doses of IV pentobarbital with or without fentanyl on end-tidal carbon dioxide levels during deep sedation of pediatric patients undergoing MRI.

SUBJECTS AND METHODS

One hundred sixty-five patients (70 girls, 95 boys) having a mean age of 3.4 years received IV pentobarbital sedation with or without fentanyl for undergoing MRI from January through March 2002. Each child was sedated with 2-6 mg/kg of body weight of IV pentobarbital and an additional 1-3 micro g/kg of fentanyl if needed. After the administration of sedation, a 28-ft (8.5 m) nasal cannula with capnography capability was applied to each patient, and capnogram tracings and values were recorded every 5 min.

RESULTS

Mean values of end-tidal carbon dioxide were between 37 and 42 mm Hg during 60 min of sedation for both groups. When IV pentobarbital was used alone, no significant difference was seen between patients who received 3-5 mg of pentobarbital and those who received more than 5 mg (p = 0.97, F test).

CONCLUSION

End-tidal carbon dioxide levels remain within normal clinical range during sedation with IV pentobarbital with or without fentanyl. Our sedation protocol produced no significant deviations from normal respiratory parameters.

Capillary malformation-arteriovenous malformation, a new clinical and genetic disorder caused by RASA1 mutations

Capillary malformation (CM), or "port-wine stain," is a common cutaneous vascular anomaly that initially appears as a red macular stain that darkens over years. CM also occurs in several combined vascular anomalies that exhibit hypertrophy, such as Sturge-Weber syndrome, Klippel-Trenaunay syndrome, and Parkes Weber syndrome. Occasional familial segregation of CM suggests that there is genetic susceptibility, underscored by the identification of a large locus, CMC1, on chromosome 5q. We used genetic fine mapping with polymorphic markers to reduce the size of the CMC1 locus. A positional candidate gene, RASA1, encoding p120-RasGAP, was screened for mutations in 17 families. Heterozygous inactivating RASA1 mutations were detected in six families manifesting atypical CMs that were multiple, small, round to oval in shape, and pinkish red in color. In addition to CM, either arteriovenous malformation, arteriovenous fistula, or Parkes Weber syndrome was documented in all the families with a mutation. We named this newly identified association caused by RASA1 mutations "CM-AVM," for capillary malformation-arteriovenous malformation. The phenotypic variability can be explained by the involvement of p120-RasGAP in signaling for various growth factor receptors that control proliferation, migration, and survival of several cell types, including vascular endothelial cells.

Rapidly involuting congenital hemangioma: clinical and histopathologic features

We define the histopathologic findings and review the clinical and radiologic characteristics of rapidly involuting congenital hemangioma (RICH). The features of RICH are compared to the equally uncommon noninvoluting congenital hemangioma (NICH) and common infantile hemangioma. RICH and NICH had many similarities, such as appearance, location, size, and sex distribution. The obvious differences in behavior served to differentiate RICH, NICH, and common infantile hemangioma. Magnetic resonance imaging (MRI) of the three tumors is quite similar, but some RICH also had areas of inhomogeneity and larger flow voids on MRI and arterial aneurysms on angiography. The histologic appearance of RICH differed from NICH and common infantile hemangioma, but some overlap was noted among the three lesions. RICH was composed of small-to-large lobules of capillaries with moderately plump endothelial cells and pericytes; the lobules were surrounded by abundant fibrous tissue. One-half of the specimens had a central involuting zone(s) characterized by lobular loss, fibrous tissue, and draining channels that were often large and abnormal. Ancillary features commonly found were hemosiderin, thrombosis, cyst formation, focal calcification, and extramedullary hematopoiesis. With one exception, endothelial cells in RICH (as in NICH) did not express glucose transporter-1 protein, as does common infantile hemangioma. One RICH exhibited 50% postnatal involution during the 1st year, stopped regressing, was resected at 18 months, and was histologically indistinguishable from NICH. In addition, several RICH, resected in early infancy, also had some histologic features suggestive of NICH. Furthermore, NICH removed early (2-4 years), showed some histologic findings of RICH or were indistinguishable from RICH. We conclude that RICH, NICH, and common infantile hemangioma have overlapping clinical and pathologic features. These observations support the hypothesis that these vascular tumors may be variations of a single entity ab initio. It is unknown whether the progenitor cell for these uncommon congenital vascular tumors is the same as for common infantile hemangioma.

Comparison of oral pentobarbital sodium (nembutal) and oral chloral hydrate for sedation of infants during radiologic imaging: preliminary results

OBJECTIVE

The purpose of this study was to compare the safety and efficacy of oral cherry-flavored pentobarbital sodium (Nembutal) and oral chloral hydrate to sedate infants undergoing radiologic imaging.

SUBJECTS AND METHODS

We prospectively recorded data for all infants sedated with oral cherry-flavored pentobarbital sodium and oral chloral hydrate for imaging examinations between January 1997 and August 1999. The parameters recorded were each patient's age, weight, and American Society of Anesthesiologists classification; the time required to sedate; the total length of sedation time; the time required to discharge from the recovery room; and adverse events. The two-sample Student's t test and Fisher's exact test were used for statistical analysis.

RESULTS

Oral pentobarbital sodium was administered to 317 infants. These infants had a mean age +/- SD of 6.9 +/- 3.1 months and a mean weight of 7.8 +/- 4.8 kg; they received a median dose of 4 mg/kg of body weight. Oral chloral hydrate was administered to 358 infants. These infants had a mean age of 5.9 +/- 3.3 months and a mean weight of 7.3 +/- 4.9 kg; they received a median dose of 50 mg/kg of body weight. The mean time required to sedate was 19 +/- 14 min for infants receiving oral pentobarbital sodium and 16 +/- 11 min for infants receiving oral chloral hydrate (p = 0.02); the mean time required to discharge was 100 +/- 35 min for infants in the oral pentobarbital sodium group and 103 +/- 36 min for infants in the oral chloral hydrate group (p = 0.31); the mean length of sedation was 81 +/- 34 min for the oral pentobarbital sodium group and 86 +/- 36 min for the oral chloral hydrate group (p = 0.07); and median American Society of Anesthesiologists classification for both groups was P1. Oral pentobarbital sodium was inadequate for sedation in one patient (0.3%) and chloral hydrate was inadequate for sedation in another (0.3%) (p = 1.00). Adverse events were recorded for five patients (1.6%) in the oral pentobarbital sodium group and for six patients (1.7%) in the chloral hydrate group (p = 0.99).

CONCLUSION

Oral pentobarbital sodium is as safe and efficacious as oral chloral hydrate for sedating infants.

Accuracy of capnography with a 30 foot nasal cannula for monitoring respiratory rate and end-tidal CO2 in children

We tested the accuracy of a low flow (50 cc/min) sidestream capnography system equipped with an experimental 30-foot nasal cannula to monitor ventilatory status in children. End-tidal CO2 and respiratory rate, both at room air and in the presence of supplemental oxygen, were recorded simultaneously from the experimental 30-foot nasal cannula and the standard, FDA approved, 10-foot nasal cannula. The 30-foot nasal cannula was as accurate as the 10-foot nasal cannula in measuring respiratory rate and end-tidal CO2 in children. When supplemental oxygen was delivered by face-mask, there was no dilutional effect on the respiratory rate or end-tidal CO2 recorded with either the 10-foot or 30-foot nasal cannulas in place.

Fast-flow lingual vascular anomalies in the young patient: is imaging diagnostic?

AIM

To describe the imaging findings (MR imaging and angiography) of high-flow vascular anomalies of the tongue, hemangiomas and arteriovenous malformations (AVMs), with emphasis on the discrepant imaging findings in lingual AVMs.

MATERIALS AND METHODS

Retrospective review of clinical records, histologic reports and imaging studies of five consecutive patients with high-flow lingual vascular anomalies.

RESULTS

One patient had hemangioma (aged 1 month) and four patients had AVMs (aged 15 months, 6, 24, and 33 years). Diagnosis was made on the basis of histology in four lesions and was based on typical clinical history in one lesion. MR imaging and angiographic findings of the hemangioma were typical, but similar findings of focal hyperintense mass on T2-weighted images and angiographic stain were seen in three AVMs (patients aged 15 months, 6 and 33 years). On angiography, there was no nidus or direct arteriovenous (AV) shunting in one AVM (patient aged 15 months). The fourth AVM had typical MR imaging and angiographic findings.

CONCLUSION

The imaging findings in lingual AVMs can be atypical or inconclusive and can mimic hemangiomas, especially in the young patient. Since treatment depends on accurate diagnosis, biopsy may be necessary for lesions with inconclusive imaging findings.

Venous variations of the brain and cranial vault

Vascular anomalies involving both intra- and extra-cranial structures are more common than previously thought. It is important to evaluate the brain and its coverings carefully when imaging cervicofacial vascular malformations. Scientific knowledge regarding developmental mechanisms responsible for blood vessel formation is increasing rapidly and, hopefully, will contribute to better understanding of these clinical and imaging "patterns."

Angiographic features of rapidly involuting congenital hemangioma (RICH)

Rapidly involuting congenital hemangioma (RICH) is a recently recognized entity in which the vascular tumor is fully developed at birth and undergoes rapid involution. Angiographic findings in two infants with congenital hemangioma are reported and compared with a more common postnatal infantile hemangioma and a congenital infantile fibrosarcoma. Congenital hemangiomas differed from infantile hemangiomas angiographically by inhomogeneous parenchymal staining, large and irregular feeding arteries in disorganized patterns, arterial aneurysms, direct arteriovenous shunts, and intravascular thrombi. Both infants had clinical evidence of a high-output cardiac failure and intralesional bleeding. This congenital high-flow vascular tumor is difficult to distinguish angiographically from arteriovenous malformation and congenital infantile fibrosarcoma.

Venous malformations of skeletal muscle

Intramuscular venous malformations are often mistaken for tumors because of a similar presentation and improper nomenclature. This is a review of 176 patients with venous malformations localized to skeletal muscle compiled from the Vascular Anomalies Center at Children's Hospital from 1980 through 1999. The female-to-male ratio was 2:1. Two-thirds of skeletal muscle venous malformations were noted at birth; the remainder manifested in childhood and adolescence. Venous malformations occurred in every muscle group, most often in the head and neck and extremities. Pain and swelling were the usual presenting complaints. Skeletal problems, such as fracture, deformation, or growth abnormalities, were rare. Hormonal exacerbation and intralesional bleeding were infrequent. Magnetic resonance imaging showed the lesions to be isointense to surrounding muscle on T1-weighted sequences and hyperintense on T2-weighted images. Characteristic tubular or serpentine components were oriented along the muscular long axis. Thrombi were hyperintense on T1-weighted and hypointense on T2-weighted sequences; phleboliths were seen as signal voids on all sequences. Gross examination of resected specimens revealed multicolored tissue with dilated vascular channels, frequently containing phleboliths. Light microscopy showed aggregates of primarily medium-sized, thin-walled vascular channels with flat endothelium and variable smooth muscle, most closely resembling dysplastic veins. Three lesions had a different histologic appearance consisting predominantly of small vessels with capillary structure and proliferative activity admixed with large feeding and draining vessels, similar to a lesion called intramuscular capillary hemangioma in the literature. The endothelium in these three lesions was negative for glucose transporter-1 by immunostaining. Eight percent of the patients, who had minor or no symptoms, were not treated. Twenty-four percent of the patients were managed conservatively (with aspirin and compressive garments); for 17 of these patients (10 percent of 176), noninvasive therapy was not successful, and they proceeded to sclerotherapy, excision, or both. A total of 31 percent of the patients had sclerotherapy, 20 percent had excision, and 27 percent had combined sclerotherapy and excision. Sclerotherapy was used for diffuse lesions, except for those with multiple intralesional thromboses, neurologic impairment, or compressive signs and symptoms. Resection was preferred for venous malformations well localized to a single muscle or muscle group, particularly if the muscles are expendable. Therapeutic outcomes were recorded in the charts or obtained by telephone interview in 122 of the patients (69 percent). Of these, compression garment and aspirin, resection, sclerotherapy, or combined excision and sclerotherapy improved symptoms in 121 patients (92 percent); no change was noted in 10 patients (8 percent). Only one patient was worse (self-reported) after intervention.

Evolution of a protocol for ketamine-induced sedation as an alternative to general anesthesia for interventional radiologic procedures in pediatric patients

PURPOSE

To establish a protocol for credentialed pediatric radiology nurses, with radiologist supervision, to administer ketamine to induce sedation and analgesia during interventional radiologic procedures.

MATERIALS AND METHODS

This study was conducted in two phases. The goal of the first phase was to develop a sedation protocol to replace that of using general anesthesia for specified pediatric interventional procedures. Ketamine was administered intravenously (with intermittent bolus or continuous infusion) or intramuscularly. Sedation induction times, adverse events, doses, and sedation and recovery durations were recorded. In phase 2, the results of phase 1 were reviewed and a formal ketamine protocol was developed.

RESULTS

Neither sedation failures nor substantial adverse events occurred in phase 1. Mean duration of all sedations was 52 minutes, and median recovery room time was 0 minutes. In phase 2, the results of phase 1 were reviewed and a sedation protocol was proposed to a hierarchy of hospital committees before final approval from the medical staff executive committee. Subsequently, standard order forms for radiology nurse administration of ketamine with radiologist supervision were prepared for exclusive use by the pediatric interventional radiology department.

CONCLUSION

Ketamine-induced sedation may be a safe and effective alternative to general anesthesia for some interventional radiologic procedures in pediatric patients. Collaboration between anesthesia and radiology departments is important for development of a safe and successful ketamine sedation program. To the authors' knowledge, this is the first report describing the intravenous infusion of ketamine for sedation in pediatric patients and the only report describing the establishment of a protocol for ketamine administration by credentialed radiology nurses with radiologist supervision.

Outcomes of primary image-guided drainage of parapneumonic effusions in children

OBJECTIVE

To assess the outcome of image-guided needle aspiration when compared with image-guided percutaneous catheter drainage in the management of parapneumonic effusions in children.

METHODS

A retrospective chart review was conducted of the medical records, microbiology, and radiology reports of 67 children who presented with parapneumonic effusions and underwent primary image-guided drainage between April 1, 1995, and April 1, 2000.

RESULTS

Thirty-four patients had aspiration only, and 33 patients had pigtail catheters placed. The 2 drainage methods had similar median length of stay and complication rates. The reintervention rate in this study was 27% (18 patients). Children who underwent primary aspiration without catheter placement had significantly higher rates of reintervention. Method of drainage, pH lower than 7.2, and loculation of the fluid collection were independent predictors of reintervention. A low glucose level was an additive predictor of reintervention when the pH was low.

CONCLUSIONS

Aspiration and catheter drainage of parapneumonic effusions had similar complication rates and lengths of stay, but children who underwent primary aspiration had significantly higher reintervention rates, particularly when pH and glucose levels were low. Therefore, primary catheter placement for parapneumonic effusions should be considered in children who undergo diagnostic thoracentesis. The decision regarding tube placement could be facilitated by the on-site availability of a pH meter and a glucometer.

Cineangiographic aortic dimensions in normal children

Knowledge of normal aortic dimensions is important in the management of children with aortic disease. So as to define such dimensions, we undertook a retrospective review of clinical data and aortic cineangiograms from 167 subjects without aortic disease having a mean age of 3.67 years, with a range from 0.01 to 14.95 years. Amongst the patients, 56 were without detectable cardiac lesions, 66 patients had mild pulmonary stenosis, 30 were seen with Kawasaki disease, and 15 with small interatrial defects within the oval fossa. Aortograms were available in all. No patient had any hemodynamic derangement that would have affected the aorta during intrauterine life or childhood. Systolic dimensions were measured in the ascending and descending aorta at the level of the carina, at the transverse aortic arch distal to the brachiocephalic, of the left common carotid artery at its origin, at the transverse aortic arch distal to the left common carotid artery, at the aortic isthmus, and of the aorta at the level of the diaphragm. A regression analysis model was used to establish the range of predicted normal values, with their confidence limits, standardizing the values to height as the biophysical parameter having the highest correlation to aortic dimensions. Normal ranges were established for all the levels of measurement. The data should prove useful in identifying abnormalities of the thoracic aorta during childhood, and when assessing the outcomes of interventions.

The development of a pediatric radiology sedation program

BACKGROUND

An increase in the number of patients undergoing sedation for imaging procedures has led to many changes in practice over the past 10 years.

OBJECTIVE

The purpose of this study was to compare and evaluate sedation practice changes in a pediatric radiology department during the last 5 years.

MATERIALS AND METHODS

The radiology computer database and corresponding minutes of the Radiology Sedation Committee were reviewed to identify changes in sedation policy. Data from three blocks of time were analyzed to determine time to sedation, time to discharge, drug frequency, rates of adverse events, sedation failure, and paradoxical reaction.

RESULTS

Specific practice changes undertaken over the 5-year period include: (1) increased speed of administration of IV pentobarbital, (2) alternating pentobarbital and fentanyl, (3) presedation with midazolam, and (4) administering oral pentobarbital to children under and (5) over 12 months of age. Based on data analysis, changes 1 and 4 were incorporated into the sedation policy, while changes 2, 3, and 5 were abandoned. Comparison of data from the three time segments revealed improvement in the time to sedation, sedation failure, adverse event, and paradoxical reaction rates.

CONCLUSION

There is improvement in all aspects of patient outcomes with sedation, as a result of several changes in sedation practice.

Magnetic resonance of vascular anomalies

More than half of the patients with vascular anomalies referred to the Vascular Anomalies Clinic at Children's Hospital, Boston, have been misdiagnosed. A major consequence of misdiagnosis is inappropriate treatment, including deferral of necessary treatment and inappropriate use of pharmacotherapy, radiation, surgery, and embolotherapy. Hemangiomas and vascular malformations are distinct categories with completely different biologic and clinical behavior, therapeutic requirements, and imaging features. This article reviews the biologic classification of vascular anomalies and corresponding MR imaging features, and presents a simplified guide to diagnosis.

Prenatal diagnosis of vascular anomalies

BACKGROUND/PURPOSE

Vascular anomalies are diagnosed prenatally with increasing frequency. The authors reviewed a group of children treated at their center who had an abnormal prenatal diagnosis to determine (1) fetal age at which the vascular anomaly was detected, (2) general diagnostic accuracy, and (3) impact on ante- and postnatal care. Their findings are compared with reported cases and series. The authors clarify appropriate terminology and underscore the need for interdisciplinary participation of specialists in the field of vascular anomalies.

METHODS

Patients referred during prenatal life and children with a history of abnormal antenatal findings seen at our vascular anomalies center during a 1-year period (September 1999 through August 2000) were included in this study. The fetal age at diagnosis, pre- and postnatal diagnoses, antenatal course, and neonatal outcome were obtained from the parents, through chart reviews, and through telephone interviews with the treating obstetricians.

RESULTS

Twenty-nine patients with vascular anomalies were identified: 17 had a correct prenatal diagnosis, and 12 had an incorrect diagnosis, an overall diagnostic accuracy of 59%. Capillary-lymphatic-venous malformations (CLVM) most often were correctly diagnosed (67%), followed by lymphatic malformation (LM, 62%) and hemangioma (59%). In the infants who received correct diagnoses in utero, there were no fetal deaths and there was no neonatal morbidity. Maternal steroids were administered for a fetus with an intrahepatic hemangioma and deteriorating cardiac function, with subsequent stabilization and successful delivery of a healthy neonate. Among infants with incorrect diagnoses, there was 1 postnatal death, 1 case of erroneous gender assignment, 1 case of unnecessary fetal surgical intervention, 1 unnecessary neonatal laparotomy, and 1 delay in diagnosis of a malignancy. Cesarean section was done for 65% of correctly diagnosed cases, (including 2 ex utero intrapartum [Exit] procedures) and for 33% of incorrectly diagnosed cases. Most diagnoses were made during the mid- to late second trimester and third trimester; only 4 cases (14%) were detected before 20 weeks.

CONCLUSIONS

In this series, accurate diagnosis optimized antenatal care by providing an opportunity for planning deliveries, for pharmacologic fetal intervention in 1 case, and for appropriate parental counselling. Inaccurate diagnosis was associated with significantly increased morbidity and mortality. Finally, the intrauterine diagnosis of LM should be distinguished from posterior nuchal translucency, an obstetric term applied to fetal lymphatic abnormalities detected in the first and second trimesters that do not manifest as postnatal LM.

Angiographic classification of hepatic hemangiomas in infants

PURPOSE

To review the angiograms in patients with hepatic hemangiomas referred to two North American children's hospitals to determine the variability in angiographic findings and to propose a classification system that is based on these findings.

MATERIALS AND METHODS

Angiograms obtained in 15 infants with a diagnosis of hepatic hemangioma who were examined at or referred to two tertiary pediatric hospitals in North America from 1981 through 2000 were reviewed. The angiographic findings were then used to classify hemangiomas into types on the basis of a number of features, including high-flow nodules, early filling of veins, and the type of direct shunt present. Clinical data, including age at presentation, presence of cardiac insufficiency, and treatment, were also recorded.

RESULTS

Lesions were classified into five types on the basis of angiographic findings. In three of 15 patients, angiograms demonstrated the classic appearance of hepatic hemangiomas, with early filling of abnormal vascular channels, stagnation of contrast material, and no evidence of a direct shunt (type 1). In four patients, images showed high-flow nodules without direct shunts (type 2). In eight patients, direct shunts were demonstrated: arteriovenous shunts (type 3) in one, portovenous shunts (type 4) in three, and both arteriovenous and portovenous shunts (type 5) in four.

CONCLUSION

Hepatic hemangioma in infants is a heterogeneous lesion with variable angioarchitecture and a spectrum of angiographic findings.