Differential Mueller matrix imaging of partially depolarizing optically anisotropic biological tissues.

Since recently, a number of innovative polarization-based optical imaging modalities have been introduced and extensively used in various biomedical applications, with an ultimate aim to attain the practical tool for the optical biopsy and functional characterization of biological tissues. The techniques utilize polarization properties of light and Mueller matrix mapping of microscopic images of histological sections of biological tissues or polycrystalline films of biological fluids. The main drawback of currently developed laser polarimetry approaches and Mueller matrix mapping techniques is poor reproducibility of experimental data. This is due to azimuthal dependence of polarization and ellipticity values of most matrix elements to sample orientation in respect to incidence light polarization. Current study aims to generalize the methods of laser polarimetry for diagnosis of partially depolarizing optically anisotropic biological tissues. A method of differential Mueller matrix mapping for reconstruction of linear and circular birefringence and dichroism parameter distributions of partially depolarizing layers of biological tissues of different morphological structure is introduced and practically implemented. The coordinate distributions of the value of the first-order differential matrix elements of histological sections of brain tissue with spatially structured, optically anisotropic fibrillar network, as well as of parenchymatous tissue of the rectum wall with an "islet" polycrystalline structure are determined. Within the statistical analysis of polarization reproduced distributions of the averaged parameters of phase and amplitude anisotropy, the significant sensitivity of the statistical moments of the third and fourth orders to changes in the polycrystalline structure of partially depolarizing layers of biological tissue is observed. The differentiation of female reproductive sphere connective tissue is realized with excellent accuracy. The differential Mueller matrix mapping method for reconstruction of distributions of linear and circular birefringence and dichroism parameters of partially depolarizing layers of biological tissues of different morphological structures is proposed and substantiated. Differential diagnostics of changes in the phase (good balanced accuracy) and amplitude (excellent balanced accuracy) of the anisotropy of the partially depolarizing layers of the vagina wall tissue with prolapse of the genitals is realized. The maximum diagnostic efficiency of the first-order differential matrix method was demonstrated in comparison with the traditional methods of polarization and Mueller matrix mapping of histological sections of light-scattering biological tissues.

Polarization-phase images of liquor polycrystalline films in determining time of death.

An optical model for generalized optical anisotropy of polycrystalline networks of albumin and globulin liquor of the human brain has been suggested. The polarization-phase method for spatial and frequency differentiation of linear and circular birefringence coordinate distributions has been analytically substantiated. A set of criteria documenting the dynamics of polarization-phase images of liquor polycrystalline films has been identified in determining time of death.

Additional approaches to solving the phase problem in optics.

The paper presents principal approaches to diagnosing the structure-forming skeleton of a complex optical field. Analysis of optical field singularity algorithms, depending on intensity discretization and image resolution, has been carried out. An optimal approach is chosen, which allows us to get much closer to the solution of the phase problem of localization speckle-field special points. The use of a "window" 2D Hilbert transform for reconstruction of the phase distribution of the intensity of a speckle field is proposed. It is shown that the advantage of this approach consists in the invariance of a phase map to a position change of the kernel of transformation and in a possibility to reconstruct the structure-forming elements of the skeleton of an optical field, including singular points and saddle points. We demonstrate the possibility to reconstruct the equi-phase lines within a narrow confidence interval and introduce an additional algorithm for solving the phase problem for random 2D intensity distributions.

Cement hydration investigation by method of piezoelectric photoacoustics.

The piezoelectric photoacoustics application possibility for polycrystalline structure formation has been considered. The accent was on research and transient modeling with pulse laser irradiation. A mathematical model for the given setup with a single laser impulse was developed. The results of mathematical modeling were experimentally tested on cement samples.

Optical correlation algorithm for reconstructing phase skeleton of complex optical fields for solving the phase problem.

We propose an optical correlation algorithm illustrating a new general method for reconstructing the phase skeleton of complex optical fields from the measured two-dimensional intensity distribution. The core of the algorithm consists in locating the saddle points of the intensity distribution and connecting such points into nets by the lines of intensity gradient that are closely associated with the equi-phase lines of the field. This algorithm provides a new partial solution to the inverse problem in optics commonly referred to as the phase problem.

Laser-radiation scattering by cement in the process of hydration: simulation of the dynamics and experiment.

This paper discusses simulation of speckle-field dynamics during coherent light scattering by a cement surface in the process of hydration. Cement particles are represented by the spheres whose sizes and reflection indices are changing during the hydration process. The study of intensity fluctuations of scattered coherent radiation is a suitable technique for the analysis of both fast and slow processes of mineral binder hydration and formation of polycrystalline structures in the process of hardening. The results of simulation are in good agreement with the experimental data.

Investigation of optical currents in coherent and partially coherent vector fields.

We present the computer simulation results of the spatial distribution of the Poynting vector and illustrate motion of micro and nanoparticles in spatially inhomogeneously polarized fields. The influence of phase relations and the degree of mutual coherence of superimposing waves in the arrangements of two-wave and four-wave superposition on the characteristics of the microparticle's motion has been analyzed. The prospects of studying temporal coherence using the proposed approach are made. For the first time, the possibility of diagnostics of optical currents in liquids caused by polarization characteristics of an optical field alone, using nanoscale metallic particles has been shown experimentally.

Cheilitis glandularis: clinico-histopathological diagnostic criteria.

OBJECTIVES: To present a combination of clinical and histopathological criteria for diagnosing cheilitis glandularis (CG), and to evaluate the association between CG and squamous cell carcinoma (SCC). MATERIALS AND METHODS: The medical literature in English was searched from 1950 to 2010 and selected demographic data, and clinical and histopathological features of CG were retrieved and analysed. RESULTS: A total of 77 cases have been published and four new cases were added to the collective data. The clinical criteria applied included the coexistence of multiple lesions and mucoid/purulent discharge, while the histopathological criteria included two or more of the following findings: sialectasia, chronic inflammation, mucous/oncocytic metaplasia and mucin in ducts. Only 47 (58.0%) cases involving patients with a mean age of 48.5 ± 20.3 years and a male-to-female ratio of 2.9:1 fulfilled the criteria. The lower lip alone was most commonly affected (70.2%). CG was associated with SCC in only three cases (3.5%) for which there was a clear aetiological factor for the malignancy. CONCLUSIONS: The proposed diagnostic criteria can assist in delineating true CG from a variety of lesions with a comparable clinical/histopathological presentation. CG in association with premalignant/malignant epithelial changes of the lower lip may represent secondary, reactive changes of the salivary glands.

On polarization metrology (estimation) of the degree of coherence of optical waves.

A new approach is proposed for estimating the degree of coherence of optical waves. The possibility of transformation of the spatial polarization distribution in the measured spatial intensity distribution for determining the degree of correlation of superposing waves, linearly polarized in the plane of incidence, is shown.

Association between season and temperature and unstimulated parotid and submandibular/sublingual secretion rates.

OBJECTIVE: The purpose of the present study was to evaluate parotid and submandibular/sublingual (SM/SL) unstimulated salivary secretion rate in a group of healthy individuals in winter and summer, and to observe the effect of room-adjusted temperature (air-conditioning) on salivary flow-rate in those seasons. DESIGN: Unstimulated salivary secretion rates of the right parotid and the SM/SL glands were measured in 50 healthy Israeli volunteers. Each volunteer was evaluated four times during the study: twice in winter (February-March) and twice in summer (July-August). RESULTS: Parotid and SM/SL salivary mean secretion rate in winter was significantly higher than in summer (p<0.02 and p<0.05, respectively). Room heating in winter lowered significantly the mean parotid flow. Air-conditioning cancelled almost completely the seasonal effects on parotid and SM/SL secretions. CONCLUSIONS: The results of this study suggest that room temperature is an important factor in measurement of salivary secretion rate. Hence, temperature should ideally be recorded and reported when assessing salivary flow-rates.

[Evaluation of unstimulated and stimulated parotid salivary flow rate in Israeli healthy subjects aged 60 years and older].

Saliva plays a critical role in the maintenance oral health. Clinical studies showed that 25% of the elderly population suffers from oral dryness and its related complaints. Studies that measured parotid gland salivary flow rate, both unstimulated and stimulated, in healthy older individuals did not find age-related functional changes. However, histological studies have revealed an age-dependent reduction in the parotid acinar tissue component. To our knowledge there are still no reports of the parotid salivary flow rate in the elderly population in Israel. The goal of this study was to evaluate the rate of the parotid unstimulated and stimulated salivary flow rate among healthy Israeli people aged over 60 years old--the findings may serve as basic standard values to be compared to data collected from patients with complaints of xerostomia and to data reported in other studies. Thirty healthy volunteers aged 60 to 77 years (average 64.7), 23 females and 7 males, were evaluated. Twenty five of the subjects used to live in kibbutzim and 5 lived in a city. The mean unstimulated parotid salivary secretion rate was 0.044+/-0.063 ml/min and the mean stimulated secretion was 0.163+/-0.291 ml/min. Those rates were found to be lower than the unstimulated and stimulated parotid salivary flow rates reported in most other studies. Fourteen (43.3) of the subjects had zero flow rate at rest. This figure was higher then the 20% zero flow at rest that was reported by others among persons with a broader age range. No significant differences were recorded in the parotid salivary flow, both unstimulated and stimulated, between subjects living in the kibbutzim compared to those living in the city. Similar to other studies the differences in the secretion rates between men and women were non significant. The low mean unstimulated and stimulated salivary flow rates, and the high prevalence of no flow at rest can be explained by the fact that saliva collections were done during the very warm Israeli summer and it is speculated that the subjects might be dehydrated. General dehydration can be observed in warm climate areas. No significant differences were found in the parotid salivary flow rates, (unstimulated and stimulated), between the city subjects compared to those from the kibbutzim. Further similar studies in different weather conditions (winter-summer) are needed to establish data of the normal parotid salivary secretion in the over 60 years old Israeli population.

Collection of autologous PBSC in patients with polycythemia vera.

BACKGROUND: Allogeneic stem-cell transplantation (SCT) can eradicate myelofibrosis (MF), but is limited by donor availability and toxicity. We previously reported normalization of counts and resolution of MF after ablative, syngeneic SCT in spent phase polycythemia vera (PV). Hence, GvL is not required to eradicate MF. Autologous SCT may advance treatment for spent phase PV by restoring effective hematopoiesis. The influence of organomegaly, myelosuppression and MF on PBSC collection has not been studied in the setting of PV. METHODS: Sixteen patients with PV underwent PBSC collection. Mobilization was with filgrastim alone, with a target cell content of 2.5 x 10(6) CD34(+)/kg. All myelosuppression was discontinued 2 weeks prior to collection. RESULTS: Median ages at diagnosis and collection were 47 and 57 years, respectively. Organomegaly, MF and use of myelosuppressive therapies were present in 10 (63%), 4 (25%) and 7 (44%) patients. Median total nucleated cells (TNC) and CD34(+) counts were 8.3 x 10(8)/kg and 4.98 x 10(8)/kg. MF had an adverse effect on TNC (p=0.05) but not on the CD34(+) content. Time from diagnosis and the use of myelosuppresion had no influence on TNC and CD34(+) contents. Four patients had CD34(+) contents <2.5 x 10(6)/kg. Complete blood count (CBC) parameters were not predictive of CD34(+) content. DISCUSSION: Autologous PBSC collection is feasible in PV several years after diagnosis. Organomegaly and MF are not absolute contraindications for collection. Discontinuing myelosuppresion for 2 weeks before mobilization appears sufficient to collect adequate numbers of CD34(+) progenitors.

Characteristics of oral and paraoral malignant lymphoma: a population-based review of 361 cases.

BACKGROUND: Lymphoma is the second most common neoplasm of the head and neck; almost 50% of all lymphomas occur in this region. Waldeyer's ring is the most common site of lymphomas involving the oral region. The purpose of this study was to review the characteristics of a large series of malignant lymphoma of the oral region. METHODS: Three hundred sixty-one consecutive cases of malignant lymphoma of the oral region were identified in the Tumor Registry between 1969 and 1998. RESULTS: The 361 cases (200 males and 161 females) of malignant lymphoma of the oral region accounted for 3.5% of all oral malignancies. The mean age was 62.5 years and the most prevalent site of involvement was the tonsil (32.7%), followed by the parotid gland (16.1%). Sixty-five percent of the lesions were diagnosed as large-cell (38%) or small-cell (27%) lymphoma. One quarter of the patients died of the disease in a mean of 2.78 years after diagnosis. Of a total 26 patients who died from other causes, 12 died because of other cancers, including 7 (27%) with leukemia and 5 (19%) with oral carcinoma. The prognosis is based, at least partially, on the histologic grading (low, intermediate, or high) and the anatomic stage of the disease. Localized low-grade lymphomas have a more favorable prognosis compared with those that are disseminated and/or have high-grade cellular changes. CONCLUSION: Lymphoma is the second most common malignant oral disease. Thorough head and neck and oral examination is necessary to identify lesions that may represent lymphoma.

Topical azathioprine in the treatment of immune-mediated chronic oral inflammatory conditions: a series of cases.

OBJECTIVES: After hematopoietic cell transplantation, a variety of complications can occur, including chronic graft-versus-host disease (GVHD), with 25% to 70% of these involving the oral cavity. Those lesions, as well as oral involvement of autoimmune mucocutaneous diseases, might present as painful, erythematous, and ulcerative oral lesions. Management includes topical and systemic immunosuppressive agents, including systemic azathioprine (AZA). The purpose of this study was to evaluate the efficacy of topical AZA in chronic oral GVHD and in oral autoimmune diseases in a series of patients. METHODS: Four men and 2 women with GVHD and 2 men with autoimmune vesiculo-ulcerative oral lesions were treated with topical AZA. A rinse of 5 mL of 5 mg/mL AZA in methylcellulose were rinsed 3 to 4 times daily for over 1 minute and expectorated, or a gel in the same concentration in 3% methylcellulose was topically applied. The outcome was evaluated separately for total ulcer size, assessment of the erythema, and severity of pain by using a visual analogue scale. Global estimated improvements represented a proportional combined improvement of ulcers, erythema, and pain. RESULTS AND CONCLUSIONS: The mean estimated global improvement for 6 patients with GVHD who used AZA rinse was 60% in a mean of 16.67 weeks. Ulcers improved by 58%, erythema by 55%, and pain was reduced by 63%. Two patients with oral lesions of vesiculo-ulcerative diseases (1 AZA rinse and 1 topical gel) improved by 95% and 96%, respectively, in 3 months. One patient with GVHD applied topical AZA gel in addition to mouthrinses, and a 29% estimated global improvement was achieved in addition to 50% of improvement achieved with AZA mouthrinses. The observed effect of topical AZA suggests that it can be used for management of oral immune-mediated inflammatory conditions, and for patients who are provided with systemic immunosuppressives it can allow control of oral findings with lower systemic dosing. The therapeutic potential of topical AZA as mouthrinse versus topical applications and the most effective concentration should be further investigated.

A case series of acquired immunodeficiency syndrome patients with initial neoplastic diagnoses of intraoral Kaposi's sarcoma.

BACKGROUND: Oral Kaposi's sarcoma (KS) may represent the initial clinical manifestation of immunosuppression in human immunodeficiency virus disease. This article reviews the treatment provided to these patients and the outcome of the disease and provides the opportunity to assess the impact of improvements in the medical therapy of acquired immunodeficiency syndrome on disease outcome. METHODS: A tumor registry was examined to identify patients in whom oral KS was the first neoplastic diagnosis. RESULTS AND CONCLUSIONS: Thirty-seven cases of oral KS representing 1.9% of all cases of KS were identified as the first malignant diagnosis in patients with acquired immunodeficiency syndrome. Patients with oral KS have limited survival; the cause of death is either infection or malignancy. In our study, the palate was the most common site of primary involvement in the oral cavity. Recently diagnosed patients remained alive longer than those diagnosed earlier, and the patients with the most recently diagnosed cases were alive at the completion of the study, suggesting that medical management of human immunodeficiency virus has improved with new therapies.

Craniofacial osseous and chondromatous sarcomas in British Columbia--a review of 34 cases.

Head and neck sarcomas are very rare diseases. The aim of this study was to assess the prevalence and presentation of hard tissue sarcomas in the head and neck and jaws. A search of the British Columbia Tumor Registry identified 34 craniofacial hard tissue sarcomas (11 chondrosarcomas, 23 osteosarcomas) over a period of 29 years. A male predominance (1.8:1) and a mean age of 40.4 years at diagnosis were seen. Of the 23 patients with osteosarcoma, one-third survived for 5 years and 12 (52%) died within a mean of 20 months. Of the 11 patients with chondrosarcoma, 45% survived for 5 years and two (18%) of the patients died within a mean of 6 months. In nine of the osteosarcoma patients (39%) the jaws were involved, and in six of those cases (67%) there was mandibular involvement. Swelling was the first sign in all jaw patients, with a mean age of 41.1 years at diagnosis and a male predominance with a ratio of 8:1. Three of the eight male patients with osteosarcoma of the jaw (38%) died within a mean of less than 1 year. Improved prognosis is related to early recognition and diagnosis to allow for adequate surgical resection. The benefit of a combination of surgery with irradiation or chemotherapy continues to be investigated.

The correlation between epidermal growth factor levels in saliva and the severity of oral mucositis during oropharyngeal radiation therapy.

BACKGROUND: Epidermal growth factor (EGF) is present in biologic fluids, including saliva, and plays a role in maintenance of the epithelial barrier and in healing of damaged mucosa. The purpose of this study was to assess the relation between salivary EGF and the severity of oral mucositis in patients with carcinoma of the head and neck during radiation therapy. METHODS: Whole resting saliva (WRS) and whole stimulated saliva (WSS) were collected prior to radiation and each week during radiation treatment for 11 men and 7 women. Oral mucositis was evaluated using the National Cancer Institute (NCI) scale of 0-4 and the Oral Mucositis Assessment Scale (OMAS), which evaluates the extent of erythema (scale of 0-2) and ulcerations (scale of 0-3) in nine oral sites. The overall OMAS score of 0-45 reflected the mucosal condition. EGF was assayed in the saliva specimens. RESULTS: The total mean radiation dose delivered to the head and neck was 5667 centigrays (cGy) in a mean of 24 fractions. Ulcerative oral mucositis occurred in 94% of patients. The mean OMAS score ranged from 2.83 in the first week of treatment to 14.77 in the fifth week. The mean WRS and WSS volumes decreased significantly from pretreatment to the first week of radiation treatment and then remained stable. A similar pattern was seen for the mean total output of EGF. A significant and negative correlation was found between higher levels of EGF in stimulated saliva and low OMAS score, reflecting less severe erythema and ulceration. A general trend showing that less tissue damage was associated with a higher EGF level in resting saliva also was illustrated. EGF levels were correlated with the OMAS score; however, no correlation was found when assessing the NCI score, which combines tissue damage with function and symptoms in a single score. CONCLUSIONS: Radiation-induced mucositis appeared to be modified by saliva volume, total EGF, and concentration of EGF in the oral environment. Saliva volume and total EGF output decreased significantly in the first weeks of treatment and remained reduced throughout radiation therapy. The findings suggest that higher levels of EGF in saliva, particularly in stimulated saliva, prior to and during radiation treatment may be associated with less severe mucosal damage due to radiation therapy. It is also postulated that human EGF may affect the development and healing of radiation-damaged mucosa.

Topical application of vitamin A to oral leukoplakia: A clinical case series.

BACKGROUND: Due to the possibility of malignant transformation of oral leukoplakia, these lesions must be assessed and managed closely and, if not resolved, must be reassessed on a regular basis. METHODS: This study evaluated the use of topical 0.05% vitamin A (tretinoin) acid gel for the treatment of oral leukoplakia. Tretinoin was applied topically 4 times a day for the management of nonmalignant oral white lesions in 26 patients. The clinical response was evaluated in all patients and posttreatment biopsies were performed in ten patients. RESULTS: The mean age of the patients at the time of diagnosis was 62 years. Of the 26 patients, 50% were tobacco users. Patients were followed for a mean of 23 months. Approximately 27% of the patients had a complete clinical remission. Recurrence of leukoplakia was observed in approximately 40% of patients in whom complete clinical remission occurred if topical applications were discontinued. A 50% reduction in the clinical grade of leukoplakia from a mean of 2.8 to 1.4 on a scale ranging from 0 (no leukoplakia) to 4 (speckled leukoplakia) was observed. When the pretreatment and posttreatment biopsies from 10 patients were evaluated, no change in the mean histologic grade (between mild and moderate dysplasia) was noted; however, some reduction in the histologic grade was noted in 3 of these patients (30%). CONCLUSIONS: The use of topical vitamin A acid showed a limited effect in controlling oral leukoplakia. Further studies are needed to establish the appropriate indication, efficacy, and best choice for chemoprevention agents. Close follow-up of all patients with oral leukoplakia is required.