Small Burr Research Articles

A drill technique to suture to the calcified abdominal aorta.

TECHNIQUE Following control of the infrarenal aorta by clamping, a micro drill (Stryker, Kalamazoo, MI, US) is used to produce a series of holes from the inside and outside of the aorta around the sites of the anastomosis to a dacron prosthesis. These holes are spaced 3–4mm apart to avoid disrupting the calcium plaque and weakening the arterial wall. Sutures are passed through each drill hole and reinforced with polytetrafluoroethylene patches to reduce anastomotic bleeding. The technique is illustrated in Figure 1. The hole size can be minimised by using the smallest burr available (eg Stryker’s 0.5mm cross-cut fissure carbide apicoectomy burr).

Surgery for Bilateral Large Intracranial Traumatic Hematomas: Evacuation in a Single Session

ObjectiveManagement guidelines for single intracranial hematomas have been established, but the optimal management of multiple hematomas has little known. We present bilateral traumatic supratentorial hematomas that each has enough volume to be evacuated and discuss how to operate effectively it in a single anesthesia.MethodsIn total, 203 patients underwent evacuation and/or decompressive craniectomies for acute intracranial hematomas over 5 years. Among them, only eight cases (3.9%) underwent operations for bilateral intracranial hematomas in a single session. Injury mechanism, initial Glasgow Coma Scale score, types of intracranial lesions, surgical methods, and Glasgow outcome scale were evaluated.ResultsThe most common injury mechanism was a fall (four cases). The types of intracranial lesions were epidural hematoma (EDH)/intracerebral hematoma (ICH) in five, EDH/EDH in one, EDH/subdural hematoma (SDH) in one, and ICH/SDH in one. All cases except one had an EDH. The EDH was addressed first in all cases. Then, the evacuation of the ICH was performed through a small craniotomy or burr hole. All patients except one survived.ConclusionBilateral intracranial hematomas that should be removed in a single-session operation are rare. Epidural hematomas almost always occur in these cases and should be removed first to prevent the hematoma from growing during the surgery. Then, the other hematoma, contralateral to the EDH, can be evacuated with a small craniotomy.

The effect of TrkA signaling pathway on the expressions of TRPC1，TRPC3 in 6-hydroxydopamine lesioned rat treated by electroacupuncture

Objective: We investigate the effect of TrkA signaling pathway on the expressions of transient receptor potential channel in 6-hydroxydopamine(6-OHDA) lesioned rat treated by electroacupuncture and to explore the role of trkA signaling pathway and TRP subfamily in the pathogenesis of Parkinson's disease (PD), which would reveals the mechanisms of electroacupuncture (EA) neuroprotective effect. Methods: The experimental models were established by unilateral injection of 6-OHDA into the left medial forebrain bundle (MFB).TrkA signaling pathway inhibitor K252a was infected into MFB through two small burr holes in the skull to block trkA signal.The change of TRPC1 and TRPC3 expressions was detected by use of immunohistochemistry and RT-PCR as well as TUNEL for cell apoptosis. Results: The expressions of TRPC1 and TRPC3 in the substantia nigra (SN) of the 6-OHDA lesioned rat were significantly reduced. Compared with PD model group, TRPC1 and TRPC3 expressions were significantly increased in the EA group. There was no statistically significance in TRPC1 and TRPC3 expressions between K252a and PD model groups ( P > 0.05). The number of apoptotic cells in SN increased 54.5% in the PD model rats, while positive apoptotic cells were significantly reduced in the EA group. There was no statistically significance in apoptotic cells between K252a and PD model groups ( P >0.05). Conclusion: TRPC1 and TRPC3 expressions downregulated in the SN of the 6-OHDA lesioned rat, which was accompanied by apoptosis increase in the SN. EA treatment could reverse this effect, and trkA signaling pathway inhibitors K252a can attenuate the neuroprotective effect of EA. It suggested that TRPC1 and TRPC3 may play an important role in the pathogenesis of PD, and certain TRPC subfamily expressions change may be associated with the pathogenesis of PD. Its expression might be subject to trkA signaling pathway, and this signal pathway may be the regulation target for EA neuroprotection.

Burr formation in short hole drilling by ultrasonic assistance

Both in the industry and the service sector, the three aspects of time, costs and quality are among the most important characteristics in the manufacturing. This implies time as well as the costs incurred should be minimalized while preserving the high quality of a product. On top of that, the quality should be high as well. Burr formation has a negative influence on all of these three aspects. In most cases, formed burrs require additional remachining in most cases, leading to higher costs as well. In addition, the quality of the component is also impaired by burr formation.This paper examines to what extent short hole drilling by ultrasonic assistance can reduce burr formation. In order to assess the influence of ultrasound, the vibration amplitude is measured with and without load, depending on the excitation power. Based on these findings, the tests are carried out measuring exit burrs and evaluating them. Results show that the smallest burr values were measured without excitation, yet burr formation tends to decrease again with growing power.

Bone temperature elevation by drilling friction and neurological outcome in the cervical spino-laminoplasty

Drill-induced heat has been suspected as a cause of tissue injury, and there are ample experimental data to substantiate the implication. However, no clinical results have been presented with measurement of temperature in the vicinity of neural structures during the actual spinal procedures. Using a thermocouple, temperature in the gutters drilled in the midline and the lateral margins of the lamina was monitored closely in 61 patients, who underwent the French-door style of cervical spino-laminoplasty. The drilling was performed intermittently for a duration of 5 or 10 seconds, using 3- or 5-mm diamond burrs with sufficient continuous cooling irrigation. The correlations between bone temperature elevation and postoperative sensorimotor symptoms were then analyzed. In the lateral gutters at the most cephalad level (typically C3), where the drilling was performed underneath an overlying bundle of muscle attached to C2's spinous process, the temperature rose significantly. This occurred even with 5-second drilling sessions. The average peak temperature was 44 °C at this level. At all other sites, the temperature was maintained below 40 °C. In three patients, transient neurological deficit developed postoperatively, which did not correlate with the incidence of bone temperature elevation. Intermittent drilling with sufficient irrigation can prevent thermal neuronal damage generated by high-speed drills. Drilling with small diamond burrs in deep and narrow spaces covered by overlying muscles predisposes to inadequate irrigation and thermal elevation. Continuous, protracted drilling without frequent irrigation may result in excessive heat generation and nerve injury.

Modified murine intracranial aneurysm model: aneurysm formation and rupture by elastase and hypertension

IntroductionCerebral aneurysms occur in up to 5% of the population. There are several murine models of aneurysms; however, all have limitations and none reproducibly model aneurysm rupture. To fulfill this...

LOCAL FIBRINOLYSIS IN SURGICAL TREATMENT OF NON-TRAUMATIC INTRACRANIAL HEMORRHAGES

More than 70% of hypertensive hemorrhages are located in deep brain structures. The removal of such hematomas using encephalotomy is accompanied by additional cerebral trauma and often results in unsatisfactory outcomes. The puncture aspiration with local fibrinolysis is one of the minimal invasive methods for treatment of intracerebral hematomas (ICH). The puncture and aspiration of liquid part of ICH (not more than 20% of ICH volume) is performed via small burr hole. Afterward the catheter is placed into ICH cavity and fibrinolytic is injected via this catheter in postoperative period for lysis of ICH solid part. The lysed blood is aspirated within 1-4 days. The last generations of fibrinolytics are very effective concerning intensity of blood clot lysis and practically have no systematic effect on blood coagulation system during their local usage. Morphological examinations showed that usage of fibrinolysis leads to formation of smaller cysts in the region of former hematoma as well as reparative processes in perihemorrhagical zone are expressed better comparing with treatment methods without usage of fibrinolytics. The morphological pattern is also confirmed by clinical signs of neurological deficit regress corresponding to damage focus. We operated 124 patients with parenchymal hemorrhages and 28 patients with intraventricular hemorrhages using described minimally invasive method at the base of Scientific Research Institute of Emergency Care n.a. N. V. Sklifosovsky. The applied method allowed decreasing lethality from 35% to 21% among patients with parenchymal ICH and from 98% to 48%--among patients with ventricular hemotamponade underwent usage of ventricular drainage combined with local fibrinolysis.

Basal Ganglia Hemorrhage: Minimally Invasive and Neuro-Navigation Guided Treatment by Injection of Recombinant Tissue-Type Plasminogen Activator (rtPA)

Objective: Since open surgical evacuation of basal ganglia hemorrhage (BGH) as had been proved did not lead to the desired benefit for the patients, we used minimally invasive clot lysis by injection of recombinant tissue-type plasminogen activator (rtPA). Methods: Patients with spontaneous BGH with or without accompanied intraventricular hemorrhage were included in the study. Following diagnosis of BGH by CT scanning, a catheter was inserted through a small burr hole under neuro-navigation assistance into the centre of hemorrhage and three mg rtPA was injected for three consecutive days. CT scans were performed daily to determine the volume of the hemorrhage. The size of hemorrhage was calculated using the ABCs measuring method. The clinical condition of the patients was classified using the Glasgow coma scale (GCS) and Glasgow outcome scale (GOS). Statistical analysis was performed using the Fisher’s exact test and Chi-square with Yates’ correction. The p-values were calculated with two tails and statistical significance was estimated as p-value <0.05. Results: The procedure was performed on 22 patients (11 females and 11 males). The mean age of the patients was 64 years (range: 44–80 years). Among the patients, 7 (31.8%) were considered in a poor clinical condition, 11 (50%) in an intermediate condition and 4 (18.2%) in a good clinical condition. The total mortality was calculated with n=3 (13.64%). The mean volume of hemorrhage before treatment was 35.14 mL (range 11.5 mL – 67.15 mL). After the third injection, a mean volume reduction of 73.05% could be achieved. Considering the accuracy of the neuro- navigation dataset, correct placement of the drainage in the assumed center of hemorrhage was confirmed in all cases by CT scanning after the first injection. Re-bleeding occurred in 4 cases (18.2%). Conclusion: Treatment with rt-PA in BGH seems an easy, safe and minimally invasive alternative to open surgical hematoma evacuation and it might be more favorable compared to conservative treatment. In our study, we achieved a mean volume of hemorrhage reduction of 73% after 3 days. Clot lysis alone was not the only predictive factor for a better outcome. Outcome prognosis should take several other co-factors into account such as the age of the patient and the GCS at the time of Admission. Large prospective and randomized trials are still necessary to answer these open questions

Neuroprotective effects of focal brain cooling on photochemically-induced cerebral infarction in rats: Analysis from a neurophysiological perspective

Although systemic hypothermia provides favorable outcomes in stroke patients, it has only been adopted in a limited number of patients because of fatal complications. To resolve these issues, focal brain cooling (FBC) has recently drawn attention as a less-invasive treatment for brain injuries. Therefore, we investigated whether FBC has a favorable effect on focal cerebral ischemia (FCI). Male-adult-Wistar rats were used. Under general anesthesia, a small burr hole was made and FCI was induced in the primary sensorimotor area (SI-MI) using photothrombosis. An additional craniotomy was made over the SI-MI and FBC was performed at a temperature of 15°C for 5h. Electrocorticograms (ECoG) were recorded on the border cortex of the ischemic focus. Thereafter, rats were sacrificed and the infarct area was measured. In another experiment, rats were allowed to recover for 5 days after cooling and neurobehavioral function was evaluated. FBC suppressed all ECoG frequency bands during and after cooling (p<0.05), except for the delta frequency band in the precooling versus rewarming periods. The injured areas in the cooling and non-cooling groups were 0.99±0.30 and 1.71±0.54mm2, respectively (p<0.03). The grip strength at 2 days after surgery was preserved in the cooling group (p<0.05). We report the novel finding that epileptiform discharges were suppressed in the ischemic border, the infarct area was reduced and neurobehaviour was preserved by FBC. These results indicate that FBC is neuroprotective in the ischemic brain and has demonstrated therapeutic potential for cerebral infarction.

Morphological Reconstruction Based Segmentation of Lung Fields on Digital Radiographs

Objective To segment lung fields on digital chest radiographs automatically. Methods A morphological reconstruction filter was first applied to the original image to eliminate the local grey level extremes. Then, the Otsu-threshold method was used to segment the whole image into several connected regions, contours of which were then extracted by using a connected components labelling technique. Finally, a morphological closing operator was employed to smooth any small gaps or burrs of the lung field contours. Results Lung fields were segmented for 40 digital chest radiographs, resulting in an accurate segmentation and extraction of their lung fields for most images. Conclusion Integrating a series of algorithms, including morphological reconstruction filtering, Otsu-threshold segmentation, connected components labelling, and morphological operations for smoothing the outlines can effectively segment the lung fields on digital radiographs.

Enchondroma of the Lunate

Enchondroma of the Lunate

Osseous avulsion of adductor longus presenting as incarcerated inguinal hernia

An acute rupture of adductor longus tendon is a rare injury[1]. In most cases, distal insertion of the tendon is involved[2]. The rupture of proximal attachment of the tendon iseven rarer [3].There has been only handful of cases reportedin the literature [4, 5]. Treatment of this ranges from non-operative to complete excision of the muscle [1]. A typicalmechanism of injury is eccentric overload when forcedabduction of the leg occurs during contraction of the adduc-tor muscle group.We describe a case report where an acute onset ofgroin swelling presenting as an incarcerated inguinalhernia was surgically explored by the general surgeons.During the operation, an avulsion of the adductor lon-gus muscle was diagnosed and an immediate repair wasperformed by the orthopaedic surgeons. Informed con-sent was obtained from the patient for the publication ofthis case report.Case reportA 33-year-old male with groin swelling and pain around thegroin presented to general surgeons. This was acute in onsetand was sustained while playing football. The time to pre-sentation from the time of injury was 48 h. There were nogastrointestinal symptoms on presentation. On examination,there was a tender lump around the groin. The lump wasbelow the pubic tubercle. There was no visible bruising. Thelump was irreducible, non-pulsatile and there was no coughimpulse. The surgical team suspected an incarcerated ingui-nal hernia. An ultrasound scan was performed which wasinconclusive for hernia.A surgical exploration of his groin was performed by thegeneral surgeons. At operation, a 3×3-cm mass was found4 cm inferior to the pubic tubercle. Superior to the mass, acavity extended up to the pubis which could easily bepalpated. An avulsion of the attachment of adductor longustendon from the pubis was suspected. They asked for thehelp from orthopaedic team.The bikini line incision in the groin was extended forbetter exposure. Osseous avulsion of adductor longus wasconfirmed. The edge of the tendon was debrided back to ahealthy margin. Soft tissues were elevated form the sym-physis. The periosteum was elevated and a small burr usedto create a bleeding cancellous surface. Two 3.5 bioabsorb-able suture anchors were inserted into the pubis. The sutureswere then passed through the tendon edge and secured (seeFig. 1). The leg was abducted postoperatively to check therepair. Washout of the wound was done and wound wasclosed with interrupted non-absorbable ethilon.Postoperatively, partial weight bearing was allowed for2 weeks followed by weight bearing as tolerated. No abduc-tion beyond neutral was advised for initial 3 weeks followedby strengthening exercises at 6 weeks. He returned to fullactivity with no pain after 3 months.DiscussionThe adductor longus muscle arises from the superior pubicramus and inserts onto the middle part of the linea aspera.The muscle is narrow proximally and expands for a broadinsertion on the femur. The adductor longus is innervated bythe obturator nerve and is involved in the adduction of thehip. Acute tears of the proximal attachment are very rare,and best treatment for these is still debatable. Managementoptions include conservative, surgical excision of the entiremuscle and repair. The recent trend is towards surgical

An investigation on the cutting performance of nano-crystalline diamond coatings on a micro-end mill

In conventional milling, appropriate coatings can be used on tools to enhance their cutting performance and efficiency of the production process. In an effort to improve the tooling performance in micro-scale milling, nano-crystalline diamond films were applied on a micro-end mill by a hot filament chemical vapour deposition process. The cutting performance of the nano-crystalline diamond-coated tool, including cutting forces, tool integrity, surface roughness and burr formation, were evaluated in slot milling of aluminium 6061-T6 against that of an uncoated tool in dry cutting conditions. Reduced cutting forces, free chip adhesion, lower tool wear, improved surface roughness, as well as smaller burrs, were observed using the nano-crystalline diamond-coated tool. The investigation illustrates the possibility of applying nano-crystalline diamond coatings on micro-milling tools for dry cutting and better tooling performance.

Fabrication and characteristics of cube-post microreactors for methanol steam reforming

The lamination-plate structure patterned with microchannels and triangle manifolds regarded as one of the preferred constructions for micro fuel reformers. Learned from the microchannel plate structure, a similar plate structure with cube-post array and triangle manifolds is proposed in this work. A micro-milling process is applied to fabricate the cube posts on the plate surface, and the influences of cutting parameters on the burr formation are analyzed. Experimental results indicate that larger cutting speed, smaller feed rate and cutting depth are in favor of obtaining relatively small burrs. Two plates with different cube-post dimensions and manifold structures are experimentally investigated the performances of methanol steam reforming over the Cu/Zn/Al/Zr catalyst. It indicates that the reactor with small-scale cube posts and acute triangle manifold presents better reforming performances at 260 °C than that of the one with large-scale cube posts and right triangle manifolds. However, their performances are closed to each other at relatively high reaction temperature since the catalyst activity is situated in dominated position at the time.

E-012 Direct transcrainal puncture of a hemangiopericytoma and successful embolization with Onyx

IntroductionHemangiopericytomas (HPC) comprise 1% of intracranial neoplasms and are traditionally treated with preoperative embolization and resection. This is a case of direct transcranial puncture and Onyx embolization of a right...

Intracranial Cysts Containing Cerebrospinal Fluid-Like Fluid: Results of Endoscopic Neurosurgery in a Series of 64 Consecutive Cases

Intracranial cysts containing cerebrospinal fluid (CSF) may be developmental or acquired. To analyze the results of endoscopic neurosurgery in the management of intracranial CSF cysts. In a 7-year period, 64 consecutive patients underwent endoscopic neurosurgery for CSF cysts. Group 1 consisted of 13 patients with acquired cysts; group 2 included 51 patients with developmental cysts. In all cases, the cyst walls were fenestrated through small burr holes with frameless guided operative endoscopes. Follow-up ranged from 1 to 6 years (mean, 3.4 years). There were no mortality and no permanent morbidity, apart from a patient (1.6%) who remained neurologically intact but required ventriculoperitoneal shunting because of intraoperative hemorrhage. The planned fenestrations could be performed in all patients except 2, owing to thick, opaque cyst walls. In group 1, 6 patients fully recovered and remained intact throughout the follow-up, whereas 7 improved but had various degrees of neurological disabilities that were related to their initial diseases. Radiological results were excellent in all cases. In group 2, there were 7 asymptomatic patients who remained unchanged and 44 "symptomatic" patients: 40 (91%) clinically improved, 4 (9%) remained unchanged, and none worsened. Cyst size decreased in 37 patients (74%) and remained unchanged in 13 (26%). In this series, patients of different ages, harboring cysts of various sizes and locations, could be satisfactorily treated with endoscopic neurosurgery.

A study on deburring of magnesium alloy plate by magnetic abrasive polishing

Drilling is one of the most important machining operations in manufacture process. When drilling process is applied, unexpected burrs will be formed on the surface of workpiece. Even a small burr can cause unwanted problems, resulting in low quality products. In order to get better drilled parts, it is very important to know characteristics of burr formation and to remove the burr from the drilled surface with machining process. In this study, magnetic abrasive polishing (MAP) was used to research the deburring factors of magnesium alloy. Moreover, design of experiments was performed to evaluate parameters’ effect on the MAP process. As a result, it was seen that the MAP was useful to remove the burrs on the workpiece without damage from its original surface.

Reconstruction of significant saddle nose deformity using autogenous costal cartilage graft with incorporated mirror image spreader grafts

Reconstruction of significant saddle nose deformity using autogenous costal cartilage graft with incorporated mirror image spreader grafts

δ-Catenin Is Required for the Maintenance of Neural Structure and Function in Mature Cortex In Vivo

Delta-catenin is a brain-specific member of the adherens junction complex that localizes to the postsynaptic and dendritic compartments. This protein is likely critical for normal cognitive function; its hemizygous loss is linked to the severe mental retardation syndrome Cri-du-Chat and it directly interacts with presenilin-1 (PS1), the protein most frequently mutated in familial Alzheimer's disease. Here we examine dendritic structure and cortical function in vivo in mice lacking delta-catenin. We find that in cerebral cortex of 5-week-old mice, dendritic complexity, spine density, and cortical responsiveness are similar between mutant and littermate controls; thereafter, mutant mice experience progressive dendritic retraction, a reduction in spine density and stability, and concomitant reductions in cortical responsiveness. Our results indicate that delta-catenin regulates the maintenance of dendrites and dendritic spines in mature cortex but does not appear to be necessary for the initial establishment of these structures during development.

Do the Quality and Outcomes Framework patient experience indicators reward practices that offer improved access?

The Quality and Outcomes Framework (QOF) includes indicators for patient experience, but there has been little research on whether the indicators identify practices that deliver good patient access. To determine whether practices that achieved high QOF patient experience points in 2005/2006 or 2006/2007 also delivered good patient access. Use of publicly available data to investigate two hypotheses: practices with more positive access survey findings in 2006/2007 will be more likely to have achieved maximum QOF patient experience points in the same year; and practices with maximum QOF patient experience points in 2005/2006 will have higher access survey findings in 2006/2007. Two-hundred and twenty-four East Midlands general practices. For hypothesis one, binary logistic regression was used, with achievement of maximum QOF points as the dependent variable, and access survey findings, responder variables, and practice variables as independent variables. For hypothesis two, general linear models were used, with access survey findings as the independent variables, and achievement of maximum QOF points and the responder and practice variables as dependent variables. The findings did not support the first hypothesis. For the second hypothesis, achievement of maximum QOF points was only significantly associated with patient satisfaction with opening hours (positive correlation). QOF points were not associated with any other aspect of access. The QOF patient experience indicators do not reward practices that offer good patient access. A standard patient survey with financial incentive may be more effective in identifying and rewarding practices that offer better access, including opportunity to book appointments with a particular doctor.