Focal cortical dysplasia and hemimegalencephaly: histological and neuroimaging correlations

BACKGROUND: The classification of cerebral cortical dysplasia is difficult and there are histological similarities between focal cortical dysplasia (FCD) and hemimegalencephaly. Objectives. To correlate the MR features and histological data of cortical dysplasias. MATERIALS AND METHODS: The MR appearances of 17 brains were examined. According to the signal intensity within the pathological area on T2-weighted (T2-W) sequences we selected two groups. RESULTS: Group 1 comprised ten patients with high signal in the dysplastic area on T2-W images. This group included five hemimegalencephalies, three frontal quadramegalencephalies, and one gyral dysplasia. The pathological hemisphere was reduced in size in one case. The cortex was thickened in all cases on T1-weighted (T1-W) images. There was loss of delineation between white matter (WM) and grey matter (GM) in all cases on both T1-W and T2-W sequences. The differential diagnosis with tumour, neoplastic-like malformation or polymicrogyria was questionable. Group 2 comprised seven patients presenting without increased signal within the dysplastic area on T2-W images. WM and GM were of similar signal intensity in six cases, and delineation between white and grey matter was absent in all cases. There were mild abnormalities on T1-W sequences in all cases. The dysplasias were limited to a lobe in five cases and a gyrus in two cases. In all cases, depiction of the malformation was a greater diagnostic problem than the differential diagnosis. CONCLUSIONS: A constant MR sign in our series was the loss of delineation between WM and GM in the dysplastic area. This correlated well with the observed histological disorganisation. Markedly high signal within the dysplastic area seems to be related to myelin abnormalities rather than glial cell abnormalities.     

Frontometaphyseal dysplasia: evidence for autosomal dominant inheritance

Frontometaphyseal dysplasia is a syndrome that encompasses cranial hyperostosis, abnormal tubulation of cylindrical bones, and other skeletal and extraskeletal abnormalities. The most striking features are overgrowth of the supraorbital ridges which results in a Mephistophelian facial appearance and a radiographic configuration of the skull that has been likened to a soldier's helmet. Most patients have severe hearing loss, defective dentition, poorly developed musculature, and joint contractures. Dominant inheritance has been suggested in previous reports, but an appropriate pedigree has been documented in only one family. This paper describes three additional patients in two unrelated families: (1) an 8-year-old boy whose mother has mild metaphyseal dysplasia and several minor skeletal abnormalities that have occurred in patients with the syndrome; and (2) two maternal half-brothers. These cases provide additional evidence that frontometaphyseal dysplasia is an autosomal dominant trait with variable penetrance.     

Right precordial leads and sudden death. Relation with arrhythmogenic right ventricular dysplasia

Non-coronary ST-segment elevation during right sided chest pain has been described in subjects with episodes of ventricular fibrillation at rest. This syndrome has been attributed to functional phenomena or to structural myocardial changes. A personal case has features belonging to two categories: ST-segment elevation observed before, during and after episodes of arrhythmia was compared to 11 previously recorded ECG recordings. Right ventricular dysplasia was shown by electrocardiography, electrophysiology and echocardiography. In addition, ST-segment elevation is classified in 3 categories: triangular and dome-shaped are the most commonly observed forms during the arrhythmias: the third form with "saddle"-shaped appearances has not been previously described and would seem to be a minor equivalent observed during intercritical periods. This form is found in 30% of clinically documented cases of arrhythmogenic right ventricular dysplasia.     

MR of cerebellar cortical dysplasia

MR imaging findings are described in four patients with cerebellar cortical dysplasia. Typically, cerebellar disorganized folia were seen as an irregular bumpy gray-white matter interface. In addition, cystlike cortical abnormalities were observed in two patients and associated supratentorial developmental abnormalities were seen in three patients. To our knowledge, cerebellar cortical dysplasia without supratentorial abnormalities, as seen in one patient, has not been reported before. We suggest that cerebellar cortical dysplasia represents a spectrum of abnormalities ranging from mild to extensive in severity.     

Bithalamic hyperintensity on T2-weighted MR: vascular causes and evaluation with MR angiography

PURPOSE: To determine whether MR angiography can be used to differentiate between the two vascular causes of bithalamic hyperintensity on T2-weighted MR images: "top of the basilar" artery occlusion and deep cerebral vein thrombosis. METHODS: A retrospective review identified six patients with bithalamic T2 hyperintensity of vascular causes. MR angiography was performed in four patients, MR angiography and conventional angiography in one patient, and conventional angiography in one patient. Data pertaining to clinical presentation and hospital course were collected. MR angiographic techniques were multislab overlapping three-dimensional time-of-flight, 2-D time-of-flight, and 2-D phase-contrast. RESULTS: Three cases of top of the basilar artery occlusion and three cases of deep cerebral vein thrombosis were recognized. In all cases, T2 hyperintensity in a vascular distribution suggested cerebral occlusive disease. Infarction involving the thalami and basal ganglia was present in two cases of deep cerebral vein thrombosis. Infarction of the thalami, mesodiencephalic region, and cerebellar hemispheres was present in two cases of basilar artery occlusion. Bithalamic infarction alone was seen in one case of deep cerebral vein thrombosis and one case of basilar artery occlusion. In the five cases in which MR angiography was used, this technique accurately distinguished the vessels involved (arterial or venous). CONCLUSION: MR angiography is a useful adjunct to MR imaging in the evaluation of bithalamic T2 hyperintensity. It does help distinguish between the two vascular causes: top of basilar artery occlusion and deep cerebral vein thrombosis.     

Brain stem encephalitis in childhood

OBJECTIVE: To present two cases of post-infectious encephalitis of the brain stem (ETC) in infancy, which is very infrequent at this age. CLINICAL CASES: Two patients aged 4 months and 9 months respectively had a previous history of a catarrhal illness a few days before the onset of encephalitis. The clinical condition was of subacute onset and torpid course, characterized by ataxia, reduced level of consciousness, involvement of the pyramidal tracts and paralysis of the cranial nerves. No significant information for the diagnosis of either case was obtained from CT. MR showed lesions at the level of the pons. However, the MR image did not correspond in seventy to the clinical condition. The clinical courses of the two patients were different. One case recovered with no sequelae. In the other case the cranial nerves and gait did not return to normal. CONCLUSIONS: In our experience, ETC is rarely seen in infancy. A high degree of suspicion and early treatment of ETC caused by the herpes simplex virus is necessary, since there is usually a high mortality or serious neurological sequelae.     

Mutation and expression of the XPA gene in revertants and hybrids of a xeroderma pigmentosum cell line

Achalasia is characterized by failure of relaxation of the lower esophageal sphincter and absence of progressive peristalsis in the esophageal body. Few data are available regarding the morphologic features of achalasia, in particular its histologic progression. The esophagi of 42 patients with achalasia treated with total thoracic esophagectomy were examined histologically in order to systematically identify morphologic features of clinically unresponsive achalasia and to determine what could be learned about the disease's evolution. In all cases, myenteric ganglion cells within the esophageal body were markedly diminished, with 20 specimens having none. Twenty specimens had residual ganglion cells in the proximal esophagus, and 15 specimens had a few randomly distributed ganglion cells in the mid- and distal portions of the esophagus. Inflammation within myenteric nerves, present in all cases, generally consisted of a mixture of lymphocytes and eosinophils, occasionally with plasma and mast cells. Focal replacement of myenteric nerves by collagen occurred in all cases, and there was almost complete replacement in several cases. Actual destruction of the residual ganglion cells was not seen. The resected esophagi also shared extramyenteric morphologic features. Some features probably stemmed from physiologic obstruction, such as muscular hypertrophy, mainly of the muscularis propria (all cases), with secondary degeneration and fibrosis (29 cases), and eosinophilia of the muscularis propria (22 cases). Other changes, probably resulting from chronic stasis of ingested materials in the lumen, included diffuse squamous hyperplasia (all cases), lymphocytic mucosal esophagitis (28 cases), lymphocytic inflammation of the lamina propria and submucosa with prominent germinal centers (all cases), and submucosal periductal or glandular inflammation with complete loss of submucosal glands in half of the cases. One patient had high-grade squamous dysplasia, and another had superficially invasive squamous cell carcinoma. A third group of changes was probably due to previous esophagomyotomy, including abnormal gastroesophageal reflux, as shown by pH reflux testing (13 cases) and Barrett's mucosa (four cases). In one case of Barrett's there was low-grade dysplasia. Clinically unresponsive, surgically resected achalasia has almost total loss of ganglion cells, and widespread destruction of myenteric nerves has already occurred. The only active component is myenteric inflammation. However, it cannot be determined whether this inflammation is a manifestation of ongoing nerve destruction or whether it is a secondary phenomenon.     

Prognostic features of cervical dysplasia associated with specific types of HPV DNA and cytologic features characteristic of HPV infection in dysplasia

OBJECTIVE: To study a possible etiologic relationship between the prognosis of uterine cervical dysplasia, association of type-specific human papillomavirus (HPV) DNA and cytologic features characteristic of HPV infection. STUDY DESIGN: Two hundred thirteen cases of uterine cervical dysplasia were selected in which follow-up survey for more than two years was possible. Frequency of the presence of HPV DNA in the DNA samples was determined by polymerase chain reaction. The cervical scrapings were also examined microscopically for the frequencies of cells with cytologic features characteristic of HPV infection. RESULTS: HPV was positive in 98 cases (46.0%). The high-risk type of HPV was detected at almost the same frequencies in both progressive and regressive states of dysplasia. Cytologic features were more evident in cells infected with the low-risk type of HPV. CONCLUSION: Involvement of an as-yet-unknown factor or factors coupled with infection with the high-risk type of HPV is implicated in the progression of uterine cervical dysplasia. Cytologic features characteristic of HPV infection may serve as a diagnostic marker for a favorable prognosis in dysplasia.     

The ex vivo effect of the herbal medicine sho-saiko-to on histamine release from rat mast cells

OBJECTIVE: This report describes subcutaneous sarcoidosis, focusing on the radiological and magnetic resonance (MR) features of the disease. DESIGN AND PATIENTS: The cases of four patients (one male and three female, age range 36-75 years) who had subcutaneous sarcoidosis with no other organs affected were reviewed. Lesions were nodular in two cases, and in the other two were diffuse. RESULTS: Computed tomography (CT) demonstrated a well-defined, homogeneous, and enhanced lesion in the nodular cases. However, in the diffuse cases, CT showed a heterogeneous, honeycomb-like appearance and little enhancement. Angiography showed a fine stain in the arterial phase. MR imaging of the nodular lesions was homogeneous with a signal intensity similar to muscle on T1-weighted images but heterogeneous with a higher signal than muscle on T2-weighted images. Diffuse lesions showed a striped or mesh pattern with intermediate signal intensity on both T1- and T2-weighted images. Contrast-enhanced MR images showed slight enhancement. CONCLUSIONS: Subcutaneous sarcoidosis should be considered in the differential diagnosis when a patient presents with the radiological and MR features described.     

Conservative management of small adenomata in ulcerative colitis

OBJECTIVE AND METHODS: Patients with chronic ulcerative colitis may develop colitis-related dysplasia and/or sporadic adenomata. Differentiating between these two processes is important because they may dictate different therapeutic approaches. Although distinguishing features of sporadic adenomata versus colitis-related dysplasia have been suggested previously on an a priori basis, they have never been verified by follow-up analysis. We have identified six chronic ulcerative colitis patients whose discrete adenomata were managed conservatively, with subsequent continuation in their surveillance programs. RESULTS: Mean patient age was 69 yr with a mean 21.3 yr of ulcerative colitis. Surveillance endoscopy of 63 patient-yr duration yielded 24 adenomata. A mean follow-up after the initial adenoma diagnosis was 7.2 yr with no carcinoma identified (including the examination of one prophylactic colectomy specimen). One patient, with a 34-yr history of ulcerative colitis and a single sporadic adenoma subsequently developed dysplasia of flat mucosa 14 months later. CONCLUSIONS: Our findings concur with previous reports and indicate that small, discrete adenomata with morphology identical to those seen in the general population occur in patients with ulcerative colitis. Such lesions in patients older than 45 yr, with tubular or tubulovillous architecture and low-grade dysplasia, are effectively treated by polypectomy only and are not necessarily an indication for colectomy. However, sporadic adenomata and colitis-related dysplasia can develop metachronously. It is suggested that subsequent to a diagnosis of sporadic adenoma in a patient with chronic ulcerative colitis, surveillance should increase to colonoscopic examination every 6 to 12 months.     

MRI of focal cortical dysplasia

We studied nine cases of focal cortical dysplasia (FCD) by MRI, with surface-rendered 3D reconstructions. One case was also examined using single-voxel proton MR spectroscopy (MRS). The histological features were reviewed and correlated with the MRI findings. The gyri affected by FCD were enlarged and the signal of the cortex was slightly increased on T1-weighted images. The gray-white junction was indistinct. Signal from the subcortical white matter was decreased on T1- and increased on T2-weighted images in most cases. Contrast enhancement was seen in two cases. Proton MRS showed a spectrum identical to that of normal brain.     

Suspected skeletal dysplasias: femur length to abdominal circumference ratio can be used in ultrasonographic prediction of fetal outcome

OBJECTIVES: Skeletal dysplasias are a group of bone growth disorders, some of which can be recognized prenatally. Certain types of skeletal dysplasias result in a lethal fetal outcome. The ability to predict this outcome prenatally would be important in counseling parents. This study evaluated the ratio of femur length to abdominal circumference as a predictor of fetal outcome in cases of suspected skeletal dysplasia. STUDY DESIGN: This 3-year retrospective study identified 18 cases of prenatally suspected skeletal dysplasia from a population of approximately 35,000 fetuses undergoing prenatal ultrasonography. The femur length/abdominal circumference ratio was calculated and compared with fetal-neonatal outcomes and diagnoses. RESULTS: Eighteen cases of suspected skeletal dysplasia were identified, and the femur length/abdominal circumference ratio was found to be a good predictor of fetal outcome independent of gestational age. A ratio < 0.16 resulted in a lethal outcome in nine of nine cases. Conversely, a ratio > or = 0.16 resulted in a diagnosis of a nonlethal form of skeletal dysplasia or a diagnosis that ruled out any form of skeletal dysplasia in nine of nine cases. CONCLUSIONS: The femur length/abdominal circumference ratio may be useful to predict a lethal fetal outcome when ultrasonography indicates a possible skeletal dysplasia.     

Osteonecrosis after contact neodymium:yttrium aluminum garnet arthroscopic laser meniscectomy

OBJECTIVE: The purpose of this report is to describe two cases of osteonecrosis that occurred after arthroscopic meniscectomy with a contact neodymium:yttrium aluminum garnet laser system. The patients developed increasing knee pain and disability 5 months and 6 months after laser meniscectomy. MR imaging showed subchondral osteonecrosis in the femoral condyle and tibial plateau immediately adjacent to the site of laser meniscectomy in both patients. One patient required a total knee replacement to alleviate knee symptoms, and the other patient required a tibial osteotomy and surgical elevation of collapsed tibial articular surface. CONCLUSION: To our knowledge, this complication of laser arthroscopic meniscectomy has not been reported in the radiology literature. The clinical and MR imaging features of this important complication are described and possible causative mechanisms are discussed.     

MR cholangiography in the examination of patients with biliary-enteric anastomoses

OBJECTIVE: The aim of our study was to determine the role of MR cholangiography in the noninvasive examination of patients with biliary-enteric anastomoses. SUBJECTS AND METHODS: Twenty-four patients (nine men and 15 women; mean age, 68.9 years old) with biliary-enteric anastomoses underwent MR cholangiography. We used a fat-suppressed three-dimensional turbo spin-echo sequence (3000/700 [TR/TE]; echo train length, 128) with no breath-hold, optimized with a 0.5-T magnet. Imaging studies were performed because of scheduled follow-up (five patients), persistent jaundice (six patients), cholangitis and abnormal liver function (eight patients), and a combination of transient jaundice, epigastric pain, and abnormal liver function (five patients). RESULTS: Image quality was graded from optimal to good in 21 (88%) of 24 cases and poor in three (13%) of 24 cases. The degree of bile duct dilatation was correctly assessed, with complete agreement between the two observers in all cases. MR cholangiography correctly showed bile duct irregularities in six of the eight patients with cholangitis (kappa = .59), anastomotic strictures in all 19 patients with strictures (kappa = .86), and 3- to 15-mm stones in nine of 10 patients (kappa = .95). A slight overestimation of the strictures occurred in four of the 19 cases with strictures. CONCLUSION: MR cholangiography is a reliable imaging technique for the examination of patients with biliary-enteric anastomoses.     

Evidence against flat dysplasia as a regional field defect in small bowel adenocarcinoma associated with celiac sprue

OBJECTIVE: To determine whether diffuse flat dysplasia, akin to that seen with chronic ulcerative colitis, occurs as a mucosal field defect accompanying small bowel adenocarcinoma in patients with celiac sprue. DESIGN: A pathologic investigation of archival tissue was undertaken. MATERIAL AND METHODS: From the tissue archives at Mayo Clinic Rochester for the period from January 1978 to January 1993, resected sprue-associated adenocarcinomas with adequate adjacent mucosa for study were identified. On the basis of multiple strip biopsy specimens obtained at the tumor margins and within 4 cm distal and proximal to the tumor, histologic maps were created. RESULTS: Among 94 patients with primary adenocarcinoma of the small bowel, 8 had a concurrent diagnosis of celiac sprue. Of these eight cases, six surgically resected specimens (five duodenal and one jejunal adenocarcinoma) were adequate for study. A thin rim of benign dysplasia was demonstrated at the tumor margin in three of the six specimens; however, contiguous fields of flat dysplasia were not present in any of these cases. CONCLUSION: These data support focal dysplasia (for example, adenoma) rather than sheets of flat dysplasia as the premalignant lesion in sprue-associated small bowel adenocarcinoma. Blind endoscopic biopsies of small bowel mucosa are not justified for neoplasia surveillance in patients with celiac sprue.     

Detection of four species of Borrelia burgdorferi sensu lato in Ixodes ricinus ticks collected from roe deer (Capreolus capreolus) in The Netherlands

Epiglottic disruption is an uncommon injury usually associated with significant supraglottic trauma. This injury may be overlooked because of the difficulty in examining the larynx or other associated severe injuries. We present two cases of clinically unsuspected epiglottic disruption that were first seen on MR images of the neck.     

Ovarian dysplasia in epithelial inclusion cysts. A morphometric approach using neural networks

BACKGROUND: Ovarian dysplasia has been described in the ovarian surface epithelium by histologic and morphometric studies. This study evaluates ovarian dysplasia in epithelial inclusion cysts adjacent to overt carcinoma and also incidentally found in ovaries removed for nonneoplastic diseases, including oophorectomies for family history of ovarian cancer, using an artificial neural network. METHODS: Histologic sections from 37 ovaries of which 26 were diagnosed with dysplasia in epithelial inclusion cysts (10 adjacent to carcinoma and 16 incidental) and 11 with benign epithelial inclusion cysts were evaluated by tracing nuclear profiles and assessing measures of nuclear area, shape, and texture. These sections were analyzed using artificial neural networks and also statistically using the Kruskal-Wallis test with the Dunn procedure to compare the morphologic similarity of dysplasia found incidentally in inclusion cysts unrelated to carcinoma from that in inclusion cysts adjacent to carcinoma. RESULTS: Neither statistical nor artificial neural network analysis was able to distinguish between incidental and adjacent dysplasia. Both types differed significantly from the control cases. CONCLUSIONS: Neural networks are powerful classification tools when applied to multiple variables extracted from individual cases. In this study, they helped to substantiate the similarity between dysplasia found incidentally and that adjacent to ovarian carcinoma. Because dysplasia represents a potential precancerous lesion, its incidental finding may help identify patients at risk for developing ovarian carcinoma.     

Ultrastructural pathology of the sperm flagellum: association between flagellar pathology and fertility prognosis in severely asthenozoospermic men

An ultrastructural study of spermatozoa in a series of 247 severely asthenozoospermic patients disclosed two kinds of anomalies. The first was dysplasia of the fibrous sheath, a primary defect of spermatozoa with hypertrophy and hyperplasia of the fibrous sheath, associated axonemal anomalies, familial incidence and chronic respiratory disease. The patients could be divided into two subgroups: the complete form (all spermatozoa affected) and the incomplete form (alterations in 70-80% spermatozoa). There were no spontaneous or in-vitro fertilization (IVF) pregnancies. Intracytoplasmic sperm injection (ICSI) in six patients resulted in successful fertilizations, but only two pregnancies were obtained. These features configure a phenotype that suggests a genetic origin. The second anomaly was non-specific flagellar anomaly (NSFA), random secondary flagellar alterations affecting variable numbers of spermatozoa, without respiratory disease or familial incidence. 54 men with NSFA were followed for 2-6 years. Of these, 18 achieved conception, either spontaneous or by means of assisted fertilization, followed by 14 pregnancies and 12 live births. Their sperm motility significantly increased during the follow-up period. In the remaining 36 men motility did not change during the follow-up period and there were no fertilizations or pregnancies. We conclude that in severe asthenozoospermia, ultrastructural examination of spermatozoa has an effective prognostic value, identifying two syndromes with very different flagellar alterations and fertility potentials.     

Quantitative analyses for facial nerve MR imaging

It is clear, from our clinical experience, that the facial nerve in patients with facial palsy is enhanced on magnetic resonance (MR) imaging after intravenous administration of gadolinium diethylenetriamine. However, some problems with clinical reliability persist. There have been reports that normal facial nerves often show enhancement on MR imaging. We also question whether there are any differences in the degree of enhancement between Bell's palsy and Ramsay Hunt syndrome. To solve these problems, analyses were conducted using a personal computer by means of digital image-processing to measure the gray scale levels of enhanced facial nerves on MR imaging films. Seventeen cases of Bell's palsy, eight cases of Ramsay Hunt syndrome and fourteen normal subjects whose facial nerves showed enhancement on MR imaging were selected for the analyses. The concept of a facial nerve/whole image ratio (F/W ratio), analyzing the degree of enhancement of the facial nerve quantitatively, is introduced in this paper. The F/W ratio is the ratio of the gray scale level of the facial nerve region to the highest gray scale level in the skull at the MR imaging film. When the F/W ratios of these subjects were analyzed, no significant differences were found between Bell's Palsy and Ramsay Hunt syndrome in the degree of enhancement; facial palsy cases showed quantitatively larger F/W ratios than normal subjects.