Millimeter wave-based patient setup verification and motion tracking during radiotherapy

BACKGROUND

Position verification and motion monitoring are critical for safe and precise radiotherapy (RT). Existing approaches to these tasks based on visible light or x-ray are suboptimal either because they cannot penetrate obstructions to the patient's skin or introduce additional radiation exposure. The low-cost mmWave radar is an ideal solution for these tasks as it can monitor patient position and motion continuously throughout the treatment delivery.

PURPOSE

To develop and validate frequency-modulated continuous wave (FMCW) mmWave radars for position verification and motion tracking during RT delivery.

METHODS

A 77 GHz FMCW mmWave module was used in this study. Chirp Z Transform-based (CZT) algorithm was developed to process the intermediate frequency (IF) signals. Absolute distances to flat Solid Water slabs and human shape phantoms were measured. The accuracy of absolute distance and relative displacement were evaluated.

RESULTS

Without obstruction, mmWave based on the CZT algorithm was able to detect absolute distance within 1 mm for a Solid Water slab that simulated the reflectivity of the human body. Through obstructive materials, the mmWave device was able to detect absolute distance within 5 mm in the worst case and within 3.5 mm in most cases. The CZT algorithm significantly improved the accuracy of absolute distance measurement compared with Fast Fourier Transform (FFT) algorithm and was able to achieve submillimeter displacement accuracy with and without obstructions. The surface-to-skin distance (SSD) measurement accuracy was within 8 mm in the anterior of the phantom.

CONCLUSIONS

With the CZT signal processing algorithm, the mmWave radar is able to measure the absolute distance to a flat surface within 1 mm. But the absolute distance measurement to a human shape phantom is as large as 8 mm at some angles. Further improvement is necessary to improve the accuracy of SSD measurement to uneven surfaces by the mmWave radar.

A Dose Accumulation Assessment of Alignment Errors During Spatially Fractionated Radiation Therapy

PURPOSE

Spatially fractionated radiation therapy (SFRT) techniques produce high-dose peaks and low-dose valleys within a tumor. Lattice stereotactic body radiation therapy (SBRT) is a form a SFRT delivered across 5 fractions. Because of the high spatial dose gradients associated with SFRT, it is critical for fractionated SFRT patients to be aligned correctly for treatment. Here we investigate the dosimetric effect of daily alignment uncertainty through a dose accumulation study.

METHODS AND MATERIALS

Dose accumulation was retrospectively performed for 10 patients enrolled on a phase 1 trial. Lattice stereotactic body radiation therapy was completed in 5 fractions with 20 Gy prescribed to the entire tumor and a simultaneous integrated boost of 66.7 Gy prescribed to a set of regularly spaced high-dose spheres. Daily alignment error was quantified through manually selected landmarks in both the planning computed tomography scan and daily cone beam computed tomography. The dosimetric effect of alignment errors was quantified by translating the isocenter in the treatment planning system by the daily average alignment error. Large errors were simulated by translating isocenter 5 and 10 mm for 1 and 2 fractions, independently assessing errors in the superior-inferior and axial directions. The reduction of dose gradients was quantified using the dose ratio (DR) of the mean dose in the high-dose and low-dose spheres.

RESULTS

The average alignment error was 1.8 mm across the patient population resulting in minor smoothing of the high- and low-dose distributions in the dose accumulation. Quantitatively, the DR decreased from 3.42 to 3.32 (P = .093) in the dose accumulation study. The simulated worst case was an inferior-superior shift of 10 mm for 2 fractions where the average DR decreased to 2.72 (P = .0001).

CONCLUSIONS

The dose accumulation study revealed on average DR only decreased from 3.42 to 3.32. However, setup errors >5 mm resulted in larger dosimetric degradation, reflecting a larger effect for individual high-dose spheres within regions exhibiting larger displacements.

First treatments for Lattice stereotactic body radiation therapy using magnetic resonance image guided radiation therapy

Two abdominal patients were treated with Lattice stereotactic body radiation therapy (SBRT) using magnetic resonance guided radiation therapy (MRgRT). This is one of the first reported treatments of Lattice SBRT with the use of MRgRT. A description of the treatment approach and planning considerations were incorporated into this report. MRgRT Lattice SBRT delivered similar planning quality metrics to established dosimetric parameters for Lattice SBRT. Increased signal intensity were seen in the MRI treatments for one of the patients during the course of treatment.

Phantom-based Quality Assurance of a Clinical Dose Accumulation Technique Used in an Online Adaptive Radiation Therapy Platform

Purpose

This study aimed to develop a routine quality assurance method for a dose accumulation technique provided by a radiation therapy platform for online treatment adaptation.

Methods and Materials

Two commonly used phantoms were selected for the dose accumulation QA: Electron density and anthropomorphic pelvis. On a computed tomography (CT) scan of the electron density phantom, 1 target (gross tumor volume [GTV]; insert at 6 o'clock), a subvolume within this target, and 7 organs at risk (OARs; other inserts) were contoured in the treatment planning system (TPS). Two adaptation sessions were performed in which the GTV was recontoured, first at 7 o'clock and then at 5 o'clock. The accumulated dose was exported from the TPS after delivery. Deformable vector fields were also exported to manually accumulate doses for comparison. For the pelvis phantom, synthetic Gaussian deformations were applied to the planning CT image to simulate organ changes. Two single-fraction adaptive plans were created based on the deformed planning CT and cone beam CT images acquired onboard the radiation therapy platform. A manual dose accumulation was performed after delivery using the exported deformable vector fields for comparison with the system-generated result.

Results

All plans were successfully delivered, and the accumulated dose was both manually calculated and derived from the TPS. For the electron density phantom, the average mean dose differences in the GTV, boost volume, and OARs 1 to 7 were 0.0%, -0.2%, 92.0%, 78.4%, 1.8%, 1.9%, 0.0%, 0.0%, and 2.3%, respectively, between the manually summed and platform-accumulated doses. The gamma passing rates for the 3-dimensional dose comparison between the manually generated and TPS-provided dose accumulations were >99% for both phantoms.

Conclusions

This study demonstrated agreement between manually obtained and TPS-generated accumulated doses in terms of both mean structure doses and local 3-dimensional dose distributions. Large disagreements were observed for OAR1 and OAR2 defined on the electron density phantom due to OARs having lower deformation priority over the target in addition to artificially large changes in position induced for these structures fraction-by-fraction. The tests applied in this study to a commercial platform provide a straightforward approach toward the development of routine quality assurance of dose accumulation in online adaptation.

Standards of Care for the Health of Transgender and Gender Diverse People, Version 8

Background: Transgender healthcare is a rapidly evolving interdisciplinary field. In the last decade, there has been an unprecedented increase in the number and visibility of transgender and gender diverse (TGD) people seeking support and gender-affirming medical treatment in parallel with a significant rise in the scientific literature in this area. The World Professional Association for Transgender Health (WPATH) is an international, multidisciplinary, professional association whose mission is to promote evidence-based care, education, research, public policy, and respect in transgender health. One of the main functions of WPATH is to promote the highest standards of health care for TGD people through the Standards of Care (SOC). The SOC was initially developed in 1979 and the last version (SOC-7) was published in 2012. In view of the increasing scientific evidence, WPATH commissioned a new version of the Standards of Care, the SOC-8. Aim: The overall goal of SOC-8 is to provide health care professionals (HCPs) with clinical guidance to assist TGD people in accessing safe and effective pathways to achieving lasting personal comfort with their gendered selves with the aim of optimizing their overall physical health, psychological well-being, and self-fulfillment. Methods: The SOC-8 is based on the best available science and expert professional consensus in transgender health. International professionals and stakeholders were selected to serve on the SOC-8 committee. Recommendation statements were developed based on data derived from independent systematic literature reviews, where available, background reviews and expert opinions. Grading of recommendations was based on the available evidence supporting interventions, a discussion of risks and harms, as well as the feasibility and acceptability within different contexts and country settings. Results: A total of 18 chapters were developed as part of the SOC-8. They contain recommendations for health care professionals who provide care and treatment for TGD people. Each of the recommendations is followed by explanatory text with relevant references. General areas related to transgender health are covered in the chapters Terminology, Global Applicability, Population Estimates, and Education. The chapters developed for the diverse population of TGD people include Assessment of Adults, Adolescents, Children, Nonbinary, Eunuchs, and Intersex Individuals, and people living in Institutional Environments. Finally, the chapters related to gender-affirming treatment are Hormone Therapy, Surgery and Postoperative Care, Voice and Communication, Primary Care, Reproductive Health, Sexual Health, and Mental Health. Conclusions: The SOC-8 guidelines are intended to be flexible to meet the diverse health care needs of TGD people globally. While adaptable, they offer standards for promoting optimal health care and guidance for the treatment of people experiencing gender incongruence. As in all previous versions of the SOC, the criteria set forth in this document for gender-affirming medical interventions are clinical guidelines; individual health care professionals and programs may modify these in consultation with the TGD person.

DANSR: A Tool for the Detection of Annotated and Novel Small RNAs

Existing small noncoding RNA analysis tools are optimized for processing short sequencing reads (17-35 nucleotides) to monitor microRNA expression. However, these strategies under-represent many biologically relevant classes of small noncoding RNAs in the 36-200 nucleotides length range (tRNAs, snoRNAs, etc.). To address this, we developed DANSR, a tool for the detection of annotated and novel small RNAs using sequencing reads with variable lengths (ranging from 17-200 nt). While DANSR is broadly applicable to any small RNA dataset, we applied it to a cohort of matched normal, primary, and distant metastatic colorectal cancer specimens to demonstrate its ability to quantify annotated small RNAs, discover novel genes, and calculate differential expression. DANSR is available as an open source tool.

Development and Implementation of an Open Source Template Interpretation Class Library for Automated Treatment Planning

PURPOSE

Widespread implementation of automated treatment planning in radiation therapy remains elusive due to variability in clinic and physician preferences making it difficult to ensure consistent plan parameters. We have developed an open-source class library with the aim to improve efficiency and consistency for automated treatment planning in radiation therapy.

METHODS AND MATERIALS

An open source class library has been developed that interprets clinical templates within a commercial treatment planning system into a treatment plan for automated planning. This code was leveraged for the automated planning of 39 patients and retrospectively compared to the 78 clinically approved manual plans.

RESULTS

From the initial 39 patients, 74 of 78 plans were successfully generated without manual intervention. Target dose was more homogenous for automated plans, with an average homogeneity index of 3.30 vs 3.11 for manual and automated plans, respectively (p = 0.107). Generalized equivalent uniform dose decreased in the femurs and rectum for automated plans, with mean gEUD of 3746 cGy vs 3338 cGy (p ≤ 0.001) and 5761 cGy vs 5634 cGy (p ≤ 0.001) for femurs and rectum, respectively. Dose metrics for bladder and rectum (V6500 cGy and V4000 cGy) show recognizable but insignificant improvements. All automated plans delivered for quality assurance passed a gamma analysis (>95%) with an average composite pass rate of 99.3% and 98.8% for pelvis and prostate plans, respectively. Deliverability parameters such as total monitor units and aperture complexity indicate deliverable plans.

CONCLUSIONS

Prostate cancer and pelvic node radiotherapy can be automated using VMAT planning and clinical templates based on a standardized clinical workflow. The class library developed in this study conveniently interfaces between the plan template and the treatment planning system to automatically generate high quality plans on customizable templates.

RADT-12. USE OF FDOPA PET FOR RADIATION THERAPY TARGETING IN GRADE 2 IDH MUTANT GLIOMA

BACKGROUND

Low-grade, IDH mutant (IDHmt) gliomas typically do not enhance on MRI complicating radiotherapy (RT) target delineation. Amino acid PET using 3,4-dihydroxy-6-[18F]-fluoro-L-phenylalanine (FDOPA) has demonstrated avidity in IDHmt gliomas and may assist in RT planning for non-enhancing tumors. This study aims to compare conventional and FDOPA-defined target volumes in grade 2 IDHmt gliomas.

METHODS

In a prospective pilot study, patients underwent MRI and FDOPA PET using a 3T MRI/PET system followed by standard therapy. Gross tumor volumes (GTV) included the T2/FLAIR abnormality and surgical cavity; clinical target volumes (CTV) included a 1 cm expansion constrained anatomically. Metabolic target volumes (MTVs) were generated using the FDOPA SUV > 1.5-fold normal brain isocurve. Union of GTV and MTV generated a fusion GTV (fGTV); expanding fGTV by 1 cm yielded the fusion CTV (fCTV). Target volumes were compared volumetrically with overlap (Dice coefficient) and surface metrics (Hausdorff distance). Medians are reported with ranges.

RESULTS

Four patients with grade 2 IDHmt glioma (3 1p/19q codeleted oligodendrogliomas, 1 non-codeleted astrocytoma) received MRI/PET before treatment. All oligodendrogliomas exhibited FDOPA avidity; the astrocytoma showed no avidity. GTV and CTV measured 16.1 cc (4.9 - 82.2 cc) and 76.7 cc (29.5 - 256.1 cc), respectively. The MTV volume outside of GTV was 0.8 cc (0.2 – 6.1 cc), but was covered in each case by the CTV. Addition of FDOPA increased fGTV and fCTV volumes by 5.4% and 17.5%, respectively. Dice coefficient and Hausdorff distances for GTV vs fGTV were 0.96 (0.95 - 0.99) and 11.2 mm (10.0 – 11.9 mm), respectively, and for CTV vs fCTV were 0.87 (0.81 – 0.95) and 10.2 mm (10.0 - 11.0), respectively.

CONCLUSIONS

FDOPA PET identified tracer-avid regions outside of MRI-defined GTVs in a group of IDHmt gliomas. FDOPA PET provides useful metabolic information for RT planning and warrants further investigation.

Dynamics and extensional rheology of polymer-surfactant association complexes

Understanding and characterizing the influence of polymers and surfactants on rheology, application, and processing is critical for designing complex fluid formulations for enhanced oil recovery, pharmaceuticals, cosmetics, foods, inks, agricultural sprays, and coatings. It is well-established that the addition of anionic surfactant like sodium dodecyl sulfate (SDS) to an aqueous solution of an oppositely-charged or uncharged polymer like poly(ethylene oxide) (PEO) can result in the formation of the polymer-surfactant association complexes (P0S-ACs) and a non-monotonic concentration-dependent variation in zero shear viscosity. However, the extensional rheology response of polymer-surfactant mixtures remains relatively poorly understood, partially due to characterization challenges that arise for low viscosity, low elasticity fluids, even though the response to strong extensional flows impacts drop formation and many processing operations. In this article, we use the recently developed dripping-onto-substrate (DoS) rheometry protocols to characterize the pinching dynamics and extensional rheology response of aqueous P0S- solutions formulated with PEO (P0) and SDS (S-), respectively. We find the PEO-SDS mixtures display a significantly weaker concentration-dependent variation in the extensional relaxation time, filament lifespan, and extensional viscosity values than anticipated by the measured shear viscosity.

Direct tumor visual feedback during free breathing in 0.35T MRgRT

To present a tumor motion control system during free breathing using direct tumor visual feedback to patients in 0.35 T magnetic resonance-guided radiotherapy (MRgRT). We present direct tumor visualization to patients by projecting real-time cine MR images on an MR-compatible display system inside a 0.35 T MRgRT bore. The direct tumor visualization included anatomical images with a target contour and an auto-segmented gating contour. In addition, a beam-status sign was added for patient guidance. The feasibility was investigated with a six-patient clinical evaluation of the system in terms of tumor motion range and beam-on time. Seven patients without visual guidance were used for comparison. Positions of the tumor and the auto-segmented gating contour from the cine MR images were used in probability analysis to evaluate tumor motion control. In addition, beam-on time was recorded to assess the efficacy of the visual feedback system. The direct tumor visualization system was developed and implemented in our clinic. The target contour extended 3 mm outside of the gating contour for 33.6 ± 24.9% of the time without visual guidance, and 37.2 ± 26.4% of the time with visual guidance. The average maximum motion outside of the gating contour was 14.4 ± 11.1 mm without and 13.0 ± 7.9 mm with visual guidance. Beam-on time as a percentage was 43.9 ± 15.3% without visual guidance, and 48.0 ± 21.2% with visual guidance, but was not significantly different (P = 0.34). We demonstrated the clinical feasibility and potential benefits of presenting direct tumor visual feedback to patients in MRgRT. The visual feedback allows patients to visualize and attempt to minimize tumor motion in free breathing. The proposed system and associated clinical workflow can be easily adapted for any type of MRgRT.

Long-term Inter-protocol kV CBCT image quality assessment for a ring-gantry linac via automated QA approach

We develop a fully automated QA process to compare the image quality of all kV CBCT protocols on a Halcyon linac with ring gantry design, and evaluate image quality stability over a 10-month period. A total of 19 imaging scan and reconstruction protocols were characterized with measurement on a newly released QUART phantom. A set of image analysis algorithms were developed and integrated into an automated analysis suite to derive key image quality metrics, including HU value accuracy on density inserts, HU uniformity using the background plate, high contrast resolution with the modulation transfer function (MTF) from the edge profiles, low contrast resolution using the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), slice thickness with the air gap modules, and geometric accuracy with the diameter of the phantom. Image quality data over 10 months was tracked and analyzed to evaluate the stability of the Halcyon kV imaging system. The HU accuracy over all 19 protocols is within tolerance (±50HU). The maximum uniformity deviation is 12.2 HU. The SNR and CNR, depending on the protocol selected, range from 18.5-911.9 and 1.9-102.8, respectively. A much-improved SNR and CNR were observed for iterative reconstruction (iCBCT) modes and protocols designed for large subjects over low dose and fast scanning modes. The Head and Image Gently protocols have the greatest high contrast resolution with MTF_10% over 1 lp/mm and MTF_50% over 0.6 lp/mm. The iCBCT mode slightly improved the MTF_10% and MTF_50% compared to the Feldkamp-Davis-Kress approach. The slice thickness (maximum error of 0.31 mm) and geometry metrics (maximum error of 0.7 mm) are all within tolerance (±0.5 mm for slice thickness and ±1 mm for geometry metrics). The long-term study over 10-month showed no significant drift for all key image quality metrics, which indicated the kV CBCT image quality is stable over time.

The impact of mass density variations on an electron Monte Carlo algorithm for radiotherapy dose calculations

Background and Purpose

A key step in electron Monte Carlo dose calculation requires converting Computed Tomography (CT) numbers from a tomographic acquisition to a mass density. This study investigates the dosimetric consequences of perturbations applied to a calibration table between CT number and mass density.

Materials and Methods

A literature search was performed to define lower and upper bounds for physically reasonable perturbations to a reference CT number to mass density calibration table. Electron beam dose was calculated for ten patients using these variations and the results were compared to clinical plans originally derived with a reference calibration table. Dose differences both globally and in the Planning Target Volume (PTV) were assessed using dose- and volume-based metrics and 3- dimensional gamma analysis for each patient.

Results

Small but statistically significant differences were observed between perturbations and reference data for certain metrics including volume of the 50% prescription isodose. Upper and lower variations in CT number to mass density calibration yielded mean values of V50% that were 4.4% larger and 2.1% smaller than reference values respectively. Gamma analysis using 3%/3mm criteria indicated >99% passing rate for the PTV for all patients. Global gamma analysis for some patients showed larger discrepancies possibly due to large electron path lengths through inhomogeneities.

Conclusions

In most patients, physically reasonable perturbations in CT number to mass density curves will not induce clinically significant impact on calculated target dose distributions. Strong dependence of electron transport on voxel material may produce dose speckle throughout the volume. Care should be taken in evaluating critical structures at depths beyond the target volume in highly heterogeneous regions.

Two-and-a-half-year clinical experience with the world's first magnetic resonance image guided radiation therapy system

Purpose

Magnetic resonance image guided radiation therapy (MR-IGRT) has been used at our institution since 2014. We report on more than 2 years of clinical experience in treating patients with the world's first MR-IGRT system.

Methods and materials

A clinical service was opened for MR-IGRT in January 2014 with an MR-IGRT system consisting of a split 0.35T magnetic resonance scanner that straddles a ring gantry with 3 multileaf collimator-equipped ⁶⁰Co heads. The service was expanded to include online adaptive radiation therapy (ART) MR-IGRT and cine gating after 6 and 9 months, respectively. Patients selected for MR-IGRT were enrolled in a prospective registry between January 2014 and June 2016. Patients were treated with a variety of radiation therapy techniques including intensity modulated radiation therapy and stereotactic body radiation therapy (SBRT). When applicable, online ART was performed and gating on sagittal 2-dimensional cine MR was used. The charts of patients treated with MR-IGRT were reviewed to report on the clinical and treatment characteristics of the initial patients who were treated with this novel technique.

Results

A total of 316 patients have been treated with the MR-IGRT system, which has been integrated into a high-volume clinic. The cases were most commonly selected for improved soft tissue visualization, ART, and cine gating. Seventy-six patients were treated with 3-dimensional conformal radiation therapy, 146 patients with intensity modulated radiation therapy, and 94 patients with SBRT. The most commonly treated disease sites were the abdomen (28%), breast (26%), pelvis (22%), thorax (19%), and head and neck (5%). Sixty-seven patients were treated with online ART over a total of 244 adapted fractions. Cine treatment gating was used for a total of 81 patients.

Conclusions

MR-IGRT has been successfully implemented in a high-volume radiation clinic and provides unique advantages in the treatment of a variety of malignancies. Additional clinical trials are in development to formally evaluate MR-IGRT in the treatment of multiple disease sites with techniques such as SBRT and ART.

A treatment planning comparison of proton therapy and intensity-modulated radiotherapy (IMRT) for prostate cancer using the normal tissue complication probability (NTCP)

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Background: The volume of rectum receiving high-dose (i.e. > or = 60 Gy) is consistently associated with the risk of Grade > or = 2 rectal toxicity or rectal bleeding based on common terminology criteria for adverse events (CTCAE). Our goal was to compare intensity-modulated photon radiotherapy (IMRT) with proton radiotherapy in regard to the rectal dose using the normal tissue complication probability (NTCP). Methods: Between July 2014 and September 2015 the first 10 consecutive low or intermediate risk prostate cancer patients were treated with proton therapy at our institution. All 10 patients were planned with three-dimensional conformal proton therapy (3D-CPT) using two parallel opposed fields as well as comparison IMRT plans. A rectal balloon filled with water was used in all patients treated. Prescribed dose to the prostate was 79.2 Gy or cobalt Gy equivalent (CBE) for protons. Dose-volume histograms were compared. The Lyman-Kutcher-Burman model (n = 0.09, m = 0.13, and TD50 = 76.9 Gy) was used to generate NTCP estimates for both IMRT and proton plans. Results: At least 95% of the planning target volume received the prescription dose for both proton and IMRT plans. Dose constraints placed on the rectum included volume receiving 65 Gy (V65) less than 17% and V40 less than 35%. The mean dose to the rectum was 24.5 Gy (range, 19.5-30.1 Gy) and 31.7 Gy (range, 23.7-39.4 Gy) for the proton and IMRT plans, respectively. The V65 constraint was unachievable in 3 of the proton plans and 3 of the IMRT plans. The mean V70 and V75 for proton plans was 8.4% and 5.4% compared to 7.5% and 4.8% for the IMRT plans. The mean NTCP for proton treatment plans was 7.72% (range, 2.7-11.7%) and 7.92% (range, 1.7-15.3%) for IMRT (P = 0.45). After median follow-up of 6 months, no grade 2 or higher toxicity has been reported. Conclusions: Utilizing NTCP estimations, proton therapy and IMRT have similar predicted rates of rectal toxicity. Currently, a Phase III randomized clinical trial is underway comparing proton therapy and IMRT with regards to rectal toxicity and quality of life.

Disorders of Sex Development (DSD): Peer Relations and Psychosocial Well-Being

Social and emotional development is shaped by familial and extra-familial experiences especially interactions with peers. Children and adolescents with physical, behavioral or developmental differences, such as youth with disorders of sex development (DSD), may not benefit to the same degree as other children and adolescents from experiences with peers. This paper reviews current thinking about the features and effects of experiences with peers and the potential challenges of peer interactions for children and adolescents with DSD. We review findings from studies of adjustment for individuals with DSD. We finish the paper with a brief outline of a research agenda to promote the understanding of adjustment of individuals with DSD.

Mayer-Rokitansky-Küster-Hauser syndrome: sexuality, psychological effects, and quality of life

Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is a congenital condition in which a genetic female is born with vaginal agenesis and a rudimentary to absent uterus. This condition affects a woman's ability to menstruate, to engage in penile-vaginal intercourse, and to bear children. Much has been published about how best to create a neovagina in women with MRKH, but little has been written about the psychological impact of MRKH and quality of life outcomes for women with the condition. A review of the extant literature published from 1955 to 2007 supports that (1) surgical or non-surgical creation of a neovagina alone does not ensure a successful psychological outcome, (2) psychological support at critical times can be helpful, and (3) how professionals use language to discuss the condition may positively or negatively influence a female's experience of MRKH. This article discusses the implications that existing knowledge has on future research and on clinical practice. Understanding how women with MRKH cope with and adjust to the condition will help healthcare professionals provide optimal care.

Secondary amoebic eye infections in mice due to Acanthamoeba sp

The aim of the present study was to determine the occurrence of eye infections accompanying the infection of the central nervous system and to demonstrate the possible tissue affinity of different strains of amoebae in subsequent infections. The results obtained demonstrate a clear correlation between the occurrence of eye infection and the degree of virulence of the strains. Amoebae isolated from eyeballs and other organs of dead mice did not exhibit any specificity in relation to the organs in subsequent infections. Irrespective of the place of isolation--be it eye or brain--in the subsequent passages, the amoebae were most often found in the brain and lungs, followed only then by the eye of the infected animals.

Extracerebral infections of Acanthamoeba spp. in mice. pathomorphological changes in tissues of infected animals

A variety of Acanthamoeba spp. pathogenic strains were isolated from water pools in the area of Poznań. In many cases amoebae invaded lungs, kidney heart, liver and diaphragm causing significant changes in these Organs. The presence of amoeba outside of CNS was found mainly in the early periods of infection. Amoeba isolated from different organs of dead animals did not exhibit any specificity in relation to the organs in following infections. Infection with both low-and high-virulent strains resulted in pathomorphological changes of similar character. However, changes induced by low-virulent parasites developed later and were less extensive.

Biosynthesis of prostaglandins in pathogenic and nonpathogenic strains of Acanthamoeba spp

The aim of the present study was to examine the biosynthesis of prostaglandins and to investigate factors conditioning their biosynthesis in pathogenic and nonpathogenic strains of Acanthamoeba spp. We established that the activity of the synthase of prostaglandins was almost identical in pathogenic and non-pathogenic strains and that the synthesis of endoperoxide prostaglandins was similar to that of other organisms up to the point at which prostaglandin H2 was produced. The course of biosynthesis in vitro can be activated by various compounds such as glutathione, albumin, and p-chloromercuribenzoic acid (p-CMB), which are either activators or inhibitors of the enzymes. We suggest that the course of biosynthesis of prostaglandins in vivo is most probably activated by tissues or constitutional liquids surrounding the parasites.

The duration of the cyst stage and the viability and virulence of Acanthamoeba isolates

The viability of Acanthamoeba cysts after they have been stored in water at 4 degrees C for a period of 24 years was determined and to estimate their present degree of virulence as compared to its primary values. The viability of 17 amoebae isolates was examined using the eosin exclusion and in vitro excystation on agar plates (NNE). After the period of 24 years, only 3 isolates were found dead. The remaining 14 isolates after inoculation on NNE gave rise to new subcultures, although the percentage of living cysts measured by eosin exclusion was low (0-5%). Separate groups of mice were inoculated intranasally with 10 subcultures characterised by varying primary virulence. It was found that in 8 groups the mice were invaded (at varying degree), and some of them died. Taking into consideration the fact that some of the examined isolates completely lost their virulence only after 8 years of the in vitro cultivation, the obtained results are very intriguing. On the ground of these results one can assume that in the natural environment the period of viability for a cyst may be not shorter than 25 years, and, which is even more essential, they can maintain their invasive properties.

The effect of the passages of Acanthamoeba strains through mice tissues on their virulence and its biochemical markers

The aim of this study was to determine the enzymatic differences in the process of increasing the degree of virulence in attenuated Acanthamoeba strains as well as strains freshly isolated from the natural environment. The data obtained in our studies indicate that by intranasal infection of mice, one can restore virulence in primary virulent strains and make virulent strains that primarily were noninvasive. The levels of peroxidase and proteinase activity measured thoroughly correlated with the increase in the degree of virulence observed during the process of making the amoeba virulent by inoculating them into mice. We observed that in cases in which the activity of peroxidase and proteinase was higher than 0.150 units/mg protein and 8 units/mg protein, respectively, some of the animals infected with the strains showing this activity of peroxidase and proteinase died. In nonvirulent strains as well as in poorly virulent strains, we observed a decidedly lower activity of these enzymes.

[Amebic keratitis-keratitis acanthamoeba]

In seventeen patients who suffered of corneal ulcer, and were negative in bacteriological and mycological examinations, parasitological tests were performed between 1990-1992. Acanthamoeba keratitis was diagnosed in one patient with characteristic corneal changes of right eye following trauma. The patient was not a contact lens wearer. The amoeba found in direct smears of scraping from corneal ulcer and isolated and cloned in in vitro conditions (isolate-clone-No. 2961) belonged to Acanthamoeba polyphaga species. The trophozoites showed a low degree of invasiveness and high virulence when tested in BALB/c mice. The authors discussed the epidemiology of Acanthamoeba keratitis and pointed out to the necessity of accurate laboratory diagnosis and discerning interpretation of the results to prevent an Acanthamoeba-phobia among the potential patients and most of all among the medical staff.

Proteolytic enzymes of pathogenic and non-pathogenic strains of Acanthamoeba spp

The aim of this work was biochemical characterization and classification of proteinases in pathogenic and non-pathogenic strains of Acanthamoeba spp. The authors showed two proteinase (acid 35 kDa and alkaline 65 kDa) which could be separated electrophoretically. Acid proteinase was inhibited by serine proteinase inhibitors such as DIFP. The second enzyme which was active at alkaline pH, was enhanced by EDTA and inhibited by iodoacetate (IAA) and (p-CMB) p-chloromercuribenzoate. These substances are known to inhibit cysteine type proteinases. The alkaline proteinase was more distinctively active in pathogenic strains and belongs to cysteine class (EC 3.4.22), whereas the acid proteinase was similar active in pathogenic and non-pathogenic strains and belong to serine class (EC 3.4.21).

Biochemical markers of pathogenicity and virulence of Acanthamoeba sp. strains

The aim of our study was to demonstrate a possible correlation between some biochemical and biological markers of the degree of virulence of the investigated strains of Acanthamoeba sp. The results obtained demonstrated a significant correlation between the activity of proteases, peroxidases, and superoxide dismutase and the degree of virulence of the strains as previously defined by tests on mice. The results also proved that the strains that killed some of the infected mice were characterized by the highest value recorded for the activity of peroxidase and the lowest value obtained for the activity of superoxide dismutase.

Pubertal disorders. Psychology and clinical management

The behavioral data reviewed herein must be viewed with caution. Although there are reports that adhere to rigorous methodology, these are the exception. Most reports do not adequately describe either the methodology used or their sample. Subjects are often of mixed endocrine diagnoses, and sometimes the results are of both boys and girls. All of these pitfalls make interpretation of results difficult and limiting. With this in mind, the following conclusions are offered. The majority of behavioral data on precocious puberty comes from studies of IPP in girls. Cognitively, IPP has been associated with average to high-average intelligence. Purportedly, the finding of lower visual-spatial skills than verbal skills in early maturing boys and girls has received equivocal support by cognitive studies of IPP individuals. Similarly, clear differences in hemispheric lateralization have not been demonstrated. Aside from increased somatic complaints during the nonmenstrual phases of their menstrual cycle, girls with IPP show a spectrum of behavior adjustments. Major psychopathology is rare. Clearly, their early development makes them look older than their actual age, which probably alters the expectations others have for them. Psychosexually, however, IPP girls develop in concert with their chronologic age and social experience, rather than their early biologic maturation. However, recent reports suggest a modest influence of hormones. In summary, these studies support an interactionist theory of human psychosexual development. Research data on IPP girls suggest that they do not significantly differ from girls who are early maturers but within the normal range. Research on these girls indicates that most negotiate their puberty without severe problems. There has been less research on IPP boys because it occurs so rarely. Most of what is understood about precocious puberty in boys comes from boys with precocious puberty secondary to poorly controlled CAH. Behavioral data on individuals with delayed puberty come almost exclusively from boys. Although CD appears to be the most frequently diagnosed form of delayed puberty and does not reflect a known pathologic process, men with CD as well as those with organic disorders appear to be at risk for psychosocial and psychosexual difficulties. These difficulties are not severe forms of psychopathology. Rather, they probably represent problems negotiating the expected adolescent lessons of psychosocial development with a physique that places them at a disadvantage. They clearly look younger than their actual chronologic age. Cognitively, as with the children with precocious puberty, there is no evidence of intellectual impairment associated with delayed puberty.(ABSTRACT TRUNCATED AT 400 WORDS)

Management of male pseudohermaphroditism: a case report spanning twenty-one years

Management of infants born with ambiguous sex organs requires the close collaboration of a team of professionals: pediatric endocrinologist, pediatric psychologist, gynecologist, and surgeon. The interdisciplinary teamwork of a group of professionals is described in the case of a patient announced at birth as a male but within days reannounced and reared as a female. Over the next 21 years, she became completely aware of her endocrine condition, including its medical classification (male pseudohermaphroditism), her chromosomal (46 XY) and gonadal (testes) status, and her early history of male sex assignment. The clinical management described herein helped this person deal effectively with her condition despite unsuccessful reconstructive vagal surgery. Substantiation of this is provided by the patient's personal comments.

Data on virilization and erotosexual behavior in male hypogonadotropic hypopituitarism during gonadotropin and androgen treatment

The goal of this investigation was to assess whether or not gonadotropin therapy enhanced the degree of virilization and psychosexual behavior of men with hypogonadotropic hypopituitarism. Pre- and post-gonadotropin assessments of virilization in four men indicated that gonadotropin therapy was associated with dramatic improvements in the degree of virilization that each man previously obtained on androgen only. Retrospective interview data on erotosexual behavior indicated improved erotosexual function on gonadotropin as compared to the prior androgen treatment. These data suggest that complete virilization in these men was partially gonadotropin dependent. Whether or not the behavioral benefits reported by these men represented a direct or synergistic effect of gonadotropin in the expression of erotosexual behavior or an indirect effect of improved virilization can not be answered by these data.

Micropenis. III. Primary hypogonadism, partial androgen insensitivity syndrome, and idiopathic disorders

This paper, the third in a series, presents data from 28 patients with micropenis categorized as primary hypogonadism (11 subjects), partial androgen insensitivity (1 subject), idiopathic (6 subjects), and etiology undetermined (10 subjects). Among the 11 patients with primary hypogonadism, 8 presented with various degrees of gonadal dysgenesis, 1 was a true hermaphrodite and 2 had the Robinow syndrome. Nine of the 28 patients were raised as females: 5 with primary hypogonadism and 4 with undetermined etiology. Eleven of the 19 patients raised as males received androgen stimulation during prepubertal years and responded with penile growth. However, this growth response was temporary and did not appear to be predictive of eventual adult size of the penis. Generally, the prestimulation size of this group of patients is more predictive of adult penile size. Only 7 of the patients raised as males have attained adult somatic growth. Three out of the three with primary hypogonadism, the subject with partial androgen insensitivity, and one of three with idiopathic micropenis have below-normal adult penile length. These limited data suggest that growth potential of the micropenis may be greater among the patients with an idiopathic state than among those with primary hypogonadism and partial androgen insensitivity.

Micropenis. II. Hypogonadotropic hypogonadism

This paper documents the case histories of 14 patients with hypogonadotropic hypogonadism and micropenis (penile length below 2.5 SD from the mean for the patient's chronlogical age, or for age corresponding to stage of sexual development). Nine of the patients were raised as males. Five of them received androgen for the purpose of stimulating penile growth: two realized normal adult penile length (-0.2 and -2.1 SD from normal mean length) whereas the other three had penile lengths significantly below the mean (-3.6, -4.6 and -5.2 SD from normal mean length). These data suggest that among hypogonadotropic patients with micropenis, those with prepubertal penile lengths between 2.5 and 3 SD below the mean may develop an adult penis of a length within the normal range. However, for those presenting with a shorter phallus, the expectation is that penile length will remain greater than 2 SD below the mean.