The search for the definition, etiology, and effective diagnosis of upper urinary tract obstruction: the Whitaker test then and now.

INTRODUCTION: Robert Whitaker, inspired by Dr William W Scott at the Brady Institute at Johns Hopkins and by Sir David Innes Williams at Great Ormond Street Hospital for Children in the late 1960s, spent much of his career exploring the meaning of persistent dilatation of the upper urinary tract, in an attempt to define obstruction and to find a means of diagnosing it accurately. OBJECTIVE: This is a historical review of Bob Whitaker's journey from his definition of obstruction to the inception of his eponymous test. RESULTS: In 1975, he proposed a theory to explain the pathophysiology behind obstructive hydronephrosis and megaureter. He was among the first pediatric urologists to observe that 'it is wrong… to assume that dilatation necessarily indicates obstruction', a statement that was widely stated and even appeared in the textbooks at the time. He defined obstruction as 'an increased pressure in the pelvicalyceal system of the kidney at normal physiological flow rates such that the renal function is adversely affected'. This realization led to the development of a percutaneous pressure-measuring technique at controlled flows, later referred to as the Whitaker test. It predated and later assisted in the interpretation of diuretic renograms. DISCUSSION: Whitaker questioned the etiology of 'hydronephrosis' and challenged other hypotheses proposed at the time, which often included causes of mechanical occlusion at the ureteropelvic junction (UPJ) or ureterovesical junction (UVJ). Whitaker's hypothesis is that 'obstruction' at UPJ and UVJ levels is not mechanical but the result of a failure of normal peristalsis to form and propagate a bolus. This, in turn, depends on the potentially abnormal distensibility of the renal pelvic and ureteric wall whether it be congenital or acquired. The aim of this review is to recall the history of the development of a technique to evaluate dilated upper urinary tracts and to re-evaluate various theories that might explain the etiology of the dilatation in the light of more recent evidence. Robert (or Bob, to his colleagues) Whitaker was among the founder members of the British Association of Paediatric Urologists, which now has more than 50 members, in 1992. Together with his colleagues Philip Ransley and David Thomas, Whitaker established the annual pediatric urology course for pediatric surgery and urology trainees in Cambridge, U.K., which still runs to this day. He retired from his surgical practice in 1990 and up until the present time has taught clinical anatomy in the Cambridge University School of Medicine.

Perineal sensation: an important predictor of long-term outcome in open spina bifida.

OBJECTIVES: To see if perineal sensation in infants with open spina bifida is associated with a better long-term outcome, particularly in terms of survival, renal-related deaths and incontinence. METHODS: We conducted a prospective cohort study on a complete cohort of 117 consecutive patients with open spina bifida, whose backs were closed non-selectively at birth between 1963 and 1971. A meticulous neurological examination in infancy showed that 33 (28%) of them had perineal sensation, defined as intact sensation to pinprick in at least one dermatome on one side in the saddle area (S2-4). Data recorded within 48 h of birth and during six reviews between 1972 and 2002 were used. Details of deaths were obtained from medical records and from the Office of National Statistics. RESULTS: By December 2005, 57% (67/117) of the cohort had died. There were 50 survivors with a mean age 38 years (range 35-41). More of those with perineal sensation survived than those without (23/33 v 27/84, p<0.001). This difference was mainly caused by 19 renal deaths in those lacking perineal sensation. Crucially there were no renal-related deaths in those with perineal sensation (0/33 v 19/84, p = 0.003). Among the survivors, those with perineal sensation were more likely than the remainder to be continent of urine and faeces (10/23 v 1/27, p<0.001 and 18/23 v 9/27, p = 0.002 respectively). They were also more likely to be able to walk at least 50 m (11/23 v 5/27, p = 0.027) and never to have had pressure sores (15/23 v 9/27, p = 0.025). CONCLUSIONS: A simple assessment of perineal sensation in infancy predicts long-term outcome in terms of survival, renal prognosis and incontinence in open spina bifida.

Obturator canal fat plug: a pre-hernial condition?

Although obturator hernias are rare, they are associated with a high mortality, as diagnosis is often delayed and the condition tends to occur in the elderly. Previous researchers have postulated that obturator hernias begin with invagination of pre-peritoneal fat through the pelvic orifice of the obturator canal, forming a fat plug. With chronically raised intra-abdominal pressure, or sudden weight loss, this can progress to a clinical obturator hernia. We dissected 95 Caucasian cadaveric hemi-pelvises (47 males; 48 females) in order to investigate the frequency of fat plugs and examine the validity of the current hypothesis regarding obturator hernia pathogenesis. The mean age (SD) of the specimens was 83 (9) years, with 48 (24 male; 24 female) from the left side and 47 (23 male; 24 female) from the right side. A fat plug was found in 21 canals (22%); the majority were female (71%, P = 0.03), and right sided (62%, P = 0.20). The mean (SD) length was 20.0 mm (6.3 mm), with mean diameter 5.9 mm (1.8 mm). A shallow peritoneal dimple was also found overlying fat plugs in two specimens. No visceral herniations were found. The sex and side distribution of the obturator canal fat plugs we found are similar to those of obturator hernias reported in the literature, supporting the hypothesis that fat plugs are pre-hernial. It is unlikely that fat plugs are a high-risk condition, but dimples over these plugs may be a marker of potential hernia formation.

A graphic, three-dimensional teaching model to demonstrate the topography of the human heart.

A three-dimensional graphic model of the human heart and an accompanying description are presented as a teaching aid. Each of the four chambers is represented by a cube of equal size. Drawings of the model from various angles give views of each of the surfaces and show the interatrial, interventricular, and atrioventricular grooves, and superimposed coronary arteries and cardiac veins.

A method of demonstrating intra-renal reflux.

OBJECTIVE: To develop a method for demonstrating intrarenal reflux as a permanent resin cast, and subsequently to show the relationship between the shape of the papilla and the presence and extent of reflux and to determine, by histological examination of the resin casts, the extent of filling of the nephron. SUBJECTS AND METHODS: The pelvicaliceal systems of fresh pig's kidneys were filled retrogradely with a dilute resin that sets within 2 h. The parenchyma was then macerated in potassium hydroxide to obtain the casts. RESULTS: The extent of the intra-renal reflux was variable, was usually polar and appeared independent of the injection pressure. Microscopy showed branching of the collecting ducts and nephron filling to the proximal tubules. CONCLUSION: This method could prove a useful tool in the further study of intra-renal reflux.

Surgical outcome of orchidopexy. II. Trapped and ascending testes.

OBJECTIVE: To review the outcome of orchidopexy in boys with testicular ascent. PATIENTS AND METHODS: The case notes of all the boys who underwent orchidopexy over an 18-year period, under the care of a single consultant, were collected. The reports of patients who at the initial assessment had normally descended testes and subsequently developed maldescent, were reviewed. RESULTS: At the time of the initial assessment, 69 boys (77 testes) had normally descended testes but subsequently developed maldescent. In the intervening period, 37 of these patients (38 testes) had undergone inguinal surgery for a hernia or a hydrocele (trapped testes). The remaining 34 patients had not undergone surgery and were designated as having an 'ascending testis'. The results of surgery were excellent in all but six cases. Of these, five testes failed to reach the bottom of the scrotum and one was excised. A hernial sac was found in 16 of 28 boys with a trapped testis in whom the data was recorded. CONCLUSION: Testicular ascent is uncommon and can occur spontaneously or following ipsilateral groin surgery where scarring is a likely aetiological factor. The results of surgery are usually excellent.

Surgical outcome of orchiopexy. I. Previously unoperated testes.

A total of 1209 undescended testes in 961 boys who had no previous surgery for this problem have been reviewed with particular regard to the outcome of surgery in relation to the pre-operative and intra-operative assessment of the position of the testis. A third of impalpable testes were found at operation in the abdomen, a third in the inguinal canal and a quarter in the superficial inguinal pouch; 1% of all testes and 7% of impalpable testes were absent; 96% of all testes reached the scrotum at operation and this figure included 69% of abdominal and 94% of canalicular testes. In all 24 testes were excised--7 of which were abdominal, 8 canalicular and 9 were in the superficial inguinal pouch. The generalisation that the higher the undescended testis before operation the poorer the result, does not always hold true.

Urological trauma.

Major urological trauma is life threatening and frequently associated with trauma to other organs. A conservative approach to lesser degrees of damage to the kidney is fully justified whilst a shattered kidney or a pedicle injury calls for surgical exploration. Renal injuries between these two extremes require careful assessment and clinical judgement to decide the best management. An intravenous urogram remains the mainstay of investigation but computed tomography, ultrasound and arteriography can be useful in some circumstances. The management of urethral trauma remains controversial and depends largely on the assessment of whether the posterior urethra is partially or completely ruptured. There remain two schools of thought concerning early or late intervention but all are agreed that suprapubic diversion is essential and that a urethral catheter should not be passed blindly in the initial stages. A ruptured bladder should always be repaired and early intervention is recommended for ureteric injuries. Severe trauma to the testis is best managed operatively to reduce the morbidity.

Surgery for hypospadias fistula.

The results of 12 years' experience in the surgical treatment of hypospadias fistula are presented. Overall, there was a success rate of approximately 50% for each attempt at surgical closure of a fistula. The chances of success were not significantly influenced by the number of previous surgical procedures. The best results were obtained with fistulae on the shaft of the penis which were closed with mucosal inversion and advancement of a skin flap over the fistula.

A new device for self-catheterisation in wheelchair-bound women.

The Deavin-Hunt device is designed to help paraplegic and incontinent women to catheterise themselves whilst in a wheelchair. Such patients with neuropathic bladder might otherwise be unable to use intermittent catheterisation, an effective method of controlling incontinence and preserving the kidneys.

Ultrasound and plain X-ray screening in childhood urinary tract infection.

A group of 309 children over the age of 2 years was investigated with ultrasound and plain X-ray for suspected urinary infection. In 29 cases there were abnormal findings and in 10 the abnormalities were confirmed with cystography and intravenous urography. Of 280 children whose ultrasound and plain X-ray findings were normal, 26 re-presented with further symptoms and investigation with cystography and urography showed abnormalities in only 4. The remaining 254 children have remained well and have been spared the uncomfortable and potentially dangerous examinations of cystography and urography.

Maps for diagnosis and management of antenatal urinary tract dilatation.

Despite advances in radiological imaging techniques, the ideal management of antenatally diagnosed hydronephrosis remains controversial. A map, showing diagnostic and management pathways, has been designed in an attempt to provide maximum information from the most appropriate and minimum number of investigations.