Standard X-ray Films Research Articles

Effect of critical shoulder angle on deltoid muscle strength reduction in patients with rotator cuff tears

To investigate the synergistic interaction between the deltoid muscle and the rotator cuff muscle group in patients with rotator cuff tears (RCT), as well as the impact of the critical shoulder angle (CSA) on deltoid muscle strength. A retrospective analysis was conducted on clinical data from 42 RCT patients who met the selection criteria and were treated between March 2022 and March 2023. There were 13 males and 29 females, with an age range of 42-77 years (mean, 60.5 years). Preoperative visual analogue scale (VAS) score was 6.0±1.6. CSA measurements were obtained from standard anteroposterior X-ray films before operation, and patients were divided into two groups based on CSA measurements: CSA>35° group (group A) and CSA≤35° group (group B). Handheld dynamometry was used to measure the muscle strength of various muscle group in the shoulder (including the supraspinatus, infraspinatus, subscapularis, and anterior, middle, and posterior bundles of the deltoid). The muscle strength of the unaffected side was compared to the affected side, and muscle imbalance indices were calculated. Muscle imbalance indices between male and female patients, dominant and non-dominant sides, and groups A and B were compared. Pearson correlation analysis was used to examine the relationship between muscle imbalance indices and CSA as well as VAS scores. Muscle strength in all muscle groups on the affected side was significantly lower than on the unaffected side ( P<0.05). The muscle imbalance indices for the supraspinatus, subscapularis, infraspinatus, and anterior, middle, and posterior bundles of the deltoid were 14.8%±24.4%, 5.9%±9.7%, 7.2% (0, 9.1%), 17.2% (5.9%, 26.9%), 8.3%±21.3%, and 10.2% (2.8%, 15.4%), respectively. The muscle imbalance indices of the anterior bundle of the deltoid, supraspinatus, and infraspinatus were significantly lower in male patients compared to female patients ( P<0.05); however, there was no significant difference in muscle imbalance indices among other muscle groups between male and female patients or between the dominant and non-dominant sides ( P>0.05). There was a positive correlation between the muscle imbalance indices of infraspinatus and VAS score ( P<0.05), and a positive correlation between CSA and the muscle imbalance indices of middle bundle of deltoid ( P<0.05). There was no correlation between the muscle imbalance indices of other muscle groups and VAS score or CSA ( P>0.05). Preoperative CSA ranged from 17.6° to 39.4°, with a mean of 31.1°. There were 9 cases in group A and 33 cases in group B. The muscle imbalance indices of the anterior bundle of the deltoid was significantly lower in group A compared to group B ( P<0.05), while there was no significant difference in muscle imbalance indices among other muscle groups between group A and group B ( P>0.05). Patients with RCT have a phenomenon of deltoid muscle strength reduction, which is more pronounced in the population with a larger CSA.

ELSO Interim Guidelines for Venoarterial Extracorporeal Membrane Oxygenation in Adult Cardiac Patients.

ELSO Interim Guidelines for Venoarterial Extracorporeal Membrane Oxygenation in Adult Cardiac Patients.

Single medial approach for the treatment of Schatzker IV tibial plateau fractures

Objective Try to treat the Schatzker Ⅳ tibial plateau fractures with a single medial approach. Methods A single medial longitudinal incision was used to treat 16 cases of Schatzker type Ⅳ tibial plateau fractures admitted to hospital from January 2013 to January 2016 which diagnosed by computed tomography (CT). The range of peeling up to the anterior edge of the tibia, the back side skipping over the posterior bone crest to expose the Posterior surface, persisting the joint capsule and the medial collateral ligament, and the far end reached 3-5 cm beyond the fracture line. As the lower limbs in the situation of external rotation with hip and knee flexion, open the medial fracture, using a strutting forceps to brace the bone block, made out he collapsing cartilage and subchondral bone which belong to de back column, Using the detacher to lift the subchondral bone together with the cartilage surface, lift up to the lateral side until it can’t be raised again, fixed them with 2-3 Kirschner-pins of 1.5 mm-diameter. And then used a large C type Matta forceps to clamp the fracture line for recovering the width of tibial platform. A Tomofix plate was used to fix the fracture in the position of posterior bone crest. The intercondylar eminence fracture of the anterior cruciate ligament was fixed under direct vision, and the supporting plate was placed in the posterior medial wall to fix the posterior medial small fracture. The standard X-ray films of bilateral knee joint were taken and compared after the operation. The knee joint activity was measured at 1 year follow-up after 1 years. The healing of subchondral fracture and no secondary collapse were performed by plain scan, and the function of the knee joint was evaluated by Lysholm scoring system. Results 15 cases were followed up for more than 1 years. All the X-ray showed fracture healing at half a year. CT confirmed that the fracture healed completely at the time of reexamination. The condylar crest avulsion fracture healed well, there was no secondary cartilage surface collapse, no obvious osteoarthritis, the average knee joint activity was 118°, and the average of Lysholm score was 87. Conclusion Combined approach is an effective method for the treatment of complex tibial plateau fractures, but for Schatzker Ⅳ fractures, a good reduction can be achieved with a single medial approach combined with some proper tools. Key words: Tibial plateau fractures; Medial approach; Schatzker Ⅳ

Correlation between the coverage percentage of prosthesis and postoperative hidden blood loss in primary total knee arthroplasty

Background The aim of this study was to determine the relationship between prosthesis coverage and postoperative hidden blood loss (HBL) in primary total knee arthroplasty (TKA). Methods A total of 120 patients who had undergone unilateral TKA from August 2012 to May 2013 were retrospectively studied. The Gross formula was used to calculate the amount of HBL. Routine standard anteroposterior (AP) and lateral X-ray films of the knee joint were taken postoperatively and used to measure the percentages of coronal femoral and of coronal and sagittal tibial prosthetic coverage. Then Pearson's correlation analysis was performed to assess the correlations between the percentages of prosthetic coverage for each AP and lateral position and HBL on the first and third postoperative days. Results The volumes of HBL on the first and third postoperative days after TKA were (786.5±191.6) ml and (1 256.6±205.1) ml, respectively, and lateral X-ray film measurements of percentages of coronal femoral, tibial coronal, and sagittal prosthetic coverage were (87.9±2.5)%, (88.5±2.2)%, and (89.1±2.3)%, respectively. Pearson's correlation analysis showed statistically significant correlations between percentages of total knee prosthetic coverage for each AP and lateral position and volumes of HBL on the first and third postoperative days (P &lt;0.05). Conclusions HBL after TKA correlates with degree of prosthetic coverage. To some extent, the size of the surfaces exposed by osteotomy determines the amount of HBL. Choice of the appropriate prosthesis can significantly reduce postoperative HBL. Designing individualized prostheses would be a worthwhile development in joint replacement surgery.

Pelvic retroversion is the key protective mechanism of L4-5 degenerative spondylolisthesis.

To explore the role of spinopelvic sagittal alignment in the pathological mechanism of degenerative spondlylolisthesis (DS) development. A total of 52 asymptomatic volunteers, 32 single segment L4-5 DS and 29 lumbar spinal stenosis (LSS) without spondylolisthesis patients were enrolled. All subjects had standard lumbar spine X-ray films with standard position along with lumbar spine magnetic resonance image. Comparative analysis of sagittal parameters and disc degeneration grades among asymptomatic volunteers and patients with the two disorders were performed. Compared to normal population (NP) and LSS, DS showed significantly greater pelvic incidence (PI), sacral slope (SS) and lumbar lordosis (LL), while LSS showed significantly smaller PT and PT/SS. DS showed significantly greater L5 slope than NP and LSS. In both Great-PI group and Small-PI group, all above differences between DS and LSS remained. LSS showed significantly higher degenerative grade of each adjacent disc than DS. Population with adjacent segment degeneration showed higher incidence of pelvic retroversion (PT/SS ≥1), and LSS showed greater proportion of adjacent segment degeneration than DS. Lumbar spine morphology of great LL determined by great PI is a risk factor of L4-5 DS. L5 slope is a parameter that can be used to predict the risk of L4-5 DS. Pelvic retroversion is the key protective mechanism from DS. Adjacent segment degeneration is a driving factor of pelvic retroversion for compensation of lumbar sagittal malalignment.

Comparación de los estadíos de maduración de la falange media del tercer dedo de la mano derecha e izquierda en pacientes de 8 a 15 años de edad

El objetivo de la investigación fue determinar las diferencias entre los estadíos de maduración ósea de la falange media del tercer dedo (MP3) de la mano derecha e izquierda. Trabajamos con la hipótesis de que sí existen diferencias significativas entre los estadíos de maduración MP3 de ambas manos. Materiales y métodos: La población estuvo conformada por niños de 8 a 15 años de la Facultad de Odontología de la UNMSM. Se extrajo una muestra de 84 individuos. Se colocó una placa radiográfica convencional por debajo de MP3 y se tomó la radiografía con un equipo de rayos X convencional. Esto se hizo tanto en la mano derecha como en la izquierda. Los resultados mostraron que la distribución de todos los estadíos fue la misma en ambas manos, a excepción de los estadíos H e I, en donde el estadío H de la mano izquierda tuvo tres pacientes menos en relación con la derecha. Al aplicar la prueba de chi cuadrado (95%), hallamos que ambas manos estuvieron altamente correlacionadas (p &amp;lt; 0.005), por lo tanto se puede afirmar que las diferencias no fueron significativas. Concluimos que la toma radiográfica de MP3, según el método utilizado, puede realizarse en ambas manos, ya que las diferencias no son clínica ni estadísticamente significativas.

An analysis of 45 patients with pure nasal fractures

Nasal fracture is generally encountered alone or in combination with other serious injuries. The objective of this study was to analyze patients who had pure nasal fracture. Forty-five records from patients with pure nasal fracture treated in the hospital between 7 October 2005 and 14 December 2011 were included. The following nasal fracture criteria were evaluated: age at the time of nasal trauma, gender, accident type, use of alcohol, findings of the physical examination, treatment time after the nasal fracture, and year and seasonal distribution. The age ranged from 6-32 years, with a mean age of 21 years. The most frequent reasons of the injury were violence 60% (27 cases) followed by falling 31% (14 cases), accidents 4.5% (2 cases) and sport injuries 4.5% (2 cases). The most frequent findings were tenderness in 71.1% (32 cases), followed by swelling in 51.1% (23 cases), nasal deviation in 42.2% (19 cases), and epistaxis in 15.6% (7 cases). Nasal bone fracture was diagnosed exactly by standard X-ray films in 91.1% (41 cases). In this study; pure nasal bone fractures occurred primarily among men under 25 years of age, and fights were found to be the main etiologic factor.

Intrusive luxation of tooth due to bite block after oral endotracheal intubation

Intrusive luxation of tooth due to bite block after oral endotracheal intubation

A systematic review of the clinical effectiveness of EOS 2D/3D X-ray imaging system

To evaluate the available evidence for the clinical effectiveness of the EOS(®) 2D/3D X-ray imaging system for the evaluation and monitoring of scoliosis and other relevant orthopaedic conditions. A systematic review of studies of EOS(®), compared with standard X-ray film, computed radiography or digital radiography, of patients with orthopaedic conditions was undertaken. Ten electronic databases were searched. The quality of the included studies was assessed and a narrative synthesis undertaken. Three small, limited quality studies, primarily of children with scoliosis, were identified. No patient health outcomes were reported. Spinal image quality was comparable or better overall with EOS(®). Radiation dose was considerably lower with EOS(®) than X-ray film or computed radiography; the mean entrance surface dose was over five times lower with EOS(®) for the posteroanterior spine radiograph and over six times lower for the lateral spine radiograph. The available clinical evidence for EOS(®) is limited to establishing its basic technical ability. The technical advancements associated with EOS(®) (the ability to generate a full body scan and to construct a three-dimensional model from synchronously acquired lateral and posteroanterior images) have not been evaluated in terms of their ability to improve patient outcomes. Whilst radiation dose is a concern for orthopaedic patients who require repeated imaging, it is difficult to quantify the reductions in radiation dose seen with EOS(®) in terms of patient health benefits. Clinical studies that investigate the impact of EOS(®) on patient management are required.

Cortical Osteoid Osteomas of the Calcaneus Managed by En Bloc Resection and Autogenous Iliac Bone Grafting

Osteoid osteoma was firstly described by Bergstrand [1] as a benign osteoblastic tumor in 1930, then followed by Jaffe [2] in 1935 who described it and he was the first one to recognize it as a unique entity. The most common sites of osteoid osteomas are the femur, especially the intertrochanteric or intracapsular regions of the hip, which are affected in two thirds of cases [2,3] the other common sites are the diaphyseal parts of the tibia and the humerus. This osteoid osteoma is not common in the foot and its incidence ranges from 4% to 16%, the preferred locations in the foot are the talus which ranges from 31% to 59% followed by the calcaneus which ranges from 12.5% to 22% of all osteoid osteomas of the foot [3-5]. There are frequent difficulties in the diagnosis and the localization of osteoid osteomas in the foot and also difficulties for the standard x-ray films to detect the tumor especially if there are extensive sclerosis in cortical lesion or arthrititic changes in subarticular regions in the small tarsal bone [3-6]. In this study we evaluated the results of six rare cases of cortical osteoid osteomas of the calcaneus managed by en bloc resection of osteoid osteomas with autogenous iliac bone grafting.

Digitalização de filmes radiográficos com costura de imagens

OBJETIVO: Propor um método reprodutível, de fácil utilização e de baixo custo para a digitalização de filmes radiográficos de todos os tamanhos padrões, concentrando nossos esforços em filmes radiográficos de tórax. MATERIAIS E MÉTODOS: O objetivo de baixo custo ditou o uso de um escâner A4 com adaptador de transparência, bem como um software de costura de imagens otimizado, que tira proveito da geometria do escâner e área de captura constante, bem como o conhecimento das dimensões dos filmes radiográficos padrões. RESULTADOS: O resultado final do método proposto é uma imagem de alta resolução com bom contraste e sem artefatos de costura perceptíveis. CONCLUSÃO: O método de digitalização proposto usando um escâner A4 possibilita reprodutibilidade, excelente qualidade de imagem e alto grau de certeza na identificação de lesões.

Treatment of lower extremity long bone nonunion with expandable intramedullary nailing and autologous bone grafting

Nonunion of long bones in lower limbs is a common complication of orthopedic trauma that can be extremely debilitating. This retrospective study describes our experience using expandable intramedullary nails and autologous bone grafting in treating lower limb long bone nonunion with bone defects. Nineteen patients (mean age 38.9 years, range 18-61) with lower limb long bone nonunion and defects caused by femoral or tibial fracture types were as follows: A2 (3 femoral, 1 tibial), A3 (1 femoral, 2 tibial), B2 (3 femoral, 4 tibial), and B3 (1 femoral, 4 tibial). Expandable intramedullary nailing and autologous bone (iliac and/or fibular) grafting were used for the treatment. Postoperative bone healing as determined by analysis of standard anteroposterior and lateral X-ray films every 4 weeks. Complications were noted. The average number of previous surgeries was 1.9 (range 1-4). The mean duration from original injury to treatment was 17.6 months (range 9-40 months). Femoral shaft nonunion healed on average of 26.5 weeks (range 16-60 weeks) after surgery, while tibial shaft nonunion healed on average of 23.6 weeks (range 12-40 weeks) after surgery. Class I healing occurred in all but two patients who experienced chronic postoperative osteomyelitis and delayed wound healing, respectively. Two patients complained of postoperative donor site pain. The use of expandable intramedullary nails and autologous bone grafts was an effective method for repair of nonunion of lower limb fractures combining with bone defects with minimal complications.

Measurements of parameters of posteroanterior X-ray films of distal radial fracture and their significance

To provide the basic knowledge of wrist joint for diagnosing of these morphological change in pathological condition by measuring the posteroanterior X-ray films of different types of distal radius fracture by AO classification. Eleven radiographic indexes were measured including following 7 new parameters of 83 cases of distal radius fracture: ulnar styloid length (USL), ulnar head length (UHL), ulnar head diameter (UHD), maximal distal radius width (MDRW), proximal distal radius width (PDRW), sigmoid notch length (SNL) and sigmoid notch width (SNW) by Pacs system in standard X-ray films. The indexes were defined by the ratio of these parameters to the length of the third metacarpal. Statistical significance of indexes and correlations of parameters were analyzed by SPSS 16.0. It was found that indexes of 11 parameters and 27 pairs of indexes had significantly different. Compared the indexes of 14 groups with normal group existed statistical significance, 62 pairs value of 11 parameters had correlations. The study provides additional radiographic index that will be helpful to more careful diagnosis and treatment of the distal radius fractures and their associated injuries such as ulnar wrist injuries or carpal instability.

Grundlagen der Flachdetektor-CT (FD-CT)

Flat detectors (FDs) have been developed for use in radiography and fluoroscopy to replace standard X-ray film, film-screen combinations and image intensifiers (II). In comparison to X-ray film and II, FD technology offers higher dynamic range, dose reduction, fast digital readout and the possibility for dynamic acquisitions of image series, yet keeping to a compact design. It appeared logical to employ FD designs also for computed tomography (CT) imaging. FDCT has meanwhile become widely accepted for interventional and intra-operative imaging using C-arm systems. Additionally, the introduction of FD technology was a milestone for soft-tissue CT imaging in the interventional suite which was not possible with II systems in the past. This review focuses on technical and performance issues of FD technology and its wide range of applications for CT imaging. FDCT is not aimed at challenging standard clinical CT as regards to the typical diagnostic examinations, but it has already proven unique for a number of dedicated CT applications offering distinct practical advantages, above all the availability of immediate CT imaging during an intervention.

Distale Humerusfraktur

Independently of lacerated anatomic structures, the ensuing fracture type, concomitant injuries around the joint, the primary aim in treating distal humeral fractures is the restoration of a painfree, mechanically loadable elbow that has a free range of motion. To achieve these goals the fracture and its associated injuries have to be adequately diagnosed, adequately surgically treated, and after reconstruction must undergo an early physical therapy (PT) protocol. Adequate diagnostics, except for standard X-ray films, include in most cases an additional preoperative CT for evaluation and planning of the surgical approach. Adequate surgical treatment entails anatomic reconstruction and stable fixation via an approach that causes a minimum of additional iatrogenic injury to the adjacent soft tissues. Adequate PT is synonymous with early onset of movement, i.e. as early as the 1st postoperative day if the fixation is stable enough. However, a demanding problem is the increasing number of osteoporosis-associated distal humeral fractures in the elderly population with the development of complex fracture types, partly due to poor bone quality, that are not easily addressed and might lead to unsatisfactory results even after applying standardized protocols including anatomically contoured angular stable plates.

Flat-detector computed tomography (FD-CT)

Flat-panel detectors or, synonymously, flat detectors (FDs) have been developed for use in radiography and fluoroscopy with the defined goal to replace standard X-ray film, film-screen combinations and image intensifiers by an advanced sensor system. FD technology in comparison to X-ray film and image intensifiers offers higher dynamic range, dose reduction, fast digital readout and the possibility for dynamic acquisitions of image series, yet keeping to a compact design. It appeared logical to employ FD designs also for computed tomography (CT) imaging. Respective efforts date back a few years only, but FD-CT has meanwhile become widely accepted for interventional and intra-operative imaging using C-arm systems. FD-CT provides a very efficient way of combining two-dimensional (2D) radiographic or fluoroscopic and 3D CT imaging. In addition, FD technology made its way into a number of dedicated CT scanner developments, such as scanners for the maxillo-facial region or for micro-CT applications. This review focuses on technical and performance issues of FD technology and its full range of applications for CT imaging. A comparison with standard clinical CT is of primary interest. It reveals that FD-CT provides higher spatial resolution, but encompasses a number of disadvantages, such as lower dose efficiency, smaller field of view and lower temporal resolution. FD-CT is not aimed at challenging standard clinical CT as regards to the typical diagnostic examinations; but it has already proven unique for a number of dedicated CT applications, offering distinct practical advantages, above all the availability of immediate CT imaging in the interventional suite or the operating room.

Early predictive value of supine and upright X-ray films of odontoid fractures treated with halo-vest immobilization

Background Although halo-vest immobilization remains a common form of treatment for type II odontoid fractures, nonunion and C1–2 instability may be the result in up to 20% to 40% of patients. Purpose Supine and upright lateral X-ray films may allow early identification of patients likely to fail halo-vest treatment and earlier surgical treatment with decreased morbidity from prolonged unsuccessful halo-vest immobilization. Study design/setting A prospective cohort study was performed. Patient sample Twenty patients with type II odontoid fractures. Outcome measures Posttreatment nonunion and C1–2 instability as determined by plain X-ray films and computed tomography scan. Methods Both supine and upright lateral X-ray films were obtained immediately after halo-vest application and at the 2-week, 6-week, and 3-month follow-up. Flexion-extension lateral X-ray films were obtained after halo-vest removal. Patients with nonunion or instability underwent computed tomography scan. Upright X-ray films were compared serially to identify loss of reduction. Pairs of supine and upright X-ray films were compared to measure any change in displacement or angulation upon transition from supine to upright position. Nonunion patients were compared with healed patients to determine any difference in fracture behavior based on serial supine and upright X-ray films. Results Twenty patients with type II odontoid fractures were identified during the study period. Three patients with multiple trauma underwent immediate surgical stabilization. Three elderly patients with nondisplaced fractures were treated in a cervical orthosis. Fourteen patients initiated and completed 3 months of halo-vest immobilization. After halo-vest removal, 4 of 14 patients (29%) showed radiographic nonunion or instability. In all 4 nonunion patients, supine and upright radiographs at 2 weeks revealed change in fracture angulation ≥5° between the supine and upright positions. In three of these patients standard serial upright lateral X-ray films failed to identify any loss of reduction. In the remaining patient, progressive angulation of 15° was observed. No measurable change in angulation between supine and upright X-ray films was observed in any patient who healed successfully with halo-vest treatment. Conclusions Obtaining both supine and upright lateral X-ray films during the follow-up period may identify patients at risk for failure of halo-vest treatment as early as 2 weeks after initiation of treatment. A change in fracture angulation ≥5° suggests an increased risk of treatment failure and the potential benefit of early surgical stabilization.

Collagen type 1 (COL1A1) Sp1 binding site polymorphism is associated with osteoporotic fractures but not with bone density in post-menopausal women from the Canary Islands: a preliminary study

An association between the polymorphism for transcription factor Sp1 in the gene COL1A1 and low bone density (BMD) and osteoporotic fractures has been described but not confirmed for all races and ages. The aim of this preliminary work was to ascertain whether this association is present in women from the Canary Islands. Polymerase chain reaction RFLP was used to determine COL1A1 polymorphism Sp1 in 199 consecutive outpatient post-menopausal Caucasian women from the Canary Islands, aged 50-70 years. BMD was measured at lumbar spine and hip by DXA and at third lumbar vertebrae by QCT. Prevalent vertebral fractures were recorded on standard lateral X-ray film. Non-vertebral osteoporotic fractures were registered by medical record and self-reported history. Biochemical markers (serum osteocalcin, tartrate-resistant acid phosphatase), blood calcium and phosphate were also assessed. Distribution genotypes were 113 (50.8%) GG homozygotes, 73 (36.7%) Ss heterozygotes and 7 (3.5%) TT homozygotes. All patients with osteoporotic fractures carried the GG allele more frequently than TT homozygotic women. The odds ratio was 3.01 (95% CI 1.6-5.7) for prevalent vertebral fractures (n=62) and 2.33 (95% CI 1.2-4.4) for all osteoporotic fractures (n=65) for the T-carrying allele vs TT homozygotic women. There was no difference in BMD measured by DXA or QCT, nor in bone markers, blood calcium or phosphate. This preliminary study confirmed that the presence of at least one copy of the T allele is associated with osteoporotic fractures, but not with low BMD, in women from the Canary Islands.

Intraoperative Digital Specimen Mammography: Rapid, Accurate Results Expedite Surgery

Specimen mammography during image guided breast surgery is a daily occurrence. The process of specimen travel, imaging and reporting may take 20-30 minutes. An intraoperative method to obtain digital specimen mammograms may expedite the process. We compared intraoperative digital specimen mammography (IDSM) as well as standard specimen mammography (SSM) on 121 consecutive image guided lumpectomies. Each lumpectomy specimen had IDSM obtained followed by travel to radiology for SSM. Surgical decisions were based on all imaging obtained. Data included 1) the ability of each imaging method to identify the target lesion, 2) degree of concordance of surgical interpretation of IDSM compared to radiologist interpretation of SSM, 3) the time required from lumpectomy to surgical review of images from each method, and 4) potential operative time savings. Intraoperative digital specimen mammography (IDSM) was equally as accurate as standard x-ray film specimen mammography. There was no significant difference between 1) the frequency of identification of the target lesion by surgeon or radiologist, 2) lack of identification of any lesion, or 3) frequency of involved margins using imaging criteria. However, there was a marked difference in 1) the time needed to obtain images ready to read, 2) the ability to re-excise tissue promptly, and 3) the overall operating room time with an average decrease of 19 minutes. Intraoperative digital specimen mammography (IDSM) was equally accurate as SSM obtained in this study. Use of this new technology allows surgeons to quickly view specimen images which translate into shorter more efficient operations.

Reversible Oxidation of ERK-directed Protein Phosphatases Drives Oxidative Toxicity in Neurons

Oxidative stress links diverse neuropathological conditions that include stroke, Parkinson's disease, and Alzheimer's disease and has been modeled in vitro with various paradigms that lead to neuronal cell death following the increased accumulation of reactive oxygen species. For example, immortalized neurons and immature primary cortical neurons undergo cell death in response to depletion of the antioxidant glutathione, which can be elicited by administration of glutamate at high concentrations. We have demonstrated previously that this glutamate-induced oxidative toxicity requires activation of the mitogen-activated protein kinase member ERK1/2, but the mechanisms by which this activation takes place in oxidatively stressed neurons are still not fully known. In this study, we demonstrate that during oxidative stress, ERK-directed phosphatases of both the serine/threonine- and tyrosine-directed classes are selectively and reversibly inhibited via a mechanism that is dependent upon the oxidation of cysteine thiols. Furthermore, the impact of ERK-directed phosphatases on ERK1/2 activation and oxidative toxicity in neurons was tested in a neuronal cell line and in primary cortical cultures. Overexpression of the highly ERK-specific phosphatase MKP3 and its catalytic mutant, MKP3 C293S, were neuroprotective in transiently transfected HT22 cells and primary neurons. The neuroprotective effect of the MKP3 C293S mutant, which enhances ERK1/2 phosphorylation but blocks its nuclear translocation, demonstrates the necessity for active ERK1/2 nuclear localization for oxidative toxicity in neurons. Together, these data implicate the inhibition of endogenous ERK-directed phosphatases as a mechanism that leads to aberrant ERK1/2 activation and nuclear accumulation during oxidative toxicity in neurons.