PubMed Health⌕ Search

Biomedical subjects

G E Simmons

Publications and source records attributed to G E Simmons.

10 recordsLinked to original sources
PubMed1997

Detection of interstitial lung abnormalities on picture archive and communication system video monitors.

The purpose of this study was to compare the detection of interstitial lung abnormalities on video display workstation monitors between radiologists experienced with video image interpretation and radiologists who lack this experience. Twenty-four patients with interstitial lung abnormalities documented by high-resolution computed tomography (HRCT) and lung biopsy, and 26 control patients with no history of pulmonary disease or a normal HRCT and normal chest radiographs were studied. Images were acquired using storage phosphor digital radiography and displayed on 1,640 x 2,048 pixel resolution video monitors. Five board-certified radiologists evaluated the images in a blinded and randomized manner by using a six-point presence of abnormality grading scale. Three radiologists were from 1 to 4 years out of residency and considered to be experienced workstation monitor readers with between 1 to 3 years of video monitor image interpretation. For the inexperienced readers, one radiologist had no prior experience with reading images from a video monitor and was direct out of residency, and the other radiologist had less than 4 months of intermittent exposure and was 1 year out of residency. Sensitivity and specificity were determined for individual readers. Positive predictive values, negative predictive values, accuracy, and receiver-operating curves were also generated. A comparison was made between experienced and inexperienced readers. For readers experienced with video monitor image interpretation, the sensitivity ranged from 87.5% to 92%, specificity from 69% to 92%, positive predictive value (PPV) from 73% to 87.5%, negative predictive value (NPV) from 87% to 90%, and accuracy from 80% to 88%. For inexperienced readers, these values were sensitivity 58%, specificity 50% to 65%, PPV 52% to 61%, NPV 56.5% to 63%, and accuracy 54% to 62%. Comparing image interpretation between experienced and inexperienced readers, there were statistically significant differences for sensitivity (P < .01), specificity (P < .01), PPV (P < .05), NPV (P < .05), accuracy (P < .05), and area under the receiver operator curve (Az) (P < .01). Within the respective experienced and inexperienced groups, no statistical significant differences were present. Our results show that digitally acquired chest radiographs displayed on high-resolution workstation monitors are adequate for the detection of interstitial lung abnormalities when the images are interpreted by radiologists experienced with video image interpretation. Radiologists inexperienced with video monitor image interpretation, however, cannot reliably interpret images for the detection of interstitial lung abnormalities.

Adult↗
PubMed1997

Investigation of the validity and reliability of four objective techniques for measuring forward shoulder posture.

Clinicians often rely on visual inspection and descriptive terms to documents a patient's forward shoulder posture. The purpose of this study was to assess the validity and intrarater reliability of four objective techniques to measure forward shoulder posture. Subjects were 25 males and 24 females. Subjects had a lateral cervical spine radiograph taken, from which the horizontal distance from the C7 spinous process to the anterior tip of the left anterior acromion process was measured. Subjects then proceeded twice through a random order of four measurements: the Baylor square, the double square, the Sahrmann technique, and scapular position. These results were then used to determine the intrarater reliability of each technique. Multiple regression analyses were performed on each measure's mean scores to determine both the correlation with and the predictive value for the radiographic measurement. The intraclass correlation coefficients for intrarater reliability ranged from .89 to .91. The correlation coefficients ranged from -.33 to .77, and the coefficients of determination ranged from .10 to .59 (N = 49). The researchers demonstrated clinical reliability for each technique; however, validity compared with the radiographic measurement could not be established. These techniques may have clinical value in objectively measuring change in a patient's shoulder posture as a result of a treatment program. Before any of these measures could be universally recommended in clinical practice, future research is necessary to establish interrater reliability and assess each technique's ability to detect postural changes over time.

Adult↗
PubMed1996

MR diagnosis of bone contusions of the knee: comparison of coronal T2-weighted fast spin-echo with fat saturation and fast spin-echo STIR images with conventional STIR images.

OBJECTIVES: Bone contusions consist of posttraumatic marrow change resulting from a combination of hemorrhage, edema, and microtrabecular injury and are depicted on MR images as geographic, nonlinear areas of abnormally increased T2 marrow signal intensity. Detection of bone contusions is important, not only in that they are frequently a sign of more serious associated injury, but in that isolated contusions may account for clinical symptoms and thereby obviate further workup. We evaluated two promising rapid imaging sequences, T2-weighted fast spin-echo with fat saturation and fast spin-echo short inversion time (T1) inversion recovery (STIR) and compared their efficacy to that of conventional STIR for the diagnosis of bone contusions in knees. SUBJECTS AND METHODS: Fifty-one consecutive military, retired military, and military-dependent patients were prospectively entered. Imaging consisted of three experimental sequences: coronal T2-weighted fast spin-echo with spectroscopic fat saturation, fast spin-echo STIR, and STIR, as well as conventional T1, proton density, and T2. Each examination was interpreted by three radiologists, for a total of 153 interpretations. Each interpretation consisted of the conventional sequences plus one of the three experimental sequences, blinded to the other two, specifically addressing menisci, ligaments, bones, and soft tissues. A positive test result was defined as a diagnosis of bone contusion on any one of the three independent interpretations of a given examination. Our gold standard was the consensus opinion of all three radiologists in a retrospective, unblinded evaluation of all imaging sequences. Sensitivity and specificity of fast spin-echo with fat saturation and fast spin-echo STIR were then calculated and compared with STIR. RESULTS: Sensitivity and specificity for bone contusion diagnosis in the three experimental sequences were as follows: fast spin-echo with fat saturation, 91% sensitivity and 86% specificity; fast spin-echo STIR, 96% sensitivity and 96% specificity; and conventional STIR, 83% sensitivity and 93% specificity. Our results showed no statistically significant difference between either of the fast spin-echo sequences and conventional STIR (p > .05). CONCLUSION: Because of their comparable accuracy and short imaging time characteristics, coronal fast spin-echo with fat saturation and fast spin-echo STIR sequences are superior to conventional STIR sequences for the diagnosis of bone contusions in knees.

Adolescent↗
PubMed1992

MR imaging of the pituitary stalk: size, shape, and enhancement pattern.

The size, shape, signal intensity, and enhancement pattern of the normal pituitary stalk were determined retrospectively by review of MR images of 58 patients. The pituitary stalk was measured at the level of the optic chiasm and at its insertion on the pituitary gland. The contour of the stalk was smoothly tapering, measuring 3.25 +/- 0.56 mm in transverse diameter at the optic chiasm and 1.91 +/- 0.40 mm at its pituitary insertion. The signal intensity of the pituitary stalk on unenhanced T1-weighted images was less than that of the neurohypophysis in all cases and less than that of the optic chiasm in 84% of the cases. After the administration of contrast material, enhancement of the pituitary stalk occurred in all cases. A central area of nonenhancement in an otherwise uniformly enhancing stalk was variably present, depending on the size of the infundibular recess. Our study defines the size, contour, and MR signal characteristics of the normal pituitary stalk. These criteria can be used to distinguish the normal from the abnormal stalk.

Adult↗
PubMed1989

Subcutaneous myospherulosis.

Myospherulosis is an uncommon subcutaneous disorder believed initially to be caused by an endosporulating fungus. Recently investigators have disproved an infectious cause and have shown that the disease represents an alteration in red blood cells, usually produced by petrolatum or lanolin, with an accompanying foreign-body-type response. We report the case of a 57-year-old woman who had received a penicillin injection approximately 40 years before she developed a cystic mass in the right buttock. Examination of the mass revealed the classic histologic findings of this disease.

Buttocks↗
PubMed1987

Adenomyoma of the papilla of Vater.

An adenomyoma of the papilla of Vater that caused biliary obstruction resulted in an extensive surgical resection because of the clinical and roentgenographic suspicion of carcinoma. Benign neoplasms of the papilla and extrahepatic bile ducts are exceedingly rare, but their recognition is of clinical importance. Histologically, the adenomyoma, characterized by lobules of ducts and ductules with interlacing bundles of smooth muscle, was similar to the adenoleiomyomatous hamartoma of the intestines and to lesions of the gallbladder or extrahepatic ducts known as adenomyomas or adenomyomatous hyperplasia. The presumed rapid recent growth of the present lesion, as roentgenographically documented by the recent onset of dilatation of the common bile duct in an elderly woman, as well as the lack of gallstones or inflammatory disease of the biliary tract, might support the contention that the present lesion was neoplastic. On the other hand, the possibility that the lesion represents a hamartoma or diverticulosis of the saccules of Beale cannot be excluded.

Aged↗