Comparison of Percent Tissue altered in Topography Guided and Wavefront Optimized Laser-assisted in situ Keratomileusis using Zeiss MEL 80 Excimer Laser

Introduction: Laser-assisted in situ Keratomileusis (LASIK) is the most commonly performed refractive surgical procedure. The amount of tissue ablated in LASIK affects the safety and long-term outcome. The objective of this study was to compare the percent tissue altered (PTA) in topography guided (TG) and wavefront optimized (WFO) LASIK using Zeiss MEL 80 excimer laser. Materials and methods: This retrospective observational study was conducted at a tertiary eye center. Patients with moderate myopia who underwent LASIK between June 2016 and January 2019 were divided into two groups (Group I: TG LASIK, 69 eyes; Group II: WFO LASIK, 70 eyes). The groups were compared for preoperative parameters [spherical equivalent (SE), keratometry and pachymetry], intraoperative parameters [ablation depth (AD), PTA and residual stromal bed thickness (RSBT)] and postoperative parameters (vision, SE). Results: Among preoperative parameters, SE and keratometry were similar while thinnest pachymetry was significantly less in group I. Among the intraoperative parameters, PTA (P < 0.01) and AD (P < 0.01) were significantly less in group I while RSBT (P = 0.54) was not significantly different. Postoperatively at 6 months, 92.75% (64) eyes in group I and 90% (63) eyes in group II had visual acuity of 6/6 or better (P = 0.57). 98.55% (68) and 97.14% (68) eyes in group I and group II respectively had SE refraction within ± 0.5 dioptres. Conclusion: TG LASIK induces less tissue alteration for given refractive error with similar visual outcome as compared to WFO LASIK which makes TG apparently safer and is the preferred technique for borderline thin corneas.

Fracture of upper incisors: a three-year follow-up of a multidisciplinary approach

ABSTRACT Multiple clinical specialties are usually needed for a successful long-term treatment in buccal cavity. The aim of this article is to report a clinical case of multi-disciplinary rehabilitation of fracture upper incisors without pulp exposure, concerning about endodontics, periodontics and restorative dentistry comments or procedures. A case of a patient reporting trauma that resulted in fracture and substantial loss of hard tissue, in mesial angle of both upper central incisors (11 and 21). In palatal side, fracture extended beyond cingulum up to subgingival region. Periodontal surgery was performed in order to reestablish biological space. Clinical and radiographic assessments demonstrated no need for endodontic treatment, since pulp was vital and non-altered. Preparations for restorative procedures were minimally invasive, followed by composite direct. A three-year follow-up was performed, consisting in re-assessment of clinical and radiographic aspects, re-polishing of the restorations and photographic documentation. No pulp tissue alteration was observed after the follow-up period. Restorative procedures, adjacent tissues and pulp vitality were considered adequate, and the patient was satisfied with the treatment.

Fossil microbial shark tooth decay documents in situ metabolism of enameloid proteins as nutrition source in deep water environments

Alteration of organic remains during the transition from the bio- to lithosphere is affected strongly by biotic processes of microbes influencing the potential of dead matter to become fossilized or vanish ultimately. If fossilized, bones, cartilage, and tooth dentine often display traces of bioerosion caused by destructive microbes. The causal agents, however, usually remain ambiguous. Here we present a new type of tissue alteration in fossil deep-sea shark teeth with in situ preservation of the responsible organisms embedded in a delicate filmy substance identified as extrapolymeric matter. The invading microorganisms are arranged in nest- or chain-like patterns between fluorapatite bundles of the superficial enameloid. Chemical analysis of the bacteriomorph structures indicates replacement by a phyllosilicate, which enabled in situ preservation. Our results imply that bacteria invaded the hypermineralized tissue for harvesting intra-crystalline bound organic matter, which provided nutrient supply in a nutrient depleted deep-marine environment they inhabited. We document here for the first time in situ bacteria preservation in tooth enameloid, one of the hardest mineralized tissues developed by animals. This unambiguously verifies that microbes also colonize highly mineralized dental capping tissues with only minor organic content when nutrients are scarce as in deep-marine environments.

Abstract 16636: Cardiac Microstructural Associations With Metabolic Syndrome Differ by Sex

Background: Alterations in the orientation and integrity of myocardial fibers can be assessed using ultrasonic image analysis. The ability to detect such microstructural abnormalities may shed light on sex differences in the progression from metabolic risk factors to overt cardiac disease. Methods: In a community-based cohort of N=2510 adults (age 66±9 years, 56% women) without overt cardiovascular disease, we evaluated whether a novel echocardiography-based assessment of left ventricular myocardial microstructure, the signal intensity coefficient (SIC), could detect tissue-level alterations that are associated with metabolic risk factors, such as body mass index (BMI) and the metabolic syndrome. Results: In multivariable models adjusting for age and BMI, women had a significantly greater degree of cardiac microstructural alteration (coeff 0.15; s.e. 0.06, P=0.007) in the presence of metabolic syndrome, whereas this association was only borderline significant in men (coeff 0.11; s.e. 0.06, P=0.07) ( Figure ). Notably, there was no sex-specificity in the associations of either age or BMI with cardiac microstructure. Conclusion: A novel index of myocardial tissue alteration is significantly associated with presence of metabolic syndrome, even after adjusting for body size, and more prominently in women than in men. Further research is needed to examine the extent to which cardiac microstructural abnormalities may mediate the metabolic risks for cardiac disease, particularly in women.

Intra-peritoneal versus retropubic implantation of three-piece inflatable penile prosthesis: Patient-reported outcomes and complications

Introduction: The role of reservoir position was investigated in this series of patients treated with three-pieces penile prosthesis implantation (PPI). The outcomes and the patients’ reported quality of life after insertion of the balloon in the retropubic space, or the Retzius’s space (SOR), were compared with the outcomes of patients who received an intraperitoneal implantation (IP). The study aimed to analyze how the anatomy of the SOR influenced the long-term results of PPI, especially in patients who have been previously exposed to pelvic surgery or radiotherapy. The SOR has usually been identified as ideal for concealing and protecting the reservoir; nevertheless, an increasing rate of patients that ask for a PPI do not conserve the typical favorable characteristic of the SOR. In these cases, the tissue alteration can cause a higher rate of undesired events and can impair the satisfaction from device use. In the recent literature, few articles focus on the topic of reservoir position and very poor information is available about the results of the IP insertion. Materials: Our cohort of patients was retrospectively inspected; the two different subgroups, according to the reservoir position (SOR or IP) were evaluated considering the pre-operative condition, the post-operative complication, the development of undesired events or uncomfortable sensations during the follow-up. The quality of life after PPI was observed as well, with a questionnaire specifically developed for patients treated with PPI. The surgical technique adopted for the intraperitoneal implantation was described. Results: The results of penile prosthesis functionality and patients’ and partners’ reported quality of life (QoL) showed similar results between the two groups but greater satisfaction in the relational domain of the questionnaires adopted was described in the IP subgroup. Conclusion: According to our observations, the IP reservoir insertion guarantees good functionality and lower rates of undesired events after PPI.

Rare case: enucleation of multiple fibroids after intraoperative vaginal sonographic detection of the solitary pelvic kidney by patient with Mayer-Rokitansky-Kuster-Hauser syndrome

Mayer-Rokitansky-Kuster-Hauser syndrome (MRKH) is a congenital anomaly of the genital tract that occurs in about 1 in 4000 women. MRKH syndrome can be associated with renal, skeletal, heart and hearing abnormalities. The frequency of renal/urinary tract abnormalities is 33%. Only a few cases of fibroid development in MRKH syndrome have been described in the literature. The diagnosis and surgery of a fibroid in MRKH syndrome may be complicated in associated kidney abnormality by an atypical kidney position, as in this case: pelvic kidney on one side and renal agenesia on the contralateral side. Authors present the case of a 47-year-old female patient with a known MRKH syndrome and a pelvic kidney on the right side who had presented with an unclear tumour in the right lower abdomen. A completed CT scan revealed the tumour directly next to the pelvic kidney. A malignancy could not be excluded with certainty, so that a laparoscopy in laparotomy readiness was indicated and performed. During surgery, two rudimentary uterine horns were found; on the right side retroperitoneally, below the uterine horn, the tumour was located and directly below it there was a soft tissue alteration, probably the kidney. For safety, a vaginal sonography was performed in between, to clearly identify the only kidney and to avoid damaging it. The tumour could be extirpated laparoscopically without kidney injury. The two uterine horns were removed simultaneously. Histologically the fibroid could be confirmed. In addition, three other fibroids (one on the left side and two on the right side) were detected. Due to the high probability of a simultaneous kidney abnormality in the MRKH syndrome, authors suggest an accurate kidney diagnosis preoperatively. If necessary, in the case of a pelvic kidney and/or renal agenesia, as in this case, an additional intraoperative kidney check should be performed.

Mitigating the Consequences of Subconcussive Head Injuries

Subconcussive head injury represents a pathophysiology that spans the expertise of both clinical neurology and biomechanical engineering. From both viewpoints, the terms injury and damage, presented without qualifiers, are synonymously taken to mean a tissue alteration that may be recoverable. For clinicians, concussion is evolving from a purely clinical diagnosis to one that requires objective measurement, to be achieved by biomedical engineers. Subconcussive injury is defined as subclinical pathophysiology in which underlying cellular- or tissue-level damage (here, to the brain) is not severe enough to present readily observable symptoms. Our concern is not whether an individual has a (clinically diagnosed) concussion, but rather, how much accumulative damage an individual can tolerate before they will experience long-term deficit(s) in neurological health. This concern leads us to look for the history of damage-inducing events, while evaluating multiple approaches for avoiding injury through reduction or prevention of the associated mechanically induced damage.

In Vivo Dielectric Properties of Healthy and Benign Rat Mammary Tissues from 500 MHz to 18 GHz

This work investigates the in vivo dielectric properties of healthy and benign rat mammary tissues in an attempt to expand the dielectric property knowledge of animal models. The outcomes of this study can enable testing of microwave medical technologies on animal models and interpretation of tissue alteration-dependent in vivo dielectric properties of mammary tissues. Towards this end, in vivo dielectric properties of healthy rat mammary tissues and chemically induced benign rat mammary tumors including low-grade adenosis, sclerosing adenosis, and adenosis were collected with open-ended coaxial probes from 500 MHz to 18 GHz. The in vivo measurements revealed that the dielectric properties of benign rat mammary tumors are higher than the healthy rat mammary tissues by 9.3% to 35.5% and 19.6% to 48.7% for relative permittivity and conductivity, respectively. Furthermore, to our surprise, we found that the grade of the benign tissue affects the dielectric properties for this study. Finally, a comparison with ex vivo healthy human mammary tissue dielectric properties revealed that the healthy rat mammary tissues best replicate the dielectric properties of healthy medium density human samples.