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J A Avellana

Publications and source records attributed to J A Avellana.

At least 19 recordsLinked to original sources
PubMed1992

Value of testicular ultrasound in the evaluation of blunt scrotal trauma without haematocele.

The value of ultrasound in testicular trauma with haematocele has been questioned inasmuch as the injured testis should always be explored surgically. Ultrasonography, however, plays an important role in the diagnosis and follow-up of patients with blunt scrotal trauma without haematocele. We have evaluated 17 such patients with real-time ultrasound. In 9 cases the testis and epididymis were normal to palpation, although in 6 of them parenchymal lesions, mainly subcapsular haematomas and parenchymal contusions not amenable to surgical intervention, were detected with ultrasonography. Seven patients presented with changes in the testicular or epididymal morphology at palpation and in 1 case the testes were not palpable. Ultrasonography was of great value, indicating surgery in 6 of these patients where physical examination alone was not sufficient to establish the need for surgical exploration.

Adolescent↗
PubMed1992

[A Foley-type catheter with a steerable tip].

Permanent bladder catheterization for medical or social reasons increases the risk of complications, especially urinary infection. We evaluated the usefulness of the balloon catheter with a steerable intravesical tip in reducing the volume of residual urine between the bladder neck and the balloon of the conventional Foley catheter. The results show that this new catheter affords no additional advantage over the conventional catheter.

Catheters, Indwelling↗
PubMed1992

[The imaging diagnosis of adrenal tumors].

From 1967 to 1991 we have diagnosed and treated 73 adrenal tumors in 63 patients: 12 pheochromocytomas, 24 adrenal cortical adenomas, 15 hyperplasias, 16 carcinomas, 3 myelolipomas, 2 cysts and 1 neuroblastoma. We conducted a retrospective study to analyze the preoperative images obtained by different diagnostic techniques and attempted to correlate tumor size and site with the results of the histological analysis of the surgical specimen. Nephrotomography with pneumoretroperitoneum and IV Nephrotomography were useful in detecting the increase of the size of the gland in 10 of 25 cases submitted to these procedures (40%). Arteriography as second or third technique of choice confirmed the presence of an adrenal tumor in 15 of the 21 cases evaluated by this procedure (70%). US and CT detected 94% (31/33) and 100% (33/33) of the cases, respectively. Fourteen cases were incidentally discovered by CT (7) and US (7). A direct relationship between tumor size and degree of malignancy could be established since the carcinomas had a mean diameter of 7 cm (range 5 to 12 cm). Concerning the histologic nature of the disease, specific images were found in 3 cases of adrenal myelolipoma (hyperechoic on US and of low density similar to fat on CT) and 2 cysts (anechoic with posterior band evidenced on us and liquid on CT). Radioisotopes were also utilized for tumor localization and there was positive uptake of I-131-IMBG in 2 cases of adrenal pheochromocytoma; 1 extra-adrenal (left lateral aortic paraganglioma) and 1 case of malignant adrenal pheochromocytoma with metastasis to the lungs.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Gland Neoplasms↗
PubMed1991

Effects of atrial impulse timing on AV concealed conduction in the rabbit heart.

The influence of the timing of a nontransmitted or transmitted atrial impulse on the atrioventricular (AV) conduction time of the subsequent impulse was studied in nine isolated rabbit hearts. AV conduction curves were determined by applying the atrial extrastimulus test. The extrastimulus was delivered preceded or not by an interposed atrial impulse whose coupling interval with respect to the last atrial beat of a basic train was kept constant at 100, 120, 140, 160, 175, 200, 225, 250, and 300 msec. In all experiments, there was a "concealment interval," i.e., the AV effective refractory period was longer than the atrial functional refractory period, and in seven experiments was comprised between 100 and 160 msec. For any given extrastimulus coupling interval in the presence of an interposed nontransmitted atrial impulse, AV conduction time was significantly greater than in its absence; the increase was greater than the longer the nontransmitted atrial impulse coupling interval, i.e., the shorter the subsequent transmitted impulse coupling interval with respect to the previous interposed nontransmitted impulse. The AV conduction curves relating the extrastimulus AV conduction time to its coupling interval with respect to the last atrial impulse of the basic train fitted to a hyperbolic model both in the absence of the interposed atrial impulse and in its presence (mean square residual 31 +/- 23 msec2), and the interposed atrial impulse modified the constants of the functions; the slope of the linear transformations was progressively more negative as the interposed atrial impulse was delayed. Furthermore, the effects of the interposed atrial impulse--transmitted or not--on AV conduction time of the subsequent impulse were qualitatively similar, their magnitude depending on the time elapsed were qualitatively similar, their magnitude depending on the time elapsed between the two.

Animals↗
PubMed1991

Atrioventricular electrotonic interaction in complete atrioventricular block: an experimental model using radiofrequency energy in the rabbit heart.

UNLABELLED: Provided the conditions for electrotonic transmission exist, an automatic focus surrounded by a block zone may be externally modulated. The atrioventricular (AV) electrotonic interaction was studied in 16 perfused rabbit hearts with supra-Hisian complete AV block induced using low radiofrequency energy doses (2.5 watts; 10 seconds). In nine experiments the sinus node was preserved (group I), whereas in seven it was removed maintaining an AV nodal rhythm (group II). The V-V (ventricular cycle length) and V-A (coupling of the intervening atrial beat) in both groups, and also the A-A (atrial cycle length) and A-V (coupling of the intervening ventricular beat) intervals in group II, were measured beat by beat after current delivery. The phase response curves V-V versus V-A, and A-A versus A-V showed AV interaction in five experiments from group I, and in four from group II, as follows: (1) accelerating phase response curve, characterized by a pacemaker acceleration (V-V or A-A abbreviation) at a critical V-A or A-V coupling interval; maximum acceleration could be progressively (phase response curve without rapid cross-over) or briskly (phase response curve with rapid crossover) reached; from this point onwards acceleration decreased with a further increase in V-A or A-V coupling interval (acceleration slope). (2) Biphasic phase response curve, characterized by initial delaying and late accelerating phases. Maximum acceleration and the acceleration slope were both smaller in accelerating phase response curves without rapid cross-over. On reverting complete block in two experiments, a progressive increase in maximum acceleration and acceleration slope was observed. CONCLUSIONS: (1) AV interaction in complete AV block can be manifested as accelerating or biphasic phase response curves; (2) transition from electrotonic interaction to conduction seems to be a continuum.

Animals↗
PubMed1990

[Kaposi's sarcoma in kidney transplant treated with cyclosporin and azathioprine].

We report on a renal transplant patient who had developed Kaposi's sarcoma with cutaneous involvement 20 days after transplantation. The patient had a functioning renal graft and was on immunosuppressive therapy consisting of prednisone, azathioprine and cyclosporine. Azathioprine and cyclosporine were discontinued and chemotherapy was instituted with vinblastine first and methotrexate later; however, Kaposi's tumor did not respond to the foregoing therapeutic regimen. Thirty-two months following transplantation, the kidney graft presented acute interstitial rejection that warranted graft removal. The patient is currently receiving treatment for Kaposi's sarcoma but tumor regression has not been achieved. We discuss the atypical course of this case in comparison with those reported elsewhere.

Azathioprine↗
PubMedDate not supplied

[Renal angiomyolipoma: study of 39 patients and general review].

Between 1969 and 1991, 39 patients totalling 48 renal units with renal angiomyolipoma (RAMP) were diagnosed and treated in the Urology Service of the Hospital La Paz. In 5 patients, RAMP was part of a tuberous sclerosis, and was isolated in the remaining ones. RAMP was symptomatic in 32 cases (32/48 = 66.6%), 10 with Wundrelich's syndrome, and in 24 cases (24/48 = 50%) was larger than 4 cm. In the first cases of our series, clinical diagnosis through renal arteriography was achieved in 33% (5/14) cases; later, with the arrival of ultrasound and CAT, pre-operative diagnosis was possible in 88% (30/40) of cases. There was also 2 periods with regard to treatment, the initial one with predominance of radical surgery and the present one of observation and/or conservative surgery depending on size as well as signs and symptoms. Overall, 23 nephrectomies, 2 partial nephrectomies and 6 tumorectomies were performed, while there has been 17 cases (with no histological confirmation) treated with conservative approach and followed-up with ultrasound and CAT. With an average follow up of 8.4 years (range: 0.5-20 years), there has been no local or metastatic relapse of RAMP. There was one case of lymphatic affection which was explained as evidence of RAMP's multifocal condition and not as an indication of malignancy. In 3 patients, histological examination revealed coexistence of RAMP and renal carcinoma; 2 of these patients who underwent nephrectomy are free of disease; the third patient, treated with conservative surgery (tumorectomy), showed renal carcinoma relapsed after 2 years and had it removed. RAMP's incidence, histogenesis, diagnostic methods and treatment criteria are discussed.

Adolescent↗
PubMedDate not supplied

[Evaluation of extravesical ureteroneocystostomy in kidney transplantation].

The present study evaluates extravesical ureteroneocystostomy, the technique used for reconstruction of the urinary tract in 120 kidney transplants. The urological complications ascribable to this technique were observed in 10% (12/120) and consisted of urinary extravasation (10), and ureteric obstruction (2). The treatment of the foregoing complications, which was successful in 8 cases, is described. The indications and advantages afforded by this technique in renal transplantation are discussed.

Evaluation Studies as Topic↗
PubMedDate not supplied

[Monotopic coralliform calculus and simultaneous contralateral lithiasis].

A study is made of 15 patients with monotopic coralliform stones, suffering from simultaneous, contralateral, renoureteral lithiasis. There are certain special features in these patients which we consider to be sufficient to distinguish them as a separate group amond cases of lithiasis in general and coralliform stones in particular. The high percentage of septic complications observed in these patients demand special treatment within the field of urinary lithiasis.

Adult↗