Browsing by Subject "RECONSTRUCTION"

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  • Choque-Velasquez, Joham; Colasanti, Roberto; Rezai Jahromi, Behnam; Hernesniemi, Juha (2017)
    OBJECTIVE: The preservation of normal peri/intralesional bridging veins is extremely important in every micro-neurosurgical operation. The purpose of our study was to describe the "squeeze maneuver"assisted by indocyanine green videoangiography (ICGV), a simple technique to "resuscitate" partially occluded bridging veins during microneurosurgical operations. METHODS: When a bridging vein is inadvertently stretched up to its collapse during microneurosurgical procedures, a precise identification of the partially occluded zone is carried out under high magnification (10-153), as well as with the aid of the ICGV. If a continuous irrigation with isotonic saline solution does not allow one to reestablish the venous flow, the "squeeze maneuver" is carried out. This consists of squeezing and sliding with the bipolar forceps the occluded vessel along the normal venous flow direction. This procedure is repeated several times, while a continuous saline irriga-tion is applied. The ICGV is performed to confirm an adequate patency of the vein. RESULTS: This maneuver permits to restore the normal diameter of the vein and blood flow inside it. CONCLUSION: The "squeeze maneuver"assisted by ICGV represents a safe, clean, fast, and even cheap method for restoring the flow of partially occluded bridging veins during microneurosurgical operations.
  • Mäkitie, Antti; Kamali, Alexander; Mroueh, Rayan; Lindford, Andrew; Koivunen, Petri; Autio, Timo; Lassus, Patrik; Halle, Martin; Bäck, Leif; Palmgren, Björn; Hammarstedt-Nordenvall, Lalle (2020)
    Background and aims: Stage II cancer of the tongue is mostly managed surgically both locally and regionally. However, indications for postoperative radiotherapy and reconstructive options vary between centers. This paper aims to describe differences in treatment in a geographically homogenous cohort. Methods: A retrospective comparison was made between two cohorts of clinical T2N0 tongue cancer from Finland and Sweden. The Finnish cohort included 75 patients and the Swedish 54. All patients had curative intent of treatment and no previous head and neck cancer. Data analyzed consisted of pathological stage, size and thickness of tumor, frequency of reconstruction, radiotherapy delivered, and survival. Results: The Finnish cohort included a higher proportion of patients managed with reconstructive surgery (67%) than the Swedish cohort (0%), p <.00001. More patients were treated with postoperative radiotherapy (84%) in the Swedish cohort than in the Finnish (54%), p <.0002. The Finnish cohort had a higher level of survival and included more frequent downstaging (cTNM to pTNM).
  • Nousiainen, Jalo; Rajani, Chang; Kasper, Markus; Helin, Tapio (2021)
    Reinforcement learning (RL) presents a new approach for controlling adaptive optics (AO) systems for Astronomy. It promises to effectively cope with some aspects often hampering AO performance such as temporal delay or calibration errors. We formulate the AO control loop as a model-based RL problem (MBRL) and apply it in numerical simulations to a simple Shack-Hartmann Sensor (SHS) based AO system with 24 resolution elements across the aperture. The simulations show that MBRL controlled AO predicts the temporal evolution of turbulence and adjusts to mis-registration between deformable mirror and SHS which is a typical calibration issue in AO. The method learns continuously on timescales of some seconds and is therefore capable of automatically adjusting to changing conditions. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
  • Sandberg, Lars Johan; Tonseth, Kim A.; Kloster-Jensen, Kristine; Liu, Jun; Robe, Charee; Reece, Gregory; Hansen, Elisabeth H.; Berntsen, Karin; Halle, Martin; Edsander-Nord, Asa; Höckerstedt, Anna; Kauhanen, Susanna; Sneistrup, Christian; Tindholdt, Tyge; Petter Gullestad, Hans; Gunnarsson, Gudjon Leifur; Berg, Erik; Creed Selber, Jesse (2020)
    Background: There is little consensus about the relative determinative value of each individual factor in female breast aesthetics. When performing breast surgery with an aesthetic goal, certain factors will be more important than others. The purpose of this study was to make an aesthetic factor rank list to determine the relative contributions to overall breast aesthetics. Method: Volunteers were scanned using the 3-dimensional Vectra system. Ten Scandinavian plastic surgeons rated 37 subjects, using a validated scoring system with 49 scoring items. The correlation between specific aesthetic factors and overall breast aesthetic scores of the subjects were calculated using Pearson's r, Spearman's rho, and Kendall's tau. Results: A very strong correlation was found between overall breast aesthetic score and lower pole shape (0.876, P <0.0001). This was also true for upper pole shape (0.826, P <0.0001) and breast height (0.821, P <0.0001). A strong correlation was found between overall breast aesthetic score and nipple position (0.733, P <0.0001), breast size (0.644, P <0.0001), and breast width (0.632, P <0.0001). Factors that were only moderately correlated with aesthetic score were intermammary distance (0.496, P = 0.002), nipple size and projection (0.588, P <0.0001), areolar diameter (0.484, P <0.0001), and areolar shape (0.403, P <0.0001). Perceived symmetry was a weak factor (0.363, P = 0.027). Conclusions: Aesthetic factors of the female breast can be ranked in a priority list. Shape of the lower pole and upper pole and breast height are primary factors of female breast aesthetics. These should be prioritized in any aesthetic breast surgery. Vertical dimensional factors seem to be more determinative than horizontal factors.
  • Tanhuanpää, Topi; Kankare, Ville; Setälä, Heikki; Yli-Pelkonen, Vesa; Vastaranta, Mikko; Niemi, Mikko T.; Raisio, Juha; Holopainen, Markus (2017)
    Assessment of the amount of carbon sequestered and the value of ecosystem services provided by urban trees requires reliable data. Predicting the proportions and allometric relationships of individual urban trees with models developed for trees in rural forests may result in significant errors in biomass calculations. To better understand the differences in biomass accumulation and allocation between urban and rural trees, two existing biomass models for silver birch (Betula pendula Roth) were tested for their performance in assessing the above-ground biomass (AGB) of 12 urban trees. In addition, the performance of a volume-based method utilizing accurate terrestrial laser scanning (TLS) data and stem density was evaluated in assessing urban tree AGB. Both tested models underestimated the total AGB of single trees, which was mainly due to a substantial underestimation of branch biomass. The volume-based method produced the most accurate estimates of stem biomass. The results suggest that biomass models originally based on sample trees from rural forests should not be used for urban, open-grown trees, and that volume-based methods utilizing TLS data are a promising alternative for non-destructive assessment of urban tree AGB. (C) 2017 Elsevier GmbH. All rights reserved.
  • Saarinen, Ninni; Kankare, Ville; Pyorala, Jiri; Yrttimaa, Tuomas; Liang, Xinlian; Wulder, Michael A.; Holopainen, Markus; Hyyppa, Juha; Vastaranta, Mikko (2019)
    Large and comprehensive datasets, traditionally based on destructive stem analysis or other labor-intensive approaches, are commonly considered as a necessity in developing stem-volume equations. The aim here was to investigate how a decreasing number of sample trees affects parametrizing an existing taper curve equation and resultant stem-volume estimates. Furthermore, the potential of terrestrial laser scanning (TLS) in producing taper curves was examined. A TLS-based taper curve was derived for 246 Scots pines (Pinus sylvestris L.) from southern Finland to parametrize an existing taper curve equation. To assess sensitivity of the parametrization regarding sample size, the number of Scots pines included in the parametrization varied between full census and 1 Scots pine at a time. Root mean square error of stem-volume estimates remained = 46 Scots pines. Thus, it can be concluded that, with a rather small sample size, a taper curve equation can be re-parametrized for local conditions using point clouds from TLS to produce consistent stem-volume estimates.
  • Oinonen, Markku; Alenius, Teija; Arppe, Laura; Bocherens, Hervé; Etu-Sihvola, Heli; Helama, Samuli; Huhtamaa, Heli; Lahtinen, Maria; Mannermaa, Kristiina; Onkamo, Päivi; Palo, Jukka; Sajantila, Antti; Salo, Kati; Sundell, Tarja; Vanhanen, Santeri; Wessman, Anna (2020)
    Levanluhta is a unique archaeological site with the remains of nearly a hundred Iron Age individuals found from a water burial in Ostrobothnia, Finland. The strongest climatic downturn of the Common Era, resembling the great Fimbulvinter in Norse mythology, hit these people during the 6th century AD. This study establishes chronological, dietary, and livelihood synthesis on this population based on stable carbon and nitrogen isotopic and radiocarbon analyses on human remains, supported by multidisciplinary evidence. Extraordinarily broad stable isotopic distribution is observed, indicating three subgroups with distinct dietary habits spanning four centuries. This emphasizes the versatile livelihoods practiced at this boundary of marine, freshwater, and terrestrial ecosystems. While the impact of the prolonged cold darkness of the 6th century was devastating for European communities relying on cultivation, the broad range of livelihoods provided resilience for the Levanluhta people to overcome the abrupt climatic decline.
  • Nicolle, Marie; Debret, Maxime; Massei, Nicolas; Colin, Christophe; deVernal, Anne; Divine, Dmitri; Werner, Jojannes P.; Hormes, Anne; Korhola, Atte Antero; Linderholm, Hans W. (2018)
    To put recent climate change in perspective, it is necessary to extend the instrumental climate records with proxy data from paleoclimate archives. Arctic climate variability for the last 2 millennia has been investigated using statistical and signal analyses from three regionally averaged records from the North Atlantic, Siberia and Alaska based on many types of proxy data archived in the Arctic 2k database v1.1.1. In the North Atlantic and Alaska, the major climatic trend is characterized by long-term cooling interrupted by recent warming that started at the beginning of the 19th century. This cooling is visible in the Siberian region at two sites, warming at the others. The cooling of the Little Ice Age (LIA) was identified from the individual series, but it is characterized by wide-range spatial and temporal expression of climate variability, in contrary to the Medieval Climate Anomaly. The LIA started at the earliest by around AD 1200 and ended at the latest in the middle of the 20th century. The widespread temporal coverage of the LIA did not show regional consistency or particular spatial distribution and did not show a relationship with archive or proxy type either. A focus on the last 2 centuries shows a recent warming characterized by a well-marked warming trend parallel with increasing greenhouse gas emissions. It also shows a multidecadal variability likely due to natural processes acting on the internal climate system on a regional scale. A similar to 16-30-year cycle is found in Alaska and seems to be linked to the Pacific Decadal Oscillation, whereas similar to 20-30- and similar to 50-90-year periodicities characterize the North Atlantic climate variability, likely in relation with the Atlantic Multidecadal Oscillation. These regional features are probably linked to the sea ice cover fluctuations through ice-temperature positive feedback.
  • The ATLAS collaboration; The CMS collaboration; Aad, G.; Aaboud, M.; Sirunyan, A. M.; Eerola, P.; Kirschenmann, H.; Pekkanen, J.; Voutilainen, M.; Havukainen, J.; Heikkilä, J. K.; Järvinen, T.; Karimäki, V.; Kinnunen, R.; Lampén, T.; Lassila-Perini, K.; Laurila, S.; Lehti, S.; Lindén, T.; Luukka, P.; Mäenpää, T.; Siikonen, H.; Tuominen, E.; Tuominiemi, J.; Tuuva, T. (2019)
    This paper presents the combinations of single-top-quark production cross-section measurements by the ATLAS and CMS Collaborations, using data from LHC proton-proton collisions at = 7 and 8 TeV corresponding to integrated luminosities of 1.17 to 5.1 fb(-1) at = 7 TeV and 12.2 to 20.3 fb(-1) at = 8 TeV. These combinations are performed per centre-of-mass energy and for each production mode: t-channel, tW, and s-channel. The combined t-channel cross-sections are 67.5 +/- 5.7 pb and 87.7 +/- 5.8 pb at = 7 and 8 TeV respectively. The combined tW cross-sections are 16.3 +/- 4.1 pb and 23.1 +/- 3.6 pb at = 7 and 8 TeV respectively. For the s-channel cross-section, the combination yields 4.9 +/- 1.4 pb at = 8 TeV. The square of the magnitude of the CKM matrix element V-tb multiplied by a form factor f(LV) is determined for each production mode and centre-of-mass energy, using the ratio of the measured cross-section to its theoretical prediction. It is assumed that the top-quark-related CKM matrix elements obey the relation |V-td|, |V-ts| << |V-tb|. All the |f(LV)V(tb)|(2) determinations, extracted from individual ratios at = 7 and 8 TeV, are combined, resulting in |f(LV)V(tb)| = 1.02 +/- 0.04 (meas.) +/- 0.02 (theo.). All combined measurements are consistent with their corresponding Standard Model predictions.
  • Pyörälä, Jiri; Kankare, Ville; Vastaranta, Mikko; Rikala, Juha; Holopainen, Markus; Sipi, Marketta; Hyyppä, Juha; Uusitalo, Jori (2018)
    While X-ray scanning is increasingly used to measure the interior quality of logs, terrestrial laser scanning (TLS) could be used to collect information on external tree characteristics. As branches are one key indicator of wood quality, we compared TLS and X-ray scanning data in deriving whorl locations and each whorl's maximum branch and knot diameters for 162 Scots pine (Pinus sylvestris L.) log sections. The mean number of identified whorls per tree was 37.25 and 22.93 using X-ray and TLS data, respectively. The lowest TLS-derived whorl in each sample tree was an average 5.56 m higher than that of the X-ray data. Whorl-to-whorl mean distances and the means of the maximum branch and knot diameters in a whorl measured for each sample tree using TLS and X-ray data had mean differences of -0.12 m and -6.5 mm, respectively. One of the most utilized wood quality indicators, tree-specific maximum knot diameter measured by X-ray, had no statistically significant difference to the tree-specific maximum branch diameter measured from the TLS point cloud. It appears challenging to directly derive comparative branch structure information using TLS and X-ray. However, some features that are extractable from TLS point clouds are potential wood quality indicators.
  • Rasilainen, S. K.; Mentula, P. J.; Leppaniemi, A. K. (2016)
    Background and aims: The goal after open abdomen treatment is to reach primary fascial closure. Modern negative pressure wound therapy systems are sometimes inefficient for this purpose. This retrospective chart analysis describes the use of the components separation' method in facilitating primary fascial closure after open abdomen. Material and methods: A total of 16 consecutive critically ill surgical patients treated with components separation during open abdomen management were analyzed. No patients were excluded. Results: Primary fascial closure was achieved in 75% (12/16). Components separation was performed during ongoing open abdomen treatment in 7 patients and at the time of delayed primary fascial closure in 9 patients. Of the former, 3/7 (43%) patients reached primary fascial closure, whereas all 9 patients in the latter group had successful fascial closure without major complications (p=0.019). Conclusion: Components separation is a useful method in contributing to successful primary fascial closure in patients treated for open abdomen. Best results were obtained when components separation was performed simultaneously with primary fascial closure at the end of the open abdomen treatment.
  • Rintala, Risto J. (2016)
    Persistent cloaca remains a challenge for pediatric surgeons and urologists. Reconstructive surgery of cloacal malformations aims to repair the anorectum, urinary tract, and genital organs, and achieve fecal and urinary continence as well as functional genital tract capable for sexual activity and pregnancy. Unfortunately, even in most experienced hands these goals are not always accomplished. The endpoint of the functional development of bowel, urinary, and genital functions is the completion of patient's growth and sexual maturity. It is unlikely that there will be any significant functional improvement beyond these time points. About half of the patients with cloaca attain fecal and urinary continence after their growth period. The remaining half stay clean or dry by adjunctive measures such as bowel management by enemas or ACE channel, and continent urinary diversion or intermittent catheterization. Problems related to genital organs such as obstructed menstruations, amenorrhea, and introitus stenosis are common and often require secondary surgery. Encouragingly, most adolescent and adult patients are capable of sexual life despite often complex vaginal primary and secondary reconstructions. Also, cloacal malformation does not preclude pregnancies, although they still are quite rare. Pregnant patients with cloaca require special care and follow-up to guarantee uncomplicated pregnancy and preservation of anorectal and urinary functions. Cesarean section is recommended for cloaca patients. The self-reported quality of life of cloaca patients appears to be comparable to that of female patients with less complex anorectal malformations. (C) 2016 Elsevier Inc. All rights reserved.
  • Akmal, Jan Sher; Salmi, Mika; Hemming, Björn; Teir, Linus; Suomalainen, Anni; Kortesniemi, Mika; Partanen, Jouni; Lassila, Antti (2020)
    Featured Application Accuracy of additively manufactured implants for clinical surgery. Abstract In craniomaxillofacial surgical procedures, an emerging practice adopts the preoperative virtual planning that uses medical imaging (computed tomography), 3D thresholding (segmentation), 3D modeling (digital design), and additive manufacturing (3D printing) for the procurement of an end-use implant. The objective of this case study was to evaluate the cumulative spatial inaccuracies arising from each step of the process chain when various computed tomography protocols and thresholding values were independently changed. A custom-made quality assurance instrument (Phantom) was used to evaluate the medical imaging error. A sus domesticus (domestic pig) head was analyzed to determine the 3D thresholding error. The 3D modeling error was estimated from the computer-aided design software. Finally, the end-use implant was used to evaluate the additive manufacturing error. The results were verified using accurate measurement instruments and techniques. A worst-case cumulative error of 1.7 mm (3.0%) was estimated for one boundary condition and 2.3 mm (4.1%) for two boundary conditions considering the maximum length (56.9 mm) of the end-use implant. Uncertainty from the clinical imaging to the end-use implant was 0.8 mm (1.4%). This study helps practitioners establish and corroborate surgical practices that are within the bounds of an appropriate accuracy for clinical treatment and restoration.
  • JET Contributors; Mlynar, Jan; Ahlgren, T.; Aho-Mantila, L.; Airila, M.; Björkas, C.; Jarvinen, A.; Lahtinen, A.; Makkonen, T.; Nordlund, K.; Safi, E.; Sipila, S. K.; Asunta, O.; Groth, M.; Hakola, A.; Karhunen, J.; Koivuranta, S.; Koskela, T.; Kurki-Suonio, T.; Lomanowski, B.; Lonnroth, J.; Salmi, A.; Santala, M. I. K. (2019)
    Retrieving spatial distribution of plasma emissivity from line integrated measurements on tokamaks presents a challenging task due to ill-posedness of the tomography problem and limited number of the lines of sight. Modern methods of plasma tomography therefore implement a-priori information as well as constraints, in particular some form of penalisation of complexity. In this contribution, the current tomography methods under development (Tikhonov regularisation, Bayesian methods and neural networks) are briefly explained taking into account their potential for integration into the fusion reactor diagnostics. In particular, current development of the Minimum Fisher Regularisation method is exemplified with respect to real-time reconstruction capability, combination with spectral unfolding and other prospective tasks.
  • Lassas, Matti; Saksala, Teemu (2019)
    Let (N, g) be a Riemannian manifold with the distance function d(x, y) and an open subset M subset of N. For x is an element of M we denote by D-x the distance difference function D-x:F x F -> R, given by D-x(z(1), z(2)) = d(x, z(1)) - d(x, z(2)), z(1), z(2) is an element of F = N \ M. We consider the inverse problem of determining the topological and the differentiable structure of the manifold M and the metric g vertical bar M on it when we are given the distance difference data, that is, the set F, the metric g vertical bar F, and the collection D(M) = {D-x; x is an element of M}. Moreover, we consider the embedded image D(M) of the manifold M, in the vector space C(F x F), as a representation of manifold M. The inverse problem of determining (M, g) from D(M) arises e.g. in the study of the wave equation on R x N when we observe in F the waves produced by spontaneous point sources at unknown points (t, x) is an element of R x M. Then D-x (z(1), z(2)) is the difference of the times when one observes at points z(1) and z(2) the wave produced by a point source at x that goes off at an unknown time. The problem has applications in hybrid inverse problems and in geophysical imaging.
  • Hyytiäinen, Heli K.; Mölsä, Sari H.; Junnila, Jouni J. T.; Laitinen-Vapaavuori, Outi M.; Hielm-Björkman, Anna K. (2018)
    This study aimed at developing a quantitative testing battery for dogs' stifle functionality, as, unlike in human medicine, currently none is available in the veterinary field. Forty-three dogs with surgically treated unilateral cranial cruciate ligament rupture and 21 dogs with no known musculoskeletal problems were included. Eight previously studied tests: compensation in sitting and lying positions, symmetry of thrust in hindlimbs when rising from lying and sitting, static weight bearing, stifle flexion and extension and muscle mass symmetry, were summed into the Finnish Canine Stifle Index (FCSI). Sensitivities and specificities of the dichotomised FCSI score were calculated against orthopaedic examination, radiological and force platform analysis and a conclusive assessment (combination of previous). One-way analysis of variance (ANOVA)was used to evaluate FCSI score differences between the groups. Cronbach's alpha for internal consistency was calculated. The range of the index score was 0-263, with a proposed cut-off value of 60 between 'adequate' and 'compromised' functional performance. In comparison to the conclusive assessment, the sensitivity and specificity of the FCSI were 90 per cent and 90.5 per cent, respectively. Cronbach's alpha for internal reliability of the FCSI score was 0.727. An estimate of the surgically treated and control dogs' FCSI scores were 105 (95 per cent CI 93 to 116) and 20 (95 per cent CI 4 to 37), respectively. The difference between the groups was significant (P
  • Hauptmann, Andreas; Santacesaria, Matteo; Siltanen, Samuli (2017)
    In electrical impedance tomography (EIT) one wants to image the conductivity distribution of a body from current and voltage measurements carried out on its boundary. In this paper we consider the underlying mathematical model, the inverse conductivity problem, in two dimensions and under the realistic assumption that only a part of the boundary is accessible to measurements. In this framework our data are modeled as a partial Neumann-to-Dirichlet map (ND map). We compare this data to the full-boundary ND map and prove that the error depends linearly on the size of the missing part of the boundary. The same linear dependence is further proved for the difference of the reconstructed conductivities-from partial and full boundary data. The reconstruction is based on a truncated and linearized D-bar method. Auxiliary results include an extrapolation method to estimate the full-boundary data from the measured one, an approximation of the complex geometrical optics solutions computed directly from the ND map as well as an approximate scattering transform for reconstructing the conductivity. Numerical verification of the convergence results and reconstructions are presented for simulated test cases.
  • Korpela, Jussi; Lassas, Matti; Oksanen, Lauri (2019)
    An inverse boundary value problem for the 1+1 dimensional wave equation (partial derivative(2)(t) - c(x)(2)partial derivative(2)(x))u(x,t) = 0, x is an element of R+ is considered. We give a discrete regularization strategy to recover wave speed c(x) when we are given the boundary value of the wave, u(0,t), that is produced by a single pulse-like source. The regularization strategy gives an approximative wave speed (c) over tilde, satisfying a Holder type estimate parallel to (c) over tilde - c parallel to
  • Heikkila, Maria; Mutanen, Marko; Wahlberg, Niklas; Sihvonen, Pasi; Kaila, Lauri (2015)
    Background: Ditrysia comprise close to 99 % of all butterflies and moths. The evolutionary relationships among the ditrysian superfamilies have received considerable attention in phylogenetic studies based on DNA and transcriptomic data, but the deepest divergences remain for large parts unresolved or contradictory. To obtain complementary insight into the evolutionary history of the clade, and to test previous hypotheses on the subdivision of Ditrysia based on morphology, we examine the morphology of larvae, pupae and adult males and females of 318 taxa representing nearly all ditrysian superfamilies and families. We present the most comprehensive morphological dataset on Ditrysia to date, consisting of over 500 morphological characters. The data are analyzed alone and combined with sequence data (one mitochondrial and seven nuclear protein-coding gene regions, sequenced from 422 taxa). The full dataset consists of 473 exemplar species. Analyses are performed using maximum likelihood methods, and parsimony methods for the morphological dataset. We explore whether combining morphological data and DNA-data can stabilize taxa that are unstable in phylogenetic studies based on genetic data only. Results: Morphological characters are found phylogenetically informative in resolving apical nodes (superfamilies and families), but characters serving as evidence of relatedness of larger assemblages are few. Results include the recovery of a monophyletic Tineoidea, Sesioidea and Cossoidea, and a stable position for some unstable taxa (e.g. Epipyropidae, Cyclotornidae, Urodoidea + Schreckensteinioidea). Several such taxa, however, remain unstable even though morphological characters indicate a position in the tree (e.g. Immidae). Evidence supporting affinities between clades are suggested, e.g. a novel larval synapomorphy for Tineidae. We also propose the synonymy of Tineodidae with Alucitidae, syn. nov. Conclusions: The large morphological dataset provides information on the diversity and distribution of morphological traits in Ditrysia, and can be used in future research on the evolution of these traits, in identification keys and in identification of fossil Lepidoptera. The "backbone" of the phylogeny for Ditrysia remains largely unresolved. As previously proposed as an explanation for the scarcity of molecular signal in resolving the deeper nodes, this may be due to the rapid radiation of Ditrysia in the Cretaceous.