Benign and malignant sinonasal lesions with intracranial extension: differentiation with MR imaging

Most sinonasal lesions that extend into the anterior cranial fossa are malignant tumors. However, benign inflammatory polypoid disease can also rarely be manifested in this manner. Fourteen surgically proved cases of such benign and malignant disease were studied with magnetic resonance (MR) imaging. The appearances of the benign and the malignant lesions were quite different and allowed the seven chronic polypoid lesions to be distinguished from the tumors. The benign lesions had nonhomogeneous appearances on MR images due primarily to varying degrees of free-water resorption and protein concentration. The tumors had primarily homogeneous low-to-intermediate signal intensities due to their highly cellular composition.     

Intracranial circulation: preliminary clinical results with three- dimensional (volume) MR angiography

The authors assessed the clinical utility of a magnetic resonance angiography technique in the evaluation of intracranial circulation. Eighteen patients with a low likelihood of cerebrovascular disease (control group) and 40 patients with suspected cerebrovascular disease were imaged with a FISP (fast imaging with steady precession) sequence (repetition time of 50 msec, echo time of 15 msec, velocity compensation in the read and section-select directions with acceleration compensation in the read direction, 15 degrees anisotropic volume, and a 1.25-mm partition thickness). Ninety-four percent of images in the control group and 72% of images in the group with cerebrovascular disease were considered useful for diagnosis. This technique can provide accurate images of intracranial circulation and can be performed in conjunction with two-dimensional spin-echo or gradient-echo imaging. It was most useful in the evaluation of patent intracranial aneurysms, vessel displacement, and large-vessel occlusive disease. Disadvantages included limited field of view, persistent signal voids, limited spatial resolution, and inadequate depiction of lesions with slow flow.     

Repeated administration of recombinant human insulin-like growth factor-I in patients after gastric surgery. Effect on metabolic and hormonal patterns.

OBJECTIVE: The primary objective of this investigation was to evaluate the anticatabolic effects of repeated subcutaneous administration of recombinant human insulin-like growth factor-I (rhlGF-I) in patients after gastric surgery. SUMMARY BACKGROUND DATA: The anabolic and protein-sparing effects of growth hormone are primarily mediated by IGF-I. Malnutrition and catabolic states result in increasing blood levels of growth hormone and decreasing levels of IGF-I. Experimental data showed that exogenous IGF-I could attenuate or reverse catabolism. METHODS: After giving their written informed consent, 38 male and female patients undergoing gastrectomy (age 40-75 years, body mass index 17-30 kg/m2) were treated with 80 micrograms/kg body weight rhlGF-I or placebo in a prospective, randomized, double-blind study for 5 consecutive days. Patients received a standardized total parenteral nutritional regimen with 3 g/kg body weight glucose and 0.1 g/kg body weight nitrogen. Nitrogen balance and 3-methylhistidine excretion were measured daily. Hormone profiles (IGF-I, IGFBP1, IGFBP3, cortisol, insulin, glucagon, triiodothyronine [T3], levothyroxine [T4], and thyroxine-binding globulin) were taken.     

Common tumors of the parapharyngeal space: refined imaging diagnosis

Computed tomographic (CT) scans and magnetic resonance (MR) images in 103 patients with either a deep-lobe parotid tumor extending into the parapharyngeal space, a minor salivary gland tumor, a neuroma, or a paraganglioma were reviewed. The parotid or extraparotid nature of these masses was established by identifying a fat plane between the mass and the parotid gland. This was more reliably accomplished with MR imaging than with CT. Although dynamic CT allowed identification of the glomus tumors, MR imaging also permitted diagnosis of these lesions. The inherent CT and MR imaging characteristics of most of the neuromas and minor salivary gland tumors were indistinguishable. However, the neuromas tended to displace the internal carotid artery anteriorly, whereas the salivary lesions displaced this vessel posteriorly. This artery was better identified on MR images than on CT scans. Thus, these lesions, which are the four most common primary parapharyngeal space tumors, can be distinguished on MR images by evaluating not only their inherent signal characteristics but also the surrounding fat planes and any displacement of the internal carotid artery.     

Dynamics stress echocardiography for evaluating anti-ischemic drug profiles in post-MI patients

Exercise ECG is an established method of evaluating the anti-ischemic properties of drugs. However, there are considerable methodologic limitations to this procedure and its use is restricted to patients with exercise-provoked ECG alterations which can be interpreted as ischemia. The principal, earlier onset of wall motion abnormalities according to the ischemic cascade can be detected by stress echocardiography and might be utilized as a pharmacological stress testing modality. Sixteen consecutive patients (15 men, one woman; 53 ± 9 years old) with angiographically proven coronary artery disease (8 with one-, 5 with two-, and 3 with three-vessel disease) and exercise-induced wall motion abnormalities were examined by dynamic stress echocardiography (50 watt followed by 20-watt increases/min). Anti-ischemic drugs were withdrawn prior to and on day 1; on the following day 2, 0.2 µg/kg/min nisoldipine was infused intravenously during the test after a 3 µg/kg bolus was given. At maximum comparable workload 15/16 patients showed an improved wall motion score on treatment (day 1: 22.9 ± 4.9 vs day 2: 20.0 ± 3.9; normal score: 12; one-sided binomial test: p = 0.0003). Eight of 16 patients demonstrated ST-segment deviations on day 1 and day 2. The double product did not differ at any workload stage until the maximum of 130 watt (day 1: 14101 ± 3140 vs day 2: 13365 ± 2865; n.s.). Dynamic stress echocardiography seems to be a valuable tool in pharmacologic stress testing and in terms of accuracy is supposed to be superior to conventional exercise ECG. Nisoldipine reduces exercise-induced wall motion abnormalities in patients with and without exercise-induced ECG alterations. The data result from a controlled pilot study, and further studies are required to confirm these promising methodological and therapeutic findings.