Osteoma of the base of the tongue

A 14-year-old girl developed a firm mass at the base of the tongue. Computed tomography indicated marked density suggesting either a foreign body or bony tissue. A thyroid scan confirmed the presence of a normally sized and positioned gland. The mass was removed in toto and found to be an osteoma. This is the first report of a case in which the diagnosis of this rare developmental lesion of the tongue was achieved preoperatively based on clinical and radiologic information. This experience should lead to greater awareness of this entity in the future. Recognition of this entity in the pediatric age group is especially useful in avoiding misdiagnosis of other, potentially more aggressive types of tongue mass lesions. Our case demonstrates that it is possible to detect this entity using computed tomography. The dense calcification is truly characteristic of the tumor and may be relied upon to exclude alternative soft tissue mass lesions. While other forms of osseous and cartilagenous neoplasms, such as extraskeletal osteosarcoma and chondrosarcoma, have been reported arising in the tongue, their malignant nature should otherwise be readily apparent. Osteoma of the tongue is the favored diagnosis when mature bone tissue is imaged at the base of the tongue.     

Three-dimensional ultrasound imaging of the vasculature

With conventional ultrasonography, the diagnostician must view a series of two-dimensional images in order to form a mental impression of the three-dimensional anatomy, an efficient and time consuming practice prone to operator variability, which may cause variable or even incorrect diagnoses. Also, a conventional two-dimensional ultrasound image represents a thin slice of the patients anatomy at a single location and orientation, which is difficult to reproduce at a later time. These factors make conventional ultrasonography non-optimal for prospective or follow-up studies. Our efforts have focused on overcoming these deficiencies by developing three-dimensional ultrasound imaging techniques that are capable of acquiring B-mode, colour Doppler and power Doppler images of the vasculature, by using a conventional ultrasound system to acquire a series of two-dimensional images and then mathematically reconstructing them into a single three-dimensional image, which may then be viewed interactively on an inexpensive desktop computer. We report here on two approaches: (1) free-hand scanning, in which a magnetic positioning device is attached to the ultrasound transducer to record the position and orientation of each two-dimensional image needed for the three-dimensional image reconstruction; and (2) mechanical scanning, in which a motor-driven assembly is used to translate the transducer linearly across the neck, yielding a set of uniformly-spaced parallel two-dimensional images.     

超声成像系统的动态孔径控制方法

动态孔径控制技术是超声成像系统的一个重要环节,良好的动态孔径控制技术能够有效地改善图像质量.在深入分析超声信号的合成波束分布规律的基础上,提出一种能够消除聚焦波束扫描死区的动态孔径控制方法.该方法根据探头阵元数对探测区域进行均匀的区域分割,计算得到完全覆盖相邻两条扫描线之间区域的聚焦波束在该深度下所需的波束宽度,再根据不同探测深度的波束宽度反推该深度下所需的孔径大小.该方法不受探头参数特性改变,以及探测对象变化的影响,在超声成像系统具有普遍适用性.仿真成像表明:采用该动态孔径控制方法能够有效提高超声图像的整体质量.     

Arteriovenous malformation of the base of tongue: case report and literature review

Arteriovenous malformations of the head and neck pose a challenging therapeutic and reconstructive problem. In this report we describe a rare case of an arteriovenous malformation of the base of tongue. The patient, a young adult female, was treated with embolization followed by surgical resection using a lateral pharyngotomy approach. Reconstruction of the extensive base of tongue defect was accomplished using a radial forearm free flap. Currently, the patient is decannulated, articulates clearly, tolerates a normal diet, and is without recurrence. Our treatment approach is discussed in detail and compared with alternative techniques.     

Differential attenuation imaging for the characterization of high intensity focused ultrasound lesions

High intensity focused ultrasound (HIFU) is an effective technique for creating coagulative necrotic lesions in biological tissue, with a view to treating localized tumors. Although good results have already been obtained, notably in urology, current systems lack a real time monitoring system to check the efficacy of the treatment procedures. This study describes the development and assessment of a noninvasive system for making local measurements of attentuation variations during HIFU treatment procedures. An apparatus (Ablatherm, Edap-Technomed, France), combining a 2.5 MHz therapeutic transducer and a 5.5 MHz twin plane imaging probe (connected to an ultrasound scanner), was used to produce lesions. The rf signals needed to calculate the attenuation were recorded as outputs from the ultrasound scanner, before and after the high intensity firing sequences, which were performed on ten pieces of porcine liver. Each firing sequence involved producing a lesion volume comprising 42 individual lesions. A number of recordings were also made without producing lesions, in order to test the reproducibility of the measurements. The attenuation function was evaluated locally using the centroid and the multinarrowband methods. Initially, changes in the integrated attenuation alpha (mean attenuation in the 4-7 MHz range) and the attenuation slope beta were examined for the lesion volume. beta values did not vary significantly within this range, whereas alpha values varied significantly (in the region of 86% of the initial level) in comparison to measurements performed without forming lesions. The differential attenuation delta alpha (representing local variations in alpha) was subsequently used to generate images revealing the lesion areas. There was a strong similarity between these 'delta alpha images' and the lesion volumes defined by the operator. 'delta alpha images' offer several advantages over existing attenuation imaging techniques. Any problems related to the heterogeneity of the medium are eliminated, since only the change in attenuation is taken into account. Furthermore, there is no need to compensate for diffraction when estimating delta alpha, as the rf signals are captured in exactly the same positions before and after treatment. This technique can be used during in vivo treatment procedures. It can be implemented in real time, since the computational algorithms (based primarily on FFT calculations) are very fast. The technique should provide clinical practitioners with valuable qualitative and quantitative information for use in HIFU ultrasound surgery.     

Combined surgery and postoperative radiotherapy for carcinoma of the base of radiotherapy for carcinoma of the base of tongue: analysis of treatment outcome and prognostic value of margin status

BACKGROUND: Choice of treatment for base of tongue carcinoma is controversial, with options including surgery alone, radiotherapy alone, or multimodality treatment. Given the highly aggressive nature of these tumors, it has been our institutional policy to manage this disease with combined partial glossectomy (with attempt to avoid laryngectomy if possible) with planned postoperative radiotherapy (RT). We reported on our institutional experience with this approach. METHODS: A retrospective review of the charts of 17 patients with primary base of tongue squamous cell carcinoma treated with surgery and postoperative RT was performed. Patients treated with chemotherapy as part of their management were excluded. All patients underwent partial, hemi-, or subtotal glossectomy; 15/17 patients underwent ipsilateral radical or modified radical neck dissection. All patients received comprehensive postoperative RT (median dose 6000 cGy; range 5040-6920 cGy). Stage distribution was as follows: stage I, 2; stage II, 3; stage III, 2; stage IV, 10. Positive margins for invasive carcinoma were found in 9/17 patients. Median follow-up of surviving patients is 46 months; median follow-up for all patients is 31 months. RESULTS: For the entire group of patients, the actuarial 3-year local-regional control rate was 68%. The actuarial 3-year overall survival rate was 46%. The local-regional control rate was 83% for patients with stage I-III disease versus 50% for stage IV disease. There were no local failures among eight patients with negative margins (local control 100%) compared with an actuarial local control rate of 36% among patients with positive margins (p = .03). Survival, disease-specific survival, and locoregional control were also highly correlated with margin status (p = .003). Late major complications included 5/17 patients requiring permanent G-tubes and/or tracheostomy to prevent aspiration. CONCLUSIONS: Surgery plus postoperative RT is an intensive treatment for carcinoma of the base of tongue which offers high locoregional control in patients in whom negative margins are achieved. Positive margins indicate a high risk of locoregional and systemic failure, and these patients should be considered for innovative clinical trials after surgery.     

Limitations for three-dimensional ultrasound imaging through a bore-hole trepanation

It has been studied the correlation of the mitotic activity of the chromosome aberrations and apoptosis, in the V-79 cells pre-exposure to an adapting dose of ionizing radiation from 14C-thymidine prior to an acute challenge dose of gamma-rays. In spite of that the incubation of the cells with isotope increased of the yield of the chromosome aberrations, but the cells became more resistant to following gamma-irradiation. Increasing the adaptive dose of the 14C on degree didn't influence on the present of the adaptive response. However, using concentrations of the 14C damaged metaphase/anaphase transition and cells blocked in this check-point by apoptotic death. The results suggest, that the cellular selection has been involved in 14C-induced adaptive response, estimated by level of asymmetric chromosome aberrations in V-79 cells.     

Comparison of ultrasound imaging in patients undergoing transperineal and transrectal prostate ultrasound

OBJECTIVES: Prostatic evaluation in men who have undergone prior abdominoperineal resection pose an unusual challenge for the urologist. Neither digital rectal examination nor transrectal ultrasound (TRUS) can be performed. Transperineal ultrasound (TPUS) has been suggested as an alternative means of imaging. This imaging modality was compared directly with the standard TRUS method. METHODS: TPUS was performed with a 4-MHz abdominal probe or biplane multiple frequency probe at a frequency of 5 to 7 MHz followed by TRUS at 7 MHz in 50 consecutive men referred for prostate ultrasound and biopsy who had not undergone prior abdominoperineal resection. Dimensions of the prostate and ultrasound findings such as hypoechoic, anechoic, or hyperechoic areas were noted for each sonographic approach. Volume calculation was performed by the prolate spheroid method. RESULTS: There was good TPUS visualization of the prostate in the transverse plane in 48 (96%) of 50 patients and in the sagittal plane in 45 (90%) of 50 patients. Prostate volume calculation by TPUS correlated well with the volume calculated by TRUS (r=0.876). Twenty-nine patients (58%) were found to have suspicious hypoechoic lesions by TRUS; none were seen by TPUS. Prostatic calcifications were present in 12 patients and were visualized by both TPUS and TRUS in all 12 patients. Six prostate glands demonstrated cystic lesions on TRUS imaging; three of these cystic lesions were also seen with TPUS imaging. CONCLUSIONS: TPUS allows visualization of the prostate with volume determination that is comparable to the volume determination by TRUS. Some intraprostatic findings such as calcifications and cysts can be identified; however, suspicious hypoechoic lesions were not identified by TPUS imaging of the prostate.     

Real-time strain rate imaging of the left ventricle by ultrasound

The regional function of the left ventricle can be visualized in real-time using the new strain rate imaging method. Deformation or strain of a tissue segment occurs over time during the cardiac cycle. The rate of this deformation, the strain rate, is equivalent to the velocity gradient, and can be estimated using the tissue Doppler technique. We present the strain rate as color-coded 2-dimensional cine-loops and color M-modes showing the strain rate component along the ultrasound beam axis. We tested the method in 6 healthy subjects and 6 patients with myocardial infarction. In the healthy hearts, a spatially homogeneous distribution of the strain rate was found. In the infarcted hearts, all the infarcted areas in this study showed up as hypokinetic or akinetic, demonstrating that this method may be used for imaging of regional dysfunction. Shortcomings of the method are discussed, as are some possible future applications of the method.     

Development of transplantation vasculopathy and progression of donor-transmitted atherosclerosis: comparison by serial intravascular ultrasound imaging

BACKGROUND: Transplant coronary artery disease is a combination of atherosclerosis transmitted from the donor and new lesions of allograft vasculopathy. We sought to determine the morphological characteristics of allograft vasculopathy and differentiate it from donor-transmitted atherosclerosis with serial intravascular ultrasound. METHODS AND RESULTS: Intravascular ultrasound examination was performed in 93 patients at 27.2+/-15.0 and 369. 7+/-23.9 days after transplantation. The maximally and minimally diseased sites were selected in each segment as defined by Coronary Artery Surgery Study classification. For each matched site, maximal plaque thickness was measured. Lesions (maximum plaque thickness >/=0.5 mm) present at baseline examination were defined as donor lesions. On follow-up, lesions that developed at previously normal sites were defined as de novo lesions. The distribution and severity of donor and de novo lesions were similar in proximal, mid, and distal segments. The de novo lesions were less focal (43% vs 74%) and more circumferential (69% vs 45%) compared with the donor lesions, but there was significant morphological heterogeneity. Similar numbers of patients with and those without donor lesions developed de novo lesions. Moreover, progression of donor lesions was not associated with the presence or absence of de novo lesions. CONCLUSIONS: Differentiation between early allograft vasculopathy from conventional atherosclerosis by distribution and morphology of lesions alone is difficult. Serial intravascular ultrasound imaging with early baseline examination is necessary to make this distinction. This distinction is important because the progression of donor lesions and the development of de novo lesions are independent of each other.     

Assessment with magnetic resonance imaging of response to radiotherapy for tongue and mouth floor tumors

The recombinant outer-surface protein A with an N-terminally truncated form (des-Cys1-OspA) from the Lyme disease spirochete Borrelia burgdorferi was expressed in Saccharomyces cerevisiae at high production levels. Since the recombinant vaccine candidate expressed in Escherichia coli exhibits low production yields and the purification of lipoproteins appears to be difficult, we have investigated the secretion of a soluble recombinant OspA in the yeast S. cerevisiae. In this way, a Leu+ derivative of S. cerevisiae cI3ABYS86 was used as the host strain transformed with an expression plasmid containing the gene encoding des-Cys1-OspA and driven by the MF alpha 1 promoter. The fed-batch culture results revealed that an efficient secretion of des-Cys1-OspA is obtained with a high production level of about 2.1 g l-1 at a cell density of 101 g l-1 cell dry weight. The accumulation of recombinant protein in the supernatant exceeds 6% of the total yeast proteins when estimated by sodium dodecyl sulphate/polyacrylamide gel electrophoresis. Moreover, des-Cys1-OspA showed lower solubilities at high cell densities and, as a consequence, a fraction of the recombinant protein precipitated. An internal cleavage of the MF alpha 1 pro::des-Cys1-OspA precursor was also detected. However, in this case the cleavage occurred at a frequency such that the large amounts of the secreted des-Cys1-OspA could be employed for the evaluation of an immunogenic effect on animal immunization. These studies will extend the knowledge of the usefulness of OspA as a vaccine for Lyme borreliosis.     

Application of intravascular ultrasound imaging to carotid artery

Although conventional angiography is utilized to assess the extent and severity of carotid artery disease, it yields only a silhouette of the vessel lumen. Intravascular ultrasound imaging (IUI), which has been developed for imaging the coronary artery, can supplement angiography by providing a tomographic perspective of the vessel wall structure. Therefore, we applied IUI (4.3F, 30MHz) to the carotid artery to evaluate the extent of arteriosclerosis, and we were successful in imaging the perspective of the carotid artery. Our results suggest that IUI is a useful device to evaluate the extent of atherosclerosis of the carotid artery.