Genetic architecture of 11 organ traits derived from abdominal MRI using deep learning

Cardiometabolic diseases are an increasing global health burden. While socioeconomic, environmental, behavioural, and genetic risk factors have been identified, a better understanding of the underlying mechanisms is required to develop more effective interventions. Magnetic resonance imaging (MRI) has been used to assess organ health, but biobank-scale studies are still in their infancy. Using over 38,000 abdominal MRI scans in the UK Biobank, we used deep learning to quantify volume, fat, and iron in seven organs and tissues, and demonstrate that imaging-derived phenotypes reflect health status. We show that these traits have a substantial heritable component (8-44%) and identify 93 independent genome-wide significant associations, including four associations with liver traits that have not previously been reported. Our work demonstrates the tractability of deep learning to systematically quantify health parameters from high-throughput MRI across a range of organs and tissues, and use the largest-ever study of its kind to generate new insights into the genetic architecture of these traits.

Diagnostic value of multi-slice spiral CT (MSCT) combined with digestive tract angiography in gastric fundus cardia carcinoma

PURPOSE

To evaluate the diagnostic value of multi-slice spiral CT (MSCT) combined with digestive tract angiography in patients with gastric fundus cardia carcinoma.

METHODS

A total of 185 patients with suspected gastric fundus cardia carcinoma admitted in our hospital were collected. Among them, 93 patients were examined with MSCT combined with digestive tract angiography and were enrolled in the research group. Another 92 patients examined by MSCT alone comprised the control group. The diagnostic value of MSCT combined with digestive tract angiography in patients with gastric fundus cardia carcinoma was investigated. 185 patients were diagnosed by pathological examination and 166 had gastric fundus cardia carcinoma, with 84 patients in the research group, and 84 patients in the control group. Fifty nine patients with gastric fundus cardia carcinoma in the control group were diagnosed by MSCT.

RESULTS

There were significant differences compared with pathological diagnosis (p<0.05). Eighty-two patients with gastric fundus cardia carcinoma in the research group were diagnosed by MSCT combined with digestive tract angiography. There were no significant differences compared with pathological diagnosis (p>0.05). Sensitivity, specificity and accuracy of the research group were significantly higher than those of the control group (p<0.05). The detectable rate in imaging results of the research group was higher than that of the control group (p<0.05).

CONCLUSION

MSCT combined with digestive tract angiography is more accurate than single MSCT in the diagnosis of gastric fundus cardia carcinoma, which can effectively reduce the misdiagnosis and missed diagnosis and is worthy of clinical promotion.

Multivisceral robotic resection: a glimpse into the future of minimally invasive abdominal surgery

A 62-year-old man was referred to the Hepato-Pancreato-Biliary (HPB) surgeons with left upper quadrant discomfort. The initial investigations and CT scans revealed a tumour in the pancreatic tail with liver metastases, confirmed on MRI. It was initially thought to be an adenocarcinoma; however, further investigations found that it was a grade 1 neuroendocrine tumour with Ki 67 at 1% and it was agreed that he would undergo a total robotic surgery involving resection of the locally advanced tumour of the tail of pancreas, with the involvement of the stomach, and splenic flexure of the colon with liver metastases. The resulting procedure was a total robotic distal pancreatectomy, splenectomy, sleeve resection of stomach, cholecystectomy, atypical resection of two liver lesions and microwave ablation of multiple liver lesions. Four days post-operatively, he was discharged from hospital and commenced adjuvant chemotherapy. He currently enjoys a good quality of life.

Judging the J pouch: a pictorial review

Restorative total proctocolectomy with ileal pouch-anal anastomosis is the surgery of choice for patients with medically refractory ulcerative colitis, ulcerative colitis with high-grade dysplasia or multi-focal low-grade dysplasia, and for patients with familial adenomatous polyposis. The natural history of the surgery is favorable, and patients generally experience improved quality of life and acceptable long-term functional outcome. However, some patients experience significant long-term morbidity from early and/or late pouch-related complications. When complications arise, radiologists must understand the advantages and disadvantages of the various imaging modalities that can be used to assess the pouch. Radiologist familiarity with the surgical technique, pouch anatomy, and imaging appearance of the various potential early and late complications will help facilitate appropriate clinical and surgical decision-making. This review provides an anatomic-based imaging review of the pouch and pouch-related complications, including numerous illustrative fluoroscopic and cross-sectional imaging examples.

Imaging of Gastrointestinal and Abdominal Emergencies in Binge Drinking

Excess alcohol consumption is a leading cause of preventable morbidity and mortality globally. The pattern of consumption of alcoholic beverages has changed in our society in the recent past, with binge drinking becoming more and more common, especially among young adults. Abdominal pain following alcohol consumption can be secondary to a wide range of pathologies, the treatment algorithm of which can range from medical supportive treatment to more invasive life-saving procedures such as transarterial embolization and emergency laparotomy. Correct diagnosis, differentiation among these conditions, and implementing the correct management algorithm is heavily reliant on accurate and appropriate imaging. We review the pathophysiology, clinical presentation, imaging features and management options of acute abdominal emergencies secondary to binge drinking, based on a selection of illustrative cases.

Indirect percutaneous core needle biopsy of solid pancreatic or peripancreatic lesions

Solid pancreatic or peripancreatic lesions comprise a heterogeneous group of diseases that rely on a multimodality imaging approach for subsequent tissue procurement. Endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA)/biopsy is an effective and safe method for tissue diagnosis in this region. The failure to obtain adequate tissue for diagnosis under EUS guidance is still a rare but important issue. Percutaneous core needle biopsy (CNB) provides an alternative pathway for adequate specimen acquisition. Because of the deep retroperitoneal location, the percutaneous biopsy of pancreatic or peripancreatic lesions may inevitably pass through visceral organs. The procedure is relatively risky and difficult for general radiologists, particularly beginners, and an adequate knowledge of the abdominal anatomy and biopsy technique is indispensable. In this review, various aspects of percutaneous CNB for solid pancreatic or peripancreatic lesions using different trans-organ approaches are reviewed to increase the chance of successful biopsy.

Micro-computed tomography visualization of the vestigial alimentary canal in adult oestrid flies

Oestrid flies (Diptera: Oestridae) do not feed during the adult stage as they acquire all necessary nutrients during the parasitic larval stage. The adult mouthparts and digestive tract are therefore frequently vestigial; however, morphological data on the alimentary canal in adult oestrid flies are scarce and a proper visualization of this organ system within the adult body is lacking. The present work visualizes the morphology of the alimentary canal in adults of two oestrid species, Oestrus ovis L. and Hypoderma lineatum (de Villiers), with the use of non-invasive micro-computed tomography (micro-CT) and compares it with the highly developed alimentary canal of the blow fly Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae). Both O. ovis and H. lineatum adults showed significant reductions of the cardia and the diameter of the digestive tract, an absence of the helicoidal portion of the midgut typical of other cyclorrhaphous flies, and a lack of crop and salivary glands. Given the current interest in the alimentary canal in adult dipterans in biomedical and developmental biology studies, further understanding of the morphology and development of this organ system in adult oestrids may provide valuable new insights in several areas of research.

Automatic Multi-Organ Segmentation on Abdominal CT With Dense V-Networks

Automatic segmentation of abdominal anatomy on computed tomography (CT) images can support diagnosis, treatment planning, and treatment delivery workflows. Segmentation methods using statistical models and multi-atlas label fusion (MALF) require inter-subject image registrations, which are challenging for abdominal images, but alternative methods without registration have not yet achieved higher accuracy for most abdominal organs. We present a registration-free deep-learning-based segmentation algorithm for eight organs that are relevant for navigation in endoscopic pancreatic and biliary procedures, including the pancreas, the gastrointestinal tract (esophagus, stomach, and duodenum) and surrounding organs (liver, spleen, left kidney, and gallbladder). We directly compared the segmentation accuracy of the proposed method to the existing deep learning and MALF methods in a cross-validation on a multi-centre data set with 90 subjects. The proposed method yielded significantly higher Dice scores for all organs and lower mean absolute distances for most organs, including Dice scores of 0.78 versus 0.71, 0.74, and 0.74 for the pancreas, 0.90 versus 0.85, 0.87, and 0.83 for the stomach, and 0.76 versus 0.68, 0.69, and 0.66 for the esophagus. We conclude that the deep-learning-based segmentation represents a registration-free method for multi-organ abdominal CT segmentation whose accuracy can surpass current methods, potentially supporting image-guided navigation in gastrointestinal endoscopy procedures.

Role of Computed Tomography in Staging and Management of Gastrointestinal Lymphoma

Twenty-six computed tomography (CT) examinations in 18patients with histologically proven gastrointestinal lymphomas are reported. Fourteen CT examinations were performed at the time of initial presentation, the others being performed during the course of the disease. CT did not help in the diagnosis of the disease but it is effective in assessing the extent and thus the stage of the disease. A normal CT scan during follow up is associated with good prognosis. CT may be of help in planning treatment, especially radiotherapy. It is an investigation easily tolerated by patients and can be used in circumstances where other investigations would be impossible.

Ex vivos models to teaching therapeutic endoscopic ultrasound (T-EUS)

BACKGROUND

Endoscopic ultrasound training has a learning curve greater than the other endoscopic therapeutic techniques. One of the preclinical teaching methods is the use of ex vivo porcine models.

AIM

To describe five ex vivo porcine models for training in therapeutic echoendoscopic procedures.

MATERIALS AND METHODS

Using porcine digestive tract containing esophagus, stomach, duodenum, spleen, liver and gallbladder, five models for therapeutic echoendoscopy training were described. With other segments of the porcine pieces (such as the bladder, spleen segment and omentum segment) and with easily accessible materials (such as grape and ultrasound gel), lesions were simulated to be treated. These models were applied in the Hands on course at the IRCAD (Institut de recherche contre les cancers de l'appareil digestif) Barretos of 2017. Endoscopic equipment and instruments are the same as those used in clinical practice.

RESULT

The models are easily reproducible and do not require exchange during the hands on course period. Endoscopic and echographic imaging and tactile sensitivity are similar to the real one.

CONCLUSION

The models described in this study demonstrated to be realistic, easy to reproduce and allow repetition during the same session. However, comparative studies are necessary to verify the real impact on teaching.

Quantification of fluorescence angiography in a porcine model

PURPOSE

There is no consensus on how to quantify indocyanine green (ICG) fluorescence angiography. The aim of the present study was to establish and gather validity evidence for a method of quantifying fluorescence angiography, to assess organ perfusion.

METHODS

Laparotomy was performed on seven pigs, with two regions of interest (ROIs) marked. ICG and neutron-activated microspheres were administered and the stomach was illuminated in the near-infrared range, parallel to continuous recording of fluorescence signal. Tissue samples from the ROIs were sent for quantification of microspheres to calculate the regional blood flow. A software system was developed to assess the fluorescent recordings quantitatively, and each quantitative parameter was compared with the regional blood flow. The parameter with the strongest correlation was then compared with results from an independently developed algorithm, to evaluate reproducibility.

RESULTS

A strong correlation was found between regional blood flow and the slope of the fluorescence curves (ROI I: Pearson r = 0.97, p < 0.001; ROI II: 0.96, p < 0.001) as the normalized slope (ROI I: Pearson r = 0.92, p = 0.004; ROI II: r = 0.96, p = 0.001). There was acceptable correlation of the slope of the curve between two independently developed algorithms (ROI I+II: Pearson r = 0.83, p < 0.001), and good resemblance was found with the Bland-Altman method, with no proportional bias.

CONCLUSIONS

Perfusion assessment with quantitative indocyanine green fluorescence angiography is not only feasible but easy to perform with commercially available equipment and readily accessible software.

Ultrasound: "one stop shop" in hepatology

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FOREIGN BODY IN THE NASOPHARYNX; MASQUERADING AS PHARYNGOTONSILLITIS

Foreign body (FB) in the aerodigestive tracts has been commonly reported but findings of impacted foreign bodies in the nasopharynx following inhalation/ingestion are very rare. Most of the FB gets lodged as a result of forceful vomiting, coughing,and digital manoeuvres for removal of FB in the oropharynx. Several objects have been identified lodged in the nasopharynx. No age group is spared although most victims are children under 10 years of age. Foreign bodies in the nasopharynx can be uneventful or potentially dangerous depending on type, size and location as it may cause sudden airway obstruction, or local pressure necrosis of alimentary or respiratory tract or both. Presentation in children is usually with a history of swallowed FB which may not be witnessed in children, choking, cough, bluish discolouration, breathlessness, drooling of saliva, halitosis, rhinorrhoea, snoring, stridor, dysphagia, vomiting and dysphonia. A foreign body in the nasopharynx is a challenge to patient, parents, the physician and the ENT surgeon, as it may be miss-diagnosed, in the index case, as Pharyngotonsilitis. The index patient, a 14 month child,was presented with a two days history of fever, drooling of saliva, mouth breathing, and digital manipulation. Lateral imaging of the post nasal space following initial treatment with antibiotics, aided the diagnosis of a periwinkle shell in the nasopharyngx that was removed during a nasopharyngoscopy under general anaesthesia without complication and subsequently discharged home. This emphasizes a high index of suspicion for FB in the nasopharynx in children with history of missing foreign body, digital manipulation, drooling of saliva and mouth breathing. Lateral X-ray of the postnasal space, neck, chest and abdomen should be the minimum investigation required.

How to perform EUS in the pancreaticobiliary area

EUS remains mandatory in the management of the majority of pancreaticobiliary diseases. This article fully describes with details how to examine the pancreatico-biliary region using radial and linear EUS. Pancreaticobiliary examination with a radial instrument: 1) place the patient on left lateral decubitus position, tilted towards the examination table at an angle of 30° to 40°; 2) use a moderately inflated balloon; 3) begin the examination in the stomach 45 to 50 cm from the incisors, to examine the body and tail region; 4) after advancing through the pylorus under endoscopic control, proceed from the bulb to the second part of the duodenum by pushing the echoendoscope which is in opened position of the handle gently under ultrasound control, turning the handle clockwise if the superior duodenal angle is open, then push the echoendoscope in the long position towards the ampulla of Vater, adding up angulation. Use the ERCP withdrawal manoeuvre under endoscopic control, from the apex of the bulb if the superior duodenal angle is closed (thin patient), and allow the head of the echoendoscope to fall into the second duodenum, then push the tip over the ampulla of Vater, in the long position, and start the examination at this point. Pancreaticobiliary examination with a linear instrument: place the patient in the same position as with a radial instrument. 1) balloon slightly inflated or uninflated; 2) use the neutral position of the handle as a starting point in the stomach. Move from this position to the open position by turning the handle anti-clockwise and to the closed position by turning the handle clockwise while advancing or withdrawing the echoendoscope, adding clockwise torquing to the endoscope shaft when necessary (to examine the pancreatic tail); 3) almost the whole of the pancreatic gland, apart from the juxtaduodenal segment of the head and uncinate process and in particular the ampulla of Vater, can be examined through the stomach; 4) the examination is conducted exclusively by following the vascular structures and ducts, hence the importance of anatomical knowledge; 5) use constant up angulation.

[Foreign body ingestion: a common problem in paediatric age]

Foreign body (F.B.) ingestion occurs very frequently in paediatric age. The kind of ingested foreign bodies depends on the patient's age. Children between 1 and 3 years of age mostly swallow coins, toy parts, stones and small batteries; instead, older children typically ingest boluses of meat. The aim of this study is to review our case histories according to the latest literature, focusing on some events that needed a therapeutic emergency treatment.

Foreign body ingestion in Turkish children

Foreign body ingestion (FBI) is a common problem in the pediatric population. Even though morbidity and mortality due to foreign body ingestion are rare in childhood, they may cause serious anxiety in parents. We aimed to analyze the clinical presentation, etiology and management strategy of FBI in children in our country. Records of children admitting with a history of FBI over a three-year period were reviewed retrospectively. Data regarding gender, age, type of the ingested body, management strategy and outcome of the patients were recorded. Of 176 children, 98 (55.6%) were male. Mean age +/- SD of the patients was 3.75 +/- 4.25 years, and most of the patients were below four years of age (71.5%). Most of the children (64.7%) were seen within 48 hours, and most were asymptomatic. Blue beads attached to a safety pin (a cultural good luck charm) (38.6%), coins (27.8%) and turban pins (18.1%) were the most commonly observed foreign bodies. The blue beads/safety pin were found to be ingested primarily by infants, while ingestion of turban pins was mostly seen in adolescent girls who covered their heads. Localization of the foreign bodies was in the distal small intestine, stomach and esophagus in 61.4%, 23.8% and 14.7% of the cases, respectively. Sixty-nine endoscopic interventions were performed in 61 patients (34.6%), and these accounted for 7.3% of all endoscopic interventions during the three-year period. No major complication was observed during the procedure, and none of the patients underwent surgery. The frequently used accessory devices were retrieval net basket (57.9%), snare for pins (17.3%), tripod forceps and rat-tooth forceps. The blue beads/safety pin and turban pin were the commonly ingested foreign bodies in our center due to cultural factors. Education of the parents and of adolescent girls should greatly reduce the incidence of FBI. Endoscopic removal is safe without any major complications.

The fine structure of the midgut in the mite Anystis baccarum (L.) (Acari, Actinedida: Anystidae)

The ventriculus and the midgut caeca of the fed females of Anystis baccarum (L.) were investigated by using light and electron microscopy. In addition to the main type of polyfunctional digestive cells, special secretory cells were detected in the anterior region of the ventriculus. The shape and the ultrastructure of the digestive cells vary depending on their physiological state. Intracellular digestion, absorption or excretion processes prevail at different stages of the cell cycle. The secretory cells are characterized by the presence of extensive rough endoplasmic reticulum, filling whole space of the cell. These cells do not contain the apical network of pinocytotic canals, which are typical for the digestive cells. Three types of secretory granules were found in the cytoplasm of the secretory cells that probably correspond to three sequential stages of granulogenesis. The primary secretory granules are formed by the fusion of Golgi vesicles. The primary granules fuse to form complex vesicles with heterogeneous contents. These secondary granules aggregate to form very large inclusions of high electron density (tertiary secretory granules), which probably represent the storage of the secretory product. All types of secretory granules were observed close to the apical plasmalemma.

Alveolar hydatid disease of the liver: brief review and spectrum of adjacent organ invasion

The purpose of this study is to show the spectrum of adjacent organ invasion and to make a brief review of hepatic alveolar hydatid disease (AHD), using CT and MR imaging. We retrospectively reviewed CT and MR images of three patients with various adjacent organ invasions surgically and histologically proven to be AHD. Local invasion to right kidney and adrenal, right hemidiaphragm and lung were detected in one patient, right adrenal in another patient and gall bladder, duodenum, gastric wall and pancreas invasion in the other. AHD may rarely extend to the gall bladder, stomach, duodenum, pancreas, right adrenal and kidney, diaphragm, pleura and lung. The extension of the disease outside the liver is usually encountered in patients with large, peripherally located masses in the advanced stage of the disease.

[State of the abdominal organs and vessels on the background of simulated venous plethora in the splanchnic vascular system]

Ultrasonic investigations of the abdominal organs and splanchnic veins were performed in essentially healthy subjects tilted at 12 degrees and 15 degrees for the period of 12 hrs. and 24 hrs. Tilting produced typical redistribution of venous blood and body liquids toward the cranial end. In its turn, blood redistribution caused excessive venous plethora and abdominal stasis. These were succeeded by expansion of large veins in the abdomen, enlargement of parenchymal organs and contraction of their echogenicity, and thickening of the hollow organs walls. Changes in the gastrointestinal functions before meal included elevated gastric, hepatic and pancreatic secretion, and an increased amount of intestinal content. The investigations demonstrated that stasis of the splanchnic veins altered functioning of the digestive organs in tilted human subjects.

Blunt abdominal trauma: current imaging techniques and CT findings in patients with solid organ, bowel, and mesenteric injury

Imaging plays a critical role in the evaluation of patients with blunt abdominal trauma. In most institutions, computed tomography (CT) is the modality of choice when evaluating such patients. The purpose of this review is to highlight current techniques in trauma imaging and to review CT findings associated with solid organ, bowel, mesenteric, and diaphragmatic injury. In particular, emphasis is placed on the use of multidetector CT technology (MDCT), especially 64-row detector CT. The role of various techniques, including the use of oral and intravenous contrast, as well as the potential benefit of delayed imaging, is discussed.

Role of Radiology in a National Initiative to Interdict Drug Smuggling: The Dutch Experience

OBJECTIVE

The purpose of this pictorial essay is to describe the role of radiology in a national initiative to intercept illegal narcotics concealed within the bodies of human transporters.

CONCLUSION

Radiologic examination is increasingly important in identifying intracorporeal drug smuggling as improved wrapping techniques undermine the usefulness of blood and urine testing and clinical observation. Detection rates of high accuracy, sensitivity, and specificity are achieved by experienced radiologists.

[The value of three-dimensional 64-multi-slices helical computer tomography on the diagnosis of diseases of digestive system]

OBJECTIVE

To study the value of three-dimensional 64-slice helical computer tomography (64-MSCT) in diagnosis and surgical treatment on diseases of digestive system.

METHODS

From November 2005 to August 2006, 64-MSCT was performed on 102 patients suspected of digestive diseases to display foci of infection, hepatic conduit, biliary-pancreatic duct and portal venous system, followed by three-dimensional reconstruction of those targets. The reconstructed images as well as the data obtained from the reconstruction were compared with the surgical results.

RESULTS

Twenty-five of 27 patients with portal hypertension (PHT) showed blur-free imaging of main portal vein (MPV) while the other 2 cases showed congenital cavernous transformation or thrombogenesis of MPV. Compensatory circulation of portal venous system was displayed satisfactorily in 27 cases. The three-dimensionally reconstructed images of 34 cases of hepatocellular carcinoma (HCC) demonstrated no invasion of tumors into the tissues and blood vessels of 23 cases, visible invasion into portal vein and hepatic veins of 9 cases, tumor embolus in portal veins of 1 case, and arterio-venous fistula in only one case. The 3D imaging of biliary passages displayed total concretion, tumor and constrictive or dilated biliary-pancreatic duct and bile duct around amphi-obstruction, which complied with the operations research of calculus of bile duct in 25 cases, cholangiocarcinoma in 5 cases, and cancer of pancreas in 5 cases. Operations research in accordance with the 3D reconstructed imaging accorded with imaging diagnosis in respect of PHT, HCC and diseases of biliary-pancreatic system at the rates of 100%, 97% and 100%, respectively.

CONCLUSIONS

Three-dimensional 64-MSCT displays foci of infection and constructions of biliary-pancreatic duct and hepatic conduit stereoscopically.

[Metabolic syndrome in patients with gastrointestinal diseases]

AIM

To study gastrointestinal pathology in patients with metabolic syndrome (MS).

MATERIAL AND METHODS

The examination of 536 patients with MS and gastrointestinal diseases included clinical tests, biochemical hepatic tests, determination of blood lipid spectrum, x-ray of the esophagus, stomach, duodenum, colon, esophagogastroduodenoscopy, ultrasonic investigation of the liver, gall bladder and pancreas. 56 patients have undergone puncture biopsy of the liver.

RESULTS

Esophageal, hepatic and biliary, pancreatic, colon diseases were detected in 72, 64, 18 and 74%, respectively. Clinical manifestations of these associated diseases had no definite symptoms and were characterized by cross-over syndromes.

CONCLUSION

MS patients with gastrointestinal diseases showed polymorbidity. Treatment of the above diseases should be supplemented with drug correction of MS.

Foreign bodies in the aerodigestive tract--a clinical study of cases in the coastal belt of South India

PURPOSE

To investigate the cases of foreign body in the aerodigestive tract and to elucidate the characteristic problems in India.

DESIGN AND SETTING

Three hundred patients presenting with a history of either aspirating or swallowing a foreign body were analyzed in a tertiary care center. Data were collected by retrospective chart review and statistically analyzed.

RESULTS

Of the 300 patients studied, 90% (270 cases) did have a retained foreign body, with 233 (86.2%) cases found in the pharyngoesophagus and 37 (13.7%) cases in the tracheobronchial tree. With foreign bodies in the tracheobronchial passages, the most common sign and symptom were rhonchi (50%) and dyspnea (67%), respectively; in pharyngoesophagus, the most common symptom and sign were dysphagia (64%) and odynophagia (45%), respectively. The most common foreign body found was fish bone in 39% (106 cases) and the most common site of lodgment was the cervical esophagus 50.5% (136 cases). Rigid endoscopy with forceps removal under general anesthesia was the main treatment modality. Thirty-three (12.2%) cases had complications secondary to retained foreign body.

CONCLUSION

Foreign bodies in the aerodigestive tract continue to be a common problem affecting adults and children alike. Rigid endoscopies with forceps removal under general anesthesia are the preferred management modality. From their experience, the authors recommend that no foreign body in the upper aerodigestive tract should be left alone with the hope that it will come out spontaneously. Delay in diagnosis and management can lead to life-threatening complications.

Gastrointestinal infection in the immunocompromised (AIDS) patient

In the past two decades acquired immunodeficiency syndrome (AIDS) has become one of the most devastating illnesses in human history. As the epidemic continues to spread increasingly, AIDS patients are no longer confined to a few specialized AIDS hospitals and are now seen in general hospitals and clinics everywhere. Radiologists need to recognize the appearances, to understand how-safely-to care for patients with this disease, and to know enough about the illness to be able to counsel their patients. This article presents a review of current knowledge about the wide range of gastrointestinal hepatic, splenic, biliary, and retroperitoneal manifestations in AIDS, and how the role of modern medical imaging techniques and diagnosis and treatment can be applied. The imaging aspects (conventional double-contrast gastrointestinal studies, ultrasound, CT, and MR) of the diseases of the luminal gastrointestinal tract, liver, spleen, biliary tract, and retroperitoneum will be systematically discussed. Candidiasis, herpes, cytomegalovirus, cryptosporidiosis, histoplasmosis, isosporiasis, salmonellosis, toxoplasmosis, unusual mycobacteria, and viral infections account for the majority of non-neoplastic disorders.

Advances in alimentary tract imaging

Advances in imaging techniques are changing the way radiologists undertake imaging of the gastrointestinal tract and their ability to answer questions posed by surgeons. In this paper we discuss the technological improvements of imaging studies that have occurred in the last few years and how these help to better diagnosing alimentary tract disease.

Eponyms in Radiology of the Digestive Tract: Historical Perspectives and Imaging Appearances

Eponyms are a means of honoring individuals who have made lasting contributions to medicine. Eponyms are frequently encountered in the field of radiology, especially radiology of the digestive tract. However, the use of eponyms may fail to convey a precise meaning or definition and could result in miscommunication. Furthermore, in some instances, more than one individual may have contributed to the discovery or description of a particular structure or disease, whereas in others, an eponym may have been incorrectly applied and then propagated for years thereafter in the medical literature. Still, eponyms are a means of honoring those who have made important discoveries and observations, and familiarity with these terms is important for proper reporting and accurate communication. Moreover, the acquisition of some historical knowledge about the individuals whose names are associated with various structures or diseases helps restore some humanity to the science of medicine.

[Scintigraphic procedures in internal medicine--indications, limits, possibilities]

Scintigraphy continues to play an important diagnostic role in internal medicine. Many diagnostic questions can only be answered with scintigraphic methods. The application of specific radiopharmaceutical tracers offers the unique possibility to visualize ongoing functional changes, associated with diseases concerning internal medicine. The diagnostic potential of modern scintigraphic procedures such as PET for internal medicine is not yet sufficiently used and will continue to grow with hybrid systems, such as PET-CT and SPECT-CT.

Giant cystic abdominal masses in children

In this pictorial essay the common and uncommon causes of large cystic and cyst-like abdominal masses in children are reviewed. We discuss and illustrate the following: mesenchymal hamartoma, choledochal cyst, hydrops of the gallbladder, congenital splenic cyst, pancreatic pseudocyst, pancreatic cystadenoma, hydronephrosis, multicystic dysplastic kidney, multilocular cystic nephroma, adrenal hemorrhage, mesenteric and omental cysts, gastrointestinal duplication cyst, meconium pseudocyst, ovarian cysts and cystic neoplasms, hematocolpos, urachal cysts, appendiceal abscess, abdominal and sacrococcygeal teratoma, and CSF pseudocyst. We also describe imaging features and clues to the diagnosis.

The possible diagnostic role of endoscopic ultrasound in patients with dyspepsia

BACKGROUND

Dyspepsia is common in clinical practice with frequent relapses and often requires multiple investigations to assess intraluminal and extraluminal etiologies. Endoscopic ultrasound (EUS) has the potential of serving both purposes in a single setting.

MATERIAL AND METHOD

Patients with dyspepsia who underwent EUS in four-year period were retrospectively reviewed. Diagnostic findings of US, final diagnoses were noted and compared with the reference standards.

RESULTS

131 patients with a mean age +/- SD of 50 +/- 12.7 years were included. The common diagnoses were non-ulcer dyspepsia in 56%, symptomatic gallstone (GS) in 22.9%. EUS detected two GS missed by transabdominal ultrasound (TUS). EUS missed one GS documented by surgery. EUS detected seven cases of ERCP-proven CBD stones undetected by TUS and had a sensitivity, specificity, positive predictive value and negative predictive value for CBD stones of 87.5%, 91.7%, 87.5%, and 91.7% respectively.

CONCLUSION

EUS is a potential investigation for the management of dyspepsia.

Agony of the ecstasy: Report of five cases of MDMA smuggling

The international smuggling of illicit drugs by the ingestion or rectal insertion of drug-filled packages is recognized in the trafficking of heroin and cocaine. Customs authorities, with suspicion of such activities, presented five subjects. The legally allowed radiological examination comprising one supine abdominal radiograph was performed. Radiographic findings demonstrated the presence of multiple enteric oval, capsule-shaped packages of soft tissue density. This was confirmed following supervised evacuation of bowel contents induced by the administration of laxatives. Analysis of the concealed material identified ecstasy (methylenedioxymethamphetamine (MDMA)), a substance not previously reported as transported by this route.

Diagnostic value of tissue harmonic imaging compared with conventional sonography

The purpose of this study was to determine if tissue harmonic imaging (THI) produced diagnostic images more frequently than conventional sonography. A prospective study was performed on 33 patients, to compare the diagnostic value of THI with conventional sonography. Each examination was performed using THI (transmit frequency=2.0 MHz, receive frequency=4.0 MHz) and conventional sonography at 2.5 and 4.0 MHz. The different sonographic techniques were then graded as to whether they produced diagnostic images. THI produced diagnostic images in 33 of 33 examinations (100%), 2.5 MHz conventional sonography produced diagnostic images in 26 of 33 examinations (79%), and 4.0 MHz conventional sonography produced diagnostic images in 26 of 33 examinations (79%). THI produced diagnostic images significantly more frequently than 2.5 MHz conventional sonography (p=.0233) and 4.0 MHz conventional sonography (p=.0233). The THI technique produced diagnostic images more frequently than conventional sonography.

The management of indeterminate incidental findings detected at abdominal CT

Abdominal computed tomography (CT) scans often have findings that are incidental to the reason the study was ordered. Several recent studies and reviews have addressed how these findings should be managed. This article summarizes current management strategies for several types of lesions that are commonly encountered. Some of these findings can be characterized without additional imaging (including simple renal cyst, angiomyolipoma, hepatic steatosis). Other findings are indeterminate. While some of these indeterminate incidental findings can be ignored based on statistical arguments (for example, a sharply circumscribed homogeneous low-attenuation renal lesion under 1 cm in patients without a predisposition to develop renal cell carcinoma), many may need additional imaging studies to either characterize them or demonstrate stability over time. Adhering to these strategies will hopefully reduce overutilization of imaging services while directing attention to those findings which need diagnostic or therapeutic interventions.

Hepatobiliary imaging after pancreaticoduodenectomy--a comparative study on Billroth I and Billroth II reconstruction

BACKGROUND/AIMS

This study was conducted to compare the passage of bile through the remnant alimentary tract following pancreaticoduodenectomy in patients undergoing Billroth I (Imanaga) and Billroth II (Child) reconstructions, using biliary scintigraphy.

METHODOLOGY

Seven normal human volunteers and 18 patients underwent Child's operation (n=10), or Imanaga's operation (n=8) using hepatobiliary scintigraphy.

RESULTS

In patients who underwent Child's operation (n=10), hepatobiliary scintigraphy showed a prominent stasis of bile tracer in the proximal jejunal loop and a significant time delay occurred at the upper jejunum. The time taken before visualization of 99mTc at the upper jejunum in the patient who underwent Child (65 +/- 5 min) was significantly longer than that in the healthy controls. On the other hand, in the patients who underwent Imanaga's operation (n=8) no bile stasis in the proximal jejunal loop was found and the time taken before visualization of 99mTc of the upper jejunum was similar to that of healthy controls (n=7). Continuous stasis of bile in the proximal loop in patients who undergo Child's operation can therefore cause reflux cholangitis and absorptive disturbances postoperatively in the long term.

CONCLUSIONS

The results of this study suggest that Imanaga's reconstruction is a more physiological procedure than Child's reconstruction following pancreaticoduodenectomy.

Analysis of acute toxicity with use of transabdominal ultrasonography for prostate positioning during intensity-modulated radiotherapy

OBJECTIVES

To analyze the effects of the B-mode ultrasound acquisition and targeting (BAT) system for positioning of patients with prostate cancer receiving intensity-modulated radiotherapy on acute gastrointestinal (GI) and genitourinary (GU) toxicity.

METHODS

The records of 50 consecutive patients treated using the BAT system were reviewed. Additionally, a comparison (no-BAT) group (ie, a group without a BAT study) treated in a similar manner was identified. The no-BAT group consisted of 49 patients treated immediately before the BAT group. For the two groups, the target definitions and dose prescriptions were identical, the treatment plan acceptance criteria were identical, and intensity-modulated radiotherapy was used for all patients. The daily BAT movements were charted in each of the three principal directions. Acute toxicity was scored for all patients according to the Radiation Therapy Oncology Group GI and GU acute toxicity scales.

RESULTS

The GU toxicity rates for the BAT versus no-BAT groups were grade 0 in 20% versus 14%; grade 1 in 38% versus 47%; grade 2 in 38% versus 39%; and grade 3 in 4% versus 0%, respectively (P = 0.284). The corresponding GI toxicity rates were grade 0 in 42% versus 27%; grade 1 in 28% versus 29%; and grade 2 in 30% versus 45% (P = 0.040). The incidence of GU and GI toxicity did not correlate with the directions or size of the BAT moves. Regression analysis revealed that for acute GI toxicity, the only variable reaching statistical significance was BAT use; no variable, including BAT use, reached statistical significance for acute GU toxicity.

CONCLUSIONS

The use of the BAT system did not change the rate of acute GU toxicity but did reduce the rate of acute GI toxicity.

Patient doses for barium meal examination in Serbia and Montenegro and potentials for dose reduction through changes in equipment settings

Patient doses for barium meal examination performed at three general hospitals in Serbia and Montenegro were measured using a kerma-area product (KAP) meter. The results were analysed in order to obtain dose-related parameters. Although the observed doses were within the range reported in other studies, intra-hospital and inter-hospital dose variations were significant. Mean KAP values for total examination in three hospitals were 8.4, 24.4 and 13.9 Gy cm2, respectively. Contribution from fluoroscopy was greater than from radiography. Factors contributing to the increased dose delivery were determined and the recommendations on radiographic techniques were made. Changes in radiography settings allowed dose reduction up to 48% in the radiographic part of examination, that is, up to 12% in total dose without loss of image quality. In addition, fluoroscopy time was noted as the second major contributor to the dose variations. The results demonstrated the need for standardisation of practice for barium meal examination in the country.

[Barium sulphate allergy (case report)]

Barium sulphate is a commonly used agent in the radiographic studies of the gastrointestinal tract and has been regarded as a safe contrast medium. Barium sulphate allergy is very rare. We present a case of barium sulphate allergy which occurred during an upper gastrointestinal study in a 24-year-old woman.

Serum bFGF and VEGF correlate respectively with bowel wall thickness and intramural blood flow in Crohn's disease

Serum levels of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF)--two factors known to promote tissue repair, fibroblast proliferation, and angiogenesis--were measured in Crohn's disease patients and correlated with bowel wall thickness (BWT), measured by conventional grey scale ultrasonography, and with the ileal intramural vessel flow, measured by contrast-enhanced color Doppler imaging. Serum samples were obtained from 25 patients with active Crohn's disease and 22 healthy volunteers, all sex- and age-matched. Serum bFGF and VEGF levels were measured by ELISA assay. All the patients were examined with conventional transabdominal bowel sonography. Color Doppler of the intramural enteric vessels was then performed after the intravenous injection of Levovist, a galactose-based sonographic contrast agent. In Crohn's disease patients, serum bFGF and VEGF were significantly higher compared with healthy volunteers. A positive correlation between serum bFGF and BWT and between serum VEGF and color Doppler signal intensity was found. The raised serum bFGF levels in Crohn's disease patients with intestinal strictures compared with patients with other phenotypes (fistulizing, inflammatory), together with the correlation observed between serum bFGF and BWT, suggests a possible involvement of bFGF in the process of transmural fibrogenesis in Crohn's disease. The higher levels of VEGF in those patients with increased intramural blood flow suggests that VEGF may be considered a marker of angiogenesis in this condition.

Normal anatomy and complications after gastric bypass surgery: helical CT findings

PURPOSE

To determine the usefulness and potential pitfalls of helical computed tomography (CT) for depiction of normal anatomy and diagnosis of complications after gastric bypass surgery.

MATERIALS AND METHODS

From March 1998 to July 2002, 100 abdominal and pelvic CT examinations were performed in 72 patients after gastric bypass surgery for treatment of morbid obesity. Two of four attending abdominal radiologists retrospectively assessed the CT images in consensus for normal postoperative gastrointestinal anatomy and complications such as leaks, staple line dehiscence, bowel obstruction, abscess, hepatic or splenic infarction, and hernia. CT findings were compared with clinical, surgical, and other imaging findings.

RESULTS

The gastric pouch, excluded stomach, proximal efferent loop, oversewn jejunal loop, and distal jejunojejunal anastomosis were identified in 96 (96%) of 100 studies and 69 (96%) of 72 patients, 100 (100%) of 100 studies and 72 (100%) of 72 patients, 99 (99%) of 100 studies and 71 (99%) of 72 patients, 88 (88%) of 100 studies and 61 (85%) of 72 patients, and 67 (67%) of 100 studies and 46 (64%) of 72 patients, respectively. The fundus of the excluded stomach was filled with a combination of air, fluid, and contrast material, which mimicked a loculated fluid collection in 15 (15%) of 100 studies and 13 (18%) of 72 patients. Sixty-two abnormalities, detected in 41 patients, included leak (n = 12), loculated fluid collection unrelated to leak (n = 9), markedly distended excluded stomach (n = 6), small-bowel obstruction (n = 6), gastric staple line dehiscence (n = 6), splenic infarction (n = 5), hematoma (n = 5), left hepatic lobe infarction (n = 3), and hernia related to gastric bypass (n = 10, including three internal hernias, three incisional hernias, and four nonincisional ventral hernias). Seventeen patients required a total of 21 CT-guided interventional procedures.

CONCLUSION

Helical CT is useful for identifying normal postoperative anatomy and complications after gastric bypass surgery.

Sentinel nodes of malignancies originating in the alimentary tract

The feasibility of the sentinel node concept for malignancies originating in the alimentary tract is attracting much interest among researchers in the field of gastrointestinal oncology. We have tested more than 350 such cases and obtained favorable and promising initial results. The detectability of sentinel nodes using endoscopically injected Tc-99m tin colloid for these tumors exceeded 90%. Although the false negative ratio was not so low (approximately 10%), most of these cases had an inaccurate preoperative evaluation of mural invasion and/or a technically unfavorable injection. When the indication is restricted to patients with early-stage disease, and when the radioactive colloid is properly administered, sentinel node navigation therapy would be applicable for gastrointestinal malignancies. To achieve successful sentinel node navigation surgery it is essential to accurately identify sentinel nodes, and lymphoscintigraphy is a very useful test to confirm the location of sentinel nodes preoperatively. However, image processing is required for lymphoscintigrams because the original image depicts only high activity at the injection site and faint radioactivity in the sentinel nodes. We have clearly imaged the silhouette of the body using Compton scattered photons, and have also proposed several methods to improve the contrast between the injection sites and sentinel nodes. Many sentinel nodes can be clearly visualized by subtraction of the background activity with heterogeneous distribution. The development of the portable gamma camera, enabling intraoperative imaging, also contributes to less invasive biopsy of sentinel nodes. We have obtained promising initial results using a portable imaging device with semiconductor detectors. These promising results suggest that sentinel node navigation therapy including radiotherapy will be a new therapy for early-stage gastrointestinal malignancies in the near future, with nuclear medicine contributing to the establishment of new, less invasive therapies for gastrointestinal cancer.

Drug smuggling by body packing: what radiologists should know about it

Body packing is a distinct method for smuggling drugs. What radiologists need to know is discussed in this pictorial review. Radiologists are confronted with diagnostic imaging of body packers because of two main reasons: complications of body packing and identifying drug packets within the gastrointestinal tract. The standard examination used is plain X-ray of the abdomen in an upright and a supine position. Computed tomography is occasionally used but nevertheless described as a very accurate diagnostic tool. Ultrasound and MR imaging do not play an important role in that field. Depending on the purity of the drug, three different forms of attenuation have been described: hashish is denser than stool; cocaine appears similar to stool; and heroin has a gaseous transparence. The packets are of a round to oval form, usually of a particular uniformity and rarely confused with scybala if arranged like a pearl chain; therefore, plain X-ray is the method of choice to detect drug-filled packets within the gastrointestinal tract of body packers.

[Pictorial essay: foreign body of the gastrointestinal tract in emergency radiology]

The ingestion of a foreign body is a relatively common gastrointestinal emergency that causes significant morbidity. Radiological procedures play a very important role in revealing the presence, the location and the nature of an ingested foreign body, thus enabling the best therapeutic approach. We present the radiological features of common and uncommon foreign bodies ingested or with transanal insertion, differentiated on the basis of the location in the gastrointestinal tract. Diagnostic pitfalls are also considered.