bluuebunny/crossref_metadata_2025 huggingface dataset:
Three Gorges Dam Project: An Introduction
Authors: Acharya Pranav
Published: May 2009

The Three Gorges Dam Project (TGDP) on the Yangtze River in Hubei Province is touted as the long term solution to China’s increasing energy and agricultural needs. TGDP, with a 1084 km2 reservoir of 39.3 billion m3 capacity, will be the largest multipurpose water conservancy project ever built in the world. The main structures of the project are dam, hydropower stations and navigation facilities. After studying fifteen alternative sites and approval of Environmental Impact Statement (EIS) in February 1992, the construction of the dam began in 1994 with an expected duration of 17 years.

Annual reduction of 40-50 million tons of coal consumption by providing 85 billion kilowatt hours of electricity, protection of 1.6 million hectares of agricultural land from floods and considerable improvement of navigation and tourism sector are the major anticipated benefits of TGDP. However, the proposed benefits put significant pressure on ecological and socio-cultural environment of the TGDP area. Relocation and resettlement of over 1.3 million local populations, inundation of several sites of historical importance, deforestation and loss of biodiversity including several endangered species of flora and fauna across a region of 58,000 km2, increased sedimentation, water pollution and potential earthquake risks are the major adverse consequences of TGDP.

Key words: Three Gorges Dam Project (TGDP), environmental impacts, alternatives, resettlement, biodiversity, ecology, China

Hydro Nepal: Journal of Water, Energy and Environment Vol. I, Issue No. 1 (2007) pp. 54-56
Hydropower, a Good Alternative for Nepal: Challenges and Approaches
Authors: Garcia John C.
Published: May 2009

Although Hydropower development is a good option for Nepal, there are serious challenges to the successful construction and operations of such facilities. This article briefly addresses why hydropower development is appropriate for Nepal as well as some of the more important social and environmental challenges. The author also makes suggestions to approach these challenges.

Key words: Hydropower; social and environmental impacts; landslides; sediments; biodiversity; poverty alleviation; fisheries; compliance; community relations; reporting; Nepal

Hydro Nepal: Journal of Water, Energy and Environment Vol. I, Issue No. 1 2007, pp. 7-14
Hydropower Development in Nepal: Lessons from Past Models
Authors: Pun Santa Bahadur
Published: May 2009

In the last six decades since the 1951 overthrow of Rana regime, hydropower development in Nepal was implemented under various models depending on the donors. The 1950s and ‘60s were the era of bilateralism to be subsumed by multilateralism of the 1970s and ‘80s only to be trodden over by liberalization and privatization of the 1990s and 2000. If one were to scrutinize these bilateral, multilateral and liberalized models in the hydropower sector closely, certain interesting patterns emerge. Nepal could well learn lessons from them. Hydro Nepal: Journal of Water, Energy and Environment Issue No. 2, (2008) pp. 5-8
A Decade of Legally Practicing the Environmental Assessment Tool
Authors: Uprety Batu Krishna
Published: May 2009

Two and half-decades of experience in implementing environmental assessment (EA) tools through policies and legislations have contributed to integrating environmental aspects into development projects in Nepal. The Enforcement of Environment Protection Act (EPA) of 1996 and the Environment Protection Rules (EPR) of 1997 have expanded the application of EA tools for the prescribed proposals. After the enforcement of EPA and EPR, the government has approved the EIA reports of 72 projects. In 2006 alone, EIA reports of 22 projects were approved. In general, however, approval of EIA reports has no meaning unless they are effectively implemented. The benefits of EA could be realised after environmental monitoring and auditing that helps to know the level of compliance and effectiveness of mitigation measures. This article outlines the causes of delay decision and major initiatives taken to make the EA more effective, realistic and practical.

Hydro Nepal: Journal of Water, Energy and Environment Vol. 1, No. 2(2008) pp. 13-16
The Future of Large Dams: Dealing with Social, Environmental, Institutional and Political Costs
Authors: Mathur Hari Mohan
Published: May 2009

Not available
Paraguay, Bhutan and Nepal: Landlocked but Hydropower Rich Cases of the Lame duck, Flying Goose and Sitting Duck!
Authors: Pun Santa Bahadur
Published: May 2009

Paraguay has 5.6 million people, Bhutan has 0.6 million and Nepal has 27 million, all small land locked countries with rich hydropower potential. The 12,600 MW Itaipu Project commissioned on Paraguay-Brazil border river, Parana, was the world’s largest hydropower plant until China’s Three Gorges superseded it in 2007. Paraguay’s share, half of Itaipu’s generation, is on average of about 44,000 million units annually with over 90% sold to Brazil. Nepal’s projected average annual generation from three major multipurpose projects, at Sapta Koshi, Karnali Chisapani and Pancheshwar’s 50%, totals about the same. Despite two decades of such large volume of power export, however, Paraguay remains the second poorest country in South America. Nepal, with a tiny 550 MW of hydropower capacity, is undergoing bouts of load shedding and is mired in controversies. Bhutan, with a mere export of about 1,300 MW, comprising 60% of the national revenue, has therefore been strongly recommended as the model for Nepal to replicate. If India is to maintain her 9% GDP growth rate then she will require 785,000 MW (6 times the present installed capacity) of power by 2026/27. Along with this demand for power, she will also need huge quantities of additional freshwater. While there are options for power, there are none for water. All large or small storage projects in Nepal augment water to the rivers flowing down to India. So far India’s policy has been to obtain this augmented water through Nepal’s default. Nepal needs to seriously consider why Paraguay, despite its huge export, is a lame duck while Bhutan with a tiny export is a flying goose!Key words: Power export, Karnali Chisapani, Pancheshwar, Sapta Koshi, Nepal-India Water Resources negotiations,Nepal’s default, Paraguay, Bhutandoi: 10.3126/hn.v3i0.1895Hydro Nepal: Journal of Water, Energy and Environment Issue No. 3, January, 2008 Page 4-8
An Opportunities-Based Approach to Mitigating Risks Associated with Infrastructure Development Projects
Authors: Messerschmidt Don
Published: May 2009

‘Risk' is a major point of focus in the literature on resettlement and reconstruction associated with the impacts of major infrastructure development on project affected individuals and families. Previous approaches to risk appear to emphasize the negative consequences of development, and it is no wonder then that project affected people often emphatically resist development and change. This paper proposes that a more pro-active, positive opportunities and benefits approach be taken in dealing with resettlement and reconstruction associated with large scale infrastructure projects. The discussion is focused on the eight ‘risk factors' (or ‘opportunity factors'?) listed in the well known ‘Impoverishment Risk and Reconstruction' (IRR) Model. Three more such factors are added to the list based on field experience in South Asia. The point is that by emphasizing the potential opportunities and benefits, project affected people are more likely to be supportive of projects that may disrupt their lives. Key words: Resettlement, opportunities, risk, IRR model, South Asia, infrastructure development  doi: 10.3126/hn.v3i0.1912 Hydro Nepal: Journal of Water, Energy and Environment Issue No. 3, January, 2008 Page 9-15
The Kosi Pralaya; Could the Catastrophe have been Averted? And What Next?
Authors: Pun Santa Bahadur
Published: May 2009

The Kosi river breached its eastern embankment at Kushah in Nepal on August 18, 2008 causing havoc and misery to over 50,000 Nepalese and 2.5 million Indians in the state of Bihar. The affected people lost their homes, farmlands and livelihoods. Four months after the disaster, the affected people are still living in plastic tents in winter. Due to the impact of this catastrophe on the more industrialized and prosperous eastern Nepal, the overall effect on the country’s economy has been severe. At the time of the breach, the river was actually below the level of normal discharge. There was no big flood in Kosi. This was not Nature’s wrath but simply human failings. Bihar’s Water Resources Minister, Vijender Yadav, admitted “The breach happened due to lackadaisical maintenance of the embankment’, but laid the blame on the “previous government”. With timely action such a disaster could have been averted. Saif Uddin Soz, India’s Union Minister for Water Resources, has already said publicly that “Kosi is in focus this time in particular … our main interest is flood control and irrigation,” a statement that puts focus on implementation of the Sapta Kosi High Dam in Nepal. This dam will be built at a great social and environmental cost to the Nepalese people due to submergence of limited fertile valleys, displacement of large number of villagers and over 300 km of very large link canals from both banks of the dam (Kosi-Mechi and Kosi-Ghagra Links) to the Indian border. The attraction to Nepal is, of course, the 3,300 MW of power it will make available for export. The Sapta Kosi High Dam needs to wait until the vital 13-year pending issues of the “signed, sealed and done” 6,720 MW Pancheshwar Multipurpose Project on the Mahakali are finalized.Key words: Kosi Catastrophe; Sapta Kosi high dam; Kosi barrage; flood; NepalHydro Nepal: Journal of Water, Energy and Environment Issue No. 4, January, 2009 Page 2-7
Some Features of China’s Small Hydropower
Authors: Jiandong Tong
Published: May 2009

China developed small hydropower (SHP) with its own resources instead of importing advanced technology from other countries. SHP has been instrumental in rural electrification. In 1997, SHP accounted for 28.6% of whole exploitable hydro energy in China. The peculiarities of SHP of China are:1. Decentralized approach for SHP development with county as basic unit,2. Special policies and strategies adopted- self construction, self management and self consumption- rural hydropower development fund set up - levy of 2 cents of each kWh- electricity generates electricity policy3. Various Channels of investment are mobilizedTo exploit China's experience in SHP the International Network on Small Hydropower (IN-SHP) was established in Hangzhou, China.Hydro Nepal: Journal of Water, Energy and Environment Issue No. 4, January, 2009 Page 11-14
Putting a Price-Tag on Humanity: Development-Forced Displaced Communities’ Fight for More than Just Compensation
Authors: Maldonado Julie Koppel
Published: May 2009

The impoverishment commonly associated with development-induced displacement often occurs because of government and development agencies’ reliance on compensation as a remedy for resettlement. This study focuses on the inadequacy of compensation use in development-induced forced displacement and resettlement by analyzing 50 recent development projects that involved forced displacement. The aim is for increased understanding leading to action to lessen the impoverishing effects of development-induced displacement.Hydro Nepal: Journal of Water, Energy and Environment Issue No. 4, January, 2009 Page 18-20
How Movements Move? Evaluating the Role of Ideology and Leadership in Environmental Movement Dynamics in India with Special Reference to the Narmada Bachao Andolan
Authors: Nepal Padam
Published: May 2009

Lawrence Cox (1999) has argued that the established perspectives on social movements operate with an inadequately narrow conception of the ‘object’ that is being studied and thus tends to ‘reify’ “movements” as usual activity against essentially static backgrounds, and in its place, he advocates a concept of social movement as the more or less developed articulation of situated rationalities. Following Cox, therefore, the present study perceives social movements as articulations of situated rationalities by perceiving them as a tactical, dialectical response to the harsh realities of the political system. This would help us capture the essential dynamic and transformative aspects of the movement. Any social movement, and for that matter, environmental movements are characterized by the presence of agencies and structural components, which, however, are not a priori and static. They are rather dynamic and get changed and transformed in the course of the movement. Precisely for this reason, the environmental movements can at best be comprehended by way of locating and analyzing the dynamism and transformations of the movements produced by the dialectical interaction of the various components and parameters of the movement over a span of time. Hence, the present paper aims to evaluate the dynamics and transformations of the environmental movements in India, taking the case of the Narmada Bachao Andolan, and, adopting a strategic relational approach within the agent-structure framework as its framework of analysis. For the present purpose, however, we have taken only two variables, namely, Ideology and Leadership and attempted the analysis of their contributions in producing movement dynamics.Hydro Nepal: Journal of Water, Energy and Environment Issue No. 4, January, 2009 Page 24-29
Rural Entrepreneurship through Electricity
Authors: Pandey Ram Chandra
Published: May 2009

Rural electrification in Nepal is supported mostly by bilateral donors and banks as a top down supply driven activity with emphasis on generation and transmission, but not focusing on supplying electricity to the maximum number of rural people. In the past, rural electrification was awarded as political favors, leading to inefficiency. Further, it could not further the efficient development of energy, which requires marketing innovation. The result of such rural power distribution created a condition where everybody was at fault and a loser. An innovative approach involving the rural communities has the potential of reversing this trend, and allowing communities themselves to manage local rural electrification systems. This approach has raised public interest in Community Development and Rural Electrification with the establishment of about 450 rural electricity communities in Nepal. In anticipation, these communities are willingly contributing 20% matching fund of total rural electrifi cation cost. Since 2003 to 2008, 189,770 households (about 45,000 households annually) have gotten access to electricity in rural areas through the promotion of community-based electricity development. Clearly, this is a signifi cant positive response from the rural population. Like community forestry before it, community rural electrifi cation is also a success story in Nepal. The new approach has paved the way to gender equality. It helped to generate more economic activities, to activate productive end use of electricity, developed rural entrepreneurship and released the poorest of poor population from the ‘bonds’ of the old social structure.Hydro Nepal: Journal of Water, Energy and Environment Issue No. 4, January, 2009 Page 36-39
A Successful Model for Community - Managed Program Implementation
Authors: Supply Rural Water
Published: May 2009

Presentation by Rural Water Supply and SanitationFund Development BoardHydro Nepal: Journal of Water, Energy and Environment Issue No. 4, January, 2009 Page 52-53
An Interview with Mr. Sriranjan Lacoul, Director General, Department Of Electricity Development (DOED), Government of Nepal
Authors: Thanju Jeewan P
Published: May 2009

Not AvailableHydro Nepal: Journal of Water, Energy and Environment Issue No. 4, January, 2009 Page 54-55
An Interview with Mr. Uttar Kumar Shrestha
Authors: Bashyal Shankar
Published: May 2009

Mr. Uttar Kumar Shrestha granted an interview to Mr. Shankar Bashyal of HYDRO Nepal. Excerpts from an interviewHydro Nepal: Journal of Water, Energy and Environment Issue No. 4, January, 2009 Page 59-61
Bologna in America: The Spellings Commission and neo-liberal higher education policy
Authors: Greenwood Davydd J.
Published: May 2009

This article summarises/analyses the higher education reforms proposed by the 'Spellings Commission' in the United States on quality assurance and accountability, and draws attention to the links I see between these reform proposals and the Bologna Process. I trace a brief history of the Spellings Commission and analyse it in order to produce questions for discussion about the 'parallel' processes of reform in higher education in the U.S. and Europe.
A 1- to 4-year follow-up review of treatment of sciatica using chemonucleolysis or laminectomy
Authors: Javid Manucher J.
Published: May 2009

✓ To help clarify the comparative effects of chemonucleolysis and discectomy, the author studied 178 consecutive patients with sciatica who did not respond to conservative treatment. None had previously undergone laminectomy or chemonucleolysis or had spinal stenosis. All received postmyelography computerized tomography (CT) and, if the radiological interpretation was that of an extruded migrated disc, a laminectomy was performed; otherwise, the patient was given a choice of the two procedures. Of the 178 patients, 106 underwent chemonucleolysis and 72 laminectomy. Workers' compensation was being paid to 21.6% of the chemonucleolysis patients and 20.8% of the laminectomy patients.

Postoperatively, substantial improvement was noted in 82.7% of the chemonucleolysis patients and 92.5% of the laminectomy patients at 6 weeks and in 92.8% of the chemonucleolysis patients and 89.7% of the laminectomy patients at 6 months. The majority of patients in both groups had improved neurological signs. Follow-up questionnaires at 1 to 4 years postoperatively revealed an overall success rate of 86.5% for chemonucleolysis patients and 83.8% for laminectomy patients. In patients not receiving workers' compensation, 90.1% of the chemonucleolysis patients and 88.6% of the laminectomy patients had a successful outcome; in those receiving workers' compensation, 69.6% of the chemonucleolysis patients and 60.0% of the laminectomy patients had a successful outcome. No statistically significant differences in improvement rate in neurological symptoms or signs were identified between the two procedures. Overall, 85.1 % of the chemonucleolysis patients and 78.5% of the laminectomy patients were employed at follow-up review.

To achieve optimum results and eliminate noncandidates for chemonucleolysis, routine use of postmyelography CT is recommended. When properly used, chymopapain chemonucleolysis is an acceptable alternative to surgical discectomy.
Nerve transfer in brachial plexus traction injuries
Authors: Samardzic Miroslav , Grujicic Danica , Antunovic Vaso
Published: May 2009

✓ Brachial plexus palsy due to traction injury, especially spinal nerve-root avulsion, represents a severe handicap for the patient. Despite recent progress in diagnosis and microsurgical repair, the prognosis in such cases remains unfavorable. Nerve transfer is the only possibility for repair in cases of spinal nerve-root avulsion. This technique was analyzed in 37 patients with 64 reinnervation procedures of the musculocutaneous and/or axillary nerve using upper intercostal, spinal accessory, and regional nerves as donors. The most favorable results, with an 83.8% overall rate of useful functional recovery, were obtained in patients with upper brachial plexus palsy in which regional donor nerves, such as the medial pectoral, thoracodorsal, long thoracic, and subscapular nerves, had been used. The overall rates of recovery for the spinal accessory and upper intercostal nerves were 64.3% and 55.5%, respectively, which are significantly lower. The authors evaluate the results of nerve transfer and analyze different donor nerves as factors influencing the prognosis of surgical repair.
The extended frontal approach to tumors of the anterior, middle, and posterior skull base
Authors: Sekhar Laligam N. , Nanda Anil , Sen Chandra N. , Snyderman Carl N. , Janecka Ivo P.
Published: May 2009

✓ The extended frontal approach is a modification of the transbasal approach of Derome. The addition of a bilateral orbitofrontal or orbitofrontoethmoidal osteotomy improves the exposure of midline lesions of the anterior, middle, and posterior skull base, while minimizing the need for frontal lobe retraction. The authors present a 5-year experience with 49 patients operated on via the extended frontal approach. In seven patients, the extended frontal approach was used alone; in the remaining 42, it was combined with other skull base approaches. Highly malignant tumors were removed en bloc, whereas benign tumors and low-grade malignancies were removed either en bloc or piecemeal. Reconstruction was usually performed using fascia lata, a pericranial flap, and/or autologous fat. A temporalis muscle flap or a distant microvascular free flap was required for some patients.

One patient died 1 month postoperatively due to superior mesenteric artery thrombosis. Three patients had postoperative infections, two had cerebrospinal fluid leaks requiring reoperation, and four had brain contusions or hematomas. All but two patients recovered to their preoperative functional level. After an average follow-up period of 26 months (range 6 to 56 months), 64% of patients with benign lesions, 64% of patients with low-grade malignancies, and 44% of patients with high-grade lesions were alive with no evidence of disease.
Effect of head elevation on intracranial pressure, cerebral perfusion pressure, and cerebral blood flow in head-injured patients
Authors: Feldman Zeev , Kanter Malcolm J. , Robertson Claudia S. , Contant Charles F. , Hayes Christopher , Sheinberg Michael A. , Villareal Cynthia A. , Narayan Raj K. , Grossman Robert G.
Published: May 2009

✓ The traditional practice of elevating the head in order to lower intracranial pressure (ICP) in head-injured patients has been challenged in recent years. Some investigators argue that patients with intracranial hypertension should be placed in a horizontal position, the rationale being that this will increase the cerebral perfusion pressure (CPP) and thereby improve cerebral blood flow (CBF). However, ICP is generally significantly higher when the patient is in the horizontal position. This study was undertaken to clarify the issue of optimal head position in the care of head-injured patients. The effect of 0° and 30° head elevation on ICP, CPP, CBF, mean carotid pressure, and other cerebral and systemic physiological parameters was studied in 22 head-injured patients. The mean carotid pressure was significantly lower when the patient's head was elevated at 30° than at 0° (84.3 ± 14.5 mm Hg vs. 89.5 ± 14.6 mm Hg), as was the mean ICP (14.1 ± 6.7 mm Hg vs. 19.7 ± 8.3 mm Hg). There was no statistically significant change in CPP, CBF, cerebral metabolic rate of oxygen, arteriovenous difference of lactate, or cerebrovascular resistance associated with the change in head position. The data indicate that head elevation to 30° significantly reduced ICP in the majority of the 22 patients without reducing CPP or CBF.
Prognostic significance of magnetic resonance imaging in the acute phase of cervical spine injury
Authors: Schaefer Dale M. , Flanders Adam E. , Osterholm Jewell L. , Northrup Bruce E.
Published: May 2009

✓ Fifty-seven patients with acute cervical spine injuries and associated major neurological deficit were examined within 2 weeks of injury by magnetic resonance (MR) imaging. All patients had abnormal scans, indicating intramedullary lesions. This study was undertaken to determine if the early MR imaging pattern had a prognostic relationship to the eventual neurological outcome. Three different MR imaging patterns were observed in these patients: 21 patients had patterns characteristic of intramedullary hematoma (Group 1); 17 had intramedullary edema over more than one spinal segment, but no hemorrhage (Group 2); and 19 had restricted zones of intramedullary edema involving one spinal segment or less (Group 3).

The neurological state was determined using standard motor index scores at admission and at follow-up examination. Characteristically, the patients in Group 1 had admission motor scores significantly lower than the other two groups. At follow-up examination, the median percent motor recovery was 9% for Group 1, 41% for Group 2, and 72% for Group 3.

These studies suggest that the MR imaging pattern observed in the acutely injured human spinal cord has a prognostic significance in the final outcome of the motor system. It is only when an accurate prognosis can be given at the outset that useful treatment data might be collected for homogeneous injury groups, and accurately based long-term planning made for the best patient care.
Lobar intracerebral hemorrhage
Authors: Wakai Susumu , Kumakura Nahomi , Nagai Masakatsu
Published: May 2009

✓ The authors operated consecutively on 50 patients with lobar intracerebral hemorrhage during a prospectively designed study period from January, 1986, to March, 1990. They investigated the correlations between the underlying causes and the clinicoradiographic features in 29 patients who showed no angiographic vascular abnormalities, in order to elucidate the operative indication for such cases. Patients with ruptured saccular aneurysm or trauma were not included in this study. There were 15 males and 14 females, ranging in age from 7 to 76 years (mean 52.4 years). Histological diagnoses of the surgical specimens were as follows: vascular malformation in nine cases (arteriovenous malformation (AVM) in six and cavernous malformation in three), microaneurysm in 11, cerebral amyloid angiopathy in six, and brain tumor in two; in the remaining case the cause was not verified histologically. The underlying cause was determined in 96.5% of cases. The mean patient age was lowest in the cavernous malformation group (27.0 years), followed by the AVM (45.8 years), microaneurysm (59.8 years), and cerebral amyloid angiopathy (70.0 years) groups. Four patients with vascular malformation (three AVM's and one cavernous malformation) had previous episodes of bleeding at the same site, whereas none of those with microaneurysms or cerebral amyloid angiopathy had such episodes. On computerized tomography (CT) scans, the round to oval hematoma was related to the presence of an AVM or cavernous malformation in contrast to microaneurysms and cerebral amyloid angiopathy. Upon infusion of contrast material, variable enhancement was seen in five (two AVM's and three cavernous malformations) of the nine vascular malformations while no enhancement was noted in any patient with microaneurysm or cerebral amyloid angiopathy at the acute stage. Subarachnoid extension of the hematoma was associated with cerebral amyloid angiopathy significantly more frequently than with AVM's (p < 0.05) and microaneurysms (p < 0.01).

The results suggest that clinicoradiographic pictures in cases with negative angiography are quite different among the three major pathological categories; namely, vascular malformation (AVM and cavernous malformation), microaneurysm, and cerebral amyloid angiopathy. It is suggested that the underlying etiology of a given lobar intracerebral hemorrhage with negative angiography may be predicted by a combination of patient age, history of previous bleeding at the same site, hematoma shape, and subarachnoid extension of the hematoma on CT scans. Based upon these findings, the authors discuss operative indications for such cases.
An analysis of the venous drainage system as a factor in hemorrhage from arteriovenous malformations
Authors: Miyasaka Yoshio , Yada Kenzoh , Ohwada Takashi , Kitahara Takao , Kurata Akira , Irikura Katsumi
Published: May 2009

✓ The authors studied the venous drainage system and its impairment in relation to risk of hemorrhage in 108 cases of supratentorial arteriovenous malformation (AVM). The proportion of AVM's undergoing hemorrhage (hemorrhagic rate) was calculated in relation to: 1) the number of draining veins (one, two, or three or more); 2) the presence or absence of impairment in venous drainage (severe stenosis or occlusion in draining veins); and 3) the location of draining veins (deep venous drainage alone, superficial venous drainage alone, or a combination of the two). Statistical analysis demonstrated that AVM's with the following characteristics had a high risk of hemorrhage: 1) one draining vein (hemorrhagic rate 89% in 54 patients); 2) severely impaired venous drainage (hemorrhagic rate 94% in 18 patients); and 3) deep venous drainage alone (hemorrhagic rate 94% in 32 patients).

The present study suggests that the venous drainage system of AVM's is significantly associated with the risk of hemorrhage of these lesions. Therefore, careful preoperative angiographic evaluation of the venous drainage system is mandatory for decision making in the management of patients with AVM's.
Changes in major phospholipids of mitochondria during postischemic reperfusion in rat brain
Authors: Nakahara Ichiro , Kikuchi Haruhiko , Taki Waro , Nishi Syogo , Kito Makoto , Yonekawa Yasuhiro , Goto Yasunobu , Ogata Nobuyoshi
Published: May 2009

✓ Major mitochondrial phosopholipids were examined in rat brain after 30 minutes of reperfusion following 30- or 60-minute periods of ischemia to examine their changes and explore their relationship to mitochondrial dysfunction during postischemic reperfusion. The amount of phospholipids and the percentage of polyunsaturated fatty acid chains, which tended to decrease during 30 minutes of ischemia, recovered after reperfusion. However, after ischemia lasting for 60 minutes, these parameters did not recover but decreased further, suggesting progressive disruption of phospholipids by phospholipase A2 after reperfusion. These changes were particularly notable in cardiolipin, which is contained specifically in mitochondria. The changes were also closely associated with mitochondrial respiration and respiratory enzyme (cytochrome c oxidase and F0F1-adenosine triphosphatase) activities, which have been known to correlate with the amount of cardiolipin. These results suggest that phospholipid metabolism in mitochondrial membranes is an important factor bearing on the integrity of energy metabolism during postischemic reperfusion.
Regeneration of calvarial defects by a composite of bioerodible polyorthoester and demineralized bone in rats
Authors: Solheim Eirik , Pinholt Else M. , Bang Gisle , Sudmann Einar
Published: May 2009

✓ A study was performed to evaluate regeneration of defects in rat calvaria either unfilled or filled with a bioerodible polyorthoester only, demineralized bone only, or a composite of both. At 4 weeks, histological and radiographic studies showed that defects filled with a composite of bioerodible polyorthoester and demineralized bone or demineralized bone alone were bridged by bone. Unfilled defects or defects filled with polyorthoester only did not heal. The polyorthoester caused slight inflammation that subsided by 3 weeks, and only traces of the filler could be detected at 4 weeks. The polyorthoester provided local hemostasis when used either alone or in composites with demineralized bone. The composite implant was moldable, easily contoured, and technically easier to use than demineralized bone alone.
Tension pneumocephalus associated with rupture of a middle fossa encephalocele
Authors: Cartwright Mont J. , Eisenberg Mark B.
Published: May 2009

✓ Acquired nontraumatic (spontaneous) encephaloceles of the middle fossa are not common. Rupture of an encephalocele frequently leads to a cerebrospinal fluid fistula. Tension pneumocephalus consequent to rupture of an encephalocele has not been previously reported, but conceivably occurs by means of a ball-valve mechanism in the ensuing fistulous tract. An unusual case is presented of an elderly man who suffered acute life-threatening neurological symptoms from a tension pneumocephalus that likely developed from rupture of an acquired nontraumatic encephalocele of the left middle fossa. The symptoms correlated with the location of the intracranial abnormalities. The literature is reviewed and the pathophysiology of the lesion is discussed.
Stenosis of the axis and cervical myelopathy
Authors: Prakash Shankar G. , Chandy Mathew J. , Abraham Jacob
Published: May 2009

✓ A rare case is described of marked segmental stenosis of the axis secondary to developmental hypertrophy of the posterior neural arch causing cervical myelopathy. The patient made a remarkable recovery following decompressive laminectomy.
The relationship of blood flow velocity fluctuations to intracranial pressure B waves
Authors: Newell David W. , Aaslid Rune , Stooss Renate , Reulen Hans J.
Published: May 2009

✓ Intracranial pressure (ICP) and continuous transcranial Doppler ultrasound signals were monitored in 20 head-injured patients and simultaneous synchronous fluctuations of middle cerebral artery (MCA) velocity and B waves of the ICP were observed. Continuous simultaneous monitoring of MCA velocity, ICP, arterial blood pressure, and expired CO2 revealed that both velocity waves and B waves occurred despite a constant CO2 concentration in ventilated patients and were usually not accompanied by fluctuations in the arterial blood pressure. Additional recordings from the extracranial carotid artery during the ICP B waves revealed similar synchronous fluctuations in the velocity of this artery, strongly supporting the hypothesis that blood flow fluctuations produce the velocity waves. The ratio between ICP wave amplitude and velocity wave amplitude was highly correlated to the ICP (r = 0.81, p < 0.001). Velocity waves of similar characteristics and frequency, but usually of shorter duration, were observed in seven of 10 normal subjects in whom MCA velocity was recorded for 1 hour. The findings in this report strongly suggest that B waves in the ICP are a secondary effect of vasomotor waves, producing cerebral blood flow fluctuations that become amplified in the ICP tracing, in states of reduced intracranial compliance.
Early seizures after mild closed head injury
Authors: Lee Shih-Tseng , Lui Tai-Ngar
Published: May 2009

✓ The authors review the seizure incidence in 4232 adult patients with mild closed head injury who did not receive prophylactic anticonvulsant agents. One hundred patients (2.36%) experienced seizures within 1 week after head injury; 43 of these (1.02% of the series) had seizures within 24 hours after trauma. Most of the seizures (84%) that developed during the 1st week after injury were of the generalized tonic-clonic type. The incidence of generalized tonic-clonic seizures was higher than that of partial seizures with motor symptoms both within 24 hours (91% vs. 9%) and during the Day 2 to 7 period (79% vs. 21%). No definite intracranial pathological findings were detected by computerized tomography (CT) in 53% of patients with early posttraumatic seizures; six patients had intracranial hemorrhage without intracranial parenchymal damage (three with epidural hematoma and three with subarachnoid hemorrhage). The most common positive CT findings in the early posttraumatic-seizure group were intracerebral hemorrhage (24%), followed by acute subdural hematoma with intracerebral hemorrhage (17%). Intracerebral parenchymal damage could be identified on CT scans in 41 (48.8%) of 84 patients with generalized tonic-clonic seizures and five (31%) of 16 patients with partial seizures with motor symptoms. The intracerebral parenchymal damage was most commonly detected in the frontal lobe (21%) and the temporal lobe (19%). Seven patients with early posttraumatic seizures received emergency craniotomy to remove an intracranial hematoma (epidural in three, subdural and intracerebral in four) because the mass effect resulted in significant midline shift as seen on CT scans. This review suggests that early posttraumatic seizures after mild closed head injury have a high incidence (53%) in patients with normal CT scan findings. Although the possibility of surgically correctable intracranial hemorrhage is low (7%), the condition may be devastating if not treated properly.
Diffuse brain swelling in severely head-injured children
Authors: Aldrich E. Francois , Eisenberg Howard M. , Saydjari Christy , Luerssen Thomas G. , Foulkes Mary A. , Jane John A. , Marshall Lawrence F. , Marmarou Anthony , Young Harold F.
Published: May 2009

✓ In this study, data were prospectively collected from 753 patients (111 children and 642 adults) with severe head injury and examined for evidence of diffuse brain swelling and its association with outcome. Diffuse brain swelling occurred approximately twice as often in children (aged 16 years or younger) as in adults. A high mortality rate (53%) was found in these children, which was three times that of the children without diffuse brain swelling (16%). Adults with diffuse brain swelling had a mortality rate (46%) similar to that of children, but only slightly higher than that for adults without diffuse brain swelling (39%). When the diagnosis of diffuse brain swelling was expanded to include patients with diffuse brain swelling plus small parenchymal hemorrhages (< 15 cu cm), these mortality rates were virtually unchanged.
Intraforaminal repair of plexus spinal nerves by a posterior approach: an experimental study
Authors: Kline David G. , Donner Thomas R. , Happel Leo , Smith Barbara , Richter Hans P.
Published: May 2009

✓ Many spinal nerve roots injured due to stretch or other types of lesions are not reparable. Some spinal nerves might be repaired if they could be exposed in their intraforaminal course. A posterior subscapular approach for a more lateral exposure of the brachial plexus was combined with a facetectomy to expose intraforaminal nerves in a series of Macaca rhesus monkeys. This approach exposed a 6- to 10-mm segment of spinal nerve not approachable by a more classic anterior operation. Sural grafts were placed from the dural exit of the spinal nerves to the cord level of the plexus. Nine surviving animals were followed for 36 to 54 months and observed for clinical evidence of return of function. In each animal at least one electromyogram (EMG) was performed. The plexus was then re-exposed and intraoperative nerve action potentials were recorded across graft sites. Evoked muscle action potential and cortical potentials were recorded in six animals.

Despite the proximal level of repair, adequate regeneration was shown by clinical, electrical, and histological studies. Functional return was best to the supraspinatus and biceps muscles and to wrist and finger flexors. Clinical recovery was present, but less effective, for deltoid, wrist, and finger extensors and intrinsic muscles of the hand, despite evidence on EMG of reinnervation. Recovery of the infraspinatus muscle was poor. Nerve action potentials could be recorded across each graft site. Reinnervational activity was recorded by EMG and evoked muscle action potential studies in most of the muscles studied, despite the persistence of some denervational changes 3 years or more after injury and repair. Histological studies confirmed the presence of a large number of axons of moderate size and myelination even at the forearm level.
Perfusion pressure breakthrough threshold of cerebral autoregulation in the chronically ischemic brain: an experimental study in cats
Authors: Sakaki Toshisuke , Tsujimoto Shozaburo , Nishitani Masaya , Ishida Yasuhito , Morimoto Tetsuya
Published: May 2009

✓ A study was designed to investigate hyperperfusion syndrome after the restoration of normal cerebral blood flow in a chronically cerebral ischemic state resulting from high-flow arteriovenous malformations or severe carotid stenosis. A fistula between the left distal common carotid artery and the jugular vein was created and the left vertebral artery was simultaneously occluded in 44 cats to produce a chronic cerebral ischemic state. For control experiments, 10 cats underwent occlusion of the left common carotid and vertebral arteries. Six weeks later, pial arterial behavior, disruption of the blood-brain barrier (BBB), and cerebral histological changes were investigated using three experimental methods. In the first, in which a fistula was occluded under normal conditions, pial arteries contracted to some 80% of the resting state; however, no BBB disruption or histological changes were observed. In the second experiment, in which a 20-minute occlusion of the left middle cerebral artery was performed in the cats with a patent fistula, a 30% to 40% dilated state of the pial arteries continued after recirculation, and BBB disruption-induced cerebral edema and infarction were observed. These findings were more prominent in the cats that underwent occlusion of the fistula. On the other hand, in the control group, the pial arteries returned to resting size within 40 minutes, and no BBB disruption or histological changes were observed. In the third experiment, in which moderate hypertension was induced for 1 hour, the pial arteries dilated much more remarkably; BBB disruption and cerebral edema were revealed to be more extensive in the cases of fistula occlusion than within those with a patent fistula. In the control group, however, the pial arteries contracted 10% during hypertension, while BBB disruption and histological changes were not evident. The results indicate that the perfusion pressure breakthrough threshold in the chronically ischemic brain may not be reduced by the restoration of normal blood flow, but may be decreased by the addition of new ischemic insults or hypertension.
Effect of mannitol on local cerebral blood flow after temporary complete cerebral ischemia in rats
Authors: Shirane Reizo , Weinstein Philip R.
Published: May 2009

✓ The effects of pretreatment with mannitol on local cerebral blood flow (CBF) after permanent or temporary global cerebral ischemia were evaluated with 14C-iodoantipyrine autoradiography in rats under halothane-N2O endotracheal anesthesia. Blood pressure, pulse rate, arterial blood gas levels, and electroencephalographic (EEG) tracings were monitored throughout the experiments. After permanent occlusion of the basilar artery and both external carotid and pterygopalatine arteries, severe global ischemia was induced by permanent occlusion of the common carotid arteries (CCA's) or by a 30-minute temporary CCA occlusion followed by 5 minutes of reperfusion. Intravenous mannitol (25%, 1 gm/kg) or saline solution was administered 5 minutes before occlusion of the CCA's. Cerebral blood flow was measured in 24 anatomical regions.

The EEG tracings flattened within 2 to 3 minutes after the onset of ischemia, and no recovery was observed during reperfusion. In the mannitol-treated rats and the saline-treated controls, autoradiographic studies after permanent occlusion showed no CBF in the forebrain or cerebellum, although brain-stem and spinal cord CBF values were normal. After 5 minutes of reperfusion, CBF in the cortex, basal ganglia, and white matter was 100% to 200% higher in mannitol-treated rats and 50% to 100% higher in saline-injected rats than in the nonischemic anesthetized control group. Heterogeneously distributed areas of no-reflow were seen in all saline-injected rats but were observed in none of the mannitol-treated rats. Pretreatment with mannitol prevented postischemic obstruction of the microcirculation during 5 minutes of recirculation after 30 minutes of severe temporary ischemia, but the EEG signals did not recover. Further studies of the functional and morphological responses to longer periods of postischemic recirculation are needed to verify the extent to which these mannitol-induced effects are protective.
Multidrug resistance gene expression in pediatric primitive neuroectodermal tumors of the central nervous system
Authors: Tishler David M. , Weinberg Kenneth I. , Sender Leonard S. , Nolta Jan A. , Raffel Corey
Published: May 2009

✓ Pediatric primitive neuroectodermal tumor (PNET) is a malignancy of the central nervous system currently treated with surgery, radiation therapy, and chemotherapy. Despite aggressive management, tumors recur in almost one-half of all patients. Drug resistance of tumor cells may, in part, explain the poor outcome. Resistance to chemotherapeutic agents may be related to expression of the multidrug resistance gene (MDR1) and its protein product, P-glycoprotein.

The role of MDR1 in 16 instances of PNET was investigated using Western blot analysis to detect the expression of P-glycoprotein, messenger ribonucleic acid (mRNA), polymerase chain reaction to detect MDR1 mRNA expression, and Southern blot analysis to assess gene amplification. Analysis of proteins extracted from 15 tumors revealed that two of the 15 patients expressed detectable levels of P-glycoprotein. Polymerase chain reaction of ribonucleic acid from 12 PNET's revealed that six of the 12 patients (four of 10 de novo tumors and both recurrent tumors) expressed MDR1 mRNA. Southern blot analysis of deoxyribonucleic acid from 16 PNET's revealed no evidence of MDR1 amplification in any tumor. This is the first report of MDR1 expression in pediatric brain tumors. These data suggest a possible role for MDR1 in de novo and acquired drug resistance in PNET's.
Resolution of petrous internal carotid artery stenosis after transluminal angioplasty
Authors: Rostomily Robert C. , Mayberg Marc R. , Eskridge Joseph M. , Goodkin Robert , Winn H. Richard
Published: May 2009

✓ Percutaneous transluminal angioplasty is commonly used for treatment of peripheral vascular disease, but only recently has it been applied to craniocervical lesions. The successful use of percutaneous transluminal angioplasty for treatment of an isolated high-grade stenosis of the petrous internal carotid artery is described in a patient with progressive ischemic symptoms despite maximum medical management. At his 2-year follow-up examination, the patient remained asymptomatic with angiographic evidence of progressive resolution of the stenotic lesion and indirect evidence of improved hemispheric blood flow ipsilateral to the lesion. Percutaneous transluminal angioplasty may provide an effective means of treatment for selective intracranial atherosclerotic stenosis.
Direct approach to a traumatic giant internal carotid artery aneurysm associated with a carotid-cavernous fistula
Authors: Masana Yoshiyuki , Taneda Mamoru
Published: May 2009

✓ The case is reported of a giant intracranial internal carotid artery aneurysm associated with a carotid-cavernous fistula following a closed head injury. The aneurysm and the fistula disappeared after only the neck of the aneurysm was clipped. This is the first case in which a direct surgical approach was successful in sparing the internal carotid flow. Reports of similar cases are reviewed.
Cerebral protection during aneurysm surgery with isoflurane anesthesia
Authors: Meyer Fredric B. , Muzzi Donald A.
Published: May 2009

✓ A strategy for intraoperative cerebral protection is described in which intraoperative electroencephalography is used to titrate the level of inspired isoflurane given for anesthesia to obtain isoelectricity prior to temporary vessel occlusion during repair of difficult aneurysms. During temporary vessel occlusion, arterial blood pressure is maintained or increased with an inotropic or vasopressor agent. After clipping of the aneurysm, the concentration of isoflurane is reduced to allow the patient to awaken in the operating room for early postoperative neurological examination. The combination of a high concentration of isoflurane, temporary vessel occlusion, and maintenance of arterial blood pressure may be a useful protective regimen during neurovascular procedures.
Two examples of ancient skull surgery
Authors: Froeschner Elsie H.
Published: May 2009

✓ The author, while a research illustrator at the Smithsonian Institution National Museum of Natural History, studied two ancient skulls from the Incan period in Peru, both with trephination. Her conclusions and illustrations of the skulls are included in this paper.