First signs of late-presenting cervical lymph node metastasis in oral cancers during follow-up.

One of the most important prognostic factors in oral squamous cell carcinoma (OSCC) is the presence of lymph node metastasis. Therefore, the early detection of late-presenting cervical lymph node metastasis is important. Although many studies have assessed diagnostic modalities for detecting metastatic cervical lymph nodes, no study has evaluated the process, especially first signs, for detecting late-presenting cervical lymph node metastasis. A retrospective analysis comparing methods for detecting the first signs of late-presenting lymph node metastasis was performed. A total of 65 OSCC patients were assessed. These patients were identified retrospectively as having presented late metastasis during follow-up after initial treatment with curative intent. The findings of four detection methods were analyzed: palpation, ultrasonography, computed tomography, and subjective symptoms. The numbers of cases identified by each method were as follows: palpation, 31 (47.7%); ultrasonography, 17 (26.1%); computed tomography, 12 (18.5%); and subjective symptoms, 5 (7.7%). Palpation played a major role in the discovery of late-presenting lymph node metastasis. In contrast, metastatic lymph nodes were detected by other methods in about half of the cases. The results suggest a possible stratification of the various methods used for metastatic lymph node detection, depending on the characteristics of individual cases.

Colour Doppler sonographic analysis of blood-flow velocity in the human facial artery and changes in masseter muscle thickness during low-level static contraction.

Muscle oedema, which can be seen as a thickness increment by ultrasonography, is important in provoking pain and fatigue during low-level contraction. Although oedema is related to the balance of inflow and outflow of blood, there are no data on the correlation between muscle thickness change and blood-flow. Blood-flow velocities in the facial artery and the muscle thickness changes were measured by colour Doppler ultrasonography in 30 healthy volunteers during 20 min contraction with 10% of maximum force. Thickness and velocity changes both reached a peak in the initial phase of contraction. The initial change of thickness did not correlate with the velocity in the facial artery, while those immediately after exercise showed a high correlation. The velocity changes in the facial artery might depend on both the general response to contraction and local metabolic or mechanical factors in the contracted masseters.

Doppler sonography of the deep lingual artery.

PURPOSE: To clarify the Doppler sonographic features of the lingual artery in normal subjects and to evaluate those of patients with cancer of the tongue. MATERIAL AND METHODS: Sixty-seven volunteers and 12 patients with cancer and/or leukoplakia of the tongue were examined with an intraoral sonographic probe. The visibility of the deep lingual artery was determined on transverse and anteroposterior images. On the transverse images, the vascular index, which was defined as the number of colored pixels, was measured on bilateral lingual arteries. Thereafter, the degree of symmetry was evaluated for normal subjects and patients. RESULTS: In normal subjects, between younger and older volunteers, there were no significant differences in visibility of the trunk but differences were found between the two groups for the dorsal branches. The vascular indices of the right and left sides were not different. The characteristic Doppler sonographic feature was vasculature in and around the tumors in the patients with cancer of the tongue. The symmetry indices of the cancer patients were significantly different from those of normal subjects. CONCLUSION: Doppler sonography should be an important procedure for evaluation of tongue neoplasms.

Three-dimensional morphology of the masseter muscle in patients with mandibular prognathism.

OBJECTIVE: To compare the morphology of the masseter muscle in patients with mandibular prognathism with that of normal subjects. METHODS: Three-dimensional X-ray computed tomography (CT) was performed on 69 patients with mandibular prognathism and compared with 91 normal subjects. The angle of the muscle direction in relation to the Frankfurt horizontal plane and the area and the ratio of length of the short to long axes (s/l ratio) on the section perpendicular to the muscle direction were measured. RESULTS: The mean angle, area and s/l ratio in patients with mandibular prognathism was 76.6 degrees (s.d. 4.4 degrees), 318.3 mm2 (s.d. 77.2 mm2) and 0.312 (s.d. 0.049), respectively. Those of the normal subjects were 65.1 degrees (s.d. 4.4 degrees), 368.3 mm2 (s.d. 97.2 mm2) and 0.393 (s.d. 0.054), respectively. The angle was significantly larger, and the area and s/l ratio were significantly smaller than those of normal subjects (P < 0.001). CONCLUSION: The morphology of the masseter muscle in mandibular prognathism is significantly different from that of normal subjects. Our results may be helpful in evaluating the results of orthognathic surgery.

Three-dimensional computed tomography imaging in dentistry.

The authors have presented several 3-D CT imaging techniques that may be useful in dentistry. MPR and dental MPR provides cross-sectional images of the jaws and the dental arches, and its utility in implant treatment planning is widely recognized. SSD allows the clinician to visualize the surface of an anatomic structure that is selected by a threshold value. Volume rendering is a powerful and flexible three-dimensional imaging technique that can create various unique images. MIP may be useful in contrast-enhanced CT examinations, such as sialography. Model production and virtual reality three-dimensional imaging may become major techniques in the near future. Although the increased radiation dose to the patients has to be considered, future imaging demands will bring more access to 3-D CT imaging by dental patients and, with adequate three-dimensional rendering techniques, more accurate diagnosis and treatment planning.

Three-dimensional computed tomographic evaluation of morphologic airway changes after mandibular setback osteotomy for prognathism.

OBJECTIVE: To observe changes in the pharyngeal airway and the hyoid bone position after mandibular setback osteotomy in 30 patients with mandibular prognathism by means of 3-dimensional computed tomography (3DCT). STUDY DESIGN: Preoperative and postoperative computed tomography (CT) examinations were performed on 17 patients treated by sagittal split ramus osteotomy with rigid osteosynthesis and on 13 patients treated by intraoral vertical ramus osteotomy without osteosynthesis. The amount of mandibular setback was measured by the preoperative to postoperative difference of the mandibular position in axial CT images. The sizes of the preoperative and postoperative pharyngeal airway were evaluated from semitransparent and crosscut 3DCT images. Postoperative displacement of the hyoid bone was evaluated by a technique to superimpose a postoperative hard tissue 3DCT image on the preoperative image. The helical scan technique was used in the CT examination. The volume rendering technique was used to create 3DCT images. RESULTS: The mean mandibular setback was 7.8 +/- 2.1 mm with a range of 5 to 11 mm. Three months after surgery, the lateral and frontal widths of the pharyngeal airway had decreased significantly in comparison with the preoperative width. The mean reduction rates of the lateral and frontal width were 23.6% and 11.4%, respectively. The diminished airway did not recover by either 6 months or 1 year after surgery in most cases. Downward and posterior displacement of the hyoid bone was seen postoperatively. There were positive correlations between the amount of mandibular setback and reduction of the lateral width of the pharyngeal airway (r = 0.54) and the amount of hyoid bone displacement (r = 0.42). There were no significant differences between the two surgical techniques. CONCLUSION: Three-dimensional computed tomography was a practical imaging technique to evaluate the morphologic airway changes. The pharyngeal airway may have irreversible narrowing after mandibular setback surgery.

Panoramic radiographic patterns of the infraorbital canal and anterior superior dental plexus.

OBJECTIVE: To describe and classify the presentations of the infra-orbital canal/groove (IOC/G) complex and anterior superior dental plexus (ASDP) on panoramic radiographs. METHODS: The frequency of occurrence and variations in appearance of the IOC/G were determined on 246 random panoramic radiographs. A classification system consisting of Types I, II and III was developed to describe the radiographic patterns of the IOC/G. RESULTS: Two hundred radiographs (81.3%) demonstrated evidence of the IOG/C. The most frequent appearance of the IOC was Type III (44.75%) closely followed by Type I (42%) and Type II (13.25%), with only minor differences in prevalence between right and left sides. Sixty one percent were bilateral. Radiologic evidence of the ASDP was noted in 29% of radiographs demonstrating an IOG/C with 12% of cases being bilateral. Three distinct radiographic patterns of the anterior superior dental plexus (ASDP) were also observed. CONCLUSION: A classification of the appearance of the IOC/G and ASDP on panoramic radiographs has been presented.

Three-dimensional computed tomography evaluation of postsurgical condylar displacement after mandibular osteotomy.

OBJECTIVE: The purpose of this study was to examine both condylar displacement of the temporomandibular joint after sagittal split ramus osteotomy with rigid osteosynthesis and intraoral vertical ramus osteotomy without osteosynthesis in patients with mandibular prognathism by means of three-dimensional computed tomography. STUDY DESIGN: In this pilot study, five patients treated with sagittal split ramus osteotomy and 5 patients treated with intraoral vertical ramus osteotomy were evaluated. A technique to superimpose a postoperative three-dimensional computed tomography image on its corresponding preoperative image was designed. Postoperative condylar displacement, rotation, and tilting were measured in three-dimensional computed tomography images. RESULTS: Within 3 to 6 months after surgery, changes in the inclination of the condylar axes were distinctly seen, although changes in the position of the condyles within the joints were minimal. In particular, outward rotation of the condylar long axes after intraoral vertical ramus osteotomy was a frequent finding. CONCLUSIONS: The three-dimensional computed tomography superimposition technique was a practical method of evaluating postsurgical condylar displacement after mandibular osteotomy.

Solitary bone cyst of the jaws: radiographic review of 44 cases.

Solitary bone cyst is a radiolucent lesion classified as a pseudocyst with a variety of reported shapes including round, oval, and irregular. In the long bones, a truncated cone shape has been described, and the fallen trabecula sign is seen in association with pathologic fracture. The purpose of this study was to classify and document the various shapes, to describe the width versus height dimensions of jaw SBCs, to determine the identifying signs of trauma, and to evaluate other reported radiographic features. Radiographs of 44 SBCs in 43 patients were studied. Sixty-four percent demonstrated the cone shape, and four subtypes of this shape were identified. Other shapes included oval (16%), irregular (16%), and round (4%). Radiographic signs of trauma were observed in 28% of the cases. No evidence of the "fallen trabecula sign" was found in this series.

Pseudo-acylceramide with linoleic acid produces selective recovery of diminished cutaneous barrier function in essential fatty acid-deficient rats and has an inhibitory effect on epidermal hyperplasia.

Pseudo-acylceramides with different acyl properties were investigated for their capacity to restore diminished barrier function in essential fatty acid-deficient rats. Daily topical applications of synthetic pseudo-acylceramides containing ester-linked linoleic acid caused a dose-dependent, significant reduction of transepidermal water loss (TEWL). Both other pseudo-acylceramides with ester-linked oleic acid or saturated alkyl chains and ordinary ceramides exhibited a poor effect on recovery of TEWL. Furthermore, pseudoceramide containing ether-linked linoleic acid, which is biologically inactive in terms of degradation by hydrolytic enzymes, also induced a significant and similar increase in the barrier function. This restoration of barrier function by pseudo-acylceramides with linoleic acid was accompanied by suppressed DNA synthesis in the EFAD rat epidermis. In UVB-irradiated guinea pig skin, topical applications of the pseudo-acylceramides with linoleic acid immediately after the exposure significantly reduced epidermal hyperplasia, secondary to markedly diminished barrier disruption, whereas linoleic acid itself did not. A comparison of both the anti-hyperplasia and the barrier recovery effects in the series of pseudo-ceramide derivatives examined revealed that the suppressive effect on the induced epidermal hyperplasia was paralleled by the recovery of the barrier defect in EFAD rats. These findings directly suggest that acylceramide with an ester-linked linoleic acid has an essential role in the epidermal permeability barrier.

The individual and combined effects of X-irradiation and hyperthermia on early somite mouse embryos in culture.

The effects of 1) X-irradiation and 2) hyperthermia at a temperature of 43 degrees C individually and in combination have been investigated using cultured 8-day mouse embryos. B6C3F1 embryos were exposed to 0.3-2.0 Gy of X-rays, 5-20 min of heating, or 5 min of heating and irradiation at 0.3, 0.6, and 0.9 Gy. Irradiation alone at 0.3 Gy showed no apparent effect on embryonic development, but irradiation at 0.6-2.0 Gy caused a dose-dependent increase in malformed embryos. Heating alone for 5 min produced no malformed embryos, while heating for 10-20 min caused malformations as a function of heating time. Combined treatments produced higher frequencies (22.2-100%) of malformations than those of the sum of the separate treatments (0-41.7%). Malformations observed were primarily microphthalmia, microcephaly, and open neural tubes. The results indicate that in cultured mouse embryos irradiation combined with a "nonteratogenic dose" of hyperthermia directly exerts an additive effect on formation of the malformed embryos. In addition, a single occurrence of left-sided tail was produced by hyperthermia alone, while four occurrences were produced in combination with radiation.

[Corticoids secretion in primary aldosteronism. I. Diurnal variation and the effect of dexamethasone (author's transl)].

For the purpose of studying the metabolism of adrenocortical steroids in primary aldosteronism, diurnal variation and the effect of dexamethasone were examined in four patients. The circadian rhythm of cortisol was observed in plasma aldosterone and corticosterone in all cases in the preoperative state. With regards to plasma progesterone, 17 alpha-hydroxyprogesterone and dehydroepiandrosterone-sulfate, however, no demonstrable change was noted. Dexamethasone was administered to two subjects for 10 days before the operation. As a result, the urinary aldosterone of one subject decreased on the 5th day after the administration but was restored to its original value on the 10th day, while the urinary aldosterone of the other subject did not decrease at all. On the first day after the operation, the value of plasma cortisol was elevated, losing its circadian rhythm. On the 7th day after the operation, the normal circadian rhythm was observed again in plasma cortisol. Plasma aldosterone was reduced to the normal range without any demonstrable changes on the first and 7th days after the operation. On the 30th day after the operation, a slight cortisol-like circadian rhythm was observed. Plasma levels of progesterone, corticosterone, 17 alpha-hydroxyprogesterone and dehydroepiandrosterone-sulfate were almost within the normal range throughout the pre- and post-operative periods. Although plasma progesterone was within the normal range, it tended to be lower in the postoperative state than in the preoperative state.

[Corticoid secretion in primary aldosteronism. II. The renin releasing test and the angiotensin II analog infusion test (author's transl)].

To study the secretion of adrenocortical steroids, the renin releasing test and the angiotensin II analog (1-Sar, 8-Ala-Angiotensin II) infusion test was performed on four subjects with primary aldosteronism. The plasma renin activities of these subjects in the preoperative state were rather low, without any response to the renin releasing test. Plasma aldosterone was, however, significantly high and showed a tendency to declineits value when the subject was in an upright position. In the preoperative state, all the subjects lacked any alterations in plasma renin activity throughout the angiotensin II analog infusion test. Though slight elevations were observed in the blood pressure of three subjects, there was no demonstrable change in plasma aldosterone. In the other subject, though blood pressure did not change, plasma aldosterone exhibited a remarkable rise as did progesterone, 11-deoxycorticosterone and corticosterone. From these data, it was suggested that in the latter subject the aldosterone secretion was sensitive to angiotensin in comparison with ACTH. Three weeks after the operation, it was observed that plasma aldosterone response decreased, while the response of plasma renin activity to the renin releasing test was normal. This is considered to be due to the diminished sensitivity of the glomerulosa of the nonadenomatous adrenal gland to angiotensin. The levels of 17 alpha-hydroxyprogesterone, 11-deoxycorticosterone and corticosterone were almost within the normal range in the pre- and postoperative state. The levels of plasma progesterone and 11-deoxycorticosterone, however, tended to be lower in the postoperative state compared with the preoperative state.