Thursday, January 2, 2014

The baric probe: a novel long-term implantable intracranial pressure monitor with ultrasound-based interrogation

Limbrick DD Jr, Lake S, Talcott M, Alexander B, Wight S, Willie JT, Richard WD, Genin GM, Leuthardt EC. (2012)  The baric probe: a novel long-term implantable intracranial pressure monitor with ultrasound-based interrogation.  Journal of Neurosurgery: Pediatrics. 2012 Dec;10(6):518-24.

OBJECT:

Prompt diagnosis of shunt malfunction is critical in preventing neurological morbidity and death in individuals with hydrocephalus; however, diagnostic methods for this condition remain limited. For several decades, investigators have sought a long-term, implantable intracranial pressure (ICP) monitor to assist in the diagnosis of shunt malfunction, but efforts have been impeded by device complexity, marked measurement drift, and limited instrumentation lifespan. In the current report, the authors introduce an entirely novel, simple, compressible gas design that addresses each of these problems.

METHODS:

The device described herein, termed the "baric probe," consists of a subdural fluid bladder and multichannel indicator that monitors the position of an air-fluid interface (AFI). A handheld ultrasound probe is used to interrogate the baric probe in vivo, permitting noninvasive ICP determination. To assess the function of device prototypes, ex vivo experiments were conducted using a water column, and short- and long-term in vivo experiments were performed using a porcine model with concurrent measurements of ICP via a fiberoptic monitor.

RESULTS:

Following a toe region of approximately 2 cm H(2)O, the baric probe's AFI demonstrated a predictable linear relationship to ICP in both ex vivo and in vivo models. After a 2-week implantation of the device, this linear relationship remained robust and reproducible. Further, changes in ICP were observed with the baric probe, on average, 3 seconds in advance of the fiberoptic ICP monitor reading.

CONCLUSIONS:

The authors demonstrate "proof-of-concept" and feasibility for the baric probe, a long-term implantable ICP monitor designed to facilitate the prompt and accurate diagnosis of shunt malfunction. The baric probe showed a consistent linear relationship between ICP and the device's AFI in ex vivo and short- and long-term in vivo models. With a low per-unit cost, a reduced need for radiography or CT, and an indicator that can be read with a handheld ultrasound probe that interfaces with any smart phone, the baric probe promises to simplify the care of patients with shunt-treated hydrocephalus throughout both the developed and the developing world.
doi: 10.3171/2012.8.PEDS11565

Friday, December 27, 2013

Influenza and congenital anomalies: a systematic review and meta-analysis.

Luteijn JM, Brown MJ, Dolk H. (2013) Influenza and congenital anomalies: a systematic review and meta-analysis. Human Reproduction. 2013 Dec 22. [Epub ahead of print]

Abstract

STUDY QUESTION:

Does first trimester maternal influenza infection increase the risk of non-chromosomal congenital anomalies (CA)?

SUMMARY ANSWER:

First trimester maternal influenza exposure is associated with raised risk of a number of non-chromosomal CA, including neural tube defects, hydrocephaly, congenital heart defects, cleft lip, digestive system defects and limb reduction defects.

WHAT IS KNOWN ALREADY:

Hyperthermia is a well-established risk factor for neural tube defects. Previous studies suggest influenza may be a risk factor not only for neural tube defects, but also other CA. No systematic review has previously been undertaken.

STUDY DESIGN, SIZE, DURATION:

Systematic review and meta-analysis. A search of EMBASE and PUBMED was performed for English and Dutch studies published up to July 2013. A total of 33 studies (15 case-control, 10 cohort and 8 ecological) were included in the systematic review of which 22 studies were included in the meta-analysis.

PARTICIPANTS/MATERIALS, SETTINGS, METHODS:

A total of 29 542 babies with congenital anomaly (1112 exposed) from case-control studies and 1608 exposed pregnancies resulting in 56 babies with congenital anomaly from cohort studies were included in the meta-analysis. Maternal influenza exposure was defined as any reported influenza, influenza-like illness or fever with flu, with or without serological or clinical confirmation during the first trimester of pregnancy. Data for 24 (sub)groups with congenital anomaly available from ≥3 studies were analysed using the DerSimonian-Laird random effects model. The hypothesis of publication bias was assessed using funnel plots and risk of bias of included studies was assessed using a slightly modified version of the Newcastle-Ottawa scale.

MAIN RESULTS AND THE ROLE OF CHANCE:

First trimester maternal influenza exposure was associated with an increased risk of any congenital anomaly [adjusted odds ratio (AOR) 2.00, 95% CI: 1.62-2.48], neural tube defects [odds ratio (OR) 3.33, 2.05-5.40], hydrocephaly (5.74, 1.10-30.00), congenital heart defects (1.56, 1.13-2.14), aortic valve atresia/stenosis (AOR 2.59, 1.21-5.54), ventricular septal defect (AOR 1.59, 1.24-2.14), cleft lip (3.12, 2.20-4.42), digestive system (1.72, 1.09-2.68) and limb reduction defects (2.03, 1.27-3.27). An increased risk for cleft lip (but not for cleft palate) was also reported by ecological studies not included in the meta-analysis. Study outcomes reported for 27 subgroups of congenital anomaly could not be included in the meta-analysis. Visual inspection of funnel plots did not suggest evidence for publication bias.

LIMITATIONS, REASONS FOR CAUTION:

This study enrolled observational studies that can be subject to limitations such as confounding, retrospective maternal exposure reports and non-response of intended participants. Influenza exposed pregnancies can also have been exposed to influenza related medication.

WIDER IMPLICATIONS OF THE FINDINGS:

Prevention of influenza in pregnant women may reduce congenital anomaly risk, and would be relevant to more than just neural tube defects. More research is needed to determine whether influenza and/or its related medication is teratogenic, to determine the role of hyperthermia in teratogenicity and the role of other environmental factors such as nutritional status in determining susceptibility.

STUDY FUNDING/ COMPETING INTERESTS:

Funded by the EC, under the framework of the EU Health Programme 2008-2013, Grant Agreement 2010 22 04 (Executive Agency for Health & Consumers). No competing interests.

KEYWORDS:

congenital anomalies, influenza, meta-analysis, observational studies, public health

PMID: 24365800

Thursday, December 26, 2013

Longitudinal mediators of achievement in mathematics and reading in typical and atypical development.

Barnes MA, Raghubar KP, English L, Williams JM, Taylor H, Landry S. (2013) Longitudinal mediators of achievement in mathematics and reading in typical and atypical development. Journal of Expimental Child Psychology. 2014 Mar;119:1-16. 

Longitudinal studies of neurodevelopmental disorders that are diagnosed at or before birth and are associated with specific learning difficulties at school-age provide one method for investigating developmental precursors of later-emerging academic disabilities. Spina bifida myelomeningocele (SBM) is a neurodevelopmental disorder associated with particular problems in mathematics, in contrast to well-developed word reading. Children with SBM (n=30) and typically developing children (n=35) were used to determine whether cognitive abilities measured at 36 and 60months of age mediated the effect of group on mathematical and reading achievement outcomes at 8.5 and 9.5years of age. A series of multiple mediator models showed that: visual-spatial working memory at 36months and phonological awareness at 60months partially mediated the effect of group on math calculations, phonological awareness partially mediated the effect of group on small addition and subtraction problems on a test of math fluency, and visual-spatial working memory mediated the effect of group on a test of math problem solving. Groups did not differ on word reading, and phonological awareness was the only mediator for reading fluency and reading comprehension. The findings are discussed with reference to theories of mathematical development and disability and with respect to both common and differing cognitive correlates of math and reading.

doi: 10.1016/j.jecp.2013.09.006.


The prevalence of small intestinal bacterial overgrowth and methane production in patients with myelomeningocele and constipation.

Ojetti V, Bruno G, Paolucci V, Triarico S, D'aversa F, Ausili E, Gasbarrini A, Rendeli C. (2013) The prevalence of small intestinal bacterial overgrowth and methane production in patients with myelomeningocele and constipation. Spinal Cord. 2013 Nov 19.

Study design:Prospective study.Objectives:The objective of this study was to assess the prevalence of small intestinal bacterial overgrowth (SIBO), methane (CH4) production and orocecal transit time (OCTT) in children affected by myelomeningocele.Setting:This study was conducted at the Catholic University in Rome, Italy.Methods:Eighteen (6M/12F; 16.4±7.6 years) children affected by myelomeningocele were enrolled. All subjects underwent H2/CH4 lactulose breath tests to assess SIBO and OCTT. All patients performed a visual analog scale to investigate abdominal pain, bloating and flatulence, and maintained a diary of the frequency and consistency of the stool during the previous 7 days. A nephro-urological clinical evaluation of the number of urinary tract infections (UTIs) and neurogenic bowel disease score were also performed.Results:Thirty-nine percent (7/18) of the children showed SIBO and 61% (11/18) presented a delayed OCTT. Moreover 44.4% (8/18) produced high levels of CH4. Interestingly, all myelomeningocele children who produced CH4 showed a delayed OCTT and a higher incidence of UTI, with a lower frequency of evacuation, compared with those with a normal or accelerated OCTT.Conclusion:The association between CH4 and constipation suggests that CH4 has an active role in the development of constipation. One of the most interesting features of our study is to identify a correlation between myelomeningocele, CH4, delayed OCTT and UTI. The intestinal decontamination with locally acting drugs in these children may reduce the number of UTIs and improve intestinal motility.

doi: 10.1038/sc.2013.131.

Spina bifida grown up.


Liptak GS, Garver K, Dosa NP. (2013) Spina bifida grown upJournal of Developmental and Behavioral Pediatrics. 2013 Apr;34(3):206-15.



The majority of people with spina bifida in the United States are now older than 18 years of age. Health care delivery for adults with this condition should include routine surveillance for common conditions such as hypertension, hyperlipidemia and cancer. It should also address spina bifida-related complications such as pressure sores, lymphedema, sexual dysfunction and infertility, and hydrocephalus, as well as chiari-related symptoms such as sleep apnea and urologic and renal functioning. Almost all adults with spina bifida benefit from regular followup with specialists in urology, neurosurgery and physiatry. Health care providers for adults with spina bifida should recognize the impact of executive dysfunction and nonverbal learning disability on self management, independent living, and employment in adults with spina bifida.

doi: 10.1097/DBP.0b013e31828c5f88.

Young Adults with Spina Bifida May Have Higher Occurrence of Prehypertension and Hypertension.

Stepanczuk BC, Dicianno BE, Webb TS. (2013) Young Adults with Spina Bifida May Have Higher Occurrence of Prehypertension and Hypertension.  American Journal of Physical Medicine & Rehabilitation. 2013 Oct 1. 

Abstract

OBJECTIVE:

The aims of this study were to determine the occurrence of prehypertension and high blood pressure in adults with spina bifida (SB) and to examine relationships among blood pressure, cardiovascular disease risk factors, and SB-specific factors.

DESIGN:

This is a cross-sectional, retrospective analysis of adults with SB. SB-specific factors and cardiovascular disease risk factors were compared among subjects with high blood pressure, subjects with blood pressure in the prehypertensive range, and normotensive subjects using the χ, Kruskal-Wallis, or Fisher's exact tests.

RESULTS:

Of 225 subjects, the occurrence of prehypertension and high blood pressure was 27% (n = 22) and 27% (n = 22) for ages 18-29 yrs, 35% (n = 26) and 41% (n = 30) for ages 30-39 yrs, 18% (n = 8) and 66% (n = 29) for ages 40-49 yrs, and 21% (n = 5) and 67% (n = 16) for 50 yrs or older, respectively. Of the subjects with high blood pressure, 56% were men, 14% had obstructive sleep apnea, 14% had diabetes, 19% had renal dysfunction, 38% used tobacco, 16% had hydronephrosis, and 71% had a shunt. The groups differed significantly with respect to diabetes (P = 0.004), bladder procedures (P = 0.001), and renal dysfunction (P < 0.001), with higher proportions of subjects with high blood pressure having these comorbidities.

CONCLUSIONS:

Fewer than half of the subjects were considered normotensive. A greater proportion of young adults with SB appear to have high blood pressure compared with the general United States population. Because elevated blood pressure is an independent, modifiable risk factor of cardiovascular disease, these findings support early screening and intervention for elevated blood pressure in individuals with SB.

Monday, December 23, 2013

Goal Management Training improves everyday executive functioning for persons with spina bifida: Self-and informant reports six months post-training.

Stubberud J, Langenbahn D, Levine B, Stanghelle J, Schanke AK. (2013) Goal Management Training improves everyday executive functioning for persons with spina bifida: Self-and informant reports six months post-training. Neuropsycholical Rehabilitation. 2013 Oct 30

Executive dysfunction accounts for significant disability for many patients with spina bifida (SB), thus indicating the need for effective interventions aimed at improving executive functioning in this population. Goal Management Training™ (GMT) is a cognitive rehabilitation approach that targets disorganised behaviour resulting from executive dysfunction, and has received empirical support in studies of other patient groups. The purpose of this study was to determine if GMT would lead to perceived improved executive functioning in the daily lives of patients with SB, as evidenced by reduced report of dysexecutive problems in daily life on self- and informant questionnaires. Thirty-eight adults with SB were included in this randomised controlled trial (RCT). Inclusion was based upon the presence of executive functioning complaints. Experimental subjects (n = 24) received 21 hours of GMT, with efficacy of GMT being compared to results of subjects in a wait-list condition (n = 14). All subjects were assessed at baseline, post-intervention, and at six-month follow-up. Self-report measures indicated that the GMT group's everyday executive functioning improved significantly after training, lasting at least 6 months post-treatment.

There were no significant effects on informant-report questionnaires. Overall, these findings indicate that executive difficulties in everyday life can be ameliorated for individuals with congenital brain dysfunction.

doi: 10.1080/09602011.2013.847847