Search PubMed⌕ Search

Biomedical subjects

B K Cho

Publications and source records attributed to B K Cho.

At least 109 records · Page 6Linked to original sources
PubMed1997

Complications of pediatric craniofacial surgery in the Orient: analysis of a 10-year experience.

Numerous reports on the complications of craniofacial surgery have been published in the western world. However, relatively little such information concerning Oriental populations has been documented. We therefore set out to provide a retrospective analysis of all the complications of craniofacial surgery encountered during the 10-year period of 1986 to 1995 at Seoul National University Children's Hospital, the only children's hospital in Korea. Forty-nine children underwent 57 consecutive craniofacial procedures at our institution during 1986 to 1995. A retrospective chart analysis of the frequency and types of complications was performed. Mantel-Haenszel chi-square tests were then calculated for several factors, including age at surgery, duration of surgery, intraoperative losses of hemoglobin and hematocrit, total amount of blood transfusion, and the number of complications according to year, diagnosis, and operative procedure to find any significant correlation with the incidence of complications. Mortality was 1.8%. The major complication rate was 7.0% and included cases of visual loss and persistent cerebrospinal fluid leak. Analysis revealed the presence of several trends, including an increased incidence of complications with increased patient age at surgery, duration of surgery, and intraoperative loss of hematocrit. The number of complications was also noted to increase in cases with complex craniofacial synostosis syndromes (Crouzon's, Apert's Antley-Bixler, etc.) and tumors of the orbit and cranium. Finally, complications were noted to decrease in recent years, most likely due to the increased experience of our craniofacial team. Nevertheless, statistical analysis revealed that the incidence of complications correlated significantly only with increased duration of surgery (p < 0.05). The results of our study indicate that although craniofacial surgery in the Orient carries an inherent risk for significant complications, the risk can be minimized and the rate of mortality and major complications kept to an acceptable level by a careful and experienced craniofacial team. Groups at most risk for complications are those with a long duration of surgery.

Adolescent↗
PubMed1997

Milia en plaque associated with pseudoxanthoma elasticum.

We report a woman with numerous milia occurring in a plaque-type distribution in the postauricular area, who has suffered from cutaneous pseudoxanthoma elasticum on both sides of the neck. Milia may arise primarily or may follow a number of dermatoses. We believe this is a unique case because milia en plaque coexisting with pseudoxanthoma elasticum does not appear to have been reported previously.

Adult↗
PubMed1997

Cerebral sparganosis in a child.

Cerebral sparganosis in childhood is very rare. Until 1996, 2 cases in children up to 15 years of age had been described. We report a case of cerebral sparganosis in a 6-year-old girl who presented with seizures. Sequential brain magnetic resonance imaging scans spaced over 4 months showed a lesion which migrated from the right parieto-occipital region to the right occipital region. The enzyme-linked immunosorbent assay for antisparganum antibody was positive. She most likely contracted sparganosis from worm-infested spring-water. A live worm with surrounding granulomatous tissue was removed, and the enzyme-linked immunosorbent assay for antisparganum antibody converted to negative 12 months following surgery. In areas of endemic sparganosis, the possibility of cerebral sparganosis should be considered, even in a child, if the patient shows a migrating granulomatous lesion.

Brain Diseases↗
PubMed1997

Histopathological findings, viral DNA distribution and lymphocytic immunophenotypes in vesicular and papular types of herpes zoster.

The characteristics rash of herpes zoster begins as erythematous macules and papules, progressing to vesicles within 12-24 h. Patients with persistent papules without vesicular change are occasionally found. Our aim was to elucidate differences in vesicular and papular types of herpes zoster. Biopsy specimens from 21 patients were examined by an in situ hybridization method to observe viral distribution, and lymphocytic immunophenotypes were evaluated immunohistochemically. There was no differences in cell-mediated immunity or immunophenotypes in lymphocytic infiltrates between vesicular and papular types of herpes zoster. DNA of varicella-zoster virus was detected in the epidermis and hair follicles in the vesicular type but was found in the pilosebaceous unit in the papular type. This indicates that the appearance of clinical types of herpes zoster depends on the infected site of varicella-zoster virus in the tissue.

Adolescent↗
PubMed1997

Choroid plexus carcinoma in an infant.

Choroid plexus carcinoma is a rare tumor and has a strong tendency to spread along the cerebrospinal fluid pathway. The tumor frequently occurs in infants. Radiation therapy is not indicated in infants and the response of this tumor to chemotherapy is variable. Therefore, surgical removal plays a major role in the management of this tumor, especially in infants. A 2-month-old girl with an acute communicating hydrocephalus was presented. Through the left posterior parietal transcortical approach, a choroid plexus carcinoma which had poor demarcation from the posterior thalamus and the medial wall of the lateral ventricle was subtotally (> 95%) removed. Postoperatively a ventriculoperitoneal shunt was inserted. Chemotherapy was refused. Magnetic resonance imaging taken at 11 months after surgery showed multiple intracranial seeding of the tumor. She was in a bed-ridden state. This case revealed the aggressive behaviour of choroid plexus carcinoma in an infant and the dismal result of subtotal removal alone, though it is rather radical.

Choroid Plexus Neoplasms↗
PubMed1997

Cerebral leiomyoma in a child.

A case of primary cerebral leiomyoma in a 12 year-old boy with unique clinical features is described. He presented with fever, and the magnetic resonance imaging demonstrated a well demarcated mass in the subcortical white matter of the right temporal lobe. The mass showed low signal intensity on T1-weighted images and high signal intensity on T2-weighted images with a strong homogeneous gadolinium-DTPA enhancement. The mass was removed in toto and was composed of fasciculating, monotonous oval to spindle cells which had both immunohistochemical and ultrastructural features of primitive smooth muscle differentiation. The patient is free of recurrence during the follow-up period of 56 months. Detailed clinicopathologic findings are discussed.

Brain Neoplasms↗
PubMed1997

Hemodynamics of the total cavopulmonary connection: an in vitro study.

To understand the local fluid dynamics for different designs of Fontan operation, five models were made of Pyrex glass to facilitate in vitro study. Models I, II and III had the same position as the center of the anastomosis of the IVC (inferior vena cava) with that of the SVC (superior vena cava), but Models IV and V had 10 mm offset between them. As well, the anastomotic junction angles were different (Models I and IV: 90 degrees, Models II and V: 70 degrees, Model III: 45 degrees). These models were then connected to a flow loop for flow visualization study. In Model I, no dominant vortex was seen in the central region of the junction, but a large unstable vortex was created in Models II and III. In Models IV and V, a significant stagnation region was created in the middle of the offset region. It also showed that the flow distribution from the IVC and SVC to the LPA (left pulmonary artery) and RPA (right pulmonary artery) depends more on the offset of the junction than on the anastomotic junction angle. Generally, as the total flow rates increased, the pressures in the models increased.

Blood Pressure↗
PubMed1997

Design of a medical image processing software for clinical-PACS.

Software modules for interactive display, manipulation and retrieval of medical images have been designed for a Picture Archiving and Communications System (PACS). The target of these modules is not for a high-end diagnostic workstation for radiologists, but for a PC-based low cost clinical workstation for a referring physician. This software is constructed based on a concept of an object-oriented language which is designed to be modular and expandable. It consists of several functional modules: (a) a communication module for image retrieval, (b) a standard module for the interpretation of the DICOM images, (c) a user interface module for the non-computer oriented clinicians and (d) a tool module for viewing and manipulating images as well as editing the annotation.

Image Processing, Computer-Assisted↗
PubMed1996

Primary intramedullary spinal cord primitive neuroectodermal tumor with intracranial seeding in an infant.

Primary spinal cord primitive neuroectodermal tumor (PNET) is a rare entity. In all 13 cases have been reported in the literature, including 3 with intracranial seeding. A 3-month-old girl with involvement of the spinal cord below the mid-thoracic level is described. The brain MRI revealed findings indicative of seeding along the intracranial subarachnoid space. Biopsy, duraplasty and removal of laminotomy flap were done. In spite of a good response to the first cycle of postoperative "8-drugs-in-a-day' chemotherapy, further treatment was refused. She died 21 days after the onset of leg weakness, which reveals the rapid progression of untreated cases. To our knowledge, this is the first case of spinal cord PNET with parenchymal involvement that has been described in an infant.

Fatal Outcome↗
PubMed1996

A case of Cobb syndrome associated with lymphangioma circumscriptum.

Cobb syndrome describes the association of a spinal angioma and a cutaneous angioma such as nevus flammeus or angiokeratoma of the corresponding dermatome. A 23-year-old Korean female showed spiral cord angiomas and segmentally distributed nevus flammeus of corresponding dermatomes (Th5-Th2). Interestingly she had a lymphangioma circumscriptum in the same dermatomes. To the best of our knowledge, there is no report of this constellation. Therefore, we suggest that lymphangioma circumscriptum may be considered as a skin finding of Cobb syndrome.

Adult↗
PubMed1996

Terminal myelocystocele--a case report.

Terminal myelocystocele is a rare form of occult spinal dysraphism in which the hydromyelic caudal spinal cord and the subarachnoid space are hemiated through a posterior spina bifida. A 1.5 month old boy presented with a large lumbosacral mass and urinary incontinence. The magnetic resonance imaging, operative findings and pathological findings revealed a low lying conus with a dilated central canal dorsally attached to the subcutaneous tissue. Ventral subarachnoid space was enlarged and herniated through the laminar defect of the sacrum. The lesion was typical of a terminal myelocystocele. The clinical features are different from those of myelomeningocele in many aspects. Though the incidence is low, terminal myelocystocele should be included in the differential diagnosis of congenital lesions presenting as a lumbosacral mass.

Arachnoid↗
PubMed1996

Experimentally induced Chiari-like malformation with myeloschisis in chick embryos.

Though several pathogenetic theories concerning the frequent association of Chiari malformation and hydrocephalus with myeloschisis have been suggested, none of them explains all the aspects of the disorder. To investigate whether myeloschisis is the direct cause of Chiari malformation and hydrocephalus or these conditions are the results of another basic event, we observed the morphological changes of the posterior cranial fossa and its components in the chick embryos with surgically induced myeloschisis. To make myeloschistic lesions, we opened the neural tube for a length of 9-11 somites in Hamburger and Hamilton stage 16-19 chick embryos. They were divided into cervicothoracic (C-T) and lumbosacral(L-S) groups according to the area of incision. The embryos were re-incubated until postoperative day 11. In the control group, embryos were incubated with the eggshell window open as their experimental counterparts. The survival rates of each group were as follows; 11% (9 survivors/85 operated embryos), 8% (7/83), and 17% (10/60) in the C-T, L-S and control groups, respectively. Myeloschisis positive rates were 100% in the operated groups and 0% in the control group. The heads of embryos were sectioned along the sagittal plane to observe the morphological changes in the posterior cranial fossa and its components. Of the survivors, five in the C-T group, two in the L-S group and six in the control group were available for light microscopic inspection. In the majority of embryos with myeloschisis, without difference between the C-T and L-S groups, the fourth ventricles were smaller than those of the control group and the subarachnoid spaces in the posterior cranial fossa were also narrower. In embryos with severe changes, the cerebellum displaced downward comparing with that of the control embryos. No evidence of hydrocephalus was present Though not always typical, morphological changes similar to Chiari malformation were observed in chick embryos with surgically induced myeloschisis. It suggests a strong direct causal relationship between the two conditions and supports the theories of derangements in cerebrospinal fluid dynamics rather than those of primary mesenchymal or neural origin as a pathogenetic mechanism of Chiari malformation.

Animals↗
PubMed1996

[Mite infestation rate of pet dogs with ear dermatoses].

This study aimed to investigate the incidence of the canine ear dermatoses caused by mites and the relativity of the causative mites of canine dermatoses to the pruritic dermatoses of the families possessing the pet dogs. Total 970 samples were collected from the lesional hairs and scales of the ear of pet dogs referred to Chung-Woon animal clinic in Seoul from January, 1990 to December, 1995. The mites were collected from the samples by means of the washing method. Presence of pruritic dermatoses in the families possessing the pet dog was evaluated. Among 2,147 mites collected from 970 samples, 2,117 specimens were Octodectes cynotis and others were Sarcoptes canis (30 mites). O. cynotis were found in 382 samples out of total 970 samples (39.4%) and S. canis were found in 3 samples (0.3%). Although two families out of 382 families that possessed the diseased pet dog by O. cynotis had the family histories of pruritic dermatoses, their pruritic dermatoses were not related to the infestation by O. cynotis. In conclusion, O. cynotis, the most common canine mite producing pruritic ear dermatoses, does not cause pruritic dermatoses in man.

Animals↗
PubMed1996

Post-exercise response of ventricular ejection fraction after total repair of congenital heart disease with left to right shunt.

A radioisotope first pass study was done on patients over a period of 1 to 15 years (average 4.6 years) after repair for ventricular septal defect or arterial septal defect with a left to right shunt. The age of the patients ranged from 6 to 32 years (average 14.2 year) at the time of the study. The total work of exercise and the right and left ventricular ejection fraction(EF) were evaluated at rest and after exercise. The results were compared with the preoperative hemodynamic findings and with the age of patient at the time of the operation. 1) When the total work of exercise was divided with the maximal exercise capacity of the normal individual corresponding to the patients' height and body surface area (the percentage of total work), it were very low with the average of 40% of normal. There was no sexual difference, but the percentage of total work of exercise had significant correlation with the patients' age at the time of operation (r = -0.52, p < 0.01) and post-exercise left ventricular ejection fraction (LVEF)(r = -0.39, p < 0.05). 2) LVEF at rest had some correlation with the preoperative mean pulmonary arterial pressure (r = -0.29, p = 0.05), but showed no relationship with Qp/Qs or Rp/Rs ratios. The right ventricular ejection fraction (RVEF) at rest had no relations with the preoperative hemodynamic findings with maximal workload. 3) The post-exercise RVEF showed linear correlation with the preoperative Rp/Rs ratio (r = -0.49, p < 0.005), and mean pulmonary arterial pressure (r = -0.37, p < 0.05). The post-exercise LVEF had no significant correlation with any preoperative hemodynamic factors. 4) When greater than 5% increase in ventricular EF after exercise is considered normal, the group with the normal right and left ventricular responses (n = 11) showed normal preoperative Rp/Rs ratio (7.6 +/- 4.1). In the group with normal left, but abnormal right ventricular response (n = 9) and the group with abnormal biventricular response (n = 11), both demonstrated incremental increase in Rp/Rs ratio (20.1 +/- 11.3, 26.3 +/- 19.8 respectively). Normal right, but abnormal left ventricular reaction (n = 2) was noted in patients with residual aortic valvular insufficiency and residual ventricular septal defect. In conclusion, post-operative ventricular response was much more sensitive and informative than that of ventricular function at rest and to detect subclinical cardiac dysfunction. Post-exercise RVEF was closely correlated with preoperative pulmonary vascular hemodynamics, while post-exercise LVEF seemed to be a major determinant of working capacity after repair.

Adolescent↗
PubMed1996

Serum levels of antioxidant vitamins in relation to coronary artery disease: a case control study of Koreans.

With the changes in trends of disease pattern from infectious to chronic degenerative disease, cardiovascular disease has been considered as the major cause of death in Korea. Numerous studies have been done on the antioxidant effects of some vitamins in the prevention of chronic illness, but not many in relation to the cardiovascular disease. Therefore, the relation between antioxidant vitamins, mainly alpha-tocopherol (alpha-T) and beta-carotene (beta-C), and coronary artery disease (CAD) such as angina pectoris and myocardial infarction has been investigated in this study. The blood samples were obtained from the CAD patients who were angiographically diagnosed within a month (100 case group). Patients who had an experience of PTCA or CABG were excluded from the study. Control subjects were healthy adults who had normal EKG values, no chest pain and no past history of cardiac disease (100 control group). All subjects were free for serum lipid lowering drugs. Serum alpha-T and beta-C were analysed using HPLC. In addition to antioxidant vitamins, serum lipids (total cholesterol, HDL, TG) were also measured. Each case and control was matched in terms of age and sex. And all the CAD risk factors such as blood pressure, smoking, alcohol, serum lipid profile and BMI were adjusted to determine pure effect(s) of alpha-T and beta-C on the CAD. The concentrations of both alpha-T and beta-C were significantly lower in the CAD group than those in control group (P < 0.05); in CAD group, mean values of alpha-T and beta-C were 11.9 +/- 7.2 (micrograms/ml), 35.8 +/- 3.1 (micrograms/dl) respectively. As for the levels of beta-C, it shows inverse relation with age, but not for the alpha-T levels. Serum levels of both vitamins did not show any significant differences in terms of sex, but men have a tendency o higher levels of beta-C, but lower levels of alpha-T.

Adult↗
PubMed1995

Characterization of a single-chain antibody to the beta-chain of the T cell receptor.

In this report the VH and VL genes of the anti-T cell receptor (TCR) antibody KJ16, which recognizes the TCR V beta 8.1 and V beta 8.2 regions in mice, were cloned and expressed as a single-chain antibody (scFv) in Escherichia coli. A 29-kDa protein was obtained after renaturation from inclusion bodies. The KJ16 scFv had a relative affinity for the native TCR that was slightly higher than KJ16 Fab fragments. The scFv and Fab fragments of the KJ16 antibody, together with monovalent forms of two other anti-TCR antibodies, were evaluated as antagonists of the T cell-mediated recognition of a peptide-class I complex or of a superantigen, Staphylococcus enterotoxin B (SEB) bound to a class II product. Each of the anti-TCR antibodies was efficient at inhibiting the recognition of the SEB-class II complex. In contrast, only the clonotypic antibody, which binds to epitopes on both V beta and V alpha regions, inhibited the recognition of peptide-class I complex. We conclude that the TCR binding site for the SEB-class II ligand encompasses a larger surface area than the TCR binding site for the peptide-class I ligand.

Amino Acid Sequence↗