A Newly Identified Frontal Path from Fornix in Septum Pellucidum with 7.0T MRI Track Density Imaging (TDI) - The Septum Pellucidum Tract (SPT)

The high anatomical contrast achieved with the newly emerging MRI tractographic technique of super-resolution track density imaging (TDI) encouraged us to search for a new fiber tract in the septum pellucidum. Although this septum pellucidum tract (SPT) has been observed previously, its connections were unclear due to ambiguity and limited resolution of conventional MRI images. It is now possible to identify detailed parts of SPT with the increased resolution of TDI, which involves diffusion MRI imaging, whole-brain tractography, and voxel subdivision using the track-count information. Four healthy male subjects were included in the study. The experiment was performed with 7.0T MRI, following the guidelines of the institute's institutional review board. Data were processed with the super-resolution TDI technique to generate a tractographic map with 0.18 mm isotropic resolution. The SPT was identified in all subjects. Based on additional seed tracking method with inter-axis correlation search, we have succeeded in identifying a new frontal lobe pathway in the SPT. We hypothesize that the tract is connected as a superior dorsal branch of the fornix that leads to the prefrontal cortex.

Neural substrates of Hanja (Logogram) and Hangul (Phonogram) character readings by functional magnetic resonance imaging

The two basic scripts of the Korean writing system, Hanja (the logography of the traditional Korean character) and Hangul (the more newer Korean alphabet), have been used together since the 14th century. While Hanja character has its own morphemic base, Hangul being purely phonemic without morphemic base. These two, therefore, have substantially different outcomes as a language as well as different neural responses. Based on these linguistic differences between Hanja and Hangul, we have launched two studies; first was to find differences in cortical activation when it is stimulated by Hanja and Hangul reading to support the much discussed dual-route hypothesis of logographic and phonological routes in the brain by fMRI (Experiment 1). The second objective was to evaluate how Hanja and Hangul affect comprehension, therefore, recognition memory, specifically the effects of semantic transparency and morphemic clarity on memory consolidation and then related cortical activations, using functional magnetic resonance imaging (fMRI) (Experiment 2). The first fMRI experiment indicated relatively large areas of the brain are activated by Hanja reading compared to Hangul reading. The second experiment, the recognition memory study, revealed two findings, that is there is only a small difference in recognition memory for semantic transparency, while for the morphemic clarity was much larger between Hanja and Hangul. That is the morphemic clarity has significantly more effect than semantic transparency on recognition memory when studies by fMRI in correlation with behavioral study.

Anterior commissure--posterior commissure revisited

Objective

The anterior commissure (AC) and posterior commissure (PC) are the two distinct anatomic structures in the brain which are difficult to observe in detail with conventional MRI, such as a 1.5T MRI system. However, recent advances in ultra-high resolution MRI have enabled us to examine the AC and PC directly. The objective of the present study is to standardize the shape and size of the AC and PC using a 7.0T MRI and to propose a new brain reference line.

Materials and Methods

Thirty-four, 21 males and 13 females, healthy volunteers were enrolled in this study. After determining the center of each AC and PC, we defined the connection of these centers as the central intercommissural line (CIL). We compared the known extra- and intra-cerebral reference lines with the CIL to determine the difference in the angles. Additionally, we obtained horizontal line from flat ground line of look front human.

Results

The difference in angle of the CIL and the tangential intercommissural line (TIL) from the horizontal line was 8.7 ± 5.1 (11 ± 4.8) and 17.4 ± 5.2 (19.8 ± 4.8) degrees in males and females, respectively. The difference in angle between the CIL and canthomeatal line was 10.1 in both male and female, and there was no difference between both sexes. Likewise, there was no significant difference in angle between the CIL and TIL between both sexes (8.3 +/- 1.1 in male and 8.8 +/- 0.7 in female).

Conclusion

In this study, we have used 7.0T MRI to define the AC and PC quantitatively and in a more robust manner. We have showed that the CIL is a reproducible reference line and serves as a standard for the axial images of the human brain.

Super-resolution track-density imaging of thalamic substructures: comparison with high-resolution anatomical magnetic resonance imaging at 7.0T

The thalamus is one of the most important brain structures, with strong connections between subcortical and cortical areas of the brain. Most of the incoming information to the cortex passes through the thalamus. Accurate identification of substructures of the thalamus is therefore of great importance for the understanding of human brain connectivity. Direct visualization of thalamic substructures, however, is not easily achieved with currently available magnetic resonance imaging (MRI), including ultra-high field MRI such as 7.0T, mainly due to the limited contrast between the relevant structures. Recently, improvements in ultra-high field 7.0T MRI have opened the possibility of observing thalamic substructures by well-adjusted high-resolution T1 -weighted imaging. Moreover, the recently developed super-resolution track-density imaging (TDI) technique, based on results from whole-brain fiber-tracking, produces images with sub-millimeter resolution. These two methods enable us to show markedly improved anatomical detail of the substructures of the thalamus, including their detailed locations and directionality. In this study, we demonstrate the role of TDI for the visualization of the substructures of the thalamic nuclei, and relate these images to T1-weighted imaging at 7.0T MRI.

Seven-Tesla magnetic resonance images of the substantia nigra in Parkinson disease

OBJECTIVE

To investigate anatomical changes in the substantia nigra (SN) of Parkinson disease (PD) patients with age-matched controls by using ultra-high field magnetic resonance imaging (MRI).

METHODS

We performed 7T MRI in 10 PD and 10 age-matched control subjects. Magnetic resonance images of the SN were obtained from a 3-dimensional (3D) T(2)*-weighted gradient echo sequence. Region of interest-based 3D shape analysis was performed to quantitatively compare images from the 2 groups.

RESULTS

The boundary between the SN and crus cerebri was not smooth in PD subjects. Undulation in the lateral surface of the SN appeared more intense in the side contralateral to that with the more severe symptoms, and more prominent at the rostral level of the SN than at the intermediate or caudal levels. In addition to the lateral surface, there was a striking difference in the dorsomedial aspects of the SN between PD and control subjects. In control subjects, a brighter signal region was observed along the dorsomedial surface of the lateral portion of SN, whereas in PD subjects, this region was observed as a dark region containing a hypointense signal in T(2)*-weighted images. The measurement of SN volumes, normalized to the intracranial volumes, showed higher values in PD subjects than in control subjects.

INTERPRETATION

This study demonstrates that 3D 7T MRI can definitively visualize anatomical alterations occurring in the SN of PD subjects. Further pathological studies are required to elucidate the nature of these anatomical alterations.

Observation of glucose metabolism in the thalamic nuclei by fusion PET/MRI

The anatomy of the thalamus and its connectivity with surrounding areas are known. Localized metabolic activities at the thalamic substructural level have not been measured in vivo in human brains because of limited resolution and contrast.

METHODS

The energy metabolism and fine anatomic structures of the thalamus were measured simultaneously in 5 healthy subjects using a PET/MRI fusion imaging system. Measured metabolism in individual thalamic nuclei was quantified by corresponding PET/MRI images.

RESULTS

Substructures of the thalamus were clearly distinguished in 7.0-T MRI images, and the corresponding metabolic activities measured by PET were integrated by the PET/MRI system. The medial dorsal thalamic nucleus consistently showed the highest glucose uptake among the thalamic nuclei.

CONCLUSION

These results demonstrate that substructure-specific metabolic activities in the thalamus can be measured with a PET/MRI system consisting of an ultra-high-resolution PET component and an ultra-high-field MRI component.

Direct visualization of Parkinson's disease by in vivo human brain imaging using 7.0T magnetic resonance imaging

Parkinson's disease (PD) is a neurodegenerative disorder resulting from progressive loss of dopaminergic neurons in the substantia nigra (SN) pars compacta. Therefore, imaging of the SN has been regarded to hold greatest potential for use in the diagnosis of PD. At the 7.0T magnetic resonance imaging (MRI), it is now possible to delineate clearly the shapes and boundaries of the SN. We scanned eight early and two advanced PD patients, along with nine age-matched control subjects, using a 7.0T MRI in an attempt to directly visualize the SN and quantify the differences in shape and boundaries of SN between PD subjects in comparison with the normal control subjects. In the normal controls, the boundaries between the SN and crus cerebri appear smooth, and clean "arch" shapes that stretch ventrally from posterior to anterior. In contrast, these smooth and clean arch-like boundaries were lost in PD subjects. The measured correlation analyses show that, in PD patients, there is age-dependent correlation and substantially stronger UPDRS motor score-dependent correlation. These results suggest that, by using 7.0T MRI, it appears possible to use these visible and distinctive changes in morphology as a diagnostic marker of PD.

Segmentation of cerebral gyri in the sectioned images by referring to volume model

Authors had prepared the high-quality sectioned images of a cadaver head. For the delineation of each cerebral gyrus, three-dimensional model of the same brain was required. The purpose of this study was to develop the segmentation protocol of cerebral gyri by referring to the three-dimensional model on the personal computer. From the 114 sectioned images (intervals, 1 mm), a cerebral hemisphere was outlined. On MRIcro software, sectioned images including only the cerebral hemisphere were volume reconstructed. The volume model was rotated to capture the lateral, medial, superior, and inferior views of the cerebral hemisphere. On these four views, areas of 33 cerebral gyri were painted with colors. Derived from the painted views, the cerebral gyri in sectioned images were identified and outlined on the Photoshop to prepare segmented images. The segmented images were used for production of volume and surface models of the selected gyri. The segmentation method developed in this research is expected to be applied to other types of images, such as MRIs. Our results of the sectioned and segmented images of the cadaver brain, acquired in the present study, are hopefully utilized for medical learning tools of neuroanatomy.

Substructural hippocampal glucose metabolism observed on PET/MRI

The hippocampus is one of the best-known neural structures in the brain and has been of interest in observing the substructures and their metabolic functions. However, it has been difficult to distinguish its substructures and functions in vivo because of its small size.

METHODS

(18)F-FDG PET and high-resolution MRI of the hippocampus were performed on 5 healthy subjects using a PET/MRI system. The metabolism of each hippocampal substructure was measured in vivo on the basis of the MR images.

RESULTS

The dentate gyrus and cornu ammonis 4 showed the highest glucose uptake in the healthy subjects.

CONCLUSION

Measuring glucose metabolism in the substructures of the hippocampus could provide a new tool for the future investigation of related brain diseases or functional studies, such as Alzheimer disease or memory and learning studies.

Direct visualization of deep brain stimulation targets in Parkinson disease with the use of 7-tesla magnetic resonance imaging

OBJECT

A challenge associated with deep brain stimulation (DBS) in treating advanced Parkinson disease (PD) is the direct visualization of brain nuclei, which often involves indirect approximations of stereotactic targets. In the present study, the authors compared T2*-weighted images obtained using 7-T MR imaging with those obtained using 1.5- and 3-T MR imaging to ascertain whether 7-T imaging enables better visualization of targets for DBS in PD.

METHODS

The authors compared 1.5-, 3-, and 7-T MR images obtained in 11 healthy volunteers and 1 patient with PD.

RESULTS

With 7-T imaging, distinct images of the brain were obtained, including the subthalamic nucleus (STN) and internal globus pallidus (GPi). Compared with the 1.5- and 3-T MR images of the STN and GPi, the 7-T MR images showed marked improvements in spatial resolution, tissue contrast, and signal-to-noise ratio.

CONCLUSIONS

Data in this study reveal the superiority of 7-T MR imaging for visualizing structures targeted for DBS in the management of PD. This finding suggests that by enabling the direct visualization of neural structures of interest, 7-T MR imaging could be a valuable aid in neurosurgical procedures.

A proposal of new reference system for the standard axial, sagittal, coronal planes of brain based on the serially-sectioned images

Sectional anatomy of human brain is useful to examine the diseased brain as well as normal brain. However, intracerebral reference points for the axial, sagittal, and coronal planes of brain have not been standardized in anatomical sections or radiological images. We made 2,343 serially-sectioned images of a cadaver head with 0.1 mm intervals, 0.1 mm pixel size, and 48 bit color and obtained axial, sagittal, and coronal images based on the proposed reference system. This reference system consists of one principal reference point and two ancillary reference points. The two ancillary reference points are the anterior commissure and the posterior commissure. And the principal reference point is the midpoint of two ancillary reference points. It resides in the center of whole brain. From the principal reference point, Cartesian coordinate of x, y, z could be made to be the standard axial, sagittal, and coronal planes.

Quantitative analysis of the hippocampus using images obtained from 7.0 T MRI

In-vivo volumetric measurements of hippocampus have proven to be highly informative for studying various neurological diseases such as Alzheimer's disease. The usefulness of volumetric imaging, however, has been limited due to the poor image resolutions obtained by currently available MRI images. In this study, a new result of volumetric image measurement of the hippocampus using 7.0 T MRI images of high contrast and resolution is described. To verify the usefulness of the proposed method, its reliability and sensitivity were examined and compared with existing imaging techniques such as 1.5 T or 3.0 T MRI imaging. The results of our study with 7.0 T MRI clearly demonstrated superior boundary detection for the hippocampal head, body, and tail compared with low field MRIs. In conclusion, robust and reproducible volumetric measurements as well as 3D images of clear contrast obtained with 7.0 T suggest the usefulness of high field MR imaging and its eventual use for the accurate diagnosis of hippocampal diseases and related research.

Delayed bleeding after gamma knife surgery for meningioma

We report the occurrence of haemorrhage in a meningioma after gamma knife surgery.A 52-year-old woman had undergone gamma knife radiosurgery for a growing meningioma in the left tentorial hiatus three years earlier (A radiation dose of 15 Gy was administered to the margin, with a maximum dose of 30 Gy, Fig. 1a). The size of the mass decreased steadily, and central lucency was seen in the follow-up magnetic resonance images, a usual finding seen after gamma knife surgery (MRI, Fig. 1b). However, a MRI taken at the 30-month follow-up showed the tumour to be swollen, and peritumoural oedema had increased (Fig. 1c). Three years later, apoplectic symptoms occurred, and computed tomography revealed a peritumoural haemorrhage, with oedema (Fig. 1d). An emergency craniotomy was carried out, and the biopsy showed a transitional type of meningioma, with vasculopathy and necrosis. After operation she had a right hemiparesis and a visual defect.

Sclerosing meningioma: immunohistochemical analysis of five cases

Sclerosing meningioma is a rare morphologic subtype of meningioma and may be mistaken for atypical or malignant meningioma and astrocytoma or schwannoma because of marked collagen deposits and a sparse population of cells with little resemblance to meningothelial cells. Authors describe the histopathologic and immunophenotypic features of five cases of sclerosing meningioma. Histologically, all the cases consisted of paucicellular collagenous tissue containing spindle cells with or without small foci of meningothelial cell proliferation. The morphology and immunohistochemical profile of the spindle cells were different from those of conventional meningothelial cells. The meningothelial cells showed a typical immunoreactivity of conventional meningiomas, while the spindle cells displayed a strong expression of vimentin. The Ki-67 labelling index was uniformly low in all cases, and none of cases expressed p53 protein. In summary, the recognition of meningothelial cells in massively sclerotic lesions is helpful for a correct diagnosis. In the cases with a total absence of meningothelial cells, however, the vague collagenous whorls are more diagnostic rather than immunohistochemistry. Considering association with clear cell meningioma, prospective and retrospective long-term follow-up is necessary for deciding whether reminiscent clear cell meningiomas should be separated from sclerosing meningioma or not.

Temporal lobe epilepsy caused by choroid plexus papilloma in the temporal horn

Choroid plexus papilloma (CPP) arising in the temporal horn is rare in adult population, and to the best of our knowledge, there has been no report of such a case with temporal lobe epilepsy (TLE). The authors describe a unique case of a 27-year-old woman who was diagnosed as TLE and was found to have a CPP in the temporal horn. Choroid plexus papilloma of the temporal horn, even though rare, can be found in adult population and be causally related to temporal lobe epilepsy.

The significance of gemistocytes in astrocytoma

BACKGROUND

A retrospective clinical analysis of astrocytomas which contained a significant proportion of gemistocytes was carried out in order to evaluate their effect on prognosis, and other factors influencing prognosis.

METHOD

From 253 consecutive cases of astrocytic tumours in adults, 25 were selected who had more than 20% gemistocytes in every high-power field examined. 9 of these had anaplasia, the remainder did not. They were divided into two groups according to the proportion of gemistocytes; group A, contained more than 60% gemistocytes, and group B, had between 20 and 60% gemistocytes. TUNEL and immunohistochemical staining for PCNA, p53, Ki-67, bcl-2 were performed in the 20 available cases.

FINDINGS

The median follow-up period was 46 months. There were 14 recurrences, with a median time to recurrence of 15 months. Thirteen repeat operations were performed in nine cases, and two cases showed recurring malignant transformation. The overall median survival time following diagnosis was 73 months and the 5-year survival rate was 52%. There were no significant differences in median survival between groups A and B with different proportions of gemistocytes. On the other hand the median survival of the gemistocytic astrocytomas with anaplasia was 25 months, compared with 158 months for those without anaplasia (p=0.0005). The significant impact of anaplasia on survival persisted in both groups. There were no significant differences in immunohistochemical staining between the two groups, with the exception of staining for Ki-67 (means of the two groups: group A 1.40; group B 2.50).

CONCLUSIONS

It is suggested that the proportion of gemistocytes does not itself affect prognosis.

Ischemic intensity influences the distribution of delayed infarction and apoptotic cell death following transient focal cerebral ischemia in rats

The aim of this study was to investigate whether the apoptotic process contributes to the delayed infarction that follows a middle cerebral artery (MCA) occlusion of 20 min (mild ischemia group) and to compare this with the delayed component of infarct following 2 h of MCA occlusion (severe ischemia group). Adult male Sprague-Dawley rats underwent left MCA occlusion for either 20 min or 2 h and were reperfused for 12, 24 and 72 h. On 2,3,5-triphenyltetrazolium chloride-stained coronal sections, delayed infarction was observed to develop in the whole MCA territory after mild ischemia, and also in the frontoparietal cortex after severe ischemia. At 24 h after 20 min of MCA occlusion, characteristic apoptotic features, including chromatin condensation and apoptotic bodies were frequently observed by electron microscopy. In both ischemic groups, Hoechst 33342 staining showed typically condensed and fragmented nuclei in the area showing delayed infarction, where TdT-dUTP nick end labeling (TUNEL)-positive cells were also significantly increased. Caspase-3 activity was also found to be elevated 24 and 72 h after reperfusion and this peaked at 24 h in both groups. These findings suggest that ischemic severity may influence the distribution of delayed infarction, and that apoptosis is the underlying pathophysiologic mechanism.

Childhood meningiomas associated with meningioangiomatosis: report of five cases and literature review

Meningioangiomatosis is a unique, rare hamartomatous lesion. Meningiomas arising in the background of meningioangiomatosis are rare conditions which pathologically and radiologically mimic invasive meningiomas, but have a benign clinical course in children and young adults. In this study, five such cases are reported. To our knowledge, this is the largest reported collection of meningiomas associated with meningioangiomatosis. Less immunoreactivity for progesterone receptor and high Ki-67 labelling index are generally known to be associated with invasive meningiomas. However, high expression of progesterone receptor and low Ki-67 labelling index in the present cases supports the idea that brain invasion is not an indicator of malignancy but an independent finding associated with meningiomas which have arisen from meningioangiomatosis. We emphasize the good prognosis of such tumours and discuss pathogenesis of meningiomas with meningioangiomatosis.

Cerebral germinoma with hemiatrophy of the brain: report of three cases

BACKGROUND

The authors report three cases of cerebral germinoma that occurred in young adults with unusual presentation.

METHOD

All three patients presented with hemiparesis and were treated at Seoul National University. A histological diagnosis of germinoma was made by a stereotactic biopsy in all three cases.

FINDINGS

Magnetic resonance (MR) images showed that their tumors were located in the internal capsule and thalamus, and were associated with ipsilateral cerebral hemisphere and brain stem atrophy. The hemiparesis slowly progressed and this was accompanied by a haemorrhagic cyst in each patient.

INTERPRETATION

Clinical diagnosis was not easy because of the unusual clinical presentations and atypical MR imaging findings. It is suggested that cerebral germinoma should be included in the differential diagnosis of a haemorrhagic mass which is associated with cerebral atrophy in the thalamus, basal ganglia, or internal capsule, especially in adolescents or young adults.

Intramedullary immature teratoma in a young infant involving a long segment of the spinal cord

Intramedullary teratoma is a rare lesion, located in the majority of cases in the lumbosacral area, and such lesions involving an extensive area of the spinal cord in young infants have seldom been reported. We present the case of a 3-month-old girl with an intramedullary spinal immature teratoma extending from C-5 to T-12, which was totally removed. The patient had suffered from paraplegia for 15 days, after which spinal MRI revealed a heterogeneously enhancing intramedullary lesion. Biopsy of the lesion demonstrated mature intestinal tissue. After total removal of the tumor, paraplegia and sphincter disturbances improved. Intramedullary teratoma should be included in the differential diagnosis of holocord tumors in young infants with rapidly progressing symptoms and if found should be radically excised. This case also emphasizes the importance of histological diagnosis and demonstrates the possibility of neurological recovery even in the case of paraplegia lasting for more than 1 month in a young infant.

Histo-topographic distribution of acute inflammation of the human umbilical cord

Acute inflammation of the umbilical cord, acute funisitis, is a sign of fetal inflammatory response, and the clinicopathological need for its identification is increasing. This study was conducted in order to describe the topographic distribution of acute funisitis, and thereby to provide more information on the intrinsic nature of acute funisitis and find a better way of pathologically examining the umbilical cord. A total of 10 umbilical cords affected by acute funisitis were histopathologically examined throughout their entire lengths at 1 mm intervals. Pathological examination was done to characterize the extent of the funisitis, the involvement of the vein (phlebitis) or of one or both arteries (arteritis), and the presence of inflammation in Wharton's jelly. Umbilical cord plasma interleukin (IL)-6 was measured by specific immunoassay to assess whether or not the severity of acute funisitis correlates with fetal cytokine response. It would appear that the inflammatory reaction begins as a discrete, multifocal process which eventually becomes contiguous as the inflammatory reaction proceeds. Umbilical cord plasma IL-6 concentrations tended to correlate with the extent of umbilical cord inflammation. The initial phase of acute funisitis involves discrete and multiple foci along the length of the umbilical cord. Moreover, the extent of acute funisitis reflects the severity of systemic fetal cytokine response. Therefore, adequate sampling using multiple sections would facilitate the identification of acute funisitis. We propose a standard sampling procedure taking one section from each third of the umbilical cord.

Childhood meningioma: unusual location, atypical radiological findings, and favorable treatment outcome

OBJECTS

To investigate the characteristics of childhood meningioma, especially, locations, radiological findings, pathological features (including proliferative potential) and outcome, 11 children with meningiomas were retrospectively analyzed.

RESULTS

Unusual location, large size, frequent calcification, and cyst formation were characteristic radiological findings. Gross total resection was achieved in 8 patients, and there was recurrence in 2. Gamma knife radiosurgery was performed on residual and recurrent tumors. MIB-1 indices tended to be high in large tumors. Nine patients had a Karnofsky Performance Scale of more than 70 during the follow-up period of 10 months to 19.5 years. Surgical treatment rendered 4 of 5 epileptic patients seizure free. The childhood meningiomas examined had unusual locations, atypical radiological findings, and various proliferative potentials.

CONCLUSIONS

Complete resection is the treatment of choice. Gamma knife radiosurgery can be a good alternative for residual tumors and small recurrent tumors. The outcome of childhood meningiomas is good after surgery.

Radical excision of pediatric craniopharyngioma: recurrence pattern and prognostic factors

The purpose of our study was to investigate the pattern of recurrence and the prognostic factors for recurrence of pediatric craniopharyngiomas after radical excision. A series of 36 patients with craniopharyngiomas (21 boys and 15 girls; age range 1-15 years; mean 7.3 years) were reviewed. All patients had undergone radical excision without radiotherapy. The mean follow-up period was 52 months (range 1-149 months). Tumors recurred in 14 patients within 83 months (mean 31.4 months). The overall 5-year recurrence-free survival rate was 55%. Regular neuroimaging follow-up detected tumor recurrence while the lesions were still small before symptoms developed (P<0.05). At the first surgical procedure, the optic nerve/chiasm (n=23) was the most common adhesion site. The most frequent sites of recurrence were the optic nerve/chiasm (n=6) and the pituitary fossa (n=6). Tumor location was the single significant clinical predictor of recurrence. The 5-year recurrence-free survival rate was 39% for those who had an intrasellar tumor component and 81% for those who did not (P<0.05). The Ki-67 labeling indices (LIs) of primary tumors did not have prognostic value for recurrence. Recurrent tumors tended to have higher Ki-67 LIs than their primary counterparts. On the basis of this study, we concluded that craniopharyngiomas with intrasellar components should be followed cautiously and the necessity for regular follow-up should be emphasized, even when the tumor is "totally" resected.

Fatal submassive hepatic necrosis associated with tyrosine-methionine-aspartate-aspartate-motif mutation of hepatitis B virus after long-term lamivudine therapy

We present a case of infection with lamivudine-resistant mutant hepatitis B virus (HBV) that fatally exacerbated hepatitis following the emergence of HBV with mutations in the tyrosine-methionine-aspartate-aspartate (YMDD) motif in an immunocompetent patient who was receiving long-term lamivudine therapy. Restriction fragment length polymorphism analysis showed that the YMDD-motif mutant was the predominant form of circulating HBV at the time of the fatal exacerbation, and a necropsy specimen of the liver revealed submassive hepatic necrosis without steatosis.

Cerebellopontine angle ganglioglioma: MR findings

We present a case of cerebellopontine (CP) angle ganglioglioma in a young child with developmental delay and no trigeminal nerve symptoms. MR imaging demonstrated a mass of homogeneous low signal intensity in the left CP angle on T1-weighted images with no enhancement with gadolinium, and of relatively homogeneous high signal intensity on T2-weighted images.

Umbilical arteritis and phlebitis mark different stages of the fetal inflammatory response

OBJECTIVE

Funisitis, the inflammation of the umbilical cord determined by histologic examination of the placenta, is evidence of a fetal inflammatory response. The inflammatory process may involve the umbilical vein (phlebitis) and one or both umbilical arteries (arteritis) and extend into the Wharton's jelly. This study was conducted to examine whether the pattern of inflammation of the umbilical cord correlates with a biochemical marker of systemic fetal inflammation (umbilical cord plasma interleukin-6) and an adverse neonatal outcome.

STUDY DESIGN

This cohort study included 636 cases of preterm delivery (<36 weeks) with or without inflammation of the umbilical cord. Umbilical cord blood was collected at the time of delivery. The aim of pathologic examination was to characterize the extent of umbilical cord inflammation and the involvement of the vein (phlebitis), the involvement of one or both arteries (arteritis), and the presence of inflammation of the Wharton's jelly. Umbilical cord plasma interleukin-6 concentrations were assayed by a sensitive and specific immunoassay.

RESULTS

Neonates with umbilical arteritis had a significantly higher median concentration of cord plasma interleukin-6 (median, 111 pg/mL; range, 0.1-19,230 pg/mL) than those without umbilical arteritis (median, 22.5 pg/mL; range, 0.9-511.6 pg/mL; P <.05). Also, severe neonatal morbidity occurred more frequently in infants with arteritis than in those without arteritis (74% vs 50%; P <.05). And finally, the most severe form of inflammation, which involves both arteries, vein, and Wharton's jelly, was associated with the highest median concentration of plasma interleukin-6 observed in this study (median, 182.6 pg/mL; range, 0.1-7,400 pg/mL), whereas inflammation limited to the vein (phlebitis) was associated with a lower concentration of cord plasma interleukin-6 (median, 29.1 pg/mL; range, 0.9-511.6 pg/mL; P <.05).

CONCLUSION

Neonates whose placenta demonstrates umbilical arteritis have higher concentrations of umbilical cord plasma interleukin-6 and higher rates of adverse outcome than those without umbilical arteritis.

Prenatal development of the human mandible

In an effort to better understand the interrelationship of the growth and development pattern of the mandible and condyle, a sequential growth pattern of human mandibles in 38 embryos and 111 fetuses were examined by serial histological sections and soft X-ray views. The basic growth pattern of the mandibular body and condyle appeared in week 7 of fertilization. Histologically, the embryonal mandible originated from primary intramembranous ossification in the fibrous mesenchymal tissue around the Meckel cartilage. From this initial ossification, the ramifying trabecular bones developed forward, backward and upward, to form the symphysis, mandibular body, and coronoid process, respectively. We named this initial ossification site of embryonal mandible as the mandibular primary growth center (MdPGC). During week 8 of fertilization, the trabecular bone of the mandibular body grew rapidly to form muscular attachments to the masseter, temporalis, and pterygoid muscles. The mandible was then rapidly separated from the Meckel cartilage and formed a condyle blastema at the posterior end of linear mandibular trabeculae. The condyle blastema, attached to the upper part of pterygoid muscle, grew backward and upward and concurrent endochondral ossification resulted in the formation of the condyle. From week 14 of fertilization, the growth of conical structure of condyle became apparent on histological and radiological examinations. The mandibular body showed a conspicuous radiating trabecular growth pattern centered at the MdPGC, located around the apical area of deciduous first molar. The condyle growth showed characteristic conical structure and abundant hematopoietic tissue in the marrow. The growth of the proximal end of condyle was also approximated to the MdPGC on radiograms. Taken together, we hypothesized that the MdPGC has an important morphogenetic affect for the development of the human mandible, providing a growth center for the trabecular bone of mandibular body and also indicating the initial growth of endochondral ossification of the condyle.

Acute funisitis of preterm but not term placentas is associated with severe fetal inflammatory response

Acute funisitis, whose basic pathologic feature is umbilical vasculitis, constitutes a type of fetal inflammatory response to intrauterine infection. In the present study, a comparative analysis was performed between the clinicopathologic profiles of acute funisitis in term and preterm placentas along with measurement of fetal plasma interleukin 6 (IL-6) levels by specific immunoassay to assess the different biologic implications for the fetus. Acute funisitis in preterm placentas showed a significantly higher incidence of umbilical arteritis (P <.000001), higher fetal plasma IL-6 level (P <.0001), and higher prevalence of major perinatal morbidities (P <.0001). To assess the possible variation in fetal cell response to infectious agents according to gestational age, amnion cells and placental villous tissues obtained at different gestational ages were treated with bacterial lipopolysaccharides, and the IL-6 level of the culture media was assayed. Amnion cells and placental villous tissues from preterm placenta showed a more pronounced cytokine response than those from term placenta. The findings of this study indicate that the clinicopathologic significance of acute funisitis in term placentas is different from that of preterm placentas. Furthermore, they indicate that the robust inflammatory response of the fetus associated with elevated fetal plasma IL-6 level may reflect the biologic needs of the premature fetus to escape from the hostile intrauterine environment.

CD99 immunoreactivity in ependymoma

The expression of CD99 in normal ependymal cells and ependymoma has been reported. However, only limited numbers of tumors have been studied, and the pattern of CD99 expression has not been described. The authors' purpose was to investigate CD99 immunoreactivity in ependymoma and its use for differential diagnosis. Twenty-five ependymomas were immunostained with antibody directed at CD99. The result of immunostaining of ependymomas was compared with 63 nonependymal tumors that histologically resemble ependymal neoplasms. The nonependymal tumors included 19 astrocytic tumors, 6 oligodendroglial tumors, 8 choroid plexus neoplasms, 2 central neurocytomas, 5 medulloblastomas, 10 primitive neuroectodermal tumors (PNET), and 13 pituitary adenomas. All ependymomas showed strong expression of CD99 in membranous pattern with intracytoplasmic or intercellular dots (ICDs). The expression pattern of CD99 was not correlated with histologic type or grade of ependymomas. Among 63 nonependymal tumors, 11 (17.5%) showed incomplete membrane staining for CD99; diffuse in 4 PNETs and focal in 5 choroid plexus neoplasms (3 papillomas and 2 carcinomas) and one each of pituitary adenoma and oligodendroglioma. The ICD was not found in nonependymal tumors except a case of choroid plexus papilloma. However, membrane staining or ICD for CD99 was not distinctive in nonependymal tumors. In conclusion, the characteristic pattern of anti-CD99 antibody, i.e., diffuse strong membranous immunostaining with ICDs, is useful in distinguishing ependymomas from the central nervous system tumors that histologically mimic ependymoma.

Congenital monoblastic leukemia with 9;11 translocation in monozygotic twins : a case report

We report an autopsy case of congenital monoblastic leukemia that developed in monozygotic twins. The twin presented with progressive hepatosplenomegaly at 4 weeks after birth. One twin died of massive bleeding and hypovolemic shock before the treatment started. At autopsy, the liver was diffusely enlarged and showed a diffuse whitish discoloration except for the subcapsular and perivenular areas. Microscopic examination disclosed infiltration of histiocyte-like atypical cells along the sinusoids and portal areas of the liver. Spleen, lymph nodes and choroid plexus were also infiltrated by the tumor cells. However, bone marrow involvement of the tumor was minimal although multifocal. On immunohistochemical staining, these atypical cells were reactive for CD68 (PGM-1) and lysozyme, suggesting that the tumor cells might have been derived from mono- histiocyte. Cytogenetic study revealed 9;11 translocation, which is frequently associated with acute monoblastic leukemia. To the best of our knowledge, this is the first report of congenital monoblastic leukemia of monozygotic twins in Korea.

Gangliocytoma of the spinal cord: a case report

We present a case of intramedullary spinal gangliocytoma in a 7-year-old girl who presented with scoliosis and progressive weakness of both legs. The tumour involved the whole spinal cord and medulla oblongata and was composed of inner cystic and outer solid components. On MRI, the solid portion of the lesion showed strong enhancement at the thoracolumbar level and mild enhancement at the cervical and medullary levels. Histological examination of the surgical specimen showed neoplastic ganglion cells arranged irregularly in benign normocellular glial background, which made a diagnosis of gangliocytoma.

Biological behavior and tumorigenesis of subependymal giant cell astrocytomas

In spite of the benign nature of subependymal giant cell astrocytomas (SEGAs), some show massive hemorrhage, rapid growth, and tumor recurrence. This led us to investigate the biological behavior, cell dynamics, and tumorigenesis of SEGAs. All patients (4 men and 3 women; age range, 6-27 years; mean, 13.6 years) had features of tuberous sclerosis complex and obstructive hydrocephalus. One patient had intratumoral bleeding. In two patients, sequential neuroimaging showed a subependymal nodule growing to become a SEGA. All underwent surgical resection without radiation therapy. One tumor recurred and was treated surgically. There were no postoperative deaths. The presence of cytologic atypia, mitoses and vascular proliferation had no implication in terms of the clinical course. MIB-1 labeling indices were low (mean, 0.9), indicating low proliferative potential. Unexpectedly, bcl-2 staining was sparse and bax staining predominated in majority of cases. However, the mean value of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling index was low. Immunohistochemically, tumors were positive for both glial and neuronal markers. In the majority of our cases, the expression of p53 was low. Only one tumor was focally positive for tuberin. SEGAs have low proliferative potential and apoptotic activity, and exhibit features of mixed glial-neuronal differentiation. In contrast to p53, tuberin is suggested to be the tumor suppressor in this tumor.

A histomorphometric study of corneal endothelial cells in normal human fetuses

The purpose of this study was to investigate the histomorphometric change in the normal development of human fetal corneal endothelial cells. Eighty one human fetal corneas, ranging from 12 to 40 weeks of gestation, were examined. For determination of gross parameters, corneal diameter and height were measured. Then the corneal endothelium including Descemet's membrane was stained with hematoxylin-eosin using a flat preparation method. In addition to histologic examination under the light microscope, computer-assisted image analysis was performed to determine the cell area, coefficient of variation in cell area and cell density, in both central and peripheral cornea, from each specimen. Total cell count per cornea was obtained by multiplying endothelial cell density by corneal surface area. Linear and nonlinear regression analysis of gestational age and each parameter were used to model corneal endothelial development during the prenatal period. Fetal cornea grows rapidly throughout the prenatal period. During the same period, mean cell area and total cell count also increases gradually, but there is a steep increase in the total cell count in the early period and of the cell area in the late period. The mean cell density decreases rapidly from 16 015 to 6167 cell x mm(-2). There was no significant difference in all parameters except cell density, between the central and peripheral cornea and the difference in cell density was only 2%. In the early prenatal period, there is a rapid increase of total cell count by mitosis, whereas in the late period enlarged endothelial cells cover the rapidly widening inner corneal surface without a significant change in the total cell count.

Prevalence of Gs alpha mutations in Korean patients with pituitary adenomas

The reported frequencies of Gs alpha mutations (gsp mutations) in growth hormone (GH)-secreting pituitary adenomas are variable (ranging from 4.4 to 43%), and the presence of these mutations in the other pituitary adenomas is still a matter of controversy. Previous clinical and biochemical analyses of patients with GH-secreting pituitary adenomas and gsp mutations produced conflicting results and did not demonstrate obvious characteristics. Therefore, we investigated the prevalence of gsp mutations in Korean patients with pituitary adenomas and elucidated the characteristics of these patients. Forty-four GH-secreting adenomas, 7 prolactin (PRL)-secreting adenomas and 32 clinically non-functioning adenomas were examined for the presence of point mutations in codon 201 and 227 of the Gs alpha gene using a nested PCR and direct sequencing of DNA extracted from fresh tissue or paraffin-embedded pituitary adenoma samples. Seven of the 44 GH-secreting pituitary adenomas had point mutations at codon 201 or 227; of these, five mutations were in codon 201 and two were in codon 227. In patients with gsp mutations, mean tumor size was significantly smaller than in patients without gsp mutations (15.9+/-8.7 mm vs. 24.9+/-14.9 mm, P<0.05). Age, sex, basal GH levels, GH response to oral glucose loading, GH response to octreotide and surgical outcome were not different in the two groups. One of the 32 clinically non-functioning pituitary adenomas had a point mutation at codon 201; none of the seven prolactinomas had these mutations. These results show that gsp mutations are not rare in Korean acromegalic patients and mean tumor size is significantly smaller in acromegalic patients with gsp mutations. Our results also confirm the low frequency of gsp mutations in clinically non-functioning pituitary adenomas and the absence of gsp mutations in prolactinoma.

Chordoid meningioma with polyclonal gammopathy. Case report

The authors present a case of chordoid meningioma in a 55-year-old woman who manifested headache and personality change. Magnetic resonance imaging of the brain and cerebral angiography demonstrated a mass in the right frontal lobe that resembled a typical convexity meningioma. However, the pathological diagnosis was chordoid meningioma, a rare subtype of this tumor that usually occurs in adolescence and is known to be associated with Castleman syndrome. A meningothelial meningiomatous pattern suggestive of a meningothelial origin was focally present, and cytokeratin-positive squamoid cells were noted in the tumor. The lesion lacked dense infiltration of lymphocytes and plasma cells. Polyclonal gammopathy was the only sign of Castleman syndrome and hypochromic microcytic anemia was absent in this case. Polyclonal gammopathy resolved completely 6 months after total removal of the mass.

The detection of p53 gene mutation using a microdissection technique in primary intracranial germ cell tumors

Using a microdissection technique, the contribution of the p53 mutation to tumorigenesis and prognosis in each histological subtype of the intracranial germ cell tumors (GCTs) was evaluated. Nineteen patients had primary intracranial GCTs, including 4 germinomas (GEs), 4 teratomas (TEs), 1 mixed tumor of GE and TE, and 10 mixed GCTs containing non-germinomatous malignant germ cell tumors (NG-MGCTs). After microdissection of specific subtypes, genomic DNA was screened for mutations in exons 5-8 of the p53 gene, using the dideoxyfingerprinting (ddF) followed by direct DNA sequencing. The direct sequencing revealed a total of six mutations in PCR products derived from the five cases (26%) which showed mobility shifts in ddF. Among the six mutations detected, four were missense mutations and two were silent. Missense mutations of the p53 gene tended to occur more frequently in the NG-MGCT component than in the GE or TE components (3/15 vs. 1/12 vs. 0/13). The incidence of missense mutations was not different between the survivors (3/13) and the deceased (1/6). This study suggests the possible role of the p53 gene in the tumori-genesis of NG-MGCT. However, p53 gene mutation did not correlate with the prognosis of NG-MGCT.

Transient expression of transglutaminase C during prenatal development of human muscles

Tissue transglutaminase (TGase C, TGase II) is known to participate in cellular processes during morphogenesis, differentiation, and development of various prenatal tissues and organs. The expression of TGase C during myoblast proliferation and attachment to external laminae was examined by immunohistochemical (IH) localization at 5-12 weeks of developmental stages of prenatal human muscle in 23 embryos. IH detection using a monospecific antibody to TGase C showed a prominent expression of TGase C in muscle cells as stage- and spatial-specific patterns during an early embryonal period. The myoblasts of intervertebral, tongue, and limb muscles, attached to adjacent cartilaginous skeletons or fibrous fascia, showed a pronounced expression of TGase C at 5-6, 6-7, and 7-8 weeks after fertilization, respectively. The most intense activity of TGase C was observed in some cardiac myoblasts infiltrating into endocardial mesenchyme at 6-7 weeks after fertilization. Although weak staining was detected until 14 weeks after fertilization, the level of TGase C expression in all muscles was significantly decreased after 6-7 weeks, with the exception that the smooth muscle cells of blood vessels and gastrointestinal tract showed diffusely intense staining of TGase C between 5 and 12 weeks after fertilization. Western blotting analysis of the cellular extracts of pooled samples showed a single strong band at 80 kD at 6 weeks after fertilization. This band became weaker after 8-10 weeks of prenatal development. These findings of transient expression of TGase C, which coincides with the development of myoblast anchoring and differentiation, suggest that TGase C plays a role in myoblast attachment to the extracellular laminae during the early embryonal period.

Achondrogenesis type II (Langer-Saldino achondrogenesis): a case report

Achondrogenesis is a lethal form of congenital chondrodystrophy characterized by extreme micromelia. We describe a case of achondrogenesis type II (Langer-Saldino achondrogenesis) detected by prenatal ultrasonography at 20-week gestation. A dwarfed fetus with large head, short neck and chest, prominent abdomen and short limbs was terminated transvaginally. Radiologic and histopathologic examination revealed features of mild form of achondrogenesis type II. Although the case had no known risk factor and the phenotypic abnormality was mild, modern development in prenatal screening made the early detection possible.

Clinicopathologic study of Castleman's disease in Korea

Castleman's disease represents an atypical lymphoproliferative disorder, infrequently associated with various immunologic abnormalities or subsequent development of malignancy such as Kaposi sarcoma, malignant lymphoma and plasmacytoma. Its clinicopathologic features depend on various etiologic factors such as Kaposi sarcoma herpesvirus (KSHV), oversecretion of IL-6, adhesion molecule and follicular dendritic cell dysplasia, etc. To investigate the relationship of Castleman's disease (CD) and the above factors, we reviewed 22 cases of CD. Four cases of KSHV positive CD were detected, all multicentric, plasma cell type, and these cases displayed prominent vascular proliferation, characteristic 'Kaposi-like lesion'. IL-6 and CD54 positive mononuclear cells were scattered in interfollicular areas of KSHV positive cases. Follicular dendritic cell hyperplasia, vascular proliferation, expression of IL-6 and CD54 did not show any significant difference between solitary vs multicentric type, and plasma cell type vs hyaline vascular type. Our study suggests that KSHV positive CD reveals unique pathologic features, and the probable relationship of KSHV and IL-6 and CD54 is discussed.

The effect of isochromosome 17q presence, proliferative and apoptotic indices, expression of c-erbB-2, bcl-2 and p53 proteins on the prognosis of medulloblastoma

Medulloblastoma accounts for 20 to 25% of all intracranial neoplasms in children. The significance of the presence of isochromosome 17q (i(17q)), proliferative potential, apoptotic activity, and expression of c-erbB-2, bd-2, and p53 proteins in predicting long-term survival of patients with medulloblastomas was investigated. Twenty children were divided into two groups (favorable and poor outcome groups). Ten children with favorable outcome (FO) were disease-free during the follow-up period (median: 61.5 months). The other ten children with poor outcome (PO) died of disease progression, having a median survival of 18 months. Fluorescent in situ hybridization (FISH) for i(17q), terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL), and immunohistochemistry for Ki-67, c-erbB-2, bcl-2, and p53 proteins was performed in these patients. Nine out of 17 children showed i(17q). There was no difference in the rate of positive i(17q) between the FO and PO groups. The presence of i(17q) was not significantly related to biological factors that we investigated. Unlike the prominent presence of the proliferative potential and p53 expression in children with PO, apoptotic activity and expression of c-erbB-2 and bcl-2 had no correlation with the outcome.

Dysembryoplastic neuroepithelial tumor: radiological findings (including PET, SPECT, and MRS) and surgical strategy

In order to elucidate the radiological features of dysembryoplastic neuroepithelial tumor (DNT), and to clarify the optimal surgical strategy for this tumor, the authors retrospectively analyzed 20 cases of DNT treated at our institution. Magnetic resonance (MR) imaging (all cases), 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) (eight cases), ictal/interictal Tc99m-HMPAO single photon emission computed tomography (SPECT) (seven and five cases respectively) and proton magnetic resonance spectroscopy (1H MRS) (one case) were performed preoperatively. Invasive monitoring/intraoperative electrocorticography (ECoG) was performed in four cases in order to determine the epileptogenic zone. A well-demarcated lobulating tumor located in the cortical with/without subcortical area was the typical MR finding. 18F-FDG PET showed glucose hypometabolism in all cases. Ictal Tc99m-HMPAO SPECT showed hyperperfusion of the lesion in three cases and interictal Tc99m-HMPAO SPECT showed hypoperfusion of the lesion in one case. 1H MRS showed nonspecific findings. Gross total resection was performed in all cases. Histologically, associated cortical dysplasia was found in 11 cases. The mean duration of follow-up after surgery was 37.9 months, and the overall seizure free rate was 90%. Follow-up MR imaging was performed in 14 cases (mean duration of follow-up: 21.6 months) and showed no recurrence of tumor in any of these cases. Invasive monitoring/intraoperative ECoG and the presence of cortical dysplasia showed no significant relationship with seizure control rate (p = 1.25 and p = 1.62 respectively).

Combined anomaly of intramedullary arteriovenous malformation and lipomyelomeningocele

We report a rare situation in which a lipomyelomeningocele and an intramedullary arteriovenous malformation (AVM) occurred together at the T11-L1 level in a 44-year-old man. MR images showed a hypervascular lesion intradurally and a fatty component extradurally. Spinal angiography revealed this lesion to be an intramedullary AVM with multiple feeding arteries from the right T12 and left T10 intercostal artery and the left L1 lumbar artery, drained by tortuous, dilated, perimedullary veins.

The effect of regular salbutamol on lung function and bronchial responsiveness in patients with primary ciliary dyskinesia

STUDY OBJECTIVE

There is growing evidence that regular beta(2)-agonist use in patients with asthma is associated with decreased airway caliber and increased bronchial responsiveness. The aim of this study was to determine whether regular treatment with beta(2)-agonists induces changes in lung function and bronchial responsiveness in patients with primary ciliary dyskinesia.

DESIGN

A randomized, double-blind, placebo-controlled, crossover study.

PATIENTS

Nineteen children with primary ciliary dyskinesia.

INTERVENTIONS

Subjects received inhaled salbutamol or identical placebo (2 x 100 microg qid) for periods of 6 weeks with a wash-out period of 4 weeks.

MEASUREMENTS AND RESULTS

FEV(1) was measured before and 3 weeks and 6 weeks after salbutamol or placebo treatment. High-dose methacholine inhalation tests were performed before and 6 weeks after each treatment. The provocative concentration of methacholine producing a 20% fall in FEV(1) (PC(20)) and maximal airway narrowing (MDeltaFFEV(1)) was measured. No significant change in FEV(1) was observed during the salbutamol or placebo periods. No significant differences in the parameters of bronchial responsiveness (PC(20) and MDeltaFFEV(1)) were noted as the result of either salbutamol or placebo treatment.

CONCLUSION

Our data have shown that salbutamol, inhaled regularly for 6 weeks, did not cause either a decline in lung function or an increase in bronchial responsiveness in subjects with primary ciliary dyskinesia.