Thymic ultrasound. I. Intrathymic anatomy in infants

BACKGROUND

The gross appearance and echogenicity of the normal thymus have been described, but specific intrathymic anatomy has not been evaluated with imaging.

SUBJECTS AND METHODS

The thymus from a 34-week-gestation stillborn male was examined with ultrasound, and the images were correlated with microscopic findings. Thymic ultrasound was performed in 12 infants without any evidence of thymic abnormality, severe infection, or chronic illness. Images were evaluated focusing on intrathymic parenchymal anatomy and compared to the liver, spleen, and thyroid gland.

RESULTS

In the specimen thymus, ultrasound demonstrated connective-tissue septa as echogenic linear structures. The cortex was relatively hypoechoic, whereas the medulla was echogenic. The blood vessels within the septa were seen as discrete echoes. In vivo ultrasound demonstrated multiple branching echogenic linear structures and foci throughout the parenchyma, representing connective-tissue septa or blood vessels within the septa. The normal thymus was easily differentiated from the liver, spleen, and thyroid glands.

CONCLUSION

Ultrasound is capable of demonstrating intrathymic anatomy, including the medulla, cortex, septa, and blood vessels in a fresh specimen. In vivo connective-tissue septa and blood vessels in the thymic parenchyma produce a unique echo pattern.

Thymic ultrasound. II. Diagnosis of aberrant cervical thymus

BACKGROUND

The aberrant cervical thymus is an uncommon entity to be considered in the differential diagnosis of neck masses in children, so a preoperative diagnosis has rarely been made.

OBJECTIVE

The purpose of this study was to assess the ultrasound features of aberrant cervical thymus and determine if recognition of the previously described unique intrathymic echo pattern allows us to make a specific diagnosis.

MATERIALS AND METHODS

We present four patients with an aberrant cervical thymus and one patient with a cervical thymic cyst. All five patients had ultrasound, which was evaluated with special attention to the detailed echo pattern of the mass. In two patients, the mass was surgically removed. Four patients had MRI, which was evaluated. Medical records were reviewed.

RESULTS

In all cases, the mass was painless and nontender. All occurred in the expected path of the thymopharyngeal duct. In four patients, ultrasound demonstrated multiple echogenic linear structures and foci previously described as characteristic echo pattern of normal thymic tissue. In one patient, ultrasound showed a large cystic mass and echogenic solid component superiorly with a characteristic echo pattern of normal thymus.

CONCLUSIONS

The ultrasound appearance of thymic tissue is unique, allowing a specific diagnosis of aberrant cervical thymus. Biopsy or other imaging is probably not indicated when it presents with typical clinical features.

Mediastinal interfaces and lines in children: radiographic-CT correlation

BACKGROUND

Various mediastinal interfaces and lines are well known in adults, but not fully understood in children.

OBJECTIVE

To review the mediastinal interfaces and lines on plain radiographs in the paediatric age group with CT correlation.

MATERIALS AND METHODS

Soft copies of 195 sets of CT examinations and concurrent chest radiographs in 180 paediatric patients (age 1 month to 15 years) were retrospectively reviewed. The frequency of visualisation and the anatomical basis of the mediastinal interfaces and lines were assessed. The evaluated mediastinal interfaces and lines were superior vena cava interface, descending aorta interface, left paraspinal interface, azygoesophageal recess interface, right paratracheal stripe, anterior junction line and posterior junction line.

RESULTS

Chest radiographs showed the SVC interface in 161, the descending aorta interface in 155, the left paraspinal interface in 98, the azygoesophageal recess in 94, the right paratracheal stripe in 53, the anterior junction line in 15 and the posterior junction line in 10. Non-visualisation of mediastinal interfaces and lines on plain radiographs was explained by normal anatomical difference compared with the adult and underlying intrathoracic abnormalities when they were correlated with CT. The frequency of visualisation of the SVC interface, descending aortic interface, left paraspinal interface and azygoesophageal recess fluctuated with age, while the frequency of the right paratracheal stripe, anterior junction line and posterior junction line increased with age.

CONCLUSIONS

Awareness of the frequency of visualisation and the anatomical basis of the mediastinal interfaces and lines in paediatric patients may be helpful for interpretation of chest radiographs.

Metabolic characteristics and prevalence of osteoporosis among women in Tae-An area

Understanding the metabolic changes in women is one of the important ways to prevent and treat osteoporosis. To reveal the metabolic characteristics of 289 healthy women aged between 35-65 yr in Tae-An, Korea we evaluated the association between bone mass assessed by broadband ultrasound attenuation (BUA) using quantitative ultrasound 2 (QUS2) and various parameters such as age, body mass index, serum levels of alkaline phosphatase, calcium, phosphorus, parathyroid hormone, 25(OH)D, and urinary ratios of calcium/creatinine and deoxypyridinoline (Dpyd)/creatinine. Among the subjects, 3.0% were osteoporotic, and 40.9% were osteopenic. When the subjects were classified according to their years since menopause (YSM) and age, the prevalence of osteoporosis increased along with an increase of YSM and age. Bone turnover markers such as serum alkaline phosphatase and fasting urinary Dpyd/creatinine were significantly higher in the group with low bone mass than in the normal group. In summary, this study shows, by use of biochemical markers of bone turnover and QUS2, the prevalence of osteoporosis in women aged between 35-65 in Tae-An was 3.0% and the risk of low bone mass increased with the bone turnover markers.

Ischemic bile duct injury as a serious complication after transarterial chemoembolization in patients with hepatocellular carcinoma

BACKGROUND

Bile duct injuries after transarterial chemoembolization (TACE) have been reported; however, the exact pathogenic mechanisms and clinical implications of the injuries remain to be clarified.

STUDY

A total of 950 consecutive patients with hepatocellular carcinoma (HCC) were studied. Among them, 807 were treated with TACE and the remaining 143 were treated with transarterial chemoinfusion (TACI) of cisplatin.

RESULTS

None of 143 patients with HCC treated with TACI were found to have any radiographic evidence of biliary injury. In contrast, of the 807 patients treated with TACE, 17 (2%) developed biliary complications. Of all complications, 12 (71%) were subcapsular bilomas; 3 (17%), focal strictures of the common hepatic duct or common bile duct; and 2 (12%), diffuse mild dilatation of the intrahepatic bile ducts. Interestingly, 2 of the 12 bilomas were found in the lobe that was not embolized with gelatin sponge particles. The median numbers of TACE tended to be greater in the patients with focal stricture than in those with bilomas (6.0 vs. 2.5; p = 0.08). All 3 patients with focal strictures and 4 of the 12 patients with bilomas had associated serious bacterial infections at presentation.

CONCLUSIONS

Bilomas seem to be caused by iodized oil rather than gelatin sponge particles; focal strictures of large bile ducts seem to be caused by gelatin sponge particles. We suggest that adjustments in the amounts of iodized oil or gelatin sponge particles and in the sites of embolization may reduce ischemic biliary injuries after TACE.

Stent-graft repair of a splenic artery aneurysm

We present a case of splenic artery aneurysm (SAA) treated with stent-grafts. This new method offers the benefit of preserving the blood flow through the splenic artery. This in turn allows for subsequent sequential embolization of the spleen when indicated, as in our patient with hypersplenism. This is the first reported case of stent-graft repair of SAA.

Use of imaging for assessing anatomical relationships of tracheobronchial anomalies associated with left pulmonary artery sling

BACKGROUND

Proper recognition, classification and assessment of the tracheobronchial anatomy are essential for surgical management planning in left pulmonary artery sling (LPAS).

OBJECTIVE

To demonstrate the various imaging modalities in diagnosing and assessing anatomical relationships with tracheobronchial tree in LPAS.

MATERIALS AND METHODS

Seven patients (three infants, three children, one adult) with LPAS were evaluated. The confirmative imaging modalities included electron-beam tomography (EBT, n = 2), MRI (n = 1) and helical CT (n = 4). Other imaging modalities included plain chest radiographs (n = 7), barium oesophagogram (n = 2), echocardiography (n = 3), cardiac and pulmonary angiography (n = 2) and bronchoscopy (n = 5).

RESULTS

There were two cases of type IA, one case of type IIA and four cases of type IIB. All five cases of type II had a long segment of tracheobronchial stenosis. A long segment of thoracic tracheal stenosis was unusually associated in one case of type IA. All confirmative modalities were sufficient for diagnosing LPAS and assessing the tracheobronchial tree anomaly. However, helical CT could not obviate angiography due to associated congenital cardiac defects.

CONCLUSIONS

Sectional imaging modalities of EBT, MRI and helical CT were all sufficient for diagnosing and assessing the anatomical relationships of the tracheobronchial tree in LPAS.

Rhabdoid tumour of the kidney: imaging findings

BACKGROUND

Rhabdoid tumour of the kidney (RTK) is a rare tumour, but it is the most aggressive malignant neoplasm of the kidney in children.

OBJECTIVE

To analyse the radiological findings of RTK in children.

MATERIALS AND METHODS

The clinical and radiological findings in seven children (age range 6 months to 4.7 years; median 18 months) with pathologically proven RTK were retrospectively reviewed. We analysed tumour size, tumour location, tumour margin, subcapsular haematoma, tumour necrosis, haemorrhage, calcification and lymphadenopathy.

RESULTS

Tumour size varied from 5 to 12 cm. Four tumours were located mainly in the central portion of the kidney, while three tumours were mainly sited peripherally. The margins of the tumour were ill-defined in four (57%) of seven cases, a lobulated tumour surface was depicted in all seven (100%), subcapsular haematoma was present in four (57%), tumour necrosis or haemorrhage in seven (100%), calcifications in three (43%) and retroperitoneal lymphadenopathy in four (57%).

CONCLUSIONS

Imaging findings of RTK are subcapsular haematoma, a lobulated surface of the tumour, calcification and tumour necrosis or haemorrhage.

Balloon dacryocystoplasty: results and factors influencing outcome in 350 patients

PURPOSE

To evaluate the initial and long-term results of balloon dacryocystoplasty in the treatment of epiphora caused by obstruction of the lacrimal system with analysis of the procedure's favorable effects.

MATERIALS AND METHODS

Four hundred thirty eyes of 350 patients with obstructions of the lacrimal system were enrolled. Dacryocystoplasty was performed with use of a balloon catheter and a ball-tipped guide wire. The lesions were categorized according to cause, severity, site of the obstruction, and diameter and inflation time of the balloon. The technical success, initial success (improvement of symptoms after 1 week), and long-term patency rates were calculated. These rates in each group were compared with the chi(2) test and the Kaplan-Meier method.

RESULTS

The overall technical success rate was 95.3%. The overall initial success rate was 57.4%. There was no significant complication except for mild epistaxis in 12%. The 2-month, 1-year, and 5-year patency rates were 48.2%, 39.4%, and 36.9%, respectively. Initial success was influenced by the severity (P =.014) and the site (P <.001) of the obstruction, and the diameter of the balloon (P =.047). Long-term patency was affected by the site of the obstruction (P <.001) and the balloon inflation time (P <.001). Among the 183 initially ineffective and 88 recurrent cases, 62 underwent repeat balloon dacryocystoplasty, and the initial success rate was 38.7%.

CONCLUSIONS

The initial success rate of balloon dacryocystoplasty is relatively low. However, long-term patency can be expected in cases with initial success. Some additional factors also should be considered for better results.

Human papillomavirus 16/18 expression of endocervical glandular lesions: relationship with p53 and MIB-1 Expressions

The pathogenesis of endocervical glandular lesions are not clearly understood. The aims of this study are to evaluate the etiologic role of human papillomavirus (HPV) 16/18 and the relationship of HPV 16/18, p53 and MIB-1 expressions in endocervical glandular dysplasia (EGD), adenocarcinoma in situ (AIS) and adenocarcinoma. The materials included 14 endocervical adenocarcinoma and 5 AIS and 18 high grade EGD and 39 low grade EGD. Immunohistochemistry for p53 and MIB-1, and in situ PCR for HPV 16/18 were done. HPV 16/18 positivity was 84.2%, 16.7% and 17.9% in malignant glandular lesion (adenocarcinoma and AIS), high grade EGD and low grade EGD, respectively. P53 protein expression rates of malignant glandular lesions, high grade EGD and low grade EGD were 31.6%, 11.1%, and 0%, respectively. High MIB-1 labelling index was found in 73.7% of malignant glandular lesions, but in only 5.7% and 3.6% of high and low grade EGD, respectively. There were statistically significant differences in HPV 16/18, p53 and MIB-1 expressions between malignant endocervical glandular lesions and EGD, but no significant difference in p53 and MIB-1 expressions in relation to HPV 16/18 expression. In malignant endocervical glandular lesions, HPV 16/18 infection may be a major causative factor, but not be related to p53 and MIB-1 expressions.

High-level expression of antimicrobial peptide mediated by a fusion partner reinforcing formation of inclusion bodies

A gene expression system for antimicrobial peptides, which could be effectively used for various studies or applications of the antimicrobial peptides, has been developed. To avoid the harmful effects on an expression host, Escherichia coli, the antimicrobial peptides were expressed as fusion proteins with a polypeptide F4, which is a truncated PurF fragment that highly tends to form inclusion bodies. Seven different kinds of antimicrobial peptides have been successfully expressed by this expression system and the resulting expression level of fusion proteins reached up to 30% of total cell proteins. To confirm the identity of the recombinant peptide, MSI-344 was selected as a model peptide and purified to homogeneity, and we could obtain the recombinant MSI-344 of a high purity and with a good yield, which was identical to the authentic peptide in the aspects of the chemical and antimicrobial properties. These results show that the neutral fusion partner, which reinforces the formation of inclusion bodies, could mediate a high-level expression of the antimicrobial peptides.

Congenital lacrimal system obstruction: treatment with balloon dilation

PURPOSE

To evaluate the safety and effectiveness of balloon dilation for the treatment of congenital lacrimal system obstruction.

MATERIALS AND METHODS

Fluoroscopically guided balloon dilation was attempted in 20 eyes of 16 patients with an age range of 12-78 months (mean, 33 mo) for congenital lacrimal system obstruction. Fifteen eyes had complete obstruction at the valve of Hasner, three eyes had completely obstruction at the junction between the lacrimal sac and the nasolacrimal duct, and two eyes had partial obstruction at the nasolacrimal duct. Under general anesthesia, a ball-tipped guide wire was introduced through the superior punctum into the inferior meatus of the nasal cavity and pulled out through the naris with use of a hook. A deflated 3-mm-diameter balloon catheter was then advanced in a retrograde direction and the balloon was dilated. Every patient underwent an ophthalmic evaluation before the procedure and was scheduled to be followed with office examination at 1, 3, and 6 months after the procedure.

RESULTS

There were no major complications. "Technical success" was defined as free passage of contrast medium through the entire lacrimal system to the nasal cavity. The procedure failed in one eye. After balloon dilation, all 19 eyes in which technical success was achieved showed improvement of epiphora. During the follow-up period of 2-33 months (mean, 16 mo), all eyes maintained improvement of epiphora and needed no further treatment.

CONCLUSION

Balloon dilation is a safe and effective therapeutic technique for the treatment of congenital lacrimal system obstruction.

Combined therapy consisting of intraarterial cisplatin infusion and systemic interferon-alpha for hepatocellular carcinoma patients with major portal vein thrombosis or distant metastasis

BACKGROUND

Hepatocellular carcinoma (HCC) patients with major vascular involvement or extrahepatic metastasis are not good candidates for surgery or transarterial chemoembolization (TACE). In this study, the authors evaluated the efficacy of combined therapy with intraarterial cisplatin infusion and systemic administration of interferon-alpha (IFN-alpha) as a palliative treatment for these patients.

METHODS

Sixty-eight HCC patients with major portal vein thrombosis (n = 47) or distant metastasis (n = 27) were randomly allocated to 1 of 3 groups. Group I (n = 19) received combined therapy consisting of intraarterial cisplatin infusion and systemic IFN-alpha, Group II (n = 23) received intraarterial cisplatin infusion, and Group III (n = 26) was managed with only supportive care. Cisplatin 2 mg/kg was infused through the proper hepatic artery every 8 weeks, and IFN-alpha 3 million IU/m2 was administered subcutaneously 3 times a week.

RESULTS

The partial response (defined as a 50% or greater reduction in the product of the 2 longest perpendicular tumor measurements) rate of Group I was significantly higher than that of Group II (33% vs. 14%; P < 0.05). Also, the 1-year survival rate of Group I (27%) was higher than that of Group II (9%) or Group III (0%) (P < 0.05 and P < 0.01, respectively). The median survival period of Group I was 19 weeks, which was significantly longer than that of Group II (11 weeks) or Group III (5 weeks) (P < 0.05 and P < 0.01, respectively).

CONCLUSIONS

These results suggest that combined therapy consisting of intraarterial cisplatin infusion and systemic IFN-alpha may be useful as a palliative treatment for HCC patients with major vascular involvement or extrahepatic metastasis.

Use of a lacrimal stent retrieval hook in the removal of occluded plastic and expandable metallic lacrimal stents

PURPOSE

To evaluate the clinical usefulness of a stent retrieval hook in the removal of occluded lacrimal stents.

MATERIALS AND METHODS

The hook consisted of an inner hook part and an outer pusher part. Under administration of local anesthetic, the retrieval hook was introduced into the nasal cavity and aimed laterally toward the inferior meatus to grasp the distal end of the stent. After grasping the end of the stent, the sheath was pushed to fully grasp it. After that, the hook was pulled out of the external naris. The retrieval hook was used to remove 267 occluded lacrimal plastic or metallic stents.

RESULTS

Technical success rate was 97% in the removal of plastic stents and 96% in the removal of metallic stents. The causes of technical failure were entrenchment of granulation tissue into the stent in six plastic stents and one metallic stent, and inaccessibility of the hook to the distal tip of the stent in one plastic stent. These eight stents were removed by an otorhinolaryngologist or an ophthalmologist. Epistaxis occurred in six patients, which was controlled by a nasal pack.

CONCLUSIONS

The lacrimal stent retrieval hook seems useful for the removal of occluded stents.

Choledochal cyst: comparison of MR and conventional cholangiography

AIMS

To assess the diagnostic value of magnetic resonance (MR) cholangiography versus conventional cholangiography in patients with choledochal cyst and to determine whether MR cholangiography can be considered an alternative to conventional cholangiography.

MATERIALS AND METHODS

Thirteen patients with choledochal cyst were examined by MR cholangiography and conventional cholangiograms. Magnetic resonance cholangiography employed T2-weighted axial and coronal fast spin-echo, single and multislab single-shot fast spin-echo sequences, including source images with maximum intensity projections. The diagnostic value of MR cholangiography and conventional cholangiograms was assessed and compared using the criteria of depiction of morphology, anomalous pancreaticobiliary duct union and demonstration of complications such as stones. A four-point diagnostic scale was applied to the delineation of the ductal anatomy with the Wilcoxon signed-ranks test and McNemar's test used for statistical analysis.

RESULTS

The depiction of the choledochal cyst was significantly better with MR cholangiography than with conventional cholangiography (P = 0.03). The detection rate of an anomalous pancreaticobiliary duct union was not significantly different with either method (P = 0.641), nor was the detection rate of bile duct stones (P = 0.375).

CONCLUSION

Magnetic resonance cholangiography provides data equivalent to or superior to those from conventional cholangiography in evaluating choledochal cyst. Magnetic resonance cholangiography is recommended as a non-invasive examination of choice for the evaluation of choledochal cyst.

Focal cortical dysplasia: comparison of MRI and FDG-PET

PURPOSE

The purpose of this work was to compare the use of MRI and [18F]fluorodeoxyglucose (FDG) positron emission tomography (PET) in the diagnosis of focal cortical dysplasia (FCD).

METHOD

Nineteen patients with surgically proven FCD were analyzed retrospectively. MRI was performed in all patients, and FDG-PET was performed in 17 patients. We compared the MR and FDG-PET findings of FCD according to the histologic findings that were classified into three grades.

RESULTS

Four cases were classified as Grade I, 4 cases as Grade II, and 11 cases as Grade III FCD. The lesions were detected on MRI in 9 (82%) of the 11 patients with Grade III FCD and in only 1 (13%) of the 8 patients with Grade I and II FCD. Cortical hypometabolism of the lesion was revealed on FDG-PET in 6 (86%) of the 7 patients with Grade I and II FCD and in 9 (90%) of the 10 patients with Grade III FCD. The extent of the cortical abnormality was larger on FDG-PET than on MRI in 11 (65%) of the 17 patients.

CONCLUSION

FDG-PET is more useful in delineating the cortical abnormality in patients with mild degrees of FCD. The extent of the lesion was larger or similar on FDG-PET compared with that of the MRI.

Pleural and pulmonary staining at inferior phrenic arteriography mimicking a tumor staining of hepatocellular carcinoma

PURPOSE

To describe the findings of pleural and pulmonary staining of the inferior phrenic artery, which can be confused with tumor staining during transarterial chemoembolization (TACE) of hepatoma.

METHODS

Fifteen patients who showed pleural and pulmonary staining without relationship to hepatic masses at inferior phrenic arteriography were enrolled. The staining was noted at initial TACE (n = 8), at successive TACE (n = 5), and after hepatic surgery (n = 2). The angiographic pattern, the presence of pleural change on computed tomography (CT), and clinical history were evaluated.

RESULTS

Draining pulmonary veins were seen in all cases. The lower margin of the staining corresponded to the lower margin of the pleura in 10 patients. CT showed pleural and/or pulmonary abnormalities in all cases. After embolization of the inferior phrenic artery, the accumulation of iodized oil in the lung was noted.

CONCLUSION

Understanding the CT and angiographic findings of pleural and pulmonary staining during TACE may help differentiate benign staining from tumor staining.

Protein tyrosine kinase inhibitors block the stimulatory actions of phosphotyrosine phosphatase inhibitors to increase cell proliferation, alkaline phosphatase activity, and collagen synthesis in normal human bone cells

The present study sought to test whether inhibition of phosphotyrosine phosphatases (PTPs) would stimulate proliferation and differentiation of normal bone cells, and whether the PTP inhibitor-mediated effects would be blocked by protein tyrosine kinase (PTK) inhibitors. Three inhibitors [phenylarsine oxide (PAO), orthovanadate (VO(4)), and molybdate (MoO(4))] and two normal human bone cells with different basal differentiation status (i.e., mandible- and vertebra-derived bone cells) were used. Cell proliferation was determined with [(3)H]thymidine incorporation, and confirmed by cell counting. Bone cell differentiation was assessed by increases in alkaline phosphatase (ALP) specific activity and collagen synthesis. The three test PTP inhibitors each stimulated [(3)H]thymidine incorporation in both human bone cell types in a biphasic, dose-dependent manner with optimal doses of 20 nM PAO, 1 microM VO(4) and 2 microM MoO(4), respectively. These PTP inhibitors at mitogenic doses each significantly and reproducibly increased ALP specific activity and collagen synthesis. To determine whether the stimulatory effects of PTP inhibitors could be blocked by PTK inhibitors, the effects of tyrphostin A51 and erbstatin, two potent PTK inhibitors, on the actions of PTK inhibitors on [(3)H]thymidine incorporation and ALP specific activity were evaluated. Both tyrphostin A51 and erbstatin, which by themselves alone significantly inhibited human bone cell proliferation and increased ALP specific activity, completely abolished the stimulatory effects of each of the three test PTP inhibitors on bone cell proliferation and ALP specific activity. In conclusion, these findings confirm the premise that inhibition of PTP activities in normal human bone cells could lead to increases in cell proliferation and differentiation, effects that are independent of basal differentiation status of the cells. More importantly, this study demonstrates for the first time that the stimulatory actions of the PTP inhibitor on bone cell proliferation and ALP could be blocked by a PTK inhibitor, suggesting that the osteogenic effects of PTP inhibitors may depend on PTK activities, presumably to increase basal tyrosyl phosphorylation level. Accordingly, one should interpret results of studies using PTK inhibitors with caution in that an inhibition by a PTK inhibitor does not necessarily indicate the requirement of PTK activities, as it could also suggest involvement of an inhibition of PTPs.

Balloon catheter dilation in common canalicular obstruction of the lacrimal system: safety and long-term effectiveness

PURPOSE

To evaluate the safety and long-term effectiveness of balloon catheter dilation in the treatment of common canalicular obstruction of the lacrimal system.

MATERIALS AND METHODS

Fluoroscopically guided dilation with a 3-mm-diameter balloon catheter was attempted in 195 eyes of 148 patients (26 men, 122 women; mean age, 57 years; age range, 33-78 years) with epiphora due to common canalicular obstruction. Eighty-four of 195 eyes had complete obstruction, and 111 had partial obstruction.

RESULTS

Complications were self-limited nasal bleeding (n = 8), false passage (n = 7), and extravasation of contrast material (n = 6). Initial technical success was achieved in 76 (90%) of 84 eyes with complete obstruction and in 104 (94%) of 111 eyes with partial obstruction. In the 180 eyes with technical success, immediate clinical improvement was achieved in 76 eyes with complete obstruction and in 100 eyes with partial obstruction. The mean follow-up period was 36 weeks (range, 4-168 weeks). The cumulative patency rates were 51% at 6-month, 43% at 12-month, and 40% at 24-month follow-up.

CONCLUSION

Although the long-term recurrence rate is relatively high, balloon catheter dilation is a safe and effective therapeutic technique to be used initially in common canalicular obstruction.

MR angiography of moyamoya disease before and after encephaloduroarteriosynangiosis

OBJECTIVE

Our purpose was to evaluate the usefulness of MR angiography in revealing moyamoya disease before and after encephaloduroarteriosynangiosis.

SUBJECTS AND METHODS

Twenty-six patients (51 hemispheres) with angiographically confirmed moyamoya disease who underwent encephaloduroarteriosynangiosis were included in the study. Findings on preoperative MR angiography were compared with those on conventional angiography. Postoperative neurologic status was categorized as poor, fair, good, or excellent. Postoperative MR angiography was examined for the appearance of the superficial temporal artery, changes in moyamoya vessels, and transdural collateral vessels into the middle cerebral artery territory.

RESULTS

Preoperative MR angiography revealed moyamoya disease in all patients (diagnostic accuracy, 100%). MR angiography correctly depicted the degree of internal carotid artery stenosis in 37 arteries (73%), moyamoya vessels in 33 hemispheres (65%), and the degree of stenosis in the middle, anterior, and posterior cerebral arteries in 125 (82%) of 153 arteries. After surgery, 39 hemispheres showed an excellent outcome, eight showed a good outcome, two a fair outcome, and two a poor outcome. On postoperative MR angiography, vascular supply to the middle cerebral artery territory via transdural collateral vessels increased in 28 hemispheres (55%) and decreased in four (8%). The size of the superficial temporal artery increased in 41 (80%) of 51 hemispheres. The extent of moyamoya vessels decreased in 27 hemispheres (53%) after surgery.

CONCLUSION

MR angiography can show the changes in the superficial temporal artery and development of transdural collateral vessels after encephaloduroarteriosynangiosis. Because MR angiography is noninvasive, it is valuable for evaluating postoperative changes.

Infantile fibromatosis in childhood: findings on MR imaging and pathologic correlation

AIM

The objective of this study was to analyse the MR imaging findings of infantile fibromatosis of childhood and to correlate them with histopathological features.

MATERIALS AND METHODS

Seven patients with histologically proven infantile fibromatosis were included in this study. The findings on MR images were retrospectively evaluated and then correlated with the pathological features. Findings on MR imaging evaluated included signal intensity, extent of hyperintense area on T2-weighted images, margins of the lesion, the degree and pattern of enhancement and the presence of fatty tissue. Pathological features evaluated included cellularity, collagenization, and myxoid change. A five point scale was used for the evaluation of the extent of hyperintense area on MR imaging, and each of pathological features.

RESULTS

On T1-weighted images, the lesions were iso-intense in two patients; iso- and hypointense in three; and iso-, hypo- and hyperintense in two. On T2-weighted images, iso-, hypo- and hyperintense areas were mixed in all patients, the hyperintense area being the largest portion of the lesion. The margins of the lesions were infiltrative in four patients (57%), smooth in two (29%) and mixed in one (14%). Enhancement was marked in five patients (72%) and diffuse in five (71%). Regardless of the hyperintense signal intensity on T2-weighted images, the grades of each pathologic feature were variable.

CONCLUSION

Infantile fibromatosis on MR imaging causes an enhancing mass, that is largely hyperintense on T2-weighted images. Areas of high signal intensity on T2-weighted images corresponded to variable grades of cellularity, collagenization, or myxoid change.

Squalene-induced extrinsic lipoid pneumonia: serial radiologic findings in nine patients

PURPOSE

The purpose of this work was to demonstrate the initial and follow-up radiologic findings of squalene-induced extrinsic lipoid pneumonia.

METHOD

Follow-up chest radiographs (n = 9) and high-resolution CT scans (n = 3) as well as initial radiographs (n = 9) and CT scans (n = 8) were obtained in nine patients with squalene-induced extrinsic lipoid pneumonia. The serial radiologic findings were analyzed retrospectively by three chest radiologists, focusing on the pattern and distribution of parenchymal abnormalities.

RESULTS

The most frequent pattern of parenchymal abnormalities on chest radiograph was areas of ground-glass opacity (n = 9, bilateral 6), followed by consolidation (n = 7, bilateral 3) and poorly defined small nodules (n = 4, bilateral 2). The abnormalities were distributed in the right lower lung (n = 9), left lower lung (n = 6), and right middle lung (n = 6) zones. Initial CT scans (n = 8) demonstrated bilateral areas of ground-glass attenuation (n = 8), poorly defined centrilobular nodules (n = 8), crazy paving (n = 6), and consolidation (n = 3). The abnormalities were distributed in the right middle lobe (n = 8) and in both lower lobes (n = 5). Follow-up chest radiograph (n = 9) showed complete disappearance (n = 2) and decrease (n = 7) in the extent of the parenchymal abnormalities. Follow-up CT scans (n = 3) demonstrated decrease (n = 2) and no change (n = 1) in the extent of the abnormalities.

CONCLUSION

Squalene-induced extrinsic lipoid pneumonia most commonly appears as areas of ground-glass attenuation mixed with poorly defined centrilobular nodules and crazy paving on CT, being distributed mainly in the right middle and both lower lobes. The lesions are indolent and remain after cessation of squalene ingestion.

Intramuscular vascular malformations of an extremity: findings on MR imaging and pathologic correlation

OBJECTIVE

To analyze the findings of intramuscular vascular malformations of an extremity on MR imaging and to correlate these findings with histopathologic examination.

DESIGN AND PATIENTS

The findings on MR imaging and the medical records of 14 patients with an intramuscular vascular malformation of the extremity were retrospectively studied. All patients underwent surgical excision. Diagnoses were based on the results of pathologic examination. Findings on MR imaging were noted and correlated with the histopathologic findings.

RESULTS

Intramuscular vascular malformations of an extremity showed multi-septate, honeycomb, or mixed appearance on MR imaging. Multi-septate areas correlated with dilated and communicating vascular spaces with flattened endothelium. Honeycomb areas corresponded to vascular spaces with inconspicuous small lumina and thickened vascular walls. Areas of increased signal intensity on T2-weighted images were found in all intramuscular vascular malformations. Infiltrative margins were more commonly seen in intramuscular lymphaticovenous malformations. Adherence to neurovascular structures and orientation of the lesion along the long axis of the affected muscle were more commonly seen in intramuscular venous malformations.

CONCLUSIONS

Intramuscular vascular malformations showed either a multi-septate, honeycomb, or mixed appearance, reflecting the size of the vascular spaces and the thickness of the smooth muscles of the vessel walls. Prediction of the subtype of an intramuscular vascular malformation of an extremity on MR imaging seems to be difficult, although there are associated findings that may be helpful in the differential diagnosis of each subtype.

MRI of primary meningeal tumours in children

Childhood meningeal tumours are uncommon and mostly meningiomas. We reviewed the histological and radiological findings in meningeal tumours in six children aged 12 years or less (four benign meningiomas, one malignant meningioma and one haemangiopericytoma). Compared to the adult counterpart, childhood meningiomas showed atypical features: cysts, haemorrhage, aggressiveness and unusual location. MRI features varied according to the site of the tumour, histology, haemorrhage, and presence of intra- or peritumoral cysts. Diagnosis of the extra-axial tumour was relatively easy in two patients with meningiomas, one malignant meningioma and one haemangiopericytoma. MRI findings strongly suggested an intra-axial tumour in two patients with benign meningiomas, because of severe adjacent edema. Awareness of the variable findings of childhood meningiomas and similar tumours may help in differentiation from brain tumours.

Hepatic falciform artery: is prophylactic embolization needed before short-term hepatic arterial chemoinfusion?

OBJECTIVE

The purpose of this study was to assess the need for prophylactic embolization of the hepatic falciform artery (HFA) to prevent supraumbilical skin rash before short-term hepatic arterial chemoinfusion with or without subsequent embolization.

MATERIALS AND METHODS

Transcatheter arterial chemoinfusions or chemoembolizations were performed on 127 consecutive patients with hepatocellular carcinoma between August 1997 and September 1997. Hepatic angiography findings regarding the anatomic variations of the hepatic artery and the presence and origin of the HFA were analyzed. The patients were followed up for 35-143 days (mean, 78 days). The incidence of supraumbilical skin rash was assessed for two groups of patients, those with an HFA and those without. We also evaluated other factors that seemed closely related to the presence of an HFA.

RESULTS

An HFA was identified in 16 (13%) of 127 patients. Each HFA originated either in the left hepatic artery (n = 14) or the middle hepatic artery (n = 2). In the 16 patients with an HFA, serum bilirubin levels were significantly higher than in patients without one (p < .05), whereas serum albumin levels and prothrombin times were significantly lower (p < .05) and more prolonged (p = .02) than in patients without one. Portal venous collateral vessels were more frequently seen in patients with an HFA (50%) than in those without one (31%), but the frequency was not significant (p = .157). However, supraumbilical skin rash was not seen in any patient.

CONCLUSION

We found no need for prophylactic embolization of the HFA to prevent supraumbilical skin rash before short-term hepatic arterial chemoinfusion with or without subsequent embolization.