Biomedical subjects

Ken R Winston

Publications and source records attributed to Ken R Winston.

6 recordsLinked to original sources

PubMed2006

CSF shunt failure with stable normal ventricular size.

OBJECTIVE: The purpose of this study was to review the clinical features of a group of patients in whom ventricular enlargement was not a manifestation of prolonged CSF shunt obstruction. RESULTS: Twelve patients who had prolonged symptoms consistent with CSF shunt failure and stable normal ventricular size were demonstrated at the time of surgery to have obstruction of their CSF shunts. CONCLUSION: Ventricular enlargement is a common but not sine qua non indicator of CSF shunt failure, even after weeks or months of elevated intracranial pressure, and therefore cannot be relied upon for the diagnosis of CSF shunt failure. Although an increase in ventricular size is usually seen relatively early in the course of shunt malfunction, stable normal ventricular size in patients with symptoms and signs that are consistent with shunt failure can delay the diagnosis with potentially serious adverse consequences.

Adolescent↗

PubMed2006

Nonaccidental head trauma as a cause of childhood death.

OBJECT: The authors present the demographic and clinical information in 36 children who died as a result of abusive head trauma at a Level 1 pediatric trauma center between January 1, 1997, and January 1, 2004. METHODS: Abusive head trauma was defined as radiographic evidence of intracranial injury and documentation from a multidisciplinary child protection team that the injury was nonaccidental. There was no sex bias for the children in the 1st year of life (nine girls, nine boys). In children older than 1 year of age, boys were much more likely to be victims (14 boys, four girls). At the time of admission, every child exhibited a seriously impaired level of consciousness and 81% had retinal hemorrhages. Injuries to other organ systems were rare (17%). The most common abnormality found on neuroimaging studies was subdural hematoma. Six children underwent craniotomy for extraaxial hematomas. Death occurred within 24 hours after hospital admission in one half of the cases. CONCLUSIONS: Abusive head trauma was the cause of death in 36 (86%) of the 42 children whose deaths were classified as nonaccidental at the Children's Hospital in Denver between 1997 and 2003. The authors were unable to identify anything that could have been done from a medical or neurosurgical viewpoint to prevent the deaths of these children after they came to medical attention.

Adolescent↗

PubMed2003

Human alloreactive CTL interactions with gliomas and with those having upregulated HLA expression from exogenous IFN-gamma or IFN-gamma gene modification.

By flow cytometry, a panel of 18 primary glioma cell explants exhibited high expression of class I HLA-A, B, C, but class II HLA-DR expression was absent. Freshly isolated normal brain cells displayed little or no HLA antigens. Alloreactive cytotoxic T lymphocytes (aCTL), sensitized to the HLA of the patient, were generated in a one-way mixed lymphocyte response (MLR). The specificity of aCTL was confirmed to be to target cells (patient glioma cells or lymphoblasts) expressing the relevant HLA antigens. However, nontumor patient-specific aCTL did not lyse normal brain cells. Titration of antibodies to HLA class I into cytotoxicity assays blocked lysis of gliomas by aCTL, confirming aCTL T cell receptor (TCR) interactions with the class I antigen on gliomas. Furthermore, aCTL interactions with glioma cells caused their apoptosis. Coincubations of aCTL with gliomas resulted in upregulated cytokine secretion. Importantly, dexamethasone, an immunosuppressive steroid used for brain edema, did not affect aCTL lytic function against tumor, indicating that steroid-dependent patients may benefit from the immunotherapy. We also explored the use of interferon-gamma (IFN-gamma) to increase aCTL tumor recognition. Coincubation of gliomas with exogenous IFN-gamma (500 U/ml, 48 h) caused a 3-fold upregulation of HLA class I and a slight induction of class II antigen expression. Gene-modified glioma cells producing IFN-gamma similarly displayed upregulated HLA expression. Glioma cells incubated with exogenous IFN-gamma or IFN-gamma-transduced glioma cells were more susceptible to lysis by aCTL than their parental counterparts, thus supporting the concept of combining IFN-gamma cytokine gene therapy with adoptive aCTL immunotherapy for brain tumor treatment.

Anti-Inflammatory Agents↗

PubMed2003

Cystoventricular shunting of intracranial arachnoid cysts.

Ten patients with intracranial arachnoid cysts were treated with direct shunting of the cyst to a lateral ventricle. The strategic goal of cystoventricular shunting is to establish physiologically normal intracranial pressure relationships, rather than cyst obliteration. Cystoventricular shunts were successful in treating single and multiple intracranial cysts in supratentorial and infratentorial locations and in patients with normal and enlarged lateral ventricles. Cystoventricular shunting is conceptually simple as well as effective and reliable.

Adolescent↗

PubMed2003

Cranial bone fixation: review of the literature and description of a new procedure.

OBJECT: Fixation of cranial bone flaps should be reliable, safe, rapid, esthetically acceptable, and inexpensive. It should require minimal foreign material, and ideally it should produce no artifacts on neuroimaging. The authors describe a new procedure that meets these criteria. METHODS: In this procedure, the cranial bone flap is affixed by tightly packing into the surrounding kerf the shims of bone that are harvested from the under edge of the free bone flap and then securing the flap with absorbable sutures. The result is a keystone arrangement that locks the flap into the craniotomy site. CONCLUSIONS: The bone shim method for cranial bone fixation was used successfully in 386 of 387 consecutive craniotomies in adults. This procedure for cranial flap fixation is reliable, safe, and rapid, and it achieves solid structural stability with excellent esthetic results. No special tools are required, and, because no plates, screws, or wire are used, all problems associated with these materials are avoided, including the artifacts on postoperative neuroimaging. This method is conceptually simple and quite inexpensive.

Adolescent↗

PubMed2002

Cerebellar mutism associated with a midbrain cavernous malformation. Case report and review of the literature.

The authors report a case of cerebellar mutism arising from a hemorrhagic midbrain cavernous malformation in a 14-year-old boy. No cerebellar lesion was identified; however, edema of the dorsal midbrain was noted on postoperative magnetic resonance images. Dysarthric speech spontaneously returned and then completely resolved to normal speech. This case provides further evidence for the theory that involvement of the dentatothalamic tracts, and not a cerebellar lesion per se, is the underlying cause of "cerebellar" mutism.

Adolescent↗