Differential diagnosis between a granuloma and radicular cyst: effectiveness of magnetic resonance imaging

AIM

To investigate the diagnostic reliability and accuracy of magnetic resonance imaging (MRI) to differentiate periapical lesions of endodontic origin and to compare the results with histopathological information.

METHODOLOGY

The radiolucent periapical jaw lesions of 34 patients, which were surgically enucleated, were investigated by two radiologists using MRI, based on the same six criteria, to categorize the lesions as granulomas, radicular cysts or others. After apicoectomies, two oral pathologists (blinded to the radiologist's diagnoses) analysed all specimens by referring to seven specific parameters and diagnosed the specimens as granulomas, radicular cysts or other conditions. The inter-rater agreements between the radiologists and pathologists in terms of MRI and histological diagnoses, respectively, along with the discriminant power of the adopted criteria and the accuracy of the MRI assessments compared with the histopathological results, were calculated. Cohen's kappa test was adopted to examine inter-rater agreement between the two radiologists and two pathologists. Guttman's lambda coefficient (λ₆ ) was used to evaluate the internal consistency of the items used for the differential diagnosis by radiologists. The accuracy resulted from a receiver operator characteristic (ROC) analysis.

RESULTS

A strong inter-rater reliability was observed between the two radiologists (k-statistic = 0.86, P = 0.0001) and the two pathologists (k-statistic = 0.88, P = 0.0001). The internal consistency of the diagnostic items was 0.605 for cysts and 0.771 for granulomas. The accuracy (true positives plus true negatives) of the radiologists was greater than that of the pathologists based on analysis (area under the curve = 0.87 and 0.91, respectively).

CONCLUSIONS

The reliability and accuracy of MRI were high and comparable to histopathological reliability, highlighting the usefulness of this noninvasive technique as a pre-treatment diagnostic method for periapical endodontic lesions.

Comparison of transvaginal sonography and double-contrast barium enema for diagnosing deep infiltrating endometriosis of the posterior compartment

OBJECTIVES

To compare the diagnostic accuracy of transvaginal sonography (TVS) and double-contrast barium enema (DCBE) in the preoperative detection of deep infiltrating endometriosis (DIE) of the posterior compartment.

METHODS

This was a prospective study of 69 consecutive patients with results of pelvic examination or symptoms suggestive of DIE of the posterior compartment. TVS and DCBE were performed before surgery by two groups of physicians specialized in endometriosis, each blinded to the results of the other technique. Imaging data were compared with histopathologic analysis of the resected specimen (gold standard). Sensitivity, specificity, positive and negative predictive values and test accuracies were calculated for both imaging modalities.

RESULTS

Sixty seven of the 69 women had a nodule of DIE confirmed at laparoscopy and histopathologic examination. TVS diagnosed DIE in 57 (85%) of these patients, while DCBE revealed the presence of the lesion in 24 (36%) women. For the diagnosis of posterior DIE, TVS and DCBE had, respectively, a sensitivity of 85% and 36%, specificity of 100% and 100%, positive predictive value of 100% and 100%, negative predictive value of 17% and 4% and accuracy of 85.5% and 38%. In patients with pure bowel DIE the sensitivity was 91% and 43%, specificity was 100% and 100%, positive predictive value was 100% and 100%, negative predictive value was 29% and 6% and accuracy was 91% and 45%, respectively.

CONCLUSIONS

TVS has a much higher sensitivity than does DCBE in detecting the presence of posterior DIE and should thus be regarded as the imaging modality of choice when there is clinical suspicion of the disease.

Cluster of serogroup C meningococcal disease associated with attendance at a party

BACKGROUND

An unexplained increase has occurred in the incidence of invasive meningococcal disease in adolescents and young adults.

METHODS

We investigated a cluster of serogroup C meningococcal disease in 3 previously healthy young adults who had attended a party in Maryland. Molecular subtyping was done on the isolates from the 3 cluster cases and 4 control isolates by pulsed-field gel electrophoresis (PFGE). The only common exposure was attendance at the party, where a large number of people reportedly smoked tobacco or marijuana and/or drank alcohol.

RESULTS

The PFGE analysis of the 3 case isolates showed identical molecular subtypes.

CONCLUSION

This investigation strongly suggests that transmission of the cluster strain occurred at the party. Transmission may have occurred in part as a result of the recently described risk factors of binge drinking and smoking. Taken together, these findings suggest that some of the recent increase in invasive meningococcal disease may be due to modifiable risk factors.

Wernicke's encephalopathy in a child: case report and MR findings

We report a child affected by Wernicke's encephalopathy (WE), which was unsuspected clinically. MRI suggested the correct diagnosis and prompted appropriate thiamine replacement. WE is a difficult condition to recognise, especially in children, and MRI may be useful in the diagnosis of the disease.

Male caregivers' use of formal support

The purpose of this study was to explore male caregivers' perceptions of formal support. The men were caregivers of adults with cognitive impairment. The study involved secondary analysis of interview data on perceptions of support that had not been previously analyzed from the perspective of formal support. Techniques of data analysis used in grounded theory were applied to 62 guided interactive interviews conducted with 24 male caregivers during a period of 18 months. The men experienced a process of making concessions for care in the following four sequential stages: resisting, giving in, opening the door, and making the match. Personal barriers deterred the caregivers from seeking help, and once the caregivers engaged formal help the influence of characteristics of the health care system and individual staff members had both enabling and disabling effects. For caregivers whose use of formal support involved admitting their relative to a long-term care facility, the phase of making the match was followed by redesigning their caregiver role.

Meckel's diverticulum: imaging diagnosis

Despite the availability and wide use of modern imaging techniques, the diagnosis of Meckel's diverticulum is difficult. The signs and symptoms vary from none to those of an acute abdomen or gastrointestinal bleeding. Findings on physical examination may be inconsistent because of the variable location of the diverticulum, and bleeding may occur with no appreciable physical findings. Finally, small diverticula are often concealed by overlying small-bowel loops on routine small-bowel barium studies. The purposes of this article are to review the use of available techniques for the imaging diagnosis of Meckel's diverticulum, to discuss the relative advantages and indications for the various procedures, and to emphasize the role each plays in specific clinical circumstances. The embryology, anatomy, and clinical presentation of Meckel's diverticulum are also briefly discussed.

Hypertonic activation and recovery of system A amino acid transport in renal MDCK cells

Amino compounds are abundant within the renal inner medulla, but their possible role during hypertonic stress is not clear. Renal epithelial Madin-Darby canine kidney cells were used to examine the osmoregulation of system A transport, a major Na(+)-dependent process for neutral amino acid transport. System A activity was markedly increased after 6 h of hypertonic challenge, and intracellular alanine content increased more than twofold. The activation of system A was reversed after 24 h of hypertonic challenge. This downregulation was accompanied by the activation of betaine transport, as measured by gamma-aminobutyric acid uptake. Extracellular betaine prevented the early activation of system A. The hypertonic activation of system A was blocked by actinomycin D and cycloheximide. When cells were returned to isotonic medium after hypertonic activation, the recovery of system A transport also was partially inhibited by actinomycin D and puromycin. The results are consistent with the possibility that hypertonicity, by disrupting a repressor protein, leads to increased synthesis of a system A-related protein. The isotonic recovery may require synthesis of new repressor proteins.

The scapholunate allograft: a biomechanical feasibility study

The feasibility of a new method for reconstruction of the isolated scapholunate ligament tear with a scapholunate allograft was studied biomechanically using a fresh cadaver upper extremity model. Seven specimens were first tested intact for wrist range of motion, contact characteristics of the radiocarpal articulation, and relative motion of the scaphoid with respect to the lunate. Then a segment consisting of the radial third of the lunate, the adjoining scapholunate interosseus ligament, and the proximal pole of the scaphoid was resected. This segment was matched to a donor allograft of similar size and geometry, which was then placed into the recipient carpus and secured with one central transverse Kirschner wire and two shorter interfragmentary Kirschner wires placed into the lunate and scaphoid. The allografted specimen was subjected to the same tests as the intact wrist. Results showed that there were no significant differences in wrist range of motion, radiocarpal articular surface contact area and pressure, and relative flexion-extension rotation between the scaphoid and lunate during passive radioulnar deviation between the intact and allografted wrists.

[Phlebography with MR in the study of deep venous thrombosis]

MR phlebography was recently proposed as a possible alternative to contrast venography in the detection of deep venous thrombosis. We focused our work on the study of the pelvic veins since it is at this level that contrast venography and the other noninvasive techniques, i.e., phlebography, impedance plethysmography and US, exhibit their major limitations. Thirty patients underwent MR phlebography: 13 of them had a diagnosis of DVT of the pelvic venous district and the other 17 had negative results for this condition. All the patients were also examined with color-Doppler US at the pelvis and legs. In all the patients submitted to MR phlebography, thrombosis site and presence were demonstrated, with diagnostic information also on its extent and adhesion to vein wall. To conclude, MR phlebography can provide contrast venography-like images in a noninvasive way, with high accuracy (100% sensitivity and 90% specificity) especially in the pelvic district where the limitations of other techniques are more apparent. Larger series of patients must be studied to assess the actual role of MR phlebography in the patients with DVT or at high risk for this condition.