Feasibility of measuring renal blood flow by phase-contrast magnetic resonance imaging in patients with autosomal dominant polycystic kidney disease.

OBJECTIVES: Renal blood flow (RBF) has been shown to predict disease progression in autosomal dominant polycystic kidney disease (ADPKD). We investigated the feasibility and accuracy of phase-contrast RBF by MRI (RBFMRI) in ADPKD patients with a wide range of estimated glomerular filtration rate (eGFR) values. METHODS: First, we validated RBFMRI measurement using phantoms simulating renal artery hemodynamics. Thereafter, we investigated in a test-set of 21 patients intra- and inter-observer coefficient of variation of RBFMRI. After validation, we measured RBFMRI in a cohort of 91 patients and compared the variability explained by characteristics indicative for disease severity for RBFMRI and RBF measured by continuous hippuran infusion. RESULTS: The correlation in flow measurement using phantoms by phase-contrast MRI was high and fluid collection was high (CCC=0.969). Technical problems that precluded RBFMRI measurement occurred predominantly in patients with a lower eGFR (34% vs. 16%). In subjects with higher eGFRs, variability in RBF explained by disease characteristics was similar for RBFMRI compared to RBFHip, whereas in subjects with lower eGFRs, this was significantly less for RBFMRI. CONCLUSIONS: Our study shows that RBF can be measured accurately in ADPKD patients by phase-contrast, but this technique may be less feasible in subjects with a lower eGFR. KEY POINTS: Renal blood flow (RBF) can be accurately measured by phase-contrast MRI in ADPKD patients. RBF measured by phase-contrast is associated with ADPKD disease severity. RBF measurement by phase-contrast MRI may be less feasible in patients with an impaired eGFR.

Early hepatic regeneration index and completeness of regeneration at 6 months after partial hepatectomy.

BACKGROUND: The liver is known to regenerate following partial hepatectomy (PH), but little is known about the timing and completeness of regeneration relative to the resected volume. This study examined whether liver volume regeneration following PH and its completeness 6 months after surgery is related to the resected volume. METHODS: A consecutive series of patients undergoing PH were included. All patients underwent preoperative computed tomography (CT) before and 7 days after surgery. Additional scans were performed 6 months after operation. Preoperative total liver volume (TLV), resected volume, future liver remnant (FLR) and liver remnant (LR) volumes were measured on CT images by freehand drawing of regions of interest in the portal venous phase on 2-mm thick slices. Regeneration indices were calculated at 7 days (RI(early)) and 6 months (RI(total)) using the formula 100 × (LR volume-FLR volume)/FLR volume. Patients were classified into five groups based on resected volume as a percentage of TLV: 0-19, 20-39, 40-59, 60-69 and at least 70 per cent in groups 1-5 respectively. RESULTS: Ninety-one patients were enrolled. RI(early) varied from 11 to 66 per cent in groups 1-5 (P < 0·001). RI(early) did not increase linearly with increasing resection volume and a plateau was seen from group 3 and above. In contrast, RI(total) was related linearly to resected volume; values ranged from 21 to 233 per cent in groups 1-5 (P < 0·001). At 7 days, LR volume represented 97, 87, 70, 58 and 41 per cent of TLV in groups 1-5. At 6 months, respective values were 102, 99, 87, 82 and 91 per cent. CONCLUSION: Early postoperative liver volume regeneration was not related linearly to resected volume. At 6 months after surgery, RI was related linearly to resected volume, but LRs had not yet regenerated to preoperative TLV.

[What are the barriers for doctors to stop medication?] / Waarom vinden artsen het zo moeilijk om te stoppen met medicatie?

There are several dilemma's for the doctor in stopping or deminuishing medication and in diagnosing and exploring the origin of a diseaese. There can be doubt about having enough actual information about the patient, possessing knowledge about tapering and its consequences. The doctor can be vulnerable about her capacities in communication and shared decision making, in dealing with resistance or agression from the patient and with her own disappointment and feeling of failure. Also organizational barriers (such as a lack of time or continuity in care) can be involved. Team collaboration with discussion about aims and behaviour, and reflection on personal strategies and limits are necessary to guarantee quality of care.

Impact of 18-fluorodeoxyglucose positron emission tomography on computed tomography defined target volumes in radiation treatment planning of esophageal cancer: reduction in geographic misses with equal inter-observer variability: PET/CT improves esophageal target definition.

Target volume definition in modern radiotherapy is based on planning computed tomography (CT). So far, 18-fluorodeoxyglucose positron emission tomography (FDG-PET) has not been included in planning modality in volume definition of esophageal cancer. This study evaluates fusion of FDG-PET and CT in patients with esophageal cancer in terms of geographic misses and inter-observer variability in volume definition. In 28 esophageal cancer patients, gross, clinical and planning tumor volumes (GTV; CTV; PTV) were defined on planning CT by three radiation oncologists. After software-based emission tomography and computed tomography (PET/CT) fusion, tumor delineations were redefined by the same radiation-oncologists. Concordance indexes (CCI's) for CT and PET/CT based GTV, CTV and PTV were calculated for each pair of observers. Incorporation of PET/CT modified tumor delineation in 17/28 subjects (61%) in cranial and/or caudal direction. Mean concordance indexes for CT-based CTV and PTV were 72 (55-86)% and 77 (61-88)%, respectively, vs. 72 (47-99)% and 76 (54-87)% for PET/CT-based CTV and PTV. Paired analyses showed no significant difference in CCI between CT and PET/CT. Combining FDG-PET and CT may improve target volume definition with less geographic misses, but without significant effects on inter-observer variability in esophageal cancer.

Limited additional value of positron emission tomography in staging oesophageal cancer.

BACKGROUND: The detection of distant metastases in patients with oesophageal cancer may be improved with [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET), preventing unnecessary surgical explorations. The aim of this study was to assess the additional value of FDG-PET after a state-of-the-art preoperative staging protocol. METHODS: All patients in this prospective cohort study were staged with multidetector computed tomography, endoscopic ultrasonography and external ultrasonography of the neck, both combined with selective fine-needle aspiration cytology. Patients considered eligible for curative surgery after these investigations underwent FDG-PET. RESULTS: FDG-PET revealed suspicious hot spots in 30 (15.1 per cent) of 199 patients. Metastases were confirmed in eight (4.0 per cent). In six of these, distant metastases were confirmed before surgery, but exploratory surgery was necessary for histological confirmation in the other two. All eight upstaged patients had clinical stage III-IV disease before FDG-PET (6.6 per cent of 122 with stage III-IV disease). In seven patients (3.5 per cent) hot spots appeared to be synchronous neoplasms, mainly colonic polyps. However, those in the remaining 15 (7.5 per cent) were false positive, leading to unnecessary additional investigations. CONCLUSION: FDG-PET improves the selection of patients with oesophageal cancer for potentially curative surgery, especially in stages III-IV. However, the diagnostic benefit is limited after state-of-the-art staging, and so broad implementation in daily clinical practice is questionable.

Routine radiography does not have a role in the diagnostic evaluation of ambulatory adult febrile neutropenic cancer patients.

Cancer patients treated with chemotherapy are susceptible to bacterial infections. When an adult patient presents with febrile neutropenia, standard diagnostic care includes physical examination, laboratory diagnostics, chest X-ray (CXR) and sinus radiography. However, the yield of routine radiography in the diagnostic evaluation of ambulatory adult febrile neutropenic patients with normal findings at their physical examination is questionable. Two CXRs and one sinus X-ray were obtained in 109 and 106 febrile neutropenic episodes after chemotherapy in ambulatory adult patients who had no clinical signs suggesting pulmonary infection or sinusitis. We found that in only two of 109 (1.8%; 95% Confidence Interval (CI): 0.3-5.8%) febrile neutropenic episodes without clinical signs of new pulmonary disease, the CXR showed a consolidation suggesting pneumonia. In addition, in five of 88 (5.7%; 95% CI: 2.2-12.0%) febrile episodes in asymptomatic patients, sinus X-ray suggested sinusitis. In none of these seven episodes was a change of antibiotic therapy necessary. In the absence of clinical signs indicating pneumonia or sinusitis, the yield of CXR and sinus radiography in ambulatory adult cancer patients presenting with febrile neutropenia is minimal; CXR and sinus radiography should no longer be performed on a routine basis.

Pneumatosis intestinalis in patients after cadaveric kidney transplantation. Possible relationship with an active cytomegalovirus infection.

Four patients are described with pneumatosis intestinalis following cadaveric kidney transplantation, all with severe cytomegalovirus (CMV) infection. Two patients had a primary infection and 2 patients had a reactivation of CMV. One patient died because of disseminated CMV infection. Multiple inclusion bodies were found at postmortem examination in lungs and liver, and at the site of the ulcers in the gastrointestinal tract. Two patients had, concomitantly, an active, nonobstructive duodenal ulcer. In a control population of 17 patients who suffered from a duodenal ulcer post-transplant without any evidence of CMV-infection, we could not demonstrate pneumatosis intestinalis. We suggest a possible causal relationship between pneumatosis intestinalis and active CMV infection. The mechanisms that could be responsible for this relationship are discussed.

Fatal respiratory failure caused by pulmonary infiltration by pseudo-Gaucher cells.

Pseudo-Gaucher cells are reticuloendothelial cells that are found in several diseases. We report a case of pulmonary tuberculosis in which extensive pulmonary involvement with these cells resulted in fatal respiratory failure.

Pneumatosis intestinalis and active cytomegaloviral infection after lung transplantation. Groningen Lung Transplant Group.

Pneumatosis intestinalis occurred in a patient with a primary cytomegaloviral (CMV) infection with pneumonitis 6 weeks after single lung transplantation for primary pulmonary hypertension. The possible causal relationship between pneumatosis intestinalis, an uncommon disorder with an obscure pathogenesis, and active CMV infection has been observed before; however, to our knowledge, this is the first report of this combination after lung transplantation. The patient had no abdominal complaints, and after treatment of the CMV infection, the pneumatosis intestinalis resolved spontaneously. The early diagnosis of active CMV infection and the prevention of unnecessary abdominal surgery were essential in this case.

Arteriography and portal venography on routine follow-up after orthotopic liver transplantation.

RATIONALE AND OBJECTIVES: To describe the findings of routinely performed angiographic examinations in patients at discharge 2 months after orthotopic liver transplantation (OLT) and at follow-up 1 year later. METHODS: The findings of 315 angiographic examinations performed in 190 patients 2 months and 1 year after OLT were reviewed, and the changes at the anastomotic site of the hepatic artery and portal vein were analyzed. RESULTS: Routine angiography 2 months and 1 year after OLT demonstrated a normal anastomosis or low-grade stenosis in 82% and 84% of the patients (hepatic artery) and in 88% and 84% (portal vein), respectively. High-grade stenosis occurred in 9% and 5% of the patients (hepatic artery) and in 3% and 5% (portal vein). Hepatic artery occlusion and portal vein occlusion were observed in two and seven patients and in one and three patients, respectively. In 76% of patients, the anastomotic site of the hepatic artery did not change significantly. In eight patients, a normal anastomosis or a low- or medium-grade stenosis developed into high-grade stenosis or occlusion. Conversely, in nine patients, medium- or high-grade stenosis developed into a normal anastomosis or a low-grade stenosis. In all eight patients who initially had a high-grade stenosis, the hepatic artery proved to be patent at 1 year. In 98% of patients, the anastomotic site of the portal vein did not change significantly. In one patient who initially had a normal anastomosis, occlusion was found at I year. CONCLUSIONS: In most patients, routine angiography 2 months and 1 year after OLT demonstrated normal findings or a low-grade stenotic anastomosis of the hepatic artery and portal vein. Significant changes occurred mainly at the anastomotic site of the hepatic artery and could not be predicted by previous angiograms.

Pharyngoesophageal myotomy for vocal rehabilitation of laryngectomees.

Pharyngoesophageal myotomy, performed in 16 laryngectomees to improve vocal rehabilitation, proved to have some negative side effects. Although no failures of speech rehabilitation using a button were consequently found, a considerable number of button assisted esophageal speakers had a breathy voice. Also, the number of poor injection-esophageal speakers was much higher than in the group of nonmyotomized laryngectomees. A "normal" pseudoglottis could only rarely be identified by fluoroscopy in the myotomized group. A significantly lower intratracheal pressure appeared to be required for tracheo-esophageal phonation after myotomy. To improve the slightly disappointing voice rehabilitation results of the myotomized laryngectomees, a modified myotomy is proposed.

Cardiac size in the supine chestfilm.

The aim of this study was to find a normal value for the cardiac size in the supine position because such a standard is hardly known in the literature. Cardiac size in the erect and supine positions were compared in 165 patients in whom both chest radiographs were performed prior to kidney transplantation. For cardiac size as well as for cardiothoracic ratio (CTR) there is a linear relation between the measured values in the two positions which allows to determine the cardiac size in the supine position from a radiograph taken in the erect position and thus to determine whether cardiac enlargement exists in a supine chest film. A survey of 100 patients without cardiac or pulmonary pathology showed 16 patients with a heart size over 15 cm, the upper limit of normal as established over 20 years ago, which suggests that nowadays a new standard might be set. If so, the upper limit of normal CTR is 0.55 in the erect and 0.58 in the supine position. Two figures are presented to determine cardiac size and CTR in the supine position from the measured values in the erect position and vice versa.

Malrotation of the midgut: a rare complication in an adult patient.

Complications caused by a congenital anomaly of the midgut usually occur in the first 4 weeks of life; later such complications are rare. We present an adult patient with extrinsic duodenal compression caused by malrotation. The embryology, symptoms and complications in the adult and the radiological diagnosis are discussed. The literature on this subject is reviewed.

Pneumatosis intestinalis related to cytomegalo-virus infection--a new etiology?

Five patients who developed pneumatosis intestinalis in the course of a cytomegalo virus (CMV) infection after cadaveric kidney transplantation are described. Based on the fact that CMV is known to cause intestinal ulcers, we postulate a causal relationship between CMV and pneumatosis intestinalis.

Community acquired pneumonia caused by M. tuberculosis--diagnosis with CT.

A female Somalian patient presenting with a clinical picture compatible with community-acquired bilateral lobe pneumonia failed to respond to empirical anti-microbial treatment. CT of the chest revealed cavitation of the apical segment of the right lower lobe, and this feature pointed to the correct diagnosis: tuberculous pneumonia, which was eventually confirmed with cultures taken during bronchoscopy. This is the first report of the use of chest CT in the diagnosis of lower lobe tuberculosis.

Adult neuroblastoma: a report of two cases.

Neuroblastoma is an uncommon tumour arising from neural crest tissue. It is predominantly a tumour of childhood with a peak incidence in the first 3 years of life. In the USA the incidence is only about 500 paediatric cases per year. In adults it is an even more rare tumour. In 1986 Allan et al. spoke of a total of 39 reported cases of adult neuroblastoma in the world literature, with exception of some additional reports of cerebral neuroblastoma and peripheral neuro-epithelioma. Therefore neuroblastoma may cause both diagnostic and therapeutic problems. We report two recent cases of adult neuroblastoma.

Small-bowel radiography. A prospective comparative study of three techniques in 200 patients.

The authors report on a prospective study on small-bowel radiography, comparing conventional barium follow-through, single-contrast enteroclysis (Sellink's method) and double-contrast enteroclysis. Enteroclysis appeared to be superior even when the follow-through was done with frequent fluoroscopy and large amounts of contrast medium. Single and double-contrast techniques did not differ essentially in image quality. Single-contrast technique being less time-consuming is to be preferred.

Radiation enteritis: an overview.

The clinical and radiological findings in chronic radiation enteritis are described in a group of 18 patients. The patients presented with malabsorption, diarrhoea, chronic intermittent obstruction or a combination of these signs. Eventually all patients developed an ileus. The radiologist plays an important role in determining the cause of the clinical signs. The single-contrast barium infusion technique was used. In the jejunum no changes were found except bowel dilatation as a sign of an obstruction more distally. In the ileum there was evidence of submucosal thickening, adhesions and single or multiple stenoses. These changes are described in relation to the pathogenesis of chronic radiation enteritis.

Primary malignant mucosal tumours of the small bowel.

Three cases of primary malignant tumours in the small bowel are presented. The authors discuss the clinical symptoms of these patients and describe the radiological picture. Adenocarcinoma most frequently occurs in the proximal small bowel. Radiologists should be aware of the dominant site of occurrence of these tumors when performing a small bowel investigation, because lesions in the jejunum may easily be overlooked due to superposition.

[Diagnostic imaging in acute pancreatitis]. / Beeldvormende diagnostiek bij acute pancreatitis.

Acute pancreatitis is a potentially severe disease with a high morbidity and mortality rate. The natural history of acute pancreatitis is characterised by a variable clinical picture ranging from a mild and self-limiting disease to a necrotising form with various severe and potentially lethal complications. The use of early and reliable diagnostics in the detection of (infected) pancreatic necrotic tissue in the treatment of acute pancreatitis allows adequate supportive treatment to be initiated before the onset of complications, such as infection of the pancreatic necrotic tissue or multiple organ failure. Contrast-enhanced CT is currently the gold standard in the detection of necrosis. Because of some diagnostic shortcomings and disadvantages associated with this technique, such as the use of ionising radiation and the potential nephrotoxicity of the contrast agents, reliable alternative (imaging) techniques are being sought. In particular, contrast-enhanced MRI may play an increasingly important role in the future diagnostics of acute pancreatitis.