Giustino Tomei

Pulsed radiofrequency effects on the lumbar ganglion of the rat dorsal root: a morphological light and transmission electron microscopy study at acute stage

Since the dorsal root ganglia represent the first structure of pain modulation, they are the target of the newest therapies of neuropathic pain. Between these, pulsed radiofrequency (PRF) has been described among the promising non-invasive methods. Although the results encourage the clinical use of this procedure, their mechanism of action is still unclear. Aim of our study was to analyze acute effects of PRF on the rat lumbar ganglion and on nervous fibres running inside it. Clinical works describe PRF treatment as a techinque without any visible neurological deficit. The few disposable histological works are contractictory: some describe no signs of cellular damage and some demonstrate visible intracellular modifications. A total of 20 male Wistar rats were deeply anesthesized. Ten were positioned in a stereotactic system, and exposed to PRF at 2xa0Hz for 30xa0s after exposition of paravertebral muscles and positioning of a stimulation needle on left L4 ganglion. The other ten were used as controls. After 1xa0h, the left dorsal root ganglions L3, L4, L5 of the 20 animals were explanted, fixed in 2.5% Karnowsky solution and prepared for light and transmission electron microscopy. At light microscopy no differences between treated and control animals were observed; at transmission electron microscopy, instead, it was possible to observe that T gangliar cells contained an abnormal abundant smooth reticulum with enlarged cisternae and numerous vacuoles; myelinated axons presented pathological features and their myelin coverage was not adherent. Instead, unmyelinated axons appeared normal in shape and dimension and the Schwann cells surrounding it had intact plasmamembrane. Our results, obtained at acute stage, reveal that the PRF procedure should destroy the myelin envelope of nervous fibres. Further future studies, at chronic stage, should give other information on the prognosis of the myelinic damage.

The Infection Risk of Intrathecal Drug Infusion Pumps after Multiple Refill Procedures

The objective of this study was to evaluate the long‐term infection risk from refilling intrathecal drug delivery devices. We studied 25 patients (14 females and 11 males) with intrathecal infusion pumps placed for spasticity (23 patients) and chronic pain (two patients). In this study group there were 890 refill procedures (mean 35.6 ± 20.5; range 8–72 times) performed on an outpatient basis by four different physicians. All refill procedures were performed in a sterile and standardized fashion as suggested by the manufacturer, using manufacturers approved kits for the refills. During the study period, five patients had recurrent infection of the urinary tract and three patients had recurrent infections of the respiratory tract. At the last pump refill of each patient, residual drug, extracted from the pump reservoir, was sent to a laboratory for aerobic and anaerobic cultures. All cultures, in all pumps, were negative for aerobic and anaerobic bacteria. We conclude that periodic refills of intrathecal implanted pumps do not seem to be a risk factor for infection if standard sterile refill procedures are performed. In this study, it was clear that comorbid infections from other parts of the body do not present as a risk for device contamination.

Management of spasticity in multiple sclerosis by intrathecal baclofen

Since its introduction, chronic intrathecal baclofen (ITB) infusion has been proved to improve spasticity, spasms and related pain. In the literature, the reported clinical improvement is evident in more than 85% of the patients suffering from spasticity and in more than 66% of the patients suffering from spasms. Usually, the evaluation of spasticity is carried out by the Asworth Scale although there is not yet general accordance on the validity of this scale. It is possible that some of the scales used to assess the implanted patients are not sensitive enough to detect changes in the quality of life or functional outcome. After the pumps implantation, the overall care seems to be rather simple for a devoted team. The side effects are usually temporary but they can worry the patients. The most dangerous side effects are baclofen overdose and withdrawal syndrome. These complications are totally avoidable by adopting an approach attentive to the details regarding the patient, the device, and the procedure.

Impact of cerebrovascular disease on the surgical treatment of idiopathic normal pressure hydrocephalus

OBJECTIVE:The influence of cerebrovascular disease (CVD) on the short- and long-term results of surgery was evaluated in a series of consecutive patients with idiopathic normal-pressure hydrocephalus (iNPH). METHODS:Patients with suspected iNPH admitted to our department between June 1996 and June 2003 were evaluated with four clinical and handicap scales. CVD and risk factors for vascular disease were rated. All patients underwent intracranial pressure monitoring via a spinal catheter. Sixty-six patients received a ventriculoperitoneal shunt with a programmable valve. Prospective assessments were programmed at 2 weeks and 3 months after surgery (short-term follow-up). Long-term follow-up evaluations were arranged in June 2004 with patients and/or relatives and health/home care assistants. RESULTS:At the short-term follow-up examination, a significant clinical improvement was globally present in 89% of the patients (P < 0.05). CVD, such as leucoaraiosis or previous strokes, were present in 71% of the patients. Patients both with and without CVD and/or risk factors for vascular disease presented a significant improvement (P < 0.05) after shunting; 85 and 100% of the patients with and without CVD, respectively. At the long-term follow-up examination (mean, 52 ± 24.8 mo), 24% of the patients were dead and 8% had experienced stroke. Globally, 60% of the patients were still improved (P < 0.05); 52 and 79% of the patients with and without CVD, respectively. CONCLUSION:A high success rate in treatment of iNPH is possible in patients with and without CVD. Despite poorer short- and long-term treatment outcome of iNPH patients with CVD, a long-lasting improvement in their quality of life favors surgery.

Mixed pituitary adenoma/craniopharyngioma: clinical, morphological, immunohistochemical and ultrastructural study of a case, review of the literature, and pathogenetic and nosological considerations

Mixed pituitary adenoma/craniopharyngiomas are very rare tumors. Their pathogenesis is still unclear and it is not known whether they are collision tumors derived from independent stem cells or whether they originate from a single stem cell undergoing divergent differentiation. The latter hypothesis is supported by the close commixture between the two tumor components with transition areas that has been previously described. However, “hybrid” cells with both pituitary adenoma and craniopharyngioma features have never been described. In this paper we report a case of mixed pituitary adenoma/craniopharyngioma observed in a 75-year-old woman presenting with diplopia and slight increase of serum prolactin, who underwent endoscopic endonasal trans-sphenoidal tumor resection. Histologically, the tumor was composed of a typical pituitary silent subtype 2 ACTH cell adenoma admixed with islands of adamantinomatous craniopharyngioma. Electron microscopy showed that, in addition to distinct silent subtype 2 ACTH and craniopharyngioma cells, there were “hybrid” cells, showing characteristics of both pituitary adenoma and craniopharyngioma, consisting of small dense secretory granules, bundles of cytoplasmic filaments, and desmosomes. This ultrastructural finding was also confirmed by the presence of cells showing nuclear p40 expression and chromogranin A immunoreactivity. The close commixture between the two components and the ultrastructural and immunohistochemical findings demonstrate a common histogenesis of the two components and support the classification of the neoplasm as a mixed tumor. The patient completely recovered and, 10xa0months after surgery, head MR confirmed the complete resection of the lesion.

A case of post–traumatic cervicogenic headache treated by cervical cord stimulation

The case of a 26–year–old woman suffering from cervical trauma with disc herniation presenting with arm and neck pain is presented. She underwent cervical discectomy with fusion because the pain did not improve with medical therapies; as the neck pain resumed after surgery, a cervical cord neurostimulator was implanted, with improvement for cervicogenic headache. This report underlines the presence of two pathologies and the relationship between C2 and trigeminal pathways.

Rare case of Cushing's disease due to double ACTH-producing adenomas, one located in the pituitary gland and one into the stalk

We describe a patient affected by Cushing’s disease due to the presence of double pituitary adenomas, one located within the anterior pituitary and the other in the infundibulum associated with a remnant of Rakthe’s pouch. Cure was achieved only after the infundibulum lesion was surgically removed. CASE REPORT: A 38-year-old female presented with unexplained weight gain, hirsutism, amenorrhea, asthenia, recurrent cutaneous micotic infections and alopecia. Hormonal studies indicated Cushing’s disease and MRI showed an enlarged pituitary gland with a marked and homogeneous enhancement after injection of gadolinium and an enlarged infundibulum with a maximum diameter of 8 mm. As a venous sampling of the inferior petrosal sinus after 10 µg iv desmopressin stimulation revealed a central to peripheral ACTH ratio consistent with a pituitary ACTH-secreting tumor, transphenoidal explorative surgery was performed and a 4-mm pituitary adenoma immunopositive for ACTH was disclosed and removed. Since postoperative hormonal evaluation showed persistent hypercortisolism, confirmed by dynamic tests, the patient again underwent surgery by transcranial access and the infundibulum mass was removed. Histology and immunochemistry were consistent with an ACTH-secreting adenoma. A few months after the second operation, cushingoid features were significantly reverted and symptoms improved. CONCLUSION Although Cushing’s patients bearing multiple adenomas have already been documented, the presence of two adenomas both immunohistochemically positive for ACTH is a very rare cause of Cushing’s disease and this is the first report of a case of double ACTH-producing adenomas, one located in the pituitary gland and one attached to the stalk.

Mixed cranial nerve neuroma revealing itself as baroreflex failure

We report here the first case of baroreflex failure due to a mixed cranial nerve neuroma in which the clinical manifestations (recurrent severe hypertensive crisis, hypotension) due to baroreflex arc impairment preceded the clinical diagnosis of brain tumour and neurosurgery by a few months. Given the clinical suspicion of baroreflex failure, even in the absence of iatrogenic clues, we propose that the patients study should include neuroradiologic evaluation of the ponto-cerebellar angulus.

An unusual case presenting with hypertensive crisis

signs. The chest was clear to auscultation, and heart sounds were normal without murmurs. The abdomen was plain and not tender, without masses or organomegalies. Results of urinalysis, complete blood count, serum electrolyte levels, hepatic-function and renal-function tests showed no abnormalities. A 24-h ambulatory blood pressure monitoring was then performed (Spacelabs 90207-30, with recording of blood pressure every 15 min), revealing a normotensive state throughout the registration (24 h mean blood pressure: 125±12/68±8 mmHg; preserved nocturnal blood pressure fall). An echocardiogram revealed normal parietal thickness and function and a radiograph of the chest showed no abnormalities.