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At least 19 recordsLinked to original sources
PubMed1983

The use of stereotaxic chemical hypophysectomy in the treatment of thalamic pain syndrome.

Three patients with neurological injuries consistent with cerebral stroke subsequently developed pain over portions of the body contralateral to the injured hemisphere. Stereotaxic chemical hypophysectomy was used in the management of this pain after other surgical procedures and medical management had failed to provide relief. Postoperatively, all patients were treated for hypopituitarism. All developed transient diabetes insipidus, and one patient developed transient right third nerve palsy. No other complications were encountered. All three patients experienced significant pain relief within 48 hours of the procedure. By the date of discharge, two of the three patients reported complete, and the third greater than 80% pain relief. At the initial follow-up visit all patients were essentially pain-free. These patients have now been followed for 58, 39 and 19 months, and remain free of their original pain. During this time the intravenous administration of naloxone has failed to reproduce the preoperative pain. Pituitary function testing 1 year or more following operation demonstrated that none of the patients had an endocrinologically complete hypophysectomy. Recovery from transient diabetes insipidus was not associated with return of the original pain. The mechanism of action of stereotaxic chemical hypophysectomy in the relief of pain related to thalamic lesions remains unknown. The observation that naloxone failed to reproduce the preoperative pain casts doubt on the theory that augmentation of endogenous opiate release is the primary mechanism. Additional observations suggest that pain relief after hypophysectomy may be more directly the result of stimulation of a hypothalamic pain-suppressing mechanism than due to the elimination of pituitary hormones.

Aged↗
PubMed1980

[Peroperative hyperthermia in chemical hypophysectomies].

In this work the Authors enunciate various physiopathogenetic hypotheses about malignant hyperthermia occurring in general anaesthesia for chemical-hypophysectomy: serotoninergic system would induce malignant hyperpyrexia? This is the most probable hypothesis.

Body Temperature Regulation↗
PubMed1978

Chemical hypophysectomy for relief of bone pain in carcinoma of the prostate.

A series is presented of 10 patients with intractable pain secondary to diffuse metastatic prostatic carcinoma. These patients underwent pituitary ablation by a new method of chemical hypophysectomy, which consisted of multiple injections of absolute alcohol into the pituitary gland under stereotaxic control. Of the 10 patients 9 had good to excellent pain relief. There was no operative mortality. The sequelae are those associated with pituitary destruction, the most significant being diabetes insipidus. Preoperative and postoperative hormonal studies failed to reveal any significant hormonal changes despite good and almost immediate pain relief.

Diabetes Insipidus↗
PubMed1980

Treatment of pain of diffuse metastatic cancer by stereotactic chemical hypophysectomy: long term results and observations on mechanism of action.

Stereotactic instillation of absolute alcohol into the sella turcica for pituitary destruction was carried out in 29 patients divided into two groups. Seventeen with prostatic carcinoma underwent a total of 19 injections with 94% good to excellent results that persisted throughout the remainder of the patient's life-span. The longest survival was 9 months. Brief relapses did occur, but spontaneous remissions were the rule. A second group of mixed cancers contained 12 patients who received a total of 13 injections. Eleven patients had good to excellent results that persisted in all but 1 patient. The longest survival was 7 months. Hormonal levels and prolactin stimulation tests failed to show any correlation between hormonal changes and pain relief. Naloxone reversal of analgesia did not occur. There was no loss of cognitive function shown on psychological testing. Pathological studies showed destruction of the pituitary gland, which was subtotal in some patients despite good pain relief. All examinations showed that the pituitary stalk was destroyed. Patients who survived longer also showed degeneration of the supraoptic and paraventricular nuclei of the hypothalamus and the median eminence. All but 1 patient with pain relief exhibited a lack of antidiuretic hormone (ADH) production. Interpretation of the data indicates that ADH or its associated neurophysins act as central pain transmitters. The production of these transmitters is decreased or abolished by chemical hypophysectomy through the destruction of hypothalamic nuclei.

Cognition↗
PubMed1984

Pain relief after hypophysectomy.

Thirteen series of patients who underwent surgical or chemical hypophysectomy for the relief of pain associated with cancer were reviewed. In 10 series, involving 334 patients with breast or prostate cancer, surgical hypophysectomy produced pain relief in 70% of the patients afflicted with either tumor, including some with no evidence of hormone dependence. These results were then compared with the results of chemical hypophysectomy. This procedure was performed in 3 series involving 533 patients, of whom 24% had cancer other than breast or prostate. Chemical hypophysectomy produced pain relief in over 75% of the patients, regardless of tumor type or hormonal dependence. The possible role of the pituitary, the hypothalamus, and endogenous opiates in mediating the pain relief associated with hypophysectomy was examined. The mechanism by which pain relief is achieved remains unclear, but there is significant evidence that this relief is not related directly to the expected fall in the levels of known pituitary hormones. Evidence is provided that pain relief is the result of a hypothalamic pain-suppressing capability triggered by hypophysectomy. On the basis of both clinical data and the mechanism of action, we conclude that surgical and chemical hypophysectomy are fundamentally similar procedures.

Breast Neoplasms↗
PubMed1986

Evidence for the involvement of cerebral renin-angiotensin system (RAS) in stress analgesia.

Studies concerning variations of the central renin-angiotensin system (RAS) during immobilization stress in rats have shown a significant increase in renin-like activity in the hypothalamus and fronto-parietal cortex, together with a definite decrease in the hypophysis and pineal gland. The resultant stress analgesia is blocked by the previous administration of naloxone and saralasin (angiotensin II antagonist). The intracerebral administration of renin and angiotensin II produces an increase in latencies to thermoalgesic stimuli; this is reduced, as is immobilization stress, by naloxone and saralasin. Both chemical hypophysectomy obtained by dexamethasone pretreatment as well as surgical epiphysectomy block the stress-induced analgesia. The experimental data obtained argue in favour of the participation of the cerebral RAS in stress analgesia through the indirect mechanism of release of opioid peptides.

Analgesia↗
PubMed1997

Alterations in follicular maturation associated with within-breed variation in ovulation rate in Chios sheep.

Within-breed comparisons may be helpful to identify, in a given genetic background (Chios sheep), ovarian strategies and control mechanisms associated with altered ovulation rate. High and low ewes were identified from two large groups (n = 27 and n = 33 in Exp. 1 and Exp. 2 respectively) of Chios ewes submitted to repeated laparoscopies (24 times in Exp. 1 and six times in Exp. 2). High ovulatory ewes (n = 6 and n = 7 in Exp. 1 and Exp. 2 respectively) had mean ovulation rates of 4.3 (Exp. 1) and 4.2 (Exp. 2) while low ovulatory ewes (n = 6 and n = 7 in Exp. 1 and Exp. 2 respectively) had mean ovulation rates of 2.5 (Exp. 1) and 1.9 (Exp. 2). In Exp. 1, follicular function was compared in these two groups of ewes using follicles obtained at 30 h following luteolysis in the same ewes before and after unilateral ovariectomy (ULO). In Exp. 2, circulating follicle stimulating hormone (FSH) concentrations were measured from the end of the luteal phase up to the preovulatory surge in high and low ewes. Thereafter, to demonstrate a causal link between high FSH and high ovulation rate, pituitary downregulation was achieved by a 17-day gonadotrophin releasing hormone (GnRH) agonist treatment and the ovarian response to similar amounts of exogenous gonadotrophins compared between high and low ewes. Numbers of oestrogenic (in vitro oestradiol > 250 pg ml-1 h-1) follicles on the first ovary removed (Exp. 1) were 2.16 +/- 0.5 vs. 1.33 +/- 0.17 in high and low ewes (P = 0.1). Following ULO, these numbers were 3.33 +/- 0.33 and 2.5 +/- 0.18 (P < 0.05 between high and low ewes). There were no significant differences between the first and second ovaries for any of the parameters studied. Follicles from high ovulatory ewes (n = 33) differed from those of low ovulatory ewes (n = 23) by a smaller size (P < 0.01), a reduced number of granulosa cells (P < 0.01) together with decreased oestradiol (P < 0.05) and testosterone (P < 0.01) production in vitro. However, steroid production per cell (oestradiol per granulosa cell, testosterone per thecal cell) was similar in the two groups of sheep. FSH concentrations (Exp. 2) in high ovulatory ewes were significantly higher than those of low ovulatory ewes during the late luteal phase, and the decrease in FSH concentrations was steeper (1.4 ng) during the early follicular phase for high ovulatory ewes than low ovulatory ewes. Chemical hypophysectomy achieved by a 17-day treatment with a GnRH agonist demonstrated that these high FSH concentrations may be important to generate the high ovulation rate of the 'high' ewes as ovulation rate of high and low ewes was similar following chemical hypophysectomy followed by administration of similar amounts of exogenous gonadotropins to both groups of ewes. It is concluded that, despite different genetic control of their high ovulation rate (Chios-polygenic; Booroola-major gene), alterations in follicular function and its control are very similar in high ovulatory Chios and in FecB carriers.

Analysis of Variance↗
PubMed2003

Role of pituitary radiosurgery for the management of intractable pain and potential future applications.

RATIONALE: Two or three decades ago, cancer pain was treated by surgical/chemical hypophysectomy. In one report, the control of central pain (thalamic pain syndrome) was also approached with chemical hypophysectomy. Although in most of the patients these treatments resulted in a decrease in severe pain, concomitantly severe adverse effects (panhypopituitarism, diabetes insipidus and visual dysfunction) occurred in most patients. This historical evidence prompted us to perform Gamma Knife surgery (GKS) for this kind of intractable severe pain using a high irradiation dose to the pituitary stalk/gland. In the majority of patients, marked pain relief was achieved, surprisingly without any of the complications mentioned above. MATERIALS AND METHODS: A prospective multicenter study was conducted to evaluate the efficacy and safety in patients treated in Prague, Hong Kong and Tokyo. Indications of this treatment were: (1) failure of other effective treatment approaches prior to GKS, (2) good general patient condition (Karnofsky performance status >40%), (3) response to morphine for pain control (cancer pain), and (4) no previous radiotherapy of brain metastases (GKS/conventional radiotherapy). Eight patients with severe cancer pain due to bone metastasis and 12 patients with post-stroke thalamic pain syndrome were treated with GKS. The target was the border between the pituitary stalk and gland. Maximum dose was 160 Gy for cancer pain and 140 Gy for central pain. Follow-up included 6 patients (>1 month) with cancer pain and 8 patients (> 6 months) with thalamic pain syndrome. RESULTS: All patients (6/6) with cancer pain experienced significant pain reduction, and 87.5% (7/8) of the patients with thalamic pain had initially significant pain reduction. In some patients, pain reduction was delayed for several hours. Pain relief was noted within 7 days (median 2 days). No recurrence was observed in the patients with cancer pain. However, in 71.4% (5/7) of the patients with thalamic pain syndrome, disease recurred during the 6-month follow-up. Up to now, other complications have not been observed. CONCLUSION: Our clinical study protocol is only preliminary. Further clinical results on the management of thalamic pain are required to develop this treatment protocol. However, efficacy and safety have been shown in all our cases. In our opinion, this treatment has a potential to control severe pain, and GKS will play an important role in the management of intractable pain.

Bone Neoplasms↗
PubMed1986

Androgen metabolism in the human epididymis. Effect of in vivo estrogen administration.

Androgen metabolism in human epididymis was studied by incubating tissue fragments with isotopically labeled testosterone (T) and androstenedione (A) under batch and superfusion conditions. Epididymides were obtained from 16 patients with prostatic cancer, 5 of them treated with diethylstilbestrol (2.5 mg/d) for several months prior to castration. Results from batch incubations with [3H]T (100 nM) for 2 h at 25 degrees C indicated a markedly lower 5 alpha-reductase activity in tissues from estrogen-treated patients, as evaluated by measuring the amounts of radioactive 5 alpha-dihydrotestosterone, 5 alpha-androstanediols and 5 alpha-androstanedione present in tissue and medium at the end of the incubation period. Superfusion experiments confirmed this estrogen effect and also showed a shift of the interconversion between A and T towards the reductive direction and a diminished tissue retention of DHT after estrogen treatment. These effects may contribute to the marked regression of the epididymal epithelium that was noted in the estrogen-treated patients, which is thought to be mainly the result of the inhibition of androgen biosynthesis caused by chemical hypophysectomy.

Aged↗
PubMed1977

Treatment of diffuse metastatic cancer pain by instillation of alcohol into the sella turcica.

The technique of "chemical hypophysectomy" was modified for the management of pain due to metastatic cancer. Using stereotaxic control, a needle is introduced via the nose into the sella turcica. Absolute alcohol is then injected into the pituitary. Of 13 patients who had severe uncontrollable pain, 11 obtained marked symptomatic relief. The longest follow-up period to date is seven months, with results persisting. Sequelae are those associated with destruction of the pituitary gland, the most significant being diabetes insipidus. Several cerebrospinal fluid leaks prompted us routinely to instill alpha-ethyl cyanoacrylate to seal the sella floor. Three patients had slight extraocular nerve palsies. There was no death related to the procedure.

Anesthesia, Spinal↗
PubMed2005

Gamma knife surgery of the pituitary: new treatment for thalamic pain syndrome.

OBJECT: Although reports in the literature indicate that thalamic pain syndrome can be controlled with chemical hypophysectomy, this procedure is associated with transient diabetes insipidus. It was considered reasonable to attempt gamma knife surgery (GKS) to the pituitary gland to control thalamic pain. METHODS: Inclusion criteria in this study were poststroke thalamic pain, failure of all other treatments, intolerance to general anesthetic, and the main complaint of pain and not numbness. Seventeen patients met these criteria and were treated with GKS to the pituitary. The target was the pituitary gland together with the border between the pituitary stalk and the gland. The maximum dose was 140 to 180 Gy. All patients were followed for more than 3 months. CONCLUSIONS: An initial significant pain reduction was observed in 13 (76.5%) of 17 patients. Some patients experienced pain reduction within 48 hours of treatment. Persistent pain relief for more than 1 year was observed in five (38.5%) of 13 patients. Rapid recurrence of pain in fewer than 3 months was observed in four (30.8%) of 13 patients. The only complication was transient diabetes insipidus in one patient. It would seem that GKS of the pituitary might have a role to play in thalamic pain arising after a stroke.

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