Comparison of Absolute Dose Achievable Between Helical Tomotherapy and RapidArc in Total Dura Mater Irradiation for Child Cancer

Background and Purpose: In this study, the absolute dose achievable between helical tomotherapy (HT) plans and RapidArc (RA) plans for total dura mater irradiation (TDMI) was compared. Materials and methods: A planning study was conducted on nine children's case datasets with dura mater metastasis of neuroblastoma. The target included the entire calvarium and skull base and formed a closed volume with a certain thickness around the brain. HT and RA plans with four coplanar full arcs (RA4) with half-field technique were generated for the comparison of absolute dose achievable. In total, 30.6 Gy was prescribed as D95% (ie, dose to 95% of PTV volume). Results: In the dosimetric comparison between the two modalities, HT provided more homogenous dose distribution than RA4 (mean HI5−95%: 1.046 vs 1.088, P < .001). The V107% and D2Gy of PTV in HT versus RA4 were 3.06% versus 30.47% and 32.59 Gy versus 33.45 Gy, respectively. HT reduced the Dmean and V5Gy of the brain, brainstem, and hippocampus by 25%–48% and 27%–56% compared with RA4, respectively. Conclusion: Both techniques could provide sufficient coverage for targets, but HT offered more homogenous dose to PTV and lower dose to the central region of the brain involving the brainstem and hippocampus. RA4 could be completed in a shorter time with lower MUs, but with relatively higher dose to the brain or hippocampus. In terms of dosimetry, HT may improve long-term cognitive decline in these young pediatric patients with TDMI.

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Long-term clinical and radiographic outcomes after pial pericranial dural revascularization: a hybrid surgical technique for treatment of anterior cerebral territory ischemia in pediatric moyamoya disease

Journal of Neurosurgery Pediatrics ◽

10.3171/2021.2.peds20743 ◽

2021 ◽

pp. 1-9

Author(s):

Alaa Montaser ◽

Jessica Driscoll ◽

Hudson Smith ◽

Madeline B. Karsten ◽

Emily Day ◽

...

Keyword(s):

Dura Mater ◽

Moyamoya Disease ◽

Cerebral Artery ◽

Pediatric Patients ◽

Radiographic Outcomes ◽

Long Term Follow Up ◽

Indirect Revascularization ◽

Burr Holes

OBJECTIVE Isolated anterior cerebral artery (ACA) territory ischemia in pediatric moyamoya disease (MMD) is rare but has been increasingly recognized, particularly in children manifesting progression of disease in a delayed fashion after middle cerebral artery revascularization surgery. Surgical treatment is complicated by limited graft choices, with the small number of case series largely focused on complex, higher-risk operations (omental flap transfers, large interhemispheric rotational grafts); direct bypass (often untenable in children due to vessel size); or, alternatively, the technically simpler method of multiple burr holes (of limited efficacy outside of infants). Faced with the problem of a growing cohort of pediatric patients with MMD that could benefit from anterior cerebral revascularization, the authors sought to develop a solution that was specifically designed for children and that would be lower risk than the more complex approaches adapted from adult populations but more effective than simple burr holes. In this study, the authors aimed to describe the long-term clinical and radiographic outcomes of a novel approach of pial pericranial dural (PiPeD) revascularization, building on the principles of pial synangiosis but unique in using the pericranium and the dura mater as the primary vascular supply, and employing a larger craniotomy with arachnoid dissection to provide robust full-territory revascularization in all ages with reduced risk relative to more complex procedures. METHODS The medical records of all pediatric patients with MMD who presented at a single center between July 2009 and August 2019 were retrospectively reviewed to identify patients with MMD with anterior cerebral territory ischemia. Clinical characteristics, surgical indications, operative techniques, and long-term clinical and radiographic follow-up data were collected and analyzed. RESULTS A total of 25 operations (5.6% of total procedures) were performed in 21 patients (mean age 9.4 years [range 1–16.5 years]; 12 female and 9 male). Almost one-third of the patients had syndromic associations, with no familial cases. Complications included 1 patient (4.7%) with a superficial infection, with no postoperative strokes, hemorrhage, seizures, or deaths. Long-term follow-up was available in 18 of 21 patients (mean 24.9 months [range 4–60 months]). Radiographic engraftment was present in 90.9% (20/22 hemispheres), and no new strokes were evident on MRI on long-term follow-up, despite radiographic progression of the disease. CONCLUSIONS The use of the pericranium and the dura mater for indirect revascularization provided robust vascularized graft with great flexibility in location and high potential for engraftment, which may obviate more complex and higher-risk operations for ACA territory ischemia. Long-term follow-up demonstrated that PiPeD revascularization conferred durable, long-term radiographic and clinical protection from stroke in pediatric patients with MMD. Based on the results of the current study, the PiPeD technique can be considered an additional tool to the armamentarium of indirect revascularization procedures in select pediatric patients with MMD.

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Pediatric bypasses for aneurysms and skull base tumors: short- and long-term outcomes

Journal of Neurosurgery Pediatrics ◽

10.3171/2013.1.peds12444 ◽

2013 ◽

Vol 11 (5) ◽

pp. 533-542 ◽

Cited By ~ 19

Author(s):

Louis J. Kim ◽

Farzana Tariq ◽

Laligam N. Sekhar

Keyword(s):

Skull Base ◽

Saphenous Vein ◽

Pediatric Patients ◽

Graft Patency ◽

Skull Base Tumors ◽

Artery Graft ◽

Short And Long Term ◽

The Mean

Object Cerebral bypass is a useful microsurgical technique for the treatment of unclippable aneurysms and invasive skull base tumors. The authors present the largest reported series of cerebrovascular bypasses in the pediatric population. They describe the short- and long-term clinical and radiographic outcomes of extracranial-intracranial and local bypasses performed for complex cerebral aneurysms and recurrent, invasive, and malignant skull base tumors in pediatric patients. Methods A consecutive series of 17 pediatric patients who underwent revascularization were analyzed retrospectively for indications, graft patency, and neurological outcomes. Results The mean age was 12 years (median 11 years, range 4–17 years), and there were 7 boys (41%) and 10 girls (59%). A total of 18 bypasses were performed in 17 patients and included 10 aneurysm cases (55.5%) and 8 tumor cases (45%). Of these 18 bypasses, there were 11 (61.1%) extracranial-intracranial bypasses (10 saphenous vein grafts [90%] and 1 radial artery graft [10%]), 1 side-to-side anastomosis (5.5%), 2 intracranial reimplants (11.1%), and 4 interposition bypass grafts (22.2%; 2 radial artery grafts, 1 saphenous vein graft, and 1 lingual artery graft). The mean clinical follow-up was 40.5 months (median 24 months, range 3–197 months). The mean radiographic follow-up was 40 months (median 15 months, range 9–197 months). Eighty-two percent of patients (14 of 17) achieved a modified Rankin Scale score between 0 and 2; however, 2 patients died of disease progression during long-term follow-up. The short-term (0- to 3-month) graft patency rate was 100%. Two patients had graft stenosis (11.7%) and underwent graft revisions. Two patients (11.1%) with giant middle cerebral artery aneurysms (> 25 mm) had strokes postoperatively but recovered without a persistent neurological deficit. One patient observed for 197 months showed a stable dysplastic change at the end of the graft. The long-term graft patency was 100% with a mean follow-up of 40 months. There were 2 deaths in the cohort during follow-up; both patients died of malignant tumors (osteogenic sarcoma and chondrosarcoma). Conclusions The authors conclude that in properly selected cases, bypasses can be safely performed in patients with aneurysms and skull base tumors. The bypasses remained patent over long periods of time despite the growth of the patients.

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The Acute Effect of Alcohol on Various Memory Processes

Journal of Psychophysiology ◽

10.1027/0269-8803/a000038 ◽

2010 ◽

Vol 24 (4) ◽

pp. 249-252 ◽

Cited By ~ 7

Author(s):

Márk Molnár ◽

Roland Boha ◽

Balázs Czigler ◽

Zsófia Anna Gaál

Keyword(s):

Low Dose ◽

Short Term Memory ◽

Acute Effect ◽

Long Term Memory ◽

Term Memory ◽

Memory Processes ◽

Different Types ◽

The Brain ◽

Legal Consequences

This review surveys relevant and recent data of the pertinent literature regarding the acute effect of alcohol on various kinds of memory processes with special emphasis on working memory. The characteristics of different types of long-term memory (LTM) and short-term memory (STM) processes are summarized with an attempt to relate these to various structures in the brain. LTM is typically impaired by chronic alcohol intake but according to some data a single dose of ethanol may have long lasting effects if administered at a critically important age. The most commonly seen deleterious acute effect of alcohol to STM appears following large doses of ethanol in conditions of “binge drinking” causing the “blackout” phenomenon. However, with the application of various techniques and well-structured behavioral paradigms it is possible to detect, albeit occasionally, subtle changes of cognitive processes even as a result of a low dose of alcohol. These data may be important for the consideration of legal consequences of low-dose ethanol intake in conditions such as driving, etc.

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