1/44. Managing a dropped nucleus during the phacoemulsification learning curve.Three patients had a pars plana vitrectomy to remove retained nuclei within 72 hours after phacoemulsification performed by a surgeon making the transition from extra-capsular cataract extraction to phacoemulsification. After vitrectomy, the nuclei were brought to the midvitreous cavity from the retinal surface with a posterior segment phacofragmenter, emulsified, and completely removed. Then, a posterior chamber intraocular lens was implanted in the sulcus through the previous cataract surgery incision and remained well centered postoperatively. postoperative complications included cystoid macular edema in 1 patient and choroidal detachment in another. No other complications were detected. Final visual acuity ranged from 20/60 to 20/30.- - - - - - - - - - ranking = 1keywords = nucleus (Clic here for more details about this article) |
2/44. Hypertrophic olivary degeneration following surgical excision of brainstem cavernous hemangioma: a case report.Hypertrophic olivary degeneration (HOD) is a rare type of neuronal degeneration involving the dento-rubo-olivary pathway. It is distinguished from other types of neuronal degeneration in that hypertrophy, rather than atrophy, takes place in the neurons in the inferior olivary nucleus. Prior to the invention of magnetic resonance imaging (MRI), HOD was difficult to be detected, and a firm diagnosis could only be made at autopsy. We present a case of bilateral HOD following surgical excision of a cavernous hemangioma in the brainstem. The literature and imaging findings of this uncommon condition are reviewed.- - - - - - - - - - ranking = 0.25keywords = nucleus (Clic here for more details about this article) |
3/44. intention myoclonus of multiple sclerosis, its patho-anatomical basis and its stereotactic relief.The typical multiple sclerosis case considered here is especially informative from both the standpoint of its clinical course and on the basis of the autopsy findings. The foci responsible for the severe bilateral intention myoclonus of the trunk and limbs are the nerve cell losses in both red nuclei due to extensive and almost complete demyelination. Thereby the triangle of Mollaret between the red nucleus, inferior olives and dentate nucleus is involved as the patho-physiological circuit responsible for myoclonus. Stereotactic coagulation of dentato-thalamic fibres resulted in complete relief of intention myoclonus. With regard to the triggering of fresh demyelinating foci by stereotactic interventions, our point of view is as follows: Although a stereotactic operation introduces the possibility of triggering new demyelinating foci in less than 10% of the cases, such a possibility does not represent an absolute contra-indication to the stereotactic treatment of action myoclonus in multiple sclerosis, if the patient is informed accordingly.- - - - - - - - - - ranking = 0.5keywords = nucleus (Clic here for more details about this article) |
4/44. Transganglionic gracile response following limb amputation in man.Gracile neuroaxonal dystrophy (nad) is an distinctive morphological alteration of central projecting axon terminals of dorsal root ganglion neurons. Experimentally, lower limb amputation has been shown to accelerate the formation of gracile nad, suggesting that the transganglionic response to peripheral axotomy may play a role in its development. To determine if a similar response occurs in the human sensory nervous system following peripheral nerve injury, we have performed postmortem histopathological examinations of the dorsal column nuclei of three patients (aged 15, 55, and 77 years old); all of whom had undergone accidental or therapeutic unilateral limb amputation (1 year, 38 years, and 1 year 8 months prior to death, respectively). In a 15-year-old man who underwent therapeutic leg amputation, the gracile nuclei on the transected side revealed reactive gliosis and many small axonal spheroids. The spheroids and fine neurites were immunolabelled with antibodies for growth-associated protein-43, ubiquitin and neuropeptide y (NPY). Neither routine histological nor immunohistochemical methods demonstrated comparable changes in the contralateral gracile nucleus. In a 77-year-old man who underwent leg amputation, the gracile nucleus on the amputated side was gliotic and showed several NPY and ubiquitin-immunoreactive spheroids, which were not seen in the contralateral non-transected side. A 55-year-old man with a history of accidental arm amputation showed well-developed nad in the cuneate nucleus only on the transected side. This study clearly demonstrates the occurrence of transganglionic response to limb amputation in human dorsal column nuclei. The extent of the regenerative and/or degenerative responses may vary depending on the age of the patient and the time interval following the peripheral axotomy.- - - - - - - - - - ranking = 0.75keywords = nucleus (Clic here for more details about this article) |
5/44. Opacification of piggyback IOLs associated with an amorphous material attached to interlenticular surfaces.PURPOSE: To report the pathological and ultrastructural features and interval surgical management of an atypical case of opacification between piggyback intraocular lenses (IOLs). SETTING: Center for research on Ocular therapeutics and Biodevices, Storm eye Institute, Medical University of south carolina, Charleston, south carolina, and nature Coast EyeCare Institute and Surgery Center, Perry, florida, USA. methods: Opacification between 2 acrylic piggyback lenses was observed 16 months after implantation, with decreased best corrected visual acuity and a hyperopic shift. Elschnig pearls were observed in the peripheral interface between the lenses, and the central interface was occupied by an amorphous material. The pearls were surgically aspirated, but attempts to remove the central material were unsuccessful. The lenses were explanted and sent to the laboratory. Staining with hematoxylin and eosin (H&E), examination under a light microscope, and scanning electron microscopic analysis were performed. RESULTS: The surfaces of the anterior IOL were relatively clear. The amorphous material, mostly attached to the center of the anterior surface of the posterior IOL, was homogeneously stained with H&E. No cell nucleus was observed in this region. Scanning electron microscopy showed that the IOL edge presented a smooth, regular surface relatively free of deposits. The most central region was covered by an irregular layer of an amorphous compact material with some cracks, fissures, or both on its surface. CONCLUSIONS: Although the exact composition of the material between the lenses could not be established, hypotheses were advanced to understand the pathological mechanism associated with this condition. This case is different from those in previous reports of opacification composed of cortex and cells between piggyback IOLs.- - - - - - - - - - ranking = 0.25keywords = nucleus (Clic here for more details about this article) |
6/44. Transdural cauda equina incarceration after microsurgical lumbar discectomy: case report.OBJECTIVE AND IMPORTANCE: Complications usually occur when they are least expected. We present an unusual case of nerve entrapment after microsurgical discectomy. CLINICAL PRESENTATION: A patient undergoing uneventful first lumbar microsurgical discectomy developed severe back and leg pain and a progressive neurological deficit during the first postoperative night. Herniation of cauda equina nerve roots had occurred through an unnoticed minimal defect in the dura, which had not caused cerebrospinal fluid leakage. The roots were incarcerated and swollen, and they filled the space of the resected nucleus pulposus. It was presumed that elevation of intra-abdominal pressure and consequent increased intraspinal pressure during extubation led to the herniation of arachnoid and cauda equina roots. The nerve roots were then trapped and incarcerated in the manner of bowel loops in an abdominal wall hernia. INTERVENTION: During reoperation, the nerve roots were repositioned into the dural sac. The patient recovered without further complications and without long-term sequelae. CONCLUSION: All dural tears that occur during intraspinal surgery, even if they are small and the arachnoid is intact, should be closed with stitches or at a minimum with a patch of muscle or gelatin sponge with fibrin glue. Care should be taken to avoid increased intra-abdominal pressure during extubation. Excessive pain and progressive neurological dysfunction occurring shortly after microsurgical lumbar discectomy or any intraspinal procedure is indicative of possible hemorrhage with subsequent compression of nerve roots. The case reported here provides anecdotal evidence that this situation can also be caused by a herniation of cauda equina nerve roots through a small dural defect that was not evident during the initial operation.- - - - - - - - - - ranking = 0.25keywords = nucleus (Clic here for more details about this article) |
7/44. Bilateral crossed cerebello-cerebral diaschisis and mutism after surgery for cerebellar medulloblastoma.A 7-year-old boy developed mutism after surgery for cerebellar medulloblastoma. Postoperative magnetic resonance imaging (MRI) showed atrophy of the cerebellar vermis and both cerebellar hemispheres, predominantly on the right side. Single photon emission computed tomography (SPECT) with technetium-99m-ethyl cysteinate dimer (Tc-99m ECD) revealed decreased cerebral blood flow (CBF) in the bilateral thalami, bilateral medial frontal lobes, and left temporal lobe in addition to the cerebellar vermis and both cerebellar hemispheres when mutism was manifest, indicating the existence of bilateral crossed cerebello-cerebral diaschisis (BCCCD). Circulatory disturbance in both cerebellar hemispheres secondary to tumor resection probably caused BCCCD in both cerebral hemispheres, predominantly in the left, via the dentatothalamocortical pathway (DTCP). With recovery of his mutism, CBF increased in the right thalamus, bilateral medial frontal lobes and left temporal lobe. Thus BCCCD was improved, with only a slight decrease in CBF still persisting in the left thalamus. The mechanism of mutism may have involved damage to the cerebellar vermis (the site of incision at operation), the left dentate nucleus (heavily infiltrated by the tumor) and the right dentate nucleus of the cerebellum (affected by circulatory disturbance secondary to acute postoperative edema). The SPECT findings suggested that mutism was associated with BCCCD-induced cerebral circulatory and metabolic hypofunction in the supplementary motor area mediated via the DTCP.- - - - - - - - - - ranking = 0.5keywords = nucleus (Clic here for more details about this article) |
8/44. Metastatic brainstem tumor manifesting as hearing disturbance--case report.A 53-year-old male, who had undergone a left upper lung lobectomy for cancer 2 years previously, presented with metastatic brainstem tumor manifesting as hearing disturbance. At first an otorhinolaryngologist treated him for senile sensorineural hearing disturbance. However, he suffered gait ataxia and was referred to our department. On admission, neurological examination found mild cerebellar ataxia on the left and gait unsteadiness. Neurootological analysis revealed central-type sensorineural hearing disturbance on the left both in the pure tone audiogram and speech discrimination test. neuroimaging studies revealed a ring-like enhanced mass centered in the ventral left middle cerebellar peduncle, partly extending to the inferior cerebellar peduncle. Peritumoral edema extending to the ipsilateral cochlear nucleus was recognized. He underwent surgery via a left lateral suboccipital transcondylar approach. The histological diagnosis was adenocarcinoma identical with the primary lung cancer. Intra-axial brainstem metastatic lesion can be a cause of hearing disturbance, so should be included in the differential diagnosis for a patient complaining of hearing disturbance, especially with a past history of cancer.- - - - - - - - - - ranking = 0.25keywords = nucleus (Clic here for more details about this article) |
9/44. serratia spondylodiscitis after elective lumbar spine surgery: a report of two cases.STUDY DESIGN: This report describes two cases of acute spondylodiscitis, caused by, complicating two different conditions: microdiscectomy for herniated nucleus pulposus and decompressing laminotomy for spinal stenosis. OBJECTIVE: To describe a rare and life-threatening spinal infection and discuss its successful management. SUMMARY OF BACKGROUND DATA: To our knowledge, no published reports in the English language have described this potentially devastating infection as a complication of elective noninstrumented discectomy or decompressive laminotomy. methods: Two cases of a very early onset of acute spondylodiscitis, caused by, after minimally invasive lumbar spine surgeries are presented. The elapsed time between these two complications was 1 week. The clinical presentation was characteristically stormy in both cases. On postoperative day 2, the patients developed high fever with intense chills and concomitant acute low back pain rapidly increasing in severity. The overall clinical appearance was alarming. The patients were carefully investigated immediately and scrutinized for possible origin of the infection. Treatment consisted of prompt intravenous antibiotics and surgical debridement. RESULTS: The history and clinical manifestations of postoperative spondylodiscitis were corroborated with magnetic resonance imaging findings and bacteriologic and hematologic laboratory examination. blood cultures revealed as the responsible pathogenic microorganism. The source of the pathogens was contaminated normal saline used for surgical lavage. Both patients were able to completely resume their previous occupations after aggressive surgical debridement/irrigation and 3 months of antibiotic treatment. CONCLUSIONS: may become a potential pathogen, causing severe spinal infection after elective surgery. For prompt diagnosis and effective treatment of this life-threatening infection, one should maintain high index of suspicion and should not procrastinate in initiating treatment, which should consist of appropriate intravenous antibiotics and surgical debridement.- - - - - - - - - - ranking = 0.25keywords = nucleus (Clic here for more details about this article) |
10/44. Hemiballism after subthalamotomy in patients with Parkinson's disease: report of 2 cases.The occurrence of persistent hemiballism after subthalamotomy for Parkinson's disease (PD) has not been described as frequently as mild or transient dyskinesia. We report on 2 patients with advanced PD who developed hemiballism and/or dyskinesia after subthalamotomy. One patient with a small lesion confined to the subthalamic nucleus (STN) developed persistent hemiballism; the other with a larger lesion involving the STN and also the zona incerta presented with a transient dyskinesia in a single limb. We conclude that a precise STN lesion might bear a potential risk of persistent hemiballism.- - - - - - - - - - ranking = 0.25keywords = nucleus (Clic here for more details about this article) |
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