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J W Reeders

Publications and source records attributed to J W Reeders.

At least 19 recordsLinked to original sources
PubMed1995

Review of artifacts associated with transrectal ultrasound: understanding, recognition, and prevention of misinterpretation.

Artifacts are inadequate representations of the structures being imaged. Transrectal ultrasound (TRUS) used for evaluating rectal tumors has its own, unique spectrum of artifacts such as (1) pseudomasses (beam thickness: imaging of rectal folds; mirror image: reflection at an intraluminal fluid level); (2) inadequate size of the lesion (mirror image or grating lobes); (3) simulation of malignant infiltration (beam thickness, attenuation or refraction); (4) incomplete field of view (shadowing; reverberation or mirror-image); (5) confusing echo patterns (side lobe artifacts or mirror image: reflection at the balloon surface). The understanding of the physical properties of ultrasound is the basis for the recognition of these artifacts and prevention of misinterpretation. We present a review of these artifacts and their causes.

Artifacts↗
PubMed1995

Current applicability of duplex Doppler ultrasonography in pancreatic head and biliary malignancies.

In most patients with a pancreatic head carcinoma or a cholangiocarcinoma of the liver (Klatskin tumour) US is the first imaging modality. Tumour detection using US can exceed that of CT. For small tumours, endosonography or ERCP is recommended. Enlarged lymph nodes are not a major diagnostic parameter, because a reliable differentiation between reactive and malignant lymph nodes is generally not possible. Very tiny liver and peritoneal metastases are missed by the current imaging modalities including US and only detectable by laparoscopy and/or laparoscopic US. Tumour involvement of the portal venous system is an important determinant for irresectability which can often be assessed by duplex Doppler US obviating invasive or expensive imaging modalities. In pancreatic head carcinoma an abnormal pulsed Doppler signal is highly suspicious for involvement of the portal venous system. However, a normal pulsed Doppler signal does not exclude involvement at all. In Klatskin tumour, Doppler US had an accuracy of 91% compared with surgical findings in predicting portal venous involvement. In most cases of pancreatic head carcinoma or Klatskin tumour, US can assess irresectability. However, assessment of curative resectability in these tumours remains a problem.

Bile Duct Neoplasms↗
PubMed1995

Idiopathic inflammatory bowel disease: endoscopic-radiologic correlation.

PURPOSE: To assess the comparative and adjunctive diagnostic value of double-contrast barium enema examination (DCBE) and colonoscopy in cases of idiopathic inflammatory bowel disease. MATERIALS AND METHODS: Radiographic and endoscopic findings were correlated, with use of a standardized evaluation sheet, in a prospective, blinded study in 99 patients with previously well-established Crohn disease of the colon (CD [ n = 51]) or ulcerative colitis (UC [n = 48]). RESULTS: Overall, substantial to almost perfect agreement was found in more than 80% of scores with respect to the items of the standardized evaluation sheet in the colon segments depicted with both imaging modalities. Almost perfect agreement (kappa > 60%) was found for two essential diagnostic and differential diagnostic features: aphthoid erosions and fine granularity. CONCLUSION: DCBE and colonoscopy are complementary imaging modalities for optimal detection of all mucosal and structural colon lesions, except inflammatory lesions without distortion of the mucosal relief and small numbers of inflamed superficial erosions and ulcers.

Adolescent↗
PubMed1994

Contemporary radiological examination of the small bowel.

There are clinical data suggesting that the intubation method (enteroclysis) is the most accurate form of examining the small bowel. The diagnostic accuracy of small bowel enema is generally found superior to that of the tubeless method. Despite the growing interest in small bowel enema this procedure has not yet become the prevailing method in Western countries. However, due to further developments in sonde or push enteroscopy in which 300 cm of the small bowel can be visualized, it is of utmost importance to perform state of the art radiological small bowel enteroclysis investigation, otherwise the bright lights from enteroscopy will rapidly illuminate the dark corners of the small intestine, leaving no place for radiology.

Barium Sulfate↗
PubMed1994

Contemporary radiological examination of the lower gastrointestinal tract.

The morphological spectrum of colonic disease is wide. Various treatment modalities may influence the macroscopic aspect of colonic lesions and render a pathological differential diagnosis occasionally difficult or impossible. Before starting therapy in patients suspected of having colonic disease, a physician should undertake a thorough radiological and endoscopic evaluation of the extent and severity of disease activity in the large bowel (Ruderman and Farmer, 1987). DCBE and colonoscopy are complementary imaging modalities, each test has its own intrinsic advantages and merits (Lichtenstein and Rothstein, 1991). DCBE remains the cornerstone in the detection of fistulas, strictures, perforations and estimating depth of ulcerations. Colonoscopy and biopsy remain the most sensitive imaging modalities to identify mucosal involvement (Dijkstra, 1992). The main clinically relevant discrepancies between colonoscopy and DCBE consist of inflammatory lesions without distortion of the mucosal relief and inflammation in the form of small, superficial erosions and ulcers (Dijkstra, 1992).

Barium Sulfate↗
PubMed1994

Dynamic rectal examination (defecography).

Dynamic rectal examination (DRE), first described in 1952, is becoming more widely used in the dynamic evaluation of pelvic floor and anorectal motility disorders. It is a minimally invasive investigation which is well tolerated by patients and provides information about the anosphincteric, puborectal and levator muscle in addition to insight in rectal function and structure. DRE is the only investigation of anorectal function that can give detailed anatomical information such as the presence of a rectocele, an enterocele and an intussusception. DRE should be performed in a quiet environment with a minimum number of investigators present. Any technique which attempts to study the defecatory mechanism must be a compromise since the patient is aware of being studied. In order to defecate on command the radiologist must make the patient comfortable before starting the investigative procedures to avoid any possible psychological inhibition. We have not encountered any failures in this regard. The relative value of the radiological findings with respect to symptoms and complaints is insufficiently known. This has been the main incentive to design carefully and carry out a large prospective critical evaluation of various aspects of DRE in particular the correlation with objective findings and symptoms. Moreover an assessment has been made of its overall clinical utility (Wiersma, 1994). It is very likely that DRE is both investigator- and technique-dependent. To ensure that the study is as physiological as possible the contrast medium used to fill the rectum needs to be semi-solid and malleable equivalent in consistency to a normal faecal bolus. For proper anatomical studies in females vaginal opacification is mandatory. The acceptance of vaginal contrast was good. Only 4% of the female patients preferred not to have the vaginal application of contrast. The technique of DRE when performed with small bowel and vaginal opacification provides a sensitive and objective method of detecting enteroceles. A substantial number of female patients related the onset of their complaints to hysterectomy. In female patients with constipation there was a significantly higher incidence of enteroceles in patients with a hysterectomy compared to the group of females without hysterectomy. Because of these findings a series of pre- and postoperative DREs in hysterectomy patients are on their way in our institute. Unlike a rectocele which is usually most obvious during defecation, enteroceles are sometimes appreciated only with repeated straining after evacuation.(ABSTRACT TRUNCATED AT 400 WORDS)

Anal Canal↗
PubMed1993

[Radiologic diagnosis and preoperative staging of esophageal cancer].

For the treatment of esophageal carcinoma it is important to determine the length and depth of the spread. On the basis of comparable, reproducible studies the classification can be defined, which differs in Western countries from that in Japan. Conventional radiological methods such as upper-GI studies with barium sulfate and more advanced methods such as CT, echoendoscopy and MRI are discussed regarding their possibilities and limits.

Esophageal Neoplasms↗
PubMed1993

[Doppler echography for the preoperative assessment of malignant processes in the pancreas head and liver hilus].

Ultrasound is the imaging technique of choice in obstructive jaundice for demonstration of dilatation of the bile ducts, and its position and cause. In carcinoma of the pancreatic head and in hilar tumours of the liver (Klatskin) it is often possible to demonstrate their inoperability, making other imaging techniques unnecessary. Duplex-Doppler ultrasound can be highly advantageous in the evaluation of compression or invasive growth of the tumour in the mesenterico-portal venous system, making such invasive examination procedures as angiography unnecessary.

Bile Duct Neoplasms↗
PubMed1992

Perirectal lymph nodes in rectal cancer: in vitro correlation of sonographic parameters and histopathologic findings.

Preoperative staging of lymph nodes in patients with rectal cancer is essential for selecting the most appropriate therapy. To determine the discriminating value of all ultrasound parameters described in the literature, the authors obtained high-frequency sonograms of 43 lymph nodes in 21 resected rectal specimens, thereby simulating the in vivo situation. Univariate analysis revealed that inhomogeneity (P less than .0005), short axis diameter (P less than .005), and hilar reflection (P less than .01) were helpful in differentiating between metastatically involved and noninvolved lymph nodes. A prognostic trend was seen for long-axis diameter (P = .05), roundness index (P = .09), and echogenicity (P = .05). With stepwise logistic regression analysis, inhomogeneity and hilar reflection were selected as being independently discriminative. Inhomogeneity is a parameter with a high specificity; hilar reflection is particularly sensitive. No clear differentiation could be made, however, in a sizable proportion of lymph nodes (60%). The prospective use of especially these significant parameters in vivo is recommended to determine their ultimate value in preoperative staging.

Humans↗
PubMed1992

Benign fibrosing disease at the hepatic confluence mimicking Klatskin tumors.

BACKGROUND: Hilar obstructions remain a challenge with regard to diagnosis and treatment. METHODS: In the period from 1984 to 1990, 82 patients underwent resective surgery under the presumptive diagnosis of hilar cholangiocarcinoma (Klatskin tumor). The diagnosis was based on the combined appearances on direct cholangiography and ultrasonography in all cases, with the use of various other imaging modalities in some cases. RESULTS: The perioperative findings from an experienced surgical team were usually thought to be compatible with bile duct carcinoma. However, histologic examination of the resected specimens revealed benign fibrosing or localized sclerosing lesions in 11 patients (13.4%). CONCLUSIONS: The current state of diagnostic imaging fails as yet to discriminate reliably between benign and malignant hilar lesions. Whereas the immediate therapeutic consequences may be equal (resection followed by hepaticojejunostomy), the late consequences differ in a major way because benign disease has a much better prognosis. In the presence of suspicious hilar obstruction, operable lesions should not be treated by "palliative" intubational techniques and radiation therapy without a firm diagnosis of malignancy. However, overtreatment (extended liver resection, vascular reconstruction, and liver transplantation) should be avoided as well when a benign lesion has not been ruled out.

Adenoma, Bile Duct↗
PubMed1992

Pressure and X-ray recording of reflux into the thoracic stomach.

Anastomotic leakage, pulmonary aspiration and reflux-esophagitis might be induced or aggravated by the increased duodenogastric reflux observed in the thoracic stomach. In this study, the effect of respiration on the reflux-promoting pressure gradient in the intrathoracally located stomach was assessed. In nine patients pressure recording was done in the duodenum and the abdominal and thoracic part of the stomach. Intrapleural pressure was determined by recording mouth pressure during inspiratory occlusion. In addition, the course of injected contrast was examined fluoroscopically. The mean end-expiratory pressure gradient in the thoracic part of the stomach was 0.8 cm H2O, increasing up to 6.0 cm H2O and 21.3 cm H2O during normal and forced inspiration, respectively. Fluoroscopic examination showed reflux of contrast that coincided with the downward movement of the diaphragm. From this study, we conclude that reflux into the thoracic stomach is promoted by intraluminal pressure fluctuations induced by voluntary breathing. Performing a pyloroplasty or -myotomy after intrathoracic esophagogastrostomy destroys the integrity of the pyloric sphincter as a barrier to reflux, thus promoting duodenogastric reflux.

Duodenogastric Reflux↗
PubMed1991

Transrectal US in the diagnosis of localized colitis cystica profunda.

Colitis cystica profunda (CCP) mimicks rectal carcinoma, which makes distinguishing this benign lesion from the more common rectal neoplasm clinically and pathologically difficult. When transrectal ultrasound (US) was used in this case, three features of CCP were seen. There were multiple lesions, which did not penetrate beyond the submucosa. A large cystic component was seen, with a layer of uniform thickness in two of the three lesions. Non-solid contents and a lack of infiltration can be visualized at transrectal US, which helps diagnose CCP.

Colitis↗
PubMed1989

Resectional surgical procedures for carcinoma of the head of the pancreas.

Of a total series of 103 patients with preoperatively diagnosed carcinoma of the head of the pancreas (including ampullary carcinoma, carcinoma of the distal part of the common bile duct and pancreatic duct and acinar cell carcinoma), 78 underwent pancreatic resection. The remaining 25 had palliative surgical treatment, either a gastric or biliary bypass, and are not included in the present study. Three of the 78 patients who underwent pancreatic resection died, and ten patients required early reoperation. Predictive criteria could be formulated for the prognosis and outcome of the patients with carcinoma of the head of the pancreas. The most reliable index for survival time of the patients proved to be the radicality of the resection, which was directly related to the differentiation of the primary tumor. Forty-three of 48 patients who underwent radical resection are alive, with a survival time ranging from three to 49 months. Eleven of 23 patients who underwent palliative resection are alive, with a survival time ranging from two to 29 months. Of 44 patients with well or moderately differentiated adenocarcinoma who underwent radical resection, 38 are alive, with a survival time ranging from six to 41 months (mean of 29 months).

Adenocarcinoma↗
PubMed1988

Urinary tract malakoplakia with extension into the retroperitoneum with secondary gastrointestinal involvement.

A rare case of malakoplakia of the urinary tract with diffuse retroperitoneal extension is presented. Sonographically guided cytologic puncture revealed the pathologic diagnosis. The splenic flexure of the colon and the stomach appeared to be secondarily involved in the inflammatory retroperitoneal tumor. The relative role of the various imaging modalities in defining retroperitoneal extension of the disease is illustrated, with a special reference to computed tomography and endosonography. After antimicrobial treatment and left nephrectomy, partial regression of the retroperitoneal mass was documented.

Adult↗