The amount of compensatory sweating depends on the patient, the damage that the white rami communicans incurs, and the amount of cell body reorganization in the spinal cord after surgery.
Other potential complications include inadequate resection of the ganglia, gustatory sweating, pneumothorax, cardiac dysfunction, post-operative pain, and finally Horner’s syndrome secondary to resection of the stellate ganglion.
www.ubcmj.com/pdf/ubcmj_2_1_2010_24-29.pdf

After severing the cervical sympathetic trunk, the cells of the cervical sympathetic ganglion undergo transneuronic degeneration
After severing the sympathetic trunk, the cells of its origin undergo complete disintegration within a year.
http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0442.1967.tb00255.x/abstract

Spinal cord infarction occurring during thoraco-lumbar sympathectomy
J Neurol Neurosurg Psychiatry 1963;26:418-421 doi:10.1136/jnnp.26.5.418

Saturday, May 26, 2012

75% pneumothorax expected after sympathectomy

A small insignificant pneumothorax can be expected after ETS in about 75% of cases [15], which gets spontaneously absorbed, usually within 24 h.

Comparing T2 and T2–T3 ablation in thoracoscopic sympathectomy for palmar hyperhidrosis: a randomized control trial
A. N. Katara, J. P. Domino, W.-K. Cheah, J. B. So, C. Ning, D. Lomanto
Minimally Invasive Surgical Centre, Department of General Surgery, National University Hospital, 5 Lower Kent Ridge Road, Singapore, 119074
Received: 13 October 2006/Accepted: 2 November 2006
http://medicine.nus.edu.sg/medsur/research_publications_2007.html

Permanent side effects included compensatory sweating in 67.4%, gustatory sweating in 50.7% and Horner's trias in 2.5%. However, patient satisfaction declined over time, although only 1.5% recurred. This left only 66.7% satisfied, and a 26.7% partially satisfied. Compensatory and gustatory sweating were the most frequently stated reasons for dissatisfaction. Individuals operated for axillary hyperhidrosis without palmar involvement were significantly less satisfied (33.3% and 46.2%, respectively).
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1234291/

Monday, May 21, 2012

sympathectomy improves skin blood flow at the thermoregulatory but not the nutritive level of skin microcirculation

sympathectomy improves skin blood flow at the thermoregulatory but not the nutritive level of skin microcirculation. This may be related to the fact that the thermoregulatory vessels are mainly sympathetically controlled, whereas the nutritive capillaries are mainly controlled by local (nonneural) factors.
http://www.springerlink.com/content/ukwtrn2y72age93t/

Depending on the series and the duration of follow-up, the success rate of sympathectomy varies from 12% to 97%

http://www.ispub.com/journal/the-internet-journal-of-pain-symptom-control-and-palliative-care/volume-2-number-1/complex-regional-pain-syndrome-a-clinical-review.html

Sunday, May 20, 2012

typical CRPS changes also occur following sympathectomy, which has traditionally been considered curative of CRPS

(p.557)

Handbook of Neurosurgery

Mark S. Greenberg

Thieme, 22/02/2010 - 1352 pages

For two decades, Handbook of Neurosurgery -- now in a fully updated seventh edition -- has been an invaluable companion for every neurosurgery resident and nurse, as well as neurologists and others involved in the care of patients with brain and spine disorders.

Sympathectomy has been discredited in this condition

Vasospastic conditions

Raynaud’s syndrome

http://surgeryonline.wordpress.com/category/arterial-disorders/

Drug warning - Karvezide, AVAPRO HCT - 'you must tell your doctor if you have had sympathectomy'

Tell your doctor if:

* you have had a sympathectomy

* you have been taking diuretics

*you have a history of allergy or asthma

www.racgp.org.au/cmi/swckarvz.pdf

2. Before you start to take AVAPRO HCT

Tell your doctor if:

you suffer from any medical conditions especially-
- kidney problems, or have had a kidney transplant or dialysis
- heart problems
- liver problems, or have had liver problems in the past
- diabetes
- gout or have had gout in the past
- lupus erythematosus
- high or low levels of potassium or sodium or other electrolytes in your blood
- primary aldosteronism
you are strictly restricting your salt intake
you are lactose intolerant or have had any allergies to any other medicine or any other substances, such as foods, preservatives or dyes.
have had a sympathectomy
you have been taking diuretics
you have a history of allergy or asthma

http://www.mydr.com.au/medicines/cmis/avapro-hct-300-25-tablets

Published by MIMS/myDr March 2011

UBM Medica Australia uses its best endeavours to ensure that at the time of publishing, as indicated on the publishing date for each resource (e.g. Published by MIMS/myDr January 2007), the CMI provided was complete to the best of UBM Medica Australia's knowledge.

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sympathectomy interrupts neural messages to many different organs, glands and muscles

Surgical and chemical sympathectomy can alter cellular proliferation

Surgical denervation and chemical sympathectomy can alter cellular proliferation, B- and T-cell responsiveness and lymphocyte migration in lymphoid organs [17].

In vitro studies have shown that neuropeptides can have numerous effects, either inhibiting or stimulating the proliferation, differentiation and functions of immune cells [19]* Development of systemic lupus erythematosus in mice is associated with alteration of neuropeptide concentrations in inﬂamed kidneys and immunoregulatory organs

Neuroscience Letters 248 (1998) 97– 100

sympathectomy affects the heart, sweating, and circulation

heart rate was significantly reduced at rest (14%), at sub-maximal exercise (12.3%), and at peak exercise (5.7%), together with a significant increase in oxygen pulse (11.8, 12.7, and 7.8%, respectively). The rate pressure product (RPP) was also significantly reduced following the surgical procedure at all three study stages, while all other physiological variables measured remained unchanged. It is suggested that thoracic-sympathetic denervation affects the heart, sweating, and circulation of the respective denervated region

Eur J Appl Physiol. 2008 Sep;104(1):79-86. Epub 2008 Jun 10.

sympathectomy affects the heart, sweating, and circulation

Acquired cardiovascular disease following Sympathectomy

We found statistically significant differences (P < .05) in both time and frequency domains. Parameters that evaluate global cardiac autonomic activity (total power, SD of normal R-R intervals, SD of average normal R-R intervals) and vagal activity (rhythm corresponding to percentage of normal R-R intervals with cycle greater than 50 ms relative to previous interval, square root of mean squared differences of successive normal R-R intervals, high-frequency power, high-frequency power in normalized units) were statistically significantly increased after sympathectomy. Low-frequency power in normalized units, reflecting sympathetic activity, was statistically significantly decreased after sympathectomy. Low-/high-frequency power ratio also showed a significant decrease, indicating relative decrease in sympathetic activity and increase in vagal activity.

The Journal of Thoracic and Cardiovascular Surgery
Volume 137, Issue 3, March 2009, Pages 664-669

decreased conditioning-related activity in insula and amygdala after autonomic denervation

The degree to which perceptual awareness of threat stimuli and bodily states of arousal modulates neural activity associated with fear conditioning is unknown. We used functional magnetic neuroimaging (fMRI) to study healthy subjects and patients with peripheral autonomic denervation to examine how the expression of conditioning-related activity is modulated by stimulus awareness and autonomic arousal. In controls, enhanced amygdala activity was evident during conditioning to both "seen" (unmasked) and "unseen" (backward masked) stimuli, whereas insula activity was modulated by perceptual awareness of a threat stimulus. Absent peripheral autonomic arousal, in patients with autonomic denervation, was associated with decreased conditioning-related activity in insula and amygdala. The findings indicate that the expression of conditioning-related neural activity is modulated by both awareness and representations of bodily states of autonomic arousal.

http://www.ncbi.nlm.nih.gov/pubmed/11856537

decline in external heart work due to sympathectomy both at rest and under exercise

DYNAMIC CEREBRAL AUTOREGULATION IS ALTERED BY GANGLION BLOCKADE

After ganglion blockade, systolic and pulse pressure decreased significantly by 13% and 26%, respectively. CBF velocity decreased by 6% (P <0.05). In the very low frequency range (0.02 to 0.07 Hz), mean blood pressure variability decreased significantly (by 82%), while CBF velocity variability persisted. Thus, transfer function gain increased by 81%. In addition, the phase lead of CBF velocity to arterial pressure diminished. These changes in transfer function gain and phase persisted despite restoration of arterial pressure by infusion of phenylephrine and normalization of mean blood pressure variability by oscillatory lower body negative pressure.

Conclusions-: These data suggest that dynamic cerebral autoregulation is altered by ganglion blockade. We speculate that autonomic neural control of the cerebral circulation is tonically active and likely plays a significant role in the regulation of beat-to-beat CBF in humans.

Circulation. 106(14):1814-1820, October 1, 2002.

Hemodynamic changes in vertebral and carotid arteries were observed after sympathicotomy for PH

sympathectomy may constitute malpractice

Referring an anxious patient with palmar hyperhidrosis to surgery may constitute malpractice

"A surgical treatment for anxiety-triggered palmar hyperhidrosis is not unlike treating tearfulness in major depression by severing the nerves to the lacrimal glands."

"Referring an anxious patient with palmar hyperhidrosis to surgery without first completing a proper trial of psychotropic medication may constitute malpractice especially if the patient experiences some of the more severe surgical complications which can occur during sympathectomy" (Bracha et al. 2006 emphasis added)

RESPONSE TO SYMPATHETIC BLOCKADE DEPENDS ON THE DEGREE OF SYMPATHETIC TONE BEFORE THE BLOCK

Denervation of preganglionic cardiac accelerator fibres leaving the cord at T1-T5 results in minimal vasodilatory consequences. Changes however in heart rate, left ventricular function and myocardial oxygen demand may occur due to high thoracic epidural blockade and are discussed below.

The major determinant of heart rate is the balance between sympathetic and parasympathetic systems with the latter predominating. A high thoracic epidural anaesthesia (TEA) covering the cardiac segments (T1-T4) produces small but significant reductions in heart rate4-8. During cardiac sympathetic denervation, parasympathetic cardiovascular responses, including those involved in baroreflexes, may dominate.

Individual cardiovascular response to different levels of sympathetic blockade varies widely, depending on the degree of sympathetic tone before the block.
Anaesth Intensive Care 2000; 28: 620-635
B. T. VEERING*, M. J. COUSINS†
Department of Anesthesiology, Leiden University Medical Center, Leiden, The Netherlands and Department of Anaesthesia and
Pain Management, University of Sydney, Royal North Shore Hospital, Sydney, New South Wales

"sympathectomy ... leads to an increase in the development of tumors on the denervated side"

Effects of upper abdominal sympathectomy on gastric acid, serum gastrin, and catecholamines

Selective upper abdominal sympathectomy increased basal acid output in rats but was without effect on stimulated acid output, serum gastrin concentration, and gastric mucosal histidine decarboxylase activity. The sympathectomy was verified by fluorescence histochemistry and determination of tissue catecholamines. A drastic reduction in tissue noradrenaline, adrenaline, and dopamine levels occurred after sympathectomy, and fluorescence microscopy showed a complete loss of adrenergic nerve fibers. Vagotomy reduced catecholamine levels in the stomach wall by 50% but did not affect the catecholamine content in the pancreas and small bowel. Surprisingly, combined vagotomy and upper abdominal sympathectomy resulted in lower catecholamine levels than sympathectomy alone in extragastric but not in gastric tissues.

http://www.ncbi.nlm.nih.gov/pubmed/6515311

ATELECTASIS IS A COMMON PULMONARY COMPLICATION FOLLOWING THORACIC AND UPPER ABDOMINAL PROCEDURES

General anesthesia and surgical manipulation lead to atelectasis by causing diaphragmatic dysfunction and diminished surfactant activity. The atelectasis is typically basilar and segmental in distribution. After induction of anesthesia, atelectasis increases from 1 to 11% of total lung volume. End-expiratory lung volume is also found to be decreased.

Postoperative atelectasis is extremely common. Lobar atelectasis is also common. The incidence and prevalence of this disorder are not well documented.

http://emedicine.medscape.com/article/296468-overview#a0104

Atelectasis occurs regularly after induction of general anesthesia, persists postoperatively, and may contribute to significant postoperative morbidity and additional health care costs. Laparoscopic surgery has been reported to be associated with an increased incidence of postoperative atelectasis.

Anesth Analg 2009; 109:1511-1516

Muliptle organ failure as a consequence of elective sympathectomy

In the post-sympathectomy patient, the abnormalsympathetic skin response may lead to peripheral vascular failureor the reduced cardiac chronotropic response may impair thebody’s capacity to compensate for shock. These may havecontributed to the rapid development of shock and severe multipleorgan dysfunction syndrome in this patient.
He had multiple organ dysfunction syndrome develop, with severerenal and hepatic failure, grade II hepatic encephalopathy,and disseminated intravascular coagulation. He responded remarkablywell to aggressive supportive measures including forced alkalinediuresis, and he was eventually discharged home after 1 month. The patient was previously a healthy, physically fit, nonsmoker.He worked as a body building trainer and led an active, sportylifestyle. The only significant medical history was that hehad received thoracic sympathectomy for axillary hyperhidrosis4 years ago at another hospital.

http://ats.ctsnetjournals.org/cgi/content/full/84/3/1025

our ignorance of the mechanisms of primary hyperhidrosis and of the effect of sympathetic ablation

hyperhidrosis is not related with social phobia or personality disorder

The total reward dependence and persistence scores were significantly higher in hyperhidrosis patients. The fear of uncertainty in the harm avoidance scale was found to be significantly greater in hyperhidrosis patients. Regarding character dimensions, the total score in each of the subscales self-directedness, cooperativeness and self-transcendence was found to be higher in hyperhidrosis patients. Conclusion: The higher scores of all subscales of character dimensions in hyperhidrosis patients suggest that hyperhidrosis is not related with social phobia or personality disorder.

http://www.online.karger.com/ProdukteDB/produkte.asp?Aktion=ShowFulltext&ArtikelNr=99589&Ausgabe=232867&ProduktNr=224164

Cell body reorganization in the spinal cord after surgery to treat sweaty palms and blushing

cross-inhibitory control of various afferent in the spinal cord

In conclusion, our results suggest that cross-inhibitory control by various afferents in the spinal cord may exist in the feet as well as in the contralateral hand. The release of cross-inhibitory control by T3 sympathicotomy results in vasoconstriction and a decrease of skin temperature on the contralateral hand and the feet.

The basic neuronal network for this reciprocal organization is probably located in the spinal level (15). Therefore, the reduction in the contralateral skin temperature may be explained by cross-inhibitory control of various afferent in the spinal cord.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2722005/

Contralateral temperature changes of the finger surface during video endoscopic sympathectomy for palmar hyperhidrosis
http://www.ncbi.nlm.nih.gov/pubmed/8832515

Receptor hypersensitivity is a common problem

Because of their size and location, injuries to the sympathetic ganglia or chain is rarely indicated or performed. Receptor hypersensitivity is a common problem after significant sympathetic injury, including clammy hands, erythema, and allodynia. When sympathetic nerves regenerate, they may establish aberrant connections to sensory receptors, muscles, or other sympathetics receptors; this may lead to an over-response or abnormal response.
http://wiki.cns.org/wiki/index.php/Injury,_Sympathetic_Nerve

Segmental myoclonus was associated with thoracic sympathectomy

Spinal myoclonus was associated with laminectomy, remote effect of cancer, spinal cord injury, post-operative pseudomeningocele, laparotomy, thoracic sympathectomy, poliomyelitis, herpes myelitis, lumbosacral radiculopathy, spinal extradural block, and myelopathy due to demyelination, electrical injury, acquired immunodeficiency syndrome, and cervical spondylosis.

http://www.ncbi.nlm.nih.gov/pubmed/3753263

Spinal myoclonus is typically associated with a localized area of damaged tissue (focal lesion). The injured area may include direct damage of the spinal cord or may cause abnormal changes in the function of the spinal cord.

http://www.wemove.org/myo/myo_pc.html

Spinal myoclonus following a peripheral nerve injury: a case report

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2526081/

Limited sympathectomy does not reduce severity of side-effects

On univariate and multivariate analysis, the extent of denervation was not associated with the occurrence or the severity of compensatory sweating.

Compensatory sweating and temporary relief/recurrence were equally considered to be the main causes of dissatisfaction. CONCLUSION: Compensatory sweating was the most common long-term complication of thoracodorsal sympathectomy for primary hyperhidrosis. Its incidence and severity were not associated with the extent of sympathectomy.

http://www.ncbi.nlm.nih.gov/pubmed/12514588

All patients except one suffered from compensatory sweating

Complications in patients with palmar hyperhidrosis treated with transthoracic endoscopicsympathectomy.

Neurosurgery. 1997 Jul ;41 (1):110-3; discussion 113-5 9218302

OBJECTIVE: To assess the complications in a group of patients with palmar hyperhidrosis treated with transthoracic endoscopic sympathectomy. The extraordinarily high incidence of postoperative compensatory hyperhidrosis in our series is stressed and explained. METHODS: The retrospective study included chart reviews and outpatient assessments. Seventy-two patients underwent T2 or T2-T3 endoscopic sympathectomy for primary palmar hyperhidrosis. Patients' hyperhidrosis severity, precipitating factors, postoperative complications, surgical results, and satisfaction were assessed. Severity of palmar hyperhidrosis and compensatory hyperhidrosis was classified by two grading scales. RESULTS: The success rate ofsympathectomy was 93%. All patients except one suffered from compensatory sweating,which was the main cause of patients' dissatisfaction postoperatively. Seventeen percent of the patients (12 of 72 patients) experienced new symptoms of gustatory sweating (facial sweating associated with eating). Twenty-one patients experienced other complications, including pneumothorax, Horner's syndrome,nasal obstruction, and intercostal neuralgia.

slowing of the heart rate usually occurs on the second to fourth day after sympathectomy

The rate fell to a level between 40 and 6o per minute, the maximal slowing usually occurring on the second to fourth day after operation. Consistent slowing of the rate was not observed after a unilateral thoracic sympathectomy of either side. While there was some recovery from the maximum bradycardia with the passage of time in most patients, relatively slow resting cardiac rates and failure of tachycardia to develop with postural hypotension or exercise persisted in all patients.

Skoog's12 work has shown that there are marked differences in the number and precise location of the accessory ganglion cells in the cervical region in different patients and on the two sides in the same patient.
Annals of Surgery, 1949 October, Volume 130 Number 4

'Emotional' sweating regulated by neocortex and limbic cortex

Careful observations showed that the forearm sweating responded diversely to various mental stimuli, unlike the palmar sweating whose response was always an increase. Mental arithmetic, mental testing and physical exercise caused an immediate increase in the palmar sweating but often elicited a transient decrease in the forearm sweating, whereas pain, noise, and emotional stimuli consistently provoked an increase of sweating on the forearm as well as on the palm. These observations suggest that the activities of higher centers, presumably involving neocortex and limbic cortex, exert various influences on the central mechanisms of palmar and generalized sweating.
Jpn J Physiol. 1975;25(4):525-36.
http://www.ncbi.nlm.nih.gov/pubmed/1206808

the muscles that are supplied by these nerves shorten and tighten

This now well-established but generally under-appreciated principle of physiology is aptly known as 'Cannon's Law of Denervation Supersensitivity'. It describes the wide ranging effects of the complete loss of nerve inputs to a variety of bodily structures under experimental conditions. One of the many responses to nerves that are sick or dysfunctional (now termed Disuse Supersensitivity) is that the muscles that are supplied by these nerves shorten and tighten (due to the supersensitivity of both the muscle's specialized stretch receptors and motor nerve-muscle junctions), resulting not only in muscle spasm and stiffness which limit flexibility, but a whole sequence of pain compounding reactions. The two earliest are that localized taut bands of muscle fibers begin to compress the small specialized pain sensing (and now extra-sensitive) nerve fibers within the muscle (known as myofascial tender or trigger points) causing type 1 pain, and the compressed muscles do not allow proper blood flow in, or waste products to be removed. This leads to a build up of lactic acid, which further enhances the perception of pain through type 2 pain mechanisms. Continued and prolonged muscle shortening or contracture gradually leads to increased mechanical tension on the muscle's tendonous attachments to bone, causing all of the various tendonitis (types 1 & 2 pain) syndromes throughout the body. The end result is a truly vicious snowballing cycle of pain, with the muscle shortening further increasing pressure on the nerves.

www.northwestims.com/faq-4.html

Cannon's law of denervation tells us that if a post-ganglionic neurone has it's pre-ganglionic input removed, then it will become super-sensitive to the normal neurotransmitters that mediate that pre-ganglionic input. There is a variety of reasons for this, including up-regulation of receptors for the neurotransmitter(s), post-receptor effects, and impaired removal of neurotransmitters from the synapse

www.anaesthetist.com/anaes/patient/ans/

Most authors do not describe clinically significant capsular adhesions as a predominant finding in the chronic phase of this condition. Instead, pathologic data confirm an active process of hyperplastic fibroplasia and excessive type III collagen secretion that lead to soft-tissue contractures of the aforementioned structures (ie, the coracohumeral ligament, soft tissues of rotator interval, the subscapularis muscle, the subacromial bursae). However, these findings were observed in surgical patients who had severe and late-phase disease and cannot be applied to early phases of the disease.

From the chromosomal, cytochemical, and histologic points of view, the soft-tissue contractures are identical to those seen in a Dupuytren contracture of the hand. These contractures result in the classic progressive loss of ROM of the glenohumeral joint, which affects external rotation and abduction, then flexion, adduction, and extension (in descending order of severity). Despite these histopathologic similarities, the favorable and regressive outcome of adhesive capsulitis differs from the unfavorable and progressive outcome of Dupuytren disease.

http://emedicine.medscape.com/article/326828-overview#a0104

These gustatory phenomena were quite different from physiologic gustatory sweating

In a series of 100 bilateral upper dorsal sympathectomiesperformed for palmar hyperhidrosis, gustatory sweating and othergustatory phenomena were reported by 68 of 93 patients (73%),followed up for an average of 11/2 years. These gustatory phenomenawere quite different from physiologic gustatory sweating: awide range of gustatory stimuli caused a variety of phenomenain varied locations. There was a negative correlation betweenthe incidence of these phenomena and the occurrence of Horner'ssyndrome after sympathectomy. Analysis of our observations,and of clinical and experimental work of others, leads to theconclusion that gustatory phenomena after upper dorsal sympathectomyare the result of preganglionic sympathetic regeneration orcollateral sprouting with aberrant synapses in the superiorcervical ganglion.

http://archneur.ama-assn.org/cgi/content/abstract/34/10/619

cervical sympathectomy is a psychosurgery

The courts have become the sole policing body for the medical profession

Major lawsuits, with the major judgments that go with them, may not completely keep negligent physicians from practicing, but they are the one way that currently exists to deter these individuals from practicing their inept brand of medicine. "

Over the years, we have given a lot of thought to why the medical profession adheres to this code of silence. What is it about this profession that causes it to protect its own at the expense of the public?"

Harvey F. Wachsman: Lethal Medicine

Publisher: Henry Holt & Co

Neuroma following nerve injury/surgery

When a nerve is cut, the piece of nerve that is beyond the cut point eventually dies, however, its Schwann cells, the cells that encircle the nerve fibers remain for a much longer time. These Schwann cells secrete a chemical messenger known as nerve growth factor that tells the cut end of nerve where to grow back. So the cut end of nerve will send out multiple sprouts in the direction of the nerve growth factor, however, these sprouts do not go out in an orderly manner, instead they grow out in all directions and eventually cluster and form a knot of nerve fibers. This eventually leads to the formation of a TRUE neuroma or a END BULB or STUMP neuroma.

www.tarsaltunnelcenter.com/assets/recurrent.shtml

Autonomic dysequilibrium (local sympathectomy) leading to obesity

A similar reduction of fat mobilization from fat depots occurs after VMH lesions, as after local sympathectomy, suggesting that the sympathetic pathway to the adipose tissue runs through the VMH.
Bray and York hypothesize that the change in energy balance in animals after VMH lesions is a result of autonomic dysequilibrium. The sympathetic outflow is reduced and the parasympathetic outflow increased. This shift in balance results in hyperinsulinemia and altered metabolic pathways leading to obesity. During the digestion and metabolism of a meal, the autonomic nervous system provides important (but not sole) feedback control on satiety.

The Nervous System and Adipose Tissue, By Katharine Dalziel, MD, MBBS, MRCP
Clinics in Dermatology
October-December 1989, Volume 7, Number 4, pages 62-77

the primary event of gustatory sweating is a degeneration of the cervical sympathetic neurons

The development of gustatory sweating after cervical sympathectomy can only be explained if one is to admit that the primary event of gustatory sweating is a degeneration of the cervical sympathetic neurons. The initial event is the loss of postganglionic sympathetic neurons and the resulting denervation of the corresponding facial sweat glands. Regeneration of parasympathetic fibers, within the degenerating sympathetic neurilemmal sheets, is a secondary event although it accounts for the observed symptoms.

Salivary gland disorders

Eugene N. Myers, Robert L. Ferris

Springer, 2007 - Medical - 517 pages

sympathectomy - controversy