Diastereoselective and Scalable Synthesis of 6-(S)-Hydroxycannabidivarin.

The synthesis of 6-(S)-hydroxycannabidivarin was required to assess its biological activity in the treatment of neurological disorders. A novel and scalable synthesis has been developed where the key step involves a Friedel-Crafts alkylation of phloroglucinol with (1S,2R,5R)-2-hydroxy-2-methyl-5-(prop-1-en-2-yl)cyclohex-3-en-1-ylbenzoate. Careful optimization of the reaction conditions identified trifluoromethanesulfonic acid in isopropyl acetate as the best catalyst/solvent combination, providing optimum regioselectivity, diastereoselectivity, and yield for this step. This enabled the multigram synthesis of 6-(S)-hydroxycannabidivarin in 10 steps from S-(+)-carvone.

Overutilization of Helicopter Emergency Medical Services in Central Gulf Coast Region Results in Unnecessary Expenditure.

INTRODUCTION: When appropriately used, helicopter emergency medical services (HEMSs) allow for timely delivery of severely injured patients to definitive care. Inappropriate utilization of HEMSs results in increased cost to the patient and trauma system. The purpose of this study was to review current HEMS criteria in the central Gulf Coast region and evaluate for potential areas of triage refinement and cost savings. We hypothesized that a significant number of patients received potentially unwarranted HEMS transport. METHODS: A retrospective cohort study of all patients with trauma arriving to a level I trauma center by helicopter over 28 mo was performed; 381 patients with trauma and with HEMS transport from the scene were included. Data were collected from prehospital sources, as well as hospital chart review for each patient. The primary outcome was the rate of unwarranted HEMS transport. RESULTS: A total of 381 adult patients with trauma transported by the HEMS were analyzed, of which 34% were deemed potentially nonwarranted transports. The significant factors correlating with warranted HEMS transport included age, multiple long bone fractures, penetrating mechanism, and vehicle ejection. Insurance demographics did not correlate to transport modality. Many of these patients were transported from a location within the same county or the county adjacent to the trauma center. When comparing patients transported by ground and HEMSs from the same scene, no time savings were identified. Unwarranted transports at the trauma center represented an estimated health care expenditure of over $3 million. CONCLUSIONS: HEMSs may be overused in the central Gulf Coast region, creating the risk for a substantial resource and financial burden to the trauma system. Further collaboration is needed to establish HEMS triage criteria, that is, more appropriate use of resources.

The Prevalence of Metabolic and Endocrine Disturbances on Fracture Nonunion.

OBJECTIVE: This study aims to determine the prevalence of metabolic disturbance in all fracture nonunion cases and identify the most common endocrine abnormalities seen using a simple screening algorithm. METHODS: A retrospective review study was performed evaluating patients who underwent operative intervention for nonunion from January 2010 to December 2018 at 2 level-1 trauma centers. Preoperative laboratory values were recorded for a 9-test "nonunion panel." A metabolic or endocrine abnormality, specifically an abnormality in the thyroid or parathyroid axis, was evaluated. RESULTS: 42% of patients had an undiagnosed metabolic laboratory abnormality. When multiple tests were used, the rate of metabolic dysfunction was between 60% and 75%, depending on the definition of vitamin D insufficiency vs deficiency used. CONCLUSION: Results indicate a relatively high prevalence of metabolic disturbance in patients with nonunion and suggest metabolic screening for all nonunion patients not only those without a mechanical or infectious cause. LEVEL OF EVIDENCE: IV, retrospective case series.

Implementing total-dose ferumoxytol in lieu of split-dose ferumoxytol.

BACKGROUND: Ferumoxytol is Food and Drug Administration-approved as two 510 mg infusions. Retrospective and prospective reviews have established that a single 1020 mg infusion is as efficacious and safe as two 510 mg infusions. OBJECTIVES: To transition our preferred intravenous iron infusion practice from two 510 mg infusions to a single 1020 mg ferumoxytol infusion. PRACTICE DESCRIPTION: This is a prospective process improvement study conducted at Tripler Army Medical Center, a large academic medical center. PRACTICE INNOVATION: We set up an evidence-based project to transition and monitor our preferred iron treatment of ferumoxytol from 2 doses to 1 dose. EVALUATION METHODS: We collected efficacy and safety data for 188 unique patients receiving 228 infusions, of which 62 were single 1020 mg doses, and 166 were two 510 mg doses. RESULTS: Comparing the 1020 mg dose in 62 patients with 166 patients treated with two 510 mg infusions, we found no increase in the rate of infusion reactions (4.8 % vs. 4.8 %) and comparable improvement in ferritin and hemoglobin (144 ng/mL vs. 140 ng/mL; P value = 0.874, and 1.8 g/dL vs. 1.9 g/dL; P value = 0.721, respectively). CONCLUSION: Thus, we were able to successfully transition to total-dose ferumoxytol for iron-deficient anemia, effectively reducing patient treatment visits without any difference in safety or efficacy. Ferumoxytol 1020 mg infused intravenously over 30 minutes in 250 mL normal saline single dose is a viable, safe, and effective treatment for iron-deficiency anemia.

Ancestral Function and Diversification of a Horizontally Acquired Oomycete Carboxylic Acid Transporter.

Horizontal gene transfer (HGT) can equip organisms with novel genes, expanding the repertoire of genetic material available for evolutionary innovation and allowing recipient lineages to colonize new environments. However, few studies have characterized the functions of HGT genes experimentally or examined postacquisition functional divergence. Here, we report the use of ancestral sequence reconstruction and heterologous expression in Saccharomyces cerevisiae to examine the evolutionary history of an oomycete transporter gene family that was horizontally acquired from fungi. We demonstrate that the inferred ancestral oomycete HGT transporter proteins and their extant descendants transport dicarboxylic acids which are intermediates of the tricarboxylic acid cycle. The substrate specificity profile of the most ancestral protein has largely been retained throughout the radiation of oomycetes, including in both plant and animal pathogens and in a free-living saprotroph, indicating that the ancestral HGT transporter function has been maintained by selection across a range of different lifestyles. No evidence of neofunctionalization in terms of substrate specificity was detected for different HGT transporter paralogues which have different patterns of temporal expression. However, a striking expansion of substrate range was observed for one plant pathogenic oomycete, with a HGT derived paralogue from Pythium aphanidermatum encoding a protein that enables tricarboxylic acid uptake in addition to dicarboxylic acid uptake. This demonstrates that HGT acquisitions can provide functional additions to the recipient proteome as well as the foundation material for the evolution of expanded protein functions.

Workers' Compensation: The Burden on Healthcare Resource Utilization After Foot and Ankle Surgery.

INTRODUCTION: The purpose of this study is to investigate the amount of healthcare resources dedicated to patients with WC after common foot or ankle procedures compared with a procedure-matched control group. METHODS: A retrospective review was performed of patients with WC and without WC undergoing foot and ankle procedures. Measures of healthcare burden included clinical communications, documents, prescriptions, office visits, and days to return to work and clinic discharge. RESULTS: Collectively, 142 patients met the inclusion criteria. Patients with workers' compensation had increased office communication encounters (P < 0.001), processed documents (P < 0.001), medication prescriptions (P < 0.001), number of office visits (P < 0.001), number of days until return to work (P < 0.001), and days until final disposition from clinic (P < 0.001). Patients with workers' compensation were more likely to have postoperative complications (OR 2.1; 95% CI, 1.0 to 4.3; P = 0.04), secondary surgeries (OR 8.2; 95% CI, 2.3 to 29.4; P < 0.001), and new complaints during the perioperative period (OR 1.9; 95% CI, 0.9 to 4.0; P = 0.07) but were less likely to cancel appointments (OR 0.41; 95% CI, 0.19 to 0.86; P = 0.02). DISCUSSION: When undergoing common foot and ankle orthopaedic procedures, patients with WC demonstrated increased healthcare utilization of resources. This included more office staff work burden dedicated to patients with WC for longer amounts of time, effectively doubling the effort of a non-WC cohort.

Erector Spinae Plane Blocks for Circumferential Lumbar Spinal Fusion: Retrospective Cohort Study.

BACKGROUND: Circumferential lumbar spine fusions are extensive procedures that involve accessing the lumbar spine from multiple approaches. These surgeries often make postoperative pain control challenging, and efforts have been made to find alternative methods of analgesia that do not rely solely on opioids. The use of erector spinae plane (ESP) blocks has been found to be effective in controlling pain while decreasing narcotic requirements in patients undergoing thoracolumbar spine surgery. The purpose of this study is to evaluate the efficacy of ESP blocks for postoperative pain control and its effect on opioid consumption in patients undergoing circumferential lumbar spinal fusion. METHODS: A retrospective review was performed on patients undergoing 1- or 2-level elective anterior lumbar interbody fusion with open posterior decompression and posterolateral fusion. An analysis was performed to determine the effect of ESP blocks on hospital length of stay (LOS), pain scores using the visual analog scale, and opioid consumption using morphine milligram equivalents. RESULTS: 144 patients were included in the cohort analysis, of whom 36 patients received a preoperative ESP block and 108 did not. Demographic data, comorbidities, and number of levels fused were equally distributed between groups. Patients who received an ESP block had shorter LOS (3.0 vs 4.0 days, P = 0.005) and lower cumulative morphine milligram equivalent in the first 48 hours after surgery (123.7 vs 141.2, P = 0.05). Visual analog scale scores did not significantly differ between patients group except for on postoperative day 4 and at 12-month follow-up. CONCLUSIONS: The use of ESP blocks for patients undergoing 1- or 2-level circumferential fusion via an anterior lumbar interbody fusion with concomitant posterior open procedures was associated with decreased postoperative inpatient opioid requirements and LOS. This cohort study supports the growing body of evidence that ESP blocks are a useful adjunct for multimodal pain control. LEVEL OF EVIDENCE: 3 CLINICAL RELEVANCE: The data and results of this study provide clinical evidence supporting the use of ESP blocks in patients undergoing circumferential lumbar spine fusion procedures.

Transcarotid stenting of extracranial carotid artery aneurysm with covered stents and flow reversal.

Introduction: An extracranial carotid artery aneurysm (ECAA) is a rare pathology comprising <1% of all arterial aneurysms. The etiology includes trauma, previous surgery, radiation, and infection. Treatment of ECAAs has evolved from open repair to endovascular repair with stenting. Reports of endovascular repair describe the transfemoral approach; however, little more than case reports are available describing the transcarotid approach for ECAAs. In this study, we describe a cohort of patients who safely underwent transcarotid repair of ECAAs. Methods: We performed a retrospective medical record review of all cases of transcarotid stenting using covered stents for a carotid aneurysm within 11 different hospitals within the Memorial Hermann Health System from December 2019 through December 2022. Technical success is defined as coverage of the aneurysm with no endoleak. We report the patient demographics, clinical presentation, intraoperative metrics, and outcomes. Results: Seven patients underwent transcarotid covered stent placement using flow reversal for neurologic protection. Their average age was 65 years, and four of the seven patients were men. Three patients presented with pain, two with transient ischemic attack, one with stroke, and one with a pulsatile mass. Technical success was 100%. All the patients were treated with transcarotid stenting, and the average aneurysm size was 13 mm. The average operative time was 69 minutes, and the flow reversal time was 9 minutes. No postoperative stroke, myocardial infarction, or death occurred. The average length of hospital stay was 2.7 days. Conclusions: A transcarotid approach for endovascular treatment of ECAAs was safe for this cohort of patients, with no postoperative death, stroke, or myocardial infarction. Also, the technical success was 100%.

Postoperative Infection and Revision Surgery Rates in Foot and Ankle Surgery Without Routine Prescription of Prophylactic Antibiotics.

INTRODUCTION: Surgical site infections (SSIs) are associated with patient morbidity and increased healthcare costs. Limited literature in foot and ankle surgery provides guidance about routine administration of postoperative antibiotic prophylaxis. The purpose of this study was to examine the incidence and revision surgery rates of SSI in outpatient foot and ankle surgeries in patients not receiving oral postoperative antibiotic prophylaxis. METHODS: A retrospective review of all outpatient surgeries (n = 1517) conducted by a single surgeon in a tertiary referral academic center was conducted through electronic medical records. Incidence of SSI, revision surgery rate, and associated risk factors were determined. The median follow-up was 6 months. RESULTS: Postoperative infection occurred in 2.9% (n = 44) of the surgeries conducted, with 0.9% of patients (n = 14) requiring return to the operating room. Thirty patients (2.0%) were diagnosed with simple superficial infections, which resolved with local wound care and oral antibiotics. Diabetes (adjusted odds ratio, 2.09; 95% confidence interval, 1.00 to 4.38; P = 0.049) and increasing age (adjusted odds ratio, 1.02; 95% confidence interval, 1.00 to 1.04; P = 0.016) were significantly associated with postoperative infection. DISCUSSION: This study demonstrated low postoperative infection and revision surgery rates without the routine prescription of prophylactic postoperative antibiotics. Increasing age and diabetes are signficant risk factors for developing a postoperative infection.

Initial experience with a modified "candy-plug" technique for false lumen embolization in chronic type B aortic dissection.

Background: Persistent distal false lumen (FL) perfusion after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD) can lead to aneurysmal degeneration and an increased risk of rupture. We have presented our initial experience using a modified "candy-plug" (CP) technique for FL embolization. Methods: From February 2021 to July 2022, we treated six patients using the modified CP technique. All the patients had undergone prior or simultaneous TEVAR for chronic TBAD with persistent FL perfusion and aneurysm expansion. Bilateral common femoral artery access was obtained, and intravascular ultrasound was used to confirm wire access in the true lumen (TL) and FL. A conformable TAG device (W.L. Gore & Associates, Flagstaff, AZ) was used in four cases and an Excluder aortic cuff (W.L. Gore & Associates) in two cases. The device was modified by placing a constraining "napkin-ring" suture through the middle segment of the device. Femoral sheaths were placed in the TL and FL. A standard TL TEVAR extension was performed at the level of the celiac artery (zone 5). Next, the CP device was advanced and deployed in the FL, distally aligning it with the TL device. An appropriately sized Amplatzer II plug (Abbot Vascular, Santa Clara, CA) was then deployed in the constrained segment of the modified stent graft. Completion angiography was performed to confirm successful FL embolization. Results: Technical success was defined as successful deployment of the CP device in the FL. The technical success rate was 100% (six of six patients). Clinical success was defined as the cessation of aneurysm growth on follow-up computed tomography angiography. No 30-day mortality, myocardial infarction, stroke, spinal cord ischemia, access site complications, or aortic-related reinterventions occurred. Surveillance imaging at a mean follow-up of 10 months confirmed clinical success (stable aneurysm size or shrinkage) for all five patients with follow-up data available. Conclusions: The modified CP embolization technique is a promising solution for persistent distal FL perfusion after TEVAR for TBAD. Further investigation is required to determine the long-term durability of this technique as an adjunct to TEVAR to promote aortic remodeling.

Transversus Abdominis Plane Block as Part of a Multimodal Analgesic Regimen in Patients Undergoing Anterior Lumbar Interbody Fusion: A Retrospective Cohort Study.

BACKGROUND: Opioids are a mainstay for pain control in patients undergoing lumbar spine surgery but are associated with a high risk of dependence and significant adverse effects. Efforts continue to be made to utilize non-narcotic agents such as regional nerve block for pain control as part of a multimodal analgesia regimen. Recently, transversus abdominis plane (TAP) blocks have proven beneficial for patients undergoing lumbar fusion procedures. The purpose of this study is to evaluate the efficacy of TAP blocks for postoperative pain control and the effect on opioid consumption and hospital length of stay (LOS) in patients undergoing anterior lumbar interbody fusion (ALIF). METHODS: A retrospective review of patients undergoing elective ALIF included collection of data on demographics, LOS, pain scores using visual analog scale (VAS), opioid consumption using morphine milligram equivalents (MME) from postoperative day (POD) 0 to 5, and any complications. Patients who underwent primary ALIF or ALIF with concomitant posterolateral lumbar fusion were included. RESULTS: A total of 99 patients met inclusion criteria; 47 had a preoperative TAP block and 52 did not. Demographic data and number of levels fused were equally distributed between the groups. The TAP group had significantly lower MME consumption postoperatively during POD 0 to 2 and 0 to 5. VAS pain scores were lower for TAP block patients on POD 3 and 4; otherwise, there was no significant difference. LOS and complication rates were not significantly different. A multiple regression analysis found male sex to be a predictor of increased postoperative MME, while age and TAP block were significant predictors of decreased MME. CONCLUSIONS: The use of TAP block for patients undergoing ALIF was associated with less cumulative MME consumption in the immediate postoperative period. TAP block may be an effective tool for reducing postoperative opioid consumption in patients undergoing ALIF. CLINICAL RELEVANCE: The data in this study provide clinical relevance supporting the use of TAP blocks for patients undergoing ALIF procedures.

Topical Antibiotic Powder and Nonunion Risk in Surgically Treated Tibial Plateau and Pilon Fractures.

INTRODUCTION: High-energy periarticular tibia fractures are challenging injuries with a significant risk of complications. Postoperative infection rates, although improved, remain unacceptable. Intrawound topical antibiotic (TA) application has been popularized to reduce postoperative infections. Although TA may minimize infections, it remains unclear whether TAs have any impact on the development of nonunion. Recent investigations of TA use in fracture care have questioned its efficacy in vivo and suggested a potentially deleterious effect on fracture healing. This study investigates the impact of TA on nonunion rates in surgically treated high-energy periarticular tibia fractures. METHODS: Retrospective analysis of surgically treated periarticular tibia fractures at a single Level 1 trauma center was conducted. Intervention in question was the clinical effect of intrawound TA powder application at definitive closure. A total of 222 high-energy periarticular tibia fractures were included, 114 with TA use and 108 without. The primary outcome was the occurrence of nonunion, with secondary outcomes being superficial and deep postoperative surgical site infections. RESULTS: Twenty-seven patients (12.1%) were diagnosed with nonunions (14 pilons and 13 plateaus). There was no statistically significant difference in nonunion rates among patients who received topical antibiotics (15.8%) versus the group of patients who did not (8.3%) ( P = 0.23). Odds of developing nonunion was significant for open injuries (odds ratio 6.16, P < 0.001) and patients with a provisional external fixator (odds ratio 8.72, P = 0.03) before definitive fixation. No notable difference in the number of superficial and deep infections was identified between groups. CONCLUSION: The use of TA in high-energy periarticular tibia fractures showed no statistically significant increase in nonunion rates but did not conclusively rule out nonunion as a possible effect of intrawound TA. Additional large-scale multicenter prospective studies are needed to confirm these findings. The current body of literature regarding high-energy periarticular tibia fractures does suggest that TAs lower the risk of postoperative infections, but the nonunion risk remains unclear. LEVEL OF EVIDENCE: Level III, Retrospective Cohort Study.

Noninvasive Expandable Endoprostheses From Reconstruction to Skeletal Maturity: A Surgical Technique and Lengthening Guide.

Limb salvage is the benchmark for pediatric extremity bone sarcomas. However, reconstructive strategies must account for any anticipated remaining growth potential and the resultant limb inequality. Expandable endoprostheses offer the theoretical advantage of immediate weight-bearing, predictable function, and reliable maintenance of leg-length equality. The evolution of the lengthening mechanism now permits noninvasive lengthening, opposed to the multiple open procedures of the past. These design improvements have contributed to their growing popularity. Experience has indicated that these noninvasive implants more reliably achieve leg-length equality, have longer failure-free survival, and decreased complications, although some have noted gearbox and lengthening failures. Currently, no standardize technique exists for managing patients with noninvasive expandable implants from the time of reconstruction to final lengthening at skeletal maturity. This blueprint aims to provide a detailed surgical technique, lengthening schedule, and recommendations for the mitigation and management of complications to achieve successful limb salvage with noninvasive expandable endoprostheses.

Radiographic Outcomes, Union Rates, and Complications Associated With Plantar Implant Positioning for Midfoot Arthrodesis.

BACKGROUND: Midfoot arthrodesis has long been successfully included in the treatment paradigm for a variety of pathologic foot conditions. A concern with midfoot arthrodesis is the rate of nonunion, which historically has been reported between 5% and 10%. Plantar plating has also been noted to be more biomechanically stable when compared to traditional dorsal plating in previous studies. Practical advantages of plantar plating include less dorsal skin irritation and the ability to correct flatfoot deformity from the same medial incision. The purpose of this study is to report the arthrodesis rate, the success of deformity correction, and the complications associated with plantar-based implant placement for arthrodesis of the medial column. METHODS: A retrospective review was undertaken of all consecutive patients between 2012 and 2019 that underwent midfoot arthrodesis with plantar-positioned implants. Radiographic outcomes and complications are reported on 62 patients who underwent midfoot arthrodesis as part of a correction for hallux valgus deformity, flatfoot deformity, degenerative arthritis, Lisfranc injury, or Charcot neuroarthropathy correction. RESULTS: Statistically significant improvement was seen in the lateral talus-first metatarsal angle (Meary angle) and medial arch sag angle for patients treated for flatfoot deformity correction. In patients treated for hallux valgus deformity, there was a reduction in the intermetatarsal angle from 15.4 to 6.8 degrees. The overall nonunion rate was 6.45% in all patients. The rate of nonunion was higher at the NC joint compared to the TMT joint and with compression claw plates. One symptomatic nonunion required revision surgery (1.7%). There were no nonunions when excluding neuroarthropathy patients and smokers. The odds ratio (OR) for nonunion in patients with neuroarthropathy was 6.05 (P < .05), and in active smokers the OR was 2.33 (P < .05). CONCLUSION: Plates placed on the plantar bone surface for midfoot arthrodesis achieved and maintained deformity correction with rare instances of symptomatic hardware for a variety of orthopedic conditions. An overall clinical and radiographic union rate of 94% was achieved. The radiographic union rate improved to 100% when excluding both neuroarthropathy patients and smokers. The incidence of nonunion was higher in smokers, neuroarthropathy patients, naviculocuneiform joint fusions, use of compression claw plates, and when attempting to fuse multiple joints. Incisional healing complications were rarely seen other than in active smokers. LEVEL OF EVIDENCE: Level IV, case series.

Multicenter Research Data of Epilepsy Management in Patients With Sturge-Weber Syndrome.

BACKGROUND: Epilepsy in typical Sturge-Weber syndrome (SWS) is common, and many questions remain regarding the treatment outcomes. We analyzed a large multicenter database with focus on neurological drug treatment in different demographic and SWS characteristic groups. METHODS: A total of 268 patients with brain involvement and a history of seizures were selected from a research data registry generated from a multicenter cross-sectional questionnaire. We examined associations between medication use and binary variables such as sex, ethnicity, and brain, skin, and eye involvement laterality. We analyzed group differences in mean number of antiseizure medications and age at diagnosis, enrollment, and seizure onset and examined differences in median SWS neurological scores in groups of interest. RESULTS: The most frequently used medications were levetiracetam (48.1%), low-dose aspirin (44.8%), oxcarbazepine (39.9%), and phenobarbital (14.9%). Lamotrigine was more frequently used in adults than in children (P = 0.001). History of neurosurgery was associated with no current antiseizure medication use (P = 0.001), whereas bilateral brain involvement and family history of seizures were associated with using a higher number of antiseizure medications (P = 0.002, P = 0.027, respectively). Subjects with bilateral brain involvement and early seizure onset were associated with using a higher number of antiseizure medications (P = 0.002) and phenobarbital use (0.003). CONCLUSIONS: Levetiracetam, low-dose aspirin, and oxcarbazepine were the most frequently used medications. More severely affected patients were frequently on a greater number of antiseizure medications. Surgery for epilepsy was associated with the ability to discontinue antiseizure medication. Longitudinal studies are needed to further investigate medication use in patients with SWS.

Vertical Shear Pelvic Ring Injury Adjacent to Retained Pelvic Hardware: A Case Report.

CASE: A 47-year-old obese woman presented with a vertical shear (VS) pelvic ring injury after a motor vehicle accident around her previous posterior pelvic hardware. The patient underwent closed reduction with percutaneous posterior screw fixation using combined fluoroscopy and O-arm (Medtronic). CONCLUSION: A rare case of VS pelvic injury with indwelling posterior pelvic hardware does not automatically preclude placement of percutaneous sacroiliac and transiliac-transsacral screws. Combining fluoroscopic imaging and O-arm enables safe screw placement, saving patients from invasive surgeries.

Integration of denosumab therapy in the management of giant cell tumors of bone.

A review of the literature indicated denosumab is gaining favorability in the oncology community, particularly with increasing frequency in GCTB. Will denosumab be the breakthrough GCTB treatment? Here, we provide a pertinent case example, a review of the literature regarding the history and basic science behind the use of denosumab for GCTB, highlight the newest insights into the dosing and duration of treatment, and note advancements in the field.

Cerebellar Parieto-occipital Posterior Reversible Encephalopathy Syndrome and Cerebral Metamorphopsia Associated with Asymptomatic Atrial Septum Vegetation and Renal Disease: Case Report.

BACKGROUND Posterior reversible encephalopathy syndrome (PRES) is a poorly characterized and enigmatic syndrome. Despite consistently presenting with nervous system vasogenic edema, this malady has been associated with variable triggers, neurological symptoms, and natural history. CASE REPORT The report presents a 25-year old African American female who presented with altered mental status and bilateral cortical blindness. Neuroimaging identified vasogenic edema in the cerebellum, parietal lobe, and occipital lobe. Her PRES was associated with a hypertensive emergency, renal failure, and an atrial septum vegetation (culture-negative endocarditis). All 3 contributing etiologies were addressed, upon which the patient began to recover. During recovery, the patient experienced cerebral metamorphopsia, visualizing her entire environment in the form of a cartoon. After 2 weeks of treatment she recovered to baseline state of heath, with vasogenic edema resolved on follow-up neuroimaging. CONCLUSIONS This case presents a rarely catalogued phenomena during PRES recovery, cerebral metamorphopsia, along with a new potential association (culture negative atrial septum endocarditis). The report also highlights how PRES recovery patients (with cortical blindness) should be explicitly assessed for cerebral metamorphopsia and Charles Bonnet syndrome - which may distress patients. Lastly, the atypical presentation of cerebellar vasogenic edema in our patient validates existing literature that PRES does not have a uniform picture and is not well served by its current name or proposed diagnostic criteria. Therefore, renaming the disorder to reversible vasogenic edema syndrome and derestricting the diagnostic criteria, may prevent clinicians from being discouraged when faced with diagnosing PRES in the face of atypical findings.

Are there enormous age-trends in stable carbon isotope ratios of oak tree rings?

We test a recent prediction that stable carbon isotope ratios from UK oaks will display age-trends of more than 4‰ per century by measuring >5400 carbon isotope ratios from the late-wood alpha-cellulose of individual rings from 18 modern oak trees and 50 building timbers spanning the 9th-21st centuries. After a very short (c.5 years) juvenile phase with slightly elevated values, the number of series that show rising and falling trends is almost equal (33:35) and the average trend is almost zero. These results are based upon measuring and averaging the trends in individual time-series; the 'mean of the slopes' approach. We demonstrate that the more conventional 'slope of the mean' approach can produce strong but spurious 'age-trends' even when the constituent series are flat, with zero slope and zero variance. We conclude that it is safe to compile stable carbon isotope chronologies from UK oaks without de-trending. The isotope chronologies produced in this way are not subject to the 'segment length curse', which applies to growth measurements, such as ring width or density, and have the potential to retain very long-term climate signals.