Morphometric analysis of the odontoid process: using computed tomography--in the Greek population.

AIM: A morphometric analysis of the odontoid process of the A2 vertebra, in the Greek population, was conducted using CT scan. We aimed to determine the feasibility to use one or two screws when treating fractures of this anatomic element. PATIENTS AND METHODS: One hundred and fifteen patients (57 men) of a mean age of 48 years (16-95 years) underwent a cervical spine CT scan examination. The anterior-posterior and transverse diameters of the odontoid process were measured from the base, at 1-mm interval upward on axial CT images. The length from the tip of the odontoid process to the anterior-inferior angle of the body of the axis was calculated. Data concerning the height and weight of the examined patients were collected. RESULTS: The mean transverse and anterior-posterior distances were found to be 11.46 and 10.45 mm, respectively, for the upper end of the odontoid process. At the neck level of the odontoid process, the equivalent mean values were 11.12 and 8.73 mm, respectively, while at the base, these distances were found to be 13.84 and 12.3 mm, respectively. The mean distance from the tip of the odontoid to its base was 17.25 and 17.28 mm, respectively, while the mean distance from the tip of the dens to the anterior-inferior corner of the axis' body was 39.2 mm. Men showed greater values than women. CONCLUSIONS: In this study, it was shown that in the Greek population there is enough room for one 4.5-mm or one 3.5-mm cannulated screw to be used. The application of two 3.5-mm screws is feasible in 58.6 % of the male and 26.3 % of the female population. This confirms that the knowledge of the true dimensions of the odontoid process is of paramount importance before the proper management of fractured dens using the anterior screw technique.

Groove pancreatitis: a diagnostic challenge.

Groove pancreatitis is a distinct form of chronic pancreatitis characterized by inflammation and fibrous tissue formation, affecting the groove area between the head of the pancreas, the duodenum and the common bile duct. It is manifested on imaging by a sheet-like mass in the groove area near the minor papilla. Thickening of the duodenal wall and cystic transformation in the duodenal wall also represent common imaging features. Pathogenesis is still unclear, and clinical presentation is not specific. Endoscopic ultrasonography (EUS), computed tomography (CT) and magnetic resonance imaging (MRI) demonstrate imaging findings consistent with the disease in typical cases, but specific diagnosis is challenging in a number of patients where biopsy is required. The disease may mimic pancreatic, common bile duct or duodenal wall cancer that requires prompt and excessive surgical intervention, as opposed to groove pancreatitis where initial conservative treatment is suggested. The clinical, histopathological and radiological features on cross-sectional imaging of this entity are discussed in this review, and differential diagnostic clues are given.

The acute effect of Orlistat on dietary glycotoxins in diabetics and healthy women.

AIM: Advanced glycation end products (AGEs) formation is implicated in diabetic complications. Exogenous AGEs, namely glycotoxins, are present in certain foods and are absorbed from the gastrointestinal tract. Experimental data suggest that lifestyle interventions reducing their content in diet have beneficial effect. METHODS: Fourteen healthy (age: 42.14 +/- 12.38 years; body mass index [BMI]: 27.85 +/- 7.06 kg/m2) and ten women with type 2 diabetes (T2DM) (age: 48.70 +/- 9.31 years; BMI: 32.55 +/- 7.14 kg/m2) were enrolled in the study. A meal rich in AGEs was provided in a two-day protocol and on day 2, 240 mg of Orlistat were administered post-meal. RESULTS: On day 1, serum AGEs levels showed a rise at 3 hours post-meal compared to baseline values in both groups (controls: 12.2%; P<0.001), T2DM: 2.6%; P=0.013), but at 5 hours post-meal only in the controls (control: 12.2%; P<0.001); T2DM: 1.9%; P=0.075). On day 2 at 3 hours post-meal control values showed a rise of 3.1% (P=0.003); T2DM of 1.9% (P=0.013); at 5 hours post-meal rise for controls was 4.6% (P=0.012); and for T2DM was 1.8% (P=0.009). The corresponding rise was significantly lower on day 2 only in controls at 3 and 5 hours post-meal (P=0.003; P=0.05, respectively). CONCLUSIONS: Orlistat reduced the absorption of glycotoxins acutely and improved the metabolic profile in the control group, without an apparent beneficial effect in the diabetic group. The clinical significance of this observation should be further investigated in normal population, while in diabetics long-term studies may be required to demonstrate possible clinically significant effects.

Patient skin dose assessment during CT-guided interventional procedures.

The purpose of this study was to investigate patient skin doses in the most frequent computed tomography-guided interventional radiology procedures. The study includes 14 abdominal biopsies and 15 radiofrequency (RF) ablations. Patient skin dose was assessed by slow verification films. The technical factors recorded were: tube kilovoltage (kVp), tube load (mAs), slice thickness and the total number of slices (S). The median value of maximum entrance skin dose (ESD(M)) in biopsy was 108 mGy (9.5-282 mGy). S had a range of 4-152 with a median of 44 slices. Significant correlation was found between S and dose (r = 0.80). Median ESD(M) in RF ablation was 238 mGy (104-500 mGy). S had a range of 108-175 with a median of 155 slices. No significant correlation was found between S and dose. The large range of results show that a more extensive investigation should be performed. In summary, diagnostic procedures such as biopsy present patient skin doses that are relatively low. On the other hand, patient skin dose in RF ablation can be high and can reach values higher than the value that a slow verification film is capable of measuring (1.2 Gy). For these procedures, an alternative method should be investigated.

CT appearance of pulmonary hydatid disease.

The principal features of computed tomography in hydatid disease of the lungs were reviewed in ten patients with surgically verified hydatid disease of the lungs. On the basis of localization and multiplicity, hydatid cysts of the lungs can be classified in three distinct categories: single unilateral unilocular cysts with or without daughter cysts, unilateral multiple cysts with or without daughter cysts, and bilateral multiple cysts. Cystobronchial communication may lead to cavitary lesions, while infection of the cyst may alter the attenuation values and produce a solid appearance. On the basis of density and clinical symptoms, hydatid cysts of the lungs can be classified as simple cysts, complicated cysts, and ruptured cysts, including cystobronchial communication.

Pelvic lymphocysts after radical hysterectomy and lymphadenectomy.

Five cases (5.5%) of lymphocysts were diagnosed and treated, among 80 type III modified radical hysterectomies performed for cervical cancer St. Ia2-IIa, in the last 6 years. Identification was initially made by palpation and confirmed by CT or US, in 4/5 cases in the first 2 postoperative months. Pelvic pain, fever and pressure symptoms were the most common clinical findings. A conservative approach was successful in 4/5 cases. Spontaneous regression was observed in one, while needle aspiration under radiologic guidance with (1/3) or without (2/3) tube insertion was applied in the rest. Conservative treatment failed in the last case presenting with a 12 cm cyst. An intestinal fistula developed, necessitating partial resection of the ileus and marsipulization. The complicated course of this patient's disease may indicate that a more aggressive treatment is warranted for large persisting cysts located in the irradiated field.

MRI features in a malignant glomus jugulare tumour.

Magnetic resonance imaging (MRI) features in a case of malignant glomus jugulare tumour are reported. Chemodectomas are benign in 95 per cent of cases and malignant in five per cent. Only one case report of CT findings in this unusual CP angle tumour with pulmonary metastases has been cited in the literature. It is concluded that MRI can provide useful information about the nature of chemodectomas although it cannot distinguish between benign and malignant tumours, except when regional lymph nodes are involved or when distant metastases exist.

Radiation dose in repeated CT guided radiofrequency ablations.

OBJECTIVE: To calculate the cumulative effective and skin doses in patients that underwent repeated CT guided radiofrequency ablations (RFA). MATERIALS AND METHODS: From all patients that had undergone RFA during a five years period those which had three or more RFAs were selected. Using the CT images DICOM data, the dose length product (DLP), effective dose (E), skin dose profiles as well as the peak skin dose (PSD) were calculated, using appropriate methods and software developed for this purpose. For each patient, cumulative DLP and E were also calculated from the sum of the respective figures of each individual procedure. To calculate PSD, the skin dose profiles of each procedure were overlaid on the same Z-axis scale using anatomical landmarks for reference and the skin doses to each point were summed up. RESULTS: Five patients were studied; four had undergone 3 RFAs and one 10 RFAs. Cumulative DLP, E and PSD ranges were 5.6-22.3 Gy cm, 0.08-0.36 Sv and 0.8-3.4 Gy, respectively. Median E and PSD values per RFA were 35 mSv and 0.4 Gy, respectively. For comparison purposes it must be noted that in this CT department a routine abdomen-pelvis scan results to an E of about 10 mSv. CONCLUSIONS: Patients that undergo repeated RFAs are exposed to considerably high radiation exposure levels. When these patients are in the final stage of malignant diseases, stochastic effects may not be of major concern. However, optimization of the exposure factors and monitoring of these patients to avoid skin injuries are required.

Solid pseudopapillary tumor of the pancreas: an enigmatic tumor.

Solid pseudopapillary tumor of the pancreas is a rare pancreatic tumor that predominantly occurs in young non-Caucasian women. Although most tumors show benign behavior, malignant degeneration may occur. A case of solid pseudopapillary pancreatic tumor in a Caucasian woman is presented that was investigated by endoscopic ultrasonography (EUS), computed tomography, magnetic resonance imaging and EUS-guided fine needle aspiration. The patient underwent surgery and radiological findings are correlated with histopathology. The preoperative diagnosis of solid pseudopapillary tumor of the pancreas is challenging, frequently leading to imaging by multiple different modalities.

Virtual bronchoscopy versus thin section computed tomography in evaluation of moderate and low grade stenoses: receiver operating characteristic curve analysis.

PURPOSE: To evaluate the impact of virtual bronchoscopy, under proper threshold settings, on observer level of confidence in the assessment of bronchial abnormalities producing stenoses < or = 75% compared to interpretation of thin section computed tomography (CT) images. MATERIAL AND METHODS: Sixty-five patients with fiberoptic bronchoscopy positive for tracheobronchial abnormalities were evaluated in a blinded observer study using a commercially available virtual endoscopy software package. The findings of virtual endoscopy were compared with those of fiberoptic bronchoscopy using receiver operating characteristic curves (ROCs) and other statistical tools. RESULTS: A total of 102 lesions were identified by fiberoptic bronchoscopy, with 44 of these producing bronchial stenoses < or = 75%. Concerning the latter lesions, for virtual bronchoscopy the areas under the ROCs were 0.93 and 0.96 for the two observers, respectively, while for thin section CT the corresponding values were 0.86 and 0.88; the differences observed were statistically significant. Contrary to thin section CT, virtual bronchoscopy did not show statistically significant differences from fiberoptic bronchoscopy regarding estimation of degree of stenosis. CONCLUSION: Virtual bronchoscopy under proper threshold settings has a statistically significant impact on observer performance where moderate and low-grade bronchial stenoses are concerned and gives an estimate of the degree of stenosis more precisely than thin section CT.