Radiological Findings after Endoscopic Incision of Ureterocele

PURPOSE: Endoscopic incision of ureterocele is considered a simple and safe method for decompression of urinary tract obstruction above ureterocele. The purpose of this study was to evaluate the radiological findings after endoscopic incision of ureterocele. MATERIALS AND METHODS: We retrospectively reviewed the radiological findings ultrasonography (US), intravenous urography, and voiding cystourethrography(VCU)] in 16 patients with ureterocele who underwent endoscopic incision (mean age at surgery, 15 months; M: F=3:13; 18 ureteroceles). According to the postoperative results, treatment was classified as successful when urinary tract obstruction improved without additional treatment, partially successful when medical treatment was still required, and second operation when additional surgical treatment was required. RESULTS: Postoperative US (n=10) showed that in all patients, urinary tract obstruction was relieved: the kidney parenchyma was thicker and the ureterocele was smaller. Intravenous urography (n=8), demonstrated that in all patients, urinary tract obstruction and the excretory function of the kidney had improved. Postoperative VCU indicated that in 92% of patients (12 of 13), endoscopic incision of the ureterocele led to vesicoureteral reflux(VUR). Of these twelve, seven (58%) showed VUR of more than grade 3, while newly developed VUR was seen in five of eight patients (63%) who had preoperative VCU. Surgery was successful in four patients (25%), partially successful in three (19%), and a second operation-on account of recurrent urinary tract infection and VUR of more than grade 3 during the follow-up period was required by nine (56%). CONCLUSION: Although endoscopic incision of a ureterocele is a useful way of relieving urinary tract obstruction, an ensuing complication may be VUR. Postoperative US and intravenous urography should be used to evaluate parenchymal change in the kidney and improvement of urinary tract obstruction, while to assess the extent of VUR during the follow-up period, postoperative VCU is required.

Comparison of Magnetization Transfer Ratios of Various Cerebral Edemas

PURPOSE: To compare magnetization transfer ratios (MTR) among various cerebral edemas with different pathophysiologic processes. MATERIALS AND METHODS: Cerebral edemas seen on MR images in 45 patients were classified as one of three types: vasogenic (n=22; tumor[n=9], contusion[n=3], hemangioma[n=4], hemorrhage[n=4], others[2]); cytotoxic (n=18; all acute infarction), and interstitial edema (n=5). In all cases, both T2-weighted images with and without magnetization transfer were obtained using off-set pulses of 600Hz. MTRs in each cerebral edema were measured and compared. RESULTS: The mean MTRs of vasogenic edema, cytotoxic edema and interstitial edema were 22 +/- 5%, 26 +/- 4 % and 19 +/- 2%, respectively. There was no statistically significant difference among the three types (p>0.05). CONCLUSION: Mean MTR was highest in cytotoxic edema and lowest in interstitial edema, but the differences were not significant.

Diagnostic Usefulness of CT-guided Pe rcutaneous Biopsy of the Spine

PURPOSE: To evaluate the diagnostic value of CT-guided percutaneous biopsy of inflammatory and tumorous lesions of the spine and paraspinal soft tissue. MATERIALS AND METHODS: Twenty-three patients underwent CT-guided percutaneous biopsy of the spine and paraspinal soft tissue. Tentative clinical diagnoses determined before biopsy were tuberculous spondylitis (n=5), pyogenic spondylitis (n=4), butterfly vertebra (n=1), old compression fracture (n=3), discitis (n=1), hemangioma (n=1), metastasis (n=7) and multiple myeloma (n=1). Biopsy was performed at the following levels: cervical-(n=1), thoracic-(n=9), and lumbar-spine(n=13). The approach to biopsy of the spine and paraspinal soft tissue lesions was posterolateral (n=11), posterior (n=2), or transpedicular (n=10). RESULTS: Tissue considered adequate by the pathologist involved was obtained in 21 (91%) of the 23 cases. In 19 cases, pathologic findings supported the clinical diagnoses determined before biopsy. In two cases, pathologic and clinical diagnoses differed. Complications such as severe pain, bleeding, infection, neurologic deficit or damage to internal organs were detected neither during or after the procedure. CONCLUSION: CT-guided percutaneous biopsy is a safe and reliable method of obtaining a diagnosis in many cases involving different spinal and paraspinal lesions.

CT of Normal Variations of the Minute Central Skull Base Foramina

PURPOSE: To evaluate the CT appearance of normal variations in the minute central skull base foramina in infants and children. MATERIALS AND METHODS: One hundred and fourteen children under the age of 17 years without skull base abnormality underwent CT scanning. A high spatial frequency algorithm was used, and contiguous axial scanning parallel to the orbitomeatal line was performed from the foramen magnum to the orbital roof, with a 1-mm slice thickness. The presence or absence of eight foramina, pseudoforamina, or ossification centers including anterior presphenoidal foramen, posterior presphenoidal foramen, rostro-orbital pseudoforamen, intralateromedial postsphenoidal pseudoforamen, intrapostsphenoidal pseudoforamen, spheno-occipital pseudo-foramen, canalis basilaris medianus and intrasynchondral ossified bodies was analysed according to age. The presence of foramina or pseudoforamina was indicated if a ring-shaped structure was seen on two or more CT scans at the location anatomically predicted, and intrasynchondral ossified bodies were indicated if linear or dot-like structures with high attenuation accompanied spheno-occipital synchondrosis. RESULTS: CT indicated that within a certain age range, various kinds of foramina, pseudoforamina, and ossification centers were frequent. The anterior presphenoidal foramen was most commonly seen in infants aged 1-12 months (16/17, 94 %); the posterior presphenoidal foramen in children less than 2 years old(27/37, 73 % ) ; the rostro-orbital pseudoforamen in children aged 2 -5 years (9/17, 53%); intrapostsphenoidal pseudoforamen in children 6 -12 years old(20/37, 54%) and spheno-occipital pseudoforamen and intrasynchondral ossified bodies in children aged 13 -16 years. The canalis basilaris medianus was identified in about 20 % of all subjects regardless of age. CONCLUSION: Development of the minute central skull base foramina varied greatly according to age. Knowledge of the CT appearances of such embryologic variants of the central skull base should not only help Provide an understanding of complex skull base anatomy but also identify abnormal skull base development.

Usefulness of Dynamic Gadolinium-enhanced MR Imaging in Staging of Bladder Cancer

PURPOSE: To evaluate the usefulness of dynamic gadolinium-enhanced MR imaging in the staging of bladder cancer. MATERIALS AND METHODS: Twenty-four patients with histologically proven bladder cancer underwent MR imaging before tumor resection. Pre contrast axial or sagittal T1- and T2-weighted images were obtained in all patients. In 12, dynamic MR imaging was performed using the 3D-EFGRE technique in the axial plane. Images were obtained 30, 90, and 180 sec after a rapid hand injection of Gd-DTPA. T1W1, T2W1, and Gd-enhanced dynamic images were compared on the basis of lesion conspicuity and correlated with histologic specimens. The signal intensity ratio (SIR) of bladder tumors, muscle, and perivesical fat during each phase, and the contrast-to-noise ratio (CNR) of lesion-to-muscle and lesion-to-fat were determined. RESULTS: The accuracy of tumor staging using both T1WI and T2WI was 38% (9/24), and the accuracy of dynamic gadolinium enhanced MR imaging was 58% (7/12). The difference was statistically significant (p<0.05). The SIR of tumors was highest during the capillary phase, and decreased during the venous phase. During all phases i t was significantl y higher than that of bladder muscle and perivesi cal fat ( P < 0.05). The CNR of tumor-to-muscle and tumor-to-perivesical fat increased abruptly during the arterial phase, was highest during the capillary phase and decreased slightly during the venous phase. CONCLUSION: Dynamic gadolinium enhanced MR imaging improves the diagnostic accuracy of both T1WI and T2WI in the preoperative staging of bladder cancer and can be useful in the management and estimation of prognosis. For evalvation of the staging of bladder cancer, the capillary phase is optimal.

Usefulness of Dynamic Gadolinium-enhanced MR Imaging in Staging of Bladder Cancer

PURPOSE: To evaluate the usefulness of dynamic gadolinium-enhanced MR imaging in the staging of bladder cancer. MATERIALS AND METHODS: Twenty-four patients with histologically proven bladder cancer underwent MR imaging before tumor resection. Pre contrast axial or sagittal T1- and T2-weighted images were obtained in all patients. In 12, dynamic MR imaging was performed using the 3D-EFGRE technique in the axial plane. Images were obtained 30, 90, and 180 sec after a rapid hand injection of Gd-DTPA. T1W1, T2W1, and Gd-enhanced dynamic images were compared on the basis of lesion conspicuity and correlated with histologic specimens. The signal intensity ratio (SIR) of bladder tumors, muscle, and perivesical fat during each phase, and the contrast-to-noise ratio (CNR) of lesion-to-muscle and lesion-to-fat were determined. RESULTS: The accuracy of tumor staging using both T1WI and T2WI was 38% (9/24), and the accuracy of dynamic gadolinium enhanced MR imaging was 58% (7/12). The difference was statistically significant (p<0.05). The SIR of tumors was highest during the capillary phase, and decreased during the venous phase. During all phases i t was significantl y higher than that of bladder muscle and perivesi cal fat ( P < 0.05). The CNR of tumor-to-muscle and tumor-to-perivesical fat increased abruptly during the arterial phase, was highest during the capillary phase and decreased slightly during the venous phase. CONCLUSION: Dynamic gadolinium enhanced MR imaging improves the diagnostic accuracy of both T1WI and T2WI in the preoperative staging of bladder cancer and can be useful in the management and estimation of prognosis. For evalvation of the staging of bladder cancer, the capillary phase is optimal.

Nasal Bone Fractures : Evaluation with Thin-section CP

PURPOSE: To determine the value of thin-section CT in the diagnosis of nasal bone fractures. MATERIALS AND METHODS: We evaluated the thin-section CT scans of 40 patients with nasal bone fracture. CT scans were obtained with both axial and coronal planes, 1.5mm collimation with 2mm interval, and 9.6cm field-of-view. The axial scan plane was kept parallel to the orbitomeatal line from the nasion to the lower limit of the nose and the coronal plane was kept perpendicular to the axial plane. The data were reconstructed with bone algorithm. Nasal bone fracture was classified into 1 of 3 types on thin section CT:(I) simple fracture;(ll) simple fracture with displacement;(III) comminuted fracture. Associated facial bone injuries were also evaluated Simple radiographs of nasal bone were reviewed for comparison. RESULTS: Six patients had simple fracture, 10 patients had simple fracture with displacement, and 24 patients had comminuted fracture. Twenty-six patients had associated facial bone injuries which included fracture of nasal septum (n=15), fracture of frontal process of maxilla (n=9), fracture of ethmoid (n=6), widening of nasofrontal suture (n=5), and fracture of nasolacrimal duct (n=2). In 15 of 40 patients, CT could identify nasal bone fractures not detected on simple radiographs. CONCLUSION: Thin-section CT is a valuable aid in the evaluation of nasal bone fracture for accurate identification, nature, and combined facial injury.

CT Findings of Palpable Neck Masses in Children

PURPOSE: We performed this study to assess the value of CT in the differential diagnosis of palpable neck masses in children. MATERIALS AND METHODS: We retrospectively reviewed the CT scans of the palpable neck masses in 30 children. The masses were proved histopathologically and classified into cystic, solid, and inflammatory mass and their CT findings were analyzed. RESULTS: Twelve cases were cystic masses, 4 were solid masses, and 14 were inflammatory lesions. Cystic masses included cystic lymphangiomas (n=6), branchial cleft cysts (n=3), thyroglossal duct cysts (n=2), and ranula (n=l). Cystic lymphangiomas showed insinuating appearances into adjacent structures and 4 cases occurred in the posterior cervical space. All branchial cleft cysts were round cystic masses with smooth wall and displaced the submandibular gland anteriorly and the sternocleidomastoid muscle posteriorly. Two thyroglossal duct cysts occurred centrally adjacent to the hyoid bone and 1 ranula in the submental area. Solid masses were juvenile hemangioma, pleomorphic adenoma in submandibular gland, neurilemmoma, and fibromatosis colli. Juvenile hemangioma showed well-enhancing mass with indistinct margin and the other solid masses had well-defined margin with their characteristic location. Inflammatory lesions were abscess (n=4), deep neck infections with lymphadenopathy (n=4), submandibular gland inflammation (n=3), and tuberculous lymphadenitis (n=3) and they showed strand-like enhancement in adjacent subcutaneous tissues. Tuberculous lymphadenitis had multiple lymph node enlargement with internal low attenuation areas and showed less surrounding strand-like enhancement than suppurative lymphadenopathies. CONCLUSION: Most neck masses in infants and children were of congenital or inflammatory origin. CT is useful for the evaluation of the child presenting with a neck mass, because it can differentiate various forms of neck masses and is able to reveal the relationship of the masses to the adjacent structures with their characteristic location.

Branchial Cleft Anomalies: CT Evaluation

PURPOSE: The purpose of this paper is to describe the CT findings of a variety of branchial cleft anomalies in the head and neck area. MATERIALS AND METHODS: We reviewed the CT findings of 16 patients with neck lesion pathologically proved as branchial cleft anomalies. There were two first and 12 second branchial cleft cysts, one first and one second branchial cleft sinuses. RESULTS: Two cases of first branchial cleft cysts were manifested as thin walled, cystic masses at auricular area. One first branchial cleft sinus was an external opening type and manifested as an ill defined, enhancing solid lesion at posterior auricular area. All 12 cases of second branchial cleft cysts demonstrated a typical location, displacing the sternocleidomastoid muscle posteriorly, the carotid artery and internal jugular vein complex medially and the submandibular gland anteriorly. Eight cases of second branchial cleft cysts were seen as fluid-filled, round or ovoid shaped cysts, and 3 cases of them were seen as irregular-shaped cysts. In one case. suppurative adenopathy with loss of soft tissue planes around the cyst was observed. One case of second branchial cleft sinus was manifested as a tubular-shaped, enhancing lesion at submental area and containing external opening site draining into the anterior border of the sternocleidomastoid muscle. CONCLUSION: We conclude that CT provides important diagnostic and therapeutic informations in patients with a neck mass believed to be a branchial cleft anomaly, as it can differentiate various forms of the branchial anomalies by their characteristic location and shape.