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.

The effect of laparoscopic sleeve gastrectomy on the antireflux mechanism: can it be minimized?

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) is a promising procedure for the treatment of morbid obesity. The stomach is usually transected near the angle of His; hence, the lower esophageal sphincter (LES) may be affected with consequences on postoperative gastroesophageal reflux disease (GERD). The purpose of this study was to examine the effect of LSG on the LES and postoperative GERD.

METHODS

Severely obese asymptomatic patients submitted to LSG underwent esophageal manometry and GERD evaluation preoperatively and at least 6 weeks postoperatively. Data reviewed included patient demographics, manometric measurements, GERD symptoms, and pathology. Statistical analysis was performed by SPSS software.

RESULTS

Twelve male and eleven female patients participated in the study. Mean age was 38.5 ± 10.9 years, and initial body mass index was 47.9 ± 5.1 kg/m(2). At follow-up examination, mean excess body mass index loss was 32.3 ± 12.7%. The LES total and abdominal length increased significantly postoperatively, whereas the contraction amplitude in the lower esophagus decreased. There was an increase in reflux symptoms postoperatively (p < 0.009). The operating surgeon who mostly approximated the angle of His resulted in an increased abdominal LES length (p < 0.01). The presence of esophageal tissue in the specimen correlated with increased total GERD score (p < 0.05).

CONCLUSIONS

LSG weakens the contraction amplitude of the lower esophagus, which may contribute to postoperative reflux deterioration. It also increases the total and the abdominal length of the LES, especially when the angle of His is mostly approximated. However, if this approximation leads to esophageal tissue excision, reflux is again aggravated. Thus, stapling too close to the angle of His should be done cautiously.

Reinforcing the staple line during laparoscopic sleeve gastrectomy: prospective randomized clinical study comparing two different techniques. Preliminary results

BACKGROUND

Sleeve gastrectomy involves the creation of small gastric reservoir based on lesser curvature of the stomach, which is fashioned by a longitudinal gastrectomy that preserves the antrum and pylorus together with its vagal innervation. The main complications in the early postoperative course are bleeding and gastric leak. In order to reduce these complications the staple line can be reinforced in many different ways. The purpose of this study was to randomly compare two different techniques in laparoscopic sleeve gastrectomy (LSG): buttressing the staple line at the gastroesophageal junction (angle of Hiss) with Gore Seamguard and staple-line suturing with PDS 2.0.

METHODS

Between July 2009 and July 2010, 90 patients were prospectively and randomly enrolled in the two different techniques of handling the staple line during LSG. Forty-eight of these patients belonged in group A (application of Gore Seamguard) and 42 in group B (application of a continuous suture). Operative and postoperative complications were recorded.

RESULTS

Postoperative leak affected two patients in group A (4.2%) and bleeding occurred in one patient of group A (2%). Total complication rate was 6.2% for group A. No major surgical complication occurred in group B. The differences between the two groups did not reach statistical significance.

CONCLUSIONS

No significant difference is evidenced in terms of bleeding and postoperative leak between the two techniques of enhancing the staple line in LSG. Suturing of the staple line may be more time consuming but costs are considerably less.

OCT4 spliced variant OCT4B1 is expressed in human colorectal cancer

OCT4, a POU-domain transcription factor is considered to be a key factor in maintaining the pluripotency of stem cells. Several OCT4 isoforms are differentially expressed in human pluripotent and non-pluripotent cells. Reactivation of OCT4 expression is postulated to occur in differentiated cells that have undergone tumorigenesis. To examine OCT4 expression in colorectal cancer (CRC) tissues, and to assess the efficacy of OCT4 as a potential biomarker for CRC, in this study, we investigated its expression in CRC tissues, evaluated its relationship to various clinicopathological parameters and defined the isoform of OCT4 that was found to be expressed in CRC cases. Primary tumor tissues and matching adjacent non-cancerous tissues were obtained from 84 CRC patients. OCT4 expression and isoform determination were documented by reverse transcription-PCR and real-time PCR. OCT4, Sox-2, and NANOG localization were performed using immunohistochemistry. The isoforms expressed in the studied cases were confirmed by sequencing. Twenty biopsy specimens representing healthy tissues, retrieved from colonoscopy were studied in parallel as controls. OCT4 expression levels were higher in CRC tissues compared to matching, adjacent non-cancerous tissues, and healthy controls. Additionally, the levels of OCT4 expression in CRC tissues correlated with tumor stage. OCT4 and Sox-2 were localized in the nuclei and the cytoplasm of CRC cells. In all CRC cases, we found that the OCT4B1 isoform is expressed. Over-expression of OCT4B1 was found in poorly and moderately differentiated CRC tissues. In conclusion, the data imply that OCT4B1 isoform may represent a potential biomarker for the initiation, progression, and differentiation of CRC.

Stem cells in colon cancer. A new era in cancer theory begins

INTRODUCTION

Despite the various therapeutic combinations and the emergence of new targeted therapies, there is still no curative treatment for all stages of colorectal cancer. Through the query for the best possible combination and solution, a new theory approaching colorectal cancer as a stem cell disease appeared, with a continuously growing body of evidence supporting this idea. The inability to directly recognize cancer stem cells has led researchers to an attempt of distinguishing those using indirect markers.

DISCUSSION

This review focuses on colon cancer stem cell theory, the various findings supporting and contradicting this hypothesis, and the markers used up to now in characterizing stem cell populations in colorectal cancer. Despite the numerous unanswered questions on this new cancer hypothesis, it appears to have a justifiable role to play in colorectal cancer tumor biology, and furthermore, it may be the basis for the development of new therapeutic agents of the future. Therefore, every surgeon, oncologist, and physician who is implicated with this disease should be familiar with this novel colorectal cancer theory.

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.

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.

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.

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.

Short-term effect of orlistat on dietary glycotoxins in healthy women and women with polycystic ovary syndrome

Exogenous advanced glycation endproducts (AGEs, known atherogenic molecules) abundant in everyday precooked, rich in fat, overheated meals can possibly contribute to the increased risk for diabetes and cardiovascular disease in women with polycystic ovary syndrome (PCOS). The aim of the present study was to investigate the effect of a lipase inhibitor on absorbed food glycotoxins in healthy women and those with PCOS. A 2-day protocol was followed. In the first day, a meal rich in AGE was provided, which on the second day was followed by two 120-mg capsules of lipase inhibitor, orlistat. Serum AGE levels were evaluated at baseline (0 hours), and at 3 and 5 hours postmeal during the study. Thirty-six women were studied, 15 controls (mean age, 28.80 +/- 5.47 years; body mass index, 25.85 +/- 6.73 kg/m(2)) and 21 with PCOS (mean age, 25.29 +/- 5.06 years; body mass index, 30.40 +/- 7.51 kg/m(2)) (University Hospital, Athens, Greece, institutional practice). Serum AGE levels, on day 1, were significantly increased both in the control group and in the PCOS group as compared with basal values (control group, 14.1%; PCOS group, 6.0%; P < .001). The corresponding rise was significantly lower on day 2 when the same meal was combined with orlistat (control group, 4.1%; PCOS group, 2.0%; P < .01). A limitation of the study is that it is a nonplacebo, nonrandomized therapeutic trial where each subject is considered as its own control. In conclusion, this study demonstrated the beneficial effect of orlistat on the absorption of food glycotoxins.

Erythropoietin abuse and erythropoietin gene doping: detection strategies in the genomic era

The administration of recombinant human erythropoietin (rhEPO) increases the maximum oxygen consumption capacity, and is therefore abused as a doping method in endurance sports. The detection of erythropoietin (EPO) abuse is based on direct pharmacological and indirect haematological approaches, both of which have several limitations. In addition, current detection methods cannot cope with the emerging doping strategies of EPO mimicry, analogues and gene doping, and thus novel detection strategies are urgently needed. Direct detection methods for EPO misuse can be either pharmacological approaches that identify exogenous substances based on their physicochemical properties, or molecular methods that recognise EPO transgenes or gene transfer vectors. Since direct detection with molecular methods requires invasive procedures, it is not appropriate for routine screening of large numbers of athletes. In contrast, novel indirect methods based on haematological and/or molecular profiling could be better suited as screening tools, and athletes who are suspect of doping would then be submitted to direct pharmacological and molecular tests. This article reviews the current state of the EPO doping field, discusses available detection methods and their shortcomings, outlines emerging pharmaceutical and genetic technologies in EPO misuse, and proposes potential directions for the development of novel detection strategies.

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.

Hyperandrogenemia: pathophysiology and its role in ovulatory dysfunction in PCOS

The most common hormonal disorder that infertile women suffer from is hyperandrogenemia, a disorder believed to show its first signs even from puberty. We discuss the impact of hyperandrogenemia on the normal ovary as well as its potential role and contribution to anovulation and infertility. The early diagnosis and management of hyperandrogenemia in women has been proved to be essential for their health and fertility.

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.