MR Imaging Findings of Orbitofacial Infarction Secondary to Rhinoorbital Mucormycosis: A Case Report

Rhino-orbital mucormycosis is the most frequently fatal fungal infection commonly occurring in patients with poorly controlled diabetes mellitus and and those who are immunocompromised, and requires prompt treatment. We describe a case of rhino-or-bital mucormycosis with orbital cellulitis and paranasal sinusitis, as seen on initial MR images, which on follow-up images had evol ved to orbitofacial infarction. MR imaging was useful for the demonstration of orbitofacial infarction, seen as areas of lack of enhancement and thus suggesting vascular invo l vement by mucor hyphae.

CT Findings of Tracheal Mucormycosis: A Case Report

Pulmonary mucormycosis is a opportunistic mycosis, typically occurring in immunocompromised or diabetic patients. It is characterized as an infection of the pulmonary parenchyma and larger bronchi, and involves extensive vascular thrombosis and tissue necrosis. A variety of CT findings have been reported, but tracheal involvement is extremely rare. We report the case of a patient with tracheal mucormycosis placing particular emphasis on the CT findings.

Diagnosis of Meniscal Tear of the Knee Using Proton-weighted Fast Spin-Echo MR Imaging: Can be an Alternative to Conventional Spin-Echo Imaging?

PURPOSE: The purpose of this study was to evaluate the sensitivity and specificity of proton-weighted fast spin-echo MR imaging in diagnosing the meniscal tear of knee as an reasonable substitute for conventional spin-echo imaging. MATERIALS AND METHODS: 102 consecutive patients, proved by surgery, were participated in this study. All of them were suspected internal derangement of knee, examined by fast spin-echo MR imaging including sagittal and coronal images on a 1.5T MR imager and underwent arthroscopic or open surgery of knee joint within 2 months. These images were reviewed retrospectively by three radiologists. The sensitivity and specificity of meniscal tear were calculated. RESULTS: The sensitivity and specificity of meniscal tear reviewed by proton-weighted fast spin-echo MR imaging were 94%, 93% in medial meniscus and 92%, 88% in lateral meniscus. CONCLUSION: The sensitivity and specificity of meniscal tear using proton weighted fast-spin echo MR images were as high as those using conventional spin-echo MR imaging in diagnosing meniscal tear of the knee.

Diffusion-weighted Imaging of Cerebral Ischemic Infarcts: Comparison with T2-weighted Imaging in Signal Intensity

PURPOSE: To investigate whether ischemic infarct can be staged by evaluating signal intensities on diffusionweighted (DWI) and turbo spin echo T2-weighted images(T2WI). MATERIALS AND METHODS: DWI and T2WI of 27 patientswith ischemic infarct were retrospectively evaluated. Infarcts were divided into five stages depending on time ofonset : hyperacute within 12 hours, acute between 12 hours and 3 days, subacute between 3 and 10 days, earlychronic between 10 and 30 days, and late chronic after 30 days. Signal intensities of these lesions compared withnormal brain on DWI and T2WI were visually evaluated and divided into six patterns. Pattern 1 included high signalon DWI and iso-signal on T2WI, pattern 2 showed high signal on both DWI and T2WI with higher contrast on DWI,pattern 3 showed the same high signal on both images; pattern 4 revealed high signal on both images with highercontrast on T2WI, pattern 5 showed iso-signal on DWI and high signal on T2WI, and pattern 6 revealed low signal onDWI and high signal on T2WI. These five clinical stages and six MRI patterns were correlated in each patient. RESULTS: Six cases were hyperacute, six were acute, eight were subacute, three were early chronic, and four werelate chronic. At the hyperacute stage, five cases showed pattern 1 (83%) and one case, pattern 2. At the acutestage, all six cases showed pattern 2. At the subacute subcute stage, seven cases showed pattern 2(87.5%) and onecase pattern 4. At the early chronic stage, two cases showed pattern 2(66.7%) and one case, pattern 5. At the latechronic stage, all cases showed pattern 6. CONCLUSION: DWI is useful for the detection of early ischemic infarct,and stages of ischemic infarcts can be estimated by evaluating signal intensities on DWI and T2WI.

Renal Excretion of Gastrografin after Oral Administration: Clinical Significance in Gastric Resection Patients

PURPOSE: To evaluate the clinical significance of renal excretion of oral Gastrografin in gastric resectionpatients. MATERIAL AND METHOD: Seven days affter gastric resection, eight normal volunteers and 30 patientsunderwent abdominal and CT scanning before and 1-1.5 his after oral administiration of Gastrografin. Theattenuation coefficients of the bladder were measured and the maximal attenuation difference between pre-andpost-gastrografin administration was calculated. RESULTS: In the control group, there was no abnormal renalexcretion of oral Gastrografin, though in 83 % of patients(25 of 30), this was demonstrated as focal increase inthe density (> or = 20 HU) of the bladder and/or collecting system, or ureteral opacification. Mean maximal densitydifference was 84.4+/-82.9HU in the patient group (n=24), with renal excretion of enteral Gastrografin and,3.5+/-4.4 HU in the control group (n=7), with statistical significance (Student's t-test, p<0.01). No patientshowed either radiological or clinical evidence of direct leakage from the suture site. Patients who underwenttotal gastrectomy showed a higher maximal density difference than those in whom gastrectomy was subtotal. CONCLUSION: Unless direct leakage is visvalized on fluoroscopy or spot films, renal excretion of oralGastrografin should not be regarded as a sign of anastomotic leakage. Situations other than leakage, e. g.increased mucosal permeability or absorption, or increased bowel transit time in postoperative duration, should beconsidered as possible causes.