Two-year audit of computed tomographic colonography in a teaching hospital: are we meeting the standard?

OBJECTIVE

We aimed to determine whether adopting the published recommendations has led to successful implementation of computed tomographic colonography (CTC) in a teaching hospital setting outside the context of a clinical trial.

METHOD

An audit of all the CTC examinations between April 2005 and June 2007 was conducted to determine the following: adequacy of bowel preparation, CTC indications and findings (compared with available colonoscopy), complications and experience of reporting radiologist.

RESULTS

The most common indications for the 111 CTC patients reviewed included exclusion of synchronous colonic tumours, incomplete colonoscopy and altered bowel habit. Only 16% of ascending colon/caecal segments was clear of faecal or fluid contamination. The rectum and sigmoid colon were free of contamination in 78% and 74% of cases respectively. Appropriately trained radiologists reported 91% of studies. Thirty-two percent of studies were normal. The most common positive findings were diverticular disease or a rectal tumour. Sensitivity, specificity and positive predictive value were 89%, 94% and 90% respectively (all polyps) with a sensitivity of 98.5% for lesions > 5 mm in size. Twenty-five percent of patients had extra colonic abnormalities. There were no recorded complications.

CONCLUSION

Our CTC practice is within accepted published guidelines. Bowel preparation is suboptimal in a significant proportion of cases and faecal tagging is being implemented.

The radiological manifestations of intramuscular haemangiomas in adults: magnetic resonance imaging, computed tomography and ultrasound appearances

OBJECTIVE

Intramuscular haemangiomas in adults may appear similar to soft tissue sarcomas on imaging. This study evaluates the imaging characteristics of intramuscular haemangiomas on magnetic resonance imaging (MRI), computed tomography (CT) and ultrasound.

SUBJECTS AND METHODS

Retrospective review of medical records, imaging and pathology details of 34 patients presenting with intramuscular haemangiomas was performed. Age of patient, size, site of lesion and type of imaging was recorded. Lesions were evaluated for calcification, presence of fat, outline, texture, vascularity, enhancement and involvement of local structures.

RESULTS

There were 12 male and 22 female patients aged between 9 years and 90 years (mean 39 years). Twenty-two lesions involved muscles of the extremities and 12 involved muscles of the trunk. Mean duration of the lesions was long: 59.3 months (range 3-240 months), with an average size of 7.5 cm (1.5-15 cm). Imaging comprised 27 MR studies, seven CT scans, 19 ultrasounds, and eight plain films. All lesions were well defined, lobulated and heterogeneous. None showed local invasion. On MRI and CT, 93-100% showed the presence of fat and 100% showed vascular channels and enhancement on MRI, CT and ultrasound. Phleboliths were seen on four plain films (50%) and on the corresponding MR images. On MRI, 70% of lesions had mildly hyperintense signal on T1-weighted sequences and 96% had hyperintense signal on T2-weighted sequences (relative to skeletal muscle). Histopathology confirmed diagnosis in all cases, showing the presence of fat, medium/large vessels and skeletal muscle.

CONCLUSION

Intramuscular haemangiomas have characteristic appearances on MRI, CT and ultrasound. Long history, presence of fat, calcification and internal vessels should alert the radiologist to this diagnosis prior to biopsy.

Computed tomography findings in fibrosing mediastinitis

AIM

To describe the CT features of fibrosing mediastinitis.

MATERIALS AND METHODS

The clinical notes, histology, and CT images from 12 patients with fibrosing mediastinitis were reviewed. Clinical data regarding the presentation and suspected aetiology were correlated with location of mediastinal disease, calcification, effect on mediastinal structures, and additional pulmonary findings on computed tomography (CT).

RESULTS

The mean age was 40.5 years, with seven female and five male patients. The most common presenting symptom was shortness of breath. Fibrosing mediastinitis diffusely infiltrated the mediastinum in five patients and was localized in seven. Calcification was present in two cases. Eleven of 12 cases had narrowing of mediastinal structures, including five with pulmonary artery narrowing, five with superior vena cava obstruction, four with bronchial narrowing, three with tracheal narrowing, and one with narrowing of the pulmonary vein. The disease was considered idiopathic in seven cases with a demonstrable aetiology in five cases. Eight out of 12 patients had additional pulmonary findings, including all patients with a known aetiology.

CONCLUSIONS

In the present series of patients, fibrosing mediastinitis more commonly presented as a localized mediastinal mass than as diffuse mediastinal disease, with the anterior mediastinal compartment most frequently involved. Most cases were idiopathic compared with the majority of previous cases at this institution being ascribed to tuberculosis. There is a high incidence of concomitant pulmonary findings, in particular when an identifiable aetiology is present. Obstruction of vital structures frequently gives rise to complications.

Eisenmenger syndrome and idiopathic pulmonary arterial hypertension: do parenchymal lung changes reflect aetiology?

AIM

To document the pulmonary vascular changes on thin-section computed tomography (CT) in patients with Eisenmenger syndrome and idiopathic pulmonary arterial hypertension, and to determine whether there is any correlation with pulmonary arterial pressures or the aetiology of pulmonary hypertension.

MATERIAL AND METHODS

From the National Pulmonary Hypertension Database, we identified eight patients with idiopathic pulmonary arterial hypertension and 20 patients with Eisenmenger syndrome (secondary to a ventriculoseptal defect) who had also undergone contrast-enhanced thin-section CT. CT studies were reviewed for the presence of centrilobular nodules, mosaicism, neovascularity, and bronchial artery hypertrophy. Haemodynamic data were also reviewed.

RESULTS

Centrilobular nodules, mosaicism, and neovascularity were seen in both patient groups (p>0.05). A significantly higher number of enlarged bronchial arteries were seen in patients with Eisenmenger syndrome. There was no correlation with pulmonary arterial pressures.

CONCLUSION

Patients with idiopathic pulmonary arterial hypertension and Eisenmenger syndrome demonstrated similar pulmonary vascular changes on CT. These changes did not predict the underlying cause of pulmonary hypertension or its severity.

Imaging features of isolated unilateral pulmonary artery agenesis presenting in adulthood: a review of four cases

AIM

To highlight the variation in clinical manifestations, imaging and management of four cases of unilateral pulmonary artery agenesis presenting in adulthood.

METHOD

Four patients with unilateral pulmonary artery agenesis were referred to our institution between 1995 and 2005. They underwent a series of investigations, including chest radiography, echocardiography, ventilation perfusion scintigraphy, angiography, computed tomography (CT) and magnetic resonance imaging (MRI).

RESULTS

Two of the four patients had absence of the right main pulmonary artery, whilst the remaining two patients had absence of the left main pulmonary artery. One patient showed a restrictive defect on pulmonary function tests. Two patients who had ventilation perfusion scintigraphy showed absent perfusion and reduced ventilation on the affected side. Angiography (where performed), CT and MRI confirmed the anatomy and the presence of multiple collaterals. Bronchiectasis was demonstrated on CT in two patients, with one also demonstrating a mosaic attenuation pattern. One patient had an incidental lung tumour on the side of the agenesis, which was diagnosed as a chondroid hamartoma on histology. Three of the four patients eventually underwent resection of the affected lung.

CONCLUSION

Isolated unilateral pulmonary artery agenesis has a non-specific presentation. Awareness of this condition can lead to earlier diagnosis, with cross-sectional imaging making an important contribution.

Quality of life in patients with chronic anal fissure

OBJECTIVE

Little is known about the quality of life in patients with the distressing symptoms of chronic anal fissure. This was a prospective study assessing the physical and mental health of fissure patients before and after topical treatment.

PATIENTS AND METHODS

New patients attending the fissure clinic were recruited prospectively into the study over a 2-month period. On first appointment, patients were given 2 questionnaires to complete: the Short-Form 36 Health Survey (SF-36) and a general questionnaire recording patients' demographic details, previous treatment, site and duration of fissure and symptoms on a visual analogue scale (VAS). Following an 8-week course of topical treatment, patients repeated the SF-36 and symptoms were again recorded on a VAS. Healing of fissure was noted.

RESULTS

Fifty-four patients entered the study, of which 39 returned for follow-up; 16 male, 23 female; mean age 38.6 years (range 17-80 years). Median duration of fissure was 6 months (3 months - 10 years). Higher VAS ratings for fissure pain were associated with worse scores for all aspects of health-related quality of life, including mental health (P < 0.001), bodily pain (P < 0.001), vitality (P < 0.006) and social functioning (P < 0.001). Compared to age and gender matched norms for the SF-36, fissure patients had more bodily pain (P < 0.001, Wilcoxon) and poorer health perceptions (P < 0.02, Wilcoxon). Gender did not affect any of the SF-36 subscales. However, females did report significantly more bleeding (P = 0.05). On follow-up, healing was complete in 27 patients (69%). Symptoms of pain, bleeding and irritation were all significantly reduced in this group. Repeating the SF-36 showed an improvement in bodily pain, role-physical functioning and vitality (P < 0.05).

CONCLUSION

Successful nonsurgical treatment of chronic anal fissure leads to symptomatic improvement and beneficially affects health-related quality of life.

L-arginine-induced relaxation of the internal anal sphincter is not mediated by nitric oxide

BACKGROUND

Topical application of L-arginine, the precursor of nitric oxide, reduces resting anal pressure without significant side-effects and may therefore be of benefit in the treatment of anal fissure. This in vitro study investigated the effect of L-arginine on sheep and human isolated internal anal sphincter (IAS) to ascertain the role played by nitric oxide and guanosine 3',5'-cyclic monophosphate.

METHODS

Strips of sheep and human IAS were mounted in isolated organ baths. The effects on myogenic tone of increasing concentrations of L-arginine, D-arginine and other amino acids were evaluated.

RESULTS

L-Arginine, D-arginine and other basic amino acids (L-lysine and L-ornithine) all caused a concentration-dependent reduction in myogenic tone. L-Arginine was the most effective and produced a mean(s.e.m.) maximal reduction in myogenic tone of 78.2(7.1) and 40.2(9.3) per cent in sheep and human tissue respectively. These responses were not affected by N(G)-nitro-L-arginine methyl ester, a nitric oxide synthase inhibitor, or 1H-[1,2,4]oxadiazolo[4,3-a]-quinoxalin-1-one, an inhibitor of soluble guanylyl cyclase. Changes in pH per se were unable to explain the relaxation fully, but an equiosmolar sodium chloride solution produced a concentration-response relationship similar to that of L-arginine.

CONCLUSION

The ability of L-arginine to reduce myogenic tone is independent of nitric oxide. This effect may be partially pH dependent but the osmolality of the solution appears to be a major factor. Hyperosmolar solutions might be worthy of further investigation as agents that affect anal tone.

The role of topical diltiazem in the treatment of chronic anal fissures that have failed glyceryl trinitrate therapy

OBJECTIVE

The treatment of anal fissures has evolved over the last 5 years with the development of topical treatments aimed at reducing sphincter hypertonia. This is thought to improve anal mucosal blood flow and promote healing of the fissure. This study reports the use of topical diltiazem in patients with chronic anal fissures that have failed previous treatment with topical 0.2% glyceryl trinitrate (GTN).

PATIENTS AND METHODS

Forty-seven patients with chronic anal fissure who had previously failed at least one course of topical GTN were recruited prospectively from a single centre. Patients were instructed to apply 2 cm (approximately 0.7 g) of 2% diltiazem cream to the anal verge twice daily for eight weeks. Symptoms of pain, bleeding and itching were recorded on a linear analogue score prior to starting the cream and then repeated at 2 weekly intervals. Patients were asked to report side-effects throughout the study period. Healing of the fissure was assessed after 8 weeks of treatment.

RESULTS

Forty-six patients completed treatment; of these, 22 had healed fissures (48%). Ten of the 24 patients with persistent fissures were symptomatically improved and wished no further treatment. Of the 14 patients who remained symptomatic, one was given a repeat course of 0.2% glyceryl trinitrate with subsequent healing of the fissure, 10 were recruited into an ongoing study involving injections of botulinum toxin into the internal anal sphincter and three were referred for surgery.

CONCLUSION

This study shows that topical 2% diltiazem is an effective and safe treatment for chronic anal fissure in patients who have failed topical 0.2% GTN. The need for sphincterotomy can be avoided in up to 70% of cases.

Topical L-arginine gel lowers resting anal pressure: possible treatment for anal fissure

PURPOSE

Exogenous nitric oxide donors, such as glyceryl trinitrate, have been used as treatment for anal fissures; however, headaches develop in 60 percent of patients. Nitric oxide produced from the cellular metabolism of L-arginine mediates relaxation of the internal anal sphincter. This study investigated whether topical L-arginine gel reduces maximum anal resting pressure in volunteers.

METHOD

In a two-center study, volunteers received a single topical dose of L-arginine or placebo (Aquagel ). Anal manometry was performed for two hours after application of 400 mg of L-arginine gel or placebo gel to the anal verge in 25 volunteers. Side effects were recorded after single application and also after repeated dosing for three days.

RESULTS

L-Arginine reduced maximum anal resting pressure by 46 percent from a median of 65 cm of water to a minimal value of 35 cm of water ( P< 0.001, Wilcoxon's signed-rank test). The difference between L-arginine and placebo using repeated-measures testing was significant at P< 0.005. No side effects occurred with either gel; in particular, no episodes of headache were recorded.

CONCLUSION

Topical L-arginine gel significantly lowers maximum anal resting pressure; its onset of action is rapid, and duration is at least two hours ( P< 0.01). L-arginine may have therapeutic potential, but further evaluation is needed before it can be used as a possible alternative treatment for chronic anal fissure.

Requirement for B cell linker protein (BLNK) in B cell development

Linker proteins function as molecular scaffolds to localize enzymes with substrates. In B cells, B cell linker protein (BLNK) links the B cell receptor (BCR)-activated Syk kinase to the phosphoinositide and mitogen-activated kinase pathways. To examine the in vivo role of BLNK, mice deficient in BLNK were generated. B cell development in BLNK-/- mice was blocked at the transition from B220+CD43+ progenitor B to B220+CD43- precursor B cells. Only a small percentage of immunoglobulin M++ (IgM++), but not mature IgMloIgDhi, B cells were detected in the periphery. Hence, BLNK is an essential component of BCR signaling pathways and is required to promote B cell development.

Antibodies raised by gastrimmune inhibit the spontaneous metastasis of a human colorectal tumour, AP5LV

Both precursor forms of gastrin and mature amidated gastrin peptides can enhance proliferation of colorectal tumours and may regulate growth in an autocrine manner. The purpose of this study was to evaluate the effect of neutralization of precursor and amidated gastrin on primary and secondary in vivo growth of a human colorectal tumour. The human colorectal cell line, AP5LV, when injected into the muscle layer of the abdominal wall of severe combined immunodeficient (SCID) mice, grows as a well-vascularized primary tumour and metastasis to the lung. AP5LV expressed the precursor gastrin forms; progastrin and glycine-extended gastrin and gastrin/CCKB receptors, as assessed by immunocytochemistry. Gastrimmune is a gastrin immunogen in which the amino terminus of the gastrin-17 molecule is linked to diphtheria toxoid and induces antibodies which neutralise the amidated and glycine-extended forms of gastrin-17. Rabbit antiserum, raised against Gastrimmune, was administered intravenously into SCID mice bearing AP5LV tumours. Control animals were treated with antiserum raised against diphtheria toxoid only. Antibodies raised against Gastrimmune significantly limited the growth of primary AP5LV tumours, as assessed by median cross-sectional area (controls = 244 mm2; antibody-treated = 179 mm2; P = 0.033). In addition Gastrimmune-induced antiserum limited the growth of lung metastasis as assessed by nodule number (controls = 3.5; antibody-treated = 1.0; P = 0.0001) and nodule cross-sectional as assessed by image analysis (controls = 11.9 mm2; antibody-treated = 3.75 mm2; P = 0.0064). In conclusion in vivo neutralization of gastrin forms, which may potentially be fueling growth by an autocrine pathway, inhibited both primary growth and, to a greater degree, lung metastasis of a human colorectal tumour cell line. Immunization against tumour-associated gastrin forms may provide an effective therapy for advanced colorectal cancer.

Gastric carcinoid expresses the gastrin autocrine pathway

BACKGROUND

In gastric adenocarcinoma the gastrin autocrine-paracrine pathway is activated. As enterochromaffin-like (ECL) cells originate from the same stem as epithelial cells, the aim of this study was to determine if the gastrin autocrine pathway is present in gastric carcinoid.

METHODS

Samples from ten patients with gastric carcinoid were assessed by immunocytochemistry using primary antibodies directed against gastrin precursors and the gastrin/cholecystokinin B receptor and detected using the avidin-biotin immunoperoxidase system.

RESULTS

A high level of expression of precursor and mature gastrin peptides, together with the gastrin receptor, was seen in all carcinoids screened.

CONCLUSION

In common with the glandular epithelium of the stomach the gastrin gene is activated during the neoplastic process in ECL cells. This finding may explain why some carcinoids do not regress after surgical procedures that lower serum gastrin. Antigastrin agents may be a useful treatment for carcinoid either in their own right or as an adjunct to surgery.

Recurrent corneal infections in a patient with the acquired immunodeficiency syndrome

A 29-year-old female intravenous drug abuser infected with the human immunodeficiency virus suffered recurrent, bilateral corneal infections over an 11-month period. Multiple infectious organisms were responsible, including capnocytophaga species, Candida albicans, Staphylococcus aureus, coagulase-negative staphylococcus, and a-streptococcus. One eye was eviscerated because of corneal perforation and loss of vision; the second eye has maintained good vision. Predisposing factors usually associated with corneal infections were absent. Treatment was complicated by extremely poor patient compliance, ongoing intravenous drug abuse, and concurrent multiple extraocular medical problems.

Flow cytometric studies of ploidy and proliferative indices in the Yorkshire trial of adjuvant progestogen treatment of endometrial cancer

OBJECTIVE

To estimate whether flow cytometric indices provide independent measures of prognosis or predict response to prophylactic progestogens in endometrial cancer.

DESIGN

Endometrial tumour specimens were retrieved and analysed by flow cytometry from 257 women who had been randomly allocated in a previous trial to receive prophylactic progestogen in addition to conventional therapy for endometrial carcinoma.

SETTING

Fourteen district and two teaching hospitals in West Yorkshire.

SUBJECTS

Women developing primary endometrial cancer between 1975 and 1983.

MAIN OUTCOME MEASURES

Tumour ploidy status and proliferative indices and the relation of these to tumour stage and grade, to prognosis and to response to progestogens.

RESULTS

Ploidy status and proliferative indices were related to tumour stage, grade and patient survival but were not independent predictors of survival. They did not predict patients who would respond to progestogens although there was a nonsignificant trend towards patients with diploid tumours surviving longer after progestogen treatment.

CONCLUSIONS

Flow cytometry adds little to established prognostic indicators for endometrial cancer.

Direct pituitary inhibition of prolactin secretion by dopamine and noradrenaline in sheep

The effects of dopamine, noradrenaline and 3,4-dihydroxyphenylacetic acid (DOPAC) on the release of prolactin were examined in ovariectomized ewes. Infusion of dopamine (0.5 or 1 microgram/kg per min for 2 h i.v.) reduced plasma prolactin concentrations in a dose-dependent manner, whereas DOPAC (5 or 10 micrograms/kg per min for 2 h i.v.) had no effect. In a further series of experiments, ovariectomized hypothalamopituitary disconnected ewes were given dopamine or noradrenaline (each at 0.5 or 1 microgram/kg per min for 2 h i.v.), and both amines reduced mean plasma concentrations of prolactin with similar potency in a dose-dependent manner. These effects were blocked by treatment with pimozide and prazosin respectively. During the infusion of dopamine, the peripheral plasma concentrations of DOPAC and 3,4-dihydroxyphenylethyleneglycol (DHPG) were increased (DOPAC, 22 +/- 7 (S.E.M.) to 131 +/- 11 nmol/l; DHPG, 2.9 +/- 0.3 to 6.4 +/- 0.2 nmol/l), but plasma concentrations of dopamine and noradrenaline did not change. Finally, administration of domperidone, a specific dopamine receptor antagonist that does not cross the blood-brain barrier, resulted in a sustained increase in plasma prolactin concentrations in ovariectomized ewes. We conclude that the secretion of prolactin from the pituitary gland is under dual inhibitory regulation by both dopamine and noradrenaline in the sheep.

The posterior pituitary regulates prolactin, but not adrenocorticotropin or gonadotropin, secretion in the sheep

The aim of this study was to determine the role of the posterior pituitary gland in the control of PRL, LH, FSH, and ACTH secretion in sheep. Posterior pituitary function was removed in ovariectomized ewes by electrical lesioning of the hypothalamo-neurohypophysial tract immediately posterior to the stalk-median eminence (LESION); controls were subjected to sham surgery (SHAM). LESION caused a 2-fold increase in plasma PRL concentrations on days 1-3 after surgery. Thereafter, concentrations gradually declined until they were similar to those in SHAM ewes. There was no change in plasma concentrations of LH, FSH, or ACTH after LESION. Plasma PRL responses to insulin in SHAM ewes were completely abolished, and the plasma PRL response to chlorpromazine was reduced to almost half by LESION. In contrast, audiovisual stress (barking dog) and serotonin challenge caused an immediate release of PRL in both LESION and SHAM ewes, with the amplitude of the responses indistinguishable between groups. LESION had no effect on the plasma ACTH responses to audiovisual stress, insulin, or serotonin. We conclude that the posterior pituitary gland is involved in the regulation of PRL under some circumstances, but not of LH, FSH, or ACTH secretion in the sheep. Accordingly, changes in PRL release after hypothalamopituitary disconnection in this species may reflect a loss of posterior lobe function rather than the removal of hypothalamic inputs. In addition, the PRL response to insulin is dependent on a functional posterior pituitary gland, whereas responses to audiovisual stress and serotonin appear to rely on inputs to the pituitary gland via the median eminence and the long hypothalamo-hypophysial portal blood vessels.