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D G Spigos

Publications and source records attributed to D G Spigos.

At least 19 recordsLinked to original sources
PubMed1995

Phased array coils for upper extremity MRA.

A phased array coil was constructed for imaging the upper extremity vasculature for patients undergoing dialysis treatment. The phased array coil exhibits improved signal-to-noise ratio (SNR) over the body coil and allows imaging of the entire upper extremity. SNR as a function of depth was measured on a homogeneous phantom with the arm coil and compared with the body coil. Near the coil there is an improvement of a factor of 7 and at a depth of approximately 6-7 cm, there is an improvement of factor 2. In vivo SNR measurements resulted in similar improvements. Images of the upper extremity vasculature of healthy volunteers were generated using 2D-time-of-flight (2DTOF) angiography. Blood flow velocity was assessed in a CINE-phase contrast study.

Arm↗
PubMed1994

Renal artery pressure gradients in patients with angiographic evidence of atherosclerotic renal artery stenosis.

From October 1979 to August 1991, 231 patients underwent renal artery balloon angioplasty at The Ohio State University Hospitals. Atherosclerotic renal vascular disease was present in 171 of these patients. From this cohort, 138 patients undergoing their first angioplasty had renal artery pressure gradients performed before and after renal artery angioplasty. The demographics of this group included age 66.9 +/- 10 years (+/- SD), male 51%, white 94%, black 6%, diabetes mellitus 28%, systolic blood pressure 157 +/- 26 mm Hg, diastolic blood pressure 86 +/- 13 mm Hg, standard daily doses of antihypertensive medications 4.2 +/- 3, and serum creatinine 2.6 +/- 2.3 mg/dL. Plasma renin activity was measured in 25 patients and was shown to be elevated in 16. The renal artery stenoses were main renal artery 75%, orificial 22%, distal renal artery 1.4%, and combinations of the above 2.2%. Solitary kidneys were present in six patients (4.3%). Bilateral renal artery stenosis was present in 45% of patients and bilateral angioplasties were performed in one third of these patients. The preangioplasty systolic blood pressure gradient was 109 +/- 50 mm Hg (range, 20 to 230 mm Hg) and the postangioplasty renal artery pressure gradient was 12 +/- 16 mm Hg (range, 0 to 78 mm Hg) (P < 0.001). There were no complications related to measurement of the pressure gradients. The magnitude of the renal artery pressure gradients did not correlate with blood pressure level, number of antihypertensive medications, or serum creatinine level.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

In vivo H-1 spectroscopy in humans at 1.5 T.

Water-suppressed and section-selective proton (hydrogen-1) magnetic resonance (MR) spectra were recorded from human brain, leg muscle, liver, and heart with a 1.5-T imager. Signal from water was well suppressed, and resonances from several metabolites were consequently seen. The spectra from brains of healthy volunteers (n = 5) showed resonances from N-acetylaspartate, glutamine, aspartate, phosphocreatine/creatine, choline, taurine, and glycine. In five large brain meningiomas, resonances from N-acetyl-aspartate and phosphocreatine/creatine were either not visible or markedly decreased in intensity. The spectra from leg muscles of healthy volunteers showed resonances from protons in saturated fatty acyl chains, whereas resonances from unsaturated fatty acyl chains predominated in spectra from leg muscles of two patients with spina bifida. The spectra from livers of three healthy volunteers showed resonances from aliphatic and aromatic amino acids, choline, carnitine, and both saturated and unsaturated fatty acyl chains, and spectra from hearts of six healthy volunteers showed major resonances from phosphocreatine/creatine and taurine and smaller resonances from amino acids and fatty acyl chains.

Adipose Tissue↗
PubMed1988

Temporomandibular joint: role of direct sagittal CT air-contrast arthrogram and MRI.

Direct sagittal CT air-contrast arthrography can provide useful diagnostic information in the evaluation of disorders of the temporomandibular joint. The technique for the performance of this examination is practical and efficient, using a specifically designed head-holder, which is described. This technique effectively complements the clinical and imaging work-up of jaw dysfunction.

Adult↗
PubMed1987

Partial splenic embolisation for hypersplenism of thalassaemia major: five year follow up.

Six patients with thalassaemia major were treated by partial splenic embolisation as an alternative to splenectomy and followed up for five years. Results were compared with those in a matched control group of seven patients treated by splenectomy. All patients treated by partial splenic embolisation showed a reduction in blood transfusion requirements comparable with those in the controls and which remained unchanged over the five years. Serious infections that commonly occur in patients splenectomised for thalassaemia did not occur after embolisation, presumably owing to preservation of some immune function by the splenic remnant. By contrast with the change in platelet counts seen after splenectomy, platelet counts remained normal after partial splenic embolisation, so reducing the risk of thromboses. On the other hand, pre-existing leucopenia and thrombocytopenia were corrected after embolisation. It is concluded that partial splenic embolisation provides an alternative to splenectomy for thalassaemia major and is equally effective and much safer.

Adolescent↗
PubMed1987

Magnetic resonance imaging and intraocular foreign bodies.

We conducted in vitro and in vivo experiments to study magnetic resonance imaging of intraocular foreign bodies. Diamagnetic and paramagnetic foreign bodies were imaged without artifact and without movement during the imaging process, while ferromagnetic foreign bodies produced large amounts of artifact that prevented meaningful images. All fetromagnetic foreign bodies moved during in vitro imaging. During in vivo imaging, three of four ferromagnetic bodies moved, producing substantial retinal injury. We concluded that magnetic resonance imaging is contraindicated in traumatized eyes with suspected ferromagnetic foreign bodies.

Animals↗
PubMed1987

Surface coil holder for Signa.

A surface coil holder is described for the General Electric Signa spectrometer. This allows for accurate positioning of the 31P coil relative to that of the 1H coil used for tissue slice localization.

Arterial Occlusive Diseases↗
PubMed1987

High resolution proton magnetic resonance spectroscopy of human brain and liver.

Water-suppressed and slice-selective proton spectra of live human brain exhibited several resonances that were tentatively assigned to metabolites such as N-acetylaspartate, glutamate, phosphocreatine and creatine, choline derivatives, and taurine. In the liver spectrum of a healthy volunteer, the major resonance was tentatively assigned to a fatty acyl methylene and the minor resonances to protons in carnitine, taurine, glutamate, and glutamine. In the spectrum of a cancerous liver, resonances in addition to those present in the normal liver were seen. Protein degradation in the liver with cancer was indicated by resonances from urea and from the ring protons in tryptophan, tyrosine, and phenylalanine. Furthermore, increased nucleic acid synthesis was indicated by resonances from nucleotide protons.

Brain↗
PubMed1987

MRI of the normal orbit and optic pathway.

In recent years MRI has made increasingly important contributions to the evaluation of the orbit and optic pathway. The unique ability of MRI to demonstrate soft tissue contrast allows exquisite demonstration of anatomic detail. MRI technique and normal anatomy are reviewed. Today, optimal ophthalmologic work-up is often incomplete without the critical input of the radiologist.

Aqueous Humor↗
PubMed1986

Sciatic nerve block under fluoroscopic guidance.

Sciatic nerve block under fluoroscopic guidance was performed in 17 patients. This anesthetic technique along with femoral nerve block was found to be effective in patients having unilateral femoral arteriography or occlusive arteriography of their extremities. No complication was encountered in this group of patients.

Bupivacaine↗
PubMed1986

Subclavian aneurysm producing the subclavian steal syndrome.

An atherosclerotic aneurysm of the right subclavian artery causing subclavian steal syndrome is described. Complementary information obtained from digital subtraction angiography and computed tomography helped to establish a correct preoperative diagnosis.

Aneurysm↗
PubMed1986

Nonoperative control of retroperitoneal hemorrhage secondary to placement of an inferior vena cava occluding device in a patient with recurrent pulmonary emboli.

A woman with multiple recurrent pulmonary emboli and iatrogenic inferior vena cava perforation caused by the Hunter-Sessions introducer was treated successfully by placement of a Hunter-Sessions balloon to control the ensuing retroperitoneal hemorrhage and interrupt the inferior vena cava. Full anticoagulation therapy was continued throughout the operation and postoperatively.

Catheterization↗
PubMed1986

Arterial digital angiography in the evaluation of potential renal donors.

Twenty-two potential renal donors were examined by both arterial digital and conventional aortography. The digital studies accurately identified all of the renal arteries. Digital subtraction angiography may be a suitable alternative to conventional aortographic evaluation of the renal arterial supply of potential renal donors.

Adult↗
PubMed1986

Malignant uveal melanoma and simulating lesions: MR imaging evaluation.

Twenty-one patients with intraocular disease were studied by magnetic resonance (MR) imaging and computed tomography (CT). In 13 cases, malignant uveal melanoma was considered the likely diagnosis. Both imaging methods were accurate in determining the location and size of uveal melanomas. MR imaging was superior for the assessment of possible associated retinal detachment, for assessment of vitreous change, and for differentiating uveal melanoma from choroidal hemangioma and choroidal detachment. A case of retinal gliosis could not be differentiated from uveal melanoma by either technique. Uveal melanomas appeared as hyperintense lesions on T1-weighted images and as hypointense lesions on T2-weighted images. High signal intensity of the vitreous was observed in patients with vitritis and in those who were thought to have protein leaking into the vitreous as a result of impairment of the retinal-blood barrier.

Adult↗
PubMed1986

Regional cerebral blood flow assessment prior to balloon detachment in the treatment of intracranial giant aneurysms.

Three patients with giant aneurysms (2 internal carotid and 1 anterior communicating) were treated by internal carotid occlusion with a detachable balloon. 133Xe regional cerebral blood flow (rCBF) was performed on each patient on admission. Due to low CBF, one patient received a superficial temporal artery--middle cerebral artery (STA-MCA) bypass. The rCBF was repeated when the balloon was inflated in the internal carotid prior to detachment of the balloon. All three patients were discharged within one week with no neurologic deficit. The rCBF assessment appears useful to decide which patient will tolerate acute balloon occlusion of the internal carotid and to help select patients who will need an extra-cranial-intracranial (EC-IC) bypass to avoid ischemic complication.

Aged↗