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Background: Decompressive hemicraniectomy (DHC) can be a life-saving treatment for patients with severe traumatic brain injury (TBI) with a focal mass lesion who develop refractory elevated intracranial pressure (ICP). Nonetheless, successful completion of this procedure requires maintaining hemodynamic and respiratory stability. Extracorporeal membrane oxygenation (ECMO) use in patients with respiratory or cardiac failure is well described in the literature and has become routinely used in patients with refractory hypoxia unresponsive to traditional mechanical ventilation strategies, but few cases of its use have been reported in the neurosurgical literature., Observations: Herein, the authors describe a unique case in which a man presented after an unwitnessed fall that caused severe TBI without a focal mass lesion. The patient subsequently developed medically refractory elevated ICP secondary to traumatic cerebral edema. He required DHC, but the procedure could only be completed safely with the utilization of intraoperative ECMO., Lessons: As more is learned about the techniques and pitfalls of ECMO, its indications are rapidly expanding. The case presented describes the safe use of ECMO during a major neurosurgical procedure, showing that the technique can be completed safely and offering a therapeutic option for effectively addressing refractory hypoxia and hypercarbia in patients with severe TBI who require urgent or emergency neurosurgical procedures. https://thejns.org/doi/10.3171/CASE24264.

Objectives: To estimate age-specific, sex-specific, and race-specific incidence of posterior reversible encephalopathy syndrome (PRES) in the United States., Methods: We conducted a retrospective cohort study using the State Inpatient Database of Florida (2016-2019), Maryland (2016-2019), and New York (2016-2018). All new cases of PRES in adults (18 years or older) were combined with Census data to compute incidence. We evaluated the generalizability of incident estimates to the entire country using the 2016-2019 National Readmissions Database (NRD)., Results: Across the study period, there were 3,716 incident hospitalizations for PRES in the selected states. The age-standardized and sex-standardized incidence of PRES was 2.7 (95% CI 2.5-2.8) cases/100,000/y. Incidence in female patients was >2 times that of male patients (3.7 vs 1.6 cases/100,000/y, p < 0.001). Incidence increased with age in both sexes ( p -trend <0.001). Similar demographic distribution of first hospitalization for PRES was also noted in the entire country using the NRD. Age-standardized and sex-standardized PRES incidence in Black patients (4.2/100,000/y) was significantly greater than in Non-Hispanic White (2.7/100,000/y) and Hispanic patients (1.2/100,000/y) ( p < 0.001 for pairwise comparisons)., Discussion: The incidence of PRES in the United States is approximately 3/100,000/y, but incidence in female patients is >2 times that of male patients. PRES incidence is higher in Black compared with non-Hispanic White and Hispanic patients., (© 2023 American Academy of Neurology.)

Introduction: Spontaneous spinal epidural hematoma (SSEH) can result from various etiologies with a variable degree of neurological deficits. Here, we describe a rare case of SEH secondary to immune thrombocytopenic purpura (ITP) in a child and review the literature of SSEH caused by ITP., Case Report: A 9-year-old female who presented with rapid neurological decline, including bowel and bladder incontinence and paraparesis. A SSEH was observed extending from C2 to T6, causing a mass effect on the spinal cord. Her platelet count was only 7000/µL. Multidisciplinary care was established with neurosurgery, pediatric hematology, and pediatric surgery. The patient was managed emergently with splenectomy and surgical evacuation, with multilevel laminectomy and laminoplasty for evacuation of the hematoma. After a short course of rehabilitation, the patient regained all neurological function., Conclusion: We report the first case of cervicothoracic SSEH secondary to ITP in a child managed with emergent splenectomy and surgical evacuation with multilevel lamoplasty. We also described the methods of timely diagnosis, urgent management, and overall prognosis of patients with this condition., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: The retroauricular (RA) incision has several theoretical benefits compared with the reverse question mark (RQM) incision for decompressive hemicraniectomy (DHC), but limited data comparing the 2 exist., Methods: Consecutive patients who underwent DHC between 2016 and 2022 and survived ≥30 days at a single institution were included. The primary outcome was wound complication within 30 days (30dWC) requiring reoperation. Secondary outcomes included 90-day wound complication (90dWC), craniectomy size in anterior-posterior (AP) and superior-inferior dimensions, distance from the inferior craniectomy margin to the middle cranial fossa (MCF), estimated blood loss (EBL), and operative duration. Multivariate analyses were performed for each outcome., Results: A total of 110 patients (RA group: 27, RQM group: 83) were included. The incidence of 30dWC was 1.2% and 0 in the RQM and RA groups, respectively. The incidence of 90dWC was 2.4% and 3.7% in the RQM and RA groups, respectively. There was no difference in mean AP size (RQM: 15 cm, RA: 14.4 cm; P = 0.18), superior-inferior size (RQM: 11.8 cm, RA: 11.9 cm; P = 0.92), and distance from MCF (RQM: 15.4 mm, RA: 18 mm; P = 0.18). Mean EBL (RQM: 418 mL, RA: 314 mL; P = 0.36) and operative duration (RQM: 103 min, RA: 89 min; P = 0.14) were similar. There was no difference in cranioplasty wound complications, EBL, or operative duration., Conclusions: Wound complications are comparable between the RQM and RA incisions. The RA incision does not compromise craniectomy size or temporal bone removal., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background and Objective: To test the hypothesis that age-specific, sex-specific, and race-specific and ethnicity-specific incidence of nontraumatic subarachnoid hemorrhage (SAH) increased in the United States over the last decade., Methods: In this retrospective cohort study, validated International Classification of Diseases codes were used to identify all new cases of SAH (n = 39,475) in the State Inpatients Databases of New York and Florida (2007-2017). SAH counts were combined with Census data to calculate incidence. Joinpoint regression was used to compute the annual percentage change (APC) in incidence and to compare trends over time between demographic subgroups., Results: Across the study period, the average annual age-standardized/sex-standardized incidence of SAH in cases per 100,000 population was 11.4, but incidence was significantly higher in women (13.1) compared with that in men (9.6), p < 0.001. Incidence also increased with age in both sexes (men aged 20-44 years: 3.6; men aged 65 years or older: 22.0). Age-standardized and sex-standardized incidence was greater in Black patients (15.4) compared with that in non-Hispanic White (NHW) patients (9.9) and other races and ethnicities, p < 0.001. On joinpoint regression, incidence increased over time (APC 0.7%, p < 0.001), but most of this increase occurred in men aged 45-64 years (APC 1.1%, p = 0.006), men aged 65 years or older (APC 2.3%, p < 0.001), and women aged 65 years or older (APC 0.7%, p = 0.009). Incidence in women aged 20-44 years declined (APC -0.7%, p = 0.017), while those in other age/sex groups remained unchanged over time. Incidence increased in Black patients (APC 1.8%, p = 0.014), whereas that in Asian, Hispanic, and NHW patients did not change significantly over time., Discussion: Nontraumatic SAH incidence in the United States increased over the last decade predominantly in middle-aged men and elderly men and women. Incidence is disproportionately higher and increasing in Black patients, whereas that in other races and ethnicities did not change significantly over time., (© 2022 American Academy of Neurology.)

Epithelioid glioblastoma is a rare tumor in the pediatric population. We present a case report of a 5-year-old boy found to have a large right frontotemporal epithelioid glioblastoma. The patient was treated with maximal safe resection followed by craniospinal radiation. He has now reached 5-year survival and does not have tumor progression. Given the rarity of epithelioid glioblastoma in the pediatric population, the literature surrounding the diagnosis and treatment options for these tumors is reviewed., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objective: Brain tissue oxygen monitoring combined with intracranial pressure (ICP) monitoring in patients with severe traumatic brain injury (sTBI) may confer better outcomes than ICP monitoring alone. The authors sought to investigate this using a national database., Methods: The National Trauma Data Bank from 2013 to 2017 was queried to identify patients with sTBI who had an external ventricular drain or intraparenchymal ICP monitor placed. Patients were stratified according to the placement of an intraparenchymal brain tissue oxygen tension (PbtO2) monitor, and a 2:1 propensity score matching pair was used to compare outcomes in patients with and those without PbtO2 monitoring. Sensitivity analyses were performed using the entire cohort, and each model was adjusted for age, sex, Glasgow Coma Scale score, Injury Severity Score, presence of hypotension, insurance, race, and hospital teaching status. The primary outcome of interest was in-hospital mortality, and secondary outcomes included ICU length of stay (LOS) and overall LOS., Results: A total of 3421 patients with sTBI who underwent ICP monitoring were identified. Of these, 155 (4.5%) patients had a PbtO2 monitor placed. Among the propensity score-matched patients, mortality occurred in 35.4% of patients without oxygen monitoring and 23.4% of patients with oxygen monitoring (OR 0.53, 95% CI 0.33-0.85; p = 0.007). The unfavorable discharge rates were 56.3% and 47.4%, respectively, in patients with and those without oxygen monitoring (OR 1.41, 95% CI 0.87-2.30; p = 0.168). There was no difference in overall LOS, but patients with PbtO2 monitoring had a significantly longer ICU LOS and duration of mechanical ventilation. In the sensitivity analysis, PbtO2 monitoring was associated with decreased odds of mortality (OR 0.56, 95% CI 0.37-0.84) but higher odds of unfavorable discharge (OR 1.59, 95% CI 1.06-2.40)., Conclusions: When combined with ICP monitoring, PbtO2 monitoring was associated with lower inpatient mortality for patients with sTBI. This supports the findings of the recent Brain Oxygen Optimization in Severe Traumatic Brain Injury phase 2 (BOOST 2) trial and highlights the importance of the ongoing BOOST3 trial.

Introduction: The intracerebral hemorrhage (ICH) score provides an estimate of 30-day mortality for patients with intracerebral hemorrhage in order to guide research protocols and clinical decision making. Several variations of such scoring systems have attempted to optimize its prognostic value. More recently, minimally invasive surgical techniques are increasingly being used with promising results. As more patients become candidates for surgical intervention, there is a need to re-discuss the best methods for predicting outcomes with or without surgical intervention., Methods: We systematically performed a scoping review with a comprehensive literature search by two independent reviewers using the PubMed and Cochrane databases for articles pertaining to the "intracerebral hemorrhage score." Relevant articles were selected for analysis and discussion of potential modifications to account for increasing surgical indications., Results: A total of 64 articles were reviewed in depth and identified 37 clinical grading scales for prognostication of spontaneous intracerebral hemorrhage. The original ICH score remains the most widely used and validated. Various authors proposed modifications for improved prognostic accuracy, though no single scale showed consistent superiority. Most recently, scales to account for advances in surgical techniques have been developed but lack external validation., Conclusion: We provide the most comprehensive review to date of prognostic grading scales for patients with intracerebral hemorrhage. Current prognostic tools for patients with intracerebral hemorrhage remain limited and may overestimate risk of a poor outcome. As minimally invasive surgical techniques are developed, prognostic scales should account for surgical candidacy and outcomes.

Background: Cortical bone trajectory (CBT) screws are an alternative to traditional pedicle screws (PS) for lumbar fixation. The proposed benefits of CBT screws include decreased approach-related morbidity and greater cortical bone contact to prevent screw pullout. Relatively little data is published on this technique. Here, we compare the midline lumbar fusion (MIDLF) approach for CBT screw placement to transforaminal lumbar interbody fusion (TLIF) for traditional PS placement., Methods: A prospectively maintained institutional database was retrospectively reviewed for all patients undergoing lumbar spinal fusion using CBT screws over the past 5 years. Controls were identified from the same database as patients undergoing lumbar spinal fusion with traditional PS placement and matched based on age, sex, and number of levels fused. Exclusion criteria included prior lumbar instrumentation. The electronic health record was retrospectively reviewed for demographic, perioperative, and postoperative data., Results: A total of 23 patients who underwent CBT screw placement and 35 controls who received traditional PS were included in the study. The median follow-up time was 52.5 months. The CBT screw group had significantly less mean estimated blood loss than the PS group (186 mL versus 414 mL respectively; P  = .008). Both groups experienced significant improvements in preoperative Oswestry Disability Index (ODI) and visual analog scale (VAS) scores for back and leg pain. However, there was no significant difference between the groups in regard to operative time and amount of improvement in VAS pain score or ODI. The CBT group was associated with a significantly shorter mean length of stay (LOS). There were 2 instances of screw pullout in each group., Conclusions: The MIDLF approach with CBT screw placement is associated with less intraoperative blood loss and shorter LOS than traditional PS placement. There is no difference between the 2 techniques in regard to improvement in pain or disability., Competing Interests: Disclosures and COI: The findings of this work have not been presented or published in part or whole previously. This work is not under consideration for publication elsewhere. No funding was received for this work. The authors of this manuscript have no conflicts of interest to disclose.

Chronic subdural hematoma (cSDH) is a common condition that disproportionately affects older patients. Given the greater risks of general anesthesia in this population, interest has turned towards less invasive surgical approaches such as the subdural evacuating port system (SEPS; Medtronic, Inc., Minneapolis, MN). There is a relative dearth of information about the outcomes following this procedure. Here, we present our institution's experience with SEPS and analyze factors associated with the outcomes. Using a prospectively maintained institutional database, we retrospectively identified all patients who presented with cSDH and received first line therapy with SEPS. Pre- and post-operative clinical and radiographic data was obtained from the electronic health record. Outcomes included success or failure, Modified Rankin Scale (mRS) at discharge, length of stay (LOS), and discharge disposition. A total of 126 patients met the inclusion criteria (36 females and 90 males; mean age of 71.6 years). None of the pre-procedural clinical or radiographic variables were associated with the likelihood of a successful outcome. Increasing age was associated with non-routine hospital discharge (p = 0.003), and lower presenting GCS was associated with longer hospital stay (p = 0.005). Greater thickness of the cSDH was associated with a lower likelihood of having a favorable outcome (mRS ≥ 3; p = 0.003). SEPS is an effective first-line therapy for cSDH. Variables previously reported to limit the effectiveness of the technique (presence of septations, mixed density collections) were not associated with treatment failure., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

We present a 69-year-old woman who presented with chronic headaches and was found to have a pituitary mass on MRI, which was biopsied and said to be lymphocytic hypophysitis. The woman was placed on prednisone and followed with routine eye examinations. Two years later, the lesion gradually increased in size and the woman developed a decrease in peripheral vision in the right eye. An MRI showed abutment of the right optic nerve by the mass. A repeat endoscopic transsphenoidal biopsy/resection of the pituitary lesion was performed. Histopathological analysis of the specimen was consistent with diagnosis of xanthomatous hypophysitis (XH). XH is an inflammatory disorder of the pituitary gland characterized by an infiltration of lipid-laden histiocytes, also known as xanthoma cells. The mass was biopsied and a diagnosis of lymphocytic hypophysitis was made. The woman reported improved visual acuity and peripheral vision postoperatively. One year after the second resection, her visual symptoms worsened. Repeat MRI revealed expansion of the residual pituitary tissue. She was referred to the radiation oncology department for external beam radiation therapy and was placed on a maintenance dose of steroids. Since undergoing radiation therapy, her vision has improved slightly and her 3month MRI revealed stable lesion size. This woman illustrates a rare pituitary pathology presented with a literature review of published patients describing xanthomatous hypophysitis. A discussion of the clinical presentation, epidemiology, etiology, diagnosis, histology and treatment is provided., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Introduction: The requirement for nodal analysis currently confounds the oncological propriety of focused purely endoscopic resection for early-stage colon cancer and complicates the evolution of innovative alternatives such as natural orifice transluminal endoscopic surgery (NOTES) and its hybrids. Adjunctive sentinel node biopsy (SNB) deserves consideration as a means of addressing this shortfall., Methods: Data from two prospectively maintained databases established for multicentric studies of SNB in colon cancer that employed similar methodologies were pooled to establish technique potency selectively in T1/T2 disease (both overall and under optimized conditions) and to project potential clinical impact., Results: Of 891 patients with T1-4, M0 intraperitoneal colon cancer, 225 had T1/T2 disease. Sentinel nodes were either not found or were falsely negative in 18 patients with T1/T2 cancers (8%) as compared with 17% (112/646) in those with T3/T4 disease (P = 0.001). Negative predictive value (NPV) in the former exceeded 95%, while sensitivity [including immunohistochemistry (IHC)] was 81%. In the 193 patients with T1/T2 disease recruited from those centers contributing >22 patients, sensitivity was 89% and NPV 97%. Thus, in this cohort, SNB could have correctly prompted localized resection (obviating en bloc mesenteric dissection) in 75% (144) of patients, including 59 with T1 lesions potentially amenable to intraluminal resection alone as their definitive treatment. Forty-four patients (23.4%) would still have conventional resection, leaving three patients (1.6% overall) understaged (11% false-negative rate)., Conclusion: These findings support the further investigation of SNB as oncological augment for localized resective techniques. Specific prospective study should pursue this goal.

Background: Sentinel lymph node (SLN) mapping (M) for staging in colorectal cancer (CRCa) remains controversial and needs to be validated. This study analyzes results of SLNM at a multi-institutional level for CRCa., Methods: Group A patients underwent SLNM with 1 to 3 mL of 1% lymphazurin. First 1 to 4 blue lymph nodes were designated as SLNs and had focused analysis. Group B had standard resection and nodal staging. Patients with a minimum of 2 years of follow-up were analyzed for recurrence., Results: Overall nodal metastasis were 50% for 500 group A patients versus 35% for 368 group B patients. In SLNM patients success, accuracy, sensitivity, and negative predictability values were 98%, 96%, 90%, and 93%, respectively. With a 2-year minimum follow-up, 153 group A patients had 7% recurrences compared with 25% in 162 group B patients., Conclusion: SLNM is highly feasible and accurate for staging CRCa with higher detection of nodal metastasis and lower recurrences.

Purpose: Sentinel lymph node mapping accurately predicts nodal status in > 90 percent of melanoma and breast and colorectal cancers. However, because of anatomic differences, sentinel lymph node mapping of rectal cancers has been considered inaccurate and difficult relative to colon. A prospective study was undertaken to identify differences in sentinel lymph node mapping between patients with colon cancer and those with rectal cancer., Methods: At operation 1 to 3 ml of 1 percent isosulfan blue dye was injected subserosally around colon cancers. The first to fourth blue-staining nodes seen within ten minutes of injection were marked as sentinel lymph nodes. For cancer of the mid-rectum to low rectum, the dye was injected submucosally via rigid scope and spinal needle. The mesorectum was dissected ex vivo to identify blue nodes nearest the tumor as sentinel lymph nodes. Multilevel microsections of sentinel lymph nodes were stained with hematoxylin and eosin and immunostained for cytokeratin, and standard examination of the entire specimen was performed., Results: There were 407 consecutive patients (336 with colon and 71 rectum). The sentinel lymph nodes were identified in 99.1 percent of colon and 91.5 percent of rectal patients (P < 0.0001). Skip metastases were found in 3.6 percent of colon vs. 2.8 percent of rectal patients (P = 0.16). Occult micrometastases were found in 13.4 percent of colon vs. 7.0 percent of rectal patients (P = 0.24). Except for success rates, no other parameters were statistically different between colon and rectum. Lower success in sentinel lymph node identification in rectal cancer may have been related to neoadjuvant chemoradiation received in all six of the patients with sentinel lymph node mapping failures., Conclusion: Despite higher success rates in sentinel lymph node identification for colon patients, sentinel lymph node mapping was highly successful (91.5 percent) in rectal patients. Nodal upstaging, skip metastases, and occult metastases were similar.

The mobile SIREMOBIL Iso-C(3D) C-arm (Siemens, Erlangen, Germany) is the first device permitting intraoperative, three-dimensional representation of bone structures. A high-resolution, isotropic 3D data cube in the isocenter with sides of approximately 12 cm is calculated simultaneously. The SIREMOBIL Iso-C(3D) is linked to the navigation system. This makes it possible to transfer the generated 3D data directly to the linked navigation system without the need for surgeon-dependent registration. In this prospective clinical trial, we evaluated the accuracy of pedicle screw placement using this device. In 61 patients, a total of 302 pedicle screws were placed. Only in five cases (1.7%) were misplacements of > or =2 mm shown in postoperative control CT. The average fluoroscopy time was 1.28+/-0.56 min, and the average operative duration was 103.26+/-23.3 min. There were no postoperative neurological complications in any of the 30 patients. From these data, we conclude that Iso-C(3D) navigation is a very accurate method for the placement of pedicle screws.

Experimental data suggest that lumbar torsion contributes to lumbar disc degenerative changes, such as instability, spondylolisthesis and spinal canal stenosis. However, some basic mechanical characteristics of the lumbar spine under torsional loading have not yet been reported in detail. For example, the function of the facet joints under combined mechanical loads such as torsion with superimposed flexion or extension postures is an area of interest about which little biomechanical data have been reported. In this study, the kinematic response to axial torsion with superimposed axial compression (200 N), compression-flexion (3 and 6 Nm) and compression-extension (3 and 6 Nm) was investigated in 10 cadaveric lumbar functional spinal units. Range of motion (ROM), and helical axes of motion (HAM), were analyzed. There was no difference in ROM between no preload, pure compressive and flexion-compression preload conditions. The ROM was significantly reduced by both extension-compression preload conditions (11% reduction for 3 Nm and 19% reduction for 6 Nm of extension) compared to the pure compressive preload. For no preload, the average HAM position in the transverse plane of the intervertebral disc was near the posteriormost part of the disc and located laterally on the side contralateral to the applied torsional moment. In the transverse plane, the HAM position showed a discrete trend towards the posterior part of the specimens during extension. Kinematic data were visualized using computer animation techniques and CT-based reconstructions of the respective specimens. This information may be used for identifying and characterizing physiologic and pathologic motion and for specifying conservative and surgical treatment concepts and, thus, may find application to identifying indications for spinal fusion or in evaluating the effect of future semi-flexible instrumentation.

A new shoulder prosthesis design for proximal humeral fractures has been developed. The rim of the articular component of this prosthesis has several holes to which the bone-tendon junction of the rotator cuff is fixed, to allow an anatomic reconstruction of the glenohumeral unit. The strength of the tuberosity fixation to this prosthesis is investigated in a cadaveric study. Artificial 4-part fractures were created in 18 human, fresh-frozen, paired shoulder joints with intact rotator cuffs. Two methods of tuberosity fixation were used in a matched-pair fashion. In group I the tuberosities were sutured to the rim of the prosthetic head, and in group II the tuberosities were circumferentially tension band-wired. Strength testing was performed on a material-testing machine, and displacement was recorded with an opto-electronic device. Both fixation methods proved to be equally reliable in the forces exerted during activities of daily living without significant displacement of the fracture fragments.

The term computer aided orthopedic surgery (CAOS) stands for approaches that aim to improve visibility to the surgical field and increase application accuracy by means of so-called navigation systems alone or in combination with smart end-effectors when carrying out surgical actions. These goals achieved by linking the bony anatomy being operated on with a virtual representation, such as an image dataset. This article introduces the basic principles of CAOS. Surgical navigation systems that use modern tracking technology are introduced and classified according to the chosen virtual representation of the surgical object, ie, image-free and image-based (preoperative and intraoperative) technology. Within the latter class in particular, CT-and fluoroscopy-based (2-D and 3-D) systems have successfully made their way into the operating room (OR). Challenges during the development of the underlying enabling technologies are presented and references to orthopedic applications in different anatomical areas are given.

Current conventional surgical and pathological techniques substantially understage colon cancer. This is evidenced by the fact that a significant subset of patients who are stage I and II at the time of colectomy return with distant metastases and ultimately succumb to the disease within the next 5 years. The identification of more nodes within a specimen and the detailed analysis of lymph nodes with advanced pathological techniques such as immunohistochemistry and reverse-transcriptase polymerase chain reaction (RT-PCR) can improve the staging of colon cancer, but are also associated with tremendous financial, time, and labor constraints. Sentinel lymph node (SLN) mapping has provided an avenue of staging colon cancer with high success rates and accuracy rates, while maintaining cost- and time-effectiveness. The ability to reproduce these results is dependent on adherence to the technical details of the procedure, and thereby providing the pathologist with the true SLNs, upon which the advanced pathological studies can be applied. We report our experience of SLN mapping for colon tumors in 209 patients, elaborating on the materials used, technical details, pitfalls, and results of the procedure. Our results show a success rate of 100% (209/209) and an overall accuracy rate for predicting positive or negative metastatic disease of 96.2% (201/209). Nodal metastases were identified in 46.2% (85/184) of patients with invasive disease (stage T1 to T4). The SLN was the exclusive site of metastases in 38.8% (33/85) of these patients, and the nodal disease was detected only as micrometastases in 22.4% (19/85). The skip metastases rate (false negatives) was 9.4% (8/85). SLN mapping is a powerful tool for accurate staging of colon cancer with a high success rate. The upstaging associated with this procedure may reveal disease that might otherwise go undetected by conventional surgical and pathological methods. Those patients who are upstaged can then benefit from adjuvant chemotherapy, which has been shown to improve survival of colon cancer patients with nodal disease by at least 33%.

Epidermal growth factor plays a key role in late fetal lung development and differentiation as well as in regulating surfactant protein A synthesis, which is involved in innate immunity of the lung. Here we show that human cytomegalovirus (HCMV), a known lung pathogen in connatal and postnatal infection of neonates as well as transplant recipients, completely down-regulates EGF receptor (EGF-R) on the surface of human fetal lung fibroblasts. Inhibition of EGF-R synthesis occurs on the transcriptional rather than on the posttranscriptional level. The effect essentially depends on expression of viral immediate early and/or early genes, as binding of ultraviolet light-inactivated virus to the cells had no effect on EGF-R expression. Furthermore, the anti-HCMV drug ganciclovir, which blocks HCMV DNA replication and late gene expression, cannot overcome HCMV-mediated inhibition of EGF-R, suggesting that immediate early or early gene products may be responsible for down-regulation of EGF-R. Interestingly, the glucocorticoid dexamethasone, which is used for its antiinflammatory action to prevent chronic lung disease in preterm infants, promotes HCMV-associated downregulation of the EGF-R by stimulation of viral gene expression. From these data it can be hypothesized that the pathogenesis of HCMV lung infection involves down-regulation of EGF-R and that congenital HCMV infection may cause retardation in lung maturation and surfactant protein synthesis.

To make a direct biomechanical comparison between the sandblasted and acid-etched surface (SLA) and the machined and acid-etched surface (MA), a well-established animal model for implant removal torque testing was employed, using a split-mouth experimental design. All implants had an identical cylindrical solid-screw shape with the standard ITI thread configuration, without any macroscopic retentive structures. After 4, 8, and 12 weeks of bone healing, removal torque testing was performed to evaluate the interfacial shear strength of each surface type. Results showed that the SLA surface was more powerful in enhancing the interfacial shear strength of implants in comparison with the MA surface. Removal torque values of the SLA-surfaced implants were about 30% higher than those of the MA-surfaced implants (p = 0.002) except at 4 weeks, when the difference was at the threshold of statistical significance (p = 0.0519). The mean removal torque values for the SLA implants were 1.5074 Nm at 4 weeks, 1.8022 Nm at 8 weeks, and 1.7130 Nm at 12 weeks; and correspondingly, 1.1924 Nm, 1.3092 Nm, and 1.3226 Nm for the MA implants. It can be concluded that the SLA surface achieves a better bone anchorage than the MA surface, and that sandblasting before acid etching has a beneficial effect on the interfacial shear strength. As regards the bone-implant interfacial stiffness calculated from the torque-rotation curve, the SLA implants showed an overall more than 5% higher stiffness compared with the MA implants, although the difference did not reach the statistical significance level., (Copyright 2002 John Wiley & Sons, Inc. J Biomed Mater Res 60: 325-332, 2002; DOI 10.1002/jbm.10063)

Background: Sentinel lymph node (SLN) mapping for melanoma and breast cancer has greatly enhanced the identification of micrometastases in many patients, thereby upstaging a subset of these patients. The purpose of this study was to see if SLN mapping technique could be used to identify SLNs in colorectal cancer and to assess its impact on pathological staging and treatment., Methods: At the time of surgery, 1 ml of Lymphazurin 1% was injected subserosally around the tumor without injecting into the lumen. The first to fourth blue nodes identified were considered the SLNs, which have the highest probability to contain metastases. A standard oncological resection of the bowel was then performed. Multilevel microsections of the SLNs, including a detailed pathological examination of the entire specimen, was performed., Results: SLN was successfully identified in 85 (98.8%) of 86 patients. In 85 patients, there were 1,367 (16 per patient) lymph nodes examined, of which 140 (1.6 per patient) were identified as SLNs. In 53 (95%) of 56, of whom the SLNs were without metastases (negative), all other non-SLNs also were negative. In 29 (34% of 85) patients, SLNs were positive for metastases; in 14 of the 29 patients, other non-SLNs also were positive in addition to the SLNs. In the other 15 of the 29 patients (18% of 85 patients), SLNs were the only site of metastases, and all other non-SLNs were negative. In 7 patients (8.2% of 85 patients), micrometastases were identified only in 1 or 2 of the 10 sections of a single SLN. In five of seven patients, such micrometastases were detected by hematoxylin and eosin staining and immunohistochemistry; in the other two patients, it was detected only by immunohistochemistry. In patients with negative SLNs, the rate of occurrence of micrometastases in non-SLNs was 5 (0.4%) of 1,184 lymph nodes., Conclusions: SLN mapping can be performed easily in colorectal cancer patients, with an accuracy of more than 95%. The identification of submicroscopic lymph node metastases by this technique may have upstaged these patients (18%) from stage I/II to stage III disease, who may then benefit from further adjuvant chemotherapy.

We describe a new computer algorithm for finding low-energy conformations of proteins. It is a chain-growth method that uses a heuristic bias function to help assemble a hydrophobic core. We call it the Core-directed chain Growth method (CG). We test the CG method on several well-known literature examples of HP lattice model proteins [in which proteins are modeled as sequences of hydrophobic (H) and polar (P) monomers], ranging from 20-64 monomers in two dimensions, and up to 88-mers in three dimensions. Previous nonexhaustive methods--Monte Carlo, a Genetic Algorithm, Hydrophobic Zippers, and Contact Interactions--have been tried on these same model sequences. CG is substantially better at finding the global optima, and avoiding local optima, and it does so in comparable or shorter times. CG finds the global minimum energy of the longest HP lattice model chain for which the global optimum is known, a 3D 88-mer that has only been reachable before by the CHCC complete search method. CG has the potential advantage that it should have nonexponential scaling with chain length. We believe this is a promising method for conformational searching in protein folding algorithms.