The role of neuroimaging in the evaluation process of children with isolated sixth nerve palsy

Purpose

The purpose of this study was to assess the role of neuroimaging in identifying the etiology of pediatric isolated sixth nerve palsy (SNP).

Methods

A retrospective cohort study was conducted of all patients younger than 18 years of age with an isolated SNP seen at our medical center between 2003 and 2011.

Results

Sixteen children (nine girls; mean age, 4.5 years) with isolated SNP were identified during an 8-year period. Only cases with normal optic disk appearance and otherwise normal neurological examination were included into this study. Thus, 12 other children with SNP were excluded: ten children with papilledema, one child who developed a SNP following a resection of a brain tumor, and one with hydrocephalus and a shunt malfunction. All cases of isolated SNP were unilateral (ten left eyes). The most common cause for the SNP in these children was a tumor that was found in five patients. Other etiologies encountered in decreasing frequencies were: benign recurrent SNP (in four children), postviral or vaccination (in three children), and one case each of post trauma, Chiari malformation, congenital, and undetermined. Children who were found to have a tumor (9.9?±?5.5 years) were significantly older (P?=?0.019) than children who did not have a tumor (2.1?±?1.8 years).

Conclusions

Isolated SNP can be the presentation of a brain tumor in children, and therefore, early neuroimaging of the brain is recommended, especially in older children.     

Children's attentional skills 5 years post-TBI

OBJECTIVE: While a small number of research papers have reported findings on attentional deficits following pediatric traumatic brain injury (TBI), no study to date has reported findings in this area at 5 years post-TBI in very young children. This study examined attentional skills in a group of children who had sustained a mild, moderate, or severe TBI between the ages of 2 and 7 years. METHODS: The sample comprised 70 children, 54 of these had sustained a TBI and 16 the non-injured control group. Children were assessed 5 years post-TBI, with focus on tests of attentional ability. RESULTS: Attentional and processing speed (PS) deficits do occur and persist up to 5 years post-TBI, particularly following severe TBI in early childhood. Predictors of attentional outcomes varied depending on the component of attention investigated. CONCLUSIONS: Those skills developing or emerging at time of injury (e.g., sustained attention, shifting attention, divided attention, PS) are more compromised and may not develop at a normal rate of post-injury.     

Surgical delivery of drug releasing poly(lactic-co-glycolic acid)/poly(ethylene glycol) paste with in vivo effects against glioblastoma

Introduction

The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.

Methods

Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.

Results

Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.

Conclusions

Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models.     

Introduction of rat growth hormone gene into mouse fibroblasts via a retroviral DNA vector: expression and regulation.

We have introduced the rat growth hormone gene into mouse fibroblasts via a retroviral DNA vector. The ability of the viral DNA to induce foci in the recipient cells was used as a dominant selection marker. Several copies of rat growth hormone DNA were integrated in the mouse cells. The transformed mouse cells expressed rat growth hormone-specific mRNA and secreted mature rat growth hormone. In rat cells, the expression of this gene is regulated by glucocorticoids. We demonstrate that hormone-dependent regulation transfers with the clone and thus appears to be an intrinsic property of the gene or its RNA products.     

Elevated tricuspid regurgitant jet velocity in subgroups of thalassemia patients: insight into pathophysiology and the effect of splenectomy

A high tricuspid regurgitant jet velocity (TRV) signifies a risk for or established pulmonary hypertension (PH), which is a serious complication in thalassemia patients. The underlying pathophysiology in thalassemia subgroups and potential biomarkers for early detection and monitoring are not well defined, in particular as they relate to spleen removal. To better understand some of these unresolved aspects, we examined 76 thalassemia patients (35 non-transfused), 25 splenectomized non-thalassemia patients (15 with hereditary spherocytosis), and 12 healthy controls. An elevated TRV (>2.5 m/s) was found in 25/76 (33 %) of the patients, confined to non-transfused or those with a late start of transfusions, including patients with hemoglobin H-constant spring, a finding not previously described. These non or late-transfused patients (76 % splenectomized) had significantly increased platelet activation (sCD40L), high platelet count, endothelial activation (endothelin-1), and hemolysis (LDH, plasma-free Hb), while hypercoagulable and inflammatory markers were not significantly increased. The same markers were increased in the seven patients with confirmed PH on cardiac catheterization, suggesting their possible role for screening patients at risk for PH. A combination of hemolysis and absence of spleen is necessary for developing a high TRV, as neither chronic hemolysis in the non-splenectomized thalassemia patients nor splenectomy without hemolysis, in the non-thalassemia patients, resulted in an increase in TRV.