Intrasellar arachnoid cysts.

OBJECTIVE: To evaluate the clinical, endocrinological, and radiological presentation of nine cases of surgically verified intrasellar arachnoid cysts and to discuss the physiopathological mechanisms of formation of these cysts. METHODS: Among 1540 patients presenting with pituitary lesions, nine presented with an intrasellar arachnoid cyst. Their charts were retrospectively reviewed. RESULTS: Presenting symptoms included headache (n = 2), visual symptoms (n = 3), menstrual irregularities (n = 2), rapid weight gain (n = 1), vertigo (n = 1), and/or confusion (n = 1). Two cysts were discovered incidentally. T1-weighted magnetic resonance imaging scans showed an intrasellar cystic lesion in all cases, with a huge suprasellar extension in six cases. The cyst was of the same intensity as the cerebrospinal fluid (CSF) in only two patients. A transsphenoidal approach allowed the transdural aspiration of fluid and injection of a water-soluble contrast agent under mild pressure. In three patients, the contrast infiltrated along the pituitary stalk toward the subarachnoid spaces; in the other patients, it remained in the intrasellar compartment. Cyst membranes were removed as completely as possible with fenestration toward the subarachnoid spaces in communicating cysts. In spite of tight packing of the sella and sphenoid sinus, CSF fistulae requiring reoperation developed in two patients. CONCLUSION: The clinical picture of an intrasellar arachnoid cyst resembles that of a nonfunctional pituitary adenoma. Magnetic resonance imaging scans typically show a cystic intrasellar lesion with suprasellar extension, containing isointense or, more often, hyperintense fluid on T1-weighted sequences. In spite of the risk of CSF fistulae, the preferred surgical approach is transsphenoidal. A physiopathological mechanism is proposed according to anatomic variations of the sellar diaphragma allowing penetration of subarachnoid spaces into the sellar compartment and their enlargement by a ball-valve mechanism.

Classical pituitary tumour apoplexy: clinical features, management and outcomes in a series of 24 patients.

We retrospectively analysed the incidence, clinical presentation, endocrinological and radiological findings, medical and surgical management of pituitary apoplexy in our department (single-centre study), having a large experience in pituitary surgery. Among 1540 pituitary lesions, 24 patients presented with pituitary apoplexy. Their charts were retrospectively reviewed. The symptoms included headache (92%), nausea and vomiting (54%), visual deficit (50%), oculomotor paresis (54%) and/or an altered mental state (42%). Skull X-rays (n = 14) demonstrated an enlarged sella turcica in all cases; CT-scan and/or MRI always revealed a sellar and suprasellar expanding lesion. Panhypopituitarism was present on admission in 70% of the patients. Urgent therapeutic management included high-dose cortisone treatment in all but one patients and CSF drainage in three. Three patients were treated conservatively. Nine patients were operated on rapidly, within hours or a few days because of severe visual deficit and/or altered level of consciousness. Nineteen patients were operated by the trans-sphenoidal approach; one of them required a second operation by craniotomy. There were two deaths related to the illness and one to an ill-defined reason at 4 months. Among the other patients 95% made a good recovery. All but two patients required a substitutive treatment with adrenal (83%), thyroid (68%), gonadal (42%) and/or growth (16%) hormones. The preoperative visual deficits recovered in all but one patients (92%) whereas the oculomotor pareses improved in all but two patients (85%). In conclusion, pituitary tumour apoplexy is a rare event, complicating in our series 1.6% of 1540 pituitary adenomas. Even in severe cases, complete recovery is possible if the diagnosis is rapidly obtained and adequate management is initiated in time. Surgical results after trans-sphenoidal approach are in the majority of cases very satisfactory.

Brachial plexus injury: a survey of 100 consecutive cases from a single service.

OBJECTIVE: We analyzed the epidemiology, preoperative management, operative findings, operative treatment, and postoperative results in a group of 99 patients who sustained 100 injuries to the brachial plexus. METHODS: The charts of 100 consecutive surgical patients with brachial plexus injuries were reviewed. RESULTS: The patient group comprised 80 males and 19 females ranging from 5 to 70 years of age. One male patient had bilateral brachial plexus palsy. Causes of injury were largely sudden displacement of head, neck, and shoulder and included 27 motorcycle accidents. There were 23 open wounds, including 8 gunshot wounds, 6 other penetrating wounds, and 9 wounds caused by operative or iatrogenic trauma. Loss was exhibited at C5-C6 in 19 patients, at C5-C7 in 15 patients, and at C5-T1 in 39 patients, and 8 patients had another spinal root pattern of injury. Nineteen patients had injury at the cord or the cord to nerve level. Associated major trauma was present in 59 patients. Emergency surgery for vessel or nerve repair was necessary in 18 patients. Myelography (n = 57) or magnetic resonance imaging (n = 7) revealed at least one root abnormality in 52 patients. The median interval from trauma to operation was 7 months. Operative exposures used included anterior supraclavicular, infraclavicular, combined supra- and infraclavicular, or a posterior approach in 5, 14, 77, and 4 patients, respectively. The surgical procedures performed included neurolysis alone in 12 patients and nerve grafting, end-to-end anastomosis, and/or neurotization in 81, 5, and 47 patients, respectively. Postoperative follow-up of at least 36 months was conducted in 78% of the patients. Grade 3 recovery according to Louisiana State University Medical Center criteria means contraction of proximal muscles against some resistance and of distal muscles against at least gravity. Among the 18 patients with open wounds, 14 (78%) recovered to a Grade 3 or better level, as did 35 (58%) of 60 patients with stretch injuries. In all cases of C5-C6 stretch injuries repaired by nerve grafting (n = 10), the patients recovered useful arm function. CONCLUSION: Brachial plexus injury represents a severe, difficult-to-handle traumatic event. The incidence of such injuries and the indications for surgery have increased during recent years. Graft repair and neurotization procedures play an important role in the treatment of patients with such injuries.

Development of a reconstituted nerve in a three-dimensional collagen gel under tension populated with fibroblasts and Schwann cells.

Our aim is to devise an artificially reconstituted nerve segment made of a three-dimensional collagen gel populated with aligned fibroblasts and Schwann cells. Collagen lattices were prepared by mixing concentrated medium, a type I collagen solution and rat Schwann cells (SC), rat neural fibroblasts (nF) or human dermal fibroblasts (dF) and allowed to polymerize at 37 degrees C. In these free-floating lattices, nF and dF retracted the gel more than SC. All cells appeared to be elongated and oriented at random. Rat cells obtained by enzymatic digestion of nerves undergoing wallerian degeneration retracted the gel at a larger extent than cells from intact nerves. Rectangular lattices restrained at each extremity acquired a paraboloid shape upon retraction by neural or dermal F reflecting the mechanical tension developed by these cells on their support. Adult SC alone produced a faint paraboloid even at high cell density while SC associated with nF developed a paraboloid similar to that obtained with nF alone. The mechanical force developed by dermal F and SC in the restrained lattice was measured by strain gauges and found much higher for F than for SC. In restrained lattices, both types of F were elongated and aligned to the long axis of the gel while SC elongated but not necessarily in a parallel fashion. The central portion of a mixed nF-SC collagen restrained lattice produces a flattened cylindric segment made of longitudinally oriented col-lagen fibrils, F and SC, which could represent a promising material for preparation of nerve grafts. An original plastic mould was devised to allow the preparation of cylindrical segments of free or restrained collagen lattices in view of in vitro and in vivo regeneration studies.