Orhan Barlas

Do unilateral ablative lesions of the subthalamic nucleu in parkinsonian patients lead to hemiballism

We report the safety results in nine patients with advanced idiopathic Parkinsons disease (PD) who underwent ablative surgery of unilateral subthalamic nucleus (STN). In eight patients, surgical objectives were attained without induction of abnormal involuntary movements or other adverse effects. One patient developed transient hemiballistic movements which improved within 2 weeks after surgery. Assessment at 2 weeks to 20 months postoperatively revealed no long‐term adverse effects. We conclude that hemiballism following unilateral ablation of STN in patients with PD is a rare phenomenon, and unilateral ablative lesions of STN can be performed safely.

Stereotactic surgery in the management of brain abscess

BACKGROUND Bacterial brain abscesses can be diagnosed and treated with stereotactic aspiration. METHODS From 1991 to 1997 we have used computed tomography-guided stereotactic aspiration to diagnose and treat 21 patients with a total of 58 bacterial brain abscesses. The ages of the patients ranged from 4 to 72 years (median 25 years); 11 of these 21 patients had multiple abscesses. The number of abscesses per patient with multiple abscesses ranged from 2 to 9, all located deep in subcortical white matter. RESULTS All patients underwent stereotactic surgical drainage and an 8-week intravenous antibiotic medical treatment. Of the 58 abscesses, 23 were aspirated. Of these 23 abscesses, 19 were radiologically stage III or IV and four were stage I or II. Pathological examination confirmed radiological staging in 19 patients (83%). Except for the three patients who have mild residual hemiparesis and one patient recovering from ataxia, all patients had complete neurological recovery. CONCLUSIONS Computed tomography-guided stereotaxy achieved all the objectives of management; namely, ascertaining the diagnosis, draining the content of the mass, and obtaining pus for accurate bacteriological diagnosis without morbidity. Stereotactic aspiration combined with an 8-week intravenous antibiotic regimen has yielded an effective therapeutic result in all of our abscesses, small or large, solitary or multiple, superficial or deep-seated. A high radiological-pathological correlation was also deduced from this study.

Long-Term Follow-Up and Results of Thirty Pediatric Intracranial Hydatid Cysts: Half a Century of Experience in the Department of Neurosurgery of the School of Medicine at the University of Istanbul (1952–2001)

A series of 30 documented cases of intracranial hydatid cyst out of 33 pediatric and 45 total patients admitted to the Department of Neurosurgery of the School of Medicine at Istanbul University within the years 1952–1996 is presented. The pediatric population consisted of 73% of the series. Twenty patients (66%) are alive and well after a follow-up period of 8–45 years (mean 21.5 years). Six patients (20%) died and 4 (13%) were lost to follow-up. There were 3 early postoperative deaths (10%), 2 being in the pre-CT era. In 4 cases (13%), brain involvement was secondary, and 2 cases (7%) had multiple intracranial hydatid cysts. Age ranged from 4 to 16 years, with a mean of 10.4. There were 5 intraventricular (17%) and 2 (7%) intracranial extradural settlements. No children with posterior fossa hydatid cyst, primary skull hydatidosis or concomitant spinal involvement were detected. One patient (3%) presented with ‘rhinorrhea’ which in fact was a hydatid fluid leak. Preoperative pseudocerebellar syndrome, convulsion and extrapyramidal signs were seen in 6 patients each (20%). Five patients (17%) had permanent visual deficits, 3 being in pre-CT era. Out of 29 patients operated on, hydatid birth with intact cyst removal was achieved in 18 cases (62%), with no other manipulation needed. This rate has increased to 70% in the CT era. Intraoperative accidental rupture occurred in 8 cases (28%), of which 7 were localized frontally or had a frontal involvement (88% of the ruptured cases). Of the patients with intraoperative rupture, 5 are dead (63%) and they were all primary. In contrast, all 3 cases alive with intraoperative rupture are secondary. Three cases were punctured on purpose (10%). Four of the operated patients (14%) required long-term antiepileptic therapy, 3 having no preoperative seizures. Only 1 patient required a shunt (3%). Four cases had recurrence, all with intraoperative cyst rupture (14%). The long-term evaluation of the results yielded an overall mortality rate of 21%. Routine use of CT after the 80s decreased the rate to 14%. With the analysis of 50 years of data, it is strongly concluded that brain involvement in pediatric hydatid disease is a primary process if delayed diagnosis and insufficient treatment of extraneural hydatidosis are prevented.

Bromocriptine-induced cerebrospinal fluid fistula in patients with macroprolactinomas : report of three cases and a review of the literature

Bromocriptine therapy for macroprolactinoma induced cerebrospinal fluid (CSF) rhinorrhea in three patients. The tumor had extended well beyond the sella turcica and caused bony erosion in all the cases. All three patients responded to bromocriptine therapy rapidly. CSF fistula occurred concomitantly with the reduction of tumor size and caused meningitis in two of the patients. Withdrawal of bromocriptine resulted in cessation of the leakage. One of the patients underwent transsphenoidal repair. Two patients refused surgery. This potentially lethal complication encountered in these three cases demonstrates the need for close supervision of macroprolactinoma patients with skull base erosion placed under bromocriptine therapy.

Stereotactically guided microsurgical removal of colloid cysts.

Summary.Background. The surgical technique and clinical results for a series of 16 consecutive patients who underwent resection of third ventricular colloid cysts through a stereotactically guided cylindrical retractor are presented.Methods. Between March 1993 and December 2002, 16 patients, 11 males and 5 females with a mean age of 36, were admitted with colloid cysts of the third ventricle. Four patients had undergone previous surgery, of which two were simple aspirations, one endoscopic aspiration, and one transcallosal partial removal. Four patients required emergency ventriculostomies on admission. In all patients the foramen of Monro was targeted using a Leksell stereotactic frame. A coronal craniotomy three to four cm in diameter was performed and a cylindrical retractor 14 mm in diameter was advanced to the target. Microsurgical removal of the cyst was then performed through the retractor.Findings. Total removal of the cyst was achieved in all cases. Median follow-up time is 42 months. Complete resolution of symptoms occured in all patients. Control magnetic resonance imaging revealed no residual cysts. All patients have returned to their previous occupations without sequelae or epilepsy.Conclusion. The outcome obtained in this series has shown that transfrontal transforaminal total removal of colloid cysts through a stereotactically guided cylindrical retractor is a safe procedure.

Three Unusual Cases of Intracranial Hydatid Cyst in the Pediatric Age Group

Three unusual cases of hydatid disease with central nervous system involvement are reported in the pediatric age group: a 9-year-old boy with a total number of 12 intracranial secondary hydatid cysts; a 13-year-old girl admitted in areflexia who survived after cyst puncture and successive mass removal, and a 14-year-old boy with a huge intracranial hydatid cyst weighing 770 g which was extracted without rupture. The article discusses the surgical problems, and the related literature is reviewed.

Comparison of unilateral pallidotomy and subthalamotomy findings in advanced idiopathic Parkinson's disease.

A prospective, randomized, double-blind pilot study to compare the results of stereotactic unilateral pallidotomy and subthalamotomy in advanced idiopathic Parkinsons disease (PD) refractory to medical treatment was designed. Ten consecutive patients (mean age, 58.4 ± 6.8 years; 7 men, 3 women) with similar characteristics at the duration of disease (mean disease time, 8.4 ± 3.5 years), disabling motor fluctuations (Hoehn & Yahr stage 3–5 in off-drug phases) and levodopa-induced dyskinesias were selected. All patients had bilateral symptoms and their levodopa equivalent dosing were analysed. Six patients were operated on in the globus pallidus interna (GPi) and four in the subthalamic nucleus (STN). Clinical evaluation included the use of the Unified Parkinsons Disease Rating Scale (UPDRS), Hoehn&Yahr score and Schwab England activities of daily living (ADL) score in ‘on’- and ‘off’-drug conditions before surgery and 6 months after surgery. There was statistically significant improvement in all contralateral major parkinsonian motor signs in all patients followed for 6 months. Levodopa equivalent daily intake was significantly reduced in the STN group. Changes in UPDRS, Hoehn & Yahr and Schwab England ADL scores were similar in both groups. Cognitive functions were unchanged in both groups. Complications were observed in two patients: one had a left homonymous hemianopsia after pallidotomy and another one developed left hemiballistic movements 3 days after subthalamotomy which partly improved within 1 month with Valproate 1000 mg/day. The findings of this study suggest that lesions of the unilateral STN and GPi are equally effective treatment for patients with advanced PD refractory to medical treatment.

A Serial CT Scan and MRI Verification of Diffuse Cerebrospinal Gliomatosis: A Case Report with Stereotactic Diagnosis and Radiological Confirmation

Gliomatosis cerebri is an infrequent tumor of neuroepithelial origin presenting with deterioration of cognitive functions, behavioral and mental changes, motor weakness, headache, and seizures. Laboratory data are unconclusive. MRI appears to be the imaging modality of choice and mainly reveals a bilateral and diffuse infiltration of midline adjacent brain structures whose anatomical configuration remain intact. MRI- or CT-guided stereotactic biopsy is advised as the diagnostic procedure in suspected cases. A 9-year-old girl with diffuse cerebrospinal gliomatosis, investigated with sequential cranial CT scans, and MRI-verified spinal cord involvement is reported, and the corresponding literature is reviewed.

Tethered cord in the adult mimicking the lumbar disc syndrome: Report of two cases

Two adult patients with tethered cords whose symptoms mimicked those of lumbosacral intervertebral disc herniation are reported. Neither one of the patients had cutaneous stigmata, and one had normal plain x-ray examination of the spine. Magnetic resonance imaging in both patients demonstrated tethering of the cord. Untethering of the cord resulted in disappearance of the symptoms in both patients. These unusual cases suggest that tethering of the cord must be included in the differential diagnosis of the herniated lumbar intervertebral disc syndrome.

Interstitial Irradiation for Craniopharyngioma

Summary¶ The results of interstitial irradiation treatment for craniopharyngioma in two patients with six year follow-ups are presented. Stereotactic interstitial irradiation with Iodine-125 sources as sole therapy was employed in two adult patients who refused surgical resection. The diagnoses were confirmed by stereotactic biopsy. The first tumour which underwent interstitial irradiation was solid and 4 cm in diameter, and the second, 2.7 cm in diameter, had both cystic and solid components. The implanted Iodine-125 seeds delivered 67 Gy and 60 Gy to tumour periphery at the rate of 12 and 14 cGy/h, respectively, were removed at the end of designated radiation periods. Tumour shrinkage and central hypodensity, first observed 3 months after irradiation, continued until one tumour shrank to less than 1 cm at 12 months, and the other disappeared completely at 24 months. In both cases functional integrity was restored, and neither radiation induced toxicity nor recurrence has occurred six years after treatment. The results in these two cases suggest that solid craniopharyngiomas are sensitive to interstitial irradiation.