Endoscopic evaluation of food bolus formation and its relationship with the number of chewing cycles

It is known that solid food is transported to the pharynx actively in parallel to it being crushed by chewing and mixed with saliva in the oral cavity. Therefore, food bolus formation should be considered to take place from the oral cavity to the pharynx. In previous studies, the chewed food was evaluated after the food had been removed from the oral cavity. However, it has been pointed out that spitting food out of the oral cavity interferes with natural food bolus formation. Therefore, we observed food boluses immediately before swallowing using an endoscope to establish a method to evaluate the food bolus-forming function, and simultaneously performed endoscopic evaluation of food bolus formation and its relationship with the number of chewing cycles. The subject was inserted the endoscope nasally and instructed to eat two coloured samples of boiled rice simultaneously in two ingestion conditions ('as usual' and 'chewing well'). The condition of the food bolus was graded into three categories for each item of grinding, mixing and aggregation and scored 2, 1 and 0. The score of aggregation was high under both ingestion conditions. The scores of grinding and mixing tended to be higher in subjects with a high number of chewing cycles, and the score of aggregation was high regardless of the number of chewing cycles. It was suggested that food has to be aggregated, even though the number of chewing cycles is low and the food is not ground or mixed for a food bolus to reach the swallowing threshold.

Cognitive impairments in multiple system atrophy: MSA-C vs MSA-P

OBJECTIVE

We evaluated comprehensive neuropsychological tests and regional brain blood flow to compare cognitive dysfunction between two types of multiple system atrophy: predominant cerebellar ataxia (MSA-C) and predominant parkinsonism (MSA-P).

METHODS

Twenty-one patients with MSA-C, 14 patients with MSA-P, and 21 age- and education-matched control subjects were subjected to neuropsychological tests and SPECT. The neuropsychological tests examined general cognition, verbal and visual memory, working memory, visuospatial and constructional ability, language, executive function, depression, and anxiety, while SPECT analysis examined brain perfusion.

RESULTS

Patients with MSA-P showed severe involvement of visuospatial and constructional function, verbal fluency, and executive function compared with control subjects. Patients with MSA-C showed involvement only in visuospatial and constructional function compared with control subjects and a milder degree of involvement compared with patients with MSA-P. Patients with MSA-P tended toward a wide and severe impairment in cognitive function compared with patients with MSA-C. In addition, neuropsychological impairment in patients with MSA-P was significantly correlated with a decrease in prefrontal perfusion. This significant relation was not correlated to other factors such as age, education, and severity of cerebellar ataxia and parkinsonism, which are relevant factors associated with cognitive performance.

CONCLUSIONS

Patients with multiple system atrophy-parkinsonism show more severe and more widespread cognitive dysfunctions than patients with multiple system atrophy-cerebellar ataxia. Our results also indicate that cognitive dysfunction in patients with multiple system atrophy-parkinsonism may be associated with prefrontal involvement.

Cognitive impairment in spinocerebellar ataxia type 6

OBJECTIVE

The aim of this study was to evaluate cognitive impairment in patients with spinocerebellar ataxia type 6 (SCA6) and to verify the role of cerebellar involvement in intellectual abilities.

METHODS

Cognitive function was examined in 18 patients with genetically confirmed SCA6 and in 21 age and education matched controls using a test battery for attention, verbal and visuospatial memory, as well as executive function.

RESULTS

Verbal fluency and immediate visual memory task were markedly impaired in SCA6 compared with the control group (p = 0.007, 0.004 and 0.014, respectively). The results of the Rule Shift Cards Test was reduced in patients with SCA6, but the reduction was not significant. These cognitive dysfunctions did not correlated with CAG repeat length, age at onset, ataxic motor dysfunctional scale or depression.

CONCLUSIONS

Our results demonstrate that specific cognitive deficits occur in patients with SCA6, independent of ataxic motor dysfunction. These deficits may reflect disruption of cortico-cerebellar circuits.

Imaging of endolymphatic and perilymphatic fluid at 3T after intratympanic administration of gadolinium-diethylene-triamine pentaacetic acid

By optimizing the inversion time of a 3D inversion-recovery turbo spin-echo sequence at 3T, we obtained separate images of endolymphatic and perilymphatic space 24 hours after intratympanic administration of gadolinium contrast material. In patients with Ménière disease, endolymphatic hydrops were detected not only in the cochlea but also in the vestibule. Fusion of the 2 types of images visualized the entire fluid space of the labyrinth and the spatial relationship of the 2 spaces.

Clinical characteristics of synchronous colorectal cancer are different according to tumour location

AIMS

The purpose of this study was to investigate the clinical characteristics of synchronous cancer patients, with particular attention given to variations in tumour location.

METHODS

A retrospective evaluation of 249 synchronous cancer cases out of 3061 consecutive colorectal cancer patients.

RESULTS

Multivariate analysis of risk factors for synchronous cancer according to tumour location revealed that male gender was a significant risk for synchronous lesions in the left colon only (odds ratio=2.05, 95% confidence interval 1.34-3.13). Meanwhile, aging was a risk factor for synchronous cancer in the right colon only (odds ratio=1.05, 95% confidence interval 1.02-1.08), and in both sides of the colon (odds ratio=1.03, 95% confidence interval 1.01-1.05), but not in the left colon only (odds ratio=0.98, 95% confidence interval 0.97-1.00). In addition, patients with synchronous lesions in the right colon only tended to have adenomas in the right colon, while those with synchronous lesions in the left colon only tended to have adenomas in the left colon (each P value <0.05).

CONCLUSION

The risk factors and status of concurrent adenomas of synchronous cancer cases varied according to tumour location, suggesting that the colonic site susceptible to neoplasia varies according to patient characteristics.

Parry-Romberg syndrome with a clinically silent white matter lesion

We performed a detailed neuroimaging study in a patient with Parry-Romberg syndrome. Proton MR spectroscopy demonstrated normal spectral patterns, though conventional MR imaging revealed high-intensity areas in the entire white matter in the left hemisphere. Single-photon emission tomography showed increased perfusion in the cortex of the affected hemisphere. Pyramidal tracts and optic radiations were preserved on diffusion tensor tractography. We will correlate these neuroimaging findings with normal psychomotor development in our patient.

Transient encephalopathy with reversible white matter lesions in children

We report on two children with acute encephalopathy showing mild clinical manifestations and reversible white matter lesions. In both patients, MRI revealed high intensities on T (2)-weighted imaging and marked reductions of water diffusion in the white matter of the bilateral centrum semiovale and the corpus callosum. These abnormalities disappeared along with the neurological symptoms within a week in both patients. These children represent a characteristic group of patients among childhood acute encephalopathy.

Thyroid lesions and dioxin accumulation in the livers of jungle crows (Corvus macrorhynchos) in urban and suburban Tokyo

Wild jungle crows (Corvus macrorhynchos) captured from three different areas of Tokyo were examined to evaluate environmental contamination of dioxins. In addition to the pathologic examination of their whole body, accumulation of dioxins, mRNA expression of the aryl hydrocarbon receptor (AhR), and pentoxyresorufin-O-depenthylase (PROD) activity in the liver were determined. Marked histopathologic changes were observed in the thyroid glands, especially in the crows from the urban downtown area. Levels of dioxins and their toxic equivalents (TEQs) and AhR mRNA expression in the livers of the crows from the urban area were higher than those from the suburban area. There was a high correlation between the levels of TEQs and PROD activity. The results of the present study demonstrated that jungle crows possess AhR-mediated toxicologic pathways similar to those of mammals and suggest the possibility that the thyroidal changes observed in the adult crows from the urban areas are one of the toxic manifestations resulting from exposure to dioxins and other environmental chemicals.

Primary lateral sclerosis presenting parkinsonian symptoms without nigrostriatal involvement

We encountered three patients with primary lateral sclerosis (PLS) showing bradykinesia, frozen gait, and severe postural instability, as well as slowly progressive spinobulbar spasticity. Cranial magnetic resonance (MR) imaging showed precentral gyrus atrophy. Central motor conduction was markedly prolonged or failed to evoke a response. Positron emission tomography (PET) showed significant reduction of [18F]fluoro-2-deoxy-D-glucose uptake in the area of the precentral gyrus extending to the prefrontal, medial frontal, and cingulate areas. No abnormalities were seen in the nigrostriatal system with PET using [18F]fluorodopa or [11C]raclopride or with proton MR spectroscopy. Thus, widespread prefrontal, medial, and cingulate frontal lobe involvement can be associated with the parkinsonian symptoms in PLS.

Multiple regional 1H-MR spectroscopy in multiple system atrophy: NAA/Cr reduction in pontine base as a valuable diagnostic marker

OBJECTIVE

We performed (1)H-MR spectroscopy ((1)H-MRS) on multiple brain regions to determine the metabolite pattern and diagnostic utility of (1)H-MRS in multiple system atrophy (MSA).

METHODS

Examining single voxels at 3.0 T, we studied metabolic findings of the putamen, pontine base, and cerebral white matter in 24 MSA patients (predominant cerebellar ataxia (MSA-C), n = 13), parkinsonism (MSA-P), n = 11), in 11 age and duration matched Parkinson's disease patients (PD) and in 18 age matched control subjects.

RESULTS

The N-acetylaspartate to creatine ratio (NAA/Cr) in MSA patients showed a significant reduction in the pontine base (p<0.0001) and putamen (p = 0.02) compared with controls. NAA/Cr in cerebral white matter also tended to decline in long standing cases. NAA/Cr reduction in the pontine base was prominent in both MSA-P (p<0.0001) and MSA-C (p<0.0001), and putaminal NAA/Cr reduction was significant in MSA-P (p = 0.009). It was also significant in patients who were in an early phase of their disease, and in those who showed no ataxic symptoms or parkinsonism, or did not show any MRI abnormality of the "hot cross bun" sign or hyperintense putaminal rims. NAA/Cr in MSA-P patients was significantly reduced in the pontine base (p = 0.001) and putamen (p = 0.002) compared with PD patients. The combined (1)H-MRS in the putamen and pontine base served to distinguish patients with MSA-P from PD more clearly.

CONCLUSIONS

(1)H-MRS showed widespread neuronal and axonal involvement in MSA. The NAA/Cr reduction in the pontine base proved highly informative in the early diagnosis of MSA prior to MRI changes and even before any clinical manifestation of symptoms.

Contrast enhancement of the cochlear aqueduct in MR imaging: its frequency and clinical significance

There have been no previous reports on contrast enhancement of the cochlear aqueduct in magnetic resonance imaging. The purpose of the present study was to evaluate the frequency and significance of this finding. Thirty-one patients (15 men and 16 women; age range 18-81 years) with otologic symptoms (sudden sensorineural hearing loss, vertigo, or tinnitus) were examined using contrast-enhanced imaging on a 1.5-T MR scanner. The normal ear served as the control. Two radiologists evaluated contrast enhancement in the area of the cochlear aqueduct. Forty-eight of 62 ears (77.4%) showed contrast enhancement of the cochlear aqueduct, but no significant differences in the frequency of contrast enhancement were observed between patients with and patients without vertigo, tinnitus, sensorineural hearing loss, cerebellopontine angle tumors, or a high-riding jugular bulb. In addition, no gender- or age-related differences were noted. Contrast enhancement of the cochlear aqueduct was frequently observed, but the frequency of enhancement in symptomatic ears was not significantly higher than in control ears. The results of this study may prove helpful in avoiding unnecessary examinations and potential diagnostic confusion.

Sequential constriction of upper airway and vocal cords in sleep apnoea of multiple system atrophy: low field magnetic resonance fluoroscopic study

Low field magnetic resonance fluoroscopy was used to clarify temporal and spatial features of airway obstruction in sleep apnoea syndrome (SAS) in multiple system atrophy (MSA), as well as in obstructive SAS (OSAS). 20 patients with OSAS with severe obesity (mean (SD) age 66 (10) years; 16 men, 4 women) and 6 patients with SAS related to probable MSA (60 (9) years; 4 men, 2 women) were studied. In the OSAS group, body mass index, apnoea index, and desaturation index were significantly higher than in the MSA group. In OSAS, simultaneous obstruction extended from the retropalatal pharynx to the retroglossal during sleep on low field magnetic resonance fluoroscopy. In MSA, obstruction of upper airway followed a similar distribution, but obstruction of vocal cords followed upper airway obstruction. In contrast to OSAS, sequentially acting neural mechanisms are suspected in SAS with MSA.

Treatment of oligoasthenozoospermia with tranilast, a mast cell blocker, after long-term administration

The authors retrospectively examined whether long-term administration of tranilast improves semen parameters in severe oligoasthenozoospermia. Fifty-two patients presenting with sperm concentration of less than 10 x 10(6) sperm/mL were enrolled. Subjects were partitioned into 3 groups as follows: patients displaying an atrophic testis with elevated (FSH) (group 1), patients exhibiting normal testicular volume with elevated FSH (group 2), and patients with normal testicular volume and normal FSH levels (group 3). Tranilast (300mg/day) was administered until pregnancy was achieved or for a period of up to 12 months. Sperm concentration was significantly increased at 3 months in 16 subjects (44%) in groups 1 and 3. In group 2, sperm concentration was increased at 12 months (5 of 16 subjects; 31%). Total sperm count was obviously elevated at 3 months in groups 1 and 2, and at 6 months in group 3. Six pregnancies were achieved via natural intercourse. Tranilast, a mast cell blocker, demonstrates a certain clinical benefit in terms of improvement of semen parameters involving severe oligoasthenozoospermia, but it does not appear to afford clinical benefit in long-term administration.

Clinical study of transitional cell carcinoma of the prostate associated with bladder transitional cell carcinoma

BACKGROUND

Transitional cell carcinoma of the prostate in patients with bladder cancer appears to influence the prognosis and affects the decision about therapeutic modality. Therefore, it is important to characterize transitional cell carcinoma associated with bladder cancer.

METHODS

From April 1980 to December 1998, 81 male patients underwent total cystoprostatectomies for transitional cell carcinoma of the bladder. The 81 cystoprostatectomy specimens were examined to clarify the characteristics of prostatic involvement by transitional cell carcinoma. The extent, origin, mode of spread and risk factor of prostatic involvement as well as the prognosis were investigated. In 13 of 15 patients with prostatic involvement the prostate was examined by sequential step sections.

RESULTS

Prostatic involvement was observed in 15 of 81 patients (18.5%). Prostatic urethral involvement, invasion to prostatic duct/acinus, prostatic stromal invasion and extraprostatic extension and/or seminal vesicle involvement were recognized in 12 (80%), 14 (93.3%), six (40%), and five (33.3%) of the 15 patients, respectively. Twelve of the 15 patients (80%) with prostatic involvement had papillary or non-papillary tumors (i.e. carcinoma in situ) both in the prostatic urethra and prostatic duct. In 10 of these 12 patients (88.3%), there was contiguity between prostatic urethral and ductal tumors. Seven of the 23 patients (30.4%) with carcinoma in situ of the bladder showed prostatic involvement, which increased to 50% in the presence of carcinoma in situ of the trigone or bladder neck.

CONCLUSIONS

Eighty per cent of the patients with prostatic involvement showed papillary or non-papillary tumors both in the prostatic urethra and prostatic duct. There was a high level of contiguity between both tumors. Patients with carcinoma in situ of the trigone or bladder neck revealed significantly higher incidence of prostatic involvement.

Endoscopic ureteral incision using the holmium:YAG laser

BACKGROUND

We reviewed the results of endoscopic ureteral incision for benign ureteral stricture, ureteropelvic junction obstruction and ureteroenteroanastomotic stricture using the holmium laser.

METHODS

We carried out endoscopic ureteral incision using the holmium laser through an 8-Fr semirigid or 6.9-Fr flexible ureteroscope on 17 ureters in 15 patients. Balloon dilatation was not necessary before insertion of the ureteroscope. The stricture was incised with the holmium laser using a 200-365 microm fiber through the working channel of the ureteroscope. After completion of the incision, a 12-Fr double-J catheter was left for 6 weeks. Thereafter patients were followed by renal scan and/or ultrasound and excretory urography at 3-6 month intervals.

RESULTS

The mean operative time was 65 min (18-135 min). The stricture resolved completely in 86.7% of cases at an average follow up of 20.5 months (11-32 months).

CONCLUSIONS

The holmium laser endoscopic ureteral incision was associated with a good outcome in our series. We recommend this procedure to be employed initially because it is less invasive and has a favorable outcome.

Contrast-enhanced MR angiography of the carotid artery using 3D time-resolved imaging of contrast kinetics: comparison with real-time fluoroscopic triggered 3D-elliptical centric view ordering

PURPOSE

To evaluate contrast-enhanced MR angiography using the 3D time-resolved imaging of contrast kinetics technique (3D-TRICKS) by direct comparison with the fluoroscopic triggered 3D-elliptical centric view ordering (3D-ELLIP) technique.

METHODS

3D-TRICKS and 3D-ELLIP were directly compared on a 1.5-Tesla MR unit using the same spatial resolution and matrix. In 3D-TRICKS, the central part of the k-space is updated more frequently than the peripheral part of the k-space, which is divided in the slice-encoding direction. The carotid arteries were imaged using 3D-TRICKS and 3D-ELLIP sequentially in 14 patients. Temporal resolution was 12 sec for 3D-ELLIP and 6 sec for 3D-TRICKS. The signal-to-noise ratio (S/N) of the common carotid artery was measured, and the quality of MIP images was then scored in terms of venous overlap and blurring of vessel contours.

RESULTS

No significant difference in mean S/N was seen between the two methods. Significant venous overlap was not seen in any of the patients examined. Moderate blurring of vessel contours was noted on 3D-TRICKS in five patients and on 3D-ELLIP in four patients. Blurring in the slice-encoding direction was slightly more pronounced in 3D-TRICKS. However, qualitative analysis scores showed no significant differences.

CONCLUSION

When the spatial resolution of the two methods was identical, the performance of 3D-TRICKS was found to be comparable in static visualization of the carotid arteries with 3D-ELLIP, although blurring in the slice-encoding direction was slightly more pronounced in 3D-TRICKS. 3D-TRICKS is a more robust technique than 3D-ELLIP, because 3D-ELLIP requires operator-dependent fluoroscopic triggering. Furthermore, 3D-TRICKS can achieve higher temporal resolution. For the spatial resolution employed in this study, 3D-TRICKS may be the method of choice.

CT and MR imaging of pancreatic cancer

Recent improvements in imaging techniques have made it possible to improve the diagnostic accuracy for detection, staging, and indicating surgical resectability of pancreatic cancer. The latest advance in the computed tomography technique, is the introduction of subsecond multislice helical scanning that improves z-axis resolution in the reformatted images and three-dimensional rendering with a large volume data. Magnetic resonance imaging provides versatile information including magnetic resonance cholangiopancreatography that allows noninvasive delineation of the pancreatic and biliary duct systems. The presence of pancreatic cancer may best be evaluated by dynamic computed tomography or dynamic magnetic resonance imaging with administration of intravenous contrast material. Both computed tomography and magnetic resonance imaging are valuable for the preoperative assessment of local invasion and vascular involvement. Multislice helical computed tomography is currently considered as the best single modality for the diagnosis of pancreatic cancer as it provides excellent image quality. When advanced magnetic resonance imaging equipment is used as a primary modality, in the future, it may have a possibility to replace other imaging modalities.

Holmium:YAG laser endoureterotomy in the treatment of ureteroenteric stricture following Indiana urinary diversion

A 57-year-old man who had received radical urethrocystectomy and Indiana urinary diversion 6 months earlier was treated for ureteroenteric anastomosis stricture (left side) using a Holmium:YAG laser via antegrade approach. The availability of small (6.9 Fr) flexible ureteroscope, as well as the use of the Holmium:YAG laser has facilitated the ability to precisely incise the stricture under direct endoscopic visualization. The technique is described for laser endoureterotomy in a patient with ureteroenteric stricture following Indiana urinary diversion.

MR cisternography of the cerebellopontine angle: comparison of three-dimensional fast asymmetrical spin-echo and three-dimensional constructive interference in the steady-state sequences

BACKGROUND AND PURPOSE

MR cisternography has been used as the noninvasive screening tool of the cerebellopontine angle. The purpose of this study was to directly compare two currently dominant types of sequences for heavily T2-weighted MR cisternography.

METHODS

Three-dimensional fast asymmetric spin-echo (3D-FASE) sequences, which are 3D half-Fourier rapid acquisition with relaxation enhancement and 3D constructive interference in the steady-state (3D-CISS) sequences, were compared on a clinical 1.5-T MR unit using the same scan times. In five healthy volunteers, the contrast-to-noise ratio (C/N) between CSF and the cerebellum was measured at three locations. Then, for qualitative analysis, the quality of the labyrinth was scored on the original source multiplanar reformatted images, the virtual endoscopic images, and the maximum intensity projection (MIP) images. In 20 consecutive patients with suspected cerebellopontine angle tumors, visualization of the tumors was evaluated using 3D contrast-enhanced spoiled gradient-echo imaging as the standard of reference.

RESULTS

Both sequences showed comparable mean C/N values; however, in qualitative analysis, the scores for 3D-CISS on the source, virtual endoscopic, and MIP images were significantly lower than those on the images obtained with 3D-FASE, owing to more prominent flow and magnetic susceptibility artifacts on the 3D-CISS sequences. In all subjects, discontinuity of the semicircular canals was seen on the virtual endoscopic and MIP images obtained with 3D-CISS, owing to susceptibility artifacts, but not on those obtained with 3D-FASE. All 12 tumors were detected by both sequences, but 3D-CISS gave one false-positive result.

CONCLUSION

3D-FASE is considered the method of choice because artifacts are reduced and specificity is increased.

Virtual endoscopy of the labyrinth, using a 3D-FastASE sequence

Virtual endoscopy (VE) of the labyrinth was performed using three-dimensional (3D)-fast asymmetric spin-echo MR imaging. The spatial resolution requirements and the usefulness of zero-fill interpolation (ZIP) were evaluated, and VE was used to examine three patients. The (0.6-mm) voxel data with ZIP satisfies the minimum requirements for VE for evaluation of the complex 3D anatomy and pathology of the labyrinth. J. Magn. Reson. Imaging 2001;13:792-796.

The treatment with tranilast, a mast cell blocker, for idiopathic oligozoospermia

Although many drug treatments have been reported to theoretically improve semen parameters in male infertility, a standard method has not been established. The authors examined whether tranilast, a mast cell blocker, improves fertility and/or semen parameters in severe oligozoospermia. Seventeen patients with a sperm density of less than 10 x 10(6) sperm/mL and their fertile partners were enrolled in this study. Patients were prescribed tranilast 300 mg/day for at least 12 weeks. Semen and blood samples were collected before and after the prescription of tranilast for 12 weeks. Semen parameters, serum gonadotropins, luteinizing hormone, follicle-stimulating hormone, serum testosterone, and testicular size were evaluated. One patient complained of mild drowsiness during treatment. The sperm count was significantly increased after administration of tranilast in 7 patients (41.1%), although sperm motility was not altered. Semen volume and normal morphology were also unaltered. Three pregnancies were achieved. Endocrine profile and testicular size were unchanged. Tranilast, a mast cell blocker, is clinically useful for the treatment of severe idiopathic oligozoospermic men.

[A case of transitional cell carcinoma of the bladder in a juvenile patient]

A 15-year-old male was referred to our hospital with the chief complaint of gross hematuria. Cystoscopic examination revealed a papillary tumor on the posterior wall. Transurethral resection of the bladder tumor was performed. Histological examination of the excised tumor showed transitional cell carcinoma, grade 1, pTa. Recurrence has not been observed for about 2 years after the operation. We investigated 54 previously reported Japanese cases of bladder cancer before age twenty including the present case.

Microsurgical vasoepididymostomy with sperm cryopreservation for future assisted reproduction

BACKGROUND

Although obstructive azoospermia is treatable with microscopic seminal reconstruction, the number of patients who choose to undergo vasoepididymostomy is limited because of recent advances in assisted reproductive technology (ART). We attempted to define the outcome of surgical reconstruction in patients with suspected epididymal obstruction and no previous history of vasectomy.

METHODS

We described 40 eligible end-to-side vasoepididymostomy procedures performed on 24 azoospermic patients who had either bilateral or unilateral epididymal obstruction.

RESULTS

The overall patency rate following surgery was 54% (13/24) and for four patients (17%), natural intercourse resulted in pregnancy. Two pregnancies were initiated with intracytoplasmic sperm injections using frozen sperm collected during vasoepididymostomy.

CONCLUSIONS

In the era of modern ART, microsurgical vasoepididymostomy with cryopreservation of sperm collected during the operation is recommended for patients with epididymal obstructions.

MR imaging of the enlarged endolymphatic duct and sac syndrome by use of a 3D fast asymmetric spin-echo sequence: volume and signal-intensity measurement of the endolymphatic duct and sac and area measurement of the cochlear modiolus

BACKGROUND AND PURPOSE

In enlarged endolymphatic duct (EED) and sac (EES) syndrome, deformity of the EED and EES is congenital; however, hearing loss is acquired. To investigate the pathophysiology of progressive sensorineural hearing loss in EED and EES syndrome, we measured the volume of the EED and EES, the diameter of the EED and EES, the area of the cochlear modiolus, and the signal intensity of the EES and compared our findings against degree of hearing loss.

METHODS

Thin-section MR images of 33 ears in 17 patients with EED and EES syndrome were studied. All studies were obtained on a 1.5-T MR unit using a quadrature surface phased-array coil. Heavily T2-weighted 3D fast asymmetric spin-echo images were obtained with a voxel size of 0.3 x 0.3 x 0.8 mm without zero-fill interpolation. Two radiologists traced the areas of the EED and EES manually, and the volume was calculated. The area of the cochlear modiolus, diameter of the EED and EES, and signal intensity of the EES were also measured by drawing regions of interest manually. The signal intensity ratio of EES/CSF was calculated. These measured values were compared against audiographic data, and the degree of linear correlation was determined.

RESULTS

The volume of the EED and EES, the area of the modiolus, the diameter of the EED and EES, and the signal intensity of the EES did not show significant correlation with degree of hearing loss.

CONCLUSION

These findings suggest that there is a microscopic area of damage or fragility in the inner ear not visible even with thin-section heavily T2-weighted MR imaging.

Diagnostic utility of tumor vascularity on magnetic resonance imaging of the breast

The objective of this study was to examine the relation of tumor vascularity on magnetic resonance imaging (MRI) with differential diagnosis malignant from benign lesions and tumor invasiveness in breast carcinoma. Forty-nine patients with breast cancer or benign lesion (median 49 yrs) were examined with dynamic MRI. Scanning of the entire breast was performed at 1.5 T with a three-dimensional fast spin echo sequence, using an original polarity altered spectral and spatial selective acquisition (PASTA) technique for fat suppression. Subsequently 0.1 mmol/Kg Gd-DTPA was administered and 3-6 images were obtained. The presence or absence of intratumoral, marginal and peritumoral vascularity on MRI was recorded. The excised specimen was histopathologically examined for the size of lesion, the presence and extent of local invasion. Tumor size on MRI correlated closely with the size at morphologic examination (r = 0. 96). Intratumoral (p = 0.04), marginal (p = 0.05) and peritumoral vascularity (p = 0.01) were less common in benign than in malignant lesions. Among the latter, intratumoral (p = 0.01) and marginal (p = 0.03) vascularity were more common in invasive carcinomas than in DCIS. In the subset of invasive carcinomas (n = 31); however, the tumors exhibiting intratumoral vascularity were markedly larger (p = 0.03). The presence of intratumoral and marginal vascularity on MRI can help predict both the differential diagnosis malignant from benign lesions and the presence tumor invasion in breast carcinomas.

Water fat separation using the single acquisition "sandwich" type 3-point Dixon method to optimize knee joint scans

In this paper, we tried to evaluate the effect of water-fat separation on and to optimize the scan condition of the newly developed "Sandwiched" 3-point Dixon method at 0.35 Tesla (T), for knee joint imaging. Using a 0.35T superconductive open magnet system with a solenoid type knee coil, one male and two female normal volunteers (27-37 y.o.) underwent knee joint imaging. Each sequence provided good water-fat separated images. At 0.35T, the gradient echo provided a better contrast than the spin echo. Optimal cartilage-marrow and cartilage-fluid contrast could be obtained at a frip angle (FA) of 90 degrees. There was no significant correlation between cartilage-marrow, cartilage-fluid contrast and repetition time (TR) values within the tested range. Cartilage-fluid and cartilage-marrow contrast were both best at an FA of 90 degrees with the gradient echo sequence. TR from 350 ms to 650 ms did not cause any significant contrast difference in the fat suppressed images. This method is useful and could be the only practical choice for obtaining fat suppressed T1 weighted images for joint magnetic resonance (MR) imaging at 0.35T.

Arachnoid granulations on high-resolution MR images and diffusion-weighted MR images: normal appearance and frequency

Arachnoid granulations (AGs), protrusions into the cerebral venous sinus lumen, have been reported on cerebral venography, contrast enhanced CT, and conventional MR imaging. Although thin-sliced high-resolution MR images and diffusion-weighted images are frequently obtained, there have been no detailed reports concerning AGs on these images. In this study, the frequency and positional distribution of AGs in the transverse sinus was investigated on thin-sliced high-resolution MR images, and their appearance on diffusion-weighted MR images was evaluated. At least one AG was found in 107 of 151 subjects (70.9%). No statistically significant differences were noticed between males and females or between the right and left sides. No significant correlations between age and size or between age and the number of AGs were noted. On diffusion-weighted images, all AGs showed iso-intensity to normal brain tissue, which was higher than the reported signal intensity of arachnoid cyst and lower than that of epidermoids. In conclusion, AGs are normal structures that are frequently found in the cerebral venous sinuses on high-resolution MR images. Knowledge regarding their frequency and normal appearance would be helpful to avoid confusion between pathological processes and AGs. It is also important to know that AGs are frequently found even in the younger population.

Holmium laser incision technique for ureteral stricture using a small-caliber ureteroscope

BACKGROUND AND OBJECTIVES

The holmium laser has a short absorption depth in tissue and possesses excellent properties both in ablation and hemostasis. We have performed endoscopic incision for ureteral stricture using the holmium laser through a small-caliber ureteroscope.

METHODS

This method was used on five patients and seven ureters. The etiology of the stricture was stone scar in two patients, ureteroenteroanastomosis of Indiana urinary pouch in two, and primary in one. We used an 8F semi-rigid or 6.9F flexible ureteroscope. No prior procedures, such as balloon dilation, were necessary in any of the cases. The stricture was incised with the holmium laser using a 365-microm fiber through the working channel of the ureteroscope. The holmium laser operated at a wavelength of 2100 nm, with an output of 1.0 J/pulse at a rate of 10 Hz. After completion of the incision, a 12F Double-J catheter was left in for six weeks.

RESULTS

The mean operative time was 89 minutes. The stricture resolved completely in all cases at an average follow-up of 8.6 months.

CONCLUSIONS

The holmium laser incision for ureteral stricture using a small-caliber ureteroscope is an easy-to-perform, safe and effective procedure.

Mesonephric adenocarcinoma of the urinary bladder: a case report

We report a very rare case of mesonephric adenocarcinoma of the urinary bladder, the origin of which is still uncertain. A non-papillary and broad-based tumor was located in the trigone and bladder neck on cystoscopic examination. Pelvic magnetic resonance imaging in T2-weighted images revealed a mass invading into the muscular layer of the bladder wall. Histologic examination of bladder cup-biopsy specimens showed adenocarcinoma. She underwent total cystectomy and pelvic lymph node dissection. Histologically, the tumor was chiefly composed of cells with eosinophilic cytoplasm and partly of cells with clear cytoplasm or hobnail-shaped cells, arranged in tubular or papillary structures, and infiltrated peri-vesical fat tissues. She died of metastatic disease 22 months after surgery. To the best of our knowledge, the present case is the 19th reported in the literature.

MR imaging of the cochlear modiolus: area measurement in healthy subjects and in patients with a large endolymphatic duct and sac

PURPOSE

To evaluate the cochlear modiolus with thin-section magnetic resonance (MR) imaging in healthy subjects and patients with a large endolymphatic duct and sac, and to assess whether the cochlea is normal or abnormal in patients with a large endolymphatic duct and sac.

MATERIALS AND METHODS

MR images were obtained in 10 ears in five volunteers (group 1), 40 ears in 20 patients with bilateral sensory hearing loss (group 2), three ears in two patients with Mondini malformation (group 3), and 12 ears in seven patients with a large endolymphatic duct and sac (group 4).

RESULTS

In groups 1 and 2, all modiolar areas were larger than 4.0 mm2. In group 3, each modiolus was smaller than 2.0 mm2. In group 4, modiolar areas were smaller than 2.0 mm2 in eight ears and were larger than 4.0 mm2 in four ears.

CONCLUSION

Findings in this study confirm that a large endolymphatic duct and sac is frequently associated with modiolar deficiency, but the modiolar area is normal in some cases. This result does not support the recently proposed hypothesis that hearing loss with a large endolymphatic duct and sac is caused by the transmission of subarachnoid pressure forces into the labyrinth through a deficient modiolus.

Magnitude subtraction vs. complex subtraction in dynamic contrast-enhanced 3D-MR angiography: basic experiments and clinical evaluation

Magnitude subtraction and complex subtraction in dynamic contrast-enhanced three-dimensional magnetic resonance (3D-MR) angiography were compared using a phantom and 23 human subjects. In phantom studies, complex subtraction showed far better performance than magnitude subtraction, especially for longer echo times, with thicker slices, and without fat suppression. With complex subtraction, non-fat-suppressed studies showed contrast-to-noise ratios comparable to those in fat-suppressed studies. In human subjects, complex subtraction was superior to magnitude subtraction in 9 subjects, but comparable to magnitude subtraction in 14 subjects. There were no cases in which magnitude subtraction was superior to complex subtraction. Although the differences observed in human studies when complex subtraction was applied with thinner slices, shorter echo times, and the fat-suppression technique were not as pronounced as those seen in phantom studies, complex subtraction should be performed in dynamic contrast-enhanced 3D-MR angiography because there are no drawbacks in complex subtraction. Further research is necessary to assess the feasibility of dynamic contrast-enhanced 3D-MR angiography without fat suppression in human subjects using complex subtraction, as suggested by the results of phantom studies. If it is found to be feasible, dynamic contrast-enhanced 3D-MR angiography without fat suppression using complex subtraction may prove to be a robust technique that eliminates the need for shimming and can reduce the acquisition time. J. Magn. Reson. Imaging 1999;10:813-820.

High-resolution MR images of inner ear internal anatomy using a local gradient coil at 1.5 Tesla: correlation with histological specimen

PURPOSE

To obtain high-resolution MR images of the inner ear at 1.5 Tesla with a local gradient coil and to correlate these images with the histological specimen.

MATERIALS AND METHODS

All studies were performed on a 1.5 Tesla MR unit with a local gradient coil (23 mT/m, slew rate of 107 mT/m/ms). The cranio-facial region of a cadaver was examined using 3D-fast spin echo (FSE) imaging with the voxel size of 0.27 mm x 0.27 mm x 0.5 mm in 9 h 37 min. Two normal volunteers were examined with the same system using 3D-FSE imaging with the voxel size of 0.20 mm x 0.26 mm x 1.0 mm in 57 min. These images were correlated with the cadaver images and histological specimens.

RESULTS

On cadaver images, internal structures such as the macula utriculi, macula sacculi, crista ampullaris, lamina spiralis ossea, ligamentum spirale cochleae, modiolus, scala tympani, scala vestibuli, and cochlear aqueduct were visualized. On the images of both volunteers, the same structures were visualized as on the cadaver images.

CONCLUSIONS

This study confirmed that high-resolution MR images obtained at 1.5 Tesla can visualize inner ear internal anatomy. Knowledge obtained in this study may be of significant value for the diagnosis of pathology in the area of the inner ear.

Evaluation of sleep apnea syndrome with low-field magnetic resonance fluoroscopy

The aim of this study was to assess the upper airway status of sleep apnea syndrome (SAS) patients with low-field MR fluoroscopy. Twenty patients with clinically diagnosed SAS underwent upper airway monitoring using MR fluoroscopy for 5 min while awake and for 30 min while asleep. A 0.064-T permanent-magnet MR imaging system was used for the study. No patients required any sedative drugs because of the very small gradient noise, except in one case. No occlusion was observed while patients were awake. Nine patients showed repeated occlusion at retropalatal (Rp) pharynx, whereas 11 demonstrated both simple Rp occlusion and combined retropalato-retroglossal (Rp + Rg) occlusions (complex occlusion). The mean frequency of occlusion in complex cases was significantly higher than that in simple Rp cases (p < 0.05). Low-field MR fluoroscopy was useful in determining the occlusion level while asleep in patients with SAS because of its quiet gantry and long-term monitoring capability. The MR fluoroscopy technique should prove to be a valuable clinical tool for the diagnosis and for determining the appropriate therapy in patients with SAS.

High-resolution MR cisternography of the cerebellopontine angle, obtained with a three-dimensional fast asymmetric spin-echo sequence in a 0.35-T open MR imaging unit

High-resolution MR cisternography performed with 3D fast asymmetric spin-echo imaging (3D fast spin-echo with an ultra-long echo train length and asymmetric Fourier imaging) was optimized in a 0.35-T open MR imaging unit. The 0.35- and 1.5-T images of the two volunteers and three patients with acoustic schwannomas were then compared. The optimal parameters for images obtained by 3D fast asymmetric spin-echo imaging at 0.35 T were as follows: field of view, 15 cm; matrix, 256 x 256 x 40; section thickness, 1 mm; echo train length, 76; and imaging time, 10 minutes 44 seconds. Scans obtained from both normal volunteers showed the facial, cochlear, and superior and inferior vestibular nerves separately in the internal auditory canal on both 0.35- and 1.5-T images. All three acoustic schwannomas were depicted on both 0.35- and 1.5-T images. Screening for disease at the cerebellopontine angle and in the internal auditory canal, without the administration of contrast material on a low-field open MR imaging unit and within a clinically acceptable imaging time, may be possible. Further controlled prospective studies are required, however, before implementation on a wide basis. If proved effective, this may be of particular value for reducing healthcare costs and for imaging claustrophobic and pediatric patients in an open system.

Clinical study on recurrence in bladder cancer patients undergoing total cystectomy--statistical analysis of factors related to recurrence

A clinico-pathological study was performed retrospectively for 77 patients undergoing total cystectomy for primary transitional cell carcinoma of the urinary bladder between 1981 and 1995 to clarify the mode of recurrence, the risk factors which may affect recurrence following cystectomy and prognostic factors. Postoperative recurrence was recognized in 27 (35.1%) out of 77 patients and the one-, two- and three-year non-recurrent rates by the Kaplan-Meier method were 75.3, 64.9% and 63.3%, respectively. The duration from cystectomy to recurrence was 1 to 102 months with a mean of 12.1 months, and approximately 92.6% of recurrence occurred within two years. Among 27 patients with recurrence, pelvic recurrence, distant metastasis, both of them and urethral recurrence were recognized in 6 (22.2%), 18 (66.7%), 1 (3.7%) and 2 (7.4%), respectively as the first site of recurrence. The overall one-, three- and five-year cause-specific survival rates of the 77 patients were 84.7, 71.1% and 65.6%, respectively. Of the 27 patients with recurrence, 25 (92.6%) died of bladder cancer. Of the factors related to recurrence or prognosis, pathological stage, lymphatic invasion, venous invasion, type of infiltration and lymph node metastasis but not pathological grade or adjunctive chemotherapy were significant risk factors for recurrence and prognostic factors in univariate analysis. However, lymphatic invasion was the only significant risk factor for recurrence and prognosis in multivariate analysis using Cox's proportional hazard model.

High-resolution MR cisternography of the cerebellopontine angle: 2D versus 3D fast spin-echo sequences

BACKGROUND AND PURPOSE

The clinical usefulness of MR cisternography of the cerebellopontine angle, applying 2D or 3D fast spin-echo sequences, has been reported recently. Our purpose was to investigate the cause of signal loss in CSF in the prepontine or cerebellopontine angle cistern on 2D FSE MR images and to compare the cisternographic effects of 2D and 3D FSE sequences.

METHODS

Preliminary experiments were performed in four volunteers to assess the causes of signal loss. Initially, using a 2D cardiac-gated cine phase-contrast method with a velocity encoding value of 6 cm/s, we measured the velocity and flow pattern of CSF. Comparisons were made to assess the effects of intravoxel dephasing, amplitude of the section-selecting gradient, echo time (TE), and section thickness. Four healthy subjects and 13 patients with ear symptoms were examined, and multisection 3-mm-thick 2D images and 30-mm-slab, 1-mm-section 3D images were compared qualitatively and quantitatively. Then, 3D MR cisternography was performed in 400 patients with ear symptoms, and qualitative evaluation was performed.

RESULTS

In volunteers, the average peak velocity of CSF was 1.2 cm/s. With TE = 250, CSF may move an average of 3 mm, and can be washed out of a 3-mm-thick 2D section volume. The CSF signal relative to that of a water phantom decreased gradually as TE increased on single-section 3-mm-thick 2D images. The CSF signal relative to that of the water phantom increased gradually as section thickness increased. No significant differences were noted in intravoxel dephasing and amplitude of the section-selecting gradient. The contrast-to-noise ratio (CNR) between CSF and the cerebellar peduncle, and the visibility of the cranial nerves and vertebrobasilar artery were significantly improved on 3D images in 17 subjects. In images from 400 patients, no significant signal loss in the cistern was observed using 3D FSE.

CONCLUSION

CSF signal loss in thin-section 2D MR cisternography is mainly attributable to the wash-out phenomenon. 3D acquisition can reduce this phenomenon and provide thinner sections. The scan time for 3D acquisition is not excessive when a long echo train length and half-Fourier imaging are used. MR cisternography should be performed using a 3D acquisition.

Interactive fusion of three-dimensional images of upper abdominal CT and FDG PET with no body surface markers

The aim of this study was to propose and validate a new method of making fused images from CT and FDG PET images for the upper abdominal area with no body surface marker. PET and CT were carried out in patients with pancreatic cancer (N = 5) and mass-forming pancreatitis (N = 2). First, we determined the midsagittal plane from PET and CT data. From the difference in location of the midsagittal planes, rotations of Y (from back to front) and Z axes (from foot to head) and X translation (from right to left) were calculated. An upper pole of the kidney was determined from PET and CT data. It showed Y and Z translations. The images of the three-dimensional data sets were fused on a workstation. Reproducibility was assessed with randomly misaligned PET and CT data sets. Pancreatic cancer and its lymph node metastases were identified easily on fused images. In reproducibility assessment, the average error of rotation was 0.77 degree. The average errors of translation were 3.43, 4.70, and 9.23 mm on the X, Y, and Z axes, respectively. In conclusion, this PET/CT image registration technique is feasible and practical. It allows precise anatomical assessment of normal and abnormal FDG accumulation.

Clinical evaluation of three-dimensional MR-cholangiopancreatography using three-dimensional Fourier transform fast asymmetric spin echo method (3DFT-FASE): usefulness of observation by multi-planar reconstruction

MR-cholangiopancreatography (MRCP) is a new method that is non-invasive and permits volume data collection and three-dimensional expression. With the three-dimensional Fourier transform fast asymmetric spin echo (3DFT-FASE) method, a higher spatial resolution can be obtained both in-pain and in slice selecting direction. In this paper, the usefulness of this new technique is investigated in the clinical diagnosis of MIP images and MPR. The study was performed in 10 normal volunteers and 21 patients with abnormalities in the pancreas or bile-duct sustem. The study was done using a 1.5 Tesla super-conductive machine. The MRCP images were interpreted by three radiologists. In most cases good images were obtained. The additional clinical information provided by MPR was remarkably useful in cystic lesions, especially in mucinous cystic neoplasm of the pancreas. Even when the intestine overlapped the pancreas, it was possible to evaluate the pancreatic duct by MPR. Three-dimensional observation and clinically useful diagnosis were possible by utilizing the advantageds of the 3DFT-FASE method appears quite useful in clinical application.

[MR-cholangiopancreatography using three-dimensional Fourier transfer fast asymmetric spin-echo method (3DFT-FASE)--clinical evaluation]

MR-cholangiopancreatography (MRCP) is a new and non-invasive method. With the three-dimensional Fourier transform fast asymmetric spin-echo (3DFT-FASE) method that allows data collection as volume and three-dimensional expression, a higher spatial resolution can be obtained in the direction of both slab thickness and in-plane. In this method, analysis by multi planar reconstruction (MPR) and observation from various angle by maximum intensity projection (MIP) are available. Although further studies are required to shorten the imaging time to stop breathing only once, to use the respiratory gating or navigator echo, clinically useful diagnosis are possible utilizing by the advantages of the 3DFT method.

MR imaging of the inner ear: comparison of a three-dimensional fast spin-echo sequence with use of a dedicated quadrature-surface coil with a gadolinium-enhanced spoiled gradient-recalled sequence

PURPOSE

To prospectively evaluate the sensitivity and specificity of magnetic resonance (MR) imaging in the inner ear with a long echo train, three-dimensional (3D), asymmetric Fourier-transform, fast spin-echo (SE) sequence with use of a dedicated quadrature-surface phased-array coil to detect vestibular schwannoma in the cerebellopontine angle and the internal auditory canal.

MATERIALS AND METHODS

In 205 patients (410 ears) with ear symptoms, 1.5-T MR imaging was performed with unenhanced 3D asymmetric fast SE and gadolinium-enhanced 3D gradient-recalled (SPGR) sequences with use of a quadrature surface phased-array coil. The 3D asymmetric fast SE images were reviewed by two radiologists, with the gadolinium-enhanced 3D SPGR images used as the standard of reference.

RESULTS

Nineteen lesions were detected in the 410 ears (diameter range, 2-30 mm; mean, 10.5 mm +/- 6.4 [standard deviation]; five lesions were smaller than 5 mm). With 3D asymmetric fast SE, sensitivity, specificity, and accuracy, respectively, were 100%, 99.5%, and 99.5% for observer 1 and 100%, 99.7%, and 99.8% for observer 2.

CONCLUSION

The unenhanced 3D asymmetric fast SE sequence with a quadrature-surface phased-array coli allows the reliable detection of vestibular schwannoma in the cerebellopontine angle and internal auditory canal.