Biomedical subjects

P Francel

Publications and source records attributed to P Francel.

7 recordsLinked to original sources

PubMed2004

Deep brain stimulation for Parkinson's disease: association between stimulation parameters and cognitive performance.

Chronic subthalamic nucleus stimulation produces inconsistent patterns of cognitive change in Parkinson's disease patients. Individually tailored stimulation parameters may contribute to this variable pattern of change. Systematic variation of amplitude, pulse width, and rate of stimulation has been reported to produce unique changes in motor and limbic response. To evaluate the association between stimulation parameters and cognitive/behavioral response, neuropsychological performance and stimulation parameter data of 8 Parkinson's disease patients were submitted to Pearson r correlation analysis. Results indicate that each stimulation parameter was significantly associated with a subset of measures. The current findings raise the possibility that adverse cognitive/behavioral responses may be treated through parameter modification while maintaining motor symptom efficacy.

Aged↗

PubMed2001

The timing of physiologic closure of the metopic suture: a review of 159 patients using reconstructed 3D CT scans of the craniofacial region.

PURPOSE: The purpose of this study was to determine the normal physiologic timing of the closure of the metopic suture in non-craniosynostotic patients. METHODS: This clinical study involved a consecutive series of infants and young children who underwent 3D CT-scan evaluation for deformational plagiocephaly or suspected traumatic head injury. All patients with evidence of craniosynostosis were excluded from the study. Every infant and child referred to our Craniofacial Team for deformational plagiocephaly between 1997 and 2000 (n = 84) received a baseline pre-treatment 3D CT-scan of the head. Our study also included a series of selected pediatric trauma patients (1 to 24 months of age) between 1997 and 2000 (n = 75) who received CT-scan to rule out head injury. The CT scan results were reviewed for closure of metopic suture by a single observer. RESULTS: The earliest evidence of metopic suture closure was at 3 months, the age at which 33% of patients (4/12) were closed. At 5 months of age, 59% (13/22) of sutures were closed. At 7 months of age, 65% (15/23) were closed. At 9 months of age, 100% (10/10) were closed. All patients greater than 9 months of age within the study had complete metopic suture closure. CONCLUSION: Our findings suggest that normal or physiologic closure of the metopic suture occurs much earlier than what has been previously described. This study establishes that metopic fusion may normally occur as early as 3 months of age, and that complete fusion occurred by 9 months of age in all patients in our series. Therefore, 3-D CT scans showing complete closure of the metopic suture at an early age (3 to 9 months) cannot be considered as evidence of metopic synostosis, and thus, should not be the decisive factor for early surgical intervention.

Age Factors↗

PubMed2001

Neurodevelopment in children with single-suture craniosynostosis and plagiocephaly without synostosis.

The objective of this study was to determine whether children with nonsyndromic craniosynostosis and plagiocephaly without synostosis demonstrated cognitive and psychomotor delays when compared with a standardized population sample. This was the initial assessment of a larger prospective study, which involved 21 subjects with nonsyndromic craniosynostosis (mean age, 10.9 months) and 42 subjects with plagiocephaly without synostosis (mean age, 8.4 months). Each child was assessed using the Bayley Scales of Infant Development-II (BSID-II) for cognitive and psychomotor development before therapeutic intervention (surgery for craniosynostosis and molding-helmet therapy for plagiocephaly without synostosis). The distribution of the scores was divided into four groups: accelerated, normal, mild delay, and significant delay. The distributions of the mental developmental index (MDI) and the psychomotor developmental index (PDI) were then compared with a standardized Bayley's age-matched population, using Fisher's exact chi-square test. Within the craniosynostosis group, the PDI scores were significantly different from the standardized distribution (p < 0.001). With regard to the PDI scores, 0 percent of the subjects in the craniosynostosis group were accelerated, 43 percent were normal, 48 percent had mild delay, and 9 percent had significant delay. In contrast, the MDI scores were not statistically different (p = 0.08). Within the group with plagiocephaly without synostosis, both the PDI and MDI scores were significantly different from the normal curve distribution (p < 0.001). With regard to the PDI scores, 0 percent of the subjects in the group with plagiocephaly without synostosis were accelerated, 67 percent were normal, 20 percent had mild delay, and 13 percent had significant delay. With regard to the MDI scores, 0 percent of the subjects in this group were accelerated, 83 percent were normal, 8 percent had mild delay and 9 percent had significant delay. This study indicates that before any intervention, subjects with single-suture syndromic craniosynostosis and plagiocephaly without synostosis demonstrate delays in cognitive and psychomotor development. Continued postintervention assessments are needed to determine whether these developmental delays can be ameliorated with treatment.

Child Development↗

PubMed2001

Reossification of the orbital wall following ventral translocation of the fronto-orbital bar and cranial vault remodeling.

The purposes of this study were to determine the extent of ossification of the orbit following ventral translocation of the fronto-orbital bar and to find out whether age at the time of the procedure and presence of a concomitant syndrome adversely affect ossification. A retrospective review of 27 patients with craniosynostosis was conducted at the St. Louis Children's Hospital and the Children's Hospital of Oklahoma. Patients with preoperative, perioperative, and postoperative three-dimensional computed tomography scans were included. Eighty-eight percent of the lateral orbital wall defects and 92 percent of the defects within the roof of the orbit ossified completely in the postoperative period. When syndromic patients were compared with nonsyndromic patients (based on clinical findings only), three of the 19 syndromic defects and three of the 30 nonsyndromic defects demonstrated incomplete ossification in the lateral orbital wall (p > 0.05). Similarly, two of the 19 syndromic defects and two of the 30 nonsyndromic defects demonstrated incomplete ossification within the roof of the orbit (p > 0.05). With respect to age at the time of the procedure, four of the 37 defects and two of the 12 defects demonstrated incomplete ossification in the lateral orbital wall for age at the time of the procedure less than 12 months and greater than 12 months, respectively (p > 0.05). Similarly, two of the 37 defects and two of the 12 defects had incomplete ossification within the roof of the orbit for age at the time of the procedure less than 12 months versus more than 12 months, respectively (p > 0.05). Ossification of the orbital wall and roof is complete in the majority of cases within 1 year after the procedure, and neither age at the time of the procedure nor presence of a concomitant syndrome adversely affects ossification of the orbit after ventral translocation of the fronto-orbital bandeau.

Bone Transplantation↗

PubMed2001

Functional reorganization of motor cortex due to brain tumor: a case report.

We report the case of a 39-year-old man with a brain tumor and 12 years of intractable partial epilepsy with secondary generalization. After extensive noninvasive and invasive evaluation the seizure focus was localized to the right fronto-parietal region. Functional cortical mapping (FCM) was performed after craniotomy and implantation of a subdural grid with 40 electrodes covering the epileptogenic focus and the adjacent cortex. A Grass Model S12 Stimulator was used to deliver gradual increments of current and stimulus duration with fixed frequency of 10 Hz and pulse duration of 500 microsec for defining eloquent cortex next to the seizure focus. FCM demonstrated cortical representation of eye anterior to and hand posterior and inferior to expected locations on the motor cortex compared to the classical homunculus. Subsequently, he underwent resection of an oligodendroglioma. This case demonstrates that the brain undergoes reorganization of cortical motor representation as a result of pathological lesions in the brain.

Adult↗

PubMed1996

Acrylic cranioplasty using miniplate struts.

OBJECTIVE: Cranioplasty using acrylic is a common procedure in patients with cranial defects secondary to trauma, infection, or tumor. The limitations of this technique include poor adherence of the acrylic to surrounding bone and difficulty in achieving a proper cosmetic contour in complicated cranial defects, especially those involving the orbital rim. The authors have been continually developing techniques of cranioplasty. METHODS: Ten consecutive cranioplasties were performed over the past 5 years using this new technique. TECHNIQUE: The authors describe a technique using miniplates as struts to which the acrylic is applied using a "reinforced concrete" principle. RESULTS/CONCLUSION: All patients achieved excellent cosmetic results with no complications. This technique allows contour of the repair site while the acrylic is curing and provides a more resilient resulting prosthesis.

Bone Cements↗

PubMed1988

Bradykinin induces the bi-phasic production of lysophosphatidyl inositol and diacylglycerol in a dorsal root ganglion X neurotumor hybrid cell line, F-11.

Bradykinin acts on the dorsal root ganglion X neuroblastoma hybrid cell line F-11 to stimulate the rapid elevation of inositol trisphosphate (IP3) and intracellular calcium. We now show an equally rapid release of arachidonyl labeled diacylglycerol (DAG), (243 +/- 32% of control). This first peak of diacylglycerol production was inhibitable by either pretreatment with 200 ng/ml of pertussis toxin overnight or by 10 nM tetradecanoylphorbol acetate (TPA). In addition, a second, more sustained release occurred, plateauing at approximately five minutes (304 +/- 16%). The second peak of DAG was unaffected by these TPA or pertussis pre-incubations. Simultaneous analysis of inositol-labeled phospholipids showed that the initial IP3 and DAG peaks corresponded to initial decreases in phosphoinositides PIP2 and PIP whereas PI increased slightly over this same time period. In contrast, at 5-30 minutes, PIP2 and PIP returned to normal levels, but PI gradually decreased to 75% of control values. Likewise, TPA blocked this early PIP and PIP2 breakdown, but had no effect on the delayed breakdown of monophosphatidylinositol (PI). Bradykinin also induced an equally rapid increase in lysophosphatidyl inositol (lyso-PI) with a peak around 10-30 seconds, and a second more sustained peak after 10 minutes. This production of lyso-PI was not affected by prior treatment with TPA or pertussis toxin. The initial and the sustained phases of diacylglycerol production probably result from different biochemical mechanisms and/or substrates.

Animals↗