[How to choose a radiological examination for a gastroenterological patient in 2016?] / Quelles imageries prescrire en gastroentérologie en 2016 ?

During the two last decades, medical imaging showed considerable changes in technology and in knowledge of abdominal diseases. This review illustrates the consequences of this evolution on the prescription of a radiological examination for a gastroenterological patient, in 15 selected and illustrative topics.

L'imagerie radiologique a connu des développements considérables au cours des deux dernières décennies. Ces nouveaux développements modifient la prescription raisonnée et raisonnable en imagerie médicale en pathologie gastrointestinale. Cet article de revue il lustre ces changements en 15 tableaux représentatifs de cette évolution.

Wegener's granulomatosis masquerading as a renal cancer: a case report and review of the literature.

A 32 year-old man presented with sinusitis, proteinuria, mononeuritis multiplex, very increased acute phase proteins. Anti-PR3 ANCA were detected and Wegener's granulomatosis (WG) was diagnosed. As abdominal tomodensitometry detected a tumoral process of the left kidney, a paraneoplastic vasculitis associated with a renal cancer was suspected. Biopsy of the mass showed fibrosis, inflammatory infiltrates and necrotizing granulomas. No malignant cells were detected. The outcome was favourable after administration of methylprednisolone and cyclophosphamide. Characteristics of the nine previously reported renal inflammatory pseudotumors associated with WG are discussed.

Primary Sjögren's syndrome associated with pneumatosis cystoides coli.

We report the case of a 43-year-old woman with primary Sjögren's syndrome, according to Americano-European criteria. Eighteen months after the diagnosis, the patient presented pneumatosis cystoides coli (PCC), which resolved with medical treatment consisting of diet and cisapride. Four years after this episode, the patient has not developed clinical features of another systemic inflammatory rheumatic disease and PCC has not relapsed. To the best of our knowledge, the association between primary Sjögren' syndrome and PCC has never been reported. Physiopathology and treatment of PCC are discussed.

Computerized morphonuclear characteristics and DNA content of adenocarcinoma of the pancreas, chronic pancreatitis, and normal tissues: relationship with histopathologic grading.

We report the morphonuclear characteristics of normal (13 cases), benign (ie, chronic) pancreatitis (six cases), and neoplastic (ie, ductal) adenocarcinoma (22 cases) tissues of the pancreas. This description is based on computerized cell image analysis, which permits the determination of parameters related to the morphometric (nuclear area), densitometric (nuclear DNA content), and chromatin texture features of Feulgen-stained nuclei from paraffin-embedded archival material. We observed that nuclear area discriminates between normal and benign (ie, chronic pancreatitis) as opposed to neoplastic cell nuclei. Morphonuclear parameters describing chromatin pattern characteristics made it possible to discriminate between grade I pancreatic carcinoma and normal and benign cell nuclei on the one hand, and grades I and III carcinoma on the other hand. The nuclear DNA content increased in a continuous manner from normal and benign through low-grade to high-grade neoplastic tissues of the pancreas. Combining the morphometric, densitometric, and textural parameters into one equation, we were able to calculate a score (ie, the malignancy level index) that showed a close relationship to conventional histopathologic grading. Thus, the computer-aided diagnosis of cytologic specimens from pancreatic lesions offers information of the same significance as that obtained by conventional histopathologic grading.

Transversus abdominis muscle function in humans.

We used a high-resolution ultrasound to make electrical recordings from the transversus abdominis muscle in humans. The behavior of this muscle was then compared with that of the external oblique and rectus abdominis in six normal subjects in the seated posture. During voluntary efforts such as expiration from functional residual capacity, speaking, expulsive maneuvers, and isovolume "belly-in" maneuvers, the transversus in general contracted together with the external oblique and the rectus abdominis. In contrast, during hyperoxic hypercapnia, all subjects had phasic expiratory activity in the transversus at ventilations between 10 and 18 l/min, well before activity could be recorded from either the external oblique or the rectus abdominis. Similarly, inspiratory elastic loading evoked transversus expiratory activity in all subjects but external oblique activity in only one subject and rectus abdominis activity in only two subjects. We thus conclude that in humans 1) the transversus abdominis is recruited preferentially to the superficial muscle layer of the abdominal wall during breathing and 2) the threshold for abdominal muscle recruitment during expiration is substantially lower than conventionally thought.

A pilot study for identifying at risk thyroid lesions by means of a decision tree run on clinicocytological variables.

Fine-needle aspiration biopsy (FNAB) is safe, inexpensive, minimally invasive, and highly accurate in the diagnosis of nodular diseases of the thyroid. However, FNAB does not provide a reliable benign versus malignant diagnosis for 100% of the cases analysed. It is possible to increase the accuracy of the cytological diagnosis by means of information contributed by different clinical variables. In the present study we evaluate the diagnostic value of 10 variables in addition to FNAB on a series of 218 specimens for which we obtained histological diagnoses including 37 cancers (17%). The diagnostic information contributed by these variables was analyzed by means of the Decision Tree technique, an artificial intelligence-related method which forms part of the Supervised Learning algorithms. The results show that Decision Trees enable some subpopulations of patients with uncertain FNAB results to be characterized.

Acute radiation-induced hepatic injury: evaluation by triphasic contrast enhanced helical CT.

We report a case of radiation-induced hepatic injury as a complication of localized abdominal radiotherapy for epidural spread of non-Hodgkin's lymphoma. The liver was evaluated by triphasic contrast enhanced helical CT scan. Hepatic biopsy demonstrated changes typical of veno-occlusive disease. The pattern of hepatic enhancement resulting from the radiation-induced veno-occlusive process is discussed.

Non-obstructive kidney transplant dysfunction: magnetic resonance evaluation.

The value of magnetic resonance imaging in the differential diagnosis of non-obstructive dysfunction of renal allografts was studied in a series of 58 examinations at 0.5 T. Four parameters were evaluated: the corticomedullary differentiation; the relative thickness of the cortex; the evolution, with echo number, of the relative signal intensities of kidney parenchyma and adjacent fatty tissue on images generated by a long time to repeat multiecho sequence; and the proximal vascularization. The loss of corticomedullary differentiation is the major finding in acute rejection, but it is not specific as it is also observed in chronic rejection and in the much rarer acute glomerulonephritis. Thickening of the cortex is helpful for the detection of rejected transplants with visible corticomedullary delineation (26% of the cases). Uncomplicated acute tubular necrosis appears as a normal transplant.

Case report: Renal pseudotumours mimicking tumour recurrence after partial nephrectomy.

Partial nephrectomy and tumour enucleation are increasingly accepted as an organ sparing approach for small renal cell carcinomas. Repeated computed tomography or sonography for the early detection of tumour recurrence are mandatory during the follow-up. We report two cases of renal pseudotumour mimicking a tumour recurrence: one case is related to the pseudotumoral appearance on sonography of a tumour defect filled by a fatty flap, and the other to the relative migration of an accessory spleen into the site of the cuneiform nephrectomy. The recognition of renal pseudotumours following partial nephrectomy prevents confusion with tumour recurrence on follow-up examinations.

Case report: colour Doppler demonstration of pseudoaneurysms complicating pancreatic pseudocysts.

The great morbidity and mortality associated with pseudoaneurysms complicating pancreatic pseudocysts stress the need for their early detection. The authors report the use of colour Doppler sonography in the detection of pseudoaneurysms within pancreatic pseudocysts, emphasizing not only the value of this modality in the initial diagnosis, but also its value in monitoring the success of transcatheter embolization. Colour Doppler should be used systematically in the evaluation of pancreatic pseudocysts.

Percutaneous drainage of subphrenic abscesses.

Forty subphrenic abscesses were drained percutaneously in 37 patients. These abscesses were subsequent to abdominal surgery (28 patients), biliary obstruction and/or fistula (six patients), trauma (two patients) or acute pancreatitis (one patient). The procedures were usually monitored by duplex sonography and fluoroscopy (35 out of 40 cases), with an angled subcostal approach to the subphrenic space in over 85% of the cases. Forty-three drainage catheters were inserted using the Seldinger method; 37 (86%) had a size of 12 F or more, 21 were 16 F in size. Only two out of 43 catheters were double-lumen sump drains. The clinical condition improved after insertion of the catheter in all 37 patients. Definitive successful drainage, defined as hospital discharge without complementary surgery, was achieved in 32 patients (87%), without major complications. A temporizing effect was obtained in three additional patients (8%) who underwent curative surgery for the underlying process after complete drainage of the abscess. Two patients died from multiple organ failure before their abscess healed. Considerations for successful drainage of subphrenic abscesses include a good knowledge of the subphrenic space anatomy, the use of large-bore drainage catheters and the recognition and correct management of underlying enteric, biliary or pancreatic fistulas.

Dual phase helical CT of a primary malignant fibrous histiocytoma of the right renal vein.

A case is reported of primary malignant fibrous histiocytoma of the right renal vein involving the ipsilateral kidney which showed early enhancement on dual phase helical CT. The correct diagnosis of a primary tumour of the renal vein involving the kidney was not made but in retrospect could have been achieved pre-operatively by considering several CT features.

Radiofrequency interstitial tumor ablation (RITA) is a possible new modality for treatment of renal cancer: ex vivo and in vivo experience.

Small renal tumors are increasingly diagnosed and are frequently treated by nephron-sparing surgery. Tumors can be ablated by radiofrequency (RF) energy, which allows the operator to create very localized necrotic lesions. Radiofrequency interstitial tumor ablation (RITA) has been used in human kidneys in an ex vivo experiment to assess the necrotic lesions produced in a model close to physiologic conditions and then in three patients with localized renal cancer prior to radical nephrectomy. In the ex vivo model, four freshly removed kidneys were treated. Bipolar RF energy was delivered by a generator connected to two needles introduced parallel to each other into the renal parenchyma. A thermocouple was inserted between the two active electrodes. The renal artery at physiologic conditions was maintained at a constant temperature of perfusion of 37 degrees C by a computer-assisted Hot-line monitor. Two lesions were produced in each pole of each kidney including the cortex and the medulla. In an initial human study focusing on safety, feasibility, and pathology, three patients were treated by RITA with bipolar and monopolar energy. One patient with a peripheral 2-cm upper-pole tumor was treated percutaneously under ultrasound guidance with local anesthesia only 1 week prior to surgery. The other patients, with 3- and 5-cm tumors, were treated during surgery under general anesthesia just before nephrectomy. Ex vivo, the maximum temperature at the active needles ranged from 84 degrees C to 130 degrees C with 10 to 14 W applied during 10 to 14 minutes. Lesions were on average 2.2 x 3 x 2.5 cm.3 Microscopic examination showed stromal edema with intensive pyknosis. No damage was seen to adjacent untreated tissue. In the in vivo procedure, tolerance of RTA as an anesthesia-free procedure was excellent. The size of the observed lesions was comparable to the forecast size depending on the needle deployment. No side effects were noted, and no adjacent structures were affected by the RF ablation. These preliminary studies demonstrate the ability of RITA to produce localized extensive necrosis in kidney parenchyma and tumors safely under local anesthesia. Further studies could evaluate this new minimally invasive treatment in small kidney tumors considered for nephron-sparing surgery.

Retrospective analysis of 29 patients surgically treated for hepatocellular adenoma or focal nodular hyperplasia.

BACKGROUND/AIMS: Hepatocellular adenoma resection and focal nodular hyperplasia supervision are widely recognized as the best management when these benign liver tumors are diagnosed. Differential diagnosis is thus mandatory. METHODOLOGY: Twenty-nine patients with a presumed benign liver tumor were retrospectively analyzed. RESULTS: Histopathological analysis of these resected liver tumors demonstrated hepatocellular adenoma in 16 patients and focal nodular hyperplasia in 13. One hepatocellular carcinoma was disclosed into a hepatocellular adenoma and 2 hepatocellular adenoma showed foci of liver-cell dysplasia. Seven patients with hepatocellular adenoma (43%) had evidence of intratumoral hemorrhage, among which 3 patients were admitted with intraperitoneal tumoral rupture. Computed tomography, performed in 26 patients, was the most reliable examination to characterize these presumed benign liver tumors. Magnetic resonance imaging concerned only 5 patients but 3 hepatocellular adenoma and 1 focal nodular hyperplasia were diagnosed. The indications of focal nodular hyperplasia surgical resection were chronic pain (4 pts), hepatocellular adenoma diagnosis (4 pts), undeterminate liver mass (2 pts), a liver mass of unknown origin in patients with a neoplastic history (3 pts). A diagnosis of focal nodular hyperplasia assumed by the imaging work-up was always histologically confirmed. All the patients underwent hepatic resection with no mortality. CONCLUSIONS: This report underlines the risk of hemorrhage or malignant transformation of hepatocellular adenoma that justifies a safety surgical resection. An imaging work-up in favor of focal nodular hyperplasia allows radiological observation.

Intussusception in adults--report of 3 cases.

Intussusception in the adult is rare. The cases reported here illustrate the usual clinical development of the condition: incomplete, subacute, or chronic subobstruction. Intussusception is usually associated with a localized lesion, mostly a small bowel benign tumor, and a colonic malignant tumor. Diagnosis is effected using barium enema, ultrasonography, or CT scanning. Treatment of intussusception requires surgical intervention.

Local ablative treatments for liver metastases: the current situation.

Surgical resection is the optimal treatment for liver metastases. However, due to their multifocality and/or insufficient remnant liver volume, the majority of liver metastases are unresectable. For this reason, several local ablative techniques have been developed, aiming to produce selective tumour destruction and thus increase the rate of patients amenable to curative-intent treatments. Among these techniques, cryoablation and radiofrequency ablation only have proven to have a curative potential, while transarterial chemoembolization and alcohol injection should be considered as palliative options only. The local recurrences after cryoablation and radiofrequency are equivalent, inferior to 10%, highly dependent of selection criteria. In contrast, morbidity is significantly increased after cryoablation, leading most of the teams to prefer the radiofrequency approach. Two major limitations for radiofrequency are, first, the risk to provoke heat biliary lesion in case of metastases located proximally to hilar plate, and second, the risk of insufficient ablation due to a cooling effect in case of metastases near to major vessels. Keeping in mind these limitations, selective use of radiofrequency may offer a significant benefit by allowing complete tumour clearance in patients with unresectable liver metastases.

[Cyst of the seminal vesicle. Images on ultrasonography, x-ray computed tomography and magnetic resonance. Apropos of a case]. / Kyste de la vésicule séminale. Aspect en échotomographie, tomodensitométrie et résonance magnétique. A propos d'un cas.

A case of seminal vesicle cyst is reported. Magnetic resonance (M.R.) appearance of the seminal vesicle cyst is described first. A brief review of the literature for seminal vesicle cysts is made. New imaging modalities (ultrasound, C.T. scan an M.R.) are illustrated, their role is discussed.

[Magnetic resonance imaging, with surface coil, of a transplanted kidney]. / Imagerie en résonance magnétique avec antenne de surface du rein transplanté.

MR appearance of the kidney transplant is evaluated on a series of 80 examinations performed on a supraconductive unit operating at 0.5 T. Normal function kidneys displayed a clearly delineated corticomedullary differentiation (CMD); the ratio between the thickness of cortex and medulla didn't exceed 0.6. The same appearance was observed in non complicated acute tubular necrosis. Complete loss of CMD was the major finding in acute rejection (74% of the cases), but it was not specific as it was also observed in chronic rejection and in acute glomerulonephritis. Cortex thickening was helpful for the detection of rejected transplants with visible CMD. The sensitivity of MR in the detection of acute rejection was 94%. Specificity of MR findings for acute rejection depended on the transplant age: it varied from 100% for examinations performed during the first 3 months after transplantation, to less than 50% for examinations of the second year.

[Prostatic pathology imaged by magnetic resonance. 58 cases]. / Pathologie prostatique en résonance magnétique. 58 observations.

Forty-eight patients with prostatic disease (benign prostatic hyperplasia (B.P.H.), carcinoma, cysts, myoma and prostatitis) and 10 normal volunteers underwent magnetic resonance imaging (M.R.I.) of the prostate. The prostatic parenchyma was best evaluated by a T2-weighted spin-echo pulse sequence. The prostate in patients with B.P.H. often had a homogeneous or more rarely a nodular appearance on T2-weighted images. In most cases, a peripheral dark rim is observed. All prostate in patients with carcinoma had an heterogeneous appearance on T2-weighted images. While most of the prostatic carcinomas appeared hypo-intense relative to adjacent prostatic parenchyma, some of the neoplasms had a high or mixed-high and low signal. The myoma showed a low-signal nodule like carcinoma. The cyst appears as a liquid tumor. The prostatitis had an homogeneous bright signal. With the used methodology, MRI can differentiate prostatic diseases in many cases. Nevertheless the technique has to be optimized to improve its accuracy.

[MRI of the prostate. Calculated imaging. Preliminary experience: 28 cases]. / IRM de la prostate. Imagerie calculée. Expérience préliminaire: 28 observations.

The majority of studies with MR imaging in prostate disease are based on a semiology obtained using images weighted in T1 and T2. A study was carried out to evaluate effects of images calculated in T1 and T2 obtained at 0.5 T. This preliminary study concerns 28 prostate examinations with spin-echo acquisition and inversion-recuperation parameters, and provided images calculated in T1, weighted and calculated in T2. Images allowed detection and characterization of prostate lesions. However, although calculated images accentuate discrimination of the method, the weighted images conserve their place because of their improved spatial resolution.