Biomedical subjects

F Colombo

Publications and source records attributed to F Colombo.

At least 109 records · Page 6Linked to original sources

PubMed1994

Modified corporopexy as a new approach to the treatment of congenital rotation of the penis.

Congenital anomalies of the penis expressed in various forms of flexures can be associated with a rotation of the shaft. An asymmetrical insertion of the suspensory ligament on the dorsal surface of the tunica albuginea often accounts for corporal rotation. This distorts the spatial relationship between the corpora cavernosa and the pubic bone. The two corpora may overlap and the shaft is partially rotated. For the surgical treatment of these defects we proposed (1989) a technique of contrarotation of the tunica albuginea which was later abandoned because it was too invasive. We developed a technique based on the ipsilateral re-suspension of the suspensory ligament of the penis between the tunica of the lower corpus and the pubic symphysis to restore the true axis. The neurovascular adnexa, the corpora cavernosa, and the corpus spongiosum remain untouched.

Adolescent↗

PubMed1994

[Erectile complications after radical surgery for penile plastic induration].

The radical surgical option we propose for Peyronie's disease consists in removing the sclero-hyalinotic focus of disease and replacing it by an autologous dermal graft taken from the upper outer thigh area. Between 1981 and 1991, we operated 335 patients with IPP, 152 of whom underwent plaque excision and dermal graft. All could be assessed at two-year follow-up. Two main complications were observed: mild penile flexure due to scar retraction of the graft (35% of cases), and partial erectile deficit with decreased corporal rigidity (17% of cases). The degree of the graft retraction is linked to the individual's histologic response. A mild deviation of the penis can occur some months after surgery and is not a relapse flexure due to disease progression (as it should have evolutive characteristics) but is mere scar retraction and will spontaneously regress. As the patient will date the onset of a postoperative erectile deficit from the time of the operation, it is advisable to assess preoperatively the erectile ability of all patients. Furthermore, an impaired erectile response could result from hypoaesthesia of the glans, post-surgical stress, and fibrosis of the erectile tissue. A retrospective assessment of radical surgery cases involving plaque excision and dermal graft lead us to propose this option where precise indications apply, providing the presence of other alterations of the erectile function are pre-operatively assessed.

Cicatrix↗

PubMed1994

[Realities and limitations of the diagnosis of erectile impotence: radical urethro-prostato-cystectomy as a human experimentalmodel].

Veno-occlusive dysfunction (formerly called "venous leakage") is a clinical-radiographic manifestation of a multi-aetiology syndrome, the pathogenesis of which is to be sought in intrinsic damage to the erectile tissue. It has been attributed to psycho-neurogenic, neurovascular and local--physical factors. The unsatisfactory results of the various surgical techniques proposed (venous ligatures, crural plication, corporopexy) can be explained by the formation of vicarious venous circles, a phenomenon which occurs regardless of the type of procedure adopted and which is the direct consequence of the alteration of the occlusive mechanisms intrinsic to the erectile tissue. At the Urological Institute of the University of Milan, a study has been carried out with the aim of experimentally assessing these aetiopathogenetic hypotheses. 48 sexually potent patients were selected from those scheduled for extensive surgical procedures on account of malignant pathologies of the pelvic cavity (urethro-prostato-cystectomy, radical prostatectomy). The protocol included a series of examinations before and after the operation (at three months): computerised recording of nocturnal erections (NPT test, three consecutive nights), dynamic penile Doppler velocimetry, dynamic cavernosometry/graphy, examination of bulbocavernosus reflex. The goal of the study was to evaluate the haemodynamic consequences of the massive venous ligatures effected during these operations (periprostatic plexus, deep dorsal vein, spongio-cavernous connections). There were 28 cases of radical prostatectomy and 20 cases of radical urethro-prostato-cystectomy. Among the cases of radical prostatectomy, the extrafascial retropubic technique was used for 14 patients, the monolateral nerve-sparing procedure was applied for 10 patients (stage B1) and the transperineal approach was used for 4 patients (the most recent).(ABSTRACT TRUNCATED AT 250 WORDS)

Collateral Circulation↗

PubMed1994

[Erectile function and ablative surgery of penile tumors].

The Authors try to show the possibility to combine radical excision with minimal invasiveness in the surgery of penile cancer. The focal point of every therapeutic decision is correct clinical staging. Unfortunately there's some confusion in the two international staging systems (TNM and Jackson's classification). In fact it's not clear the anatomical difference between epithelioma of the glans infiltrating corpus spongiosum and subcoronary epithelioma of the shaft infiltrating the corpora cavernosa. It's obvious that the infiltration of the corpora cavernosa is a far more aggressive oncological manifestation than that of tumour infiltrating the corpus spongiosum. So we consider Jackson's classification more congenial. In terms of surgery this anatomical independence makes it easy to consider the corpora cavernosa as a distinct entity, so they remain perfectly functional when separated from the glandulo-spongio-urethral unit with its vasculo-nervous bundle. This makes conservation of the erectile function, when clinical staging show us that the tumour is not infiltrating the corpora cavernosa. The Authors show their results, which seem to be rather good.

Humans↗

PubMed1994

[Large cutaneous penile flap in the tubular reconstruction of the urethra in complex recurrent and extensive bulbar-membranous strictures].

The surgical treatment of choice for bulbar-membranous urethral strictures should remove the stricture and achieve an end-to-end anastomosis between two spatulated surfaces to achieve better patency (Turner-Warwick technique [13]). When this is not possible because of recurrence, complex or longer strictures the problem is to choose between various candidate tissue types susceptible of forming a dependable neourethra. With this in view, we have used over the last twenty years a wide range of urethroplastic operating techniques using of scrotal skin [4], bladder mucosa free grafts [3], and dermo-epidermal free mesh grafts [10]. We achieved a significant improvement of the postoperative results with a procedure originally proposed by Quartey [9]. A well vascularised flap is dissected from the whole dorsal penile skin, drawn as far as the perineum and pulled laterally to the cavernous bodies to form the neourethra. We can thus depend on suitable and viable tissue of up to 13 cm in length. A large scalped area of skin is corrected by covering the surface of the penis with a free epidermal mesh graft. Between February 1989 and December 1991, 28 patients with relapsed bulbar-membranous complex urethral strictures underwent urethroplasty with a penile-skin flap. Normal urethro-cystographic imaging and urinary flowmetry figures showed at a three-month follow-up. All patients reported satisfactory micturition and no fistula occurred. Erectile deficiency was not reported.

Adult↗

PubMed1994

Linear accelerator radiosurgery of cerebral arteriovenous malformations: an update.

One hundred eighty patients affected by cerebral arteriovenous malformations (AVMs) underwent radiosurgical treatment in our department. One hundred fifty-three patients have been treated with complete irradiation of the entire AVM nidus. In 27 patients (with large and/or three-dimensional irregular target volumes), only part of the nidus was covered with a dose adequate for obliteration. Follow-up ranged from 88 to 1 months (mean, 43.1 mo). Angiographic control was performed at 12, 24, and 36 months until complete obliteration was attained. The complete obliteration rate was 46% at 1 year and 80% at 2 years. We observed 15 hemorrhages after treatment, and five patients died from them. No bleeding took place after complete angiographic obliteration. The aim of this study is to evaluate the effect of irradiation on bleeding risk after radiosurgery and before complete obliteration. Inclusive parameters of patients considered at risk were as follows: 1) all patients in the time lapse between irradiation and demonstrated complete angiographic obliteration; 2) all patients in the time lapse between irradiation and definitive treatment either by surgery or embolization; and 3) all patients in the time lapse between irradiation and death. These groups include all irradiated patients who still had incompletely obliterated AVMs. They were stratified starting from 0 time (the date of radiosurgery), and the hemorrhages were evaluated every 6 months. In totally irradiated cases, the bleeding risk decreased from 4.8% in the first 6 months after radiosurgery to 0% starting from the 12th month of the follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

Time dependence of residual tissue viability after myocardial infarction assessed by [18F]fluorodeoxyglucose and positron emission tomography.

Areas of myocardial infarction may retain glycolytic activity and this finding is indicative of tissue viability and predictive of functional recovery after revascularization. In order to assess the relation between the time elapsed from the occurrence of acute myocardial infarction and persistence of myocardial metabolic activity in the infarcted tissue, we prospectively studied 65 patients with previous myocardial infarction diagnosed clinically and by electrocardiographic (Q wave) and enzymatic criteria. All patients underwent coronary angiography and contrast left ventriculography, evaluation of regional myocardial glucose metabolism (in the fasting state) by positron emission tomography (PET) with 2-[18F]fluoro-2-deoxy-D-glucose ([18F]FDG), and assessment of myocardial perfusion by single photon emission computed tomography (SPECT) with technetium-99m methoxyisobutyl isonitrile (99mTc-MIBI). Based on the regional metabolic and perfusion findings, patients were divided into 2 groups, depending on the absence (group 1, 26 patients) or presence (group 2, 39 patients) of [18F]FDG uptake in the underperfused regions. Areas of underperfusion at rest, consistent with the clinically identified myocardial infarction site, were observed in all patients. Severity of coronary artery disease, presence of collaterals, number of hypocontractile segments, and wall motion score did not differ significantly in the 2 groups. The time elapsed from the infarction was significantly greater (1,860 +/- 1,333 days) in group 1 than in group 2 (92 +/- 115 days; p < 0.0001). Exercise caused an increase in severity and/or extent of resting perfusion abnormalities in a greater proportion of patients of group 1 (53% vs 23%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Analysis of dosimetric measurements in linac radiosurgery calibration.

The aim of this paper is to analyse the dosimetric parameters of a linear accelerator used in radiosurgery treatments. The influence of these parameters on the resulting dose distribution are basic for delivering the predefined dose to the vascular or oncological target volume. Several dosimetric methods have been used to define the output factors for small fields. The thimble and the Markus chambers, TLD and film dosimetry are investigated; all these dosimetric systems give reliable and almost similar results if used in the correct way. In the determination of tissue maximum ratio (TMR) the response curves obtained by ionometric and film dosimetry were investigated. For TMR determination the use of the Markus chamber and the correction factors to be applied as a result of the small dimension of the field were also investigated.

Calibration↗

PubMed1993

From radiotherapy to stereotactic radiosurgery: physical and dosimetrical considerations.

The aim of this presentation is to analyse the mechanical and dosimetrical parameters of the linear accelerator used in stereotactic radiosurgery. The use of the thimble and Markus chambers, TL and film in small field dosimetry are investigated. To determine the optimal irradiation technique and dose distribution, the dose volume to healthy tissue is considered.

Humans↗

PubMed1993

Is there still an avoidable fraction of post-operative thromboembolic complications with heparin prophylaxis? The results of a case-control surveillance. Collaborative Group on Heparin Prophylaxis in Surgery (S.E.P.E.C.).

A case-control multicenter study was set up in 68 general and specialistic wards in Italian regional hospitals in order to assess whether underuse of heparin prophylaxis may account for at least a fraction of the thromboembolic events still occurring in surgical patients. 100 cases with clinically relevant thromboembolic or hemorrhagic events occurring during hospitalization for major surgery and 200 controls were identified. Controls were selected among patients not presenting any of the events under study during the same period of observation and were matched with cases for age, sex, and type of surgery. The results of the study suggest that heparin use in routine conditions of care closely reflects the "consensus" knowledge, patients at higher risk (specifically orthopedic surgical patients, those with varicose veins or with preoperative bed rest longer than 3 days) being treated more frequently with heparin. Absence of heparin prophylaxis does not appear to represent a specific risk factor for the occurrence of index events (OR 0.73, 95% CI = 0.42-1.26). Despite the higher rates of heparin exposure, the presence of varicose veins is associated with a statistically significant increase in the risk of postoperative complications (OR 2.23, 95% CI = 1.07-4.65). This study indicates that among known pre- and peri-operative risk factors only varicose veins may be unprotected by the current prophylaxis practice.

Adult↗

PubMed1993

[Anatomo-functional changes in the prostate and seminal vesicles with aging].

The anatomo-functional modifications of the prostate and the seminal pathways during the genital apparatus aging, (prostatic hyperplasia and hypotrophy of the seminal pathways and testis), are caused by hormonal modifications (inconstant increase of the gonadotropins LH-FSH, decrease of the peripheric utilization of testosterone, alterations of the adrenal secretion), by anatomical involutions (degenerations of the glandular, stromal and vascular components).

Aged↗

PubMed1993

Repair of a recurrent urethrovaginal fistula with an island bulbocavernous musculocutaneous flap.

This paper describes a case of recurrent postpartum urethrovaginal fistula. The extent of the vaginal tissue loss and the perilesional scarring made direct closure of the defect not practicable. After suturing of the urethra, the anterior vaginal wall was reconstructed with an island bulbocavernous musculocutaneous flap raised from the left labium majus. Seven months after surgery, the flap healed well, and cystography showed a regular voiding without periurethral suffusions. Healing of thedonor site also was aesthetically satisfactory.

Adult↗

PubMed1993

[Changes in sexuality and fertility in the elderly: ejaculation].

After the remark of the own results on an epidemiological research about andropausal sexual problems, the Authors analyze the alterations of ejaculatory mechanism with elderly, focusing frequency and etiopathogenesis. They underline the need of prevention of ejaculatory disturbances deriving from chronic disease or of iatrogenic origin.

Aged↗

PubMed1993

[Andrologic problems in prostatic carcinoma].

In our opinion, the attempt to save the sexuality and the erectile ability in a patient with a prostate cancer, in the respect of an absolute oncological radicality, should be recommended since potency represents for the patient a primary aspect in the quality of residual life. At the Institute of Urology of the University of Milan a study to identify pathogenetic mechanisms leading to erectile failure in the various phases of a prostate cancer was performed. From January 1988 to December 1993, 36 patients (range 50-60 years old) suffering from prostate cancer B1 stage (14 pts), B2 (20 pts) and C (2 pts) underwent to radical prostatectomy. Out of 24 pts reporting erectile ability before surgery, 10 was in B1 stage and underwent monolateral nerve-sparing technique. Out of these, 6 pts (60%) maintained the erection after the operation. The treatment with LHRH analogues weighted on loss of libido and erectile and erectile potent due to central androgenic delete. At our Institute 87 pts in treatment with LHRH analogues reported loss of erection in 80% of cases. In this group 22 underwent to an andrological examination. The exams (Dynamic penile Doppler, Dynamic Cavernosometry and stimulating test with intracavernous vasoactive drugs) confirm the absence of peripherical damages in the pathogenesis of the erectile dysfunction. Patient underwent radiotherapy develop a secondary impotence due to an obliterant progressive angioitis in a percentage ranging from 30 to 80%.(ABSTRACT TRUNCATED AT 250 WORDS)

Erectile Dysfunction↗

PubMed1993

Bulbocavernous myocutaneous flap: a new technique in repair of recurrent urethrovaginal fistula.

This paper describes the case of a recurrent post-partum urethrovaginal fistula. The extent of the vaginal tissues loss and the perilesional scarring made the direct closure of the defect non practicable. After suturing the urethra, the anterior vaginal wall was reconstructed with an island bulbocavernous musculocutaneous flap raised from the left labium majus. Nineteen months after surgery the flap healed well without peri urethral suffusion.

Adult↗

PubMed1993

Our treatment of congenital complicated penile deviations.

Congenital anomalies of the penis expressed in various forms of flexures can be associated to a rotation of the shaft. An asymmetrical insertion of the suspensory ligament on the dorsal surface of the tunica albuginea often accounts for corporal rotation. This distorts the spatial relationship between the corpora cavernosa and the pubic bone. The two corpora may overlap and the shaft is partially rotated. For the surgical treatment of these defects we proposed (1989) a technique of contrarotation of the tunica albuginea which was later abandoned because it was too invasive. We developed a technique based on the ipsilateral re-suspension of the suspensory ligament of the penis between the tunica of the lower corpus and the pubic symphysis to restore the true axis. The neurovascular adnexa, the corpora cavernosa, and the corpus spongiosum remain untouched.

Follow-Up Studies↗

PubMed1993

[Seminal changes of inflammatory origin].

Presence of bacteria in the sperm is often associated to a reduction of fertility in relationship with a decrease in number and motility of spermatozoa and with an augmentation of the abnormal spermatic cells. Clinical features of seminal phlogosis are extremely variable both in acute and chronic evolutions. In every case the first diagnostical step is sperm count and seminal complete analysis which can give evidence of phlogistic alteration in quantity and quality of spermatic cells with a typical presence of an excess in white blood cells (leucospermia) as consequence of infection. The great variety in clinical and bacteriological aspects and the particular biological features of the organs involved, as the prostate, make treatment a difficult problem to solve with particular regard to the choice of an effective antibiotic which pharmacokinetic has to result suitable for the microorganism as well as for the tissue of the infection site. All those efforts are indispensable to reduce the too frequent therapeutical failures in the management of seminal phlogistic pathology with complications of organic but also pathological relevancy for the patient and the partner too.

Anti-Bacterial Agents↗

PubMed1993

Measurement of regional cerebral glucose utilization with fluorine-18-FDG and PET in heterogeneous tissues: theoretical considerations and practical procedure.

Functional tissue heterogeneity, i.e., inclusion of tissues with different rates of blood flow and metabolism within a single region of interest, is an unavoidable problem with PET. Errors in determination of regional cerebral glucose utilization (rCMRglc) with [18F]FDG have resulted from the currently used simplifying assumption that all regions examined are homogeneous. We have established an optimal, yet practical procedure to minimize errors due to tissue heterogeneity in determination of rCMRglc. Effects of applying the three-rate constant kinetic model designed for homogeneous tissues with both dynamic and single-scan procedures and the Patlak plot were evaluated in normal subjects in experimental periods up to 120 min following tracer injection. The procedure with a single scan carried out any time within the interval between 60 and 120 min following tracer injection, combined with population average rate constants determined over a 120-min period, was found to be optimal for quantitative rCMRglc studies.

Adult↗