Asymptomatic cystic changes in the brain of children after cranial irradiation: frequency, latency, and relationship to age.

Introduction: Although radiation therapy plays an important role in the management of children with brain tumors, radiation-induced brain damage sometimes occurs after radiation therapy. In some pediatric patients who had undergone cranial radiation therapy, we noticed cystic changes in the brain on follow-up MRI. The purpose of this study was to determine the frequency, latency, relationship with patient age, radiation dose, and serial change in the cystic changes in children after cranial irradiation.

Intracranial aneurysms at MR angiography: effect of computer-aided diagnosis on radiologists' detection performance.

Purpose: To retrospectively evaluate the effect of computer-aided detection (CAD) on radiologists' performance in detection of intracranial aneurysms with magnetic resonance (MR) angiography.

Materials And Methods: The institutional review board approved this study and did not require patient informed consent. Fifty maximum intensity projection MR angiograms in 50 patients were used for observer performance study.

Transthyretin-related familial amyloid polyneuropathy: evaluation of CSF enhancement on serial T1-weighted and fluid-attenuated inversion recovery images following intravenous contrast administration.

Background And Purpose: CSF enhancement on MR images after intravenous administration of gadolinium chelate, which mimics subarachnoid hemorrhage, has been reported. The purpose of this study was to determine whether CSF enhancement can be seen on serial MR images following administration of contrast material in patients with transthyretin-related familial amyloid polyneuropathy (FAP) and to assess other ancillary MR findings.

Methods: We serially studied T1-weighted and fluid-attenuated inversion recovery (FLAIR) images of the brain before, immediately after, and 3, 6, and 24 hours after contrast administration in 6 patients with genetically confirmed transthyretin-related FAP.

Retrograde cortical and deep venous drainage in patients with intracranial dural arteriovenous fistulas: comparison of MR imaging and angiographic findings.

Background And Purpose: We assessed MR imaging, specifically contrast-enhanced three-dimensional (3D) magnetization-prepared rapid gradient-echo (MP-RAGE), in evaluating retrograde venous drainage in patients with intracranial dural arteriovenous fistulas (dAVFs) that may result in catastrophic venous infarction or hemorrhage.

Methods: Twenty-one patients with angiographically proved dAVFs underwent nonenhanced spin-echo (SE) and fast SE imaging, 3D fast imaging with steady-state precession, and enhanced SE and 3D MP-RAGE imaging. Retrograde venous drainage was categorized as cerebral cortical, deep cerebral, posterior fossa medullary, ophthalmic, or spinal venous.

Quantitative evaluation of measurement accuracy for three-dimensional angiography system using various phantoms.

Purpose: The purpose of this study was to evaluate the spatial resolution and accuracy of three-dimensional (3D) distance measurements performed with 3D angiography using various phantoms.

Materials And Methods: With a 3D angiography system, digital images with a 512 x 512 matrix were obtained with the C-arm sweep, which rotates at a speed of 30 degrees/second. A 3D comb phantom was designed to assess spatial resolution and artifacts at 3D angiography and consisted of six combs with different pitches: 0.

Pseudostenosis in vessels adjacent to intracranial aneurysms on volume-rendered 3D angiograms: a phantom study.

Rationale And Objective: Among artifacts on three-dimensional (3D) angiograms, pseudostenosis in vessels adjacent to intracranial aneurysms has not been described. By using a phantom, artifacts seen in vessels adjacent to intracranial aneurysms on volume-rendered 3D angiograms were assessed.

Materials And Methods: Using a 3D angiography system and a C-arm sweep, digital images were obtained with a 512 x 512 matrix.

Evaluation of small hypothalamic hamartomas with 3D constructive interference in steady state (CISS) sequence.

Hypothalamic hamartomas are relatively rare, non-neoplastic congenital malformations. With conventional MR images alone, small hypothalamic hamartomas may be difficult to diagnose because of artifacts from cerebrospinal fluid. We present the usefulness of three-dimensional constructive interference in steady state sequence for evaluating small hypothalamic hamartomas in three pediatric patients.

Familial amyloid polyneuropathy: hypertrophy of ligaments supporting the spinal cord.

We describe characteristic spinal MR findings of two cases of familial amyloid polyneuropathy (FAP). Both cases showed leptomeningeal enhancement on contrast-enhanced T1-weighted image. In addition, three-dimensional constructive interference in steady-state imaging demonstrated thickening of the ligaments, other connective tissues within the spinal canal, dura matter, and dorsal nerve roots.

Pineal cystic germinoma with syncytiotrophoblastic giant cells mimicking MR imaging findings of a pineal cyst.

We report a case of precocious puberty in a 4-year-old boy. Contrast-enhanced T1-weighted MR imaging suggested a pineal cyst with enhancement of the slightly thickened wall and focal wall irregularity. Three-dimensional constructive interference in a steady-state imaging revealed a focal lobulation and a nodule-like area in the lesion.

Intraarterial infusion chemotherapy for head and neck cancers: evaluation of tumor perfusion with intraarterial CT during carotid arteriography.

Purpose: To evaluate drug distribution in carcinomas of the head and neck region with CT during intraarterial contrast-material injection for superselective intraarterial infusion of anti-cancer agents, and to evaluate perfusion in the carcinomas with intraarterial dynamic CT, using a combined CT and angiography system.

Materials And Methods: Twenty-three consecutive patients underwent conventional angiography as well as intraarterial injection CT using a combined CT and angiography system. Contrast material enhancement on intraarterial CT images was evaluated qualitatively and quantitatively with the following parameters: enhanced pattern, delineation and extent of tumor, peak CT value, peak time, maximum inclination of wash-in and washout, and transfer index (k) using a Patlak plot method.

Pseudostenosis phenomenon at volume-rendered three-dimensional digital angiography of intracranial arteries: frequency, location, and effect on image evaluation.

Purpose: To assess the frequency, location, and effect on image interpretation of a pseudostenosis phenomenon at volume-rendered three-dimensional (3D) digital angiography for evaluation of intracranial arteries and to determine the physical characteristics of the phenomenon by using a phantom.

Materials And Methods: Results of a total of 68 volume-rendered 3D digital angiographic examinations in 56 patients with intracranial aneurysms were retrospectively evaluated in comparison with results of digital subtraction angiography regarding the appearance of a pseudostenosis phenomenon. The phenomenon was analyzed by two radiologists in consensus with regard to frequency, location, percentage stenosis, and angle between the axis of the vessel with pseudostenosis and the axis of rotational angiography.

Clinical usefulness of unsubtracted 3D digital angiography compared with rotational digital angiography in the pretreatment evaluation of intracranial aneurysms.

Background And Purpose: Three-dimensional digital subtraction angiography (DSA) is useful as a supplement to 2D DSA in the pretreatment evaluation of intracranial aneurysms. However, the clinical efficacy of 3D digital angiography (DA) that is generated from unsubtracted rotational images has not been established. The purpose of this study was to assess whether 3D DA provides additional useful information to that of rotational DA in the preoperative evaluation of intracranial aneurysms.

Abnormal perfusion of the pituitary gland secondary to dural arteriovenous fistulas in the cavernous sinus: dynamic MR findings.

Background And Purpose: If venous congestion is the primary cause of pituitary gland enlargement in cases of dural arteriovenous fistulas (AVFs), other abnormal pituitary findings may be detectable on MR images. We sought to investigate the perfusion abnormality of the pituitary gland secondary to dural AVFs in the cavernous sinus and to clarify its clinical importance.

Methods: Nine consecutive patients (all female; age range, 50-77 years) with dural AVFs in the cavernous sinus underwent prospective MR examinations, including dynamic studies, before and after therapy.