Biomedical subjects

P F New

Publications and source records attributed to P F New.

At least 19 recordsLinked to original sources

PubMed1988

Use of magnetic resonance imaging in psychiatry.

The authors report four cases in which magnetic resonance imaging (MRI) provided diagnostic information not apparent by X-ray CAT in clinical investigations of patients with neuropsychiatric disorders. The relative capabilities and contraindications for MRI and CAT are reviewed. The authors suggest that MRI is indicated 1) instead of CAT when there is suspicion of neuropathology that is better visualized by MRI because of its type or location and 2) after CAT when an atypical psychiatric symptom or presentation has not been definitively evaluated by means of CAT.

Aged↗

PubMed1988

The role of MR and CT in evaluating clival chordomas and chondrosarcomas.

Sixteen chordomas and nine chondrosarcomas of the clivus were evaluated with CT and MR either before (22 cases) or after (three cases) treatment with proton beam irradiation. The ability of these imaging techniques to provide information necessary to direct patient treatment was studied. The tumor was detected and its gross margins were identified by both techniques in all instances. No reliable diagnostic features allowing differentiation between these two tumors were encountered. MR generally was superior in defining the exact position of the brainstem and optic chiasm relative to the tumor, and it frequently provided superior information about tumor extension into the nasopharynx and cavernous sinus. CT was always better than MR in demonstrating tumoral calcification and in defining the exact anatomy of bone destruction. MR was generally superior to CT in demonstrating the position of the cavernous internal carotid artery relative to the tumor and often provided superior visualization of the vertebral and basilar arteries. In cases in which bone-induced artifact obscured the interface between the neural axis and tumor in the CT image, or in which the tumor had suprasellar extension and was likely to compress the optic chiasm and tracts, MR was of great value in planning irradiation therapy. The high occurrence of clinically asymptomatic signal intensity alterations in the MR studies of previously treated patients appears to limit the differential diagnostic value of this information. Given its greater availability and lower cost, CT appears to be the technique of choice for routine follow-up of previously treated patients.

Adolescent↗

PubMed1988

Angiographically occult arteriovenous malformations.

Eight cases of histopathologically proven arteriovenous malformations (AVM's) which were not visualized on angiography are presented. As is typical with these lesions, most of the patients in this series presented with hemorrhage, seizures, or episodic or progressive neurological symptoms suggestive of a neoplasm. The diagnosis of angiographically occult AVM was highly suspected preoperatively in each case based on the combination of computerized tomography (CT) and magnetic resonance (MR) findings. The CT scans in all cases showed moderately hyperdense lesions which enhanced mildly or moderately in a nonhomogeneous pattern with administration of contrast material. The MR image showed one or more bright areas interspersed with areas of low or absent signal peripherally or centrally on both T1- and T2-weighted images. The AVM was totally excised in seven patients and partially excised in one patient, with favorable results in all. The clinical management and differential diagnosis of angiographically occult AVM's are discussed. In patients with a clinical course and radiological studies suggestive of an occult AVM, removal of the lesion, if accessible, should be performed in order to rule out a neoplasm and prevent subsequent hemorrhage and progression of symptoms.

Adolescent↗

PubMed1986

MR and CT of occult vascular malformations of the brain.

The need for improved specificity in the diagnosis of "occult" vascular malformations led to the use of MR in suspected cases in order to determine MR's potential for improved diagnostic accuracy. Six patients with six lesions histologically diagnosed as vascular malformation after partial (1) or complete (5) microsurgical excision were studied by CT, MR, and selective magnification subtraction angiography. In all cases, the cerebral lesions were apparently solitary and were visible as focal lesions on both CT and MR. Since angiography failed to reveal the pathologic blood vessels of the lesions, and no arteriovenous shunting was evident, these lesions were termed vascular malformations occult to angiography (VMOTA). Angiography revealed a mass effect in only two cases. MR did not reveal additional vascular malformations missed by CT. In each case, MR, which was performed in an attempt to support the diagnosis suggested by CT, did in fact do so by revealing signal abnormalities indicative of nonacute hemorrhage within the lesion on T1- and T2-weighted pulse sequences. Although, as on CT, MR features of these lesions were found to be nonspecific, the MR criteria reinforced the probable diagnosis of VMOTA in an additional 30 cases that had shown similar nonspecific CT features. In this second group, excluded from this study, in which histologic verification was not obtained because of perceived hazards of surgery, the increased assurance regarding the diagnosis led to proton-beam therapy without histologic verification in 18 cases. It is concluded that MR can provide significant improvement in the accuracy of diagnosing VMOTA beyond that obtainable just by plain and contrast-enhanced CT.

Adult↗

PubMed1986

Magnetic resonance imaging of the thoracical spinal cord and spine with surface coils.

We report the results obtained at 0.6 T with the use of surface coils in 77 patients who presented with obvious or suspected thoracic myelopathy. There were 16 patients with primary tumors diagnosed for the first time, 9 patients with residual tumors, 17 with metastatic neoplasms, 13 with hydrosyringomyelia, 5 with vertebral fracture and secondary pathology involving the cord, 5 with thoracic disc protrusions, 2 with multiple sclerosis, 2 with arteriovenous malformations, 2 with cystic arachnoiditis, and 6 with a variety of congenital abnormalities (low tethered cord, intradural lipoma, lipomyelomeningocele). The significantly improved signal to noise ratios provided by surface coils allow high quality thin section imagning which, combined with the high tissue contrast resolution obtainable with suitable pulse sequences, makes MR the preferred initial imaging technique over myelography and CT myelography. In an interesting spectrum of lesions, MR can obviate the need for traditional invasive procedures.

Adolescent↗

PubMed1985

Magnetic resonance imaging: present and future applications.

Magnetic resonance (MR) imaging has created considerable excitement in the medical community, largely because of its great potential to diagnose and characterize many different disease processes. However, it is becoming increasingly evident that, because MR imaging is similar to computed tomography (CT) scanning in identifying structural disorders and because it is more costly and difficult to use, this highly useful technique must be judged against CT before it can become an accepted investigative tool. At present MR imaging has demonstrated diagnostic superiority over CT in a limited number of important, mostly neurologic, disorders and is complementary to CT in the diagnosis of certain other disorders. For most of the remaining organ systems its usefulness is not clear, but the lack of ionizing radiation and MR's ability to produce images in any tomographic plane may eventually prove to be advantageous. The potential of MR imaging to display in-vivo spectra, multinuclear images and blood-flow data makes it an exciting investigative technique. At present, however, MR imaging units should be installed only in medical centres equipped with the clinical and basic research facilities that are essential to evaluate the ultimate role of this technique in the care of patients.

Abdomen↗

PubMed1985

MR imaging of the acoustic nerves and small acoustic neuromas at 0.6 T: prospective study.

To evaluate the capability of magnetic resonance (MR) in imaging normal acoustic nerves, 12 volunteers without signs or symptoms of intracranial disease were examined using a 0.6 T superconductive system. Several spin-echo (SE) pulse sequences were tested to identify the optimal sequence for demonstration of the acoustic nerve bundle. Repetition times (TRs) varied from 300 to 2000 msec and echo times (TEs) from 30 to 120 msec. A single-slice technique was used with 5 and 8 mm sections, one or two data acquisitions per projection, and axial and coronal imaging. The normal acoustic nerves were demonstrated readily by MR in axial and/or coronal sections. The distal parts of the nerves and tumors were imaged best with SE 1500/60. The medial extremities of the seventh and eighth nerves tended to be obscured in this sequence by brightening the cerebrospinal fluid signal adjacent to the brainstem, but they were demonstrated clearly with 500 or 800 msec TR and 30 msec TE. Five patients were studied who had hearing loss and evidence of retrocochlear disease. In four patients, MR imaging demonstrated five acoustic nerve tumors ranging in size from purely intracanalicular to a 12 mm cisternal component. In the fifth case, no tumor was identified by MR imaging or gas computed tomographic (CT) cisternography. Contrast-enhanced CT using a Siemens Somatom DR 3 or GE CT/T 8800 scanner failed to provide convincing evidence of tumor in any case, while gas CT cisternography was positive in all five tumors. All five acoustic neuromas were identified readily using the SE sequences that proved optimal for demonstration of normal nerves. This experience revealed that MR imaging can demonstrate the eighth nerve complex well and reliably. Single-slice (5 or 8 mm) technique is adequate, but multislice without tissue gaps (used recently) is more efficient. Small, even intracanalicular, acoustic neuromas are imaged effectively, indicating that the method is capable of superseding contrast CT cisternography, particularly with improving technology.

Atrophy↗

PubMed1985

High-resolution surface-coil imaging of lumbar disk disease.

Seventeen patients with lumbar disk disease were studied using a prototype magnetic resonance (MR) surface coil. The high signal-to-noise ratio achieved with the surface coil permitted increases in spatial resolution to 0.9 X 0.9 mm in-plane resolution with 5 mm slice thickness. The surface coil was also compatible with multiplanar, multiecho imaging techniques. The spatial resolution achieved in this study was nearly equivalent to that achieved by state-of-the-art computed tomographic (CT) scanners, and MR showed a superior range of soft-tissue contrast. One significant limitation of MR was its inability to demonstrate small calcifications. Nevertheless, MR imaging provided diagnostic information comparable to CT or myelography in a completely noninvasive manner. With further technical advances, MR is likely to become the initial procedure of choice for evaluating patients with suspected lumbar disk disease.

Humans↗

PubMed1979

Evaluation of mucoceles of the paranasal sinuses with computed tomography.

Eighteen patients with mucoceles of the paranasal sinuses were studied by plain radiography, pluridirectional tomography, and computed tomography (CT). Sixteen of the lesions had a homogeneous appearance on CT but demonstrated variable absorption characteristics, with acutely infected mucoceles showing rim enhancement. Plain radiography and pluridirectional tomography were usually sufficient for making a diagnosis and defining the extent of the lesion, but CT more accurately demonstrated orbital and intracranial extension. Both transverse and coronal CT are essential for adequate evaluation.

Adolescent↗

PubMed1978

Computed tomography of the orbit with special emphasis on coronal sections.

Computed tomography (CT) is an extremely valuable noninvasive method for evaluating orbital soft-tissue structures. The possibility of scanning in the coronal plane has added a new dimension to the study. Direct enlargement viewing of scans on the display console has disclosed minute anatomic and pathologic details.

Humans↗

PubMed1978

Orbital fracture evaluation by coronal computed tomography.

Coronal computed tomography produces orbital scans in a plane that is analogous to Caldwell-view x-ray films. Coronal computed tomography permits simultaneous visualization of the orbital walls and the orbital soft tissues, including all extraocular muscles. Using coronal computed tomography, we studied a series of patients with radiographically proven orbital floor fractures. We studied in detail three of these patients, one with a linear orbital floor fracture, one with a depressed orbital floor fracture, and one with a severely comminuted orbital floor. In two patients, coronal computed tomography showed inferior rectus muscle entrapment, which was confirmed at the time of surgery. In each patient, some bone fragments could be seen more discreetly on coronal computed tomography than on conventional polytomes. Coronal computed tomography may be used to help confirm extraocular muscle entrapment in patients with orbital floor fractures. Coronal computed tomography can also be used to examine patients with possible intraorbital foreign bodies, unexplained reduction of vision, or severely displaced bone fragments.

Adult↗

PubMed1978

Computed tomography of the orbit with special emphasis on coronal sections: Part I. Normal anatomy.

Computed tomography (CT) of the orbit is capable of demonstrating soft tissue structures not visualized yet by any other radiological modality. The possibility of obtaining direct coronal slices has added a new dimension to the study. Direct enlargement viewing on the display console reveals many anatomical details. For better evaluation of pathological findings, an accurate anatomical knowledge is required. The purpose of this study is to report on the normal anatomy of the orbital soft tissues made visible by CT, with emphasis on the coronal views.

Adipose Tissue↗

PubMed1978

Computed tomography of the orbit with special emphasis on coronal sections: Part II. Pathological anatomy.

Visualization of orbital soft tissue structures by computed tomography in direct coronal and axial studies is extremely useful in diagnosis. Direct enlargement viewing of scans has disclosed minute anatomical details. This study reviews some of our experiences in the investigation of a variety of lesions within the orbit and attempts, in particular, to illustrate the value of direct coronal studies.

Adult↗

PubMed1978

Computed tomography of the paranasal sinuses and face: part I. Normal anatomy.

With the ability to image both bone and soft tissue structures, computed tomography (CT) is capable of visualizing many normal anatomical structures of the paranasal sinuses and face not seen with other radiological techniques. The superficial and deep fat planes, all of the muscles of mastication, and many of the facial muscles are readily identified. The extraocular muscles, optic nerves, and globes are clearly seen. The purpose of this report is to review the normal anatomy of the paranasal sinuses and face imaged by CT in both the transverse and coronal planes.

Face↗

PubMed1978

Computed tomography of the paranasal sinuses and face: part II. Pathological anatomy.

Computed tomography (CT) has added an important new dimension to the radiological evaluation of diseases of the paranasal sinuses and face. Using transverse and coronal scans, accurate assessment of the character and extent of mass lesions in this region can be achieved. Erosion of thin bony lamine and involvement of soft tissue structures of the face can be seen. Most important, CT is capable of precisely defining the extension of lesions into the pterygopalatine fossa, orbit, and cranial cavity, information that is essential for therapeutic planning.

Adult↗

PubMed1978

Computed tomographic evaluation of traumatic spinal injuries.

A full radiological evaluation of patients who sustained traumatic injuries to the spine may be difficult to obtain due to the danger associated with manipulation. Computed tomography offers a new modality for simple and accurate evaluation; valuable information may be gained without the use of invasive methods.

Humans↗

PubMed1977

Computed tomographic examination of heavy marijuana smokers.

Computed tomographic scans were obtained from 19 men with long histories of heavy marijuana smoking and who were also observed to smoke large amounts of marijuana under research ward conditions. The ventricular system and subarachnoid spaces were normal in size and showed no indication of atrophic change.

Adult↗

PubMed1977

Computed tomography of the skull and facial structures: preliminary evaluation of direct coronal sections.

Skull and facial structures may be evaluated on computed tomography (CT), as well as the brain. A valuable new dimension to the study has been added with the feasibility of obtaining direct coronal sections using a wide gantry aperture. The patho-anatomical details of bone and soft tissues including the orbit and paranasal sinuses are well demonstrated. Direct viewing on a display console of an enlarged quadrant of the scan is of prime importance in diagnosing fine changes involving the thin facial bones.

Humans↗