Endoanal MRI of the anal sphincter complex: correlation with cross-sectional anatomy and histology

The purpose of this study was to correlate the in vivo endoanal MRI findings of the anal sphincter with the cross-sectional anatomy and histology. Fourteen patients with rectal tumours were examined with a rigid endoanal MR coil before undergoing abdominoperineal resection. In addition, 12 cadavers were used to obtain cross-sectional anatomical sections. The images were correlated with the histology and anatomy of the resected rectal specimens as well as with the cross-sectional anatomical sections of the 12 cadavers. The findings in 8 patients, 11 rectal preparations, and 10 cadavers, could be compared. In these cases, there was an excellent correlation between endoanal MRI and the cross-sectional cadaver anatomy and histology. With endoanal MRI, all muscle layers of the anal canal wall, comprising the internal anal sphincter, longitudinal muscle, the external anal sphincter and the puborectalis muscle were clearly visible. The levator ani muscle and ligamentous attachments were also well demonstrated. The perianal anatomical spaces, containing multiple septae, were clearly visible. In conclusion, endoanal MRI is excellent for visualising the anal sphincter complex and the findings show a good correlation with the cross-sectional anatomy and histology.

Endoanal magnetic resonance imaging versus endosonography

INTRODUCTION

A major limitation of anal endosonography is the poor inherent contrast, which is the cause of the cumbersome identification of the longitudinal layer and external sphincter. Endoanal MRI was introduced to overcome this problem. The normal anatomy, perianal fistulas and sphincter defects as visualized by endoanal MRI as compared to endoanal sonography are discussed.

MATERIAL AND METHODS

Endoanal sonography was performed with an 18-mm diameter 7-MHz endoanal probe. For endoanal MRI a 19-mm diameter endoanal receiver coil was used at 0.5 T. Volunteers and patients with anal fistula or fecal incontinence were examined with both techniques.

RESULTS

Endoanal MRI demonstrates the internal sphincter but also the longitudinal layer and external sphincter in great detail. The external sphincter is the lower outer part of the sphincter, while the puborectal muscle is the upper outer part of the sphincter which is connected to the levator ani muscle. External sphincter defects are more often identified and better delineated with MRI. Endoanal MRI is superior in the identification and classification of perianal fistulas.

CONCLUSION

Endoanal MRI is an important new diagnostic tool in anal imaging. The anal sphincter anatomy and pathology are excellently demonstrated. Endoanal MRI is superior to endoanal sonography, especially in the identification of external sphincter defects and in the classification of tracks.

Fistula in ano: endoanal sonography versus endoanal MR imaging in classification

PURPOSE

To assess agreement between endoanal sonography, endoanal magnetic resonance (MR) imaging, and surgery in depiction and classification of fistula in ano.

MATERIALS AND METHODS

Twenty-eight consecutive patients with nonspecific, cryptoglandular fistula in ano were studied. The fistulas were classified with endoanal sonography, endoanal MR imaging, and surgery. Agreement between the modalities was also evaluated.

RESULTS

Classification of fistulas was possible in 17 of 28 patients (61%) with sonography, in 25 of 28 (89%) with MR imaging, and in 26 of 28 (93%) with surgery. Concordance between endoanal sonography and MR imaging occurred in 46% of the cases (kappa = 0.27, poor agreement); between sonography and surgery in 36% (kappa = 0.09, no agreement); and between MR imaging and surgery in 64% (kappa = 0.43, moderate agreement).

CONCLUSION

Endoanal MR imaging more accurately allows depiction and classification of fistula in ano than endoanal sonography.

Imaging of the anorectal region

Imaging of anorectal region has drastically changed during the last decade. Transrectal ultrasound and transrectal MRI can be used for staging the rectal tumours. Endoanal sonography can be applied for the classification of perianal fistulae and identification of anal sphincter defects in patients with faecal incontinence. Due to the limitations of endoanal sonography, endoanal MRI was introduced to assess the pathology related to the anal sphincter complex. Endoanal MRI seems superior to endoanal sonography. This paper describes the new developments of the imaging techniques and presents new insights in anatomy and pathology of the anorectum.

Anal sphincter complex: endoanal MR imaging of normal anatomy

PURPOSE

To determine the normal anatomy of the anal sphincter complex on magnetic resonance (MR) images.

MATERIALS AND METHODS

Ten healthy volunteers (four men, six women; age range, 21-26 years) underwent MR imaging with an endoanal coil.

RESULTS

The lower part of the anal canal contained the internal sphincter, the longitudinal muscle layer, and the external sphincter; the upper part comprised the internal sphincter, the longitudinal layer, and the puborectal muscle. At the upper end, the puborectal muscle was attached to the levator ani muscle. Anteriorly, the external sphincter was connected to the urogenital diaphragm; posteriorly, it was attached to the coccyx with the anococcygeal ligament. All perianal spaces were visible. The morphology of the anterior part of the external sphincter, different in men and women, was well displayed.

CONCLUSION

Depiction of the anal sphincter complex on MR images is excellent.

Invasive group B streptococcal disease in children beyond early infancy

There is little information available on invasive group B Streptococcus (GBS) infection in pediatric patients older than 3 months of age. Review of infection control records at LeBonheur Children's Medical Center from January 1, 1986, to June 30, 1993, identified 143 patients with a positive GBS culture from normally sterile body fluid. Medical records of 18 (13%) patients > 3 months old with their first GBS infection were reviewed. Age range was 15 weeks to 18 years (median age, 13 months). Ten were black and 11 were girls. Five infants had a history of premature birth and 2 infants were infected with human immunodeficiency virus. The serotype distribution of 12 available GBS isolates was 4 type III, 2 each type V and Ia and 1 each type Ia/c, Ib/c, II and II/c. Bacteremia without a focus (9 patients) was the most common clinical manifestation. All 4 type III isolates were associated with bacteremia. One infant with human immunodeficiency virus infection had sepsis and bullous desquamation; a toxin-producing type V strain was isolated from her blood. Two adolescents with ventriculoperitoneal shunts had meningitis, including one whose cerebrospinal fluid also grew a type V strain. Other clinical manifestations were septic arthritis, endocarditis (Ia, II/c), central venous catheter (Ia/c) and ventriculostomy infections.

Safety, feasibility and long term follow-up of a non-thoracotomy defibrillation system in patients with inducible sustained ventricular tachycardia/fibrillation

A non-thoracotomy lead system CPI-ENDOTAK, a transvenous lead used alone or combined with a subcutaneous patch (SQ-P), was evaluated as an alternative to epicardial patches/electrodes in patients at high risk for sudden cardiac death undergoing implantable cardioverter-defibrillator (ICD) surgery. Fifty nine patients, 62 +/- 11.4 years with CAD (83.0%) cardiomyopathy (11.9%) other (5.1%), mean ejection fraction 31.8 +/- 14%, with inducible sustained VT/VF underwent testing of either lead alone or lead/SQ-P. Four configurations of NTL were tested. Fifty one patients had NTL implanted (lead alone = 60.8% and lead/SQ-P = 39.2%). Eight patients required non-NTL approaches, due to high DFT (7) or anatomic anomaly (1). DFT's were 19.1J (lead alone) and 20.8J (lead/SQ-P). Acute complications: pulmonary embolism 1, lead dislodgement 3, sensing malfunction 1. [table: see text]

CONCLUSION

A NTL system using either a single transvenous lead alone or combined with SQ-P can be implanted successfully in high risk patients with a low incidence of acute complications. Non-arrhythmic survival is lowest in patients receiving defibrillation shocks. Arrhythmic survival is high in all patients.

Case report: solitary ischaemic small bowel stenosis

A case of a solitary short ischaemic stenosis of the small bowel is presented and the literature reviewed. An ischaemic segmental stenosis of the small bowel is a rare lesion, but can lead to acute or subacute obstructive symptoms. A well conducted small bowel enteroclysis is the diagnostic modality of choice in such a case, which may require surgical resection after the diagnosis is made.

Ultrasonography is accurate enough for the diagnosis of intussusception

For more than 10 years the authors have been using ultrasonography to confirm clinically suspected intussusception without performing a contrast enema. The aim of this study is to review this diagnostic policy. Between 1980 and 1989, 163 children who, on clinical examination and plain abdominal radiographs were suspected of having intussusception, underwent ultrasonography to confirm the diagnosis. In 33 children, ultrasonography did not show intussusception; of the remaining 130 children, intussusception was diagnosed in 128. In two children in whom intussusception was noted subsequently, the diagnosis was not established on ultrasound. Thus, ultrasonography had a sensitivity of 98.5% and a specificity of 100% in the diagnosis of intussusception. It is a quick, simple, noninvasive method to diagnose intussusception, with high accuracy. The role of contrast enema is limited to therapeutic application.

Plain film diagnosis in intussusception

In early childhood intussusception a characteristic gas pattern is often visible on plain radiographs which can be used for diagnosis. To test this hypothesis, radiographs of 163 children with intussusception, and as many controls, were reviewed. By using multivariable analysis, it appeared that five out of seven parameters (reduced amount of gas in the jejunum; lateralization of the ileum; indiscernible caecum; reduced amount of feces in the colon; and visibility of the intussusceptum) had discriminatory value. For each parameter a weighting (in points) was derived and the patients were classified: the higher the score the more likely that an intussusception was present. A sensitivity of 90% and a specificity of 90% were obtained.

Early emergent coronary bypass after failed angioplasty

Emergency CABG for failed coronary angioplasty was required in 3.3 percent of 1,625 consecutive patients undergoing angioplasties. Twenty-six percent of the patients died in the perioperative period. Efforts must be concentrated on identifying PTCA failure prior to cardiogenic shock.

Early emergent coronary bypass after failed angioplasty

Emergency CABG for failed coronary angioplasty was required in 3.3 percent of 1,625 consecutive patients undergoing angioplasties. Twenty-six percent of the patients died in the perioperative period. Efforts must be concentrated on identifying PTCA failure prior to cardiogenic shock.

Radiographic evidence of bronchopulmonary dysplasia in high-risk congenital diaphragmatic hernia survivors

Congenital diaphragmatic hernia is a congenital malformation associated with pulmonary hypoplasia. It often leads to respiratory failure, requiring artificial ventilation with high inflation pressures and high percentages of oxygen. We evaluated radiographic evidence of bronchopulmonary dysplasia (BPD) in survivors, who presented with respiratory distress within 6 hours after birth, by a radiographic scoring system measuring the severity of BPD by the Toce score and the degree of pulmonary hypoplasia by the Touloukian score. Fifteen of 45 survivors (33 percent) had clinical and radiological lung disease resembling BPD. As a group they had significantly higher Touloukian and Toce scores than survivors without BPD. Morbidity expressed as the duration of artificial ventilation, supplemental oxygen, and hospital stay was much higher in the BPD group. The hypoplastic lung in infants with congenital diaphragmatic hernia appears to be as susceptible to barotrauma and pulmonary oxygen toxicity as the lungs of prematurely born infants. To what extent BPD occurring in congenital diaphragmatic hernia survivors might influence the future development of lung function is not yet known.

Estrous cyclicity in nonlactating and lactating Holsteins and Jerseys during a Pakistani summer

Data from 36 cows were used in a 2 x 2 factorial arrangement to determine the effects of breed and lactation status on estrous cyclicity during a Pakistani summer (June through October). Cows were selected from a herd of Holsteins and Jerseys imported from the United States 5 yr earlier. Ambient temperatures were highest in June and declined in the ensuing months with the onset of the rainy season. Relative humidity increased in July and August and them remained stable until the end of the study. Although early morning rectal temperatures gradually declined from June through October, late afternoon rectal temperatures were highest in August. Average early morning rectal temperatures were higher in Holsteins than in Jerseys (38.5 vs. 38.3 degrees C). Even though all cows were cyclic throughout the study, as indicated by patterns of progesterone secretion, observed expression of estrus was low (36.8%) and unaffected by breed or lactation status. Average serum progesterone concentrations were lower (2.4 vs. 3.1 ng/ml), and cortisol concentrations were higher (4.1 vs. 3.9 ng/ml), in Holsteins than in Jerseys. Breed by lactation status interactions were significant for lengths of the luteal phase and estrous cycle. Lengths for lactating Holsteins were longer than those of other groups.

Comparison of immediate seeding of endothelial cells with culture lining of small diameter ePTFE carotid interposition grafts

This study is the first to compare chronic healing characteristics of immediately seeded grafts with those of grafts lined by autogenous venous endothelial cells in tissue culture prior to implantation. Ten mongrel dogs had a segment of external jugular vein excised for enzymatic harvest of endothelial cells. After approximately 21 days growth in tissue culture, 4 X 10(6) cells/ml were inoculated into a 6-cm length of 4 mm i.d. ePTFE for formation of a confluent lining in culture media. The remaining external jugular vein had its endothelial cells enzymatically harvested for immediate seeding of an identical length of preclotted ePTFE. Both grafts were implanted end-to-end in the carotid position and excised after 30 days. In 6 of the 10 dogs, grafts were patent bilaterally; all others were occluded. Planimetric measurements on patent grafts with immediate seeding showed a thrombus-free surface area of 56 +/- 39% compared to 86 +/- 15% for culture-lined grafts (P = 0.046). Endothelial coverage was 70 +/- 24% for immediately seeded grafts and 29 +/- 21% for culture-lined grafts (P = 0.016). We conclude that immediate seeding and culture lining of autogenous endothelial cells in small diameter ePTFE grafts produce equivalent short-term patency. While culture-lined grafts have an initially less thrombogenic luminal surface, subsequent development of a confluent endothelial lining is slower than that with an immediate seeding preparation, and thus would appear to offer no significant clinical benefit, especially in light of the complexity culture lining adds to the procedure.

Plain film diagnosis in meconium plug syndrome, meconium ileus and neonatal Hirschsprung's disease. A scoring system

Abdominal plain films of 133 neonates, with 82 cases of meconium plug syndrome (MPS), 27 cases of meconium ileus (MI) and 24 cases of neonatal Hirschsprung's disease (HD), were reviewed to assess the value of such radiographs for diagnosis. The radiographs were examined according to a list of 11 parameters. By using multivariate discriminant analysis, it appeared that 4 parameters i.e. dilatation of bowel loops, varying loop calibre, fluid levels and colonic gas were most important in discriminating among the three disorders. For each parameter the weight (in points) was derived. To classify patients, three group-scores had to be calculated: the group-score with the largest value indicated the most likely disorder. So in 99%, 88% and 63% of MPS, HD and MI, respectively, an accurate diagnosis could be predicted. The overall diagnostic accuracy was 89%. Such a diagnosis can be a sound basis for further investigation.

Effect of SMS201-995 (a long-acting somatostatin analog) on bile-induced acute hemorrhagic pancreatitis in the dog

Recent reports claim a beneficial role for SMS201-995 (SMS) in pancreatitis. To study the effects of SMS in a canine pancreatitis model, four groups of eight dogs each were subjected to laparotomy; and after cannulation of the dorsal pancreatic duct, a mixture of bile and trypsin was infused to induce pancreatitis. Group I constituted the control group and received no SMS. Group II received SMS intravenously at 5 micrograms/hr beginning 1 hour before the induction of pancreatitis. Group III and Group IV received SMS at the same dose starting at 2 hours and 6 hours, respectively, after the induction of pancreatitis. Infusions were maintained until 24 hours after the induction of pancreatitis. Leukocyte counts, serum lipase and amylase levels were obtained preoperatively and at 24 hours. All dogs were killed at 24 hours and autopsies performed. At autopsy, severity of pancreatitis was graded, based on survival, the presence or absence of pancreatic edema, hemorrhage, and necrosis, as well as the presence and severity of bloody ascites. Only on a dog (Group III) died before the 24-hour period. When SMS was used before the induction of pancreatitis, the pancreatitis seen was less severe (Group I vs Group II, P = .022). No effects were found when using SMS after the induction of pancreatitis (Group III or Group IV vs Group I). The serum lipase, amylase, and leukocyte counts changed significantly in all the dogs (P less than .001) with the onset of pancreatitis, but this difference was not significant between groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary angioplasty versus coronary bypass. Three-year follow-up of a matched series of 250 patients

Two hundred fifty consecutive patients treated for one or two vessel coronary artery disease with either balloon angioplasty or surgical bypass were monitored for 3 years in a study designed to determine the comparative long-term effectiveness of each treatment. The 125 patients having angioplasty were matched with the 125 patients having bypass, so that both groups had a similar number of patients with single or double vessel disease. The two groups did not significantly differ in age, male:female ratio, New York Heart Association class, or risk factors. The ejection fraction was 54 +/- 11 in the angioplasty group and 49 +/- 12 mmHg in the surgical patients (p = 0.0031). Angioplasty was deemed initially successful in 88% (110/125), unsuccessful in 10% (12/125), and in 2% (3/125) the lesion could not be crossed. Emergency bypass was performed in 10% (12/125). Four of the 125 angioplasty patients (3%) died within 30 days. Coronary artery bypass grafting was successfully performed on the matched set of surgical patients with 99% (124/125) discharged well. There was one (1%, 1/125) surgical death. The average hospital stay per patient was 4.8 +/- 3.1 days for angioplasty and 12.1 +/- 4.2 days for bypass grafting (p = 0.0000). Three-year postprocedure follow-up was obtained on 96% (236) of the 245 patients discharged alive. A second angioplasty was required in 18%, and 11 angioplasty patients subsequently required surgical bypass. Overall, 19% (23/121) of the angioplasty patients ultimately required bypass. Four late deaths occurred in the angioplasty group, which brought the early and late mortality rates to 7% (8/121). There were two late surgical deaths, which brought the combined surgical mortality to 2.5% (3/120), p = 0.1263. Patient evaluation reveals that 63% (76/121) of the angioplasty group are alive and in New York Heart Association class I or II 3 years after one or two angioplasty procedures. This figure compares with 92% (110/120) of surgical patients alive and in the same two New York Heart Association classes (p = 0.0000).

Emergency operation after failed angioplasty

A group of patients with failed angioplasty who then required emergency coronary bypass was compared with a historically matched group of patients who had had elective bypass grafting. The two groups were well matched in age, sex, ejection fraction, and New York Heart Association classification and in the incidence of diabetes and hypertension. Significant differences were found in the prevalence of mortality (12% versus 1.5%), hemorrhage (28% versus 13%), cardiac tamponade (10.5% versus 1.5%), myocardial infarction (28% versus 9%), and length of hospital stay (15.3 days versus 13.4 days). Cardiogenic shock carries the worst prognosis; four of the five patients with this condition died. Because emergency operation after failed angioplasty carries with it significant postoperative morbidity and mortality, this procedure cannot be considered equivalent to elective coronary bypass grafting.