(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient is a 48 year old Caucasian male with a past medical history of hypertension, gastroesophageal reflux disease, irritable bowel syndrome, chronic headaches, anxiety, depression, chronic low back pain secondary to spinal stenosis status post L3 through L5 laminectomies in 2009, and end-stage osteoarthritis in bilateral hips status post total left hip (March) and total right hip (September) arthroplasties with metal-on-metal prostheses in 2008. The patient worked in the construction industry for many years and performed daily tasks that resulted in his chronic hip disease, including heavy lifting and prolonged kneeling. Following the left hip replacement, his pain was vastly improved and he did well with no complications. However, following the right hip replacement, he noted increased bilateral hip pain, right more than left. In April 2012, he presented to an outpatient clinic with these complaints, in addition to complaints of increasing confusion, headaches, blurry vision for about two weeks, and short-term memory loss. Radiologic imaging was performed at that time, but failed to reveal signs of joint failure. Interestingly, a blood cobalt level was drawn and returned 11.4 µg/L (reference range: <1.8 µg/L). He subsequently underwent a revision of the right hip in October 2012, replacing the metal-on-metal joint with a non-metal surface prosthesis. A repeat blood cobalt level was drawn after the surgery and returned 5 µg/L. He remained clinically stable following the right hip revision, but in February 2013 he presented to an outside hospital after he sustained a traumatic fall in his basement. He attributed the fall to symptoms of progressive cognitive decline, including confusion, lethargy, short-term memory loss, and depression, which he noted had worsened since his hip procedures in 2008. Computed tomography (CT) and magnetic resonance imaging (MRI) scans of the head did not reveal significant acute pathology, an electroencephalogram (EEG) was also negative for seizure-like activity or any other pathologic activity in the brain, and all other work-ups were essentially negative. On admission to the hospital, he stated that he had a history of elevated blood cobalt levels, but the patient's previous laboratory studies were not available for review by his clinicians. A repeat blood cobalt level was drawn during his hospitalization and returned 3.1 µg/L. The patient was eventually discharged from the hospital with follow-up at an outpatient toxicology clinic for further evaluation.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

This 48 year old male presented in October 2000 with sudden (<12 hours) right sided weakness. His admission blood pressure was 178/107. Nervous system examination found reduced visual acuity but no double vision or visual field defects. Right sided power was reduced to 0/5 (right arm) and 3/5 (right leg), with normal tone, reduced bulk and increased reflexes. Plantars were bilaterally up-going with ankle clonus. Admission CT scan showed a 3cm (transverse) x 2cm (sagittal) deep left intracerebral hematoma with surrounding edema. The occipital horns of the lateral ventricles were compressed by bilateral hypointense white matter lesions (figure 1). The patient became unresponsive the day after admission, with bilateral fixed pupils and a repeat CT showed hematoma expansion with new onset left uncal herniation. The bilateral white matter hypointensities were unchanged. Despite further treatment, on this day, with family consent, the patient was extubated and expired. Consent was given to perform a complete autopsy.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 48- year- old female presented with right sided moderate to severe headache for 2 years. She also had difficulty in right lateral vision for 4-5 months. For the last 2 months she developed difficulty in swallowing liquids and solids. The patient was unable to walk properly and had a tendency to fall on her right side for last 15 days. Her past history was significant for hypertension for which she was taking antihypertensives. On neurological examination, the patient was conscious and oriented. There was right sided cranial nerve palsy which includes III, IV, V, IX, X and XI nerves. The cerebellar signs were positive on right side. The MRI showed a mass lesion probably in relation to trigeminal nerve on right side showing extension anteriorly to Meckels cave and posteriorly to the cerebellopontine angle. The lesion was hyperintense on T2 and hypointense on T1 weighted images. After the administration of intravenous contrast gadolinium DTPA, the lesion showed moderate to intense homogenous enhancement. The lesion extended into the cavernous sinus and petrous bone on the right side. It measured 5.7x3.1x5.5 cm. The lesion was causing marked indentation of the pons and pontocerebellar junction on the right side. The rest of the brain parenchyma revealed no abnormal signal intensity. These findings were suggestive of a right trigeminal nerve schwannoma showing extension and mass effect or a petrous meningioma. Patient underwent suboccipital retrosigmoid craniotomy with excision of the mass lesion.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient was a 48-year-old woman with a one-year history of back pain, who recently developed right upper quadrant pain that radiated to her side and back. The past medical history included cervical cancer in 1983, bipolar disorder, fibromyalgia, and Hashimoto's thyroiditis. Medications at presentation listed Synthroid, lithium, and Aviane (ethinyl estradiol and levonorgestrel). She had been on birth control pills for the past 20 years.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 48-year-old right handed female presented with a 6 month history of progressive decrease of sensation in right upper and lower extremities following a fall after returning from a golf course. She attributed that fall to the loss of sensation, which improved spontaneously over 10 minutes with some residual numbness in the right leg. Her symptoms progressed and she developed difficulty in walking and lifting her right leg. She also complained of neck discomfort and chronic headaches. Neurological examination revealed mild patchy loss of pinprick and light touch sensation in the right upper and lower extremity and trunk with no consistent dermatomal distribution. There was diminished vibration sensation in the right knee. Deep tendon reflex was absent in the right ankle. Plantar reflexes were downgoing. Her gait was stiff with mild circumduction of the right leg. Rest of the motor and cranial nerve examinations were grossly normal.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 49-year old female with no significant past medical history except for psoriasis presented to our department complaining of increasing neck pain over 4 weeks accompanied by hoarseness and dysphagia. In addition, she reported general fatigue as well as problems with fine motor skills of her right arm and right leg. On MRI we found a left anterolateral extra-axial space-occupying lesion (45 x 32 x 32 mm) of the foramen magnum that shifted the brain stem to the right, another small para-torcular (8mm) extra-axial lesion over the left cerebellar convexity and an extra-axial mass over the right sylvian fissure (shown in Figs. 1a and 1b). Considering the clinical symptoms of the patients, we opted for surgery of the foramen magnum tumor and the small peritorcular lesion of the left cerebellar convexity due to its proximity. After angioembolization of the supratentorial tumor and foramen magnum mass, a far lateral suboccipital craniotomy was performed on the left side in park bench position. Surgery was complicated by the difficult anatomy with the lower cranial nerves and brain stem perforators of the vertebral artery running on the surface of the tumor. Using a combination of intratumoral ultrasonic aspiration and peritumoral microdissection, the foramen magnum mass could be removed completely and the dural attachment was coagulated (corresponding to a Simpson grade II resection in meningioma surgery). The small para-torcular lesion had a clear arachnoidal plane and could be completely resected without complications. The patient had no new postoperative neurological deficits and the postoperative MRI showed a complete resection of both lesions ( Figs. 1a and 1b). At three months follow-up, the preoperative symptoms recovered completely. The foramen magnum mass was diagnosed as a WHO grad I meningothelial meningioma - the diagnosis of the smaller cerebellar para-torcular mass is discussed below in detail.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 48 years-old patient without significant medical history or without bleeding disorder is addressed to our institution for acute headache and bitemporal hemianopsia. No hormonal secretion was detected, and the patient had a pituitary insufficiency with loss of libido, diffuse hair loss, asthenia and slowing. An MRI showed a 47mm pituitary lesion occupying the sella turcica with central necrosis. This lesion was hypointense in T1 sequence, enhanced with gadolinium injection and hyperintense in T2 sequence (Fig.1). Then, a transsphenoidal excision surgery was decided. A first surgery was performed, but the resection of the tumor lead to an extensive bleeding and the tumor could not be resected entirely. Three days later, because of incomplete resection a second excision procedure was decided leading to an extensive bleeding and a subtotal surgical resection. The visual symptoms of the patient improved quickly after the surgery.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 49-year-old man presented with a two-month history of headache and recent twenty pound weight loss. He was diagnosed with cluster headaches at an outside hospital and treated with triptans. One week after the initial onset of headache, he developed right jaw and facial pain with facial weakness, accompanied by inability to fully close his right eye and mouth. He was given one dosage of steroids at an outside hospital for cluster headache with full resolution of his symptoms. However, a week later, his right facial weakness recurred and persisted. About four weeks later, he complained about similar jaw/facial pain and weakness of his left side, which appeared to be more severe than those of his right side. He also developed occasional diplopia on far gaze and left lateral gaze. He did not experience any changes in hearing or taste. Magnetic resonance imaging of brain revealed abnormal enhancement of the third, fifth, seventh and eighth cranial nerves with various degree of diffuse enlargement (arrows pointing to trigeminal nerves in Figure 1). Patchy enhancement of the nerve roots in the distal lumbar region was also noted. A gallium whole body scan did not reveal any significant abnormality. Repeated CSF studies showed low glucose levels, elevated protein levels and elevated cell counts. Extensive peripheral blood and CSF work-up for infectious disease, autoimmune, demyelinating disorders and neoplasia were negative except for a positive T-cell lymphotropic virus type 1 (HTLV-1) antibody. His HIV-1/2 ELISA was negative. Peripheral blood flow cytometry showed mature WBCs with slightly elevated CD4:CD8 ratio. CSF flow cytometry revealed large granular T-cell lymphocytosis consisting of CD3/CD56/CD57+ lymphocytes (>97% of gated lymphocytes), which was interpreted as due to a reactive process. A working diagnosis of neurosarcoidosis was made and the patient was treated with prednisone 60 mg daily for two weeks followed by dexamethasone 4 mg daily for another two weeks. However, the patient's symptoms worsened, leading to heightened suspicion of a malignant neoplasm. Dexamethasone was discontinued and he subsequently underwent biopsy of the enlarged left infraorbital nerve (Figure 2, arrows).

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 49-year-old female, who suffered trauma to the left fronto-parietal region from a gymnasium weight two years previously, presented with a 12-month history of an enlarging lump in the same area. There were no associated visual, sensory or neurological symptoms. On examination there was a large smooth, non-tender, bony hard mass measuring 8 x 6 centimetres at its base, with mild to moderate overlying alopecia. It was non-pulsatile with no bruits. The lesion was percussion dull and there was no regional lymphadenopathy.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 49 year old female presented to the hospital with nausea and vomiting. CT scan of the abdomen demonstrated gastric and duodenal masses and retroperitoneal lymphadenopathy. She underwent retroperitoneal lymph node, gastric body, gastric antrum and duodenal biopsies.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 49-year old man presented with chief complaints of stuffy nose, worsening headache for the past 3 weeks and binocular diplopia which developed over a period of 4 days. Significant past medical history included hypertension and a biopsy performed from a right chest wall mass, approximately 1 year ago. Pathology report was not available at the time of presentation. General physical examination was unremarkable and neurological examination revealed signs of bilateral sixth nerve palsy.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

Patient is a 49 year old male who does not have a significant past medical history until he developed tooth pain. He was found to have tooth abscesses which were treated with antibiotics. A month later, he had his wisdom teeth pulled and experienced delayed healing and persistent pain. He then began to feel fatigued, weak, and dyspnea on exertion, prompting a visit to his primary care doctor. Laboratory studies revealed pancytopenia resulting in a bone marrow biopsy.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 44-year-old man with a four-year history of progressive neuropsychiatric symptoms, including irritability, apathy and hyposexuality, was admitted to another hospital because of increasing impairment of executive functions, delusions, paranoid ideation and mild cognitive decline. Physical and laboratory examinations were normal. An EEG study showed focal theta activity over the right frontal areas, whereas a brain MRI revealed mild cortical atrophy of the right hemisphere.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 49-year-old man presented with fever and altered mental status. He had a complex prior medical history notable for type I diabetes mellitus with end-stage renal disease and peripheral vascular disease. Eight years prior to admission he underwent pancreatic and renal transplantation secondary to diabetes. The renal transplantation procedure was initially complicated by intra-operative myocardial infarction, and subsequently by acute and chronic allograft rejection. Consequently, the patient had been on long-term immunosuppressive therapy. He also suffered from chronic atrial fibrillation requiring warfarin and had undergone cardiac valve replacement one year earlier.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A family member had gone to pick up this 49 year old, white female, from her apartment for a family dinner and found her unresponsive in bed, wearing her blue pajamas. Scene investigation revealed multiple, randomly situated medication bottles around the apartment, some with the lids off. Some of the bottles were empty and others contained the following prescribed pills: Desipramine, Imipramine and Fluoxetine. The prescriptions had been filled two days prior and a significant number of pills were unaccounted for. There was no scene evidence of any struggle or any signs of violence. There was a strong family and personal history of long standing depression. She was under psychiatric treatment and attended several support groups for the depressed. She had mentioned an intention to commit suicide four years prior, but there was no recent mention or suggestion of suicide. She seemed stable and responded well to therapy. There was no history of any previous suicide attempt (para-suicide). No suicide note was found at the apartment.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 49 year old woman with a remote history of borderline serous tumor of the right ovary presented with a history of headache, nausea and vomiting. MRI imaging of the brain showed mixed solid and cystic pineal region mass causing obstruction at the level of the cerebral aqueduct associated with marked hydrocephalus (Fig. 1). The patient underwent a third ventriculostomy and pineal region tumor biopsy.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 4-year-old girl presented with right hemiparesis and ataxia. Her symptoms progressed rapidly and she could no longer ambulate without assistance. Her exam was remarkable for severe right-sided weakness of both upper and lower extremities. The MRI showed a left thalamic, hemorrhagic mass measuring up to 42 x 33 x 38 mm (Figs. 1a, 1b). Mass effect on the third ventricle was noted with resultant acute obstructive hydrocephalus. Interval placement of an EVD at the time of presentation helped mildly improve ventricle size. Gross total resection was performed by a parietal craniotomy and inner hemispheric, transcallosal approach.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient is a 5 month old male born to a G2P1 mother at 36 weeks gestation by Cesarean section. The infant was discharged home on day 4 of life.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient is a 4 week-old male infant born at 41 weeks gestation via Cesarean section to a 26 year-old mother who received good prenatal care. Prenatal ultrasounds performed at 20 weeks and 40 weeks gestational age were unremarkable. The delivery was uneventful. On physical exam in the newborn nursery the baby was noted to have right cryptorchidism and a palpable right-sided abdominal mass.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

Following an unremarkable prenatal course, a full-term male was floppy at birth and experienced respiratory difficulty. By one month of age, decreased proximal shoulder tone and head lag were apparent. Despite physical therapy, gross motor skills lagged. By 20 months of age, an EMG showed decreased activation of motor units. The patient walked with flat arches and an awkward gait and had bilateral ptosis. Reflexes were difficult to elicit. At the age of four, he developed dilated cardiomyopathy with an ejection fraction as low as 10%. Heart transplantation was performed.