Llewellyn Padayachy

MBChB, FCS, MMed, PhD
16.73

Publications

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    Llewellyn Padayachy · Reidar Brekken · Graham Fieggen · Tormod Selbekk
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    ABSTRACT: Background: Raised intracranial pressure (ICP) may lead to increased stiffness of the optic nerve sheath (ONS). Objective: To develop a method for analyzing ONS dynamics from transorbital ultrasound and investigate a potential difference between patients with raised ICP vs normal ICP. Methods: We retrospectively analyzed data from 16 patients (≤12 years old) for whom ultrasound image sequences of the ONS had been acquired from both eyes just before invasive measurement of ICP. Eight patients had an ICP ≥20 mm Hg. The transverse motion on each side of the ONS was estimated from ultrasound, and Fourier analysis was used to extract the magnitude of the displacement corresponding to the heart rate. By calculating the normalized absolute difference between the displacements on each side of the ONS, a measure of ONS deformation was obtained. This parameter was referred to as the deformability index. According to our hypothesis, because deformability is inversely related to stiffness, we expected this parameter to be lower for ICP ≥20 mm Hg compared with ICP <20 mm Hg. The one-sided Mann-Whitney U test was used for statistical comparison. Results: The deformability index was significantly lower in the group with ICP ≥20 mm Hg (median value 0.11 vs 0.24; P = .002). Conclusion: We present a method for assessment of ONS pulsatile dynamics using transorbital ultrasound imaging. A significant difference was noted between the patient groups, indicating that deformability of the ONS may be relevant as a noninvasive marker of raised ICP. The clinical implications are promising and should be investigated in future clinical studies. Abbreviations: AUC, area under curveICP, intracranial pressureONS, optic nerve sheathONSD, optic nerve sheath diameterROC, receiver operating characteristicThis is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND), which permits downloading and sharing the work provided it is properly cited. The work cannot be changed in any way or used commercially.
    Full-text · Article · Jan 2016 · Neurosurgery

  • No preview · Article · Dec 2015
  • Llewellyn C Padayachy · A Graham Fieggen

    No preview · Article · Jun 2015 · Child s Nervous System
  • Llewellyn C Padayachy · Tracy Kilborn · Henri Carrara · Anthony A Figaji · Graham A Fieggen
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    ABSTRACT: The purpose of this study was to investigate the value of the change in optic nerve sheath diameter (ONSD) as a radiological marker of endoscopic third ventriculostomy (ETV) outcome in children. Magnetic resonance imaging (MRI) scans of patients on whom ETVs were performed between the periods of January 2009 and June 2013 were reviewed. ONSD measurements on pre- and post-operative images were performed by two blinded observers, and the relationship between the change in these measurements and outcome from ETV were investigated. These findings were then also compared to conventional imaging features associated with ETV outcome. MRI scans of 24 patients were adequate to measure the ONSD pre- and post-operatively. In patients with successful ETV (n = 19), the mean change in ONSD was 0.73 mm and in patients with a failed ETV (n = 5), the mean change in ONSD was 0.18 mm (p = 0.0007). A change in ONSD of 7.5 % of the initial measurement demonstrated a sensitivity of 92.9 % and a sensitivity of 85.7 % for ETV outcome (area under the receiver operating characteristic curve (AUROC) = 0.96). Change in ONSD is a useful radiological marker of ETV outcome and may be used in combination with conventional radiological parameters to aid decision-making in this difficult group of patients.
    No preview · Article · Mar 2015 · Child s Nervous System
  • Llewellyn Padayachy
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    ABSTRACT: Transorbital ultrasound measurement of optic nerve sheath parameters as a non-invasive marker of intracranial pressure in children Padayachy LC, Carrara H, Figaji AA, Selbekk T, Brekken R, Fieggen AG Introduction: Raised intracranial pressure (ICP) remains the most commonly encountered problem in paediatric neurosurgery. While invasive ICP monitoring remains the current gold standard, it has certain disadvantages. The benefit of a reliable, reproducible, non-invasive technique for assessing ICP is distinct. We present our findings using transorbital assessment of the optic nerve sheath diameter (ONSD) as a non-invasive marker of intracranial pressure. Methods: We conducted a prospective, blinded observational study in children under the age of 14 years. The ONSD image acquisition was performed in both eyes, in two planes, i.e. sagittal and axial. Measurements were performed using a 17 MHZ linear array probe, after induction of anesthesia and prior to invasive measurement of ICP. The average ONSD measurements of both eyes were then correlated with the ICP measurements from invasive readings, as well as with other physiological parameters. We also performed a subgroup analysis using a novel technique for measuring the compliance related dynamics of the nerve sheath in an effort to improve the specificity of the readings. Results: We performed 1212 ONSD measurements in 103 patients. The mean ONSD for ICP < 20 mmHg was 5.23 ± 0.09 mm, and for ICP >20mmHg was 6.08 ± 0.75 mm (p < 0.0001). An ONSD measurement of 5mm has a 85.7% sensitivity, 59% specificity (ROC = 0.78) for ICP >20mmHg in children < 12 months old and in children over ≥ 12months old, an ONSD measurement of 5.3mm has a 90.63% sensitivity, 58.6% specificity (ROC = 0.77) for ICP >20mmHg. Although the number of dynamic measurements performed are limited (n=16) there is a linear relationship with ONSD (r = 0.51, p=0.09) Conclusion: Transorbital ONSD measurement is a sensitive and reproducible, non-invasive method for assessing intracranial pressure in children. Dynamic measurements of the optic nerve sheath may serve to further improve the value of this non-invasive technique.
    No preview · Conference Paper · Nov 2014
  • Llewellyn Padayachy
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    ABSTRACT: Surgical management of moyamoya disease in children Llewellyn Padayachy, Anthony Figaji, Graham Fieggen Introduction: Moyamoya disease is a rare, progressive steno-occlusive condition affecting the internal carotid artery and its distal branches. It may affect both adults and children, and is thought to account for around 6% of arterial ischemic stroke in children. Methods: This study represents prospectively collected data between January 2010 and December 2013 on children with moyamoya vasculopathy at a tertiary paediatric treatment centre. All patients were managed following an institutional protocol for moyamoya vasculopathy. The clinical presentation, natural history, number of ischemic episodes, associated pathology, angiographic distribution, Kawasaki grading, SPECT changes, surgical technique and outcome were analysed. Results: We have treated 14 children with moyamoya vasculopathy over this period, performing 10 indirect revascularisation procedures in 9 children. The mean number of pre-operative ischemic episodes was 3.8 ± 2.1, the median initial Kawasaki grading was 3. The mean follow-up period was 15.7 ± 10 months. Only 1 surgically treated patient had a post-operative ischemic event, with 13 (93%) showing radiological evidence of collateral within 3 months and 14 (100%) demonstrating adequate revascularisation within 1 year. All patients on whom SPECT scans were performed pre and post-operatively demonstrated marked improvements in perfusion. Conclusion: Appropriately timed indirect revascularisation surgery for childhood moyamoya disease performed in a specialist paediatric centre is a safe and effective technique for managing this condition.
    No preview · Conference Paper · Sep 2014
  • Llewellyn Padayachy · Graham A G Fieggen
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    ABSTRACT: Multiloculated hydrocephalus remains 1 of the most challenging pediatric neurosurgical conditions to treat. Endoscopic membrane fenestration has reduced the shunt revision rate, but adequate communication of the various compartments remains difficult to confirm intraoperatively. We present a novel ultrasound-based intraoperative technique, utilizing an intraventricular microbubble injection technique for assessing the ventricular anatomy and adequacy of membrane fenestration.
    No preview · Article · Aug 2014 · Neurosurgery
  • Llewellyn Padayachy · Graham A G Fieggen · Henri Carrara · Anthony Figaji
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    ABSTRACT: INTRODUCTION: The clinical response of pediatric patients after an ETV remains quite varied. Numerous radiological features correlating with ETV outcome have been described, but there still remains a distinct group of patients in which the outcome of the procedure remains uncertain. METHODS: We reviewed magnetic resonance imaging (MRI) for all ETVs performed between 2008 and 2012 to identify whether a change in the optic nerve sheath diameter (ONSD), as well as the optic nerve to sheath ratio (ONSR), as measured on T2 axial MRI provided a useful radiological marker of ETV outcome. Suitable preoperative and postoperative imaging (acquired within 3 months of the procedure) was necessary for inclusion into the study. The ONSD, as well as the ONSR in both eyes were calculated, and the average change in these parameters was compared to conventional imaging features associated with ETV outcome. These findings were then also correlated with the clinical assessment of ETV outcome. RESULTS: MRI in 21 patients was adequate to measure and calculate the change in ONSD and ONSR, respectively. In successful ETVs (n = 17), the mean change in ONSD was a decrease of 0.9 +/- 0.13 mm, whereas in failed ETVs (n = 4), the mean change was an increase of 0.14 +/- 0.12 mm (P < .02). The ONSR increased from 0.48 to 0.66 (change of 0.22) in successful ETVs and decreased from 0.44 to 0.43 (change of 0.01) in failed ETVs. Change in ONSD of more than 6.1% has a sensitivity of 96% and a specificity of 75% (receiver operating characteristic = 0.75) for ETV outcome. CONCLUSION: Change in optic nerve sheath parameters, specifically ONSD and ONSR, are good independent radiological markers of ETV outcome, but are probably most useful when combined with the historical radiological features of ETV outcome. Copyright (C) by the Congress of Neurological Surgeons
    No preview · Article · Aug 2014 · Neurosurgery

  • No preview · Conference Paper · Jun 2014
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    ABSTRACT: Open spina bifida or myelomeningocele (SBM) is the most common birth defect involving the central nervous system, second only in incidence to congenital cardiac disease. Outcomes in this disorder were poor until the mid-20th century, when modern neurosurgical techniques (closing the lesion and treating hydrocephalus) and treatment for the neuropathic bladder addressed the major causes of mortality, although SBM may still be poorly treated in the developing world. Initial management - or mismanagement - has a profound impact on survival and long-term quality of life.
    No preview · Article · Mar 2014
  • graham fieggen · llewellyn padayachy
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    ABSTRACT: Open spina bifida or myelomeningocele (SBM) is the most common birth defect involving the central nervous system, second only in incidence to congenital cardiac disease. Outcomes in this disorder were poor until the mid-20th century, when modern neurosurgical techniques (closing the lesion and treating hydrocephalus) and treatment for the neuropathic bladder addressed the major causes of mortality, although SBM may still be poorly treated in the developing world. Initial management - or mismanagement - has a profound impact on survival and long-term quality of life.
    No preview · Article · Mar 2014 · South African Medical Journal
  • Llewellyn Padayachy
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    ABSTRACT: The management of patients with myelomeningocele is largely dependent on the timing of the diagnosis, i.e. ante- or postnatally. Antenatal diagnosis can be made using a combination of maternal serum alpha-fetoprotein measurement, fetal ultrasonography and, where necessary, amniocentesis.
    No preview · Article · Mar 2014 · South African Medical Journal
  • Llewellyn C Padayachy · Graham Fieggen

    No preview · Article · Oct 2013 · World Neurosurgery
  • Llewellyn Padayachy · wegoye e

    No preview · Article · Mar 2013 · The S.A. journal of continuing medical education = Die S.A. tydskrif van voortgesette geneeskundige onderrig
  • David Roytowski · Patrick Semple · Llewellyn Padayachy · Henri Carara
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    ABSTRACT: Objectives: Endoscopic third ventriculostomy (ETV) is a routinely used alternative to ventriculoperitoneal shunt in patients with obstructive hydrocephalus. We attempted to determine the usefulness of the surgeon's intraoperative impression and postoperative period intracranial pressure monitoring that may help guide clinicians in predicting the early functional outcome of ETV. Methods: Patients who underwent ETV between 2006 and 2011 were retrospectively reviewed. The sample included 63 patients (23 female and 40 male), between the ages of 13 and 69 years. In each case, the surgeon's intraoperative impression, cerebrospinal fluid (CSF) samplings, and postoperative intracranial pressure (ICP) monitoring (via transduced external ventricular drain for up to 72 hours) was recorded and evaluated in light of functional outcome of ETV at discharge and early follow up (1-2 months). Results: ICP monitoring predicted initial function of the ETV in 51 cases (80.9%) and in 12 cases (19%) suggested ETV failure. Monitoring has a positive predictive value (PPV) of 76.3% and a negative predictive value (NPV) of 100% whereas the surgeon's intraoperative impression of future function had a PPV of 76.5% and NPV of 76.9%. CSF sampling has a much poorer predictive quality because the wide confidence interval and a PPV of 63.6% and NPV 38.2%. In our series the evidence of sepsis as a result of external ventricular drain was found to be 11.67%. Subgroup analysis, removing the patients with posterior fossa tumors, results in increased PPV (85.7%) of ICP monitoring. Conclusions: ETV is a valuable means of treating obstructive hydrocephalus. By considering the surgeon's intraoperative impression and postoperative ICP monitoring course, some of the uncertainty around its functional outcome can be overcome. The surgeon's impression and the ICP monitoring offer approximately the same predictive quality for ETV outcome.
    No preview · Article · Feb 2013 · World Neurosurgery
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    ABSTRACT: The frequency of adverse events, such as cerebral ischemia, following traumatic brain injury (TBI) is often debated. Point-in-time monitoring modalities provide important information, but have limited temporal resolution. This study examines the frequency of an adverse event as a point prevalence at 24 and 72 h post-injury, compared with the cumulative burden measured as a frequency of the event over the full duration of monitoring. Reduced brain tissue oxygenation (PbtO(2) < 10 mmHg) was the adverse event chosen for examination. Data from 100 consecutive children with severe TBI who received PbtO(2) monitoring were retrospectively examined, with data from 87 children found suitable for analysis. Hourly recordings were used to identify episodes of PbtO(2) less than 10 mmHg, at 24 and 72 h post-injury, and for the full duration of monitoring. Reduced PbtO(2) was more common early than late after injury. The point prevalence of reduced PbtO(2) at the selected time points was relatively low (10 % of patients at 24 h and no patients at the 72-h mark post-injury). The cumulative burden of these events over the full duration of monitoring was relatively high: 50 % of patients had episodes of PbtO(2) less than 10 mmHg and 88 % had PbtO(2) less than 20 mmHg. Point-in-time monitoring in a dynamic condition like TBI may underestimate the overall frequency of adverse events, like reduced PbtO(2), particularly when compared with continuous monitoring, which also has limitations, but provides a dynamic assessment over a longer time period.
    No preview · Article · Jun 2012 · Child s Nervous System
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    ABSTRACT: Schistosomiasis is rarely encountered in the United States, but immigration and travel to endemic areas make it important to know its various presentations to improve diagnosis and treatment. We present our experience with a child with Schistosoma haematobium pseudotumor, initially diagnosed as a cord neoplasm.
    No preview · Article · Jul 2011 · The Pediatric Infectious Disease Journal
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    Llewellyn C Padayachy · Anthony A Figaji · M R Bullock
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    ABSTRACT: Introduction Intracranial pressure (ICP) has become a cornerstone of care in adult and pediatric patients with traumatic brain injury (TBI). Discussion Despite the fact that continuous monitoring of ICP in TBI was described almost 60 years ago, there are no randomized trials confirming the benefit of ICP monitoring and treatment in TBI. There is, however, a large body of clinical evidence showing that ICP monitoring influences treatment and leads to better outcomes if part of protocol-driven therapy. However, treatment of ICP has adverse effects, and there are several questions about ICP management that have yet to be definitively answered, particularly in pediatric TBI. This review examines the history and evolution of ICP monitoring, pathophysiological concepts that influence ICP interpretation, ongoing controversies, and the place of ICP monitoring in modern neurocritical care.
    Full-text · Article · Nov 2009 · Child s Nervous System

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