Horner's syndrome secondary to T1-T2 intervertebral disc prolapse.

Background: T1-T2 intervertebral disc prolapse (IVDP) is a rare clinical condition. Horner's syndrome is an extremely rare clinical finding in these patients. Case Description: A 56-year-old man presented with the left C8 T1 radiculopathy, left hand grip weakness, and ipsilateral Horner's syndrome. Magnetic resonance imaging of the spine showed a contrast-enhancing lesion in the left T1 foramen compressing the left T1 nerve root. He underwent left T1 hemilaminectomy, upper half of left T2 hemilaminectomy and removal of the left foraminal lesion. A biopsy of the lesion was sent for histopathological diagnosis which revealed tissue consistent with disc material. Postoperatively, he had near-complete recovery with residual minimal Horner's syndrome. Conclusion: T1-T2 IVDP should be considered in the differential diagnosis when a patient presents with C8 T1 radiculopathy and Horner's syndrome.

Ceftriaxone-induced encephalopathy in a patient with multicentric glioma.

Background: Ceftriaxone is a commonly used antibiotic in a wide range of local and systemic infections. Encephalopathy is a rare complication of ceftriaxone, often seen in older adults and those with renal insufficiency. Case Description: A 73-year-old lady with prior history of hypertension and dyslipidemia presented with the complaints of slurred speech, gait imbalance, nocturnal vomiting, and progressively worsening headache. A magnetic resonance imaging of the brain revealed two intracerebral lesions involving the right frontal and temporal lobes, suggestive of multicentric glioma. She underwent craniotomy and excision of these lesions. The biopsy was reported as intra-axial tumors with features suggestive of the WHO Grade IV glioma. Postoperatively, she did not wake up. An electroencephalogram demonstrated triphasic waves suggestive of encephalopathy. The probable diagnosis of ceftriaxone-induced encephalopathy was made after ruling out other causes of delayed awakening after surgery. Ceftriaxone was discontinued and the patient improved within 2 days of withdrawal of ceftriaxone. Conclusion: Drug-induced encephalopathy should be considered in the differential diagnosis of patients with delayed awakening after surgery. Discontinuation of the drug leads to the recovery of these patients.

The role of endoscopic third ventriculostomy in the treatment of hydrocephalus.

OBJECT: Hydrocephalus remains a major public health problem. Conventional treatment has relied on extracranial shunting of CSF to another systemic site, but this approach is associated with a high rate of complications. Endoscopic third ventriculostomy (ETV) is a novel treatment for select forms of hydrocephalus that can eliminate the need for implantation of a lifelong ventricular shunt system. However, the indications for ETV are contested and its long-term effectiveness is not well established. METHODS: The authors selected 100 consecutive patients who underwent ETV for hydrocephalus beginning in 1994. Patients were enrolled and treated at a single institution by a single surgeon. The primary outcome was success of ETV, with success defined as no need for subsequent surgery for hydrocephalus. RESULTS: Ninety-five patients satisfied the inclusion criteria. The mean follow-up period was 5.1 years (median 4.7 years) with follow-up data available for as long as 17 years. Patients commonly presented with headache (85%), ataxia (34%), emesis (29%), and changes in vision (27%). The success rate for ETV was 75%. Twenty-one patients (22%) in the series had malfunctioning shunts preoperatively and 13 (62%) were successfully treated with ETV. Preoperative inferior bowing of the third ventricle floor on MRI was significantly associated with ETV success (p < 0.05). CONCLUSIONS: Endoscopic third ventriculostomy is an effective and durable treatment for select patients with hydrocephalus. When successful, the procedure eliminates the lifelong complications associated with implanted ventricular shunts.

Anatomic hemispherectomy: historical perspective.

The history of surgical treatment for hemispheric epilepsy is rich with colorful twists and turns. The authors trace the evolution of the surgical treatment of hemispheric epilepsy from radical anatomic resections to current less invasive disconnection procedures. Anatomic hemispherectomy (AH) was first described by Dandy in 1928 as a treatment for gliomas. The first report of this technique to control seizures was by McKenzie in 1938. AH gained wide popularity but began to fall out of favor after the description of superficial cerebral hemosiderosis in 1966. To reduce the morbidity and mortality associated with AH, Rasmussen introduced functional hemispherectomy in 1974. The technique of hemispherotomy was introduced in the 1990 s to minimize the extent of brain removal while maximizing the white matter disconnections. Thus, surgery for hemispheric epilepsy has undergone dramatic transformation since the technique was first introduced. Less invasive techniques have been developed to reduce surgical morbidity. Although optimal seizure control is best achieved with radical AH, the newer less invasive disconnection techniques appear to achieve near-comparable postoperative seizure control with a significantly lower rate of complications.

Endoscopic transventricular selective amygdalohippocampectomy: cadaveric demonstration of a new operative approach.

OBJECTIVE: The microsurgical anatomy of the temporal region has been well described. However, there is a paucity of information about the transventricular endoscopic anatomy of the mesial temporal lobe, and little is known about endoscopic approaches to this region. In this report, we describe the technique of endoscopic amygdalohippocampectomy (AH). The endoscopic anatomy of the mesial temporal region both before and after AH is shown. METHODS: We used 4 silicon-injected cadaver heads for the study in our minimally invasive neurosurgery laboratory. The lateral ventricle was accessed through an occipital burr hole. RESULTS: Predissection transventricular endoscopic anatomy of this region showed the choroid plexus, hippocampus, amygdala, choroid fissure, and collateral eminence. The hippocampus, parahippocampal gyrus, and amygdala were removed endoscopically, keeping the pia on the inferior surface of the mesial temporal region intact. Postdissection anatomy of the mesial temporal region showed a clear view of the brainstem, posterior cerebral vessels, choroidal vessels, and tentorium. CONCLUSIONS: We studied the transventricular endoscopic anatomy of the mesial temporal region and described a technique for safe endoscopic AH. The advantages and potential risks of endoscopic AH are discussed, along with suggestions for minimizing complications. We believe that knowledge of the endoscopic anatomy of the mesial temporal lobe will be useful for endoscopic AH and the removal of other lesions in this region.

Utility of diffusion tensor imaging tractography in decision making for extratemporal resective epilepsy surgery.

PURPOSE: To assess the utility of diffusion tensor imaging tractography (DTIT) in decision making in patients considered for extratemporal resective epilepsy surgery. METHODS: We subjected 49 patients with drug-resistant focal seizures due to lesions located in frontal, parietal and occipital lobes to DTIT to map the white matter fiber anatomy in relation to the planned resection zone, in addition to routine presurgical evaluation. We stratified our patients preoperatively into different grades of risk for anticipated neurological deficits as judged by the distance of the white matter tracts from the resection zones and functional cortical areas. RESULTS: Thirty-seven patients underwent surgery; surgery was abandoned in 12 (24.5%) patients because of the high risk of postoperative neurological deficit. DTIT helped us to modify the surgical procedures in one-fourth of occipital, one-third of frontal, and two-thirds of parietal and multilobar resections. Overall, DTIT assisted us in surgical decision making in two-thirds of our patients. CONCLUSIONS: DTIT is a noninvasive imaging strategy that can be used effectively in planning resection of epileptogenic lesions at or close to eloquent cortical areas. DTIT helps in predicting postoperative neurological outcome and thereby assists in surgical decision making and in preoperative counseling of patients with extratemporal focal epilepsies.

Endoscopic total corpus callosotomy: cadaveric demonstration of a new approach.

BACKGROUND: Callosotomy is a surgical option for treatment of a small number of patients with intractable seizures who are not candidates for surgical resection. The procedure is done conventionally with the aid of a microscope. In this article, we describe a new technique of endoscopic callosotomy through a parasagittal burr hole in a cadaveric model. METHODS: We utilized this technique with a single frontal burr hole. Callosotomies were performed on 4 silicon-injected cadaver heads in our minimally invasive neurosurgical laboratory. RESULTS: We were able to successfully perform total callosotomies in all cadaveric specimens without injury to the adjacent neurovascular structures. The advantages of our technique over microsurgery are the minimally invasive nature of the exposure and the improved visualization of the vascular structures near the rostrum and genu of the corpus callosum. A potential disadvantage we anticipate is the difficulty controlling bleeding in the event of vascular injury. CONCLUSION: We believe that this minimally invasive approach could have potential clinical applications.

Minimally invasive endoscopic transventricular hemispherotomy for medically intractable epilepsy: a new approach and cadaveric demonstration.

OBJECT: Surgery for medically intractable epilepsy secondary to unihemispheric pathology has evolved from more aggressive hemispherectomy to less aggressive variations of hemispherotomy. The authors propose a novel minimally invasive endoscopic hemispherotomy that should give results comparable to conventional open craniotomy and microsurgery. METHODS: Endoscopic transventricular hemispherotomy was performed in 5 silicon-injected cadaveric heads in the authors' minimally invasive neurosurgery laboratory. The lateral ventricle was accessed endoscopically through a frontal and occipital bur hole. White matter disconnections were performed to unroof the temporal horn and to disconnect the frontobasal region, corpus callosum, and fornix. RESULTS: Using an endoscopic transventricular approach, all white matter disconnections were successfully performed in all 5 cadavers. CONCLUSIONS: The authors have demonstrated the feasibility of endoscopic transventricular hemispherotomy in a cadaveric model. The technique is simple and could be useful in a subgroup of patients with parenchymal volume loss and ventriculomegaly.

Role of three-dimensional fluid-attenuated inversion recovery (3D FLAIR) and proton density magnetic resonance imaging for the detection and evaluation of lesion extent of focal cortical dysplasia in patients with refractory epilepsy.

BACKGROUND: Focal cortical dysplasia (FCD) is often associated with epilepsy. Identification of FCD can be difficult due to subtle magnetic resonance imaging (MRI) changes. Though fluid-attenuated inversion recovery (FLAIR) sequence detects the majority of these lesions, smaller lesions may go unnoticed while larger lesions may be poorly delineated. PURPOSE: To determine the ability of a specialized epilepsy protocol in visualizing and delineating the extent of FCD. MATERIAL AND METHODS: We compared the imaging findings in nine patients with cortical malformation who underwent routine epilepsy MR imaging as well as a specialized epilepsy protocol. All imaging was done on a 1.5T MR unit. The specialized epilepsy protocol included 3D FLAIR in the sagittal plane as well as proton density (PD) and high-resolution T2-weighted (T2W) images in the transverse plane. RESULTS: In all nine patients, the specialized protocol identified lesion anatomy better. In three patients in whom routine MRI was normal, the specialized epilepsy protocol including 3D FLAIR helped in identifying the lesions. One of these patients underwent surgery, and histo-pathology revealed a cortical dysplasia. In one patient, lesion characterization was improved, while in the remaining patients the extent of the FCD was more clearly demonstrated in the 3D FLAIR and PD images. Statistical analysis of images for cortical thickness, cortical signal intensity, adjacent white matter abnormalities, and gray-white matter junction showed significant statistical difference in the ability of 3D FLAIR to assess these aspects over conventional images. PD images were also found superior to the routine epilepsy protocol in assessment of cortical signal, adjacent white matter, and gray-white matter junction. CONCLUSION: Specialized MRI sequences and techniques should be performed whenever there is a high suspicion of cortical dysplasia, especially when they remain occult on conventional MR protocols. These techniques can also be used to define lesion extent more precisely.

Non-surgical management of cystic prolactinomas.

Cystic prolactinomas are considered not amenable to dopamine agonist therapy. We present the results of dopamine agonist therapy in six patients with cystic prolactinomas. The inclusion criteria of patients were: (i) cystic macroadenomas with the cyst occupying more than 50% of the tumour volume; (ii) a serum prolactin value more than 150 ng/mL. All patients were males with a mean age of 35 years. The clinical presentations were erectile dysfunction in 66.6%, visual deficits in 50% and headache in 50% of patients. All patients were treated with bromocriptine only except one who was treated with both bromocriptine and cabergoline. The mean duration of follow up was 57.1 months. At the final follow-up 50% of patients had hormonal cure, 50% had radiological cure and 50% had reduction in the size of the tumour. Hence, it is appropriate to consider dopamine agonist therapy in patients with cystic prolactinomas before considering surgery.

Immediate postoperative death due to hypothalamic injury following surgery for craniopharyngioma.

Autonomic disturbances due to hypothalamic injury that result in postoperative death are rare complications following surgery for craniopharyngioma. We discuss the case of a child who died due to hypothalamic injury following radical excision of a multi-compartmental craniopharyngioma. Mechanisms and clinical manifestations of hypothalamic injury and ways to avoid this fatal complication are discussed.

Acute subdural hematoma after transsphenoidal surgery.

We report the case of a 48-year-old male who developed an acute subdural hematoma after transsphenoidal decompression of a pituitary adenoma followed by a lumbar drain to conservatively manage postoperative cerebrospinal fluid rhinorrhoea. An attempt is made to discuss the risk factors. The need for constant monitoring, early imaging and prompt treatment is stressed.

Epidermoid cysts of the velum interpositum.

The cistern of the velum interpositum is a space located between the corpus callosum dorsally and the roof of the third ventricle ventrally. Lesions located within the velum interpositum are rare and include meningiomas, pilocytic astrocytomas, atypical teratoid/rhabdoid tumors and arachnoid cysts. Epidermoid cysts in this location have not been reported previously. We report the clinical and radiological features of two patients with epidermoid cysts located in the velum interpositum. The patients presented with gait difficulty and features of raised intracranial pressure and magnetic resonance imaging demonstrated large tumors in the velum interpositum with intensities suggestive of epidermoid cysts. There was ventral displacement of the internal cerebral veins and dorsal displacement of the corpus callosum in keeping with a mass in the velum interpositum. Tumors of the third ventricle displace the internal cerebral veins dorsally. A transcallosal approach was used in both patients to effectively excise the tumors.

Supracerebellar arachnoid cyst - A rare cause of acquired Chiari I malformation.

Chiari I malformation (CM) associated with a cervico-thoracic syrinx due to supracerebellar arachnoid cyst has not been reported in the literature. We report such a case, managed by fenestration of the arachnoid cyst and foramen magnum decompression (FMD), aiming to reduce the inferiorly directed pressure on the cerebellum and eliminate the craniospinal pressure dissociation respectively. Imaging done post-operatively showed upward displacement of the cerebellar tonsils with a decompressed craniovertebral junction and disappearance of the syrinx.