One-Year Follow-Up of Subthalamic Nucleus Deep Brain Stimulation in SNCA Mutation Parkinsonism: A Case Report.

Background: Deep brain stimulation (DBS) has shown some efficacy in monogenic Parkinson's disease; however, data about its long-term benefit in SNCA mutations remain scarce. Case report: Subthalamic nucleus DBS was implanted in a 60-year-old female patient with Parkinson's disease due to SNCA duplication. One year later, the patient walked unassisted and was independent for most activities of daily living, without requiring any anti-Parkinson's medication. Discussion: To our knowledge, four cases of bilateral subthalamic DBS have been reported previously. This case report adds an additional body of evidence of improved one-year outcome after DBS surgery in a patient with SNCA mutation. Highlights: This is a case report of a patient with genetic parkinsonism due to SNCA duplication undergoing bilateral subthalamic nucleus (STN) deep brain stimulation (DBS) surgery. The outcome was favorable one year after implantation, with the patient coming off all anti-Parkinson's medications. This further clarifies DBS outcome in monogenic Parkinson's disease.

Management of benign nerve sheath tumors of the brachial plexus: relevant diagnostic and surgical features. About a series of 17 patients (19 tumors) and review of the literature.

Brachial plexus (BP) tumors are rare, potentially difficult-to-manage lesions. The method is retrospective chart analysis. Among the 17 patients, four had neurofibromatosis and one schwannomatosis (NF +). The latter has bilateral BP tumors that remain stable on MRI at a 6.5 year follow-up. Another NF + patient has bilateral non-operable BP plexiform neurofibromas. The complaints of the 15 operated patients were radiated pain, a mass, local pain, paresthesia, a neurological deficit (n = 15, 12, 7, 10, 7). On MRI, the tumors appeared as nodular or ovoid large masses. Four operated tumors were proximal, reaching the foramen. The FDG-PET scan (n = 4) always showed tumor hypermetabolism. A preoperative percutaneous biopsy was done in three patients before neurosurgical consultation; one of them developed neurogenic pain and a sensory deficit following two percutaneous biopsies for a misinterpreted cervical lymphadenopathy. Surgery was performed using a supra-, infra-, supra- + infra-clavicular or posterior subscapular approach (n = 8, 3, 3, 1). Intraoperative electrophysiology was used in all patients. Complete or gross total resection was achieved in 14 patients. Two patients had fascicle reconstruction with grafts. Pathology revealed 13 schwannomas and two neurofibromas. Neurogenic pain transiently developed or worsened after surgery in five patients. At last follow-up, a mild deficit remained in four patients (preexisting in three). No recurrence had occurred. We conclude that a thorough examination of any patient with a cervical or axillary mass is crucial to avoid misinterpretation as a lymphadenopathy. MRI is the best imaging modality. Most BP benign tumors can be completely and safely resected through the use of microsurgical techniques and intraoperative electrophysiology.

Iatrogenic nerve injuries: a potentially serious medical and medicolegal problem. About a series of 42 patients and review of the literature.

OBJECTIVE: To analyze the management of iatrogenic nerve injuries (iNI) in 42 patients. METHODS: Retrospective analysis of the charts. RESULTS: The iNI occurred mostly during a surgical procedure (n = 39), either on a nerve or plexus (n = 13), on bone, joint, vessel or soft tissue (n = 24) or because of malpositioning (n = 2). The most commonly injured nerves were the brachial plexus, radial, sciatic, femoral, or peroneal nerves. 42.9% of the patients were referred later than 6 months. A neurological deficit was present in 37 patients and neuropathic pain in 17. Two patients were lost to follow-up. Conservative treatment was applied in 23 patients because of good spontaneous recovery or compensation or because of expected bad prognosis whatever the treatment. Surgical treatment was performed in 17 patients because of known nerve section (n = 2), persistent neurological deficit (n = 12) or invalidating neuropathic pain (n = 3); nerve reconstruction with grafts (n = 8) and neurolysis (n = 8) were the most common procedures. Outcome was satisfactory in 50%. Potential reasons of poor outcome were a very proximal injury, placement of very long grafts, delayed referral and predominance of neuropathic pain. According to the literature delayed referral of iNI for treatment is frequent. We provide an illustrative case of a young girl operated on at 6.5 months for femoral nerve reconstruction with grafts while nerve section was obvious from the operative note and pathological tissue analysis. Litigation claims (n = 10) resulted in malpractice (n = 2) or therapeutic alea (n = 5) (3 unavailable conclusions). i CONCLUSIONS: NI can result in considerable disability, pain and litigation. Optimal management is required.

Post-traumatic thoracic outlet syndrome.

BACKGROUND: To evaluate the clinical presentation, diagnostic and therapeutic management and outcome of 27 cases of post-traumatic thoracic outlet syndrome (PT TOS). METHODS: Retrospective chart analysis. RESULTS: Nineteen women and eight men were included in this study. Involvement in a traffic accident was the most common scenario. Fracture of either the first rib or the clavicle was reported in eight patients at the time of injury; in others, the diagnosis was cervical or shoulder soft tissue trauma. Upon presentation at our clinic at a mean 41 months after injury, four patients had bilateral symptoms and 17 reported decreased function of either the arm or hand. Two patients presented with severe lower trunk deficits including one who had received surgical intervention at both the cervical spine and elbow before diagnosis of TOS was made. Sixteen and 15 patients were suffering from some degree of anxiety and/or depression. Upon diagnosis of neurogenic TOS, the two patients with atrophy of the hand musculature were treated surgically. Conservative treatment was applied to all other patients. Six months after presentation to our clinic, nine patients demonstrated a significant improvement. The remainder that reported incapacitating symptoms were offered surgical treatment. Three patients declined the latter. Fifteen patients received surgical treatment via an anterior supraclavicular approach with resection of the anterior scalene muscles. Eleven patients had resection of the middle scalene muscle while five had resection of an osseous structure (partial claviculectomy, C7 transverse process or a cervical rib). The two patients with atrophy of the hand only slightly improved their motor deficit but had a notable relief of symptoms of pain. Postoperative improvement occurred in 80% of surgically treated patients. CONCLUSIONS: The majority of patients suffering from a post-traumatic TOS present a neurogenic, usually subjective syndrome. Prompt therapeutic management is necessary, addressing both physical and psychological complaints. Most patients are cured or well improved by conservative and/or surgical treatment.

Brain energization in response to deep brain stimulation of subthalamic nuclei in Parkinson's disease.

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an effective treatment in a subgroup of medically refractory patients with Parkinson's disease (PD). Here, we compared resting-state (18)F-fluorodeoxyglucose (FDG) positron emission tomography images in the stimulator off (DBS_OFF) and on (DBS_ON) conditions in eight PD patients in an unmedicated state, on average 2 years after bilateral electrode implantation. Global standardized uptake value (SUV) significantly increased by ∼11% in response to STN-DBS. To avoid any bias in the voxel-based analysis comparing DBS_ON and DBS_OFF conditions, individual scan intensity was scaled to a region where FDG-SUV did not differ significantly between conditions. The resulting FDG-SUV ratio (FDG-SUVR) was found to increase in many regions in response to STN-DBS including the target area of surgery, caudate nuclei, primary sensorimotor, and associative cortices. Contrary to previous studies, we could not find any regional decrease in FDG-SUVR. These findings were indirectly supported by comparing the extent of areas with depressed FDG-SUVR in DBS_OFF and DBS_ON relatively to 10 normal controls. Altogether, these novel results support the prediction that the effect of STN-DBS on brain activity in PD is unidirectional and consists in an increase in many subcortical and cortical regions.

Surgical management of anterior cranial base fractures with cerebrospinal fluid fistulae: a single-institution experience.

OBJECTIVE: The management of cerebrospinal fluid (CSF) fistulae after anterior cranial base fracture remains a surgical challenge. We reviewed our results in the repair of CSF fistulae complicating multiple anterior cranial base fractures via a combined intracranial extradural and intradural approach and describe a treatment algorithm derived from this experience. METHODS: We retrospectively reviewed the files of 209 patients with an anterior cranial base fracture complicated by a CSF fistula who were admitted between 1980 and 2003 to Liège State University Hospital. Among those patients, 109 had a persistent CSF leak or radiological signs of an unhealed dural tear. All underwent the same surgical procedure, with combined extradural and intradural closure of the dural tear. RESULTS: Of the 109 patients, 98 patients (90%) were cured after the first operation. Persistent postoperative CSF rhinorrhea occurred in 11 patients (10%), necessitating an early complementary surgery via a transsphenoidal approach (7 patients) or a second-look intracranial approach (4 patients). No postoperative neurological deterioration attributable to increasing frontocerebral edema occurred. During the mean follow-up period of 36 months, recurrence of CSF fistula was observed in five patients and required an additional surgical repair procedure. CONCLUSION: The closure of CSF fistulae after an anterior cranial base fracture via a combined intracranial extradural and intradural approach, which allows the visualization and repair of the entire anterior base, is safe and effective. It is essentially indicated for patients with extensive bone defects in the cranial base, multiple fractures of the ethmoid bone and the posterior wall of the frontal sinus, cranial nerve involvement, associated lesions necessitating surgery such as intracranial hematomas, and post-traumatic intracranial infection. Rhinorrhea caused by a precisely located small tear may be treated with endoscopy.

Long-term follow-up reveals low toxicity of radiosurgery for vestibular schwannoma.

AIM: The long-term effects of radiosurgery of vestibular schwannomas were investigated in a group of consecutively treated patients. METHODS AND MATERIALS: Between 1995 and 2001, 26 patients (median age: 67, range: 30-82) with a vestibular schwannoma were treated by Linac-based stereotactic radiosurgery (SRS). The median follow-up was 49 months (16-85 months). Only progressive tumours were treated. The median size of tumours was 18 mm (range 9-30 mm). Before SRS, 11 patients had a useful hearing (Gardner-Robertson classes 1 and 2). Single doses of 10-14 Gy were prescribed at the 80% isodose at the tumour margin. The follow-up consisted of regular imaging with MRI the first 3-6 months after the intervention, followed by additional yearly MRIs, a hearing test and a neurological examination. RESULT: The 5-year-probability of tumour control (defined as stabilization or decrease in size) was 95%. Five-year-probability of preservation of hearing and facial nerve function was 96% and 100%, respectively. Hearing was preserved in 10 out of 11 patients who had a normal or useful hearing at the time of treatment. Mild and transient trigeminal toxicity occurred in 2 (8%) patients. It appeared to be significantly correlated to the dose used (p=0.044). However, only a tendency to significance could be demonstrated in the relationship between the two factors when using the Cox analysis (hazard ratio=1.7; 95% CI: 0.7-3.9; p=0.23). CONCLUSIONS: With the doses used, our study demonstrates that SRS provides an equivalent tumour control rate when compared to surgery, as well as on a long-term basis, an excellent preservation of the facial and the acoustic nerves. Although no permanent trigeminal toxicity was observed, our data confirm that doses below 14 Gy can avoid transient dysesthesias.

PET imaging for differentiating recurrent brain tumor from radiation necrosis.

The exact incidence of true radiation necrosis is largely unknown. It is probably much less frequent than indicated by MR or CT findings. Differentiating radiation necrosis from recurrent tumor is a diagnostic challenge, however, and has important implications for the patient's management. Even though the first results were published 20 years ago, the total number of case studies using FDG-PET in this indication remains limited. Several reports are also hampered by methodologic limitations. The technique has been largely criticized, notably in articles that themselves were not completely free of methodological flaws. Overall however, FDG-PET seems to be a valuable clinical tool. As a general rule, suspicious lesions on MR imaging that show increased FDG uptake (ie, uptake equal to or great than that in normal cortex) are likely to represent tumor recurrence. Sensitivity is an issue, especially but not exclusively with low-grade gliomas. Although false-positive results may occur, specificity is usually high in routine clinical practice. Coregistration with MR imaging surely improves the diagnostic performances of FDG-PET because it helps delineate the suspicious area. Another important aspect is the prognostic value of FDG uptake, which is now well established. It seems clear that only the combination of FDG with a radiolabeled amino acid analogue (MET or a more recent fluorinated compound) can provide a comprehensive characterization of suspected brain tumor recurrence.

Primary central nervous system lymphoma report of 32 cases and review of the literature.

We retrospectively analyzed 32 cases of primary central nervous system lymphoma (PCNSL). Five cases were diagnosed in the period 1987-1994, for 27 cases in the period 1995-2002. There were 17 men and 15 women whose median age was 69 years. Three patients were immunodeficient. The commonest symptoms were focal deficit (16 patients) and cognitive/behaviour disturbances (14 patients). Radiologically, a total of 47 contrast-enhancing lesions were observed in 32 patients; 18 patients had deep-seated lesions. All but two patients underwent histological diagnosis following craniotomy (11 patients) and/or stereotaxic biopsy (22 patients); diagnosis was obtained on CSF cytology in one patient with a third ventricle tumour. In the last patient, the diagnosis was based on the finding of marked tumour shrinkage under corticotherapy, despite two negative histological examinations. Treatment included surgical resection (10 patients), chemotherapy (25 patients) and/or radiotherapy (12 patients). According to the therapeutic recommendations of the GELA (Groupe d'Etude des Lymphomes de l'Adulte), 19 patients received at least two courses of high-dose methotrexate; intrathecal chemotherapy was used in 20 patients with methotrexate and/or cytosine arabinoside. Radiation therapy consisted of whole brain irradiation followed by a boost on tumour site. Nine patients received a combined treatment of chemotherapy and radiotherapy. Twelve patients showed rapid progression to death. At the time of last contact, 28/32 patients (88%) had died, all from PCNSL disease or from complications due to its treatment. The median survival time was 13.9 months. We conclude that PCNSL is an increasingly frequent tumour. The diagnosis is obtained by stereotactic biopsy in the majority of cases. The prognosis appears dismal despite an intensive multidisciplinary therapeutic approach.