Highly aggressive neuroendocrine neoplasm of the ascending colon: a wolf in sheep's clothing.

Neuroendocrine neoplasms represent a broad group of uncommon tumours, comprising neuroendocrine tumours, mixed neuroendocrine non-endocrine neoplasms and neuroendocrine carcinomas. While most neuroendocrine neoplasms are well differentiated and exhibit indolent disease biology with excellent treatment response, neuroendocrine carcinomas represent a rare subtype with much more aggressive tumour behaviour, minimal response to adjuvant therapy and extremely poor prognosis. Herein, we report the case of a 47-year-old man who presented with a phlegmonous ascending colonic mass and associated calcified ileocolic lymphadenopathy. He underwent emergent right hemicolectomy, which diagnosed a T4aN2b neuroendocrine carcinoma. Within a week the patient displayed rapidly progressive locoregional nodal disease and he succumbed to disease within 5 weeks. We discuss the significance of calcified abdominal lymphadenopathy on computed tomography scans of the abdomen and review the literature surrounding this rare and highly fatal malignancy.

Effect of commercial cleansers on skin barrier permeability.

BACKGROUND: Addition of hydrophobically modified polymers (HMPs) to cleansers can reduce the negative impact of surfactant-based cleansers. In this study, the effects of a cleanser containing HMPs, a gentle lotion cleanser (GLC), water, and 1% sodium lauryl sulfate (SLS) on barrier permeability, were evaluated in vitro in pig skin and in vivo in humans. METHODS: Skin stratum corneum (SC) barrier function was quantitated by imaging fluorescence intensity of the sulforhodamine B (SRB) in a pig skin model system using 2-photon and conventional fluorescence confocal microscopy. Solutions containing SRB were applied to pig skin in Franz diffusion cells over a period of 2 h. Penetration of SRB into the skin was monitored from 2 µm to 38 µm. In vivo surfactant/cleanser penetration in human skin was determined using tape stripping. RESULTS: After 2 h, water, 1% SLS, and GLC, significantly increased SRB intensity at all depths measured. SRB intensity was reduced in the HMP-cleanser group compared with other groups at each depth. In vivo, the presence of HMP reduced SLS penetration as measured by tape stripping. CONCLUSION: The cleanser containing HMP prevented changes in SC permeability and surfactant penetration, indicating a protective effect on skin barrier properties.

Treatment of chronic anal fissure with topical glyceryl trinitrate.

PURPOSE: There has been an emerging trend to treat chronic anal fissures by pharmacologic means. In particular, by the topical application of glyceryl trinitrate. However, such treatment has failed to gain wide acceptance within our local surgical community. The aim of this study was to evaluate the efficacy and patient acceptance of topical glyceryl trinitrate in the management of chronic anal fissures. METHODS: A retrospective review was conducted on a consecutive series of 31 patients who were diagnosed as having a chronic anal fissures and were managed by the topical application of 0.2 percent glyceryl trinitrate to the perianal region twice a day. All patients were commenced on a high-fiber diet, and they were reviewed every two weeks until healed or until surgery was required. Patients were subsequently contacted by a mailed questionnaire to determine compliance with therapy, resolution of symptoms, recurrence of symptoms after cessation of therapy, and side effects. RESULTS: Of 31 patients, 27 completed the questionnaire. Only 67 percent (18/27) of patients complied with the treatment as prescribed, and just 56 percent (15/27) achieved complete resolution of their symptoms after three to ten weeks of therapy. Recurrence of symptoms developed in 27 percent (4/15) of these patients after a median follow-up of six months. Side effects were reported in 78 percent (21/27) of patients, and in ten percent (2/21) they were so severe that the patients ceased therapy. CONCLUSION: In this study the treatment of chronic anal fissures with topical glyceryl trinitrate appeared less efficacious than previously reported. In addition, the study highlighted problems with patient compliance, healing rates, and side effects that are associated with this modality therapy.

Use of computed tomography scanning before and after sitting in an emergency department.

RATIONALE AND OBJECTIVES: Before a computed tomography (CT) scanner was installed in the emergency department, this hospital had no dedicated CT scanner for patients in the emergency department, and transporting these patients to the CT scanners in the radiology department took approximately 8-10 min each way. We sought to determine whether the presence of a CT scanner within the emergency department would lead to an increase in the number of emergent cranial CT examinations and a decrease in the diagnostic yield of these examinations. METHODS: More than 8,000 records of cranial CT examinations were reviewed for the 12 months before and the 12 months after the installation of the CT scanner in the emergency department. A positive case was defined as one that showed acute abnormality such as ischemia, hemorrhage, edema, or mass effect. RESULTS: Our results show a 30.1% increase in the number of CT scans of the head ordered by physicians in the emergency department after the installation of a CT scanner (p < .0001). This is compared with the background 1.8% increase in the total number of emergency department visits. However, in both periods, 12% of the total number of head scans done were positive. CONCLUSION: The convenience of having a CT scanner in the emergency department leads to greater use of CT examinations. However, the increase in the number of emergent CT studies is justified because the number of positive CT examinations increases proportionately.

Percutaneous revascularization of complex iliac artery stenoses and occlusions with use of Wallstents: three-year experience.

PURPOSE: To assess the outcome of percutaneous placement of Wallstents for treatment of hemodynamically significant diffuse stenoses (> 3 cm in length), chronic occlusions, failed angioplasty procedures, and flow-limiting dissection in the iliac arteries. MATERIALS AND METHODS: Lesions in 94 iliac limbs were treated in 66 patients. Indications for stent placement included claudication in 49 limbs and limb-threatening ischemia in 45. Forty-two limbs were treated for diffuse disease, 39 for chronic occlusion, nine for failed angioplasty, and four for flow-limiting dissection. RESULTS: Technical success was achieved in 86 of 94 limbs (91%), with major complications in 9% of patients. One death occurred within 30 days (not procedure-related). Ankle-brachial indexes improved from 0.51 +/- 0.24 to 0.76 +/- 0.22 (P < .001). Eighty-five percent demonstrated improvement under Rutherford criteria. Follow-up was obtained up to 38 months (mean, 14 months +/- 8). Cumulative primary patency rates were 78% at 1 year and 53% at 2 and 3 years (standard error 10%). Secondary patency rates were 86% at 1 year and 82% up to 32 months (standard error > 10% after 32 months). No significant decrease in mean ankle-brachial index was observed during follow up. No difference in primary patency was observed based on lesion type, symptom severity, lesion location, or runoff status. The limb salvage rate for patients with limb-threatening ischemia was 98% at a mean follow-up of 14 months +/- 7. CONCLUSIONS: Technical success and complication rates for percutaneous iliac artery revascularization with use of Wallstents are favorable, symptoms improved in the majority of patients, and excellent secondary patency can be achieved. With use of Wallstents, most patients with iliac artery insufficiency as a result of long-segment disease or chronic occlusions can be treated percutaneously.

Incidence of deep vein thrombosis after arthroscopic knee surgery: a prospective study.

Deep vein thrombosis (DVT) with subsequent pulmonary emboli (PE) is the most life-threatening complication of knee arthroscopy. Although the incidence of clinically diagnosed DVT after arthroscopy is low, clinical examination is less sensitive and specific than other diagnostic modalities for the detection of venous clot. This study used compression ultrasound to prospectively evaluate patients before and after arthroscopic surgery for the presence of DVT. Preoperatively, patients were screened for DVT risk factors. Eighty-five patients completed the study. Three asymptomatic "silent" DVTs were identified, for an incidence of 3.5%. There was no statistically significant difference between those with and without risk factors for the development of DVT.

Neural ensemble coding in inferior temporal cortex.

1. Isolated, single-neuron extracellular potentials were recorded sequentially in area TE of the inferior temporal cortex (IT) of two macaque monkeys (n = 58 and n = 41 neurons). Data were obtained while the animals were performing a paired-associate task. The task utilized five stimuli and eight stimulus pairings (4 correct and 4 incorrect). Data were evaluated as average spike rate during experimental epochs of 100 or 400 ms. Single-unit and population characteristics were measured using a form of linear discriminant analysis and information theoretic measures. To evaluate the significance of covariance on population code measures, additional data consisting of simultaneous recordings from < or = 8 isolated neurons (n = 37) were obtained from a third macaque monkey that was passively viewing visual stimuli. 2. On average, 43% of IT neurons were activated by any of the stimuli used (60% if those inhibited also are included). Yet the neurons were rather unique in the relative magnitude of their responses to each stimulus in the test set. These results suggest that information may be represented in IT by the pattern of activity across neurons and that the representation is not sparsely coded. It is further suggested that the representation scheme may have similarities to DNA or computer codes wherein a coding element is not a local parametric descriptor. This is a departure from the V1 representation, which appears to be both local and parametric. It is also different from theories of IT representation that suggest a constructive basis set or "alphabet". From this view, determination of stimulus discrimination capacity in IT should be evaluated by measures of population activity patterns. 3. Evaluation of small groups of simultaneously recorded neurons obtained during a fixation task suggests that little information about visual stimuli is conveyed by covariance of activity in IT when a 100-ms time scale is used as in this study. This finding is consistent with a prior report, by Gochin et al., which used a 1-ms time scale and failed to find neural activity coherence or oscillations dependent on stimuli. 4. Population-stimulus-discrimination capacity measures were influenced by the number of neurons and to some extent the number and type of stimuli. 5. Information conveyed by individual neurons (mutual information) averaged 0.26 bits. The distribution of information values was unimodal and is therefore more consistent with a distributed than a local coding scheme.(ABSTRACT TRUNCATED AT 400 WORDS)

Is bilateral lower extremity compression sonography useful and cost-effective in the evaluation of suspected pulmonary embolism?

OBJECTIVE: Because deep venous thrombosis is clinically linked with pulmonary embolism and often treated similarly, we sought to assess the usefulness of obtaining bilateral lower extremity compression sonograms when findings on ventilation-perfusion lung scans indicate a low or indeterminate probability of pulmonary embolism. Demonstration of deep venous thrombosis would provide a rationale for treating both pulmonary embolism and deep venous thrombosis. MATERIALS AND METHODS: Two hundred twenty-three consecutive patients with suspected pulmonary embolism had ventilation-perfusion lung scans and concurrent bilateral lower extremity compression sonograms; 34 also had pulmonary arteriography. RESULTS: In 75 cases, the results of ventilation-perfusion lung scanning indicated an indeterminate probability of pulmonary embolism. Evidence of thrombosis was seen on sonograms in 11 of these 75. In the remaining 64, 17 underwent pulmonary arteriography and four (24%) had pulmonary embolism. Findings on lung scans indicated a low probability of pulmonary embolism in 70 of 223 patients. Evidence of thrombosis was seen on sonograms in 11 of these 70. Five of the remaining 59 underwent pulmonary arteriography and one (20%) had pulmonary embolism. According to the 1993 Medicare Fee Schedule, if all 145 patients whose lung scans were nondiagnostic had sonography and only those with normal sonograms had pulmonary arteriography, the professional and hospital charges would be $359,552. If all 145 had pulmonary arteriography without sonography, the charges would be $395,031. CONCLUSION: If ventilation-perfusion lung scans indicate a low or an indeterminate probability of pulmonary embolism and bilateral lower extremity compression sonography is performed, only those patients with normal sonographic findings would need further study. Thus, 15% (22/145) of patients could be spared pulmonary arteriography, and the estimated savings in cost would be 9%.

Use of preprocedural tests by interventional radiologists.

A direct survey was taken of 1,238 members of the Society of Cardiovascular and Interventional Radiology (SCVIR) concerning the routine use of 14 tests (most frequently, prothrombin and partial thromboplastin times, complete blood cell counts, and blood urea nitrogen and serum creatinine levels) performed before 10 invasive percutaneous procedures (peripheral angiography, neuroangiography, transluminal angioplasty, thrombolysis, percutaneous needle biopsy, abscess drainage, percutaneous nephrostomy, biliary drainage, myelography, and venography). The survey was undertaken to determine the current practices and appropriateness of current routine use of preprocedural tests. The response rate was 34%, representing a cumulative annual volume of 322,208 cases. The practice of performing routine preprocedural tests is common among interventional radiologists. Data provided by this survey suggest that use of these tests is excessive. Adherence to suggested proposals derived from previously reported experience would result in an annual estimated savings of $20.0-$34.9 million (extrapolated for all procedures performed by SCVIR members in 1989).

Arteriosclerosis obliterans in a rabbit model.

RATIONALE AND OBJECTIVES: The authors induced atherosclerotic occlusions in a rabbit model, using and comparing different experimental methods. METHODS: Lesions were induced in 40 femoral arteries in 20 rabbits. Four combinations of lesion induction methods were used: 1) drying of the endothelium with carbon dioxide gas; 2) gas-drying of the artery plus mechanical injury; 3) gas-drying plus induced thrombosis of the treated segment using thrombin; and 4) gas-drying, mechanical injury, and induced thrombosis. All rabbits were fed a high-fat, high-cholesterol diet for 1 to 2 months after lesion induction. RESULTS: Seventeen rabbits were available for follow-up. Sixty-eight percent (13 of 19) of femoral arteries treated with thrombin-induced thrombosis demonstrated atherosclerotic occlusions, compared with 27% of those that did not receive this treatment (4 of 15; P < .01). CONCLUSIONS: Thrombin-induced thrombotic occlusion of a segment of artery which has been de-endothelialized, followed by a high-fat, high cholesterol diet, results in a higher yield of experimental occlusive atherosclerosis in rabbits than is achievable by other methods.

Venous ultrasonography.

Compression ultrasonography supplemented by pulsed and color Doppler imaging is the diagnostic modality of choice for evaluating lower extremity deep vein thrombosis in symptomatic and asymptomatic high-risk patients. Furthermore, this technique frequently can characterize the clot as occlusive or nonocclusive or acute or chronic and can define the extent of disease. In patients without thrombosis, this modality can suggest an alternative diagnosis in 12% of patients.