Relationship between intracranial aneurysms and the severity of autosomal dominant polycystic kidney disease.

Background: Autosomal dominant polycystic kidney disease (ADPKD) is a hereditary kidney disease characterized by the progressive enlargement of innumerable renal cysts. Although the association of intracranial aneurysms (ICANs) with ADPKD is well known, the relationship between the ICAN and the disease severity including total kidney volume (TKV) and estimated glomerular filtration rate (eGFR) is poorly understood.

Methods: We screened 265 patients with ADPKD (mean age, 48.

Kidney volume estimations with ellipsoid equations by magnetic resonance imaging in autosomal dominant polycystic kidney disease.

Background: Kidney volume (KV) becomes clinically relevant in autosomal dominant polycystic kidney disease (ADPKD) management. KV can be conveniently estimated (ceKV) using ellipsoid volume equations with three axes measurements; however, the accuracy and reliability are unknown.

Methods: KVs of 347 kidneys in 177 consecutive ADPKD patients were determined with a volumetric method (standard-KV), and ceKV was calculated using six different ellipsoid equations with three axes measurements using magnetic resonance imaging.

Non-contrast myocardial perfusion using a novel 4D magnetic resonance arterial spin labeling technique: initial experience.

The aim of this study is to develop a novel non-contrast 4-dimensional MR arterial spin labeling (4D-ASL) technique (3D acquisition and time) and to investigate myocardial perfusion on healthy volunteers without administration of contrast materials. A non-contrast 4D-ASL technique was developed using the time-spatial labeling inversion pulse (Time-SLIP) to obtain myocardium perfusion of eight volunteers at 1.5 T.

Safety study of somatostatin analogue octreotide for autosomal dominant polycystic kidney disease in Japan.

Background: The total kidney volume (TKV) and total liver volume (TLV) increase and renal function decreases progressively in patients with autosomal dominant polycystic kidney disease (ADPKD). Somatostatin analogues, such as octreotide, reduce these increases in TKV and TLV. The aim of this study was to examine the safety of the short-term administration of octreotide long-acting release (octreotide-LAR) in a small number of cases.

Clinical application of an automatic slice-alignment method for cardiac MR imaging.

Purpose: We evaluated the usefulness of an automatic slice-alignment method to simplify planning of cardiac magnetic resonance (MR) scans with a 3-tesla scanner.

Methods: We obtained 2-dimensional (2D) axial multislice images using steady-state free precession (SSFP) sequences covering the whole heart at the end-diastole phase with electrocardiography (ECG) gating in 38 patients. We detected several anatomical feature points of the heart and calculated all planes required for cardiac imaging based on those points.

Does increased water intake prevent disease progression in autosomal dominant polycystic kidney disease?

Background: The clinical effects of increased water intake on autosomal dominant polycystic kidney disease (ADPKD) progression are unknown.

Methods: ADPKD patients with creatinine clearance ≧ 50 mL/min/1.73 m(2) were divided into high (H-, n = 18) and free (F-, n = 16) water-intake groups, mainly according to their preference.

Postoperative evaluation of superficial temporal artery-middle cerebral artery bypass using an MR angiography technique with combined white-blood and black-blood sequences.

Purpose: To assess the performance of the hybrid of opposite-contrast MR angiography (HOP MRA) technique, which combines flow dephasing and compensating sequences, in the postoperative evaluation of superficial temporal artery (STA)-middle cerebral artery (MCA) bypass.

Materials And Methods: Both 3D-HOP MRA and 3D-time-of-flight (TOF) MRA at 1.5 Tesla were performed in 19 patients after STA-MCA bypass.

Automatic slice alignment method for cardiac magnetic resonance imaging.

Objectives: Automatic slice alignment is important for easier operation and shorter examination times in cardiac magnetic resonance imaging (MRI) examinations. We propose a new automatic slice alignment method for six cardiac planes (short-axis, vertical long-axis, horizontal long-axis, 4-chamber, 2-chamber, and 3-chamber views).

Materials And Methods: ECG-gated 2D steady-state free precession axial multislice images were acquired using a 1.

Whole-heart 3D late gadolinium-enhanced MR imaging: investigation of optimal scan parameters and clinical usefulness.

Purpose: Whole-heart 3-dimensional (3D) late-gadolinium-enhanced magnetic resonance (MR) imaging (WH-LGE) uses respiratory gating combined with acquisition of 3D data for the entire heart in a single scan, which permits reconstruction of any plane with high resolution. We investigated the optimal scan parameters and compared WH-LGE with the conventional scanning method.

Materials And Methods: We employed inversion recovery 3D fast field echo using a 1.

Rupture of pseudoaneurysm of the pancreaticoduodenal arcade after acute aortic dissection in a patient on anticoagulant therapy.

An 81-year-old woman on anticoagulant therapy after mechanical heart valve replacement was admitted because of acute aortic dissection. Anticoagulant therapy had to be continued with heparin even after admission. Gastrointestinal hemorrhage occurred suddenly and she developed hemorrhagic shock.

Hybrid of opposite-contrast magnetic resonance angiography of the brain by combining time-of-flight and black blood sequences: its value in moyamoya disease.

Objective: We assessed the value of a new magnetic resonance angiography (MRA) technique named hybrid of opposite-contrast (HOP) MRA in the diagnosis of moyamoya disease.

Methods: Using a dual-echo sequence, we obtained the first echo for time-of-flight (TOF) MRA followed by the second echo for black blood MRA. We then subtracted the black blood MRA data set from that of the TOF MRA followed by maximum-intensity projection.

Hybrid of opposite-contrast MRA of the brain by combining time-of-flight and black-blood sequences: initial experience in major trunk stenoocclusive diseases.

Purpose: To assess the feasibility of a new MR angiography (MRA) technique named hybrid of opposite-contrast MRA (HOP MRA) that combined the time-of-flight (TOF) MRA with a flow-sensitive black-blood (FSBB) sequence in the diagnosis of major trunk stenoocclusive diseases.

Materials And Methods: On a 1.5 Tesla imager using a dual-echo three-dimensional (3D)-gradient-echo sequence, we obtained the first echo for TOF MRA followed by the second echo for FSBB.

CT angiography covering both cervical and cerebral arteries using high iodine concentration contrast material with dose reduction on a 16 multidetector-row system.

Introduction: Our aim was to examine the feasibility of a computed tomographic angiography (CTA) protocol using a reduced dose of high-concentration contrast material on a 16 multidetector-row system to visualize both cervical and cerebral arteries in one session.

Methods: In 31 consecutive patients, we performed CTA covering the cervical and cerebral arteries. The patients were assigned to one of three groups: group A, 100 mL of 300 mgI/mL; group B, 80 mL of 370 mgI/mL; and group C, 60 mL of 370 mgI/mL followed by a 30-mL saline flush.

CT Angiography Covering Both Cervical and Cerebral Arteries on a 16-Detector Row System: Modification of Contrast Dose and Injection Rate by Patient Weight.

We assessed the feasibility of modifying the contrast dose and injection rate based on patient weight in four patient groups in whom CT angiography was performed with contrast agent 350 mgI/mL at different injection doses in combination with a saline flush (40 mL). Patients were assigned to one of four groups: group A: injection dose (ID) of 1.3 mgI/kg; group B: ID of 1.

CT Angiography Covering Both Cervical and Cerebral Arteries Using Contrast Material with a Reduced Dose and Higher Concentration on a 16-Detector Row System: Effect of the Iodine Delivery Rate and a Saline Flush.

We assessed the effect of iodine delivery rates (IDRs) and a saline flush in CT angiography that covered both cervical and cerebral arteries when a contrast material of higher concentration (350 mgI/mL) was employed. In three patient groups whose CT angiography was performed at different IDRs with or without a saline flush, we measured the attenuation of target vessels and visually evaluated the images obtained. Our results indicated that a higher IDR was effective to increase the attenuation value of both cervical and cerebral arteries without changing that of the venous system, although it did not significantly affect visualization of these vessels.

Cerebral CT angiography using a reduced dose of contrast material at high iodine concentration in combination with a saline flush.

Aim: To determine whether cerebral computed tomography (CT) angiography with a 16-detector row system can be performed using a reduced dose of contrast material.

Materials And Methods: Twenty-eight patients were assigned to one of four protocols: A=50 ml of 350 mg I/ml with a saline flush (SF, 40 ml); B=75 ml of 350 mg I/ml with an SF; C=75 ml of 350 mg I/ml without an SF; and D=100ml of 300 mg I/ml without an SF. The attenuation of the internal carotid, middle cerebral, and anterior cerebral arteries were measured.

Demonstration of spinal cord and nerve root abnormalities by diffusion neurography.

Objective: Diffusion-weighted magnetic resonance imaging postprocessed by maximum-intensity projection reportedly demonstrates the nerve roots. We modified this technique using a fluid-attenuated inversion-recovery-based diffusion-tensor scan using parallel imaging and evaluated its feasibility in demonstrating spinal cord and nerve root abnormalities.

Methods: We applied this technique to 18 patients with miscellaneous pathological conditions that included multiple sclerosis, chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), neurofibromatosis (NF), schwannoma, cord injury, and tethered cord.

Diffusion tensor tractography of the lower spinal cord.

Introduction: We employed a diffusion-tensor (DT) imaging technique involving a single-shot echo-planar sequence in combination with parallel imaging for tractography of the lower spinal cord and assessed the feasibility of this technique.

Methods: Images were obtained at 1.5 T using a five-channel receiver coil.

Optimal diagnostic criteria for lateral pelvic lymph node metastasis in rectal carcinoma.

Aim: The purpose of this study was to determine the optimal diagnostic criteria for lateral pelvic lymph node metastasis in patients with rectal carcinoma.

Patients And Methods: From July 1997 to June 2005, fifty-one patients with locally advanced middle or lower rectal carcinoma underwent preoperative MRI examination, followed by total mesorectal excision with lateral pelvic node dissection. Factors of lateral pelvic lymph nodes evaluated were size, shape and internal structure.

Neurography of the spinal nerve roots by diffusion tensor scanning applying motion-probing gradients in six directions.

Purpose: Diffusion-weighted (DW) magnetic resonance (MR) imaging of the nerve roots and peripheral nerves has been reported. We applied a sequence similar to brain diffusion tensor (DT) tractography to such a technique and assessed its feasibility.

Methods: On a 1.

Comparison of MRI sequences to detect ventriculitis.

Objective: The ability of different MRI sequences to depict characteristic findings suggestive of ventriculitis was compared.

Conclusion: The study comprised 20 brain MRI studies in 13 patients who had a final diagnosis of ventriculitis. Both diffusion-weighted imaging and FLAIR imaging were equally and highly sensitive for detecting intraventricular debris and pus--the most common MRI finding suggestive of ventriculitis.

Value of diffusion-weighted MR imaging in acute cervical cord injury as a predictor of outcome.

Introduction: We analyzed the findings of diffusion-weighted (DW) imaging using the single-shot fast spin-echo sequence in acute cervical cord injury and evaluated the usefulness of this method for predicting the prognosis.

Methods: Our patient group comprised 14 patients examined 2 h to 3 days after injury. First, we visually evaluated the DW imaging findings in all patients.

Visualization of cervical nerve roots and their distal nerve fibers by diffusion-weighted scanning using parallel imaging.

Purpose: To report a technique developed for visualizing cervical nerve roots and distal nerve fibers using diffusion-weighted magnetic resonance imaging employing parallel imaging.

Material And Methods: We performed maximum intensity projection for a stack of isotropic axial diffusion-weighted images obtained with parallel imaging applying a motion-probing gradient in six directions with a b-value of 500 s/mm2 in a preliminary series of 13 subjects.

Results: This method worked well for visualizing the spinal cord and most of the nerve roots, the dorsal root ganglia, and proximal peripheral nerves.

Efficacy of cardiac MRI in the evaluation of ischemic heart disease.

With the development of fast scan techniques and technical advances in software, cardiac MRI can now be used for morphological and functional evaluation of the heart with good reliability and high spatial and temporal resolution. Cardiac MRI is employed at many institutions, mainly for assessing ischemic heart disease. Cardiac MRI can be used to identify coronary artery stenosis, evaluate myocardial viability, assess left ventricular wall motion and function, measure coronary blood flow and flow reserve, and obtain other useful information for the diagnosis of ischemic heart disease in a single examination, serving as a true comprehensive cardiac study.