bluuebunny/crossref_metadata_2025 huggingface dataset:
A New Device for Assessing Ankle Dorsiflexion Motion: Reliability and Validity
Authors: Wilken Jason , Rao Smita , Estin Miriam , Saltzman Charles , Yack H. John
Published: April 2011

Study Design

Clinical measurement.

Objective

To determine the validity and reli- ability of measures obtained using a custom-made device for assessing ankle dorsiflexion motion and stiffness.

Background

Limited dorsiflexion has been implicated in the evolution of foot pain in a number of clinical populations. Assessment of ankle dorsiflexion range of motion (ROM) is, therefore, commonly performed as part of a foot and ankle examination. Conventional goniometric assessment methods have demonstrated limited intertester reliability, while alternative methods of measurements are generally more difficult to use. The Iowa ankle range of motion (IAR0M) device was designed in an attempt to develop a simple, clinically relevant, and time- and cost-effective tool to measure ankle dorsiflexion range of motion and stiffness.

Methods

Validity and intertester reliability of dorsiflexion range-of-motion measures using the IAR0M device were assessed at 10,15,20, and 25 Nm of passively applied dorsiflexion torque, with both the knee extended and flexed approxi- mately 20°. Stiffness (change in torque/change in dorsiflexion angle) values were determined using the angular change obtained between the 15- and 25-Nm torque levels. Convergent validity (n = 12) was assessed through comparison of ankle dorsiflexion angles measured simultaneously with the IAR0M device and an optoelectronic motion analysis system. Intertester reliability (n = 17) was assessed by 2 testers who took measurements within the same day.

Results

Validity testing demonstrated excellent agreement (intraclass correlation coefficient [ICC] values ranging from 0.95 to 0.98). Reliability testing demonstrated good to excellent intertester agreement (ICC values ranging from 0.90 to 0.95). The ICCs for ankle joint dorsiflexion stiffness were .71 and .85 for the knee in an extended and flexed position, respectively.

Conclusion

The IAROM device provides valid and reliable measurement of ankle dorsiflexion ROM. The IAR0M device also allows calculation of stiffness by measuring ROM at multiple torque levels, although the reliability of the measurement is not optimal. J Orthop Sports Phys Ther 2011;41(4):274–280. doi:10.2519/jospt.2011.3397
A Canada-US Comparison of Labour Market Outcomes among Highly Educated Immigrants
Authors: Bonikowska Aneta , Hou Feng , Picot Garnett
Published: April 2011

This paper compares changes in relative wages of university educated new immigrant workers in Canada and the United States over the period 1980–2005 and finds that outcomes were generally superior in the United States. Wages of university educated new immigrants declined relative to domestic born university graduates over the study period in Canada but rose between 1990 and 2000 in the United States. The university wage premium for new immigrants was similar in both countries in 1980 but by 2000 was considerably higher in the United States. Accounting for compositional shifts did not alter these basic results.
Phase equilibria studies in alumina-containing high zinc fayalite slags with CaO/SiO2 = 0.55 Part 2
Authors: Zhao Baojun , Hayes Peter C. , Jak Evgueni
Published: April 2011

The phase equilibria and liquidus temperatures in the ZnO„FeO“Al2O3-CaO-SiO2 system have been determined experimentally in equilibrium with metallic iron. Specifically, the effect of Al2O3 concentrations in high zinc fayalite slags is identified and the results are presented in a form of pseudo- ternary sections ZnO„FeO“(Al2O3 + CaO + SiO2) with CaO/SiO2 = 0.55 and (CaO + SiO2)/Al2O3 = 5.0 and 3.5. It was found that in the presence of Al2O3 the spinel phase is formed, and the spinel primary phase field expands and the wustite and melilite primary phase fields are reduced in size with increasing Al2O3 concentration. The implications of the findings to industrial practice are discussed.
Use of a side-cutting aspiration device for resection of tumors during endoscopic endonasal approaches
Authors: Garcia-Navarro Victor , Lancman Guido , Guerrero-Maldonado Amancio , Anand Vijay K. , Schwartz Theodore H.
Published: April 2011

Object

Accessing intra- and extradural tumors via an endonasal approach requires working safely in a relatively narrow area with unobstructed visibility. The authors describe their experience to highlight the utility of a side-cutting aspiration device for endoscopic endonasal resection of skull base tumors.

Methods

The authors used this device in 13 nonconsecutive endoscopic endonasal procedures for different skull base tumors (8 pituitary macroadenomas, 2 craniopharyngiomas, 1 chordoma, 1 recurrent ependymoma, and 1 lymphoma). Illustrative cases and video are presented to demonstrate its use.

Results

The instrument was easy to use and effective in the removal of the lesions presented in this series. In 10 patients (77%), gross-total resection was possible; in the other 3 patients (23%), more than 80% of the tumor was resected. No collateral tissue damage or any other complication resulted from device-related debulking or aspiration.

Conclusions

The side-cutting tissue resector is a safe, easy to use, and effective tool for internal debulking and extracapsular dissection of nonvascularized tumors that are too firm for bimanual suction or blunt ring curette dissection. It is particularly useful when working through a deep and narrow corridor such as is encountered in endoscopic endonasal skull base surgery.
Anxiety responses and neurochemical changes in a kaolin-induced rat model of hydrocephalus
Authors: Hwang Yong Sup , Shim Insop , Chang Jin Woo
Published: April 2011

Object

Hydrocephalus is a pathological enlargement of the ventricles of the brain, which can result from various diseases of the central nervous system. Patients with hydrocephalus frequently show motor abnormalities, such as abnormal gait and posture, as well as intellectual and emotional impairment. The present study was designed to investigate anxiety responses in rats with kaolin-induced hydrocephalus.

Methods

A total of 26 Sprague-Dawley rats were used for this study. Hydrocephalus was induced in 14 Sprague-Dawley rats by injecting 0.1 ml of 20% kaolin solution into the cisterna magna; 12 rats were administered the same volume of saline in the same fashion and served as controls. Seven of the rats that were injected with kaolin and 6 of the rats injected with saline were killed 3 days after injection (Group 1); the remaining rats were killed 4 weeks after injection (Group 2) to evaluate effects related to acute and chronic hydrocephalus. The rats were tested in an elevated plus maze after induction of hydrocephalus by kaolin injection. After the animals were killed, brain sections were immunostained for cholecystokinin and neuropeptide Y. In addition, tyrosine hydroxlyase immunoreactivity in the ventral tegmental area was evaluated by immunohistological staining.

Results

The rats with acute hydrocephalus showed decreased entry into and spent less time in the open arms of the elevated plus maze as compared with the control rats. The hydrocephalic rats had significantly more cholecystokinin-immunoreactive neurons and fewer neuropeptide Y–immunoreactive neurons in their brains. In addition, hydrocephalus progress in this model was positively correlated with the anxiety response. The numbers of tyrosine hydroxlyase–immunoreactive neurons were decreased significantly in the hydrocephalic rats as compared with the control rats.

Conclusions

These results suggest that the rat model of hydrocephalus is characterized by increased anxiety response and is associated with the functional impairment of the central dopamine system.
Morphometric analysis of posterior fossa after in utero myelomeningocele repair
Authors: Grant Ryan A. , Heuer Gregory G. , Carrión Geneive M. , Adzick N. Scott , Schwartz Erin S. , Stein Sherman C. , Storm Phillip B. , Sutton Leslie N.
Published: April 2011

Object

Myelomeningocele (MMC) is characterized by a defect in caudal neurulation and appears at birth with a constellation of neuroanatomical abnormalities, including Chiari malformation Type II. The authors investigated the effects of antenatal versus postnatal repair of MMC through a quantitative analysis of morphometric changes in the posterior fossa (PF).

Methods

The authors retrospectively reviewed the records of 29 patients who underwent in utero MMC repair, 24 patients who underwent postnatal repair, and 114 fetal and pediatric controls. Tonsillar displacement, cerebellum length, pons length, clivus-supraocciput (CSO) angle, and PF area were compared in antenatal and postnatal MMC repair groups as well as in controls without neural tube defects by using t-tests and correlation coefficients.

Results

Initially, the in utero CSO angle was significantly more acute in all patients with MMC—prenatally and postnatally repaired—as compared with controls (57.8° vs 75.4°, p < 0.001); however, the angle rapidly changed and became similar to that in controls between 30 and 31 weeks' gestation to approximately 80°, with antenatal repair having little effect. Postnatally, the CSO angle decreased in controls (R = −0.58) and in the antenatal repair group (R = −0.17). The cerebellum and pons length demonstrated no significant differences in any group. Overall, tonsil descent was corrected in the antenatal repair group as compared with postnatal repair (p < 0.001), and the PF area increased in all 3 groups in utero. Growth was less rapid in patients with MMC compared with controls, but this was corrected by antenatal repair (p = 0.015).

Conclusions

Myelomeningocele was associated with tonsillar herniation and a smaller PF than in control fetuses. Antenatal surgical repair corrected both abnormalities. The CSO angle began significantly more acutely in patients with MMC, but normalized with development regardless of when surgery was performed. Determining the clinical effects of antenatal repair requires further follow-up.
Shunt failure due to intracranial migration of BioGlide ventricular catheters
Authors: Chen Hsin-Hung , Riva-Cambrin Jay , Brockmeyer Douglas L. , Walker Marion L. , Kestle John R. W.
Published: April 2011

Object

In late 2008, the authors recognized a new type of ventriculoperitoneal shunt failure specific to the Bio-Glide Snap Shunt ventricular catheters. This prompted a retrospective review of the patient cohort and resulted in a recall by the FDA in the US.

Methods

After the index cases were identified, the FDA was notified by the hospital, leading to a recall of the product. Hospital operative logs were used to identify patients in whom the affected products were used. A letter describing the risk was sent to all patients offering a free screening CT scan to look for disconnection. A call center was established to respond to patient questions, and an informational video was made available on the hospital website. The authors reviewed the records of the index cases and other cases subsequently identified.

Results

Seven index cases and an additional 16 cases of disconnection were identified in the 466 patients in whom a BioGlide Snap Shunt ventricular catheter had been implanted. Mean time to disconnection was 2.7 years (range 4 days–5.8 years). Computed tomography slices in the plane of the catheter helped visualize disconnections. Retrieval was difficult, and in 5 patients the disconnected catheter was not removable. Three catheters were completely within the ventricle. At presentation, 4 children suffered from severe neurological deficits, including one who died as a result of the shunt malfunction.

Conclusions

BioGlide snap-design ventricular catheters are prone to disconnection. Continued vigilance and specific imaging are important. Catheter removal after disconnection may be difficult. Elective removal prior to disconnection in asymptomatic children has not been performed.
Neurological complications of extracorporeal membrane oxygenation in children
Authors: Hervey-Jumper Shawn L. , Annich Gail M. , Yancon Andrea R. , Garton Hugh J. L. , Muraszko Karin M. , Maher Cormac O.
Published: April 2011

Object

Extracorporeal membrane oxygenation (ECMO) is a potentially life-saving treatment for patients in refractory cardiorespiratory failure. Neurological complications that result from ECMO treatment are known to significantly impact patient survival and quality of life. The purpose of this study was to review the incidence of neurological complications of ECMO in the pediatric population and the role of neurosurgery in the treatment of these patients.

Methods

Data were obtained from the national Extracorporeal Life Support Organization (ELSO) Registry for the years 1990 to 2009. The neurological complications recorded by the registry include CNS hemorrhage, CNS infarction, and seizure. The ECMO Registry at the authors' institution was then searched, and 3 pediatric patients who had undergone craniotomy during ECMO treatment were identified.

Results

Children in the ELSO Registry who were treated with ECMO survived to hospital discharge in 65% of cases. Intracranial hemorrhage occurred in 7.4% of the ECMO-treated patients, with 36% of those surviving to hospital discharge. Hemorrhage was more likely in patients younger than 30 days old and in those requiring ECMO for cardiac indications. Cerebral infarction occurred in 5.7% of all ECMO-treated patients. Clinically diagnosed seizures occurred in 8.4% of all ECMO-treated patients. The ECMO Registry at the authors' institution revealed that 1898 patients were treated there. Intracranial hemorrhage was diagnosed in 81 patients (5.8%), and 3 of these patients were treated with craniotomy. Two of the patients were alive with minimal neurological impairment and normal school performance at 10 and 16 years of follow-up.

Conclusions

Intracranial hemorrhage is a serious complication of ECMO treatment. While the surgical risk is substantial, there may be a role for surgical evacuation of hemorrhage in well-selected patients.
Third ventricular shape: a predictor of endoscopic third ventriculostomy success in pediatric patients
Authors: Foroughi Mansoor , Wong Andrew , Steinbok Paul , Singhal Ash , Sargent Michael A. , Cochrane D. Douglas
Published: April 2011

Object

The criteria for identifying patients in whom endoscopic third ventriculostomy (ETV) provides control of hydrocephalus remain in evolution. In particular, it is not clear when ETV would be effective if intraventricular obstruction is not found preoperatively. The authors postulated that 1) displacement of the third ventricle floor inferiorly into the interpeduncular cistern and displacement of the lamina terminalis anteriorly into the lamina terminalis cistern could predict clinical success of ETV, and 2) improvement in these displacements would correlate with the success of ETV.

Methods

Magnetic resonance imaging in 38 consecutive patients treated between 2004 and 2010 was reviewed to assess displacement of the lamina terminalis and third ventricular floor prior to and following ETV. Displacements of the floor and lamina terminalis were judged qualitatively and quantitatively, using a newly created index, the Third Ventricular Morphology Index (TVMI). The association between the aforementioned morphological features and clinical success of ETV was analyzed.

Results

Ninety-six percent of patients in whom the authors preoperatively observed displacement of the lamina terminalis and the third ventricular floor were successfully treated with ETV. Displacements of the third ventricular floor and lamina terminalis, as judged qualitatively, correlated with the clinical success of ETV. The TVMI correlated with the qualitative assessments of displacement. Postoperative decrease in the TVMI occurred in the majority of successfully treated patients. Changes in third ventricular morphology preceded changes in other measures of third and lateral ventricular volume following ETV.

Conclusions

Assessment of third ventricular floor and lamina terminalis morphology is useful in predicting clinical success of ETV and in the follow-up in treated patients. The TVMI provided a quantitative assessment of the third ventricular morphology, which may be useful in equivocal cases and in research studies.
C-2 neurectomy during atlantoaxial instrumented fusion in the elderly: patient satisfaction and surgical outcome
Authors: Hamilton D. Kojo , Smith Justin S. , Sansur Charles A. , Dumont Aaron S. , Shaffrey Christopher I.
Published: April 2011

Object

The originally described technique of atlantoaxial stabilization using C-1 lateral mass and C-2 pars screws includes a C-2 neurectomy to provide adequate hemostasis and visualization for screw placement, enable adequate joint decortication and arthrodesis, and prevent new-onset postoperative C-2 neuralgia. However, inclusion of a C-2 neurectomy for this procedure remains controversial, likely due in part to a lack of studies that have specifically addressed whether it affects patient outcome. The authors' objective was to assess the surgical and clinical impact of routine C-2 neurectomy performed with C1–2 segmental instrumented arthrodesis in a consecutive series of elderly patients with C1–2 instability.

Methods

Forty-four consecutive patients (mean age 71 years) underwent C1–2 instrumented fusion, including C-1 lateral mass screw insertion. Bilateral C-2 neurectomies were performed. Standardized clinical assessments were performed both pre- and postoperatively. Numbness or discomfort in a C-2 distribution was documented at follow-up. Fusion was assessed using the Lenke fusion grade.

Results

Among all 44 patients, mean blood loss was 200 ml (range 100–350 ml) and mean operative time was 129 minutes (range 87–240 minutes). There were no intraoperative complications, and no patients reported new postoperative onset or worsening of C-2 neuralgia postoperatively. Outcomes for the 30 patients with a minimum 13-month follow-up (range 13–72 months) were assessed. At a mean follow-up of 36 months, Nurick grade and pain numeric rating scale scores improved from 3.7 to 1.0 (p < 0.001) and 9.4 to 0.6 (p < 0.001), respectively. The mean postoperative Neck Disability Index score was 7.3%. The fusion rate was 97%, and the patient satisfaction rate was 93%. All 24 patients with preoperative occipital neuralgia reported relief. Seventeen patients noticed C-2 distribution numbness only during examination in the clinic, and 2 patients reported C-2 numbness, but it did not affect their daily function.

Conclusions

In this series of C1–2 instrumented arthrodesis in elderly patients, excellent fusion rates were achieved, and patient satisfaction was not negatively affected by C-2 neurectomy. In the authors' experience, C-2 neurectomy enhanced surgical exposure of the C1–2 joint, thereby facilitating hemostasis, placement of instrumentation, and decortication of the joint space for arthrodesis. Importantly, with C-2 neurectomy in the present series, no cases of new onset postoperative C-2 neuralgia occurred, in contrast to a growing number of reports in the literature documenting new-onset C-2 neuralgia without C-2 neurectomy. On the contrary, 80% of patients in the present series had preoperative occipital neuralgia and in all of these patients this neuralgia was relieved following C1–2 instrumented arthrodesis with C-2 neurectomy.
Early graft of neural precursors in spinal cord compression reduces glial cyst and improves function
Authors: Boido Marina , Garbossa Diego , Vercelli Alessandro
Published: April 2011

Object

Spinal cord injury (SCI) often results in irreversible and permanent neurological deficits below the injury site and is considered a pathological state of functional damage to local neurons and axon fibers. There are several experimental treatments to minimize tissue damage, and recently cell transplantation has emerged as a promising approach in spinal cord repair. The authors undertook this study to evaluate grafting of neural tube precursors as a possible therapeutic strategy in a model of spinal cord compression in the mouse.

Methods

Compression SCI was induced at the T-13 level in adult male mice. Immediately after injury, neural precursor cells (NPs) were transplanted into the SCI lesion cavity in 18 mice; the remaining 19 mice received saline injections into the lesion cavity and were used as controls. Spinal cords were examined 12, 19, and 26 days postinjury to investigate the survival of the NPs and their effects on the cellular environment, glial scar and glial cyst formation, astrogliosis, and microglial activation.

Results

Grafted NPs survived well and integrated into the host spinal cord tissue. Some NPs had differentiated into cells expressing glial and neuronal markers at all 3 end points. Analysis of glial cyst volume showed a lesion volume reduction of 63.2% in the NP-treated mice compared with volume in the injured but untreated mice. There appeared to be no difference in astroglial and microglial activation between untreated mice and treated ones. Sensory and motor tests demonstrated that transplantation of NPs promoted improvement in injured and treated animals compared with controls.

Conclusions

These results support the therapeutic potential of NPs, demonstrating that they can survive for a long time, differentiate, integrate into the injured spinal cord, and promote functional recovery after SCI.
Pineal region tumors: an optimal approach for simultaneous endoscopic third ventriculostomy and biopsy
Authors: Morgenstern Peter F. , Osbun Nathan , Schwartz Theodore H. , Greenfield Jeffrey P. , Tsiouris Apostolos John , Souweidane Mark M.
Published: April 2011

Object

Simultaneous endoscopic third ventriculostomy (ETV) and tumor biopsy is a widely accepted therapeutic and diagnostic procedure for patients with noncommunicating hydrocephalus secondary to a pineal region tumor. Multiple approaches have been advocated, including the use of a steerable fiberoptic or rigid lens endoscope via 1 or 2 trajectories. However, the optimal approach has not been established based on the individual anatomical characteristics of the patient.

Methods

A retrospective review of patients undergoing simultaneous ETV and tumor biopsy was undertaken. Preoperative MR images were examined to measure the width of the anterior third ventricle and maximal diameters of the tumor, Monro foramen (right), and massa intermedia. The distances between the tumor and massa intermedia, tumor and anterior commissure, midbrain and massa intermedia, and the dorsum sella and anterior commissure were also recorded. Single and dual trajectory approaches were compared using paired t-tests for each parameter.

Results

Over an 8-year interval, 15 patients underwent simultaneous ETV and tumor management. These patients ranged from 6 to 71 years of age (mean 36.7 years); 5 were younger than 18 years of age. Seven were treated using a dual trajectory approach, and 8 were treated using a single trajectory approach. All cases were completed without complications or the need for an additional CSF diversionary procedure within 6 months. The diagnostic yield at biopsy was 86.7%. There were no statistically significant differences between the single and dual trajectory groups for the measured parameters. However, the dual trajectory group demonstrated a larger anterior third ventricular diameter (1.43 vs 1.21 cm, p = 0.29). The single trajectory group trended toward a smaller tumor–anterior commissure interval (2.23 vs 2.51 cm, p = 0.24) and a larger dorsum sella–anterior commissure distance (1.67 vs 1.49 cm, p = 0.28).

Conclusions

These data confirm the safety and diagnostic efficacy of simultaneous ETV and biopsy for tumors of the pineal region. Although no statistically significant differences were seen in the authors' recorded measurements, several trends suggest a role for a tailored approach to selecting a single or dual trajectory approach when using a rigid endoscope.
Early endoscope-assisted hematoma evacuation in patients with supratentorial intracerebral hemorrhage: case selection, surgical technique, and long-term results
Authors: Kuo Lu-Ting , Chen Chien-Min , Li Chien-Hsun , Tsai Jui-Chang , Chiu Hsiu-Chu , Liu Ling-Chun , Tu Yong-Kwang , Huang Abel Po-Hao
Published: April 2011

Object

Currently, the effectiveness of minimally invasive evacuation of intracerebral hemorrhage (ICH) utilizing the endoscopic method is uncertain and the technique is considered investigational. The authors analyzed their experience with this method in terms of case selection, surgical technique, and long-term results.

Methods

The authors performed a retrospective analysis of the clinical and radiographic data obtained in 68 patients treated with endoscope-assisted ICH evacuation. Rebleeding, morbidity, and mortality were recorded as primary end points. Hematoma evacuation rate was calculated by comparing the pre- and postoperative CT scans. Glasgow Coma Scale scores and scores on the extended Glasgow Outcome Scale (GOSE) were recorded at the 6-month postoperative follow-up. The technical aspect of this report explains details of the procedure, the instruments that are used, the methods for hemostasis, and the role of hemostatic agents in the management of intraoperative hemorrhage. The pertinent literature was reviewed and summarized.

Results

All surgeries were performed within 12 hours of ictus, and 84% of the surgeries were performed within 4 hours. The mortality rate was 5.9%, and surgery-related morbidity occurred in 3 cases (4.4%). The hematoma evacuation rate was 93% overall—96% in the putaminal group, 86% in the thalamic group, and 98% in the subcortical group. The rebleeding rate was 1.5%. The mean operative time was 85 minutes, and the average blood loss was 56 ml. The mean GOSE score was 4.9 at 6-month follow-up. The authors acknowledge the limitations of these preliminary results in a small number of patients.

Conclusions

The data suggest that early endoscope-assisted ICH evacuation is safe and effective in the management of supratentorial ICH. The rebleeding, morbidity, and mortality rates are low compared with rates reported in the literature for the traditional craniotomy method. This study also showed that early and complete evacuation of ICH may lead to improved outcomes in selected patients. However, the safety and efficacy of endoscope-assisted ICH evacuation should be further investigated in a large, prospective, randomized trial.
Quality assessment of a new surgical simulator for neuroendoscopic training
Authors: Filho Francisco Vaz Guimarães , Coelho Giselle , Cavalheiro Sergio , Lyra Marcos , Zymberg Samuel T.
Published: April 2011

Object

Ideal surgical training models should be entirely reliable, atoxic, easy to handle, and, if possible, low cost. All available models have their advantages and disadvantages. The choice of one or another will depend on the type of surgery to be performed. The authors created an anatomical model called the S.I.M.O.N.T. (Sinus Model Oto-Rhino Neuro Trainer) Neurosurgical Endotrainer, which can provide reliable neuroendoscopic training. The aim in the present study was to assess both the quality of the model and the development of surgical skills by trainees.

Methods

The S.I.M.O.N.T. is built of a synthetic thermoretractable, thermosensible rubber called Neoderma, which, combined with different polymers, produces more than 30 different formulas. Quality assessment of the model was based on qualitative and quantitative data obtained from training sessions with 9 experienced and 13 inexperienced neurosurgeons. The techniques used for evaluation were face validation, retest and interrater reliability, and construct validation.

Results

The experts considered the S.I.M.O.N.T. capable of reproducing surgical situations as if they were real and presenting great similarity with the human brain. Surgical results of serial training showed that the model could be considered precise. Finally, development and improvement in surgical skills by the trainees were observed and considered relevant to further training. It was also observed that the probability of any single error was dramatically decreased after each training session, with a mean reduction of 41.65% (range 38.7%–45.6%).

Conclusions

Neuroendoscopic training has some specific requirements. A unique set of instruments is required, as is a model that can resemble real-life situations. The S.I.M.O.N.T. is a new alternative model specially designed for this purpose. Validation techniques followed by precision assessments attested to the model's feasibility.
Don't take the plunge: avoiding adverse events with cranial perforators
Authors: Vogel Timothy W. , Dlouhy Brian J. , Howard Matthew A.
Published: April 2011

Object

The object of this study was to evaluate the causes of plunging events associated with automatic-releasing cranial perforators at the authors' institution.

Methods

The authors analyzed a consecutive series of 1652 cranial procedures involving one type of automaticreleasing cranial perforator over a 2-year period. Plunging occurrences were recorded for 2 drill speeds: 1000 rpm in the 1st year and 800 rpm during the 2nd year. Intraoperative observations, neuroimaging studies, and clinical data were evaluated for each plunging event.

Results

The authors identified 9 plunging events for an overall incidence of 0.54%. In the 1st year, they identified 2 plunging events at a speed of 1000 rpm for an incidence of 0.19%. In an effort to reduce this occurrence, the speed of the drill was lowered to 800 rpm. There were 7 additional events, for a significantly increased incidence of 1.16% (p = 0.014, Fisher exact test) after the change was implemented. These cases spanned a number of procedures in adults and pediatric patients, including ventriculostomy placement, craniotomies for tumor resection, tumor biopsy, and endoscopic third ventriculostomy. Despite plunging, no immediate postoperative complications were noted on clinical examination.

Conclusions

While technology continues to improve cranial perforator performance, the use of such a device is still associated with a risk of complications causing dural lacerations and injury to the underlying cortex. Decreasing the drill speed may not decrease the incidence of plunging.
Cervical hybrid arthroplasty with 2 unique fusion techniques
Authors: Cardoso Mario J. , Mendelsohn Audra , Rosner Michael K.
Published: April 2011

Object

Multilevel cervical arthroplasty achieved using the Prestige ST disc can be challenging and often unworkable. An alternative to this system is a hybrid technique composed of alternating total disc replacements (TDRs) and fusions. In the present study, the authors review the safety and radiological outcomes of cervical hybrid arthroplasty in which the Prestige ST disc is used in conjunction with 2 unique fusion techniques.

Methods

After obtaining institutional review board approval, the authors completed a retrospective review of all hybrid cervical constructs in which the Prestige ST disc was used between August 2007 and November 2009 at the Walter Reed Army Medical Center. A Prestige ST total disc replacement was performed in 119 patients. Thirty-one patients received a hybrid construct defined as a TDR and fusion (TDR–anterior cervical decompression and fusion [ACDF]) or as 2 TDRs separated by a fusion (TDR-ACDF-TDR). A resorbable plate and graft system (Mystique) or stand-alone interbody spacer (Prevail) was implanted at the fusion levels. Plain radiographs were compared and evaluated for cervical lordosis, range of motion, implant complications, development of adjacent-level disease, and pseudarthrosis. In addition, charts were reviewed for clinical complications related to the index surgery.

Results

Thirty-one patients (18 men and 13 women; mean age 50 years, range 32–74 years) received a hybrid construct. All patients were diagnosed with radiculopathy and/or myelopathy. Twenty-four patients received a 2-level and 7 a 3-level hybrid construct. In 2 patients in whom a 2-level hybrid construct was implanted, a noncontiguous TDR was also performed. The mean clinical and radiological follow-up duration was 18 months. There was no significant difference in preoperative (19.3° ± 13.3°) and postoperative (19.7° ± 10.5°) cervical lordosis (p = 0.48), but there was a significant decrease in range in motion (from 50.0° ± 11.8° to 38.9° ± 12.7°) (p = 0.003). There were no instances of screw backout, implant dislodgement, progressive kyphosis, formation of heterotopic bone, pseudarthrosis, or symptomatic adjacent-level disease. Seven patients had dysphasia and 1 patient had vocal cord paralysis at 6 weeks. By 3 months, both the dysphasia and the vocal cord paralysis were resolved in all patients.

Conclusions

Hybrid cervical arthroplasty involving the placement of a Prestige ST disc and either the Mystique resorbable plate or Prevail stand-alone interbody device is a safe and effective alternative to multilevel fusion for the management of cervical radiculopathy and myelopathy.
The tree as evolutionary icon: TREE in the Natural History Museum, London (William T. Stearn Prize 2010)
Authors: Hellström Nils Petter
Published: April 2011

As part of the Darwin celebrations in 2009, the Natural History Museum in London unveiled TREE, the first contemporary artwork to win a permanent place in the Museum. While the artist claimed that the inspiration for TREE came from Darwin's famous notebook sketch of branching evolution, sometimes referred to as his “tree of life” drawing, this article emphasises the apparent incongruity between Darwin's sketch and the artist's design – best explained by other, complementary sources of inspiration. In the context of the Museum's active participation in struggles over science and religion, the effect of the new artwork is contradictory. TREE celebrates Darwinian evolutionism, but it resonates with deep-rooted, mythological traditions of tree symbolism to do so. This complicates the status of the Museum space as one of disinterested, secular science, but it also contributes, with or without the intentions of the Museum's management, to consolidate two sometimes conflicting strains within the Museum's history. TREE celebrates human effort, secular science and reason – but it also evokes long-standing mythological traditions to inspire reverence and remind us of our humble place in this world.
Archibald Menzies on Albemarle Island, Galápagos archipelago, 7 February 1795
Authors: Charles Nelson E. , Porter Duncan M.
Published: April 2011

Menzies made the earliest extant botanical collections in the Galápagos; five sheets, representing three endemic species, are known. Menzies's own account of the visit is also extant and is transcribed here from his manuscript journal.
Identification of Coagulase-Negative Staphylococci Isolated from Continuous Ambulatory Peritoneal Dialysis Fluid using 16s Ribosomal RNA, tuf, and SodA Gene Sequencing
Authors: Shin Jeong Hwan , Kim Si Hyun , Jeong Haeng Soon , Oh Seung Hwan , Kim Hye Ran , Lee Jeong Nyeo , Yoon Young Chul , Kim Yang Wook , Kim Yeong Hoon
Published: April 2011

Introduction

Coagulase-negative staphylococcus (CoNS) is the most common pathogen in continuous ambulatory peritoneal dialysis (CAPD)–associated peritonitis. There is no well-organized, standardized database for CoNS, and few studies have used gene sequencing in reporting species distribution in CAPD peritonitis. In the present study, we used 3 housekeeping genes to evaluate the prevalence of CoNS isolated from CAPD peritonitis episodes and to estimate the accuracy of, and the characteristic differences between, these genes for species identification.

Methods

All 51 non-duplicated CoNS isolates obtained from CAPD peritonitis between April 2006 and May 2008 were used. The strains were identified by polymerase chain reaction and by direct sequencing using the 16S ribosomal RNA (rRNA), tuf, and sodA genes. We determined species distribution, and using selected databases, we analyzed the characteristics and diagnostic utility of the individual genes for species identification.

Results

In GenBank (National Institutes of Health, Bethesda, MD, USA), we found 49 type or reference strains for CoNS 16S rRNA, 17 for tuf, and 46 for sodA, and we used those data for sequence-similarity comparisons with CAPD isolates. Among our 51 strains, S. epidermidis (66.7%) was the most common, followed by S. haemolyticus (11.8%), S. warneri (7.8%), S. caprae (5.9%), S. capitis (3.9%), and S. pasteuri (2.0%). For 1 strain, different species results were obtained with each gene. The identification rates with 16S rRNA, sodA, and tuf gene sequencing were 84.0%, 96.0%, and 92.2% respectively. The discrimination capability of 16S rRNA gene was lower in a few individual species, and for the sodA gene, the percentage similarity to sequences from reference strains was also lower. The tuf gene had excellent identification capacity, but relatively few type strains are available in public databases. The 16S rRNA gene did not discriminate between S. caprae and S. capitis. The sodA gene showed a similarity rate that was lower than that for sequences of the 16S rRNA gene. The tuf type strain sequences for S. caprae and S. pasteuri are not available in public databases.

Conclusions

The sodA, tuf, and 16S rRNA genes were very useful for CoNS identification. Each has its own characteristics of similarity, discriminative power, and inclusion in databases.
Initial Observations using a Novel “Cine” Magnetic Resonance Imaging Technique to Detect Changes in Abdominal Motion Caused by Encapsulating Peritoneal Sclerosis
Authors: Wright Benjamin , Summers Angela , Fenner John , Gillott Richard , Hutchinson Charles E. , Spencer Paul A. , Wilkie Martin , Hurst Helen , Herrick Sarah , Brenchley Paul , Augustine Titus , Bardhan Karna D.
Published: April 2011

Encapsulating peritoneal sclerosis (EPS) is an uncommon complication of peritoneal dialysis (PD), with high mortality and morbidity. The peritoneum thickens, dysfunctions, and forms a cocoon that progressively “strangulates” the small intestine, causing malnutrition, ischemia, and infarction. There is as yet no reliable noninvasive means of diagnosis, but recent developments in image analysis of cine magnetic resonance imaging for the recognition of adhesions offers a way forward. We used this protocol before surgery in 3 patients with suspected EPS. Image analysis revealed patterns of abdominal movement that were markedly different from the patterns in healthy volunteers. The volunteers showed marked movement throughout the abdomen; in contrast, movement in EPS patients was restricted to just below the diaphragm. This clear difference provides early “proof of principle” of the approach that we have developed.
Risk Factors Associated with Encapsulating Peritoneal Sclerosis in Dutch Eps Study
Authors: Korte Mario R. , Sampimon Denise E. , Lingsma Hester F. , Fieren Marien W. , Looman Caspar W.N. , Zietse Robert , Weimar Willem , Betjes Michiel G.H. , Boer W.H. , van den Dorpel M.A. , van Ittersum Rotterdam; F.J. , Konings C.J. , Krediet R.T. , de Sevaux R.G.L. , Zanen A.L.
Published: April 2011

Objective

Encapsulating peritoneal sclerosis (EPS) is a serious complication of peritoneal dialysis (PD) with a multifactorial pathophysiology and possible increasing incidence. The aim of the present study was to evaluate the independent associations of PD duration, age, dialysis fluids, and kidney transplantation with EPS.

Methods

A multicenter case–control study was performed in the Netherlands from 1 January 1996 until 1 July 2007. The population comprised 63 patients with EPS and 126 control patients. Control patients were selected from the national registry and were matched for date of PD start. Associations were analyzed using a log linear regression model. Primary outcome was appearance of EPS.

Results

Compared with control patients, patients with EPS were younger at the start of PD (34.7 ± 15.4 years vs. 51.5 ± 14.7 years, p < 0.0001). The cumulative period on PD was longer in EPS patients than in control patients (78.7 ± 37.8 months vs. 32.8 ± 24 months, p < 0.0001), and the cumulative period on icodextrin was also longer in EPS patients (32.7 ± 23.3 months vs. 18.1 ± 15.7 months, p = 0.006). Compared with control patients, more EPS patients underwent kidney transplantation (47 vs. 59, p < 0.0001). With regard to the period after transplantation, the yearly probability of EPS increased in the year after transplantation to 7.5% from 1.75%. In multivariate regression analysis, cumulative PD duration, age at PD start, transplantation, time from last transplantation to EPS, calendar time, time on icodextrin, and ultrafiltration failure were independently associated with EPS. Transfer from PD to hemodialysis for reasons other than suspected EPS could not be identified as a risk factor for EPS.

Conclusions

Duration of PD, age at PD start, kidney transplantation, time since last transplantation, ultrafiltration failure, and time on icodextrin were associated with a higher risk of EPS.
Impact of Arterial Stiffness on Adverse Cardiovascular Outcomes and Mortality in Peritoneal Dialysis Patients
Authors: Sipahioglu Murat H. , Kucuk Hamit , Unal Aydin , Kaya Mehmet G. , Oguz Fatih , Tokgoz Bulent , Oymak Oktay , Utas Cengiz
Published: April 2011

Background

Cardiovascular (CV) disease is a major cause of morbidity and mortality in patients with end-stage renal disease. In recent years, arterial stiffness has taken on great importance in the pathophysiology of CV diseases. The independent predictive value of arterial stiffness for CV events and for all-cause and CV mortality has been demonstrated in the general population and in hemodialysis patients. Our aim in this study was to determine the relationship of arterial stiffness with mortality and fatal and nonfatal CV events in peritoneal dialysis (PD) patients.

Methods

In this prospective observational cohort study with 2 years of follow-up, we studied a cohort of 156 PD patients with a mean follow-up of 19.2 ± 6.4 months. At baseline, echocardiography and standard clinical and biochemical analyses were performed in all patients and in 28 healthy subjects. Aortic stiffness index beta (ASIβ, a surrogate marker of arterial stiffness) was calculated as follows: ASIβ = ln (systolic blood pressure / diastolic blood pressure) / [(systolic diameter – diastolic diameter) / diastolic diameter].

Results

During the follow-up period, 25 of the patients (16.0%) died, and 10 of those deaths had CV causes. Nonfatal CV events occurred in 15 patients. The median ASIβ was greater in PD patients than in control subjects (4.2 vs. 3.5; interquartile range: 3.2 – 5.5 vs. 2.5 – 4.8; p = 0.028]. In the fully adjusted multivariate Cox regression analysis (covariates: age, sex, albumin, hemoglobin, diabetes mellitus, comorbid CV disease, left ventricular mass index, residual glomerular filtration rate, dialysate-to-plasma ratio of creatinine, Kt/V urea, left ventricular ejection fraction, duration of dialysis, smoking), ASIβ independently predicted fatal and nonfatal CV events (hazard ratio: 1.239; 95% confidence interval: 1.103 to 1.392), but not all-cause mortality.

Conclusions

Our results provide the first direct evidence that arterial stiffness is an independent risk predictor of adverse CV outcome in PD patients.
Mutations in Gp41 are Correlated with Coreceptor Tropism but Do Not Improve Prediction Methods Substantially
Authors: Thielen Alexander , Lengauer Thomas , Swenson Luke C , Dong Winnie WY , McGovern Rachel A , Lewis Marilyn , James Ian , Heera Jayvant , Valdez Hernan , Harrigan P Richard
Published: April 2011

Background

The main determinants of HIV-1 coreceptor usage are located in the V3-loop of gp120, although mutations in V2 and gp41 are also known. Incorporation of V2 is known to improve prediction algorithms; however, this has not been confirmed for gp41 mutations.

Methods

Samples with V3 and gp41 genotypes and Trofile assay (Monogram Biosciences, South San Francisco, CA, USA) results were taken from the HOMER cohort ( n=444) and from patients screened for the MOTIVATE studies ( n=1,916; 859 with maraviroc outcome data). Correlations of mutations with tropism were assessed using Fisher's exact test and prediction models trained using support vector machines. Models were validated by cross-validation, by testing models from one dataset on the other, and by analysing virological outcome.

Results

Several mutations within gp41 were highly significant for CXCR4 usage; most strikingly an insertion occurring in 7.7% of HOMER-R5 and 46.3% of HOM-ER-X4 samples (MOTIVATE 5.7% and 25.2%, respectively). Models trained on gp41 sequence alone achieved relatively high areas under the receiver- operating characteristic curve (AUCs; HOMER 0.713 and MOTIVATE 0.736) that were almost as good as V3 models (0.773 and 0.884, respectively). However, combining the two regions improved predictions only marginally (0.813 and 0.902, respectively). Similar results were found when models were trained on HOMER and validated on MOTIVATE or vice versa. The difference in median log viral load decrease at week 24 between patients with R5 and X4 virus was 1.65 (HOMER 2.45 and MOTIVATE 0.79) for V3 models, 1.59 for gp41-models (2.42 and 0.83, respectively) and 1.58 for the combined predictor (2.44 and 0.86, respectively).

Conclusions

Several mutations within gp41 showed strong correlation with tropism in two independent datasets. However, incorporating gp41 mutations into prediction models is not mandatory because they do not improve substantially on models trained on V3 sequences alone.
The prevalence of psoriasis among elderly individuals: more questions than answers
Authors: Bassukas Ioannis D. , Mavridou Konstantina A. , Evangelou Theocharis , Gaitanis Georgios
Published: April 2011

Knowledge of epidemiological data of psoriasis among elderly people is limited. Herein the prevalence of psoriasis among non-permanently hospitalized, elderly (70-89 year old) individuals was assessed by a face-to-face interview using a structured questionnaire adapted from an earlier telephone survey elsewhere. 450 individuals 70-89 years old consented to contribute. Psoriasis was found in 15/450 individuals [life-long prevalence: 3.33%; (95% confidence intervals: 1.99-5.47%)]; 1/450 individuals have ever required systemic treatment (0.2% [0.01-1.4%]). This prevalence is about ten times higher than corresponding results of the aforementioned telephone survey with the same questionnaire. In conclusion this study: i) Provides the first estimation of psoriasis prevalence in Greece, albeit focused in a particular age group and demonstrates a relatively high life-long prevalence, however with minimal morbidity among older people; ii) Underscores the need for studies to evaluate the impact of proxy effects (e.g. telephone information) in assessing skin morbidity of older probands.
Systemic Meglumine Antimoniate in Acute Cutaneous Leishmaniasis: Children versus Adults
Authors: Layegh Pouran , Rahsepar Sara , Rahsepar Amir Ali
Published: April 2011

Some studies showed that children have a lower response to systemic use of pentavalent antimoniate than adults. We aimed to evaluate the response rate to Glucantime therapy in children and compare it with adults. One hundred and twelve patients with acute cutaneous leishmaniais (ACL) were divided into two equal groups of adults (> 15 yrs) and children (≤ 15 yrs). They received meglumine antimoniate; 20 mg/kg/day for 20 days, their improvement rate was evaluated 20 and 45 days after treatment. Perprotocol analysis showed a significantly lower response in the children group 20 and 45 days after initiation of the treatment (P = 0.0001, 95% confidence interval [CI] = 0.190 [0.079–0.456]/P = 0.0051, 95% CI = 0.317 [0.140–0.717], respectively). Moreover, after intention-to-treat analysis, the same results were seen in the younger group 20 and 45 days after treatment (P = 0.0003, 95% CI = 0.228 [0.098–0.528]/P = 0.0132, 95% CI = 0.382 [0.177–0.825], respectively). According to our results, systemic Glucantime has lower efficacy in treating ACL in children than adults.