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Jonathan A Friedman

Publications and source records attributed to Jonathan A Friedman.

34 records · Page 2Linked to original sources
PubMed2002

Cerebellar hemorrhage after spinal surgery: report of two cases and literature review.

OBJECTIVE AND IMPORTANCE: Cerebellar hemorrhage remote from the site of surgery may complicate neurosurgical procedures. We describe our experience with two cases of cerebellar hemorrhage after spinal surgery and review the three cases previously reported in the literature to determine whether these cases provide insight regarding the pathogenesis of remote cerebellar hemorrhage. CLINICAL PRESENTATION: One of our patients developed cerebellar hemorrhage in the vermis and right hemisphere after transpedicular removal of a partially intradural T9-T10 herniated disc with the patient in the prone position. The other patient developed cerebellar hemorrhage in the vermis and bilateral hemispheres after L3-S1 decompression and instrumentation with the patient in the prone position, during which the dura was inadvertently opened. INTERVENTION: The first patient was treated conservatively and had mild residual dysarthria and gait ataxia 2 months after surgery. The second patient underwent exploration and revision of the lumbar wound with primary dural repair. The cerebellar hemorrhage was treated conservatively, and the patient had mild dysarthria and ataxia 1 month after surgery. CONCLUSION: Cerebellar hemorrhage must be considered in patients with unexplained neurological deterioration after spinal surgery. Dural opening with loss of cerebrospinal fluid has occurred in every reported case of cerebellar hemorrhage complicating a spinal procedure, supporting the hypothesis that loss of cerebrospinal fluid is central to the pathogenesis of this condition. Because remote cerebellar hemorrhage can occur after procedures with the patient in the supine, sitting, and prone positions, patient positioning seems unlikely to play a causative role in its occurrence.

Adult↗
PubMed2002

Surgical treatment of fibrous dysplasia of the skull in children.

INTRODUCTION: We evaluate the role of surgery in the treatment of fibrous dysplasia of the skull in children. METHODS: We identified 48 consecutive cases of fibrous dysplasia of the skull that were surgically treated at a single institution over a 23-year interval. The 28 patients that initially presented during the first two decades of life were selected for further analysis. Presenting symptoms, signs, surgical treatment, surgical outcome and the state of the disease at the extended follow-up interval were recorded. RESULTS: Fibrous dysplasia of the skull in children most often involved the frontal, sphenoid and ethmoid bones. Most patients presented with facial asymmetry or proptosis. A gross total resection was achieved in 7 patients, subtotal resection in 17 patients, and 4 patients underwent biopsy alone. Over the follow-up interval, 7 patients had symptomatic progression of subtotally resected fibrous dysplasia and 3 patients had asymptomatic progression. The extent of resection was correlated with recurrence risk. CONCLUSIONS: In order to prevent progression of disease, an attempt at gross total resection is indicated in cases of fibrous dysplasia of the skull in childhood where the risk of neurologic morbidity is low and cosmetic results will be acceptable.

Child↗
PubMed2002

Endovascular treatment of an internal carotid artery pseudoaneurysm following transsphenoidal surgery. Case report.

Internal carotid artery (ICA) pseudoaneurysm formation following transsphenoidal surgery is a rare but potentially lethal complication. Direct surgical repair with preservation of the ICA may be difficult. The feasibility of endovascular coil embolization with parent artery preservation for an iatrogenic ICA pseudoaneurysm is undefined. A 40-year-old man was referred to the authors' institution after identification of a pseudoaneurysm of the left ICA following transsphenoidal resection of a pituitary macroadenoma. The pseudoaneurysm was treated via an endovascular approach that included stent-assisted coil embolization of the lesion. Follow-up angiographic studies obtained 1 year later demonstrated complete occlusion of the aneurysm, and the patient remains asymptomatic. Stent-assisted coil embolization of this iatrogenic pseudoaneurysm was successful in achieving complete, angiographically confirmed aneurysm obliteration, with preservation of the ICA and short-term prevention of hemorrhage or carotidcavernous fistula. The endovascular method provided an effective, relatively low-risk treatment for this difficult lesion, and was an excellent alternative to direct surgical repair. Nonetheless, long-term follow-up review is required before definitive treatment recommendations can be made.

Adenoma↗
PubMed2002

Intraoperative lidocaine injection into the carotid sinus during endarterectomy.

OBJECT: Many surgeons inject a local anesthetic agent into the carotid sinus before carotid endarterectomy in an attempt to ameliorate perioperative hemodynamic instability. The purpose of this study is to analyze the effect of carotid sinus injection with lidocaine on perioperative hemodynamics and complications. METHODS: The authors prospectively studied 92 patients in whom 100 consecutive carotid endarterectomies were performed by a single surgeon (eight procedures were bilateral). Patients were randomly assigned to one of two groups, in which either 0.5 ml of 1% lidocaine was injected into the carotid sinus nerve or no injection of lidocaine was administered before the arteriotomy. All patients were treated postoperatively according to a standard endarterectomy protocol. There were no significant differences between the two groups in the incidence of hypertension, hypotension, or the use of vasoactive medications in the operating room following restoration of carotid artery (CA) blood flow, in the recovery room, or in the intensive care unit. CONCLUSIONS: Injection of lidocaine into the carotid sinus at the time of endarterectomy is not associated with a significant improvement in any hemodynamic factor, from the time of restoration of CA blood flow to postoperative Day 1.

Aged↗
PubMed2002

Volumetric quantification of Fisher Grade 3 aneurysmal subarachnoid hemorrhage: a novel method to predict symptomatic vasospasm on admission computerized tomography scans.

OBJECT: Predicting which patients with aneurysmal subarachnoid hemorrhage (SAH) will develop delayed ischemic neurological deficit (DIND) due to vasospasm remains subjective and unreliable. The authors analyzed the utility of a novel software-based technique to quantify hemorrhage volume in patients with Fisher Grade 3 aneurysmal SAH. METHODS: Patients with aneurysmal SAH in whom a computerized tomography (CT) scan was performed within 72 hours of ictus and demonstrated Fisher Grade 3 SAH were analyzed. Severe DIND was defined as new onset complete focal deficit or coma. Moderate DIND was defined as new onset partial focal deficit or impaired consciousness without coma. Fifteen consecutive patients with severe DIND, 13 consecutive patients with moderate DIND, and 12 consecutive patients without DIND were analyzed. Software-based volumetric quantification was performed on digitized admission CT scans by a single examiner blinded to clinical information. There was no significant difference in age, sex, admission Hunt and Hess grade, or time to admission CT scan among the three groups (none, moderate, or severe DIND). Patients with severe DIND had a significantly higher cisternal volume of hemorrhage (median 30.5 cm3) than patients with moderate DIND (median 12.4 cm3) and patients without DIND (median 10.3 cm3; p < 0.001). Intraparenchymal hemorrhage and intraventricular hemorrhage were not associated with DIND. All 13 patients with cisternal volumes greater than 20 cm3 developed DIND, compared with 15 of 27 patients with volumes less than 20 cm3 (p = 0.004). CONCLUSIONS: The authors developed a simple and potentially widely applicable method to quantify SAH on CT scans. A greater volume of cisternal hemorrhage on an admission CT scan in patients with Fisher Grade 3 aneurysmal SAH is highly associated with DIND. A threshold of cisternal hemorrhage volume (> 20 cm3) may exist above which patients are very likely to develop DIND. Prospective application of software-based volumetric quantification of cisternal SAH may predict which patients will develop DIND.

Adult↗
PubMed2002

Transient postictal magnetic resonance imaging abnormality of the corpus callosum in a patient with epilepsy. Case report and review of the literature.

Transient neuroimaging abnormalities associated with seizure activity have received little attention in the literature. The authors report a focal magnetic resonance (MR) imaging abnormality of the corpus callosum in a patient following a secondary generalized seizure. A 27-year-old right-handed man presented with a history of medically refractory partial seizures since the age of 1 year. The results of an MR imaging study obtained 4 months prior to the patient undergoing video-electroencephalography monitoring were unremarkable. After the patient discontinued all antiepileptic medications, a secondary generalized seizure of right temporal origin was recorded. Five days later, repeated MR imaging revealed a nonenhancing 14 x 11-mm ovoid hyperintense lesion in the splenium of corpus callosum. The patient was asymptomatic, and his neurological and neurocognitive examinations remained unremarkable. Follow-up MR imaging 5 weeks and 1 year later demonstrated near-complete resolution of the lesion. Benign and transient abnormalities in the splenium can occur as a periictal phenomenon. A high index of suspicion and follow-up imaging may prevent further unwarranted intervention.

Adult↗
PubMed2002

Preoperative ventriculostomy and rebleeding after aneurysmal subarachnoid hemorrhage.

OBJECT: Despite the widespread use of ventriculostomy in the treatment of acute hydrocephalus after aneurysmal subarachnoid hemorrhage (SAH), there is no consensus regarding the risk of rebleeding associated with ventriculostomy before aneurysm repair. This present study was conducted to assess the risk of rebleeding after preoperative ventriculostomy in patients with aneurysmal SAH. METHODS: The authors reviewed the records of all patients with acute SAH who were treated at a single institution between 1990 and 1997. Thus, the records of 304 consecutive patients in whom an aneurysmal SAH source was documented on angiographic studies and who had presented to the authors' institution within 7 days of ictus were analyzed. Re-bleeding was confirmed by evidence of recurrent hemorrhage on computerized tomography scans in all cases. Forty-five patients underwent ventriculostomy for acute hydrocephalus after aneurysmal SAH at least 24 hours before aneurysm repair. Ventriculostomy was performed within 24 hours of SAH in 38 patients, within 24 to 48 hours in three patients, and more than 48 hours after SAH in four patients. The mean time interval between SAH and surgery in patients who did not undergo ventriculostomy was no different from the mean interval between ventriculostomy and surgery in patients who underwent preoperative ventriculostomy (3.6 compared with 3.8 days, p = 0.81). Fourteen (5.4%) of the 259 patients who did not undergo ventriculostomy suffered preoperative aneurysm rebleeding, whereas two (4.4%) of the 45 patients who underwent preoperative ventriculostomy had aneurysm rebleeding. CONCLUSIONS: No evidence was found that preoperative ventriculostomy performed after aneurysmal SAH is associated with an increased risk of aneurysm rebleeding when early aneurysm surgery is performed.

Acute Disease↗
PubMed2002

Use of cerebrospinal fluid flow rates measured by phase-contrast MR to predict outcome of ventriculoperitoneal shunting for idiopathic normal-pressure hydrocephalus.

OBJECTIVE: To determine whether favorable clinical response and magnitude of improvement are associated with increased aqueductal cerebrospinal fluid (CSF) flow rates in patients who undergo ventriculoperitoneal shunting (VPS) for idiopathic normal-pressure hydrocephalus (NPH). PATIENTS AND METHODS: Between January 1995 and June 2000, 49 patients (14 men and 35 women; mean age, 72.9 years; range, 54-88 years) underwent magnetic resonance quantification of aqueductal CSF flow followed by VPS for presumed idiopathic NPH at the Mayo Clinic, Rochester, Minn. Logistic regression models for the odds of any improvement in score as a function of aqueductal CSF flow and separate models for any improvement in gait, incontinence, cognition, and total score were constructed. RESULTS: Forty-two patients (86%) had improvement in gait at postoperative follow-up (mean, 10 months). Of the 32 patients with incontinence, 27 (69%) improved. Of the 36 patients with cognitive impairment, 16 (44%) improved. In univariate and fully adjusted models, increased CSF flow through the aqueduct was not significantly associated with improvement or the magnitude of improvement in gait, cognition, or incontinence. Thirty-six patients underwent high-volume lumbar puncture preoperatively, of whom 5 (14%) had no response. The aqueductal CSF flow rates of these 5 patients were significantly higher than those of the patients who improved after lumbar puncture. Postoperative complications occurred in 15 patients. The aqueductal CSF flow rates in these 15 patients were not significantly different from those of patients who experienced no complications. CONCLUSION: Among patients who underwent VPS for the treatment of NPH, measurement of CSF flow through the cerebral aqueduct did not reliably predict which patients would improve after shunting or the magnitude of improvement.

Aged↗
PubMed2002

Propofol.

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Adult↗
PubMed2002

Biodegradable polymer grafts for surgical repair of the injured spinal cord.

PURPOSE: Biodegradable polymers have been used in the surgical repair of peripheral nerves, but their potential for use in the central nervous system has not been exploited adequately. This article discusses concepts related to the engineering of a biodegradable polymer graft for surgical repair of the injured spinal cord and explores the potential means by which such a device might promote axon regeneration and functional recovery after spinal cord injury. CONCEPT: A biodegradable polymer implant with controlled microarchitecture can be engineered, and its composition can be optimized for implantation in the spinal cord. RATIONALE: The use of a biodegradable polymer implant has the dual advantages of providing a structural scaffold for axon growth and a conduit for sustained-release delivery of therapeutic agents. As a scaffold, the microarchitecture of the implant can be engineered for optimal axon growth and transplantation of permissive cell types. As a conduit for the delivery of therapeutic agents that may promote axon regeneration, the biodegradable polymer offers an elegant solution to the problems of local delivery and controlled release over time. Thus, a biodegradable polymer graft would theoretically provide an optimal structural, cellular, and molecular framework for the regrowth of axons across a spinal cord lesion and, ultimately, neurological recovery. CONCLUSION: Biodegradable polymer grafts may have significant therapeutic potential in the surgical repair of the injured spinal cord. Further research should be focused on the bioengineering, characterization, and experimental application of these devices.

Absorbable Implants↗
PubMedDate not supplied

Predictors of outcome after endovascular treatment of cerebral vasospasm.

BACKGROUND AND PURPOSE: Angioplasty and intra-arterial papaverine are promising treatments for severe symptomatic vasospasm after subarachnoid hemorrhage (SAH), but there is little information on the clinical factors that predict treatment outcome. We sought to determine variables for predicting functional outcome in this setting. METHODS: We reviewed 81 consecutive patients with symptomatic cerebral vasospasm from aneurysmal SAH treated with percutaneous balloon angioplasty or selective intra-arterial papaverine infusion between 1990 and 2000 (105 procedures). Logistic regression analysis was used to assess the effect of various clinical and angiographic factors on outcome. RESULTS: Mean patient age was 54 years (range, 29-88 years). Twenty-nine patients (36%) presented with poor-grade (World Federation of Neurologic Surgeons [WFNS] grade IV or V) SAH. Clinical deficits were global in 55 patients (70%), and angiographic vasospasm was diffuse in 53 (65%). Endovascular treatment consisted of transluminal angioplasty alone (18 procedures, 17%), intra-arterial papaverine infusion (65 procedures, 62%), or both (22 procedures, 21%). Unequivocal arterial dilatation was achieved in all but two patients, and major complications occurred in 2% of the procedures. Ten patients (12%) died in the hospital, and 36 (44%) recovered poorly. Permanent deficits attributable to cerebral vasospasm were present in 37 patients (52% of survivors). On multivariate logistic regression analysis, advanced age and poor WFNS grade at presentation were predictive of poor clinical outcome. CONCLUSION: Advanced age and poor clinical status at the time of SAH onset are predictive of poor clinical outcome despite endovascular treatment with angioplasty or intra-arterial papaverine in patients with symptomatic vasospasm.

Adult↗