Pedro Santos Silva

Learning curve and complications of minimally invasive transforaminal lumbar interbody fusion

OBJECT Minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) has the potential advantage of minimizing soft-tissue damage and reducing recovery time compared to open procedures. A steep learning curve has been described for the technique. The aim of the present study was to define the learning curve that describes the progress of a single surgeon performing the MI-TLIF. METHODS One hundred fifty consecutive patients with degenerative lumbar disease who underwent 1- or 2-level MI-TLIF were included in the study. Operative time, corrected operative time per level, and complications were analyzed. The learning curve was assessed using a negative exponential curve-fit regression analysis. RESULTS One hundred ten patients underwent 1-level and 18 patients underwent 2-level MI-TLIF; the remaining 22 underwent a single-level procedure plus an ancillary procedure (decompression at adjacent level, vertebral augmentation through fenestrated pedicle screws, interspinous device at adjacent level). Negative exponential curves appropriately described the relationship between operative time and experience for 1-level surgery and after correction of operative time per level (R(2) = 0.65 and 0.57). The median operative time was 140 minutes (interquartile range 120-173 minutes), and a 50% learning milestone was achieved at Case 12; a 90% learning milestone was achieved at Case 39. No patient required transfusion in the perioperative period. The overall complication rate was 12.67% and the most frequent complication was a dural tear (5.32%). Before the 50% and 90% learning milestones, the complication rates were 33% and 20.51%, respectively. CONCLUSIONS The MI-TLIF is a reliable and effective option for lumbar arthrodesis. According to the present study, 90% of the learning curve can be achieved at around the 40th case.

The infratentorial supracerebellar approach in surgery of lesions of the pineal region

Background: Surgery of pineal region lesions is considered a challenging task, due to the particular relationship of lesions in this location with neural and vascular structures. Few series with a significant experience of dealing with these patients have been reported. Methods: We review our experience using infratentorial supracerebellar approach in the surgery of pineal region, regarding the extension of the removal, postoperative morbidity, and discussing details of the surgical technique. In all cases, a supracerebellar infratentorial approach was used in the semi sitting position. Results: A total of 32 patients were operated in the past 20 years (3 germinomas, 3 teratoma, 3 pineocitoma, 2 pineal tumor of intermediate differentiation, 6 pineoblastomas, 6 low grade astrocytoma, 2 glioblastoma, 2 metastasis, 1 ependymoma, 1 epidermoid tumor, 1 cavernoma, and 2 arachnoid cyst). Total removal was achieved in 15 cases and subtotal extensive removal in 7 patients. In the remaining cases, only partial removal was possible, due to the involved pathological types. There was no surgical mortality and no cases of cerebellar venous infarction. Morbidity consisted of transient ocular movement disturbance in 14 patients, transient ataxia in 3 patients, and 1 case of local cerebrospinal fluid (CSF) fistula with meningitis that required surgical treatment. Conclusion: Supracerebellar infratentorial is a safe approach to lesions in the pineal region, and total or extensive subtotal removal is possible in most cases, with acceptable morbidity.

Trans-lamina terminalis approach for third ventricle and suprasellar tumours

BACKGROUND The trans-lamina terminalis (TLT) approach to the suprasellar region and third ventricle is complex, with risks of visual and hormonal deficits. However, the postoperative deficits might not be directly related to opening of the lamina terminalis but to the close relationship of tumours with vital neural and vascular structures. The analysis of results using this approach was the objective of this study. MATERIAL AND METHODS The TLT approach was used in 29 patients (18 craniopharyngiomas, 5 astrocytomas, 5 germinomas and 1 ganglioglioma). The extent of tumour removal, mortality and morbidity (especially visual or hormonal deficits) were studied. RESULTS Complete tumour removal was achieved in 15 patients, subtotal extensive removal (more than 90%) in 9 cases and partial removal in 5 cases. Panhypopituitarism developed in 22 patients. Total tumour removal was associated with the development of endocrinological disturbances. There was worsening or the onset of new visual field defects in 4 cases. Postoperative endocrine and visual deficits were in the range generally described regarding surgery for tumours in this region. CONCLUSION The TLT approach allows for extensive removal of third ventricle and suprasellar tumours, without increased risks of visual and hormonal deficits, compared to those described regarding surgery for lesions in this region.

Epithelioid sarcoma of the spine: Case report and literature review

Epithelioid sarcomas are rare mesenchymal neoplasms mainly arising in the limbs of young adults. We report the case of a 24-year-old male presenting low back pain radiating to both lower limbs, constipation and urinary retention. The MRI scan showed an intraspinal lesion extending from L4 to S2. Surgery resulted in gross total removal of the extradural lesion and partial removal of the intradural component. The immunohistological study of the lesion was consistent with an epithelioid sarcoma. The patient was submitted to radiotherapy and chemotherapy, but a local recurrence of the lesion and dissemination along the neuraxis were observed 3 months after surgery. Despite treatment, the patient died 4 months after the surgical procedure due to multiorgan failure. Despite there being isolated reports of epithelioid sarcomas appearing in the spine, this is, to our knowledge, the first case with intradural extension.

Osteomyelitis of the Atlantooccipital Joint in an Intravenous Drug User: A Case Report and Review of the Literature

Vertebral osteomyelitis accounts for approximately 1% to 7% of all bone infections. Pyogenic osteomyelitis of the cervical spine is rare, representing 5.9% of spinal cases; 35% of these cases occur in the thoracic spine, and 57% occur in the lumbar spine. The occurrence in the upper cervical spine is even more rare, accounting for only 0.7% of cases1-3. In patients with a history of intravenous drug use, the involvement of the cervical spine is more frequent and may be as high as 27%4. Cervical osteomyelitis is more common in men than in women and most often occurs between the fifth and seventh decades; the most frequent pathogen is Staphylococcus aureus (25% to 64% of cases). However, Pseudomonas aeruginosa is also commonly found in intravenous drug users1,4,5. Patients with diabetes, chronic immunosuppression, a history of intravenous drug use, or infection with human immunodeficiency virus are particularly susceptible to vertebral osteomyelitis1. Pyogenic osteomyelitis of the atlantooccipital junction is extremely rare. In the literature, most of the cases concerning osteomyelitis in the upper cervical spine occur in the atlas, axis, or both1,6,7. To our knowledge, no cases of pyogenic osteomyelitis of the atlantooccipital joint in intravenous drug users have previously been reported in the literature. The patient was informed that data concerning the case would be submitted for publication, and he provided consent. A forty-two-year-old man with a history of smoking, intravenous drug use (heroin), and hepatitis C presented to the emergency department with nuchal pain, which became worse with cervical motion and radiated to the right side of the head. The symptoms had progressively worsened in the past two weeks after a low-energy fall (2 m high) without direct trauma to the …

Paraparesis as the Presenting Form of a Lumbar Hemorrhagic Synovial Cyst

Intraspinal synovial or ganglion cysts are uncommon lesions associated with degenerative lumbosacral spine disease. They have been reported with increasing frequency in part because of the availability of increasingly sensitive imaging studies1. These juxtafacet cysts are usually located in the lumbar spine and mostly present with back pain associated with progressive radiculopathy, or less often with spinal cord compression syndrome2-5. Hemorrhage into these cysts is uncommon but explains acute symptomatology caused by nerve root compression6. To our knowledge, there have been only sixteen cases of hemorrhagic juxtafacet cysts associated with motor deficit reported in the English-language literature2-5,7-17. We report a case in which hemorrhage into an L4-L5 juxtafacet cyst presented as paraparesis; we also describe its successful treatment and review the literature. The patient was informed that data concerning the case would be submitted for publication, and he provided consent. An eighty-year-old man presented with a history of chronic intermittent bilateral lumbar pain. Five days before admission while exerting minor physical effort, he experienced a sudden exacerbation of lumbar pain radiating to both legs; he also noticed weakness and impaired sensation in both lower limbs that made it difficult to walk without help. He had no incontinence or bowel/bladder dysfunction. There had been no previous traumatic event, and he did not use anticoagulant medication. Findings at clinical examination revealed asymmetrical hyporeflexic paraparesis. The motor deficit was more pronounced in flexion and dorsiflexion of the ankle, was grade 3/5 in the left lower limb and grade 4/5 in the right, and there was hypesthesia in the left L4 and bilateral L5 and S1 territories. The straight leg-raising test was positive bilaterally. Computed tomography (CT) revealed an isodense left intracanalar extramedullary cystic mass adjacent to the …

Correcção de escoliose lombar degenerativa por técnica minimamente invasiva

El tratamiento quirurgico de la escoliosis degenerativa consiste habitualmente en instrumentaciones y fusiones mas o menos extensas, asociadas a morbilidad significativa. La evolucion tecnologica ha abierto el camino para tecnicas menos invasivas que permiten obtener resultados comparables a los de las tecnicas tradicionales, minimizando el trauma de la cirugia. Presentamos el caso de paciente de sexo femenino, de 63 anos de edad, sometida a descompresion lumbar posterior en enero de 2009, debido a marcadas alteraciones degenerativas. Pocos meses despues del procedimiento, la paciente refirio agravamiento de la lumbalgia y ciatica derecha. El estudio de imagenes mostro empeoramiento de la escoliosis degenerativa L2-L5 asociada a extrusion discal L2-L3 derecha calcificada, fractura bilateral de los pediculos de L3 y espondilolistesis degenerativa grado I L5-S1. Fue sometida a la reintervencion quirurgica utilizando una tecnica minimamente invasiva que consistio en TLIF L2-L3, L3-L4, L4-L5 y L5-S1 y fijacion transpedicular L2-S1 bilateral, con correccion de la deformidad en los planos sagital y coronal. El caso clinico que presentamos ilustra el potencial de los enfoques minimamente invasivos en el tratamiento quirurgico de las escoliosis degenerativas, debiendo ser una opcion siempre presente cuando se consideran los beneficios para el paciente.