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Biomedical subjects

W T Couldwell

Publications and source records attributed to W T Couldwell.

At least 19 recordsLinked to original sources
PubMed2006

Spontaneous regression of a cystic cavum septum pellucidum.

A persistent cavum septum pellucidum (CSP) is present in approximately 0.73% of adults, although its incidence ranges from 0.14 to 18.9% depending on the detection method. Cystic CSP is even rarer. A cyst causing mass within the CSP can obstruct the intraventricular foramen, leading to blockage of CSF flow and possible hydrocephalus, often justifying surgical intervention. We describe spontaneous decompression of a cystic CSP in a 36-year-old man. Initial MRI showed a cystic CSP with lateral bowing of the septal walls to 1.9 cm. Follow-up MRI 15 months later demonstrated no lateral bowing, and the septal wall width was 1.0 cm. This spontaneous decompression was not explained by the one previously described case report of cystic CSP regression.

Adult↗
PubMed2006

Remote cerebellar hemorrhage.

Remote cerebellar hemorrhage (RCH) is a rare but benign, self-limited complication of supratentorial craniotomies that, to the best of our knowledge, has not been described in the imaging literature. RCH can be an unexpected finding on routine postoperative imaging studies and should not be mistaken for more ominous causes of bleeding such as coagulopathy, hemorrhagic infarction, or cortical vein occlusion. Cerebellar hemorrhage in the typical setting can be identified as RCH and does not require more extensive or invasive evaluation.

Aged↗
PubMed2006

Incidental giant arachnoid granulation.

Arachnoid granulations may expand the dural sinuses or inner table of the skull. Although usually incidental, giant arachnoid granulations that are of sufficient size to fill the lumen of a dural sinus and cause local dilation or filling defects can rarely cause symptoms due to sinus obstruction leading to venous hypertension. This 31-year-old man presented with a 3-month history of progressive bifrontal headaches and a giant arachnoid granulation at the posterior superior sagittal sinus. Intrasinus pressure measurements showed no significant pressure difference across the lesion to explain the headaches, which were then treated medically. Dural sinus pressure measurement, in certain cases of giant arachnoid granulations, can be used to exclude the lesion as the cause of the patient's symptoms.

Adult↗
PubMed2005

Distal ventriculoperitoneal shunt failure secondary to Clostridium difficile colitis.

Distal ventriculoperitoneal shunt obstruction is typically associated with cerebrospinal fluid (CSF) infection, fluid pseudocysts, bowel obstruction, bowel perforation, or improper shunt placement in the abdomen. We describe a unique etiology for distal shunt obstruction secondary to Clostridium difficile pancolitis that occurred because of inflammation and ascites, which led to incomplete drainage and absorption of CSF. This case illustrates the importance of considering distal shunt obstruction in a patient with signs of abdominal pathology in the setting of mental status changes, and the effective treatment of this patient initially with distal catheter externalization followed by internalization of a new distal catheter after resolution of the pancolitis.

Ascites↗
PubMed2005

Thrombosed basilar apex aneurysm presenting as a third ventricular mass and hydrocephalus.

Aneurysms presenting as third ventricular masses are uncommon; most are giant aneurysms arising from the basilar apex. We present a case of a thrombosed basilar apex aneurysm presenting as a third ventricular mass and hydrocephalus in a 55-year-old man. The case is unique in the literature as the aneurysm was completely thrombosed and angiographically occult. The lesion was explored to verify the diagnosis and a third ventriculostomy resolved the patient's symptoms. Completely thrombosed aneurysms should be considered in the differential diagnosis of symptomatic third ventricular masses, even when angiographic studies are negative. The literature on aneurysms presenting as third ventricular masses is reviewed.

Humans↗
PubMed2004

Revision of vagal nerve stimulator electrodes: technical approach.

BACKGROUND: As the number of implanted vagal nerve stimulators grows, the need for removal or revision of the devices will become more frequent. Our purpose was to demonstrate the feasibility of complete removal of the vagal nerve stimulator electrode using microsurgical technique. METHODS: . Operative databases at the University of Utah (1995 through 2002), Westchester Medical Center (1995 through 2001), and University of Arizona Health Sciences Center (1995 through 1999) were retrospectively reviewed. Patients who had undergone removal or revision of a previously placed vagal nerve stimulator electrode were identified. Patients who had a vagal nerve stimulator device removed but had the lead trimmed and incompletely removed were excluded. FINDINGS: Seven patients underwent complete removal of the lead. Microsurgical dissection allowed removal of the helical electrode from the vagus nerve without apparent physiological consequences. Four patients had a new electrode placed just proximal to the original lead site. The operative procedure required an additional 30 minutes to complete compared with initial device placement. The four patients who underwent replacement of the electrode demonstrated normal device function and lead resistance at the time of postoperative follow-up. Each experienced a return to prior stimulation response and seizure control. CONCLUSIONS: This series suggests that the electrode can be removed from the vagus nerve and repositioned without significant consequence in most cases.

Adult↗
PubMed2004

Bilateral testicular enlargement and seminoma in a patient with acromegaly.

Growth hormone (GH) excess has been associated with soft tissue changes and an increase in the incidence of colonic polyps and gastrointestinal cancer. We describe a patient with endogenous GH excess caused by a pituitary tumour, resulting in acromegaly. The patient had bilateral testicular enlargement, with tumour of the right testicle. Pituitary MRI revealed a macroadenoma. After resection of the pituitary tumour, GH levels fell below 0.5 ng/ml, with acromegaly resolution. Testicular resection revealed seminoma. Following acromegaly resolution, the enlarged remaining testicle decreased in size. The implications of the testicular enlargement and seminoma in the presence of a GH-secreting tumour are discussed.

Acromegaly↗
PubMed2003

Endoscopic-assisted craniofacial resection of esthesioneuroblastoma: minimizing facial incisions--technical note and report of 3 cases.

The surgical management of esthesioneuroblastoma with anterior skull base involvement has traditionally been craniofacial resection, which combines a bifrontal craniotomy with a transfacial approach. The latter usually involves a disfiguring facial incision, mid-facial degloving, lateral rhinotomy, and/or extensive facial osteotomies, which may be cosmetically displeasing to the patient. The advent of angled endoscopes has provided excellent magnification and illumination for surgeons to remove tumors using minimally invasive techniques. The authors describe their experience with three cases of esthesioneuroblastoma, which were surgically removed using a transnasal endoscopic approach, avoiding transfacial incisions. Preoperative radiographs were reviewed and tumors were staged according to the Kadish staging system. One patient had a recurrent esthesioneuroblastoma (Kadish stage B), which was removed entirely through a transnasal endoscopic approach. Two patients had intracranial extension (Kadish stage C), which were resected with a combined approach, endoscopically from below and a bifrontal craniotomy from above, to remove intracranial disease. All patients underwent reconstruction of the anterior skull base. Esthesioneuroblastomas confined to the nasal and paranasal cavities (Kadish stage A and B) were readily accessible through the transnasal endoscopic approach. If there was significant intracranial disease (Kadish stage C), adding a bifrontal craniotomy provided excellent exposure for complete resection of involved tumor. All patients underwent complete tumor resection with negative margins. None developed a cerebrospinal fluid (CSF) leak. The endoscopic-assisted craniofacial approach for the surgical management of esthesioneuroblastomas provides excellent exposure, adequate visualization, and the cosmetic benefit of avoiding an external facial incision.

Adult↗
PubMed2002

Enlargement of a vestibular schwannoma after stereotactic radiotherapy.

BACKGROUND: Radiosurgery has been increasingly advocated as a primary treatment for vestibular schwannoma (VS), and recently fractionation of the dose has been proposed as a method to decrease the risk of radiation injury when treating larger tumors. METHOD: The authors describe a 48-year-old woman who presented with right-sided hearing loss and new-onset tinnitus, with a progressive decrease in facial sensation. The diagnosis of a large right cerebellopontine angle VS was made on magnetic resonance imaging (MRI). The patient was treated with a course of fractionated stereotactic radiotherapy (SRT) (5 treatments of 4 Gy to the 90% isodose line over a 3-week period). FINDINGS: Six months after the initiation of therapy, her symptoms increased, and a repeat MRI scan demonstrated that her tumor had increased in size, producing significant brainstem compression. She then underwent complete surgical resection of the tumor, with resolution of her symptoms. INTERPRETATION: Stereotactic radiosurgery has been effective in controlling small VSs with low complication rates. Larger tumors pose a risk for increasing in size and producing symptoms from mass effect with SRT. There are at present limited data demonstrating safety and efficacy of fractionated SRT for the treatment of larger tumors.

Dose Fractionation, Radiation↗
PubMed2001

Vertebral arterial dissection associated with Klippel-Feil syndrome in a child.

BACKGROUND: Vertebral artery dissection resulting in stroke is rare in children. We report here on a 7-year-old boy with Klippel-Feil abnormality, who presented with a pontine infarction after a supervised swimming session. METHODS: Evaluation after a second acute neurological event included a formal cerebral angiogram, which revealed a complete upper basilar artery occlusion and right vertebral arterial dissection. Cervical spine radiographs demonstrated an associated fusion of the C2 and C3 vertebrae. Anticoagulation therapy was initiated, and the neurological deficits associated with the pontine infarction resolved. Anticoagulation was discontinued after 6 months of therapy, with no recurrence of symptoms. CONCLUSION: Vertebral artery dissection may rarely be associated with Klippel-Feil abnormality in children.

Aortic Dissection↗
PubMed2001

Irving S. Cooper and the early surgical management of movement disorders. Video history.

Irving S. Cooper was a pioneer in the field of functional neurosurgery. During his very productive and controversial career, he proposed the surgical treatment of Parkinson disease (PD) by ligating the anterior choroidal artery to control tremor and rigidity. Subsequently, he developed seminal techniques for chemopallidectomy and cryothalamectomy for PD. He also attempted to use electrical stimulation of the cerebellum or the thalamus to treat spasticity. Cooper continued his work on brain stimulation until his death in 1985. He made video recordings of nearly all of his patients during his tenure (1977-1985) at New York Medical College. Cooper's clinical video recordings were reviewed, and selected footage was compiled into a video history of Cooper's surgical management of various movement disorders. Included are pre-, post-, and some intraoperative recordings that Cooper made to document his treatment of patients with PD, tremor, Wilson disease, cerebral palsy, chorea, dystonia musculorum deformans, and some rarer entities.

History, 20th Century↗
PubMed2001

X-irradiation of the contusion site improves locomotor and histological outcomes in spinal cord-injured rats.

We have determined whether X-irradiation of the injury site can oppose tissue loss and improve recovery of locomotor function following contusion injury of the spinal cord. Contusion injury was produced in rats at the level of T10 with a weight drop device. Localized X-irradiation (20 Gy) of the injury site was performed at 20 min and 1, 2, 4, 7, and 17 days postinjury. Locomotor recovery was then determined with the 21-point Basso, Beattie, and Bresnahan (BBB) scale. X-irradiation enhanced recovery of locomotor function during a subsequent 6-week observation period when administered 20 min and 1 or 2 days following contusion injury (final BBB score approximately 7-8). X-irradiation at 4-17 days postinjury did not significantly affect final locomotor scores compared with unirradiated rats (final BBB score approximately 2), in marked contrast to previous studies where X-irradiation applied only at 17-18 days benefitted transection injury. The extent of recovery was directly related to measurements of sparing of spinal cord tissue at the contusion center. Because the treatment time window occurred earlier in contusion than reported for transection injury, the results suggest that contusion injury rapidly initiates underlying radiation-sensitive processes that occur only following a delay of several weeks after transection injury. Further optimization of X-ray treatment may lead to a useful therapeutic modality for use in spinal cord contusion injury.

Animals↗
PubMed2001

Reversal of radiographically impending stroke with multiple intraarterial papaverine infusions in severe diffuse cerebral vasospasm induced by subarachnoid hemorrhage.

BACKGROUND: Selective intraarterial infusion of papaverine is used in the treatment of symptomatic cerebral vasospasm induced by aneurysmal subarachnoid hemorrhage (SAH). Delays in instituting therapy for vasospasm can lead to irreversible cerebral infarction and a devastating outcome. Endovascular papaverine treatment of vasospasm in the presence of low-attenuation lesions on computed tomography (CT) is controversial, because of the fear of reperfusion hemorrhage in completed infarcts. METHOD: Two patients with aneurysmal SAH who subsequently developed severe diffuse vasospasm were identified. In both patients, large areas of low-attenuation change suggesting impending cerebral infarction were seen on CT scans. The patients received multiple infusions of intraarterial papaverine in an effort to treat vasospasm refractory to medical management. FINDINGS: After multiple intermittent administrations of papaverine, which initially appeared to increase the low-attenuation changes, there was dramatic reversal of the radiographic findings. There was also improvement in circulation time, transcranial Doppler velocities, and clinical outcome. INTERPRETATION: These findings suggest that in some patients, intraarterial infusions of papaverine initiated in the earliest stages of ischemia may exacerbate the radiographic appearance of low-attenuation changes, but may ultimately reverse the evolution of cerebral infarction.

Adult↗
PubMed2001

Laparoscopic anterior lumbar interbody fusion precipitating pituitary apoplexy.

OBJECTIVE: Pituitary apoplexy may be the first presentation of a previously undiagnosed pituitary adenoma. Although many mechanisms of pituitary apoplexy have been proposed in the literature, the exact pathogenesis remains unclear. Many predisposing events have been implicated in the pathogenesis, however, the role of laparoscopy precipitating pituitary apoplexy has not been previously described. The authors present a case of pituitary apoplexy in a previously undiagnosed pituitary adenoma, which presented in the immediate post-operative period after a laparoscopic anterior lumbar interbody fusion. CLINICAL PRESENTATION: A 45-year-old man presented with a sudden onset of headache, photophobia, diplopia, visual field deficits, and decreased visual acuity in the immediate post-operative period after an uneventful laparoscopic anterior lumbar interbody fusion. Results of computed tomography of the brain revealed a hyperdense suprasellar mass without any signs of subarachnoid blood. The patient underwent magnetic resonance imaging, which revealed a hemorrhagic pituitary tumor with lateral and suprasellar extension, with compression of the cavernous sinus and optic chiasm, respectively. An urgent transsphenoidal decompression of the hemorrhagic pituitary adenoma was performed. Post-operatively, the patient demonstrated marked neurological improvement with recovery of visual acuity and extraocular movements. CONCLUSION: To the authors' knowledge, this is the first case reported in the literature of a laparoscopic procedure precipitating pituitary apoplexy. Recognition of this rare complication of laparoscopic surgery, and the importance of rapid diagnosis and urgent surgical treatment are emphasized.

Adenoma↗
PubMed2001

Symptomatic subdural hygroma and temporal lobe edema after translabyrinthine removal of acoustic neuroma.

The translabyrinthine approach is familiar to most neurosurgeons and neuro-otologists and is frequently used to remove acoustic neuromas. Some of the complications associated with this surgery include cerebrospinal fluid (CSF) leaks, meningitis, and rarely fat graft prolapse. The authors report a 60-year-old woman who underwent a translabyrinthine approach and microsurgical resection of a right-sided 1-cm acoustic neuroma. Initially, she was discharged home after an uneventful postoperative course. Four days later, she sought treatment in the emergency room complaining of headaches, dizziness, and lethargy. A computed tomographic (CT) scan showed a large right-sided subdural hygroma and right temporal lobe edema. The patient underwent burr hole evacuation of the collection and placement of a subdural drain, after which the edema in the temporal lobe and hygroma resolved. We speculate that the underlying mechanism was the result of inadvertant damage to the venous drainage and an arachnoid tear that was not appreciated during surgery. Neurosurgeons and neuro-otogists should be aware of this unusual complication of translabyrinthine surgery and its possible underlying mechanisms.

Case Reports↗
PubMed2001

Approaches to the sellar and parasellar region: anatomic comparison of endonasal-transsphenoidal, sublabial-transsphenoidal, and transethmoidal approaches.

Various surgical approaches have been described for treating lesions which arise in the sellar region. The popular transnasal-transsphenoidal and transethmoidal-transsphenoidal approaches avoid the morbidity associated with transcranial operations while allowing enough exposure to successfully remove most lesions that arise in and around the sella. The goal of the present study was to accurately quantify the amount of exposure to the sellar and suprasellar region that the transethmoidal-transsphenoidal, endonasal-transphenoidal, and sublabial-transsphenoidal approaches provide. Each of the three approaches was performed on 14 formalin fixed heads with the aid of the operative microscope. The distances of relevant surgical landmarks, and the amount of exposure superior and anterior to the dorsum sella as well as the lateral exposure obtained through each of these approaches was carefully recorded. The mean distances were then used to calculate the volume of exposure offered by each approach. It was found that the sublabial-transsphenoidal approach afforded the greatest volume of exposure superior and anterior to the dorsum sella. The endonasal-transsphenoidal and the transethmoidal approaches were both found to offer less suprasellar volume exposure, with the transethmoidal approach offering the least. The authors believe the information obtained through this study illustrates some important anatomical relationships which can be used to advantage by the surgeon to tailor the most appropriate approach, depending upon the precise location of the lesion either within the sella or suprasellar region.

Brain Neoplasms↗
PubMed2001

Giant petrous carotid aneurysm treated by submandibular carotid-saphenous vein bypass. Case report.

Petrous and cavernous sinus carotid artery (CA) aneurysms that are not amenable to clip ligation or endovascular therapy may be successfully treated by a saphenous vein bypass, thereby preserving the patency of the CA. The authors report the unique case of a 47-year-old man with a giant fusiform aneurysm of the petrous CA, who presented with a rapid onset of a lateral rectus palsy and diplopia. The lesion was treated by trapping the aneurysm and performing a saphenous vein bypass from the cervical to the intracranial CA. The saphenous vein graft was routed beneath the condyle of the mandible to reduce the overall length of the graft, thereby increasing the likelihood of long-term patency and offering protection to the graft by the mandible, temporal muscle zygomatic process, and masseter and temporal muscles. The presentation and technical aspects of the bypass graft in this unique case are discussed.

Anastomosis, Surgical↗