Calvarial hemangiomas: Series of 6 cases and review of literature

Calvarial haemangiomas are benign, vascular tumours of the skull involving parietal and frontal bones. Mostly these lesions remain asymptomatic, and present with cosmetic deformity, headache, uncommon neurological symptoms and reported as case reports and case series. The radiological appearance can range from sessile growing intradiploically to globular and the lesions may extend outwards or inwards after eroding the outer and inner tables of the skull. "Sunburst appearance" and "Wagon-wheel sign" are classical radiological findings but the lesions may present simply as a lytic expansile or even sclerotic calvarial mass. Because of varied clinical presentation and atypical radiological characteristics, the final diagnosis can be clinched by histology only. In selected cases where these lesions are not cosmetically acceptable, en bloc resection with tumour free margins followed by cranioplasty is the treatment of choice. Most reports of calvarial haemangiomas in literature are in the form of case reports.

Zinc oxide and ferric oxide nanoparticles combination increase plant growth, yield, and quality of soybean under semiarid region

Zinc (Zn) and iron (Fe) malnutrition are global health challenges that need immediate attention. Hence, to address these issues, a two-pronged approach involving the development and application of novel Zn and Fe products for crop fertilization may be a potential solution. Therefore, zinc oxide (ZnO) (∼13.2 nm) and ferric oxide (Fe2O3) (∼15 nm) nanoparticles (NPs) were synthesized and characterized. Seven nutrients treatments viz, control, ZnO- NPs (25 mg kg-1), Fe2O3-NPs (25 mg kg-1), ZnO + Fe2O3-NPs (25 mg kg-1each), ZnSO4 (55.8 mg kg-1), FeSO4 (60.4 mg kg-1) and ZnSO4+ FeSO4 (55.8 and 60.4 mg kg-1) were arranged in five-time replicated Completely Randomized Design model to test the effectiveness of ZnO and Fe2O3 NPs in two soybean cultivars over conventional zinc sulfate (ZnSO4) and ferrous sulfate (FeSO4) fertilizers. The results indicated that the photosynthetic rate (Pn) and chlorophyll content increased (33.9-86.2%) significantly at the flowering stage with ZnO and Fe2O3 NPs applications, compared to their conventional counterparts. Likewise, the combined application of ZnO and Fe2O3 NPs reduced H2O2 production by 17-19% and increased the superoxide dismutase (SOD) and catalase (CAT) activities by 15-17% and 9.6-11.4% over the combined use of ZnSO4 and FeSO4, respectively. The normalized difference vegetation index (NDVI) showed an increase of 6.9-44.2% under ZnO and Fe2O3 NPs, as well as ZnSO4 and FeSO4. Furthermore, the combined application of NPs enhanced soybean seed yield by 4.6-18.3% compared to conventional Zn and Fe fertilizers. Concerning seed Zn and Fe density, conjoint application of ZnO and Fe2O3 NPs increases Zn by 1.8-2.2-fold and Fe by 19.22-22.58% over the combined application of Zn SO4 and FeSO4, respectively. While the application of NPs significantly decreased seed phytic acid concentrations by 7.3-59.9% compared to the control. These findings suggest that the combined application of ZnO and Fe2O3 NPs effectively enhances soybean productivity, seed nutrient density, and overall produce quality. Therefore, the combined application of ZnO and Fe2O3 -NPs in soybean can be a potential approach for sustainable soybean production and to reduce/arrest Zn and Fe malnutrition in a growing population.

Expert panel recommendations for topical hemostatic agent use in varied bleeding sites and situations during neuro-spine surgeries

Intraoperative bleeding poses a substantial challenge, particularly in neuro-spine surgeries leading to complications such as hematomas, infections, and hemodynamic instability. Despite their proven efficacy, use of topical hemostatic agents (THAs) lacks comprehensive published literature and guidelines particularly in the Indian setting. The present study provides the first-ever Indian expert panel recommendations for effective adjunct THA use in different intraoperative bleeding sites and situations in neuro-spine surgeries. A comprehensive approach, encompassing a literature review, followed by experience sharing in a meeting using a survey helped integrate expert opinions in the form of practical algorithms to guide THA selection. Our survey results revealed a strong inclination towards specific THAs, flowable gelatin + thrombin being choice of THA for difficult to access and problematic bleeding situations during tumor removal/resection, transsphenoidal hypophysectomy and skull-based procedures. Both oxidized regenerated cellulose (ORC)/Fibrillar and flowable gelatin + thrombin were recommended for continuous oozing. ORC/Fibrillar was preferred for arteriovenous and cavernous malformations. This expert-panel guidance on THA use aims to optimize hemostat use practices and improve surgical outcomes in neuro-spine surgery.

Combining biophysical parameters with thermal and RGB indices using machine learning models for predicting yield in yellow rust affected wheat crop

Evaluating crop health and forecasting yields in the early stages are crucial for effective crop and market management during periods of biotic stress for both farmers and policymakers. Field experiments were conducted during 2017-18 and 2018-19 with objective to evaluate the effect of yellow rust on various biophysical parameters of 24 wheat cultivars, with varying levels of resistance to yellow rust and to develop machine learning (ML) models with improved accuracy for predicting yield by integrating thermal and RGB indices with crucial plant biophysical parameters. Results revealed that as the level of rust increased, so did the canopy temperature and there was a significant decrease in crop photosynthesis, transpiration, stomatal conductance, leaf area index, membrane stability index, relative leaf water content, and normalized difference vegetation index due to rust, and the reductions were directly correlated with levels of rust severity. The yield reduction in moderate resistant, low resistant and susceptible cultivars as compared to resistant cultivars, varied from 15.9-16.9%, 28.6-34.4% and 59-61.1%, respectively. The ML models were able to provide relatively accurate early yield estimates, with the accuracy increasing as the harvest approached. The yield prediction performance of the different ML models varied with the stage of the crop growth. Based on the validation output of different ML models, Cubist, PLS, and SpikeSlab models were found to be effective in predicting the wheat yield at an early stage (55-60 days after sowing) of crop growth. The KNN, Cubist, SLR, RF, SpikeSlab, XGB, GPR and PLS models were proved to be more useful in predicting the crop yield at the middle stage (70 days after sowing) of the crop, while RF, SpikeSlab, KNN, Cubist, ELNET, GPR, SLR, XGB and MARS models were found good to predict the crop yield at late stage (80 days after sowing). The study quantified the impact of different levels of rust severity on crop biophysical parameters and demonstrated the usefulness of remote sensing and biophysical parameters data integration using machine-learning models for early yield prediction under biotically stressed conditions.

Aortic root replacement in the setting of a mildly dilated nonsyndromic ascending aorta

OBJECTIVE

There is controversy on how to address mild aortic root dilation during concomitant aortic valve replacement: composite aortic valve conduit replacement or separate ascending aorta and aortic valve replacement. We reviewed our experience to address the issue.

METHODS

We retrospectively reviewed 778 adult nonsyndromic patients with aortic root diameter 55 mm or less who received replacement of the ascending aorta and aortic valve from January 1994 to June 2017. Patients were divided into 2 groups based on the type of aortic root intervention: composite aortic valve conduit replacement in 406 patients (52%) and separate ascending aorta and aortic valve replacement in 372 patients (48%). Propensity matching was used to mitigate differences in baseline patient characteristics and produced 188 matched pairs.

RESULTS

Sinus of Valsalva diameter was 43 mm (39-47). Operative mortality occurred in 3 patients (2%) in the composite aortic valve conduit replacement group and in 5 patients (3%) in the separate ascending aorta and aortic valve replacement group (P = .470). Median follow-up was 9.6 years (8.4-10.1). Long-term mortality was similar in the 2 groups (P = .083). Repeat operation was performed in 13 patients (7%) in the composite aortic valve conduit replacement group and in 19 patients (10%) in the separate ascending aorta and aortic valve replacement group (P = .365). Sinus of Valsalva diameter decreased 2 mm (-4-0; median follow-up 41 months) in the propensity-matched separate ascending aorta and aortic valve replacement group.

CONCLUSIONS

In patients with mild aortic root dilation, separate ascending aorta and aortic valve replacement results in a similar risk of repeat operation and mortality in comparison with composite aortic valve replacement. Separate ascending aorta and aortic valve replacement is not associated with subsequent aortic root dilation on medium-term echocardiography follow-up.

Preoperative Wire Localization: A Simple Guidance Technique for Excision of Deep, Painful, Small, Soft Tissue Neurofibromas

A novel use of preoperative wire localization to aid in the removal of small deep-seated soft tissue nerve sheath tumors is described. Wire localization is commonly used in breast surgery, and applying this technique in neurosurgery will enable the surgeon to directly reach the lesion with smaller incisions and prevent unnecessary soft tissue dissection.

Spinal Subdural Hematoma following Epidural Anesthesia

The spinal subdural space is an avascular, potential space and is a rare location for intraspinal hematomas. Compared to spinal epidural hematomas, spinal subdural hematomas are uncommonly described complications of lumbar puncture for spinal or epidural anesthesia, particularly in patients who have no pre-existing bleeding disorders or history of antiplatelet or anticoagulant intake. We describe a 19-year-old girl who had a large thoracolumbar spinal subdural hematoma following epidural anesthesia for elective cholecystectomy with no pre-existing bleeding diathesis that caused rapidly developing paraplegia that evolved over the next 2 days following surgery. Nine days after the initial surgery she underwent multilevel laminectomy and surgical evacuation with eventual satisfactory recovery. Even epidural anesthesia without thecal sac violation can result in bleeding in the spinal subdural space. The possible sources of bleed in this space may be from injury to an interdural vein or extravasation of subarachnoid bleed into the subdural space. When neurological deficits occur, prompt imaging is mandatory and early evacuation yields gratifying results.

Modifying skin flaps for achieving very large decompressive craniectomies in malignant middle cerebral artery territory infarcts: A technical note

INTRODUCTION

Decompressive craniectomy is a well described treatment to salvage life in large middle cerebral artery (MCA) territory infarcts. The size of the craniectomy is limited by the size of the skin incision and very large craniectomies need large skin flaps that are prone to necrosis at the wound margins.

MATERIAL AND METHODS

We describe two modifications in the skin flap that we have used in 7 patients to achieve very large bony decompressions in malignant MCA infarctions without compromising on flap vascularity. One consists of a linear extension posteriorly from the question mark or reverse question mark incision while the other is an "n" shaped incision.

RESULTS

With these modifications we achieved craniectomies of size 15.6-17.8 cm in the anteroposterior and 10.7-12 cm in vertical axis of the bone flap removed in our patients. There were no additional procedural or wound related complications in a 6-month follow up.

CONCLUSIONS

Removal of a standard size bone flap may achieve suboptimal decompression in cases of large MCA territory infarctions. Imaginative tailoring of skin flaps helps to remove larger volumes of skull with no added procedural morbidity.

Paraspinal Gossypiboma (Textiloma) Mimicking a Soft Tissue Tumor

Paraspinal textilomas are dreaded complications of spinal surgery and rarely reported in view of the medico-legal problems they may create. As many of them are asymptomatic and most are unreported, their true incidence is unknown. They must be kept in mind when re-operating for any mass lesion seen on magnetic resonance imaging in the vicinity of a previously operated spine. We present the case of a 40-year-old man found to have a textiloma as a result of a previous surgery, describe his imaging and histological findings, discuss the causes that might lead to the same, and enumerate preventive strategies to avoid such a complication.

Gingko Leaf Sign: A Classical Imaging Finding in Spinal Meningiomas

The common imaging features surgeons use to distinguish spinal meningiomas from spinal nerve sheath tumors on magnetic resonance (MR) scans include the presence of the “dural tail sign” on contrast-enhanced MR images, hypointensity of the lesion on T2 sequences, presence of calcifications, lack of extraspinal dumbbell extension, and the lack of cystic changes in the lesion. We highlight the rarely described finding–the “Gingko-Leaf” sign that is caused by the stretched denticulate ligament as it extends laterally, through the tumor, from the compressed spinal cord.

Pediatric Epicardial Devices: Early and Midterm Outcomes

BACKGROUND

Lead performance is suboptimal in young patients and a main cause of device system failure. Our objective was to assess early and midterm outcomes after epicardial device implantation in a contemporary pediatric cohort.

METHODS

A total of 116 consecutive pediatric patients underwent 137 epicardial device implantations from 2010 to 2019. Forty pacemakers and 97 implantable cardioverter defibrillators (ICDs) were implanted. Lead failure was defined as leads repaired, replaced, or abandoned due to fracture, dislodgement, or dysfunction. Freedom from device system failure was determined using Kaplan-Meier analysis.

RESULTS

Mean age at implantation was 10 ± 5 years, 46 (34%) were younger than 8 years old, 41 (30%) had prior cardiac surgery, and 38 (28%) had prior devices. Main indications were acquired heart block (17/40 [43%]), sinus node dysfunction (14/40 [35%]), and congenital heart block (7/40 [18%]) for pacemakers, and hypertrophic cardiomyopathy (46/97 [47%]), long QT syndrome (31/97 [32%]), and ventricular arrhythmia (17/97 [18%]) for ICDs. There were no early deaths. Three-year freedom from device system failure was 80% (95% CI 73%, 88%) for all patients and 88% (95% CI 79%, 99%) for patients <8 years old. Device system failure causes included lead fracture (20/34 [59%]), lead dysfunction (5/34 [15%]), lead dislodgement (5/34 [15%]), infection (3/34 [9%]), and pericarditis (1/34 [3%]). Reintervention was required in 26/34 (76%) device system failures.

CONCLUSIONS

Epicardial device implantation is safe, shows acceptable midterm outcomes in children, and is an effective option in patients younger than 8 years old. Close device surveillance continues to be essential to detect lead failure early and ensure timely reintervention.

Contemporary Early Postoperative Cone Repair Outcomes for Patients With Ebstein Anomaly

OBJECTIVE

To describe the early postoperative outcomes after cone repair (CR) for Ebstein anomaly (EA) across the age spectrum.

PATIENTS AND METHODS

For this study, 284 patients from 1 to 73 years of age who underwent CR at Mayo Clinic from June 1, 2007, to December 21, 2018, were separated by age group (1-<4, 4-<19, 19-<40, and 40+ years) and by disease severity for analysis. Outcomes of interest included death, reoperation, readmission, early postoperative complications, cardiac intensive care unit and hospital length of stay, and need for superior cavopulmonary anastomosis.

RESULTS

Mortality within 30 days was 0%. The reoperation rate was 4.9% (n=14) and the median hospital length of stay was 5 days, with no statistical difference between ages at time of CR or severity groups. The readmission rate was 2% (n=6). Postoperative complications were seen in 8.8% (n=25) of cases overall, with higher rates in the youngest age group (21%, P<.001). Superior cavopulmonary anastomosis was most common in the youngest age group (37% vs 17% overall, P<.001) and in those with severe disease (35%, P<.001).

CONCLUSION

Children and adults with Ebstein anomaly have very good early postoperative outcomes with a less than 10% complication and reoperation rate and very low mortality following cone reconstruction. In the setting of good and stable right ventricle function and no symptoms of heart failure or cyanosis, waiting for CR until 4 years of age may minimize early postoperative complications and need for superior cavopulmonary anastomosis.

Complications after Cranioplasty: A Pictorial Narrative with Techniques to Manage and Avoid the Same

Background Cranioplasty following decompressive craniotomy is considered to be a “routine procedure” but several large series have documented a significant amount of both delayed and immediate complications and also a mortality rate of up to 3.6%.

Materials and Methods We went through some of the salient complications (excluding seizures) needing resurgery following interval cranioplasty over the past 18 years at our institution in over 300 cases and analyzed the literature that mention these complications and their treatment.

Results In addition to the commonly mentioned complications, we found some that had been rarely described or not mentioned hitherto in the literature which we have presented as a pictorial narrative. Based on our experience, we recommend some measures that may decrease the incidence or prevent the occurrence of the same.

Conclusions Attention to small but basic surgical techniques will go a long way in preventing unwanted postoperative events.

Dorsal arachnoid web: A rare cause of syringomyelia and myelopathy

Dorsal arachnoidal webs are condensations of arachnoidal tissue densely adherent to the pial surface of the posterior aspect of the dorsal spinal cord. Infrequently described in literature they disrupt the flow of CSF in the spinal subarachnoid space leading to syringomyelia and myelopathy. While there are several theories on their origin, the "scalpel sign" on magnetic resonance imaging is considered to be pathognomonic of this condition. An illustrative case of a 58 year old man with syringomyelia and dorsal cord indentation who presented with spastic paraparesis, gait instability, parasthesias and bilateral non radicular upper limb pain that resolved following excision of the web is described to highlight the importance of considering this diagnosis when cases of so called "idiopathic" syringomyelia are encountered.

Isolated cerebellar infarction in a case of JAK 2 mutation-negative polycythemia vera: A case report

Polycythemia vera is a myeloproliferative disorder caused by clonal expansion of erythroid precursors in the bone marrow commonly due to a mutation in the Janus kinase 2 (JAK2) gene located in the short arm of chromosome 9. Hyperviscosity of blood due to high hematocrit causes a low flow state that may predispose to infarct. These commonly occur in the supratentorial compartment. The case of a 46-year-old man who had an isolated cerebellar infarct with high hematocrit and hemoglobin levels and low serum erythropoietin levels is described. Further investigations eventually led to the unmasking of a JAK2 mutation-negative polycythemia vera.

Applications of Sentinel-2 satellite data for spatio-temporal mapping of deep pools for monitoring the riverine connectivity and assessment of ecological dynamics: a case from Godavari, a tropical river in India (2016-2021)

Rivers are dynamic ecosystems with diverse habitats that require ample connectivity to ensure the flow of ecosystem services, thus empowering the sustainable development of an entire basin. Geo-spatial tools offer powerful prospects for monitoring of aquatic ecosystems. The usefulness of Sentinel-2 datasets to assess river connectivity has been explored for an un-gauged seasonal river system. The present study was undertaken in five ecologically unique river reaches viz. Wainganga, Wardha, Pranhita, Godavari-mid and Manair in Godavari Basin in the Indian Deccan Plateau to map water spread dynamics at various time scales, i.e., fortnightly, monthly, seasonal, annual and demi-decadal during 2016-2021. The maximum value of perennial water spread per square kilometre of total floodplain area (2016-2021), determined using Sentinel-2 imageries, was observed in river Wardha (0.18) followed by Pranhita (0.12) and Wainganga (0.11). The water spread showed a decreasing trend, while the number of patches in the river corridor increased over time from post-monsoon to pre-monsoon season. The copious perennial habitat with relatively larger patches, incessant flow in river Pranhita and obstructed flow, large-sized patches reported in river Wardha during summer months, hold importance in terms of providing refuge to aquatic biota. This study provides evidence for the impact of water projects on spatio-temporal water spread dynamics in Godavari Basin. The demonstrated utility of Sentinel-2 imagery coupled with gauge station measurements for river continuity assessment and deep pool mapping would aid in enhancing our understanding on environmental flow at a spatial scale, which in turn would aid in effective river management to achieve the Sustainable Development Goals. The implications of this study for sustainable environmental management and limitations are also discussed.

Epidural Fluid Collections After Cranioplasty

Background

Common complications following cranioplasty (CP) include infections, seizures, bone flap resorption, and intra-cranial hemorrhages. Epidural fluid collections (EFCs), often seen in the immediate post-operative scan as hypo-dense accumulations below the bone flap, have been very infrequently discussed in the literature as in the majority of the cases, they are small, get resorbed spontaneously, and usually do not cause neurological deficits.

Objective

To document our experience with EFCs that needed re-operation and analyze their clinical and radiological findings.

Materials and Methods

We describe a series of six cases of symptomatic EFCs following CP that necessitated re-operation in a series of 89 cases over 7 years.

Conclusions

EFCs following CP have a different pathogenetic mechanism compared to post-operative epidural hemorrhages. Meticulous surgical techniques can reduce their incidence. Symptomatic EFCs can be evacuated by either re-opening the flap or placing burr holes in the replaced bone. EFCs may become symptomatic even a few days after CP.

Postoperative Salvage Decompressive Craniotomy: Usefulness of The Simple Posteriorly Directed Release Incision in Adequately Expanding Frontotemporal Flaps

Salvage decompressive craniotomies performed following complications after initial planned craniotomies may be inadequate if they are only restricted to removal of the small previously replaced bone flap with some additional nibbling of bone from the surrounding craniotomy margins by retracting the skin. To achieve the aim of adequately decreasing intracranial pressure without affecting wound healing, fresh incisions need to be placed to expand the craniotomy adequately while not compromising vascularity of the scalp. The rationale and safety of the simple posteriorly placed release incision to expand frontotemporal flaps is described.

Flecked Calcifications in Scalp Tumors: Two Cases of Giant Ulcerated Trichilemmal Cysts

In the article, the classical radiological findings in trichilemmal cysts of the scalp are described.

Allergic Contact Dermatitis Due to Cervical Collar

Cervical collars are routinely applied in neurosurgical units following trauma or cervical spine operations. We describe a case of florid allergic contact dermatitis that developed as a complication following collar application in a postoperative patient.

ACTA2-Related Dysgyria: An Under-Recognized Malformation of Cortical Development

BACKGROUND AND PURPOSE

Pathogenic variants in the ACTA2 gene cause a distinctive arterial phenotype that has recently been described to be associated with brain malformation. Our objective was to further characterize gyral abnormalities in patients with ACTA2 pathogenic variants as per the 2020 consensus recommendations for the definition and classification of malformations of cortical development.

MATERIALS AND METHODS

We performed a retrospective, multicentric review of patients with proved ACTA2 pathogenic variants, searching for the presence of malformations of cortical development. A consensus read was performed for all patients, and the type and location of cortical malformation were noted in each. The presence of the typical ACTA2 arterial phenotype as well as demographic and relevant clinical data was obtained.

RESULTS

We included 13 patients with ACTA2 pathogenic variants (Arg179His mutation, n = 11, and Arg179Cys mutation, n = 2). Ninety-two percent (12/13) of patients had peri-Sylvian dysgyria, 77% (10/13) had frontal dysgyria, and 15% (2/13) had generalized dysgyria. The peri-Sylvian location was involved in all patients with dysgyria (12/12). All patients with dysgyria had a characteristic arterial phenotype described in ACTA2 pathogenic variants. One patient did not have dysgyria or the characteristic arterial phenotype.

CONCLUSIONS

Dysgyria is common in patients with ACTA2 pathogenic variants, with a peri-Sylvian and frontal predominance, and was seen in all our patients who also had the typical ACTA2 arterial phenotype.

Interactive effect of elevated tropospheric ozone and carbon dioxide on radiation utilisation, growth and yield of chickpea (Cicer arietinum L.)

An experiment was conducted in the Free Air Ozone and Carbon dioxide Enrichment (FAOCE) facility to study the impact of elevated O₃, CO₂ and their interaction on chickpea crop (cv. Pusa-5023) in terms of phenology, biophysical parameters, yield components, radiation interception and use efficiency. The crop was exposed to elevated O₃ (EO:60ppb), CO₂ (EC:550 ppm) and their combined interactive treatment (ECO: EC+EO) during the entire growing season. Results revealed that the crop's total growth period was shortened by 10, 14 and 17 days under elevated CO₂, elevated O₃ and the combined treatment, respectively. Compared to ambient condition, the leaf area index (LAI) under elevated CO₂ was higher by 4 to 28%, whilst it is reduced by 7.3 to 23.8% under elevated O₃. The yield based radiation use efficiency (RUE_y) was highest under elevated CO₂ (0.48 g MJ^-1), followed by combined (0.41 g MJ^-1), ambient (0.38 g MJ^-1) and elevated O₃ (0.32 g MJ^-1) treatments. Elevated O₃ decreased RUE_y by 15.78% over ambient, and the interaction results in a 7.8% higher RUE_y. The yield was 31.7% more under elevated CO₂ and 21.9% lower in elevated O₃ treatment as compared to the ambient. The combined interactive treatment recorded a higher yield as compared to ambient by 9.7%. Harvest index (HI) was lowest under elevated O₃ (36.10%), followed by ambient (39.18%), combined (40.81%), and highest was under elevated CO₂ (44.18%). Chickpea showed a positive response to elevated CO₂ resulting a 5% increase in HI as compared to ambient condition. Our findings quantified the positive and negative impacts of elevated O₃, CO₂ and their interaction on chickpea and revealed that the negative impacts of elevated O₃ can be compensated by elevated CO₂ in chickpea. This work promotes the understanding of crop behaviour under elevated O₃, CO₂ and their interaction, which can be used as valuable inputs for radiation-based crop simulation models to simulate climate change impact on chickpea crop.

Twin Root Replacement in Congenital Heart Disease: Expert Technique

In adult congenital heart disease, there are situations that require both the aortic and pulmonary roots to be replaced at the time of a reoperation. This commonly involves the replacement of a previously implanted right ventricle-pulmonary artery conduit in a patient with late aortic root dilation and/or neo-aortic valve dysfunction following the Ross procedure. Similar scenarios are encountered in patients having undergone previous repair of conotruncal anomalies such as truncus arteriosus and tetralogy of Fallot with pulmonary atresia. We describe our standardized technique for twin root replacement.

Procurement of lungs from brain-dead donors

Lung transplantation is the procedure of choice in many patients with end-stage lung disease and is being performed more frequently around the world. However, there continues to be shortage of donor organs with the ever-expanding number of recipients on the waiting list, leading to liberalization of the lung donor selection criteria with increasing acceptance of marginal donors while striving for excellent results. This has placed an increasing emphasis on the technique of donor lung procurement and preservation from marginal donors. Good judgment and procurement techniques are necessary to obtain high-quality donor lungs for transplantation and optimize long-term results. This is a review of our current technique used for the procurement of the lungs from brain-dead donors.

An Umbrella Converse for Data Exchange: Applied to Caching, Computing, and Shuffling

The problem of data exchange between multiple nodes with storage and communication capabilities models several current multi-user communication problems like Coded Caching, Data Shuffling, Coded Computing, etc. The goal in such problems is to design communication schemes which accomplish the desired data exchange between the nodes with the optimal (minimum) amount of communication load. In this work, we present a converse to such a general data exchange problem. The expression of the converse depends only on the number of bits to be moved between different subsets of nodes, and does not assume anything further specific about the parameters in the problem. Specific problem formulations, such as those in Coded Caching, Coded Data Shuffling, and Coded Distributed Computing, can be seen as instances of this generic data exchange problem. Applying our generic converse, we can efficiently recover known important converses in these formulations. Further, for a generic coded caching problem with heterogeneous cache sizes at the clients with or without a central server, we obtain a new general converse, which subsumes some existing results. Finally we relate a “centralized” version of our bound to the known generalized independence number bound in index coding and discuss our bound’s tightness in this context.

Sensitivity analysis of cultivar parameters to simulate wheat crop growth and yield under moisture and temperature stress conditions

Sensitivity of cultivar input parameters were characterised on the outputs of yield and growth variables using a web based crop simulation model Web InfoCrop Wheat. The crop model was assessed for each combination of seventeen input cultivar parameters tested under moisture and temperatures stress conditions in four different ecological regions. Three model outputs, total dry matter at harvest, grain yield at harvest and duration of the crop were chosen for subsequent evaluation. The most dominant cultivar parameters were identified to be TPOPT (Optimum Temp), TTVG (Thermal time for germination to 50% Flowering), KDFMAX (Extinction coefficient of leaves at flowering), GNOCF (Slope of storage organ number/m² to dry matter during storage organ formation), POTGWT (Potential storage organ weight) and PHOTOSENS (Photoperiod sensitivity) which were associated with growth, thermal time accumulation, leaf area index, grain number and photosensitivity. Comparison of crop simulations with all the cultivar parameters incorporated from the experimental observations and those with only the most sensitive cultivar parameters incorporated was performed. Outputs of the crop simulation were significantly correlated with results from the field experiments. The present study could save time and effort in generating all the cultivar parameters required to perform the crop simulation under moisture and temperature stress conditions. The most significant cultivar parameters (TPOPT, TTVG, KDFMAX, GNOCF, POTGWT and PHOTOSENS) identified through the sensitivity analysis conducted in this study could significantly simulate the crop growth and yield of wheat.

Twelve-Year Survival After Resection of Hepatocellular Carcinoma with Right Atrial Tumor Thrombus

INTRODUCTION

A large hepatocellular carcinoma (HCC) with macrovascular invasion is generally considered to have poor prognosis due to unfavorable tumor biology andsuch patients are relegated to palliative options. This report describes long term survival after surgery in a patient with HCC and tumor thrombus in the rightatrium.

METHODS

Case records of the patient, details of follow up visits and surveillance computed tomography scans performed were reviewed. A brief discussion of thesurgical strategy adopted along with outcome of similar cases in literature is presented.

RESULTS

A 60 year old man presented with a HCC in segments 4, 5 with extension of tumor into the middle, left hepatic veins, inferior vena cava and right atrium.Patient underwent extraction of the tumor thrombus from the right atrium under cardiopulmonary bypass along with extended left hepatectomy. He receivedthree cycles of adjuvant chemotherapy with Gemcitabine, Oxaliplatin and Interferon. There was a parietal wall recurrence after 1 year and 10 months whichwas excised. Since then he remains well and is on regular follow up for more than 12 years from his index surgery with no evidence of disease, making himthe longest known survivor with such an advanced presentation.

CONCLUSION

This is an unusual instance where aggressive resection for HCC with right atrial tumor thrombus has resulted in an exceptionally long survival.

What Factors Should Be Considered to Improve Outcome of Mechanical Mitral Valve Replacement in Children?

OBJECTIVE

To identify risk factors for pediatric mechanical mitral valve replacement (mMVR) to improve management in this challenging population.

METHODS

From 1993 to 2019, 93 children underwent 119 mMVR operations (median age, 8.8 years [interquartile range [IQR]: 2.1-13.3], 54.6% females) at our institution. Twenty-six (21.8%) patients underwent mMVR at ≤2 years and 93 (78.2%) patients underwent mMVR at >2 years. Median follow-up duration was 7.6 years [IQR: 3.2-12.4].

RESULTS

Early mortality was 9.7%, but decreased with time and was 0% in the most recent era (13.9% from 1993 to 2000, 7.3% from 2001 to 2010, 0% from 2011 to 2019, P = .04). It was higher in patients ≤2 years compared to patients >2 years (26.9% vs 2.2%, P < .01). On multivariable analysis for mitral valve reoperation, valve size <23 mm was significant with a hazard ratio of 5.38 (4.87-19.47, P = .01);. Perioperative stroke occurred in 1% and permanent pacemaker was necessary in 12%. Freedom from mitral valve reoperation was higher in patients >2 years and those with a prosthesis ≥23 mm. Median time to reoperation was 7 years (IQR: 4.5-9.1) in patients >2 years and 3.5 years (IQR: 0.6-7.1) in patients ≤2 years (P = .0511), but was similar between prosthesis sizes (P = .6). During follow-up period (median 7.6 years [IQR: 3.2-12.4], stroke occurred in 10%, prosthetic valve thrombosis requiring reoperation in 4%, endocarditis in 3%, and bleeding in 1%.

CONCLUSION

Early and late outcomes of mMVR in children are improved when performed at age >2 years and with prosthesis size ≥23 mm. These factors should be considered in the timing of mMVR.