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Biomedical subjects

I Karacan

Publications and source records attributed to I Karacan.

At least 37 records · Page 2Linked to original sources
PubMed1989

Hypertension, erectile dysfunction, and occult sleep apnea.

Sleep-related respiratory pattern was evaluated in 175 hypertensive and 110 normotensive men, none of whom reported difficulties in initiating or maintaining sleep. Patients were grouped according to sexual status (complaint of erectile problems), hypertension treatment status (treated or untreated), and blood pressure (diastolic less than 90 or greater than or equal to 90). The prevalence of sleep apnea, apnea index, duration of the longest episode of apnea, and penile rigidity were tabulated. The group with elevated blood pressure, persistent even with antihypertensive drug therapy, had the most sleep apnea. The treated hypertensive men with controlled blood pressure had significantly less apnea than those whose blood pressure remained high. Untreated hypertensive groups, however, did not differ from normotensive groups with respect to apnea. Evidence of abnormal sleep-related respiratory activity was found in both hypertensive and normotensive groups with erectile problems. Interestingly, penile rigidity was significantly lower for hypertensive men with erectile complaints than for normotensive men with erectile complaints. There was also a small, but significant, negative correlation between apnea index and penile rigidity among men with erectile complaints. These results indicate that sexual status is an important consideration in the diagnosis of hypertension and sleep apnea. Moreover, these data suggest an interrelationship among hypertension, erectile dysfunction, and sleep apnea.

Antihypertensive Agents↗
PubMed1987

Cerebral blood flow in normal and abnormal sleep and dreaming.

Measurements of regional or local cerebral blood flow (CBF) by the xenon-133 inhalation method and stable xenon computerized tomography CBF (CTCBF) method were made during relaxed wakefulness and different stages of REM and non-REM sleep in normal age-matched volunteers, narcoleptics, and sleep apneics. In the awake state, CBF values were reduced in both narcoleptics and sleep apneics in the brainstem and cerebellar regions. During sleep onset, whether REM or stage I-II, CBF values were paradoxically increased in narcoleptics but decreased severely in sleep apneics, while in normal volunteers they became diffusely but more moderately decreased. In REM sleep and dreaming CBF values greatly increased, particularly in right temporo-parietal regions in subjects experiencing both visual and auditory dreaming.

Adult↗
PubMed1987

Bulbocavernosus reflex to somatic and visceral nerve stimulation in normal subjects and in diabetics with erectile impotence.

Bulbocavernosus reflex to stimulation of the vesicourethral junction and glans penis was recorded in 14 normal controls and 24 diabetic men complaining of erectile impotence. In all normal subjects the bulbocavernosus reflex to stimulation of these sites could be obtained, and mean latencies were 59.2 +/- 8.0 msec. and 33.3 +/- 3.7 msec., respectively (p less than 0.00001). A total of 66 per cent of the diabetics (16 patients) exhibited abnormal (delayed or absent) bulbocavernosus reflex to stimulation of the vesicourethral junction, while only 12.5 per cent (3 patients) had delayed response to glans penis stimulation. The latter tended to remain within normal limits, although the mean latency was significantly different from that of normal subjects (p less than 0.05). Abnormalities of the bulbocavernosus reflex to stimulation of the vesicourethral junction correlated strongly with the presence of peripheral and autonomic neuropathy, diabetes and organogenic impotence. Our results indicate that this is an informative test for the evaluation of visceral afferents arising from the bladder neck and, hence, in the differential diagnosis of organogenic versus psychogenic erectile impotence.

Adult↗
PubMed1987

Penile blood flow and musculovascular events during sleep-related erections of middle-aged men.

The relationships among penile segmental pulsatile blood flow, pelvic musculovascular events, phases of nocturnal penile tumescence, and sleep stages were studied by all-night polysomnography in 23 healthy middle-aged men. Penile blood flow peaked during maximal tumescence. Bursts of phasic musculovascular activity were more frequent during ascending and maximal tumescence than during detumescence and baseline. Both penile blood flow and the number of musculovascular events increased during REM sleep. These data describe important local aspects of penile erectile mechanisms in normal men. The findings on musculovascular events support the notion that the bulbocavernosus-ischiocavernosus muscles have a role in human penile erection.

Adult↗
PubMed1986

Inflatable and noninflatable penile prostheses: comparative follow-up evaluation.

This evaluation was conducted with 63 men who were organically impotent and subsequently received either an inflatable penile prosthesis (n = 43), a noninflatable penile prosthesis (n = 14), or both in succession (n = 6). The patient groups were compared for sexual satisfaction, sexual activity, mental status, complications, satisfaction with prosthesis, and relationship changes. The methods of evaluation were the Derogatis Sexual Functioning Inventory and two unstandardized questionnaires. Significant differences were found between the two patient groups: inflatable prosthesis recipients report being more sexually satisfied, more satisfied with their implant, experiencing less psychiatric distress, having a more rapid postsurgical recovery, more sexually active, and experiencing more positive changes in relationships with their partners than do recipients of a noninflatable prosthesis. The data suggest that the inflatable prosthesis may be a more favorable choice for most individuals than noninflatable devices.

Adaptation, Psychological↗
PubMed1986

Cerebral responses evoked by stimulation of the vesico-urethral junction in normal subjects.

Following bipolar stimulation of the vesico-urethral junction (VUJ), evoked potentials (EPs) with a late and prominent negativity (mean latency 91.4 +/- 11.0 msec) were recorded from scalp in 22 male subjects. Although remarkable intersubject variations occurred, no peak variation could be seen in any given subject. Maximum amplitude of the EPs was recorded from Cz and CzP points. Stimuli with various frequencies did not lead to any differences in shape and latency of EPs. The differences between the EPs by bipolar stimulation of the VUJ and the responses elicited by distal urethral and pudendal nerve stimulation suggest that, during bipolar stimulation of VUJ, the somatic afferents were not excited. Therefore, these responses were most likely due to the excitement of the visceral afferents arising from the VUJ separately. This method may be a useful technique for evaluating the physiological condition of the afferent nerves arising from VUJ.

Adult↗
PubMed1986

Cerebral responses evoked by stimulation of vesico-urethral junction in man: methodological evaluation of monopolar stimulation.

Cerebral responses after bipolar stimulation (BpS) and monopolar stimulation (MpS) of the vesico-urethral junction (VUJ), as well as skin surface stimulation of various hip and pelvic structures, were recorded in 13 normal control subjects. BpS of VUJ produced cerebral evoked potentials (CEPs) with a negative peak (mean latency 88.69 +/- 13.73 msec) following a smaller positive deflection, while MpS of the same sites with indifferent electrodes placed on various pelvic or hip structures resulted in different response latencies that were all significantly shorter than those of BpS. Shape and latency of responses after MpS of VUJ were similar to those elicited by skin surface stimulation of the abdominal wall and the iliac crest; those elicited by pudendal nerve stimulation at the glans were also similar in shape but significantly greater in latency. Results strongly indicate that during MpS of VUJ the somatic or muscle afferents located in the hip and pelvic region are stimulated; consequently, BpS technique should be considered the preferred technique for investigating the physiological condition of visceral afferents arising from VUJ.

Adult↗
PubMed1986

Erectile dysfunction in narcoleptic patients.

Many male narcoleptic patients complain of erectile dysfunction related to chemotherapy, and some find it so distressing that they fail to continue treatments. This is a potentially dangerous situation. We studied the erectile capabilities of 28 narcoleptic men who had complaints of erectile dysfunction with our objective sleep laboratory measurement of nocturnal penile tumescence (NPT) for diagnostic workup. We found that while short REM latency, a classic indicator of narcolepsy, was present in all patients, NPT, which is associated with REM sleep, did not coincide with the short REM latencies in about half the patients. This may be partially due to the fact that first-cycle REM is often not accompanied by NPT episodes (even in the control population). We also found that, in a few cases, the patients' subjective beliefs about their erectile capacity tended to underestimate our measurements. The patients receiving drug treatment already had some vasculogenic or neurogenic genital impairment, which probably made them more vulnerable to the effects of the drugs. Patients who had none of these complications showed similar erectile impairment under the influence of medication. Additionally, we found unique manifestations of the disease in three drug-free patients; one had cataplectic attacks upon arousal, and two had unexplained erectile impairment.

Adult↗
PubMed1986

Uterine activity during sleep.

REM-related increases in uterine activity were found in 10 healthy young adult volunteer subjects. Contraction baseline pressures were elevated compared with NREM sleep, stage 2 sleep, stages 3 and 4 slow wave sleep (SWS), and stage 0. Contraction amplitudes during REM sleep were greater than those during SWS and stage 0, while contraction rates differed only between REM sleep and SWS. The results strongly indicated a cycle of genital activity in women that parallels the penile erection cycle in men. The implications of this finding and suggestions for future research are discussed.

Adult↗
PubMed1985

Sleep patterns of sober chronic alcoholics.

The somnopolygraphs of 26 sober chronic alcoholics were compared with those of an age-matched control group, after approximately 25 days of sobriety. The sleep efficiency index and latency to sleep onset were significantly disturbed in alcoholic subjects. There was a decrease in the number of REM episodes. Slow-wave sleep was unaffected except for an increase in the latency to stge 4 sleep. These findings are discussed in the light of previous research.

Adult↗
PubMed1985

Recent developments in the diagnosis and treatment of sleep disorders.

The publication of a new nosology of sleep and arousal disorders in 1979 established the need for differential diagnosis of sleep disorders based on polysomnographic evaluations as well as medical history and physical examination. This review of recent developments in diagnosing and treating sleep disorders covers such topics as prevalence, findings related to sleeping pills and insomnia, effects of depression on sleep, and managing the elderly patient with disturbed sleep. The authors caution against misuse of hypnotic drug therapy for treatment of insomnia and encourage physicians to inquire about sleep patterns even when a patient is presenting a seemingly unrelated problem.

Aged↗
PubMed1984

Women's satisfaction with partners' penile implant. Inflatable vs noninflatable prosthesis.

We evaluated 49 women whose sexual partners were organically impotent and subsequently received either an inflatable or noninflatable penile prosthesis. The women comprised three groups, based on the type of prostheses their partners had received: inflatable (n = 34), noninflatable (n = 11), and a double implant group (n = 4). The comparisons made were (1) dimensions of sexual satisfaction, (2) emotional stability, (3) satisfaction with the prosthesis, and (4) relationship changes. Two special questionnaires and the Derogatis Sexual Functioning Inventory were utilized in this evaluation. Women in the inflatable prosthesis group were found to be significantly more satisfied with the quality of their sexual relations and with their partner's prosthesis than were the women in the noninflatable prosthesis group. There apparently is a general advantage to women whose partners have received an inflatable prosthesis compared with the noninflatable alternatives.

Adult↗
PubMed1984

Symptomatology, evaluation and treatment of aquaductal stenosis.

Thirty-three surgical treated cases of aquaductal stenosis are presented. Beside the classical clinical representation of the disease, the symptomatology caused by anterior and posterior herniation of dilated third ventricle is discussed. The impotence in one male patient which is caused by anterior herniation was proved by means of NPT (Nocturnal Penile Tumescence) recording. In one patient bilateral partial deafness and Parinaud syndrome which was caused by posterior herniation was cured by third ventriculostomy. In the surgical treatment of aquaductal stenosis, the effectiveness of various surgical procedures are presented and the superiority of third ventriculostomy by microtechnique is emphasised.

Adolescent↗
PubMed1984

Sleep-related electrodermal activity patterns in impotent patients.

The etiology of erectile failure is not always clear despite the fact that recordings of nocturnal penile tumescence (NPT) are used to detect patients with a significant organic component to their complaint. We recorded electrodermal activity in addition to NPT in 60 impotent patients. Normally more electrodermal activity occurs in stage 2 than in stage REM sleep. Despite a similar total amount of electrodermal activity, organically impotent patients tended to have less electrodermal activity in stage 2 and more in stage REM sleep than those with normal NPT. This difference was due to a subgroup of 15 organically impotent patients with less electrodermal activity in stage 2 than in stage REM sleep. Because of this difference in the pattern of electrodermal activity in relation to sleep stages, the results suggest a central nervous system change is related to impaired erectile capability and abnormal NPT in these cases.

Adult↗
PubMed1983

Erectile mechanisms in man.

Increases in penile circumference during sleep-related erections in human subjects closely reflected increases in penile blood flow, and bursts of activity in the bulbocavernosus and ischiocavernosus muscles were temporally related to these increases. The penile arterial system and the perineal muscles appear to have important coordinated roles in human penile erection. Monitoring sleep-related erections and penile blood flow holds promise for the study of erectile mechanisms and dysfunction and for screening of drugs.

Adult↗
PubMed1983

Reactions to the implantation of an inflatable penile prosthesis among psychogenically and organically impotent men.

We evaluated 17 nondepressed and psychologically stable recipients of an inflatable penile prosthesis who had been either organically or psychogenically impotent and 12 of their sexual partners several months after surgical implantation. The men were evaluated for changes in general psychological adjustment, sexual satisfaction and sexual activity. The partners were assessed separately on similar instruments. Two scales of the Minnesota Multiphasic Personality Inventory were found to have potential for initially discriminating organic and psychogenic impotence. The hypothesis that psychogenic recipients would manifest more psychological difficulties and would be less satisfied was only partially supported. While neither group suffered significant disturbance in psychological adjustment a consistent pattern was noted in which psychogenic patients were somewhat less satisfied with the results and experienced more postoperative complications. However, over-all reactions were positive, including increases in frequency of sexual over-all reactions were positive, including increases in frequency of sexual intercourse and duration of sexual play for patients and their partners.

Coitus↗
PubMed1983

Plasma growth hormone during sleep in young and aged men.

Plasma growth hormone measured at 20-min intervals across the night via indwelling venous cannula revealed a significant reduction in 16 healthy aged men as compared with 14 healthy young men. The decrease in growth hormone was entirely confined to the first 3 hours of the night (M +/- SEM for the integrated level was 5.0 +/- 1.2 and 21 +/- 4.2 ng . hr/ml). Growth hormone across the latter part of the night did not differ. Day and evening growth hormone levels measured hourly in five of the aged and nine of the young men failed to reveal an age effect. Growth hormone release is known to be associated with sleep onset, and particularly with slow wave sleep, stage 3 and 4, which was reduced in amount in these aged men (9.9 +/- 1.9 and 22.8 +/- 2.3% of time in bed for aged and young groups, respectively). Sleep stage 3 and 4 correlated significantly with growth hormone level (R = .463, p less than .01) for young and aged men combined, but not for either age group alone, indicating that growth hormone does not have a direct, simple relationship with slow wave sleep.

Adult↗