Investigation Of Urolithiasis Research Articles

Half-dose non-contrast CT in the investigation of urolithiasis: image quality improvement with third-generation integrated circuit CT detectors.

The objective of this study is to establish the effect of third-generation integrated circuit (IC) CT detector on objective image quality in full- and half-dose non-contrast CT of the urinary tract. 51 consecutive patients with acute renal colic underwent non-contrast CT of the urinary tract using a 128-slice dual-source CT before (n = 24) and after (n = 27) the installation of third-generation IC detectors. Half-dose images were generated using projections from detector A using the dual-source RAW data. Objective image noise in the liver, spleen, right renal cortex, and right psoas muscle was compared between DC and IC cohorts for full-dose and half-dose images reconstructed with FBP and IR algorithms using 1 cm(2) regions of interest. Presence and size of obstructing ureteric calculi were also compared for full-dose and half-dose reconstructions using DC and IC detectors. No statistical difference in age and lateral body size was found between patients in the IC and DC cohorts. Radiation dose, as measured by size-specific dose estimates, did not differ significantly either between the two cohorts (10.02 ± 4.54 mGy IC vs. 12.28 ± 7.03 mGy DC). At full dose, objective image noise was not significantly lower in the IC cohort as compared to the DC cohort for the liver, spleen, and right psoas muscle. At half dose, objective image noise was lower in the IC cohort as compared to DC cohort at the liver (21.32 IC vs. 24.99 DC, 14.7% decrease, p < 0.001), spleen (19.33 IC vs. 20.83 DC, 7.20% decrease, p = 0.02), and right renal cortex (20.28 IC vs. 22.98 DC, 11.7% decrease, p = 0.005). Mean obstructing ureteric calculi size was not significantly different when comparison was made between full-dose and half-dose images, regardless of detector type (p > 0.05 for all comparisons). Third-generation IC detectors result in lower objective image noise at full- and half-radiation dose levels as compared with traditional DC detectors. The magnitude of noise reduction was greater at half-radiation dose indicating that the benefits of using novel IC detectors are greater in low and ultra-low-dose CT imaging.

The diagnostic yield of intravenous urography: a demographic study

To examine the impact of intravenous urography (IVU) on patient management in unselected patients in an effort to identify groups in which the use of urography could be reduced. The results of IVU in 235 consecutive unselected patients were assessed prospectively to establish the value of IVU in patient management. Patients were divided into subgroups on the basis of age, sex, presenting symptoms and source of referral. The percentage of examinations with findings affecting patient management was taken as the 'positive diagnostic yield.' Differences between the positive diagnostic yields of IVU in the various groups were examined using the chi 2 test. For all patients the diagnostic yield was 37.4%. In patients over 50 years of age the yield was 46% while below that age the yield fell to 20%. This difference was significant (chi 2 = 13.88, P < 0.001). There were no significant differences between the other defined groups. Specifically, patients referred by general practitioners were as likely to have an IVU abnormality as were patients referred by a hospital practitioner. Patients with painless microscopic haematuria had a lower diagnostic yield (20%) than the other groups examined but this was not significant. IVU has a high diagnostic yield in an unselected population. Although the yield is lower in younger patients IVU offers advantages over other techniques in the investigation of urolithiasis--the commonest positive diagnosis in this study. We argue that it should retain its position as the primary investigation for the majority of patients with urological disease, particularly those suffering loin pain or haematuria.

Pediatric Urolithiasis in the 1970s

We studied retrospectively 38 children who presented with urolithiasis between 1970 and 1977. The sex ratio was 1:1 and the mean age was 9.4 years. A positive family history was found in 36 per cent. Urinary tract abnormalities predisposing to infective urolithiasis was found in 7 children (18 per cent) but required voiding cystography for detection in 5. Hypercalcemia was found in 3 of 32 (8 per cent), while 28 of the 38 patients (74 per cent) had idiopathic urolithiasis. Idiopathic hypercalciuria was found in 5 of 13 patients (38 per cent) with idiopathic urolithiasis. Investigation of urolithiasis in children should include voiding cystography and measurement of urine calcium, as well as oxalate and uric acid, under home diet conditions.

An investigation of urolithiasis in two flocks of laying fowls

Urolithiasis and kidney disease as causes of significant mortality in fowls were investigated in two flocks of commercial laying birds on farms where outbreaks had occurred previously. The investigation, covering the first 10-11 months of egg production, included macroscopic and histological examination of individual cases of the disease, biochemical studies on blood samples collected at regular intervals from marked birds and the analysis of feed samples taken at the same time. The aetiology and pathogenesis of the condition was not established and the various investigations carried out did not reveal any consistent features. The possibility of an association between infectious bronchitis virus and the pathological entity described in the paper is discussed.

Epidemiological investigation of urolithiasis in the hot arid Southern region of Israel.

Epidemiological investigation of urolithiasis in the hot arid Southern region of Israel.