Incidentalomas of the adrenal gland: 36 operated patients and review of literature.

Incidental discovery of an adrenal mass during radiologic examinations is common. Several recommendations have been made for the management of so-called incidentalomas. It has become clear that not all incidentalomas should be operated, but the criteria for nonoperative treatment have been under continuous debate. In this study 36 operated incidentalomas are presented, and the indications for operative treatment are discussed with a review of the recent literature on the subject. Four pheochromocytomas and three hormonally active cortical adenomas, two producing cortisol and one androgens, were found. In this series there were no malignancies. The operation could have been avoided in most cases, and patients could have been followed up with repeated radiologic examinations. It is suggested that masses smaller than 6 cm in diameter be followed radiologically after 3, 9, and 18 months. Masses between 3 and 6 cm could be further examined using magnetic resonance imaging and fine needle aspiration and then operated if features suggestive of malignancy are found. Masses larger than 6 cm in diameter should be treated operatively.

Innervation of the rat Harderian gland by adrenergic and cholinergic nerve fibres.

The innervation of the rat Harderian gland was studied using histochemical methods for catecholamines and acetylcholinesterase (AChE). Selective denervations were performed to investigate the neural connections of this gland with various ganglia. Light microscopically the AChE-positive nerves seemed to run as thick bundles in the intertubular connective tissue. These bundles sent finer branches around the acini. The blood vessels, localized in the connective tissue septa, were surrounded by a dense plexus of AChE-containing fibres. By electron microscopy, the AChE-positive fibres were seen to terminate near the myoepithelial cells surrounding secretory cells. These fibres were also observed in contact with the blood vessels and occasionally close to the secretory cells. Fluorescent adrenergic nerves surrounded the blood vessels. Some fibres were also observed in the interlobular tissue. All the AChE-containing nerves degenerated after cutting the zygomatic nerve. On the other hand, removal of the ciliary ganglion or the superior cervical ganglion, or stereotactic coagulation of the ophthalmic nerve did not affect these nerves. The fluorescent adrenergic fibres disappeared following both removal of the superior cervical ganglion and coagulation of the ophthalmic nerve. These fibres were intact after removal of the ciliary ganglion.

Effects of denervations on the acetylcholinesterase-containing and fluorescent nerves of the rat iris.

The thiocholine method for the demonstration of AChE-containing fibres and the formaldehyde-induced fluorescence technique for the visualization of adrenergic fibres were employed to study the innervation of the albino rat iris. The following denervations were performed in order to verify the origins of different nerve types: (1) extirpation of the ciliary ganglion, (2) extirpation of the superior cervical ganglion, (3) stereotactic coagulation of the ophthalmic division of the trigeminal nerve, and (4) all possible combinations of the above-mentioned procedures. The denervations disclosed three main types of AChE-containing nerves in the iris: (1) nerve fibres degenerating after ciliary ganglionectomy, (2) thick nerve bundles in the dilator region disappearing after trigeminal neurotomy, and (3) fibres remaining intact after any type of denervation. Cervical sympathectomy had no effect on AChE-positive fibres. Under electron microscope AChE activity could be seen in the axolemma both in unmyelinated and in myelinated fibres. All fluorescent fibres vanished after ipsilateral cervical sympathectomy. Most of these fibres also disappeared after trigeminal neurotomy and the remaining fibres degenerated after subsequent ciliary ganglionectomy. On the basis of the present findings, the following conclusions can be drawn: (1) Most AChE-containing fibres of the rat iris originate in the ciliary ganglion. (2) The majority of the myelinated sensory fibres of the rat iris also contain AChE. (3) There is no AChE in the adrenergic fibres of the rat iris. (4) All adrenergic fibres of the rat iris originate in the ipsilateral superior cervical ganglion, and (5) these fibres enter the iris along with both the long and short ciliary nerves.