OBJECTIVE: To evaluate the olfactory fossae depth according to the Keros' classification and determine the incidence and degree of asymmetry in the height and contour of the ethmoid roof. MATERIALS AND METHODS: Retrospective analysis of 200 coronal computed tomography studies of paranasal sinuses performed in the period between August and December, 2006. RESULTS: According to the Keros' classification, olfactory fossae type II was most frequently found in 73.3% of cases followed by type I in 26.3% and type III in 0.5% of cases. Asymmetry in the ethmoid roof height was found in 12% of cases (24 computed tomography studies), and contour asymmetry was found in 48.5% (97 computed tomography studies), with flattening of the ethmoid roof on one of the sides. CONCLUSION: As regards the olfactory fossae depth, the Keros' type II was most frequently found. In most of cases, the ethmoid roof asymmetry was related to angulation of the lateral lamella of the cribriform plate.

Keywords: Anatomy, Nose, Nasal cavity, Computed tomography, Fovea ethmoidalis, Olfactory fossa

OBJECTIVE: To evaluate the results of hepatocellular carcinoma arterial chemoembolization in cirrhotic patients awaiting liver transplantation. MATERIALS AND METHODS: Twenty-three cirrhotic patients with hepatocellular carcinoma awaiting liver transplantation were submitted to multiple sessions of chemoembolization using mitomycin C and lipiodol. A prospective evaluation of the following factors was performed: a) serum levels of alpha-fetoprotein; b) tumor size; c) maintenance of the viability criteria for hepatic transplantation; d) degree of liver dysfunction. RESULTS: The mean serum levels of alpha-fetoprotein were reduced by 43% during the first 13 months. The mean tumor size, as measured by the long axis, after a mean follow-up period of 13.5 months was 3.2 cm, which is considered stable for the period according to the World Health Organization criteria. The mean survival rate was 14 months. CONCLUSION: In this trial, pre-transplantation use of chemoembolization in combination with an adequately chosen therapy showed few complications and contra-indications as well as a considerable anti-tumor efficacy. Despite the fact that the adopted therapy increased survival rates in comparison to historical evolution data in hepatocellular carcinoma, this increase had not the same dimension if the median waiting time for transplantation is taken into consideration. Therefore, other strategies need to be associated to either make survival rate longer or to reduce transplantation waiting time.

Keywords: Hepatocellular carcinoma, Chemoembolization, Lipiodol

OBJECTIVE: To quantify bone formation within autogenous bone grafts and autogenous bone grafts in combination with platelet-rich plasma obtained either from aphaeresis or centrifugation using computed tomography. MATERIALS AND METHODS: This prospective, double-blind study was conducted in 34 male and female adult patients (mean age of 28 years and 8 months), with either unilateral or bilateral pneumatization of the maxillary sinuses, requiring bone graft for dental implant. All patients were submitted to computed tomography examinations prior and six months after sinus lift surgery. Fifty-three maxillary sinuses were operated and divided into three distinct groups: autogenous bone graft, autogenous bone graft in combination with platelet-rich plasma obtained by centrifugation, and autogenous bone graft in combination with platelet-rich plasma obtained by aphaeresis. RESULTS: Computed tomography demonstrated bone growth in height and width between the initial and the follow-up computed tomography scans in all three groups. However, no statistical difference was found either for bone height or width. CONCLUSION: Clinical evidence demonstrates the effectiveness of autogenous bone grafts, particularly when used in combination with bone growth factors such as platelet-rich plasma, which allow prosthetic and functional restoration of maxillofacial structures through fixation of dental implants.

Keywords: Computed tomography, Maxillary sinus, Bone graft, Platelets, Aphaeresis

The most important diagnostic sign of ureterolithiasis is the direct visualization of the stone within the ureter. However, in some patients with ureterolithiasis stone visualization may be impaired due to stone small size or low attenuation, respiratory artifacts between data acquisitions, low amount of retroperitoneal fat or recent elimination of the stone. In this context, we describe many secondary computed tomography signs of ureteral obstruction that may useful in the diagnosis of inconclusive cases, and also quantify the degree of urinary obstruction.

Keywords: Computed tomography, Acute flank pain, Ureteral stone

OBJECTIVE: To investigate the advantages of using modified signal intensity measurements on chemical shift imaging alone or in conjunction with proton magnetic resonance spectroscopy in the differential diagnosis of adrenal adenomas. MATERIALS AND METHODS: This was a prospective study involving 97 patients with adrenal nodules or masses. The signal intensity index (SII) was calculated as [(signal intensity on the in-phase image − signal intensity on the out-of-phase image) / (signal intensity on the in-phase image)] × 100%. We determined the averages of the minimum, mean, and maximum signal intensity values measured on three consecutive images. When that was not possible (for smaller lesions), we used one or two images. We employed a region of interest that covered one half to two thirds of the mass. All indices were compared with metabolite ratios derived from spectroscopy: lactate/creatine; glutamine-glutamate/creatine; choline/creatine; choline/lipid; 4.0–4.3 ppm/Cr; and lipid/creatine. RESULTS: Of the 97 patients evaluated, 69 were diagnosed with adenomas and 28 were diagnosed with nonadenomas. All SII measurements and spectroscopy-derived metabolite ratios were significant to the differentiation between adenomas and nonadenomas, except for the lipid/creatine and choline/lipid ratios. In 37.8% of the cases, it was not possible to perform spectroscopy. When it was possible, the lactate/creatine ratio was found to have higher accuracy than did the SII. CONCLUSION: Determining the SII and metabolite ratios increased the accuracy of the differential diagnosis of adrenal adenomas.

Keywords: Adrenal glands; Adrenal gland neoplasms; Adenoma/diagnostic imaging; Magnetic resonance imaging/methods; Proton magnetic resonance spectroscopy/methods.