Minimally invasive percutaneous nephrolithotomy guided by ultrasonography to treat upper urinary tract calculi complicated with severe spinal deformity

ABSTRACT Objective: To report our experience of minimally invasive percutaneous nephrolithotomy(MPCNL) in managing upper urinary tract calculi complicated with severe spinal deformity. Materials and Methods: Between August 2001 to December 2012, 16 upper urinary calculi in 13 patients with severe spinal deformity were treated by MPCNL. Preoperative investigation of the respiratory function, evaluation of anatomy by intravenous urography (IVU) and CT scan, and preoperative kidney ultrasonagraphy with simulation of the percutaneous puncture were performed in all patients. The percutaneous puncture was guided by ultrasonography. Results: A total of 19 MPCNL procedures were performed in 16 kidneys, with an average 1.2 procedures in each kidney. Three kidneys needed two sessions of MPCNL, and 2 kidneys needed combined treatment with retrograde flexible ureterscopic lithotripsy. All procedures were successfully completed with no major complications during or after surgery. The mean (range) operative duration was 67 (20-150) min and the mean postoperative haemoglobin drop was 1.0 (0.2-3.1) g/dL. Complete stone-free status was achieved in 14 kidneys. At a mean follow-up of 48(3-86) months, recurrence of small lower calyx stone was detected in one patient. Recurrent UTI was documented by urine culture in two patients and managed with sensitive antibiotics. Conclusion: PCNL for patients with severe spinal deformities is challenging. Ultrasonography-assisted puncture can allow safe and successfully establishment of PCN tract through a narrow safety margin of puncture and avoid the injury to the adjacent organs. However, the operation should be performed in tertiary centers with significant expertise in managing complex urolithiasis.

Pilot Study of Low-Dose Nonenhanced Computed Tomography With Iterative Reconstruction for Diagnosis of Urinary Stones

PURPOSE: To evaluate the efficacy of low-dose computed tomography (LDCT) for detecting urinary stones with the use of an iterative reconstruction technique for reducing radiation dose and image noise. MATERIALS AND METHODS: A total of 101 stones from 69 patients who underwent both conventional nonenhanced computed tomography (CCT) and LDCT were analyzed. Interpretations were made of the two scans according to stone characteristics (size, volume, location, Hounsfield unit [HU], and skin-to-stone distance [SSD]) and radiation dose by dose-length product (DLP), effective dose (ED), and image noise. Diagnostic performance for detecting urinary stones was assessed by statistical evaluation. RESULTS: No statistical differences were found in stone characteristics between the two scans. The average DLP and ED were 384.60+/-132.15 mGy and 5.77+/-1.98 mSv in CCT and 90.08+/-31.80 mGy and 1.34+/-0.48 mSv in LDCT, respectively. The dose reduction rate of LDCT was nearly 77% for both DLP and ED (p<0.01). The mean objective noise (standard deviation) from three different areas was 23.0+/-2.5 in CCT and 29.2+/-3.1 in LDCT with a significant difference (p<0.05); the slight increase was 21.2%. For stones located throughout the kidney and ureter, the sensitivity and specificity of LDCT remained 96.0% and 100%, with positive and negative predictive values of 100% and 96.2%, respectively. CONCLUSIONS: LDCT showed significant radiation reduction while maintaining high image quality. It is an attractive option in the diagnosis of urinary stones.

Pilot Study of Low-Dose Nonenhanced Computed Tomography With Iterative Reconstruction for Diagnosis of Urinary Stones

PURPOSE: To evaluate the efficacy of low-dose computed tomography (LDCT) for detecting urinary stones with the use of an iterative reconstruction technique for reducing radiation dose and image noise. MATERIALS AND METHODS: A total of 101 stones from 69 patients who underwent both conventional nonenhanced computed tomography (CCT) and LDCT were analyzed. Interpretations were made of the two scans according to stone characteristics (size, volume, location, Hounsfield unit [HU], and skin-to-stone distance [SSD]) and radiation dose by dose-length product (DLP), effective dose (ED), and image noise. Diagnostic performance for detecting urinary stones was assessed by statistical evaluation. RESULTS: No statistical differences were found in stone characteristics between the two scans. The average DLP and ED were 384.60+/-132.15 mGy and 5.77+/-1.98 mSv in CCT and 90.08+/-31.80 mGy and 1.34+/-0.48 mSv in LDCT, respectively. The dose reduction rate of LDCT was nearly 77% for both DLP and ED (p<0.01). The mean objective noise (standard deviation) from three different areas was 23.0+/-2.5 in CCT and 29.2+/-3.1 in LDCT with a significant difference (p<0.05); the slight increase was 21.2%. For stones located throughout the kidney and ureter, the sensitivity and specificity of LDCT remained 96.0% and 100%, with positive and negative predictive values of 100% and 96.2%, respectively. CONCLUSIONS: LDCT showed significant radiation reduction while maintaining high image quality. It is an attractive option in the diagnosis of urinary stones.

Intravenous urogram as a first line investigation in comparison with ultrasound

The objective of was to evaluate the usefulness and efficacy of intravenous urogram in patients with urinary tract pathology detected on ultrasound and X-ray KUB. The duration of the study was from September 2007 to August 2009 and a total of 250 patients were included in this cross-sectional study by non probability purposive sampling technique. Ultrasound scans and intravenous urograms were conducted by/under direct supervision of consultant radiologist. Out of 254 patients, four were unable to complete the intravenous urogram due to reaction to the contrast medium; hence a total of 250 patients were included in the final study. There were 66 male and 184 female patients. Calculi [renal, ureteric and vesical] were seen in 139 patients, pefviureteric Junction obstruction in 9, double collecting system and/or ureter in 6, neurogenic bladder in 13, horseshoe/pancake kidney in 2, ectopic kidney in 1, ureterocele in 2, cystocele in 1 and bladder mass in 7 patients. In 14 patients, the tests conducted were inconclusive and further investigations were advised. 28 patients had no detectable urinary tract pathology on any of the diagnostic modality. Intravenous urogram should not be performed routinely as a first line investigation in every patient presenting with flank pain. However, in congenital anomalies, intravenous urograms are needed and should be performed after a preliminary ultrasound

Non-contrast renal CT scan findings: a retrospective review

To evaluate the findings of unenhanced Non-contrast Renal Computed Tomography in patients with flank pain. One hundred-seventy eight seven patients with flank pain were referred for unenhanced renal computed tomography at Prince Ali Hospital between November 2008 to February 2009. The original films of each patient were reviewed and the presence of urinary tract calculi was recorded. other urinary abnormalities were also noted. Out of 178 study population, 73 patients [41%] were reported as normal, 59 patients [33%] having hydronephrosis. The stone was located in the upper third of the ureter in 27 patients [45.8%]. Thirteen patients on the right side and 10 on the left. 12.4% were found to have various renal abnormalities. Unenhanced Renal Computed Tomography is an accurate investigation for determining the presence or abscence of urinary tract calculi in patients complaining of flank pain. It identifies renal and uretric stones; location and size. Other causes of flank pain can also be identified

Combined urethrolithotomy with vesicolithotomy in an 18-months old boy

We present a case of 18 months old male child who reported with acute urinary retention. He had a urethral calculus along with a vesical calculus. He was subjected to combined external urethrotomy and open vesicolithotomy in one sitting. The patient made a smooth post operative recovery and was followed up for 6 months

Validity of ultrasound and KUB in detecting urinary stones in renal colic

To measure the validity of ultrasound [U/S] plus urinary system radiological examinations [KUB] in detecting urinary stones in patients with renal colic. Design: Case series descriptive study. Setting: The study was conducted in Al-Zahrawi Teaching Hospital and Al-Rahma Private Hospital, Mosul, during the period from June 1996 to June 1997. Participants: One hundred, fifty-five patients [97 males, 58 females aged 5-55 years] with renal colic who attended the two mentioned hospitals, formed the group of cases. Main outcome measures: KUB and U/S examinations were done for all cases. Intravenous Urography was performed for 35 cases only. Urinary stones were detected in 130 patients using U/S and KUB. U/S detected the stones In 122 of them. The sensitivity of U/S alone in detecting urinary stone is [94%], a value that is improved significantly when U/S was combined with KUB examination [100%]. U/S correctly diagnosed all 116 patients with hydronephrosis plus stone. U/S with KUB can replace IVU in detecting urinary stone in patients with renal colic. Their combination rarely misses a urinary stone

Radiological evaluation of obstructive uropathy in children

Early detection of obstructive uropathy in children is of crucial importance as it leads to prevention of a number of complications and impending renal failure. A series comprising of 51 patients from both sexes up to the age of 12 years was studied. The imaging modalities used were plain films of abdomen [KUB], ultrasonography [USG], intravenous urography [IVU], micturating cystourethrography [MCUG] and ascending [retrograde] pyelography. The commonest cause of obstruction seen was due to calculi in the renal tract. Ultrasonography proved to be highly sensitive in picking up early cases of obstruction. Male children were affected more often than female children. Obstruction in urinary passage at all levels was seen, extending from kidneys to the urethra. It was also seen that obstruction was unilateral, bilateral, acute, chronic, complete, incomplete, and painful or silent. In view of our study, routine screening ultrasound examination of every child is advised to detect silent cases of unilateral obstruction

Particular aspects in pediatric urolithiasis

Seventy children [6m - 14 ys] having urinary stones living as residents in Saudia Arabia were reviwed over 3 ys period [1991-1994]. The clinical manifestations of upper urinary stones in infancy Include; failure to thrive, anorexia, gastro-intestinal troubles. Interrupted stream [50%], retention of urine [50%], intermittent erection [2.9%], straining [8.6%]; holding and scrubbing of penis [4.3%] were the presentation for lower urinary stones. in the preschool age B.M, vague abdominal pain, frequency and nocturnal enuresis were the most common, presentation, Lion pain was encountered in 60% of the primary school age, while gross hematuria in 10% of cases. Radiological study; all stones were radloopaque except 7 cases. Upper urinary stone showed the highest incrdence [43] cases [38k + 5U.] Lower urinary stones in 15 cases; stone passers in 8 cases while stones in more than one site in 4 cases, Calculi of the same chemical composition presented variable shadows in the K.U.B. anatomical abnormalities were noticed in [7.2%] of cases. 2 with malrotation, 2 with bil. pelvi ureteric obstruction and one case with reflux. The majority of the stones were of mixed nature and ca. oxalate was the main component Urinary tract infection reported in [4.3%]. Metabolic errors could be a trivial process at the time of stone formation as indicated by biochemical profile

Ultrasonography in acute flank pain.

In 58 patients with acute recurrent or persistent flank pain, straight x-ray (kidney, ureter, bladder region) detected stones in the urinary tract in 50 cases (86.2%), whereas ultrasonography detected stones in the urinary tract in 55 patients (94.8%). Ultrasound also detected unilateral hydronephrosis in 20 patients (34.48%). The presence of calculus was subsequently proved by intravenous urography/surgery or spontaneous passage. Ultrasonography is safe, quick, reliable and most effective diagnostic tool in such cases in rural areas. Intravenous urogram should be reserved for cases which need surgical intervention.

Investigation of urinary calculi by infrared and emission spectrography

A complete picture about the structure and the composition of urinary calculi is found by both IR and emission spectra of the elements. From the results it is adviced that these techniques could help in differentiation between deferent types of calculi